summaryrefslogtreecommitdiffstats
path: root/docs/manual/mod/mod_ssl.html.en
blob: 1b63ab730f5855ae8410087232be1bdb1389a8b3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!--
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
              This file is generated from xml source: DO NOT EDIT
        XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
      -->
<title>mod_ssl - Apache HTTP Server</title>
<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" />
<link href="../images/favicon.ico" rel="shortcut icon" /></head>
<body>
<div id="page-header">
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
<p class="apache">Apache HTTP Server Version 2.5</p>
<img alt="" src="../images/feather.gif" /></div>
<div class="up"><a href="./"><img title="&lt;-" alt="&lt;-" src="../images/left.gif" /></a></div>
<div id="path">
<a href="http://www.apache.org/">Apache</a> &gt; <a href="http://httpd.apache.org/">HTTP Server</a> &gt; <a href="http://httpd.apache.org/docs/">Documentation</a> &gt; <a href="../">Version 2.5</a> &gt; <a href="./">Modules</a></div>
<div id="page-content">
<div id="preamble"><h1>Apache Module mod_ssl</h1>
<div class="toplang">
<p><span>Available Languages: </span><a href="../en/mod/mod_ssl.html" title="English">&nbsp;en&nbsp;</a></p>
</div>
<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Strong cryptography using the Secure Sockets
Layer (SSL) and Transport Layer Security (TLS) protocols</td></tr>
<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="module-dict.html#ModuleIdentifier">Module�Identifier:</a></th><td>ssl_module</td></tr>
<tr><th><a href="module-dict.html#SourceFile">Source�File:</a></th><td>mod_ssl.c</td></tr></table>
<h3>Summary</h3>

<p>This module provides SSL v2/v3 and TLS v1 support for the Apache
HTTP Server.  It was contributed by Ralf S. Engelschall based on his
mod_ssl project and originally derived from work by Ben Laurie.</p>

<p>This module relies on <a href="http://www.openssl.org/">OpenSSL</a>
to provide the cryptography engine.</p>

<p>Further details, discussion, and examples are provided in the
<a href="../ssl/">SSL documentation</a>.</p>
</div>
<div id="quickview"><h3 class="directives">Directives</h3>
<ul id="toc">
<li><img alt="" src="../images/down.gif" /> <a href="#sslcacertificatefile">SSLCACertificateFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcacertificatepath">SSLCACertificatePath</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcadnrequestfile">SSLCADNRequestFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcadnrequestpath">SSLCADNRequestPath</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcarevocationcheck">SSLCARevocationCheck</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcarevocationfile">SSLCARevocationFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcarevocationpath">SSLCARevocationPath</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcertificatechainfile">SSLCertificateChainFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcertificatefile">SSLCertificateFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcertificatekeyfile">SSLCertificateKeyFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslciphersuite">SSLCipherSuite</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslcryptodevice">SSLCryptoDevice</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslengine">SSLEngine</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslfips">SSLFIPS</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslhonorcipherorder">SSLHonorCipherOrder</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslinsecurerenegotiation">SSLInsecureRenegotiation</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslocspdefaultresponder">SSLOCSPDefaultResponder</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslocspenable">SSLOCSPEnable</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslocspoverrideresponder">SSLOCSPOverrideResponder</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslocsprespondertimeout">SSLOCSPResponderTimeout</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslocspresponsemaxage">SSLOCSPResponseMaxAge</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslocspresponsetimeskew">SSLOCSPResponseTimeSkew</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#ssloptions">SSLOptions</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslpassphrasedialog">SSLPassPhraseDialog</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslprotocol">SSLProtocol</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxycacertificatefile">SSLProxyCACertificateFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxycacertificatepath">SSLProxyCACertificatePath</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxycarevocationcheck">SSLProxyCARevocationCheck</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxycarevocationfile">SSLProxyCARevocationFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxycarevocationpath">SSLProxyCARevocationPath</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxycheckpeercn">SSLProxyCheckPeerCN</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxycheckpeerexpire">SSLProxyCheckPeerExpire</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxyciphersuite">SSLProxyCipherSuite</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxyengine">SSLProxyEngine</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxymachinecertificatechainfile">SSLProxyMachineCertificateChainFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxymachinecertificatefile">SSLProxyMachineCertificateFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxymachinecertificatepath">SSLProxyMachineCertificatePath</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxyprotocol">SSLProxyProtocol</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxyverify">SSLProxyVerify</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslproxyverifydepth">SSLProxyVerifyDepth</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslrandomseed">SSLRandomSeed</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslrenegbuffersize">SSLRenegBufferSize</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslrequire">SSLRequire</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslrequiressl">SSLRequireSSL</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslsessioncache">SSLSessionCache</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslsessioncachetimeout">SSLSessionCacheTimeout</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslsessionticketkeyfile">SSLSessionTicketKeyFile</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstaplingcache">SSLStaplingCache</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstaplingerrorcachetimeout">SSLStaplingErrorCacheTimeout</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstaplingfaketrylater">SSLStaplingFakeTryLater</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstaplingforceurl">SSLStaplingForceURL</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstaplingrespondertimeout">SSLStaplingResponderTimeout</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstaplingresponsemaxage">SSLStaplingResponseMaxAge</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstaplingresponsetimeskew">SSLStaplingResponseTimeSkew</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstaplingreturnrespondererrors">SSLStaplingReturnResponderErrors</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstaplingstandardcachetimeout">SSLStaplingStandardCacheTimeout</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslstrictsnivhostcheck">SSLStrictSNIVHostCheck</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslusername">SSLUserName</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslusestapling">SSLUseStapling</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslverifyclient">SSLVerifyClient</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#sslverifydepth">SSLVerifyDepth</a></li>
</ul>
<h3>Topics</h3>
<ul id="topics">
<li><img alt="" src="../images/down.gif" /> <a href="#envvars">Environment Variables</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#logformats">Custom Log Formats</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#notes">Request Notes</a></li>
<li><img alt="" src="../images/down.gif" /> <a href="#authzproviders">Authorization providers for use with Require</a></li>
</ul></div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="envvars" id="envvars">Environment Variables</a></h2>

<p>This module can be configured to provide several items of SSL information
as additional environment variables to the SSI and CGI namespace. This
information is not provided by default for performance reasons. (See
<code class="directive">SSLOptions</code> StdEnvVars, below.) The generated variables
are listed in the table below. For backward compatibility the information can
be made available under different names, too. Look in the <a href="../ssl/ssl_compat.html">Compatibility</a> chapter for details on the
compatibility variables.</p>

<table class="bordered">

<tr>
 <th><a name="table3">Variable Name:</a></th>
 <th>Value Type:</th>
 <th>Description:</th>
</tr>
<tr><td><code>HTTPS</code></td>                         <td>flag</td>      <td>HTTPS is being used.</td></tr>
<tr><td><code>SSL_PROTOCOL</code></td>                  <td>string</td>    <td>The SSL protocol version (SSLv3, TLSv1, TLSv1.1, TLSv1.2)</td></tr>
<tr><td><code>SSL_SESSION_ID</code></td>                <td>string</td>    <td>The hex-encoded SSL session id</td></tr>
<tr><td><code>SSL_SESSION_RESUMED</code></td>           <td>string</td>    <td>Initial or Resumed SSL Session.  Note: multiple requests may be served over the same (Initial or Resumed) SSL session if HTTP KeepAlive is in use</td></tr>
<tr><td><code>SSL_SECURE_RENEG</code></td>              <td>string</td>    <td><code>true</code> if secure renegotiation is supported, else <code>false</code></td></tr>
<tr><td><code>SSL_CIPHER</code></td>                    <td>string</td>    <td>The cipher specification name</td></tr>
<tr><td><code>SSL_CIPHER_EXPORT</code></td>             <td>string</td>    <td><code>true</code> if cipher is an export cipher</td></tr>
<tr><td><code>SSL_CIPHER_USEKEYSIZE</code></td>         <td>number</td>    <td>Number of cipher bits (actually used)</td></tr>
<tr><td><code>SSL_CIPHER_ALGKEYSIZE</code></td>         <td>number</td>    <td>Number of cipher bits (possible)</td></tr>
<tr><td><code>SSL_COMPRESS_METHOD</code></td>           <td>string</td>    <td>SSL compression method negotiated</td></tr>
<tr><td><code>SSL_VERSION_INTERFACE</code></td>         <td>string</td>    <td>The mod_ssl program version</td></tr>
<tr><td><code>SSL_VERSION_LIBRARY</code></td>           <td>string</td>    <td>The OpenSSL program version</td></tr>
<tr><td><code>SSL_CLIENT_M_VERSION</code></td>          <td>string</td>    <td>The version of the client certificate</td></tr>
<tr><td><code>SSL_CLIENT_M_SERIAL</code></td>           <td>string</td>    <td>The serial of the client certificate</td></tr>
<tr><td><code>SSL_CLIENT_S_DN</code></td>               <td>string</td>    <td>Subject DN in client's certificate</td></tr>
<tr><td><code>SSL_CLIENT_S_DN_</code><em>x509</em></td> <td>string</td>    <td>Component of client's Subject DN</td></tr>
<tr><td><code>SSL_CLIENT_I_DN</code></td>               <td>string</td>    <td>Issuer DN of client's certificate</td></tr>
<tr><td><code>SSL_CLIENT_I_DN_</code><em>x509</em></td> <td>string</td>    <td>Component of client's Issuer DN</td></tr>
<tr><td><code>SSL_CLIENT_V_START</code></td>            <td>string</td>    <td>Validity of client's certificate (start time)</td></tr>
<tr><td><code>SSL_CLIENT_V_END</code></td>              <td>string</td>    <td>Validity of client's certificate (end time)</td></tr>
<tr><td><code>SSL_CLIENT_V_REMAIN</code></td>           <td>string</td>    <td>Number of days until client's certificate expires</td></tr>
<tr><td><code>SSL_CLIENT_A_SIG</code></td>              <td>string</td>    <td>Algorithm used for the signature of client's certificate</td></tr>
<tr><td><code>SSL_CLIENT_A_KEY</code></td>              <td>string</td>    <td>Algorithm used for the public key of client's certificate</td></tr>
<tr><td><code>SSL_CLIENT_CERT</code></td>               <td>string</td>    <td>PEM-encoded client certificate</td></tr>
<tr><td><code>SSL_CLIENT_CERT_CHAIN_</code><em>n</em></td> <td>string</td>    <td>PEM-encoded certificates in client certificate chain</td></tr>
<tr><td><code>SSL_CLIENT_VERIFY</code></td>             <td>string</td>    <td><code>NONE</code>, <code>SUCCESS</code>, <code>GENEROUS</code> or <code>FAILED:</code><em>reason</em></td></tr>
<tr><td><code>SSL_SERVER_M_VERSION</code></td>          <td>string</td>    <td>The version of the server certificate</td></tr>
<tr><td><code>SSL_SERVER_M_SERIAL</code></td>           <td>string</td>    <td>The serial of the server certificate</td></tr>
<tr><td><code>SSL_SERVER_S_DN</code></td>               <td>string</td>    <td>Subject DN in server's certificate</td></tr>
<tr><td><code>SSL_SERVER_S_DN_</code><em>x509</em></td> <td>string</td>    <td>Component of server's Subject DN</td></tr>
<tr><td><code>SSL_SERVER_I_DN</code></td>               <td>string</td>    <td>Issuer DN of server's certificate</td></tr>
<tr><td><code>SSL_SERVER_I_DN_</code><em>x509</em></td> <td>string</td>    <td>Component of server's Issuer DN</td></tr>
<tr><td><code>SSL_SERVER_V_START</code></td>            <td>string</td>    <td>Validity of server's certificate (start time)</td></tr>
<tr><td><code>SSL_SERVER_V_END</code></td>              <td>string</td>    <td>Validity of server's certificate (end time)</td></tr>
<tr><td><code>SSL_SERVER_A_SIG</code></td>              <td>string</td>    <td>Algorithm used for the signature of server's certificate</td></tr>
<tr><td><code>SSL_SERVER_A_KEY</code></td>              <td>string</td>    <td>Algorithm used for the public key of server's certificate</td></tr>
<tr><td><code>SSL_SERVER_CERT</code></td>               <td>string</td>    <td>PEM-encoded server certificate</td></tr>
</table>

<p><em>x509</em> specifies a component of an X.509 DN; one of
<code>C,ST,L,O,OU,CN,T,I,G,S,D,UID,Email</code>.  In Apache 2.1 and
later, <em>x509</em> may also include a numeric <code>_n</code>
suffix.  If the DN in question contains multiple attributes of the
same name, this suffix is used as a zero-based index to select a
particular attribute.  For example, where the server certificate
subject DN included two OU attributes, <code>SSL_SERVER_S_DN_OU_0</code>
and
<code>SSL_SERVER_S_DN_OU_1</code> could be used to reference each.  A
variable name without a <code>_n</code> suffix is equivalent to that
name with a <code>_0</code> suffix; the first (or only) attribute.
When the environment table is populated using
the <code>StdEnvVars</code> option of
the <code class="directive"><a href="#ssloptions">SSLOptions</a></code> directive, the
first (or only) attribute of any DN is added only under a non-suffixed
name; i.e. no <code>_0</code> suffixed entries are added.</p>

<p>The format of the <em>*_DN</em> variables has changed in Apache HTTPD
2.3.11. See the <code>LegacyDNStringFormat</code> option for
<code class="directive"><a href="#ssloptions">SSLOptions</a></code> for details.</p>

<p><code>SSL_CLIENT_V_REMAIN</code> is only available in version 2.1
and later.</p>

<p>A number of additional environment variables can also be used
in <code class="directive">SSLRequire</code> expressions, or in custom log
formats:</p>

<div class="note"><pre>HTTP_USER_AGENT        PATH_INFO             AUTH_TYPE
HTTP_REFERER           QUERY_STRING          SERVER_SOFTWARE
HTTP_COOKIE            REMOTE_HOST           API_VERSION
HTTP_FORWARDED         REMOTE_IDENT          TIME_YEAR
HTTP_HOST              IS_SUBREQ             TIME_MON
HTTP_PROXY_CONNECTION  DOCUMENT_ROOT         TIME_DAY
HTTP_ACCEPT            SERVER_ADMIN          TIME_HOUR
THE_REQUEST            SERVER_NAME           TIME_MIN
REQUEST_FILENAME       SERVER_PORT           TIME_SEC
REQUEST_METHOD         SERVER_PROTOCOL       TIME_WDAY
REQUEST_SCHEME         REMOTE_ADDR           TIME
REQUEST_URI            REMOTE_USER</pre></div>

<p>In these contexts, two special formats can also be used:</p>

<dl>
  <dt><code>ENV:<em>variablename</em></code></dt>
  <dd>This will expand to the standard environment
  variable <em>variablename</em>.</dd>

  <dt><code>HTTP:<em>headername</em></code></dt>
  <dd>This will expand to the value of the request header with name
  <em>headername</em>.</dd>
</dl>

</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="logformats" id="logformats">Custom Log Formats</a></h2>

<p>When <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> is built into Apache or at least
loaded (under DSO situation) additional functions exist for the <a href="mod_log_config.html#formats">Custom Log Format</a> of
<code class="module"><a href="../mod/mod_log_config.html">mod_log_config</a></code>. First there is an
additional ``<code>%{</code><em>varname</em><code>}x</code>''
eXtension format function which can be used to expand any variables
provided by any module, especially those provided by mod_ssl which can
you find in the above table.</p>
<p>
For backward compatibility there is additionally a special
``<code>%{</code><em>name</em><code>}c</code>'' cryptography format function
provided. Information about this function is provided in the <a href="../ssl/ssl_compat.html">Compatibility</a> chapter.</p>
<div class="example"><h3>Example</h3><p><code>
CustomLog logs/ssl_request_log \
          "%t %h %{SSL_PROTOCOL}x %{SSL_CIPHER}x \"%r\" %b"
</code></p></div>
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="notes" id="notes">Request Notes</a></h2>

<p><code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> sets "notes" for the request which can be
used in logging with the <code>%{<em>name</em>}n</code> format
string in <code class="module"><a href="../mod/mod_log_config.html">mod_log_config</a></code>.</p>

<p>The notes supported are as follows:</p>

<dl>
  <dt><code>ssl-access-forbidden</code></dt>
  <dd>This note is set to the value <code>1</code> if access was
  denied due to an <code class="directive">SSLRequire</code>
  or <code class="directive">SSLRequireSSL</code> directive.</dd>

  <dt><code>ssl-secure-reneg</code></dt>
  <dd>If <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> is built against a version of
  OpenSSL which supports the secure renegotiation extension, this note
  is set to the value <code>1</code> if SSL is in used for the current
  connection, and the client also supports the secure renegotiation
  extension.  If the client does not support the secure renegotiation
  extension, the note is set to the value <code>0</code>.
  If <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> is not built against a version of
  OpenSSL which supports secure renegotiation, or if SSL is not in use
  for the current connection, the note is not set.</dd>
</dl>

</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="section">
<h2><a name="authzproviders" id="authzproviders">Authorization providers for use with Require</a></h2>

  <p><code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> provides a few authentication providers for use
  with <code class="module"><a href="../mod/mod_authz_core.html">mod_authz_core</a></code>'s
  <code class="directive"><a href="../mod/mod_authz_core.html#require">Require</a></code> directive.</p>

  <h3><a name="reqssl" id="reqssl">Require ssl</a></h3>

    <p>The <code>ssl</code> provider denies access if a connection is not
       encrypted with SSL. This is similar to the
       <code class="directive">SSLRequireSSL</code> directive.</p>

    <div class="example"><p><code>
      Require ssl
    </code></p></div>

  

  <h3><a name="reqverifyclient" id="reqverifyclient">Require ssl-verify-client</a></h3>

    <p>The <code>ssl</code> provider allows access if the user is
       authenticated with a valid client certificate. This is only
       useful if <code>SSLVerifyClient optional</code> is in effect.</p>

    <p>The following example grants access if the user is authenticated
       either with a client certificate or by username and password.</p>

    <div class="example"><p><code>
      Require ssl-verify-client<br />
      Require valid-user
    </code></p></div>

  

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCACertificateFile" id="SSLCACertificateFile">SSLCACertificateFile</a> <a name="sslcacertificatefile" id="sslcacertificatefile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File of concatenated PEM-encoded CA Certificates
for Client Auth</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCACertificateFile <em>file-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the <em>all-in-one</em> file where you can assemble the
Certificates of Certification Authorities (CA) whose <em>clients</em> you deal
with. These are used for Client Authentication. Such a file is simply the
concatenation of the various PEM-encoded Certificate files, in order of
preference. This can be used alternatively and/or additionally to
<code class="directive"><a href="#sslcacertificatepath">SSLCACertificatePath</a></code>.</p>
<div class="example"><h3>Example</h3><p><code>
SSLCACertificateFile /usr/local/apache2/conf/ssl.crt/ca-bundle-client.crt
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCACertificatePath" id="SSLCACertificatePath">SSLCACertificatePath</a> <a name="sslcacertificatepath" id="sslcacertificatepath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory of PEM-encoded CA Certificates for
Client Auth</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCACertificatePath <em>directory-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the directory where you keep the Certificates of
Certification Authorities (CAs) whose clients you deal with. These are used to
verify the client certificate on Client Authentication.</p>
<p>
The files in this directory have to be PEM-encoded and are accessed through
hash filenames. So usually you can't just place the Certificate files
there: you also have to create symbolic links named
<em>hash-value</em><code>.N</code>. And you should always make sure this directory
contains the appropriate symbolic links.</p>
<div class="example"><h3>Example</h3><p><code>
SSLCACertificatePath /usr/local/apache2/conf/ssl.crt/
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCADNRequestFile" id="SSLCADNRequestFile">SSLCADNRequestFile</a> <a name="sslcadnrequestfile" id="sslcadnrequestfile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File of concatenated PEM-encoded CA Certificates
for defining acceptable CA names</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCADNRequestFile <em>file-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>When a client certificate is requested by mod_ssl, a list of
<em>acceptable Certificate Authority names</em> is sent to the client
in the SSL handshake.  These CA names can be used by the client to
select an appropriate client certificate out of those it has
available.</p>

<p>If neither of the directives <code class="directive"><a href="#sslcadnrequestpath">SSLCADNRequestPath</a></code> or <code class="directive"><a href="#sslcadnrequestfile">SSLCADNRequestFile</a></code> are given, then the
set of acceptable CA names sent to the client is the names of all the
CA certificates given by the <code class="directive"><a href="#sslcacertificatefile">SSLCACertificateFile</a></code> and <code class="directive"><a href="#sslcacertificatepath">SSLCACertificatePath</a></code> directives; in other
words, the names of the CAs which will actually be used to verify the
client certificate.</p>

<p>In some circumstances, it is useful to be able to send a set of
acceptable CA names which differs from the actual CAs used to verify
the client certificate - for example, if the client certificates are
signed by intermediate CAs.  In such cases, <code class="directive"><a href="#sslcadnrequestpath">SSLCADNRequestPath</a></code> and/or <code class="directive"><a href="#sslcadnrequestfile">SSLCADNRequestFile</a></code> can be used; the
acceptable CA names are then taken from the complete set of
certificates in the directory and/or file specified by this pair of
directives.</p>

<p><code class="directive"><a href="#sslcadnrequestfile">SSLCADNRequestFile</a></code> must
specify an <em>all-in-one</em> file containing a concatenation of
PEM-encoded CA certificates.</p>

<div class="example"><h3>Example</h3><p><code>
SSLCADNRequestFile /usr/local/apache2/conf/ca-names.crt
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCADNRequestPath" id="SSLCADNRequestPath">SSLCADNRequestPath</a> <a name="sslcadnrequestpath" id="sslcadnrequestpath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory of PEM-encoded CA Certificates for
defining acceptable CA names</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCADNRequestPath <em>directory-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>

<p>This optional directive can be used to specify the set of
<em>acceptable CA names</em> which will be sent to the client when a
client certificate is requested.  See the <code class="directive"><a href="#sslcadnrequestfile">SSLCADNRequestFile</a></code> directive for more
details.</p>

<p>The files in this directory have to be PEM-encoded and are accessed
through hash filenames. So usually you can't just place the
Certificate files there: you also have to create symbolic links named
<em>hash-value</em><code>.N</code>. And you should always make sure
this directory contains the appropriate symbolic links.</p>
<div class="example"><h3>Example</h3><p><code>
SSLCADNRequestPath /usr/local/apache2/conf/ca-names.crt/
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCARevocationCheck" id="SSLCARevocationCheck">SSLCARevocationCheck</a> <a name="sslcarevocationcheck" id="sslcarevocationcheck">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enable CRL-based revocation checking</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCARevocationCheck chain|leaf|none</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLCARevocationCheck none</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
Enables certificate revocation list (CRL) checking. At least one of
<code class="directive"><a href="#sslcarevocationfile">SSLCARevocationFile</a></code>
or <code class="directive"><a href="#sslcarevocationpath">SSLCARevocationPath</a></code> must be
configured. When set to <code>chain</code> (recommended setting),
CRL checks are applied to all certificates in the chain, while setting it to
<code>leaf</code> limits the checks to the end-entity cert.
</p>
<div class="note">
<h3>When set to <code>chain</code> or <code>leaf</code>,
CRLs <em>must</em> be available for successful validation</h3>
<p>
Prior to version 2.3.15, CRL checking in mod_ssl also succeeded when
no CRL(s) were found in any of the locations configured with
<code class="directive"><a href="#sslcarevocationfile">SSLCARevocationFile</a></code>
or <code class="directive"><a href="#sslcarevocationpath">SSLCARevocationPath</a></code>.
With the introduction of this directive, the behavior has been changed:
when checking is enabled, CRLs <em>must</em> be present for the validation
to succeed - otherwise it will fail with an
<code>"unable to get certificate CRL"</code> error.
</p>
</div>
<div class="example"><h3>Example</h3><p><code>
SSLCARevocationCheck chain
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCARevocationFile" id="SSLCARevocationFile">SSLCARevocationFile</a> <a name="sslcarevocationfile" id="sslcarevocationfile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File of concatenated PEM-encoded CA CRLs for
Client Auth</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCARevocationFile <em>file-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the <em>all-in-one</em> file where you can
assemble the Certificate Revocation Lists (CRL) of Certification
Authorities (CA) whose <em>clients</em> you deal with. These are used
for Client Authentication.  Such a file is simply the concatenation of
the various PEM-encoded CRL files, in order of preference. This can be
used alternatively and/or additionally to <code class="directive"><a href="#sslcarevocationpath">SSLCARevocationPath</a></code>.</p>
<div class="example"><h3>Example</h3><p><code>
SSLCARevocationFile /usr/local/apache2/conf/ssl.crl/ca-bundle-client.crl
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCARevocationPath" id="SSLCARevocationPath">SSLCARevocationPath</a> <a name="sslcarevocationpath" id="sslcarevocationpath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory of PEM-encoded CA CRLs for
Client Auth</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCARevocationPath <em>directory-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the directory where you keep the Certificate Revocation
Lists (CRL) of Certification Authorities (CAs) whose clients you deal with.
These are used to revoke the client certificate on Client Authentication.</p>
<p>
The files in this directory have to be PEM-encoded and are accessed through
hash filenames. So usually you have not only to place the CRL files there.
Additionally you have to create symbolic links named
<em>hash-value</em><code>.rN</code>. And you should always make sure this directory
contains the appropriate symbolic links.</p>
<div class="example"><h3>Example</h3><p><code>
SSLCARevocationPath /usr/local/apache2/conf/ssl.crl/
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCertificateChainFile" id="SSLCertificateChainFile">SSLCertificateChainFile</a> <a name="sslcertificatechainfile" id="sslcertificatechainfile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File of PEM-encoded Server CA Certificates</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCertificateChainFile <em>file-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the optional <em>all-in-one</em> file where you can
assemble the certificates of Certification Authorities (CA) which form the
certificate chain of the server certificate. This starts with the issuing CA
certificate of the server certificate and can range up to the root CA
certificate. Such a file is simply the concatenation of the various
PEM-encoded CA Certificate files, usually in certificate chain order.</p>
<p>
This should be used alternatively and/or additionally to <code class="directive"><a href="#sslcacertificatepath">SSLCACertificatePath</a></code> for explicitly
constructing the server certificate chain which is sent to the browser
in addition to the server certificate. It is especially useful to
avoid conflicts with CA certificates when using client
authentication. Because although placing a CA certificate of the
server certificate chain into <code class="directive"><a href="#sslcacertificatepath">SSLCACertificatePath</a></code> has the same effect
for the certificate chain construction, it has the side-effect that
client certificates issued by this same CA certificate are also
accepted on client authentication.</p>
<p>
But be careful: Providing the certificate chain works only if you are using a
<em>single</em> RSA <em>or</em> DSA based server certificate. If you are
using a coupled RSA+DSA certificate pair, this will work only if actually both
certificates use the <em>same</em> certificate chain. Else the browsers will be
confused in this situation.</p>
<div class="example"><h3>Example</h3><p><code>
SSLCertificateChainFile /usr/local/apache2/conf/ssl.crt/ca.crt
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCertificateFile" id="SSLCertificateFile">SSLCertificateFile</a> <a name="sslcertificatefile" id="sslcertificatefile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Server PEM-encoded X.509 Certificate file</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCertificateFile <em>file-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive points to the PEM-encoded Certificate file for the server and
optionally also to the corresponding RSA or DSA Private Key file for it
(contained in the same file). If the contained Private Key is encrypted the
Pass Phrase dialog is forced at startup time. This directive can be used up to
two times (referencing different filenames) when both a RSA and a DSA based
server certificate is used in parallel.</p>
<div class="example"><h3>Example</h3><p><code>
SSLCertificateFile /usr/local/apache2/conf/ssl.crt/server.crt
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCertificateKeyFile" id="SSLCertificateKeyFile">SSLCertificateKeyFile</a> <a name="sslcertificatekeyfile" id="sslcertificatekeyfile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Server PEM-encoded Private Key file</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCertificateKeyFile <em>file-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive points to the PEM-encoded Private Key file for the
server. If the Private Key is not combined with the Certificate in the
<code class="directive">SSLCertificateFile</code>, use this additional directive to
point to the file with the stand-alone Private Key. When
<code class="directive">SSLCertificateFile</code> is used and the file
contains both the Certificate and the Private Key this directive need
not be used. But we strongly discourage this practice.  Instead we
recommend you to separate the Certificate and the Private Key. If the
contained Private Key is encrypted, the Pass Phrase dialog is forced
at startup time. This directive can be used up to two times
(referencing different filenames) when both a RSA and a DSA based
private key is used in parallel.</p>
<div class="example"><h3>Example</h3><p><code>
SSLCertificateKeyFile /usr/local/apache2/conf/ssl.key/server.key
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCipherSuite" id="SSLCipherSuite">SSLCipherSuite</a> <a name="sslciphersuite" id="sslciphersuite">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Cipher Suite available for negotiation in SSL
handshake</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCipherSuite <em>cipher-spec</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLCipherSuite DEFAULT (depends on OpenSSL version)</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This complex directive uses a colon-separated <em>cipher-spec</em> string
consisting of OpenSSL cipher specifications to configure the Cipher Suite the
client is permitted to negotiate in the SSL handshake phase. Notice that this
directive can be used both in per-server and per-directory context. In
per-server context it applies to the standard SSL handshake when a connection
is established. In per-directory context it forces a SSL renegotiation with the
reconfigured Cipher Suite after the HTTP request was read but before the HTTP
response is sent.</p>
<p>
An SSL cipher specification in <em>cipher-spec</em> is composed of 4 major
attributes plus a few extra minor ones:</p>
<ul>
<li><em>Key Exchange Algorithm</em>:<br />
    RSA or Diffie-Hellman variants.
</li>
<li><em>Authentication Algorithm</em>:<br />
    RSA, Diffie-Hellman, DSS or none.
</li>
<li><em>Cipher/Encryption Algorithm</em>:<br />
    DES, Triple-DES, RC4, RC2, IDEA or none.
</li>
<li><em>MAC Digest Algorithm</em>:<br />
    MD5, SHA or SHA1.
</li>
</ul>
<p>An SSL cipher can also be an export cipher and is either an SSLv2 or SSLv3/TLSv1
cipher (here TLSv1 is equivalent to SSLv3). To specify which ciphers to use,
one can either specify all the Ciphers, one at a time, or use aliases to
specify the preference and order for the ciphers (see <a href="#table1">Table
1</a>).</p>

<table class="bordered">

<tr><th><a name="table1">Tag</a></th> <th>Description</th></tr>
<tr><td colspan="2"><em>Key Exchange Algorithm:</em></td></tr>
<tr><td><code>kRSA</code></td>   <td>RSA key exchange</td></tr>
<tr><td><code>kDHr</code></td>   <td>Diffie-Hellman key exchange with RSA key</td></tr>
<tr><td><code>kDHd</code></td>   <td>Diffie-Hellman key exchange with DSA key</td></tr>
<tr><td><code>kEDH</code></td>   <td>Ephemeral (temp.key) Diffie-Hellman key exchange (no cert)</td>   </tr>
<tr><td colspan="2"><em>Authentication Algorithm:</em></td></tr>
<tr><td><code>aNULL</code></td>  <td>No authentication</td></tr>
<tr><td><code>aRSA</code></td>   <td>RSA authentication</td></tr>
<tr><td><code>aDSS</code></td>   <td>DSS authentication</td> </tr>
<tr><td><code>aDH</code></td>    <td>Diffie-Hellman authentication</td></tr>
<tr><td colspan="2"><em>Cipher Encoding Algorithm:</em></td></tr>
<tr><td><code>eNULL</code></td>  <td>No encoding</td>         </tr>
<tr><td><code>DES</code></td>    <td>DES encoding</td>        </tr>
<tr><td><code>3DES</code></td>   <td>Triple-DES encoding</td> </tr>
<tr><td><code>RC4</code></td>    <td>RC4 encoding</td>       </tr>
<tr><td><code>RC2</code></td>    <td>RC2 encoding</td>       </tr>
<tr><td><code>IDEA</code></td>   <td>IDEA encoding</td>       </tr>
<tr><td colspan="2"><em>MAC Digest Algorithm</em>:</td></tr>
<tr><td><code>MD5</code></td>    <td>MD5 hash function</td></tr>
<tr><td><code>SHA1</code></td>   <td>SHA1 hash function</td></tr>
<tr><td><code>SHA</code></td>    <td>SHA hash function</td> </tr>
<tr><td colspan="2"><em>Aliases:</em></td></tr>
<tr><td><code>SSLv2</code></td>  <td>all SSL version 2.0 ciphers</td></tr>
<tr><td><code>SSLv3</code></td>  <td>all SSL version 3.0 ciphers</td> </tr>
<tr><td><code>TLSv1</code></td>  <td>all TLS version 1.0 ciphers</td> </tr>
<tr><td><code>EXP</code></td>    <td>all export ciphers</td>  </tr>
<tr><td><code>EXPORT40</code></td> <td>all 40-bit export ciphers only</td>  </tr>
<tr><td><code>EXPORT56</code></td> <td>all 56-bit export ciphers only</td>  </tr>
<tr><td><code>LOW</code></td>    <td>all low strength ciphers (no export, single DES)</td></tr>
<tr><td><code>MEDIUM</code></td> <td>all ciphers with 128 bit encryption</td> </tr>
<tr><td><code>HIGH</code></td>   <td>all ciphers using Triple-DES</td>     </tr>
<tr><td><code>RSA</code></td>    <td>all ciphers using RSA key exchange</td> </tr>
<tr><td><code>DH</code></td>     <td>all ciphers using Diffie-Hellman key exchange</td> </tr>
<tr><td><code>EDH</code></td>    <td>all ciphers using Ephemeral Diffie-Hellman key exchange</td> </tr>
<tr><td><code>ADH</code></td>    <td>all ciphers using Anonymous Diffie-Hellman key exchange</td> </tr>
<tr><td><code>DSS</code></td>    <td>all ciphers using DSS authentication</td> </tr>
<tr><td><code>NULL</code></td>   <td>all ciphers using no encryption</td> </tr>
</table>
<p>
Now where this becomes interesting is that these can be put together
to specify the order and ciphers you wish to use. To speed this up
there are also aliases (<code>SSLv2, SSLv3, TLSv1, EXP, LOW, MEDIUM,
HIGH</code>) for certain groups of ciphers. These tags can be joined
together with prefixes to form the <em>cipher-spec</em>. Available
prefixes are:</p>
<ul>
<li>none: add cipher to list</li>
<li><code>+</code>: add ciphers to list and pull them to current location in list</li>
<li><code>-</code>: remove cipher from list (can be added later again)</li>
<li><code>!</code>: kill cipher from list completely (can <strong>not</strong> be added later again)</li>
</ul>
<p>A simpler way to look at all of this is to use the ``<code>openssl ciphers
-v</code>'' command which provides a nice way to successively create the
correct <em>cipher-spec</em> string. The default <em>cipher-spec</em> string
depends on the version of the OpenSSL libraries used. Let's suppose it is
``<code>ALL:!aNULL:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP</code>'' which
means the following: first, remove from consideration any ciphers that do not
authenticate, i.e. for SSL the Anonymous Diffie-Hellman ciphers. Next,
use ciphers using RC4 and RSA. Next include the high, medium and then the low
security ciphers. Finally <em>pull</em> all SSLv2 and export ciphers to the
end of the list.</p>
<div class="example"><pre>
$ openssl ciphers -v 'ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP'
NULL-SHA                SSLv3 Kx=RSA      Au=RSA  Enc=None      Mac=SHA1
NULL-MD5                SSLv3 Kx=RSA      Au=RSA  Enc=None      Mac=MD5
EDH-RSA-DES-CBC3-SHA    SSLv3 Kx=DH       Au=RSA  Enc=3DES(168) Mac=SHA1
...                     ...               ...     ...           ...
EXP-RC4-MD5             SSLv3 Kx=RSA(512) Au=RSA  Enc=RC4(40)   Mac=MD5  export
EXP-RC2-CBC-MD5         SSLv2 Kx=RSA(512) Au=RSA  Enc=RC2(40)   Mac=MD5  export
EXP-RC4-MD5             SSLv2 Kx=RSA(512) Au=RSA  Enc=RC4(40)   Mac=MD5  export
</pre></div>
<p>The complete list of particular RSA &amp; DH ciphers for SSL is given in <a href="#table2">Table 2</a>.</p>
<div class="example"><h3>Example</h3><p><code>
SSLCipherSuite RSA:!EXP:!NULL:+HIGH:+MEDIUM:-LOW
</code></p></div>
<table class="bordered">

<tr><th><a name="table2">Cipher-Tag</a></th> <th>Protocol</th> <th>Key Ex.</th> <th>Auth.</th> <th>Enc.</th> <th>MAC</th> <th>Type</th> </tr>
<tr><td colspan="7"><em>RSA Ciphers:</em></td></tr>
<tr><td><code>DES-CBC3-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>3DES(168)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>DES-CBC3-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>3DES(168)</td> <td>MD5</td> <td /> </tr>
<tr><td><code>IDEA-CBC-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>IDEA(128)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>RC4-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>RC4(128)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>RC4-MD5</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>RC4(128)</td> <td>MD5</td> <td /> </tr>
<tr><td><code>IDEA-CBC-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>IDEA(128)</td> <td>MD5</td> <td /> </tr>
<tr><td><code>RC2-CBC-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>RC2(128)</td> <td>MD5</td> <td /> </tr>
<tr><td><code>RC4-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>RC4(128)</td> <td>MD5</td> <td /> </tr>
<tr><td><code>DES-CBC-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>DES(56)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>RC4-64-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>RC4(64)</td> <td>MD5</td> <td /> </tr>
<tr><td><code>DES-CBC-MD5</code></td> <td>SSLv2</td> <td>RSA</td> <td>RSA</td> <td>DES(56)</td> <td>MD5</td> <td /> </tr>
<tr><td><code>EXP-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>RSA(512)</td> <td>RSA</td> <td>DES(40)</td> <td>SHA1</td> <td> export</td> </tr>
<tr><td><code>EXP-RC2-CBC-MD5</code></td> <td>SSLv3</td> <td>RSA(512)</td> <td>RSA</td> <td>RC2(40)</td> <td>MD5</td> <td>  export</td> </tr>
<tr><td><code>EXP-RC4-MD5</code></td> <td>SSLv3</td> <td>RSA(512)</td> <td>RSA</td> <td>RC4(40)</td> <td>MD5</td> <td>  export</td> </tr>
<tr><td><code>EXP-RC2-CBC-MD5</code></td> <td>SSLv2</td> <td>RSA(512)</td> <td>RSA</td> <td>RC2(40)</td> <td>MD5</td> <td>  export</td> </tr>
<tr><td><code>EXP-RC4-MD5</code></td> <td>SSLv2</td> <td>RSA(512)</td> <td>RSA</td> <td>RC4(40)</td> <td>MD5</td> <td>  export</td> </tr>
<tr><td><code>NULL-SHA</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>None</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>NULL-MD5</code></td> <td>SSLv3</td> <td>RSA</td> <td>RSA</td> <td>None</td> <td>MD5</td> <td /> </tr>
<tr><td colspan="7"><em>Diffie-Hellman Ciphers:</em></td></tr>
<tr><td><code>ADH-DES-CBC3-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>None</td> <td>3DES(168)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>ADH-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>None</td> <td>DES(56)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>ADH-RC4-MD5</code></td> <td>SSLv3</td> <td>DH</td> <td>None</td> <td>RC4(128)</td> <td>MD5</td> <td /> </tr>
<tr><td><code>EDH-RSA-DES-CBC3-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>RSA</td> <td>3DES(168)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>EDH-DSS-DES-CBC3-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>DSS</td> <td>3DES(168)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>EDH-RSA-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>RSA</td> <td>DES(56)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>EDH-DSS-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH</td> <td>DSS</td> <td>DES(56)</td> <td>SHA1</td> <td /> </tr>
<tr><td><code>EXP-EDH-RSA-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH(512)</td> <td>RSA</td> <td>DES(40)</td> <td>SHA1</td> <td> export</td> </tr>
<tr><td><code>EXP-EDH-DSS-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH(512)</td> <td>DSS</td> <td>DES(40)</td> <td>SHA1</td> <td> export</td> </tr>
<tr><td><code>EXP-ADH-DES-CBC-SHA</code></td> <td>SSLv3</td> <td>DH(512)</td> <td>None</td> <td>DES(40)</td> <td>SHA1</td> <td> export</td> </tr>
<tr><td><code>EXP-ADH-RC4-MD5</code></td> <td>SSLv3</td> <td>DH(512)</td> <td>None</td> <td>RC4(40)</td> <td>MD5</td> <td>  export</td> </tr>
</table>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLCryptoDevice" id="SSLCryptoDevice">SSLCryptoDevice</a> <a name="sslcryptodevice" id="sslcryptodevice">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enable use of a cryptographic hardware accelerator</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLCryptoDevice <em>engine</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLCryptoDevice builtin</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive enables use of a cryptographic hardware accelerator
board to offload some of the SSL processing overhead.  This directive
can only be used if the SSL toolkit is built with "engine" support;
OpenSSL 0.9.7 and later releases have "engine" support by default, the
separate "-engine" releases of OpenSSL 0.9.6 must be used.</p>

<p>To discover which engine names are supported, run the command
"<code>openssl engine</code>".</p>

<div class="example"><h3>Example</h3><p><code>
# For a Broadcom accelerator:<br />
SSLCryptoDevice ubsec
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLEngine" id="SSLEngine">SSLEngine</a> <a name="sslengine" id="sslengine">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>SSL Engine Operation Switch</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLEngine on|off|optional</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLEngine off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive toggles the usage of the SSL/TLS Protocol Engine. This
is should be used inside a <code class="directive"><a href="../mod/core.html#virtualhost">&lt;VirtualHost&gt;</a></code> section to enable SSL/TLS for a
that virtual host. By default the SSL/TLS Protocol Engine is
disabled for both the main server and all configured virtual hosts.</p>
<div class="example"><h3>Example</h3><p><code>
&lt;VirtualHost _default_:443&gt;<br />
SSLEngine on<br />
...<br />
&lt;/VirtualHost&gt;
</code></p></div>
<p>In Apache 2.1 and later, <code class="directive">SSLEngine</code> can be set to
<code>optional</code>. This enables support for
<a href="http://www.ietf.org/rfc/rfc2817.txt">RFC 2817</a>, Upgrading to TLS
Within HTTP/1.1. At this time no web browsers support RFC 2817.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLFIPS" id="SSLFIPS">SSLFIPS</a> <a name="sslfips" id="sslfips">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>SSL FIPS mode Switch</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLFIPS on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLFIPS off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive toggles the usage of the SSL library FIPS_mode flag.
It must be set in the global server context and cannot be configured
with conflicting settings (SSLFIPS on followed by SSLFIPS off or
similar).  The mode applies to all SSL library operations.
</p>
<p>
If httpd was compiled against an SSL library which did not support
the FIPS_mode flag, <code>SSLFIPS on</code> will fail.  Refer to the
FIPS 140-2 Security Policy document of the SSL provider library for
specific requirements to use mod_ssl in a FIPS 140-2 approved mode
of operation; note that mod_ssl itself is not validated, but may be
described as using FIPS 140-2 validated cryptographic module, when
all components are assembled and operated under the guidelines imposed
by the applicable Security Policy.
</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLHonorCipherOrder" id="SSLHonorCipherOrder">SSLHonorCipherOrder</a> <a name="sslhonorcipherorder" id="sslhonorcipherorder">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Option to prefer the server's cipher preference order</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLHonorCipherOrder <em>flag</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.1 and later, if using OpenSSL 0.9.7 or later</td></tr>
</table>
<p>When choosing a cipher during an SSLv3 or TLSv1 handshake, normally
the client's preference is used.  If this directive is enabled, the
server's preference will be used instead.</p>
<div class="example"><h3>Example</h3><p><code>
SSLHonorCipherOrder on
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLInsecureRenegotiation" id="SSLInsecureRenegotiation">SSLInsecureRenegotiation</a> <a name="sslinsecurerenegotiation" id="sslinsecurerenegotiation">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Option to enable support for insecure renegotiation</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLInsecureRenegotiation <em>flag</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLInsecureRenegotiation off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.2.15 and later, if using OpenSSL 0.9.8m or later</td></tr>
</table>
<p>As originally specified, all versions of the SSL and TLS protocols
(up to and including TLS/1.2) were vulnerable to a Man-in-the-Middle
attack
(<a href="http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2009-3555">CVE-2009-3555</a>)
during a renegotiation.  This vulnerability allowed an attacker to
"prefix" a chosen plaintext to the HTTP request as seen by the web
server.  A protocol extension was developed which fixed this
vulnerability if supported by both client and server.</p>

<p>If <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> is linked against OpenSSL version 0.9.8m
or later, by default renegotiation is only supported with
clients supporting the new protocol extension.  If this directive is
enabled, renegotiation will be allowed with old (unpatched) clients,
albeit insecurely.</p>

<div class="warning"><h3>Security warning</h3>
<p>If this directive is enabled, SSL connections will be vulnerable to
the Man-in-the-Middle prefix attack as described
in <a href="http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2009-3555">CVE-2009-3555</a>.</p>
</div>

<div class="example"><h3>Example</h3><p><code>
SSLInsecureRenegotiation on
</code></p></div>

<p>The <code>SSL_SECURE_RENEG</code> environment variable can be used
from an SSI or CGI script to determine whether secure renegotiation is
supported for a given SSL connection.</p>


</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLOCSPDefaultResponder" id="SSLOCSPDefaultResponder">SSLOCSPDefaultResponder</a> <a name="sslocspdefaultresponder" id="sslocspdefaultresponder">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Set the default responder URI for OCSP validation</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLOCSDefaultResponder <em>uri</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3 and later, if using OpenSSL 0.9.7 or later</td></tr>
</table>
<p>This option sets the default OCSP responder to use.  If <code class="directive"><a href="#sslocspoverrideresponder">SSLOCSPOverrideResponder</a></code> is not enabled,
the URI given will be used only if no responder URI is specified in
the certificate being verified.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLOCSPEnable" id="SSLOCSPEnable">SSLOCSPEnable</a> <a name="sslocspenable" id="sslocspenable">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enable OCSP validation of the client certificate chain</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLOCSPEnable <em>flag</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3 and later, if using OpenSSL 0.9.7 or later</td></tr>
</table>
<p>This option enables OCSP validation of the client certificate
chain.  If this option is enabled, certificates in the client's
certificate chain will be validated against an OCSP responder after
normal verification (including CRL checks) have taken place.</p>

<p>The OCSP responder used is either extracted from the certificate
itself, or derived by configuration; see the
<code class="directive"><a href="#sslocspdefaultresponder">SSLOCSPDefaultResponder</a></code> and
<code class="directive"><a href="#sslocspoverrideresponder">SSLOCSPOverrideResponder</a></code>
directives.</p>

<div class="example"><h3>Example</h3><p><code>
SSLVerifyClient on<br />
SSLOCSPEnable on<br />
SSLOCSPDefaultResponder http://responder.example.com:8888/responder<br />
SSLOCSPOverrideResponder on
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLOCSPOverrideResponder" id="SSLOCSPOverrideResponder">SSLOCSPOverrideResponder</a> <a name="sslocspoverrideresponder" id="sslocspoverrideresponder">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Force use of the default responder URI for OCSP validation</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLOCSPOverrideResponder <em>flag</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3 and later, if using OpenSSL 0.9.7 or later</td></tr>
</table>
<p>This option forces the configured default OCSP responder to be used
during OCSP certificate validation, regardless of whether the
certificate being validated references an OCSP responder.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLOCSPResponderTimeout" id="SSLOCSPResponderTimeout">SSLOCSPResponderTimeout</a> <a name="sslocsprespondertimeout" id="sslocsprespondertimeout">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Timeout for OCSP queries</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLOCSPResponderTimeout <em>seconds</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLOCSPResponderTimeout 10</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3 and later, if using OpenSSL 0.9.7 or later</td></tr>
</table>
<p>This option sets the timeout for queries to OCSP responders, when
<code class="directive"><a href="#sslocspenable">SSLOCSPEnable</a></code> is turned on.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLOCSPResponseMaxAge" id="SSLOCSPResponseMaxAge">SSLOCSPResponseMaxAge</a> <a name="sslocspresponsemaxage" id="sslocspresponsemaxage">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum allowable age for OCSP responses</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLOCSPResponseMaxAge <em>seconds</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLOCSPResponseMaxAge -1</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3 and later, if using OpenSSL 0.9.7 or later</td></tr>
</table>
<p>This option sets the maximum allowable age ("freshness") for OCSP responses.
The default value (<code>-1</code>) does not enforce a maximum age,
which means that OCSP responses are considered valid as long as their
<code>nextUpdate</code> field is in the future.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLOCSPResponseTimeSkew" id="SSLOCSPResponseTimeSkew">SSLOCSPResponseTimeSkew</a> <a name="sslocspresponsetimeskew" id="sslocspresponsetimeskew">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum allowable time skew for OCSP response validation</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLOCSPResponseTimeSkew <em>seconds</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLOCSPResponseTimeSkew 300</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3 and later, if using OpenSSL 0.9.7 or later</td></tr>
</table>
<p>This option sets the maximum allowable time skew for OCSP responses
(when checking their <code>thisUpdate</code> and <code>nextUpdate</code> fields).</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLOptions" id="SSLOptions">SSLOptions</a> <a name="ssloptions" id="ssloptions">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configure various SSL engine run-time options</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLOptions [+|-]<em>option</em> ...</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Options</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive can be used to control various run-time options on a
per-directory basis. Normally, if multiple <code>SSLOptions</code>
could apply to a directory, then the most specific one is taken
completely; the options are not merged. However if <em>all</em> the
options on the <code>SSLOptions</code> directive are preceded by a
plus (<code>+</code>) or minus (<code>-</code>) symbol, the options
are merged. Any options preceded by a <code>+</code> are added to the
options currently in force, and any options preceded by a
<code>-</code> are removed from the options currently in force.</p>
<p>
The available <em>option</em>s are:</p>
<ul>
<li><code>StdEnvVars</code>
    <p>
    When this option is enabled, the standard set of SSL related CGI/SSI
    environment variables are created. This per default is disabled for
    performance reasons, because the information extraction step is a
    rather expensive operation. So one usually enables this option for
    CGI and SSI requests only.</p>
</li>
<li><code>ExportCertData</code>
    <p>
    When this option is enabled, additional CGI/SSI environment variables are
    created: <code>SSL_SERVER_CERT</code>, <code>SSL_CLIENT_CERT</code> and
    <code>SSL_CLIENT_CERT_CHAIN_</code><em>n</em> (with <em>n</em> = 0,1,2,..).
    These contain the PEM-encoded X.509 Certificates of server and client for
    the current HTTPS connection and can be used by CGI scripts for deeper
    Certificate checking. Additionally all other certificates of the client
    certificate chain are provided, too. This bloats up the environment a
    little bit which is why you have to use this option to enable it on
    demand.</p>
</li>
<li><code>FakeBasicAuth</code>
    <p>
    When this option is enabled, the Subject Distinguished Name (DN) of the
    Client X509 Certificate is translated into a HTTP Basic Authorization
    username. This means that the standard Apache authentication methods can
    be used for access control. The user name is just the Subject of the
    Client's X509 Certificate (can be determined by running OpenSSL's
    <code>openssl x509</code> command: <code>openssl x509 -noout -subject -in
    </code><em>certificate</em><code>.crt</code>). Note that no password is
    obtained from the user. Every entry in the user file needs this password:
    ``<code>xxj31ZMTZzkVA</code>'', which is the DES-encrypted version of the
    word `<code>password</code>''. Those who live under MD5-based encryption
    (for instance under FreeBSD or BSD/OS, etc.) should use the following MD5
    hash of the same word: ``<code>$1$OXLyS...$Owx8s2/m9/gfkcRVXzgoE/</code>''.</p>
</li>
<li><code>StrictRequire</code>
    <p>
    This <em>forces</em> forbidden access when <code>SSLRequireSSL</code> or
    <code>SSLRequire</code> successfully decided that access should be
    forbidden. Usually the default is that in the case where a ``<code>Satisfy
    any</code>'' directive is used, and other access restrictions are passed,
    denial of access due to <code>SSLRequireSSL</code> or
    <code>SSLRequire</code> is overridden (because that's how the Apache
    <code>Satisfy</code> mechanism should work.) But for strict access restriction
    you can use <code>SSLRequireSSL</code> and/or <code>SSLRequire</code> in
    combination with an ``<code>SSLOptions +StrictRequire</code>''. Then an
    additional ``<code>Satisfy Any</code>'' has no chance once mod_ssl has
    decided to deny access.</p>
</li>
<li><code>OptRenegotiate</code>
    <p>
    This enables optimized SSL connection renegotiation handling when SSL
    directives are used in per-directory context. By default a strict
    scheme is enabled where <em>every</em> per-directory reconfiguration of
    SSL parameters causes a <em>full</em> SSL renegotiation handshake. When this
    option is used mod_ssl tries to avoid unnecessary handshakes by doing more
    granular (but still safe) parameter checks. Nevertheless these granular
    checks sometimes maybe not what the user expects, so enable this on a
    per-directory basis only, please.</p>
</li>
<li><code>LegacyDNStringFormat</code>
    <p>
    This option influences how values of the
    <code>SSL_{CLIENT,SERVER}_{I,S}_DN</code> variables are formatted. Since
    version 2.3.11, Apache HTTPD uses a RFC 2253 compatible format by
    default. This uses commas as delimiters between the attributes, allows the
    use of non-ASCII characters (which are converted to UTF8), escapes
    various special characters with backslashes, and sorts the attributes
    with the "C" attribute last.</p>

    <p>If <code>LegacyDNStringFormat</code> is set, the old format will be
    used which sorts the "C" attribute first, uses slashes as separators, and
    does not handle non-ASCII and special characters in any consistent way.
    </p>
</li>
</ul>
<div class="example"><h3>Example</h3><p><code>
SSLOptions +FakeBasicAuth -StrictRequire<br />
&lt;Files ~ "\.(cgi|shtml)$"&gt;<br />
    SSLOptions +StdEnvVars -ExportCertData<br />
&lt;Files&gt;
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLPassPhraseDialog" id="SSLPassPhraseDialog">SSLPassPhraseDialog</a> <a name="sslpassphrasedialog" id="sslpassphrasedialog">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Type of pass phrase dialog for encrypted private
keys</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLPassPhraseDialog <em>type</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLPassPhraseDialog builtin</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
When Apache starts up it has to read the various Certificate (see
<code class="directive"><a href="#sslcertificatefile">SSLCertificateFile</a></code>) and
Private Key (see <code class="directive"><a href="#sslcertificatekeyfile">SSLCertificateKeyFile</a></code>) files of the
SSL-enabled virtual servers. Because for security reasons the Private
Key files are usually encrypted, mod_ssl needs to query the
administrator for a Pass Phrase in order to decrypt those files. This
query can be done in two ways which can be configured by
<em>type</em>:</p>
<ul>
<li><code>builtin</code>
    <p>
    This is the default where an interactive terminal dialog occurs at startup
    time just before Apache detaches from the terminal. Here the administrator
    has to manually enter the Pass Phrase for each encrypted Private Key file.
    Because a lot of SSL-enabled virtual hosts can be configured, the
    following reuse-scheme is used to minimize the dialog: When a Private Key
    file is encrypted, all known Pass Phrases (at the beginning there are
    none, of course) are tried. If one of those known Pass Phrases succeeds no
    dialog pops up for this particular Private Key file. If none succeeded,
    another Pass Phrase is queried on the terminal and remembered for the next
    round (where it perhaps can be reused).</p>
    <p>
    This scheme allows mod_ssl to be maximally flexible (because for N encrypted
    Private Key files you <em>can</em> use N different Pass Phrases - but then
    you have to enter all of them, of course) while minimizing the terminal
    dialog (i.e. when you use a single Pass Phrase for all N Private Key files
    this Pass Phrase is queried only once).</p></li>

<li><code>|/path/to/program [args...]</code>

   <p>This mode allows an external program to be used which acts as a
   pipe to a particular input device; the program is sent the standard
   prompt text used for the <code>builtin</code> mode on
   <code>stdin</code>, and is expected to write password strings on
   <code>stdout</code>.  If several passwords are needed (or an
   incorrect password is entered), additional prompt text will be
   written subsequent to the first password being returned, and more
   passwords must then be written back.</p></li>

<li><code>exec:/path/to/program</code>
    <p>
    Here an external program is configured which is called at startup for each
    encrypted Private Key file. It is called with two arguments (the first is
    of the form ``<code>servername:portnumber</code>'', the second is either
    ``<code>RSA</code>'' or ``<code>DSA</code>''), which indicate for which
    server and algorithm it has to print the corresponding Pass Phrase to
    <code>stdout</code>. The intent is that this external program first runs
    security checks to make sure that the system is not compromised by an
    attacker, and only when these checks were passed successfully it provides
    the Pass Phrase.</p>
    <p>
    Both these security checks, and the way the Pass Phrase is determined, can
    be as complex as you like. Mod_ssl just defines the interface: an
    executable program which provides the Pass Phrase on <code>stdout</code>.
    Nothing more or less! So, if you're really paranoid about security, here
    is your interface. Anything else has to be left as an exercise to the
    administrator, because local security requirements are so different.</p>
    <p>
    The reuse-algorithm above is used here, too. In other words: The external
    program is called only once per unique Pass Phrase.</p></li>
</ul>
<div class="example"><h3>Example</h3><p><code>
SSLPassPhraseDialog exec:/usr/local/apache/sbin/pp-filter
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProtocol" id="SSLProtocol">SSLProtocol</a> <a name="sslprotocol" id="sslprotocol">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configure usable SSL/TLS protocol versions</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProtocol [+|-]<em>protocol</em> ...</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLProtocol all</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive can be used to control which versions of the SSL/TLS protocol
will be accepted in new connections.</p>
<p>
The available (case-insensitive) <em>protocol</em>s are:</p>
<ul>
<li><code>SSLv3</code>
    <p>
    This is the Secure Sockets Layer (SSL) protocol, version 3.0, from
    the Netscape Corporation.
    It is the successor to SSLv2 and the predecessor to TLSv1. It's supported by
    almost all popular browsers.</p></li>

<li><code>TLSv1</code>
    <p>
    This is the Transport Layer Security (TLS) protocol, version 1.0.
    It is the successor to SSLv3 and is defined in
    <a href="http://www.ietf.org/rfc/rfc2246.txt">RFC 2246</a>.</p></li>

<li><code>TLSv1.1</code> (when using OpenSSL 1.0.1 and later)
    <p>
    A revision of the TLS 1.0 protocol, as defined in
    <a href="http://www.ietf.org/rfc/rfc4346.txt">RFC 4346</a>.</p></li>

<li><code>TLSv1.2</code> (when using OpenSSL 1.0.1 and later)
    <p>
    A revision of the TLS 1.1 protocol, as defined in
    <a href="http://www.ietf.org/rfc/rfc5246.txt">RFC 5246</a>.</p></li>

<li><code>all</code>
    <p>
    This is a shortcut for ``<code>+SSLv3 +TLSv1</code>'' or
    - when using OpenSSL 1.0.1 and later -
    ``<code>+SSLv3 +TLSv1 +TLSv1.1 +TLSv1.2</code>, respectively.</p></li>
</ul>
<div class="example"><h3>Example</h3><p><code>
SSLProtocol TLSv1
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyCACertificateFile" id="SSLProxyCACertificateFile">SSLProxyCACertificateFile</a> <a name="sslproxycacertificatefile" id="sslproxycacertificatefile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File of concatenated PEM-encoded CA Certificates
for Remote Server Auth</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyCACertificateFile <em>file-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the <em>all-in-one</em> file where you can assemble the
Certificates of Certification Authorities (CA) whose <em>remote servers</em> you deal
with. These are used for Remote Server Authentication. Such a file is simply the
concatenation of the various PEM-encoded Certificate files, in order of
preference. This can be used alternatively and/or additionally to
<code class="directive"><a href="#sslproxycacertificatepath">SSLProxyCACertificatePath</a></code>.</p>
<div class="example"><h3>Example</h3><p><code>
SSLProxyCACertificateFile /usr/local/apache2/conf/ssl.crt/ca-bundle-remote-server.crt
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyCACertificatePath" id="SSLProxyCACertificatePath">SSLProxyCACertificatePath</a> <a name="sslproxycacertificatepath" id="sslproxycacertificatepath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory of PEM-encoded CA Certificates for
Remote Server Auth</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyCACertificatePath <em>directory-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the directory where you keep the Certificates of
Certification Authorities (CAs) whose remote servers you deal with. These are used to
verify the remote server certificate on Remote Server Authentication.</p>
<p>
The files in this directory have to be PEM-encoded and are accessed through
hash filenames. So usually you can't just place the Certificate files
there: you also have to create symbolic links named
<em>hash-value</em><code>.N</code>. And you should always make sure this directory
contains the appropriate symbolic links.</p>
<div class="example"><h3>Example</h3><p><code>
SSLProxyCACertificatePath /usr/local/apache2/conf/ssl.crt/
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyCARevocationCheck" id="SSLProxyCARevocationCheck">SSLProxyCARevocationCheck</a> <a name="sslproxycarevocationcheck" id="sslproxycarevocationcheck">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enable CRL-based revocation checking for Remote Server Auth</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyCARevocationCheck chain|leaf|none</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLProxyCARevocationCheck none</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
Enables certificate revocation list (CRL) checking for the
<em>remote servers</em> you deal with. At least one of
<code class="directive"><a href="#sslproxycarevocationfile">SSLProxyCARevocationFile</a></code>
or <code class="directive"><a href="#sslproxycarevocationpath">SSLProxyCARevocationPath</a></code> must be
configured. When set to <code>chain</code> (recommended setting),
CRL checks are applied to all certificates in the chain, while setting it to
<code>leaf</code> limits the checks to the end-entity cert.
</p>
<div class="note">
<h3>When set to <code>chain</code> or <code>leaf</code>,
CRLs <em>must</em> be available for successful validation</h3>
<p>
Prior to version 2.3.15, CRL checking in mod_ssl also succeeded when
no CRL(s) were found in any of the locations configured with
<code class="directive"><a href="#sslproxycarevocationfile">SSLProxyCARevocationFile</a></code>
or <code class="directive"><a href="#sslproxycarevocationpath">SSLProxyCARevocationPath</a></code>.
With the introduction of this directive, the behavior has been changed:
when checking is enabled, CRLs <em>must</em> be present for the validation
to succeed - otherwise it will fail with an
<code>"unable to get certificate CRL"</code> error.
</p>
</div>
<div class="example"><h3>Example</h3><p><code>
SSLProxyCARevocationCheck chain
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyCARevocationFile" id="SSLProxyCARevocationFile">SSLProxyCARevocationFile</a> <a name="sslproxycarevocationfile" id="sslproxycarevocationfile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File of concatenated PEM-encoded CA CRLs for
Remote Server Auth</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyCARevocationFile <em>file-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the <em>all-in-one</em> file where you can
assemble the Certificate Revocation Lists (CRL) of Certification
Authorities (CA) whose <em>remote servers</em> you deal with. These are used
for Remote Server Authentication.  Such a file is simply the concatenation of
the various PEM-encoded CRL files, in order of preference. This can be
used alternatively and/or additionally to <code class="directive"><a href="#sslproxycarevocationpath">SSLProxyCARevocationPath</a></code>.</p>
<div class="example"><h3>Example</h3><p><code>
SSLProxyCARevocationFile /usr/local/apache2/conf/ssl.crl/ca-bundle-remote-server.crl
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyCARevocationPath" id="SSLProxyCARevocationPath">SSLProxyCARevocationPath</a> <a name="sslproxycarevocationpath" id="sslproxycarevocationpath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory of PEM-encoded CA CRLs for
Remote Server Auth</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyCARevocationPath <em>directory-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the directory where you keep the Certificate Revocation
Lists (CRL) of Certification Authorities (CAs) whose remote servers you deal with.
These are used to revoke the remote server certificate on Remote Server Authentication.</p>
<p>
The files in this directory have to be PEM-encoded and are accessed through
hash filenames. So usually you have not only to place the CRL files there.
Additionally you have to create symbolic links named
<em>hash-value</em><code>.rN</code>. And you should always make sure this directory
contains the appropriate symbolic links.</p>
<div class="example"><h3>Example</h3><p><code>
SSLProxyCARevocationPath /usr/local/apache2/conf/ssl.crl/
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyCheckPeerCN" id="SSLProxyCheckPeerCN">SSLProxyCheckPeerCN</a> <a name="sslproxycheckpeercn" id="sslproxycheckpeercn">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Whether to check the remote server certificates CN field
</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyCheckPeerCN on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLProxyCheckPeerCN on</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets whether the remote server certificates CN field is
compared against the hostname of the request URL. If both are not equal
a 502 status code (Bad Gateway) is sent.
</p>
<div class="example"><h3>Example</h3><p><code>
SSLProxyCheckPeerCN on
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyCheckPeerExpire" id="SSLProxyCheckPeerExpire">SSLProxyCheckPeerExpire</a> <a name="sslproxycheckpeerexpire" id="sslproxycheckpeerexpire">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Whether to check if remote server certificate is expired
</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyCheckPeerExpire on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLProxyCheckPeerExpire on</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets whether it is checked if the remote server certificate
is expired or not. If the check fails a 502 status code (Bad Gateway) is
sent.
</p>
<div class="example"><h3>Example</h3><p><code>
SSLProxyCheckPeerExpire on
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyCipherSuite" id="SSLProxyCipherSuite">SSLProxyCipherSuite</a> <a name="sslproxyciphersuite" id="sslproxyciphersuite">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Cipher Suite available for negotiation in SSL
proxy handshake</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyCipherSuite <em>cipher-spec</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLProxyCipherSuite ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:+LOW:+SSLv2:+EXP</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>Equivalent to <code>SSLCipherSuite</code>, but for the proxy connection.
Please refer to <code class="directive"><a href="#sslciphersuite">SSLCipherSuite</a></code>
for additional information.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyEngine" id="SSLProxyEngine">SSLProxyEngine</a> <a name="sslproxyengine" id="sslproxyengine">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>SSL Proxy Engine Operation Switch</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyEngine on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLProxyEngine off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive toggles the usage of the SSL/TLS Protocol Engine for proxy. This
is usually used inside a <code class="directive"><a href="../mod/core.html#virtualhost">&lt;VirtualHost&gt;</a></code> section to enable SSL/TLS for proxy
usage in a particular virtual host. By default the SSL/TLS Protocol Engine is
disabled for proxy image both for the main server and all configured virtual hosts.</p>
<div class="example"><h3>Example</h3><p><code>
&lt;VirtualHost _default_:443&gt;<br />
SSLProxyEngine on<br />
...<br />
&lt;/VirtualHost&gt;
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyMachineCertificateChainFile" id="SSLProxyMachineCertificateChainFile">SSLProxyMachineCertificateChainFile</a> <a name="sslproxymachinecertificatechainfile" id="sslproxymachinecertificatechainfile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File of concatenated PEM-encoded CA certificates to be used by the proxy for choosing a certificate</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyMachineCertificateChainFile <em>filename</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Not applicable</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the all-in-one file where you keep the certificate chain
for all of the client certs in use. This directive will be needed if the
remote server presents a list of CA certificates that are not direct signers
of one of the configured client certificates.
</p>
<p>
This referenced file is simply the concatenation of the various PEM-encoded
certificate files. Upon startup, each client certificate configured will
be examined and a chain of trust will be constructed.
</p>
<div class="warning"><h3>Security warning</h3>
<p>If this directive is enabled, all of the certificates in the file will be
trusted as if they were also in <code class="directive"><a href="#&#10;sslproxycacertificatefile">
SSLProxyCACertificateFile</a></code>.</p>
</div>
<div class="example"><h3>Example</h3><p><code>
SSLProxyMachineCertificateChainFile /usr/local/apache2/conf/ssl.crt/proxyCA.pem
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyMachineCertificateFile" id="SSLProxyMachineCertificateFile">SSLProxyMachineCertificateFile</a> <a name="sslproxymachinecertificatefile" id="sslproxymachinecertificatefile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>File of concatenated PEM-encoded client certificates and keys to be used by the proxy</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyMachineCertificateFile <em>filename</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Not applicable</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the all-in-one file where you keep the certificates and
keys used for authentication of the proxy server to remote servers.
</p>
<p>
This referenced file is simply the concatenation of the various PEM-encoded
certificate files, in order of preference. Use this directive alternatively
or additionally to <code>SSLProxyMachineCertificatePath</code>.
</p>
<div class="warning">
<p>Currently there is no support for encrypted private keys</p>
</div>
<div class="example"><h3>Example</h3><p><code>
SSLProxyMachineCertificateFile /usr/local/apache2/conf/ssl.crt/proxy.pem
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyMachineCertificatePath" id="SSLProxyMachineCertificatePath">SSLProxyMachineCertificatePath</a> <a name="sslproxymachinecertificatepath" id="sslproxymachinecertificatepath">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Directory of PEM-encoded client certificates and keys to be used by the proxy</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyMachineCertificatePath <em>directory</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Not applicable</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the directory where you keep the certificates and
keys used for authentication of the proxy server to remote servers.
</p>
<p>The files in this directory must be PEM-encoded and are accessed through
hash filenames. Additionally, you must create symbolic links named
<code><em>hash-value</em>.N</code>. And you should always make sure this
directory contains the appropriate symbolic links.</p>
<div class="warning">
<p>Currently there is no support for encrypted private keys</p>
</div>
<div class="example"><h3>Example</h3><p><code>
SSLProxyMachineCertificatePath /usr/local/apache2/conf/proxy.crt/
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyProtocol" id="SSLProxyProtocol">SSLProxyProtocol</a> <a name="sslproxyprotocol" id="sslproxyprotocol">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configure usable SSL protocol flavors for proxy usage</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyProtocol [+|-]<em>protocol</em> ...</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLProxyProtocol all</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Options</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>

<p>
This directive can be used to control the SSL protocol flavors mod_ssl should
use when establishing its server environment for proxy . It will only connect
to servers using one of the provided protocols.</p>
<p>Please refer to <code class="directive"><a href="#sslprotocol">SSLProtocol</a></code>
for additional information.
</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyVerify" id="SSLProxyVerify">SSLProxyVerify</a> <a name="sslproxyverify" id="sslproxyverify">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Type of remote server Certificate verification</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyVerify <em>level</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLProxyVerify none</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>

<p>When a proxy is configured to forward requests to a remote SSL
server, this directive can be used to configure certificate
verification of the remote server. </p>
<p>
The following levels are available for <em>level</em>:</p>
<ul>
<li><strong>none</strong>:
     no remote server Certificate is required at all</li>
<li><strong>optional</strong>:
     the remote server <em>may</em> present a valid Certificate</li>
<li><strong>require</strong>:
     the remote server <em>has to</em> present a valid Certificate</li>
<li><strong>optional_no_ca</strong>:
     the remote server may present a valid Certificate<br />
     but it need not to be (successfully) verifiable.</li>
</ul>
<p>In practice only levels <strong>none</strong> and
<strong>require</strong> are really interesting, because level
<strong>optional</strong> doesn't work with all servers and level
<strong>optional_no_ca</strong> is actually against the idea of
authentication (but can be used to establish SSL test pages, etc.)</p>
<div class="example"><h3>Example</h3><p><code>
SSLProxyVerify require
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLProxyVerifyDepth" id="SSLProxyVerifyDepth">SSLProxyVerifyDepth</a> <a name="sslproxyverifydepth" id="sslproxyverifydepth">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum depth of CA Certificates in Remote Server
Certificate verification</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLProxyVerifyDepth <em>number</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLProxyVerifyDepth 1</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets how deeply mod_ssl should verify before deciding that the
remote server does not have a valid certificate. </p>
<p>
The depth actually is the maximum number of intermediate certificate issuers,
i.e. the number of CA certificates which are max allowed to be followed while
verifying the remote server certificate. A depth of 0 means that self-signed
remote server certificates are accepted only, the default depth of 1 means
the remote server certificate can be self-signed or has to be signed by a CA
which is directly known to the server (i.e. the CA's certificate is under
<code class="directive"><a href="#sslproxycacertificatepath">SSLProxyCACertificatePath</a></code>), etc.</p>
<div class="example"><h3>Example</h3><p><code>
SSLProxyVerifyDepth 10
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLRandomSeed" id="SSLRandomSeed">SSLRandomSeed</a> <a name="sslrandomseed" id="sslrandomseed">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Pseudo Random Number Generator (PRNG) seeding
source</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLRandomSeed <em>context</em> <em>source</em>
[<em>bytes</em>]</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This configures one or more sources for seeding the Pseudo Random Number
Generator (PRNG) in OpenSSL at startup time (<em>context</em> is
<code>startup</code>) and/or just before a new SSL connection is established
(<em>context</em> is <code>connect</code>). This directive can only be used
in the global server context because the PRNG is a global facility.</p>
<p>
The following <em>source</em> variants are available:</p>
<ul>
<li><code>builtin</code>
    <p> This is the always available builtin seeding source. It's usage
    consumes minimum CPU cycles under runtime and hence can be always used
    without drawbacks. The source used for seeding the PRNG contains of the
    current time, the current process id and (when applicable) a randomly
    chosen 1KB extract of the inter-process scoreboard structure of Apache.
    The drawback is that this is not really a strong source and at startup
    time (where the scoreboard is still not available) this source just
    produces a few bytes of entropy. So you should always, at least for the
    startup, use an additional seeding source.</p></li>
<li><code>file:/path/to/source</code>
    <p>
    This variant uses an external file <code>/path/to/source</code> as the
    source for seeding the PRNG. When <em>bytes</em> is specified, only the
    first <em>bytes</em> number of bytes of the file form the entropy (and
    <em>bytes</em> is given to <code>/path/to/source</code> as the first
    argument). When <em>bytes</em> is not specified the whole file forms the
    entropy (and <code>0</code> is given to <code>/path/to/source</code> as
    the first argument). Use this especially at startup time, for instance
    with an available <code>/dev/random</code> and/or
    <code>/dev/urandom</code> devices (which usually exist on modern Unix
    derivatives like FreeBSD and Linux).</p>
    <p>
    <em>But be careful</em>: Usually <code>/dev/random</code> provides only as
    much entropy data as it actually has, i.e. when you request 512 bytes of
    entropy, but the device currently has only 100 bytes available two things
    can happen: On some platforms you receive only the 100 bytes while on
    other platforms the read blocks until enough bytes are available (which
    can take a long time). Here using an existing <code>/dev/urandom</code> is
    better, because it never blocks and actually gives the amount of requested
    data. The drawback is just that the quality of the received data may not
    be the best.</p>
    <p>
    On some platforms like FreeBSD one can even control how the entropy is
    actually generated, i.e. by which system interrupts. More details one can
    find under <em>rndcontrol(8)</em> on those platforms. Alternatively, when
    your system lacks such a random device, you can use tool
    like <a href="http://www.lothar.com/tech/crypto/">EGD</a>
    (Entropy Gathering Daemon) and run it's client program with the
    <code>exec:/path/to/program/</code> variant (see below) or use
    <code>egd:/path/to/egd-socket</code> (see below).</p></li>

<li><code>exec:/path/to/program</code>
    <p>
    This variant uses an external executable
    <code>/path/to/program</code> as the source for seeding the
    PRNG. When <em>bytes</em> is specified, only the first
    <em>bytes</em> number of bytes of its <code>stdout</code> contents
    form the entropy. When <em>bytes</em> is not specified, the
    entirety of the data produced on <code>stdout</code> form the
    entropy. Use this only at startup time when you need a very strong
    seeding with the help of an external program (for instance as in
    the example above with the <code>truerand</code> utility you can
    find in the mod_ssl distribution which is based on the AT&amp;T
    <em>truerand</em> library). Using this in the connection context
    slows down the server too dramatically, of course.  So usually you
    should avoid using external programs in that context.</p></li>
<li><code>egd:/path/to/egd-socket</code> (Unix only)
    <p>
    This variant uses the Unix domain socket of the
    external Entropy Gathering Daemon (EGD) (see <a href="http://www.lothar.com/tech/crypto/">http://www.lothar.com/tech
    /crypto/</a>) to seed the PRNG. Use this if no random device exists
    on your platform.</p></li>
</ul>
<div class="example"><h3>Example</h3><p><code>
SSLRandomSeed startup builtin<br />
SSLRandomSeed startup file:/dev/random<br />
SSLRandomSeed startup file:/dev/urandom 1024<br />
SSLRandomSeed startup exec:/usr/local/bin/truerand 16<br />
SSLRandomSeed connect builtin<br />
SSLRandomSeed connect file:/dev/random<br />
SSLRandomSeed connect file:/dev/urandom 1024<br />
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLRenegBufferSize" id="SSLRenegBufferSize">SSLRenegBufferSize</a> <a name="sslrenegbuffersize" id="sslrenegbuffersize">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Set the size for the SSL renegotiation buffer</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLRenegBufferSize <var>bytes</var></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLRenegBufferSize 131072</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>

<p>If an SSL renegotiation is required in per-location context, for
example, any use of <code class="directive"><a href="#sslverifyclient">SSLVerifyClient</a></code> in a Directory or
Location block, then <code class="module"><a href="../mod/mod_ssl.html">mod_ssl</a></code> must buffer any HTTP
request body into memory until the new SSL handshake can be performed.
This directive can be used to set the amount of memory that will be
used for this buffer. </p>

<div class="warning"><p>
Note that in many configurations, the client sending the request body
will be untrusted so a denial of service attack by consumption of
memory must be considered when changing this configuration setting.
</p></div>

<div class="example"><h3>Example</h3><p><code>
SSLRenegBufferSize 262144
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLRequire" id="SSLRequire">SSLRequire</a> <a name="sslrequire" id="sslrequire">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Allow access only when an arbitrarily complex
boolean expression is true</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLRequire <em>expression</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive specifies a general access requirement which has to be
fulfilled in order to allow access. It is a very powerful directive because the
requirement specification is an arbitrarily complex boolean expression
containing any number of access checks.</p>
<p>
The <em>expression</em> must match the following syntax (given as a BNF
grammar notation):</p>
<blockquote>
<pre>
expr     ::= "<strong>true</strong>" | "<strong>false</strong>"
           | "<strong>!</strong>" expr
           | expr "<strong>&amp;&amp;</strong>" expr
           | expr "<strong>||</strong>" expr
           | "<strong>(</strong>" expr "<strong>)</strong>"
           | comp

comp     ::= word "<strong>==</strong>" word | word "<strong>eq</strong>" word
           | word "<strong>!=</strong>" word | word "<strong>ne</strong>" word
           | word "<strong>&lt;</strong>"  word | word "<strong>lt</strong>" word
           | word "<strong>&lt;=</strong>" word | word "<strong>le</strong>" word
           | word "<strong>&gt;</strong>"  word | word "<strong>gt</strong>" word
           | word "<strong>&gt;=</strong>" word | word "<strong>ge</strong>" word
           | word "<strong>in</strong>" "<strong>{</strong>" wordlist "<strong>}</strong>"
           | word "<strong>in</strong>" "<strong>PeerExtList(</strong>" word "<strong>)</strong>"
           | word "<strong>=~</strong>" regex
           | word "<strong>!~</strong>" regex

wordlist ::= word
           | wordlist "<strong>,</strong>" word

word     ::= digit
           | cstring
           | variable
           | function

digit    ::= [0-9]+
cstring  ::= "..."
variable ::= "<strong>%{</strong>" varname "<strong>}</strong>"
function ::= funcname "<strong>(</strong>" funcargs "<strong>)</strong>"
</pre>
</blockquote>
<p>For <code>varname</code> any of the variables described in <a href="#envvars">Environment Variables</a> can be used.  For
<code>funcname</code> the available functions are listed in
the <a href="../expr.html#functions">ap_expr documentation</a>.</p>

<p>Notice that <em>expression</em> is first parsed into an internal machine
representation and then evaluated in a second step. Actually, in Global and
Per-Server Class context <em>expression</em> is parsed at startup time and
at runtime only the machine representation is executed. For Per-Directory
context this is different: here <em>expression</em> has to be parsed and
immediately executed for every request.</p>
<div class="example"><h3>Example</h3><pre>SSLRequire (    %{SSL_CIPHER} !~ m/^(EXP|NULL)-/                \
            and %{SSL_CLIENT_S_DN_O} eq "Snake Oil, Ltd."        \
            and %{SSL_CLIENT_S_DN_OU} in {"Staff", "CA", "Dev"}  \
            and %{TIME_WDAY} &gt;= 1 and %{TIME_WDAY} &lt;= 5          \
            and %{TIME_HOUR} &gt;= 8 and %{TIME_HOUR} &lt;= 20       ) \
           or %{REMOTE_ADDR} =~ m/^192\.76\.162\.[0-9]+$/</pre></div>

<p>The <code>PeerExtList(<em>object-ID</em>)</code> function expects
to find zero or more instances of the X.509 certificate extension
identified by the given <em>object ID</em> (OID) in the client certificate.
The expression evaluates to true if the left-hand side string matches
exactly against the value of an extension identified with this OID.
(If multiple extensions with the same OID are present, at least one
extension must match).</p>

<div class="example"><h3>Example</h3><p><code>
SSLRequire "foobar" in PeerExtList("1.2.3.4.5.6")
</code></p></div>

<div class="note"><h3>Notes on the PeerExtList function</h3>

<ul>

<li><p>The object ID can be specified either as a descriptive
name recognized by the SSL library, such as <code>"nsComment"</code>,
or as a numeric OID, such as <code>"1.2.3.4.5.6"</code>.</p></li>

<li><p>Expressions with types known to the SSL library are rendered to
a string before comparison.  For an extension with a type not
recognized by the SSL library, mod_ssl will parse the value if it is
one of the primitive ASN.1 types UTF8String, IA5String, VisibleString,
or BMPString.  For an extension of one of these types, the string
value will be converted to UTF-8 if necessary, then compared against
the left-hand-side expression.</p></li>

</ul>
</div>

<div class="note"><h3>SSLRequire is deprecated</h3>
<p><code>SSLRequire</code> is deprecated and should in general be replaced
by <a href="mod_authz_core.html#reqexpr">Require expr</a>. The so called
<a href="../expr.html">ap_expr</a> syntax of <code>Require expr</code> is
a superset of the syntax of <code>SSLRequire</code>, with the following
exception:</p>

<p>In <code>SSLRequire</code>, the comparison operators <code>&lt;</code>,
<code>&lt;=</code>, ... are completely equivalent to the operators
<code>lt</code>, <code>le</code>, ... and work in a somewhat pecular way that
first compares the length of two strings and then the lexical order.
On the other hand, <a href="../expr.html">ap_expr</a> has two sets of
comparison operators: The operators <code>&lt;</code>,
<code>&lt;=</code>, ... do lexical string comparison, while the operators
<code>-lt</code>, <code>-le</code>, ... do integer comparison.
For the latter, there are also aliases without the leading dashes:
<code>lt</code>, <code>le</code>, ...
</p>

</div>


<h3>See also</h3>
<ul>
<li><a href="../env.html">Environment Variables in Apache HTTP Server</a>,
for additional examples.
</li>
<li><a href="mod_authz_core.html#reqexpr">Require expr</a></li>
<li><a href="../expr.html">Generic expression syntax in Apache HTTP Server</a>
</li>
</ul>
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLRequireSSL" id="SSLRequireSSL">SSLRequireSSL</a> <a name="sslrequiressl" id="sslrequiressl">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Deny access when SSL is not used for the
HTTP request</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLRequireSSL</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive forbids access unless HTTP over SSL (i.e. HTTPS) is enabled for
the current connection. This is very handy inside the SSL-enabled virtual
host or directories for defending against configuration errors that expose
stuff that should be protected. When this directive is present all requests
are denied which are not using SSL.</p>
<div class="example"><h3>Example</h3><p><code>
SSLRequireSSL
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLSessionCache" id="SSLSessionCache">SSLSessionCache</a> <a name="sslsessioncache" id="sslsessioncache">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Type of the global/inter-process SSL Session
Cache</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLSessionCache <em>type</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLSessionCache none</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This configures the storage type of the global/inter-process SSL Session
Cache. This cache is an optional facility which speeds up parallel request
processing. For requests to the same server process (via HTTP keep-alive),
OpenSSL already caches the SSL session information locally. But because modern
clients request inlined images and other data via parallel requests (usually
up to four parallel requests are common) those requests are served by
<em>different</em> pre-forked server processes. Here an inter-process cache
helps to avoid unnecessary session handshakes.</p>
<p>
The following five storage <em>type</em>s are currently supported:</p>
<ul>
<li><code>none</code>

    <p>This disables the global/inter-process Session Cache.  This
    will incur a noticeable speed penalty and may cause problems if
    using certain browsers, particularly if client certificates are
    enabled.  This setting is not recommended.</p></li>

<li><code>nonenotnull</code>

    <p>This disables any global/inter-process Session Cache.  However
    it does force OpenSSL to send a non-null session ID to
    accommodate buggy clients that require one.</p></li>

<li><code>dbm:/path/to/datafile</code>

    <p>This makes use of a DBM hashfile on the local disk to
    synchronize the local OpenSSL memory caches of the server
    processes. This session cache may suffer reliability issues under
    high load. To use this, ensure that
    <code class="module"><a href="../mod/mod_socache_dbm.html">mod_socache_dbm</a></code> is loaded.</p></li>

<li><code>shmcb:/path/to/datafile</code>[<code>(</code><em>size</em><code>)</code>]

    <p>This makes use of a high-performance cyclic buffer
    (approx. <em>size</em> bytes in size) inside a shared memory
    segment in RAM (established via <code>/path/to/datafile</code>) to
    synchronize the local OpenSSL memory caches of the server
    processes.  This is the recommended session cache. To use this,
    ensure that <code class="module"><a href="../mod/mod_socache_shmcb.html">mod_socache_shmcb</a></code> is loaded.</p></li>

<li><code>dc:UNIX:/path/to/socket</code>

    <p>This makes use of the <a href="http://www.distcache.org/">distcache</a> distributed session
    caching libraries.  The argument should specify the location of
    the server or proxy to be used using the distcache address syntax;
    for example, <code>UNIX:/path/to/socket</code> specifies a UNIX
    domain socket (typically a local dc_client proxy);
    <code>IP:server.example.com:9001</code> specifies an IP
    address. To use this, ensure that
    <code class="module"><a href="../mod/mod_socache_dc.html">mod_socache_dc</a></code> is loaded.</p></li>

</ul>

<div class="example"><h3>Examples</h3><p><code>
SSLSessionCache dbm:/usr/local/apache/logs/ssl_gcache_data<br />
SSLSessionCache shmcb:/usr/local/apache/logs/ssl_gcache_data(512000)
</code></p></div>

<p>The <code>ssl-cache</code> mutex is used to serialize access to
the session cache to prevent corruption.  This mutex can be configured
using the <code class="directive"><a href="../mod/core.html#mutex">Mutex</a></code> directive.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLSessionCacheTimeout" id="SSLSessionCacheTimeout">SSLSessionCacheTimeout</a> <a name="sslsessioncachetimeout" id="sslsessioncachetimeout">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of seconds before an SSL session expires
in the Session Cache</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLSessionCacheTimeout <em>seconds</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLSessionCacheTimeout 300</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the timeout in seconds for the information stored in the
global/inter-process SSL Session Cache and the OpenSSL internal memory cache.
It can be set as low as 15 for testing, but should be set to higher
values like 300 in real life.</p>
<div class="example"><h3>Example</h3><p><code>
SSLSessionCacheTimeout 600
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLSessionTicketKeyFile" id="SSLSessionTicketKeyFile">SSLSessionTicketKeyFile</a> <a name="sslsessionticketkeyfile" id="sslsessionticketkeyfile">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Persistent encryption/decryption key for TLS session tickets</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLSessionTicketKeyFile <em>file-path</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.4.0 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>Optionally configures a secret key for encrypting and decrypting
TLS session tickets, as defined in
<a href="http://www.ietf.org/rfc/rfc5077.txt">RFC 5077</a>.
Primarily suitable for clustered environments where TLS sessions information
should be shared between multiple nodes. For single-instance httpd setups,
it is recommended to <em>not</em> configure a ticket key file, but to
rely on (random) keys generated by mod_ssl at startup, instead.</p>
<p>The ticket key file must contain 48 bytes of random data,
preferrably created from a high-entropy source. On a Unix-based system,
a ticket key file can be created as follows:</p>

<div class="example"><p><code>
dd if=/dev/random of=/path/to/file.tkey bs=1 count=48
</code></p></div>

<p>Ticket keys should be rotated (replaced) on a frequent basis,
as this is the only way to invalidate an existing session ticket -
OpenSSL currently doesn't allow to specify a limit for ticket lifetimes.</p>

<div class="warning">
<p>The ticket key file contains sensitive keying material and should
be protected with file permissions similar to those used for
<code class="directive"><a href="#sslcertificatekeyfile">SSLCertificateKeyFile</a></code>.</p>
</div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStaplingCache" id="SSLStaplingCache">SSLStaplingCache</a> <a name="sslstaplingcache" id="sslstaplingcache">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Configures the OCSP stapling cache</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStaplingCache <em>type</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>Configures the cache used to store OCSP responses which get included
in the TLS handshake if <code class="directive"><a href="#sslusestapling">SSLUseStapling</a></code>
is enabled. Configuration of a cache is mandatory for OCSP stapling.
With the exception of <code>none</code> and <code>nonenotnull</code>,
the same storage types are supported as with
<code class="directive"><a href="#sslsessioncache">SSLSessionCache</a></code>.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStaplingErrorCacheTimeout" id="SSLStaplingErrorCacheTimeout">SSLStaplingErrorCacheTimeout</a> <a name="sslstaplingerrorcachetimeout" id="sslstaplingerrorcachetimeout">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of seconds before expiring invalid responses in the OCSP stapling cache</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStaplingErrorCacheTimeout <em>seconds</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLStaplingErrorCacheTimeout 600</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>Sets the timeout in seconds before <em>invalid</em> responses
in the OCSP stapling cache (configured through <code class="directive"><a href="#sslstaplingcache">SSLStaplingCache</a></code>) will expire.
To set the cache timeout for valid responses, see
<code class="directive"><a href="#sslstaplingstandardcachetimeout">SSLStaplingStandardCacheTimeout</a></code>.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStaplingFakeTryLater" id="SSLStaplingFakeTryLater">SSLStaplingFakeTryLater</a> <a name="sslstaplingfaketrylater" id="sslstaplingfaketrylater">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Synthesize "tryLater" responses for failed OCSP stapling queries</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStaplingFakeTryLater on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLStaplingFakeTryLater on</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>When enabled and a query to an OCSP responder for stapling
purposes fails, mod_ssl will synthesize a "tryLater" response for the
client. Only effective if <code class="directive"><a href="#sslstaplingreturnrespondererrors">SSLStaplingReturnResponderErrors</a></code>
is also enabled.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStaplingForceURL" id="SSLStaplingForceURL">SSLStaplingForceURL</a> <a name="sslstaplingforceurl" id="sslstaplingforceurl">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Override the OCSP responder URI specified in the certificate's AIA extension</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStaplingForceURL <em>uri</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>This directive overrides the URI of an OCSP responder as obtained from
the authorityInfoAccess (AIA) extension of the certificate.
Of potential use when going through a proxy for retrieving OCSP queries.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStaplingResponderTimeout" id="SSLStaplingResponderTimeout">SSLStaplingResponderTimeout</a> <a name="sslstaplingrespondertimeout" id="sslstaplingrespondertimeout">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Timeout for OCSP stapling queries</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStaplingResponderTimeout <em>seconds</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLStaplingResponderTimeout 10</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>This option sets the timeout for queries to OCSP responders when
<code class="directive"><a href="#sslusestapling">SSLUseStapling</a></code> is enabled
and mod_ssl is querying a responder for OCSP stapling purposes.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStaplingResponseMaxAge" id="SSLStaplingResponseMaxAge">SSLStaplingResponseMaxAge</a> <a name="sslstaplingresponsemaxage" id="sslstaplingresponsemaxage">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum allowable age for OCSP stapling responses</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStaplingResponseMaxAge <em>seconds</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLStaplingResponseMaxAge -1</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>This option sets the maximum allowable age ("freshness") when
considering OCSP responses for stapling purposes, i.e. when
<code class="directive"><a href="#sslusestapling">SSLUseStapling</a></code> is turned on.
The default value (<code>-1</code>) does not enforce a maximum age,
which means that OCSP responses are considered valid as long as their
<code>nextUpdate</code> field is in the future.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStaplingResponseTimeSkew" id="SSLStaplingResponseTimeSkew">SSLStaplingResponseTimeSkew</a> <a name="sslstaplingresponsetimeskew" id="sslstaplingresponsetimeskew">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum allowable time skew for OCSP stapling response validation</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStaplingResponseTimeSkew <em>seconds</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLStaplingResponseTimeSkew 300</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>This option sets the maximum allowable time skew when mod_ssl checks the
<code>thisUpdate</code> and <code>nextUpdate</code> fields of OCSP responses
which get included in the TLS handshake (OCSP stapling). Only applicable
if <code class="directive"><a href="#sslusestapling">SSLUseStapling</a></code> is turned on.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStaplingReturnResponderErrors" id="SSLStaplingReturnResponderErrors">SSLStaplingReturnResponderErrors</a> <a name="sslstaplingreturnrespondererrors" id="sslstaplingreturnrespondererrors">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Pass stapling related OCSP errors on to client</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStaplingReturnResponderErrors on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLStaplingReturnResponderErrors on</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>When enabled, mod_ssl will pass responses from unsuccessful
stapling related OCSP queries (such as status errors, expired responses etc.)
on to the client. If set to <code>off</code>, no stapled responses
for failed queries will be included in the TLS handshake.</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStaplingStandardCacheTimeout" id="SSLStaplingStandardCacheTimeout">SSLStaplingStandardCacheTimeout</a> <a name="sslstaplingstandardcachetimeout" id="sslstaplingstandardcachetimeout">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Number of seconds before expiring responses in the OCSP stapling cache</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStaplingStandardCacheTimeout <em>seconds</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLStaplingStandardCacheTimeout 3600</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>Sets the timeout in seconds before responses in the OCSP stapling cache
(configured through <code class="directive"><a href="#sslstaplingcache">SSLStaplingCache</a></code>)
will expire. This directive applies to <em>valid</em> responses, while
<code class="directive"><a href="#sslstaplingerrorcachetimeout">SSLStaplingErrorCacheTimeout</a></code> is
used for controlling the timeout for invalid/unavailable responses.
</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLStrictSNIVHostCheck" id="SSLStrictSNIVHostCheck">SSLStrictSNIVHostCheck</a> <a name="sslstrictsnivhostcheck" id="sslstrictsnivhostcheck">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Whether to allow non-SNI clients to access a name-based virtual
host.
</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLStrictSNIVHostCheck on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLStrictSNIVHostCheck off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.2.12 and later</td></tr>
</table>
<p>
This directive sets whether a non-SNI client is allowed to access a name-based
virtual host. If set to <code>on</code> in the default name-based virtual
host, clients that are SNI unaware will not be allowed to access <em>any</em>
virtual host, belonging to this particular IP / port combination.
If set to <code>on</code> in any other virtual host, SNI unaware clients
are not allowed to access this particular virtual host.
</p>

<div class="warning"><p>
This option is only available if httpd was compiled against an SNI capable
version of OpenSSL.
</p></div>

<div class="example"><h3>Example</h3><p><code>
SSLStrictSNIVHostCheck on
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLUserName" id="SSLUserName">SSLUserName</a> <a name="sslusername" id="sslusername">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Variable name to determine user name</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLUserName <em>varname</em></code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in Apache 2.0.51 and later</td></tr>
</table>
<p>
This directive sets the "user" field in the Apache request object.
This is used by lower modules to identify the user with a character
string. In particular, this may cause the environment variable
<code>REMOTE_USER</code> to be set.  The <em>varname</em> can be
any of the <a href="#envvars">SSL environment variables</a>.</p>

<p>Note that this directive has no effect if the
<code>FakeBasicAuth</code> option is used (see <a href="#ssloptions">SSLOptions</a>).</p>

<div class="example"><h3>Example</h3><p><code>
SSLUserName SSL_CLIENT_S_DN_CN
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLUseStapling" id="SSLUseStapling">SSLUseStapling</a> <a name="sslusestapling" id="sslusestapling">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enable stapling of OCSP responses in the TLS handshake</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLUseStapling on|off</code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLUseStapling off</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>Available in httpd 2.3.3 and later, if using OpenSSL 0.9.8h or later</td></tr>
</table>
<p>This option enables OCSP stapling, as defined by the "Certificate
Status Request" TLS extension specified in RFC 6066. If enabled (and
requested by the client), mod_ssl will include an OCSP response
for its own certificate in the TLS handshake. Configuring an
<code class="directive"><a href="#sslstaplingcache">SSLStaplingCache</a></code> is a
prerequisite for enabling OCSP stapling.</p>

<p>OCSP stapling relieves the client of querying the OCSP responder
on its own, but it should be noted that in its current specification,
the server's <code>CertificateStatus</code> reply may only include an
OCSP response for a single cert. For server certificates with intermediate
CA certificates in their chain (the typical case nowadays),
stapling in its current form therefore only partially achieves the
stated goal of "saving roundtrips and resources" - see also the <a href="https://datatracker.ietf.org/doc/draft-pettersen-tls-ext-multiple-ocsp/">
"Adding Multiple TLS Certificate Status Extension requests"</a> Internet draft.
</p>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLVerifyClient" id="SSLVerifyClient">SSLVerifyClient</a> <a name="sslverifyclient" id="sslverifyclient">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Type of Client Certificate verification</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLVerifyClient <em>level</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLVerifyClient none</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets the Certificate verification level for the Client
Authentication. Notice that this directive can be used both in per-server and
per-directory context. In per-server context it applies to the client
authentication process used in the standard SSL handshake when a connection is
established. In per-directory context it forces a SSL renegotiation with the
reconfigured client verification level after the HTTP request was read but
before the HTTP response is sent.</p>
<p>
The following levels are available for <em>level</em>:</p>
<ul>
<li><strong>none</strong>:
     no client Certificate is required at all</li>
<li><strong>optional</strong>:
     the client <em>may</em> present a valid Certificate</li>
<li><strong>require</strong>:
     the client <em>has to</em> present a valid Certificate</li>
<li><strong>optional_no_ca</strong>:
     the client may present a valid Certificate<br />
     but it need not to be (successfully) verifiable.</li>
</ul>
<p>In practice only levels <strong>none</strong> and
<strong>require</strong> are really interesting, because level
<strong>optional</strong> doesn't work with all browsers and level
<strong>optional_no_ca</strong> is actually against the idea of
authentication (but can be used to establish SSL test pages, etc.)</p>
<div class="example"><h3>Example</h3><p><code>
SSLVerifyClient require
</code></p></div>

</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="SSLVerifyDepth" id="SSLVerifyDepth">SSLVerifyDepth</a> <a name="sslverifydepth" id="sslverifydepth">Directive</a></h2>
<table class="directive">
<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Maximum depth of CA Certificates in Client
Certificate verification</td></tr>
<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>SSLVerifyDepth <em>number</em></code></td></tr>
<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>SSLVerifyDepth 1</code></td></tr>
<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr>
<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>AuthConfig</td></tr>
<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr>
<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_ssl</td></tr>
</table>
<p>
This directive sets how deeply mod_ssl should verify before deciding that the
clients don't have a valid certificate. Notice that this directive can be
used both in per-server and per-directory context. In per-server context it
applies to the client authentication process used in the standard SSL
handshake when a connection is established. In per-directory context it forces
a SSL renegotiation with the reconfigured client verification depth after the
HTTP request was read but before the HTTP response is sent.</p>
<p>
The depth actually is the maximum number of intermediate certificate issuers,
i.e. the number of CA certificates which are max allowed to be followed while
verifying the client certificate. A depth of 0 means that self-signed client
certificates are accepted only, the default depth of 1 means the client
certificate can be self-signed or has to be signed by a CA which is directly
known to the server (i.e. the CA's certificate is under
<code class="directive"><a href="#sslcacertificatepath">SSLCACertificatePath</a></code>), etc.</p>
<div class="example"><h3>Example</h3><p><code>
SSLVerifyDepth 10
</code></p></div>

</div>
</div>
<div class="bottomlang">
<p><span>Available Languages: </span><a href="../en/mod/mod_ssl.html" title="English">&nbsp;en&nbsp;</a></p>
</div><div id="footer">
<p class="apache">Copyright 2012 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p>
<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div>
</body></html>