cipher reorganisiert

16 files changed, 222 insertions, 300 deletions

diff --git a/g10/ChangeLog b/g10/ChangeLog
index e16f15550..d3e06d2b7 100644
--- a/g10/ChangeLog
+++ b/g10/ChangeLog
@@ -1,3 +1,18 @@
+Tue Apr  7 19:28:07 1998  Werner Koch  (wk@isil.d.shuttle.de)
+
+	* cipher.c, encr-data.c, seckey-cert.c: Now uses cipher_xxxx
+	functions instead of blowfish_xxx or cast_xxx
+
+Tue Apr  7 11:04:02 1998  Werner Koch  (wk@isil.d.shuttle.de)
+
+	* Makefile.am (g10maint.o): Changed the way it is created.
+
+Mon Apr  6 11:17:08 1998  Werner Koch  (wk@isil.d.shuttle.de)
+
+	* misc.c: New.
+	* keygen.c (checksum,checksum_u16,checksum_mpi): Moved to misc.c
+	* seckey-cert.c: Kludge for wrong ELG checksum implementation.
+
 Sat Apr  4 20:07:01 1998  Werner Koch  (wk@isil.d.shuttle.de)
 
 	* cipher.c (cipher_filter): Support for CAST5
diff --git a/g10/Makefile.am b/g10/Makefile.am
index 438acec19..ba9ca29df 100644
--- a/g10/Makefile.am
+++ b/g10/Makefile.am
@@ -3,7 +3,6 @@
 INCLUDES = -I$(top_srcdir)/include -I$(top_srcdir)/intl -I../intl
 EXTRA_DIST = OPTIONS  pubring.asc
 OMIT_DEPENDENCIES = zlib.h zconf.h
-BUILT_SOURCES = g10maint.c
 needed_libs = ../cipher/libcipher.a ../mpi/libmpi.a ../util/libutil.a
 
 bin_PROGRAMS = gpg gpgm gpgd
@@ -28,6 +27,7 @@ common_source =  \
 	      elg.c		\
 	      dsa.c		\
 	      rsa.c		\
+	      misc.c		\
 	      options.h 	\
 	      openfile.c	\
 	      keyid.c		\
@@ -60,8 +60,7 @@ gpg_SOURCES  = g10.c		\
 	      keygen.c
 
 
-gpgm_SOURCES = g10maint.c   \
-	      dearmor.c     \
+gpgm_SOURCES = dearmor.c     \
 	      $(common_source)
 
 gpgd_SOURCES = gpgd.c \
@@ -70,8 +69,11 @@ gpgd_SOURCES = gpgd.c \
 
 LDADD = @INTLLIBS@ $(needed_libs) @ZLIBS@
 
-g10maint.c : g10.c
-	    $(CPP) $(CFLAGS) $(DEFS) $(INCLUDES) -DIS_G10MAINT $< > $@ || rm $@
+gpgm_LDADD = g10maint.o $(LDADD)
+
+g10maint.o: g10.c
+	$(COMPILE) -DIS_G10MAINT  -o g10maint.o -c g10.c
+
 
 $(PROGRAMS): $(needed_libs)
 
diff --git a/g10/Makefile.in b/g10/Makefile.in
index 60aed6e28..b2a106c2b 100644
--- a/g10/Makefile.in
+++ b/g10/Makefile.in
@@ -95,7 +95,6 @@ l = @l@
 INCLUDES = -I$(top_srcdir)/include -I$(top_srcdir)/intl -I../intl
 EXTRA_DIST = OPTIONS  pubring.asc
 OMIT_DEPENDENCIES = zlib.h zconf.h
-BUILT_SOURCES = g10maint.c
 needed_libs = ../cipher/libcipher.a ../mpi/libmpi.a ../util/libutil.a
 
 bin_PROGRAMS = gpg gpgm gpgd
@@ -120,6 +119,7 @@ common_source =  \
 	      elg.c		\
 	      dsa.c		\
 	      rsa.c		\
+	      misc.c		\
 	      options.h 	\
 	      openfile.c	\
 	      keyid.c		\
@@ -151,14 +151,15 @@ gpg_SOURCES  = g10.c		\
 	      decrypt.c 	\
 	      keygen.c
 
-gpgm_SOURCES = g10maint.c   \
-	      dearmor.c     \
+gpgm_SOURCES = dearmor.c     \
 	      $(common_source)
 
 gpgd_SOURCES = gpgd.c \
 	      $(common_source)
 
 LDADD = @INTLLIBS@ $(needed_libs) @ZLIBS@
+
+gpgm_LDADD = g10maint.o $(LDADD)
 mkinstalldirs = $(SHELL) $(top_srcdir)/scripts/mkinstalldirs
 CONFIG_HEADER = ../config.h
 CONFIG_CLEAN_FILES = 
@@ -171,32 +172,31 @@ LDFLAGS = @LDFLAGS@
 LIBS = @LIBS@
 gpg_OBJECTS =  g10.o build-packet.o compress.o free-packet.o getkey.o \
 pkclist.o skclist.o ringedit.o kbnode.o mainproc.o armor.o mdfilter.o \
-textfilter.o cipher.o elg.o dsa.o rsa.o openfile.o keyid.o trustdb.o \
-parse-packet.o passphrase.o pubkey-enc.o seckey-cert.o seskey.o \
-import.o export.o comment.o status.o sign.o plaintext.o encr-data.o \
-encode.o revoke.o keylist.o sig-check.o signal.o verify.o decrypt.o \
-keygen.o
+textfilter.o cipher.o elg.o dsa.o rsa.o misc.o openfile.o keyid.o \
+trustdb.o parse-packet.o passphrase.o pubkey-enc.o seckey-cert.o \
+seskey.o import.o export.o comment.o status.o sign.o plaintext.o \
+encr-data.o encode.o revoke.o keylist.o sig-check.o signal.o verify.o \
+decrypt.o keygen.o
 gpg_LDADD = $(LDADD)
 gpg_DEPENDENCIES =  ../cipher/libcipher.a ../mpi/libmpi.a \
 ../util/libutil.a
 gpg_LDFLAGS = 
-gpgm_OBJECTS =  g10maint.o dearmor.o build-packet.o compress.o \
-free-packet.o getkey.o pkclist.o skclist.o ringedit.o kbnode.o \
-mainproc.o armor.o mdfilter.o textfilter.o cipher.o elg.o dsa.o rsa.o \
-openfile.o keyid.o trustdb.o parse-packet.o passphrase.o pubkey-enc.o \
+gpgm_OBJECTS =  dearmor.o build-packet.o compress.o free-packet.o \
+getkey.o pkclist.o skclist.o ringedit.o kbnode.o mainproc.o armor.o \
+mdfilter.o textfilter.o cipher.o elg.o dsa.o rsa.o misc.o openfile.o \
+keyid.o trustdb.o parse-packet.o passphrase.o pubkey-enc.o \
 seckey-cert.o seskey.o import.o export.o comment.o status.o sign.o \
 plaintext.o encr-data.o encode.o revoke.o keylist.o sig-check.o \
 signal.o
-gpgm_LDADD = $(LDADD)
-gpgm_DEPENDENCIES =  ../cipher/libcipher.a ../mpi/libmpi.a \
+gpgm_DEPENDENCIES =  g10maint.o ../cipher/libcipher.a ../mpi/libmpi.a \
 ../util/libutil.a
 gpgm_LDFLAGS = 
 gpgd_OBJECTS =  gpgd.o build-packet.o compress.o free-packet.o getkey.o \
 pkclist.o skclist.o ringedit.o kbnode.o mainproc.o armor.o mdfilter.o \
-textfilter.o cipher.o elg.o dsa.o rsa.o openfile.o keyid.o trustdb.o \
-parse-packet.o passphrase.o pubkey-enc.o seckey-cert.o seskey.o \
-import.o export.o comment.o status.o sign.o plaintext.o encr-data.o \
-encode.o revoke.o keylist.o sig-check.o signal.o
+textfilter.o cipher.o elg.o dsa.o rsa.o misc.o openfile.o keyid.o \
+trustdb.o parse-packet.o passphrase.o pubkey-enc.o seckey-cert.o \
+seskey.o import.o export.o comment.o status.o sign.o plaintext.o \
+encr-data.o encode.o revoke.o keylist.o sig-check.o signal.o
 gpgd_LDADD = $(LDADD)
 gpgd_DEPENDENCIES =  ../cipher/libcipher.a ../mpi/libmpi.a \
 ../util/libutil.a
@@ -214,15 +214,14 @@ GZIP = --best
 DEP_FILES =  .deps/armor.P .deps/build-packet.P .deps/cipher.P \
 .deps/comment.P .deps/compress.P .deps/dearmor.P .deps/decrypt.P \
 .deps/dsa.P .deps/elg.P .deps/encode.P .deps/encr-data.P .deps/export.P \
-.deps/free-packet.P .deps/g10.P .deps/g10maint .deps/g10maint.P \
-.deps/getkey.P .deps/gpgd.P .deps/import.P .deps/kbnode.P \
-.deps/keygen.P .deps/keyid.P .deps/keylist.P .deps/mainproc.P \
-.deps/mdfilter.P .deps/openfile.P .deps/parse-packet.P \
-.deps/passphrase.P .deps/pkclist.P .deps/plaintext.P .deps/pubkey-enc.P \
-.deps/revoke.P .deps/ringedit.P .deps/rsa.P .deps/seckey-cert.P \
-.deps/seskey.P .deps/sig-check.P .deps/sign.P .deps/signal.P \
-.deps/skclist.P .deps/status.P .deps/textfilter.P .deps/trustdb.P \
-.deps/verify.P
+.deps/free-packet.P .deps/g10.P .deps/getkey.P .deps/gpgd.P \
+.deps/import.P .deps/kbnode.P .deps/keygen.P .deps/keyid.P \
+.deps/keylist.P .deps/mainproc.P .deps/mdfilter.P .deps/misc.P \
+.deps/openfile.P .deps/parse-packet.P .deps/passphrase.P \
+.deps/pkclist.P .deps/plaintext.P .deps/pubkey-enc.P .deps/revoke.P \
+.deps/ringedit.P .deps/rsa.P .deps/seckey-cert.P .deps/seskey.P \
+.deps/sig-check.P .deps/sign.P .deps/signal.P .deps/skclist.P \
+.deps/status.P .deps/textfilter.P .deps/trustdb.P .deps/verify.P
 SOURCES = $(gpg_SOURCES) $(gpgm_SOURCES) $(gpgd_SOURCES)
 OBJECTS = $(gpg_OBJECTS) $(gpgm_OBJECTS) $(gpgd_OBJECTS)
 
@@ -421,8 +420,8 @@ installdirs mostlyclean-generic distclean-generic clean-generic \
 maintainer-clean-generic clean mostlyclean distclean maintainer-clean
 
 
-g10maint.c : g10.c
-	    $(CPP) $(CFLAGS) $(DEFS) $(INCLUDES) -DIS_G10MAINT $< > $@ || rm $@
+g10maint.o: g10.c
+	$(COMPILE) -DIS_G10MAINT  -o g10maint.o -c g10.c
 
 $(PROGRAMS): $(needed_libs)
 
diff --git a/g10/cipher.c b/g10/cipher.c
index 8e6c91aa9..3fe4e9ea4 100644
--- a/g10/cipher.c
+++ b/g10/cipher.c
@@ -67,42 +67,21 @@ cipher_filter( void *opaque, int control,
 	    randomize_buffer( temp, 8, 1 );
 	    temp[8] = temp[6];
 	    temp[9] = temp[7];
-	    if( cfx->dek->algo == CIPHER_ALGO_BLOWFISH
-	       || cfx->dek->algo == CIPHER_ALGO_BLOWFISH128 ) {
-		cfx->bf_ctx = m_alloc_secure( sizeof *cfx->bf_ctx );
-		blowfish_setkey( cfx->bf_ctx, cfx->dek->key, cfx->dek->keylen );
-		blowfish_setiv( cfx->bf_ctx, NULL );
-		blowfish_encode_cfb( cfx->bf_ctx, temp, temp, 10);
-	    }
-	    else if( cfx->dek->algo == CIPHER_ALGO_CAST  ) {
-		cfx->cast5_ctx = m_alloc_secure( sizeof *cfx->cast5_ctx );
-		cast5_setkey( cfx->cast5_ctx, cfx->dek->key, cfx->dek->keylen );
-		cast5_setiv( cfx->cast5_ctx, NULL );
-		cast5_encode_cfb( cfx->cast5_ctx, temp, temp, 10);
-		cast5_sync_cfb( cfx->cast5_ctx );
-	    }
-	    else
-		log_bug("no cipher algo %d\n", cfx->dek->algo);
-
+	    cfx->cipher_hd = cipher_open( cfx->dek->algo,
+					  CIPHER_MODE_AUTO_CFB, 1 );
+	    cipher_setkey( cfx->cipher_hd, cfx->dek->key, cfx->dek->keylen );
+	    cipher_setiv( cfx->cipher_hd, NULL );
+	    cipher_encrypt( cfx->cipher_hd, temp, temp, 10);
+	    cipher_sync( cfx->cipher_hd );
 	    iobuf_write(a, temp, 10);
 	    cfx->header=1;
 	}
-
-	if( cfx->dek->algo == CIPHER_ALGO_BLOWFISH
-	    || cfx->dek->algo == CIPHER_ALGO_BLOWFISH128 )
-	    blowfish_encode_cfb( cfx->bf_ctx, buf, buf, size);
-	else if( cfx->dek->algo == CIPHER_ALGO_CAST  )
-	    cast5_encode_cfb( cfx->cast5_ctx, buf, buf, size);
-
+	cipher_encrypt( cfx->cipher_hd, buf, buf, size);
 	if( iobuf_write( a, buf, size ) )
 	    rc = G10ERR_WRITE_FILE;
     }
     else if( control == IOBUFCTRL_FREE ) {
-	if( cfx->dek->algo == CIPHER_ALGO_BLOWFISH
-	    || cfx->dek->algo == CIPHER_ALGO_BLOWFISH128 )
-	    m_free(cfx->bf_ctx);
-	else if( cfx->dek->algo == CIPHER_ALGO_CAST  )
-	    m_free(cfx->cast5_ctx);
+	cipher_close(cfx->cipher_hd);
     }
     else if( control == IOBUFCTRL_DESC ) {
 	*(char**)buf = "cipher_filter";
diff --git a/g10/comment.c b/g10/comment.c
index 77b9a7ece..fef831cc7 100644
--- a/g10/comment.c
+++ b/g10/comment.c
@@ -79,9 +79,6 @@ make_mpi_comment_node( const char *s, MPI a )
 
     nb1 = mpi_get_nbits( a );
     p = buf = mpi_get_buffer( a, &n1, NULL );
-    for( ; !*p && n1; p++, n1-- )  /* skip leading null bytes */
-	;
-
     pkt = m_alloc_clear( sizeof *pkt );
     pkt->pkttype = PKT_COMMENT;
     pkt->pkt.comment = m_alloc( sizeof *pkt->pkt.comment + n + 2 + n1 );
diff --git a/g10/encr-data.c b/g10/encr-data.c
index 4f8aa897d..e7e56408a 100644
--- a/g10/encr-data.c
+++ b/g10/encr-data.c
@@ -35,9 +35,7 @@ static int decode_filter( void *opaque, int control, IOBUF a,
 					byte *buf, size_t *ret_len);
 
 typedef struct {
-    int is_cast5;
-    BLOWFISH_context *bf_ctx;
-    CAST5_context *cast5_ctx;
+    CIPHER_HANDLE cipher_hd;
 } decode_filter_ctx_t;
 
 
@@ -50,7 +48,7 @@ decrypt_data( PKT_encrypted *ed, DEK *dek )
 {
     decode_filter_ctx_t dfx;
     byte *p;
-    int c, i;
+    int rc, c, i;
     byte temp[16];
 
     if( opt.verbose ) {
@@ -60,25 +58,14 @@ decrypt_data( PKT_encrypted *ed, DEK *dek )
 	else
 	    log_info("encrypted with unknown algorithm %d\n", dek->algo );
     }
-    if( dek->algo != CIPHER_ALGO_BLOWFISH
-	&& dek->algo != CIPHER_ALGO_BLOWFISH128
-	&& dek->algo != CIPHER_ALGO_CAST       )
-	return G10ERR_CIPHER_ALGO;
+    if( (rc=check_cipher_algo(dek->algo)) )
+	return rc;
     if( ed->len && ed->len < 10 )
 	log_bug("Nanu\n");   /* oops: found a bug */
 
-    if( dek->algo == CIPHER_ALGO_CAST ) {
-	dfx.is_cast5 = 1;
-	dfx.cast5_ctx = m_alloc_secure( sizeof *dfx.cast5_ctx );
-	cast5_setkey( dfx.cast5_ctx, dek->key, dek->keylen  );
-	cast5_setiv( dfx.cast5_ctx, NULL );
-    }
-    else {
-	dfx.is_cast5 = 0;
-	dfx.bf_ctx = m_alloc_secure( sizeof *dfx.bf_ctx );
-	blowfish_setkey( dfx.bf_ctx, dek->key, dek->keylen  );
-	blowfish_setiv( dfx.bf_ctx, NULL );
-    }
+    dfx.cipher_hd = cipher_open( dek->algo, CIPHER_MODE_AUTO_CFB, 1 );
+    cipher_setkey( dfx.cipher_hd, dek->key, dek->keylen  );
+    cipher_setiv( dfx.cipher_hd, NULL );
 
     if( ed->len ) {
 	iobuf_set_limit( ed->buf, ed->len );
@@ -93,15 +80,11 @@ decrypt_data( PKT_encrypted *ed, DEK *dek )
 	    else
 		temp[i] = c;
     }
-    if( dfx.is_cast5 ) {
-	cast5_decode_cfb( dfx.cast5_ctx, temp, temp, 10);
-	cast5_sync_cfb( dfx.cast5_ctx );
-    }
-    else
-	blowfish_decode_cfb( dfx.bf_ctx, temp, temp, 10);
+    cipher_decrypt( dfx.cipher_hd, temp, temp, 10);
+    cipher_sync( dfx.cipher_hd );
     p = temp;
     if( p[6] != p[8] || p[7] != p[9] ) {
-	m_free(dfx.bf_ctx);
+	cipher_close(dfx.cipher_hd);
 	return G10ERR_BAD_KEY;
     }
     iobuf_push_filter( ed->buf, decode_filter, &dfx );
@@ -112,7 +95,7 @@ decrypt_data( PKT_encrypted *ed, DEK *dek )
     else
 	iobuf_clear_eof( ed->buf );
     ed->buf = NULL;
-    m_free(dfx.bf_ctx);
+    cipher_close(dfx.cipher_hd);
     return 0;
 }
 
@@ -132,12 +115,8 @@ decode_filter( void *opaque, int control, IOBUF a, byte *buf, size_t *ret_len)
 	    buf[n] = c;
 	}
 
-	if( n ) {
-	    if( fc->is_cast5 )
-		cast5_decode_cfb( fc->cast5_ctx, buf, buf, n);
-	    else
-		blowfish_decode_cfb( fc->bf_ctx, buf, buf, n);
-	}
+	if( n )
+	    cipher_decrypt( fc->cipher_hd, buf, buf, n);
 	else
 	    rc = -1; /* eof */
 	*ret_len = n;
diff --git a/g10/filter.h b/g10/filter.h
index fac1e0e2b..1bd8ba050 100644
--- a/g10/filter.h
+++ b/g10/filter.h
@@ -60,8 +60,7 @@ typedef struct {
 typedef struct {
     DEK *dek;
     u32 datalen;
-    BLOWFISH_context *bf_ctx;
-    CAST5_context *cast5_ctx;
+    CIPHER_HANDLE cipher_hd;
     int header;
 } cipher_filter_context_t;
 
diff --git a/g10/getkey.c b/g10/getkey.c
index edc5c8355..7868df951 100644
--- a/g10/getkey.c
+++ b/g10/getkey.c
@@ -554,6 +554,7 @@ lookup( PKT_public_cert *pkc, int mode,  u32 *keyid, const char *name )
     int rc;
     KBNODE keyblock = NULL;
     KBPOS kbpos;
+    int oldmode = set_packet_list_mode(0);
 
     rc = enum_keyblocks( 0, &kbpos, &keyblock );
     if( rc ) {
@@ -655,6 +656,7 @@ lookup( PKT_public_cert *pkc, int mode,  u32 *keyid, const char *name )
   leave:
     enum_keyblocks( 2, &kbpos, &keyblock ); /* close */
     release_kbnode( keyblock );
+    set_packet_list_mode(oldmode);
     return rc;
 }
 
@@ -667,11 +669,12 @@ lookup_skc( PKT_secret_cert *skc, int mode,  u32 *keyid, const char *name )
     int rc;
     KBNODE keyblock = NULL;
     KBPOS kbpos;
+    int oldmode = set_packet_list_mode(0);
 
     rc = enum_keyblocks( 5 /* open secret */, &kbpos, &keyblock );
     if( rc ) {
 	if( rc == -1 )
-	    rc = G10ERR_NO_PUBKEY;
+	    rc = G10ERR_NO_SECKEY;
 	else if( rc )
 	    log_error("enum_keyblocks(open secret) failed: %s\n", g10_errstr(rc) );
 	goto leave;
@@ -761,13 +764,14 @@ lookup_skc( PKT_secret_cert *skc, int mode,  u32 *keyid, const char *name )
 	keyblock = NULL;
     }
     if( rc == -1 )
-	rc = G10ERR_NO_PUBKEY;
+	rc = G10ERR_NO_SECKEY;
     else if( rc )
 	log_error("enum_keyblocks(read) failed: %s\n", g10_errstr(rc));
 
   leave:
     enum_keyblocks( 2, &kbpos, &keyblock ); /* close */
     release_kbnode( keyblock );
+    set_packet_list_mode(oldmode);
     return rc;
 }
 
diff --git a/g10/keygen.c b/g10/keygen.c
index 293d70a58..003d54bbb 100644
--- a/g10/keygen.c
+++ b/g10/keygen.c
@@ -40,42 +40,6 @@
 #endif
 
 
-static u16
-checksum_u16( unsigned n )
-{
-    u16 a;
-
-    a  = (n >> 8) & 0xff;
-    a |= n & 0xff;
-    return a;
-}
-
-static u16
-checksum( byte *p, unsigned n )
-{
-    u16 a;
-
-    for(a=0; n; n-- )
-	a += *p++;
-    return a;
-}
-
-static u16
-checksum_mpi( MPI a )
-{
-    u16 csum;
-    byte *buffer;
-    unsigned nbytes;
-
-    buffer = mpi_get_buffer( a, &nbytes, NULL );
-    csum = checksum_u16( nbytes*8 );
-    csum += checksum( buffer, nbytes );
-    m_free( buffer );
-    return csum;
-}
-
-
-
 static void
 write_uid( KBNODE root, const char *s )
 {
diff --git a/g10/keyid.c b/g10/keyid.c
index 9f4ccdfb8..02e706fc2 100644
--- a/g10/keyid.c
+++ b/g10/keyid.c
@@ -64,16 +64,10 @@ v3_elg_fingerprint_md( PKT_public_cert *pkc )
 
     nb1 = mpi_get_nbits(pkc->d.elg.p);
     p1 = buf1 = mpi_get_buffer( pkc->d.elg.p, &n1, NULL );
-    for( ; !*p1 && n1; p1++, n1-- )  /* skip leading null bytes */
-	;
     nb2 = mpi_get_nbits(pkc->d.elg.g);
     p2 = buf2 = mpi_get_buffer( pkc->d.elg.g, &n2, NULL );
-    for( ; !*p2 && n2; p2++, n2-- )  /* skip leading null bytes */
-	;
     nb3 = mpi_get_nbits(pkc->d.elg.y);
     p3 = buf3 = mpi_get_buffer( pkc->d.elg.y, &n3, NULL );
-    for( ; !*p3 && n3; p3++, n3-- )  /* skip leading null bytes */
-	;
 
     /* calculate length of packet (1+4+2+1+2+n1+2+n2+2+n3) */
     n = 14 + n1 + n2 + n3;
@@ -117,16 +111,10 @@ elg_fingerprint_md( PKT_public_cert *pkc )
 
     nb1 = mpi_get_nbits(pkc->d.elg.p);
     p1 = buf1 = mpi_get_buffer( pkc->d.elg.p, &n1, NULL );
-    for( ; !*p1 && n1; p1++, n1-- )  /* skip leading null bytes */
-	;
     nb3 = mpi_get_nbits(pkc->d.elg.g);
     p3 = buf3 = mpi_get_buffer( pkc->d.elg.g, &n3, NULL );
-    for( ; !*p3 && n3; p3++, n3-- )
-	;
     nb4 = mpi_get_nbits(pkc->d.elg.y);
     p4 = buf4 = mpi_get_buffer( pkc->d.elg.y, &n4, NULL );
-    for( ; !*p4 && n4; p4++, n4-- )
-	;
 
     /* calculate length of packet */
     n = 12 + n1 + n3 +n4 ;
@@ -167,20 +155,12 @@ dsa_fingerprint_md( PKT_public_cert *pkc )
 
     nb1 = mpi_get_nbits(pkc->d.dsa.p);
     p1 = buf1 = mpi_get_buffer( pkc->d.dsa.p, &n1, NULL );
-    for( ; !*p1 && n1; p1++, n1-- )  /* skip leading null bytes */
-	;
     nb2 = mpi_get_nbits(pkc->d.dsa.q);
     p2 = buf2 = mpi_get_buffer( pkc->d.dsa.q, &n2, NULL );
-    for( ; !*p2 && n2; p2++, n2-- )
-	;
     nb3 = mpi_get_nbits(pkc->d.dsa.g);
     p3 = buf3 = mpi_get_buffer( pkc->d.dsa.g, &n3, NULL );
-    for( ; !*p3 && n3; p3++, n3-- )
-	;
     nb4 = mpi_get_nbits(pkc->d.dsa.y);
     p4 = buf4 = mpi_get_buffer( pkc->d.dsa.y, &n4, NULL );
-    for( ; !*p4 && n4; p4++, n4-- )
-	;
 
     /* calculate length of packet */
     n = 14 + n1 + n2 + n3 +n4 ;
@@ -510,13 +490,9 @@ fingerprint_from_pkc( PKT_public_cert *pkc, size_t *ret_len )
 
 	md = md_open( DIGEST_ALGO_MD5, 0);
 	p = buf = mpi_get_buffer( pkc->d.rsa.rsa_n, &n, NULL );
-	for( ; !*p && n; p++, n-- )
-	    ;
 	md_write( md, p, n );
 	m_free(buf);
 	p = buf = mpi_get_buffer( pkc->d.rsa.rsa_e, &n, NULL );
-	for( ; !*p && n; p++, n-- )
-	    ;
 	md_write( md, p, n );
 	m_free(buf);
 	md_final(md);
diff --git a/g10/main.h b/g10/main.h
index c162fd9cd..82f2373d7 100644
--- a/g10/main.h
+++ b/g10/main.h
@@ -21,6 +21,7 @@
 #define G10_MAIN_H
 #include "types.h"
 #include "iobuf.h"
+#include "mpi.h"
 #include "cipher.h"
 #include "keydb.h"
 
@@ -39,6 +40,11 @@ typedef struct {
   void g10_exit(int rc);
 #endif
 
+/*-- misc.c --*/
+u16 checksum_u16( unsigned n );
+u16 checksum( byte *p, unsigned n );
+u16 checksum_mpi( MPI a );
+
 /*-- encode.c --*/
 int encode_symmetric( const char *filename );
 int encode_store( const char *filename );
diff --git a/g10/misc.c b/g10/misc.c
new file mode 100644
index 000000000..7424039bd
--- /dev/null
+++ b/g10/misc.c
@@ -0,0 +1,63 @@
+/* misc.c -  miscellaneous functions
+ *	Copyright (C) 1998 Free Software Foundation, Inc.
+ *
+ * This file is part of GNUPG.
+ *
+ * GNUPG is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * GNUPG is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "util.h"
+#include "main.h"
+
+
+u16
+checksum_u16( unsigned n )
+{
+    u16 a;
+
+    a  = (n >> 8) & 0xff;
+    a |= n & 0xff;
+    return a;
+}
+
+u16
+checksum( byte *p, unsigned n )
+{
+    u16 a;
+
+    for(a=0; n; n-- )
+	a += *p++;
+    return a;
+}
+
+u16
+checksum_mpi( MPI a )
+{
+    u16 csum;
+    byte *buffer;
+    unsigned nbytes;
+
+    buffer = mpi_get_buffer( a, &nbytes, NULL );
+    csum = checksum_u16( mpi_get_nbits(a) );
+    csum += checksum( buffer, nbytes );
+    m_free( buffer );
+    return csum;
+}
+
+
diff --git a/g10/parse-packet.c b/g10/parse-packet.c
index fe2c63c5b..26c112244 100644
--- a/g10/parse-packet.c
+++ b/g10/parse-packet.c
@@ -61,19 +61,6 @@ static int  parse_compressed( IOBUF inp, int pkttype, unsigned long pktlen,
 							   PACKET *packet );
 static int  parse_encrypted( IOBUF inp, int pkttype, unsigned long pktlen,
 							   PACKET *packet );
-#if 0
-static u16
-checksum( byte *p )
-{
-    u16 n, a;
-
-    n = *p++ << 8;
-    n |= *p++;
-    for(a=0; n; n-- )
-	a += *p++;
-    return a;
-}
-#endif
 
 static unsigned short
 read_16(IOBUF inp)
@@ -944,6 +931,9 @@ parse_certificate( IOBUF inp, int pkttype, unsigned long pktlen,
 
 	    cert->csum = read_16(inp); pktlen -= 2;
 	    if( list_mode ) {
+	    printf("\telg x: ");
+	    mpi_print(stdout, cert->d.elg.x, mpi_print_mode  );
+	    putchar('\n');
 		printf("\t[secret value x is not shown]\n"
 		       "\tchecksum: %04hx\n", cert->csum);
 	    }
diff --git a/g10/pubkey-enc.c b/g10/pubkey-enc.c
index f19af2189..7fd3101bd 100644
--- a/g10/pubkey-enc.c
+++ b/g10/pubkey-enc.c
@@ -100,6 +100,8 @@ get_session_key( PKT_pubkey_enc *k, DEK *dek )
      *
      *	   0  2  RND(n bytes)  0  A  DEK(k bytes)  CSUM(2 bytes)
      *
+     * (mpi_get_buffer already removed the leading zero).
+     *
      * RND are non-zero randow bytes.
      * A   is the cipher algorithm
      * DEK is the encryption key (session key) with length k
@@ -107,8 +109,7 @@ get_session_key( PKT_pubkey_enc *k, DEK *dek )
      */
     if( DBG_CIPHER )
 	log_hexdump("DEK frame:", frame, nframe );
-    for(n=0; n < nframe && !frame[n]; n++ ) /* skip leading zeroes */
-	;
+    n=0;
     if( n + 7 > nframe )
 	{ rc = G10ERR_WRONG_SECKEY; goto leave; }
     if( frame[n] == 1 && frame[nframe-1] == 2 ) {
diff --git a/g10/seckey-cert.c b/g10/seckey-cert.c
index dada0fd20..a4ce96206 100644
--- a/g10/seckey-cert.c
+++ b/g10/seckey-cert.c
@@ -29,34 +29,8 @@
 #include "mpi.h"
 #include "keydb.h"
 #include "cipher.h"
-
-#if  BLOWFISH_BLOCKSIZE != 8
-  #error unsupported blocksize
-#endif
-#if  CAST5_BLOCKSIZE != 8
-  #error unsupported blocksize
-#endif
-
-static u16
-checksum_u16( unsigned n )
-{
-    u16 a;
-
-    a  = (n >> 8) & 0xff;
-    a |= n & 0xff;
-    return a;
-}
-
-static u16
-checksum( byte *p, unsigned n )
-{
-    u16 a;
-
-    for(a=0; n; n-- )
-	a += *p++;
-    return a;
-}
-
+#include "main.h"
+#include "options.h"
 
 
 static int
@@ -73,8 +47,7 @@ check_elg( PKT_secret_cert *cert )
     if( cert->is_protected ) { /* remove the protection */
 	DEK *dek = NULL;
 	MPI test_x;
-	BLOWFISH_context *blowfish_ctx=NULL;
-	CAST5_context *cast5_ctx=NULL;
+	CIPHER_HANDLE cipher_hd=NULL;
 
 	switch( cert->protect.algo ) {
 	  case CIPHER_ALGO_NONE: BUG(); break;
@@ -87,47 +60,37 @@ check_elg( PKT_secret_cert *cert )
 	    else
 		dek = get_passphrase_hash( keyid, NULL, NULL );
 
-	    if( cert->protect.algo == CIPHER_ALGO_CAST )
-		cast5_ctx = m_alloc_secure( sizeof *cast5_ctx );
-	    else
-		blowfish_ctx = m_alloc_secure( sizeof *blowfish_ctx );
-
-	    if( blowfish_ctx ) {
-		blowfish_setkey( blowfish_ctx, dek->key, dek->keylen );
-		blowfish_setiv( blowfish_ctx, NULL );
-	    }
-	    else {
-		cast5_setkey( cast5_ctx, dek->key, dek->keylen );
-		cast5_setiv( cast5_ctx, NULL );
-	    }
+	    cipher_hd = cipher_open( cert->protect.algo,
+				     CIPHER_MODE_AUTO_CFB, 1);
+	    cipher_setkey( cipher_hd, dek->key, dek->keylen );
+	    cipher_setiv( cipher_hd, NULL );
 	    m_free(dek); /* pw is in secure memory, so m_free() burns it */
 	    memcpy(save_iv, cert->protect.iv, 8 );
-	    if( blowfish_ctx )
-		blowfish_decode_cfb( blowfish_ctx, cert->protect.iv,
-						   cert->protect.iv, 8 );
-	    else
-		cast5_decode_cfb( cast5_ctx, cert->protect.iv,
-						cert->protect.iv, 8 );
+	    cipher_decrypt( cipher_hd, cert->protect.iv, cert->protect.iv, 8 );
 	    mpi_set_secure(cert->d.elg.x );
 	    /*fixme: maybe it is better to set the buffer secure with a
 	     * new get_buffer_secure() function */
 	    buffer = mpi_get_buffer( cert->d.elg.x, &nbytes, NULL );
-	    csum = checksum_u16( nbytes*8 );
-	    if( blowfish_ctx )
-		blowfish_decode_cfb( blowfish_ctx, buffer, buffer, nbytes );
-	    else
-		cast5_decode_cfb( cast5_ctx, buffer, buffer, nbytes );
-	    csum += checksum( buffer, nbytes );
+	    cipher_decrypt( cipher_hd, buffer, buffer, nbytes );
 	    test_x = mpi_alloc_secure( mpi_get_nlimbs(cert->d.elg.x) );
 	    mpi_set_buffer( test_x, buffer, nbytes, 0 );
+	    csum = checksum_mpi( test_x );
 	    m_free( buffer );
-	    m_free( cast5_ctx );
-	    m_free( blowfish_ctx );
+	    cipher_close( cipher_hd );
 	    /* now let's see wether we have used the right passphrase */
 	    if( csum != cert->csum ) {
-		mpi_free(test_x);
-		memcpy( cert->protect.iv, save_iv, 8 );
-		return G10ERR_BAD_PASS;
+		/* very bad kludge to work around an early bug */
+		csum -= checksum_u16( mpi_get_nbits(test_x) );
+		nbytes = mpi_get_nlimbs(test_x) * 4;
+		csum += checksum_u16( nbytes*8 );
+		if( csum != cert->csum ) {
+		    mpi_free(test_x);
+		    memcpy( cert->protect.iv, save_iv, 8 );
+		    return G10ERR_BAD_PASS;
+		}
+		if( !opt.batch )
+		    log_info("Probably you have an old key - use "
+			 "\"--change-passphrase\" to convert.\n");
 	    }
 
 	    skey.p = cert->d.elg.p;
@@ -151,12 +114,18 @@ check_elg( PKT_secret_cert *cert )
 	}
     }
     else { /* not protected */
-	buffer = mpi_get_buffer( cert->d.elg.x, &nbytes, NULL );
-	csum = checksum_u16( nbytes*8 );
-	csum += checksum( buffer, nbytes );
-	m_free( buffer );
-	if( csum != cert->csum )
-	    return G10ERR_CHECKSUM;
+	csum = checksum_mpi( cert->d.elg.x );
+	if( csum != cert->csum ) {
+	    /* very bad kludge to work around an early bug */
+	    csum -= checksum_u16( mpi_get_nbits(cert->d.elg.x) );
+	    nbytes = mpi_get_nlimbs(cert->d.elg.x) * 4;
+	    csum += checksum_u16( nbytes*8 );
+	    if( csum != cert->csum )
+		return G10ERR_CHECKSUM;
+	    if( !opt.batch )
+		 log_info("Probably you have an old key - use "
+		     "\"--change-passphrase\" to convert.\n");
+	}
     }
 
     return 0;
@@ -177,8 +146,7 @@ check_dsa( PKT_secret_cert *cert )
     if( cert->is_protected ) { /* remove the protection */
 	DEK *dek = NULL;
 	MPI test_x;
-	BLOWFISH_context *blowfish_ctx=NULL;
-	CAST5_context *cast5_ctx=NULL;
+	CIPHER_HANDLE cipher_hd=NULL;
 
 	switch( cert->protect.algo ) {
 	  case CIPHER_ALGO_NONE: BUG(); break;
@@ -191,39 +159,23 @@ check_dsa( PKT_secret_cert *cert )
 	    else
 		dek = get_passphrase_hash( keyid, NULL, NULL );
 
-	    if( cert->protect.algo == CIPHER_ALGO_CAST ) {
-		cast5_ctx = m_alloc_secure( sizeof *cast5_ctx );
-		cast5_setkey( cast5_ctx, dek->key, dek->keylen );
-		cast5_setiv( cast5_ctx, NULL );
-	    }
-	    else {
-		blowfish_ctx = m_alloc_secure( sizeof *blowfish_ctx );
-		blowfish_setkey( blowfish_ctx, dek->key, dek->keylen );
-		blowfish_setiv( blowfish_ctx, NULL );
-	    }
+	    cipher_hd = cipher_open( cert->protect.algo,
+				     CIPHER_MODE_AUTO_CFB, 1);
+	    cipher_setkey( cipher_hd, dek->key, dek->keylen );
+	    cipher_setiv( cipher_hd, NULL );
 	    m_free(dek); /* pw is in secure memory, so m_free() burns it */
 	    memcpy(save_iv, cert->protect.iv, 8 );
-	    if( blowfish_ctx )
-		blowfish_decode_cfb( blowfish_ctx, cert->protect.iv,
-						   cert->protect.iv, 8 );
-	    else
-		cast5_decode_cfb( cast5_ctx, cert->protect.iv,
-					     cert->protect.iv, 8 );
+	    cipher_decrypt( cipher_hd, cert->protect.iv, cert->protect.iv, 8 );
 	    mpi_set_secure(cert->d.dsa.x );
 	    /*fixme: maybe it is better to set the buffer secure with a
 	     * new get_buffer_secure() function */
 	    buffer = mpi_get_buffer( cert->d.dsa.x, &nbytes, NULL );
-	    csum = checksum_u16( nbytes*8 );
-	    if( blowfish_ctx )
-		blowfish_decode_cfb( blowfish_ctx, buffer, buffer, nbytes );
-	    else
-		cast5_decode_cfb( cast5_ctx, buffer, buffer, nbytes );
-	    csum += checksum( buffer, nbytes );
+	    cipher_decrypt( cipher_hd, buffer, buffer, nbytes );
 	    test_x = mpi_alloc_secure( mpi_get_nlimbs(cert->d.dsa.x) );
 	    mpi_set_buffer( test_x, buffer, nbytes, 0 );
+	    csum = checksum_mpi( test_x );
 	    m_free( buffer );
-	    m_free( cast5_ctx );
-	    m_free( blowfish_ctx );
+	    cipher_close( cipher_hd );
 	    /* now let's see wether we have used the right passphrase */
 	    if( csum != cert->csum ) {
 		mpi_free(test_x);
@@ -253,10 +205,7 @@ check_dsa( PKT_secret_cert *cert )
 	}
     }
     else { /* not protected */
-	buffer = mpi_get_buffer( cert->d.dsa.x, &nbytes, NULL );
-	csum = checksum_u16( nbytes*8 );
-	csum += checksum( buffer, nbytes );
-	m_free( buffer );
+	csum = checksum_mpi( cert->d.dsa.x );
 	if( csum != cert->csum )
 	    return G10ERR_CHECKSUM;
     }
@@ -267,6 +216,9 @@ check_dsa( PKT_secret_cert *cert )
 
 
 #ifdef HAVE_RSA_CIPHER
+/****************
+ * FIXME: fix checksum stuff
+ */
 static int
 check_rsa( PKT_secret_cert *cert )
 {
@@ -398,23 +350,29 @@ is_secret_key_protected( PKT_secret_cert *cert )
 
 
 static int
-do_protect( void (*fnc)(void *, byte *, byte *, unsigned),
-	    void *fncctx, PKT_secret_cert *cert )
+do_protect( void (*fnc)(CIPHER_HANDLE, byte *, byte *, unsigned),
+	    CIPHER_HANDLE fnc_hd, PKT_secret_cert *cert )
 {
     byte *buffer;
     unsigned nbytes;
 
     switch( cert->pubkey_algo ) {
       case PUBKEY_ALGO_ELGAMAL:
+	/* recalculate the checksum, so that --change-passphrase
+	 * can be used to convert from the faulty to the correct one
+	 * wk 06.04.98:
+	 * fixme: remove this some time in the future.
+	 */
+	cert->csum = checksum_mpi( cert->d.elg.x );
 	buffer = mpi_get_buffer( cert->d.elg.x, &nbytes, NULL );
-	(*fnc)( fncctx, buffer, buffer, nbytes );
+	(*fnc)( fnc_hd, buffer, buffer, nbytes );
 	mpi_set_buffer( cert->d.elg.x, buffer, nbytes, 0 );
 	m_free( buffer );
 	break;
 
       case PUBKEY_ALGO_DSA:
 	buffer = mpi_get_buffer( cert->d.dsa.x, &nbytes, NULL );
-	(*fnc)( fncctx, buffer, buffer, nbytes );
+	(*fnc)( fnc_hd, buffer, buffer, nbytes );
 	mpi_set_buffer( cert->d.dsa.x, buffer, nbytes, 0 );
 	m_free( buffer );
 	break;
@@ -437,33 +395,20 @@ protect_secret_key( PKT_secret_cert *cert, DEK *dek )
 	return 0;
 
     if( !cert->is_protected ) { /* okay, apply the protection */
-	BLOWFISH_context *blowfish_ctx=NULL;
-	CAST5_context *cast5_ctx=NULL;
+	CIPHER_HANDLE cipher_hd=NULL;
 
 	switch( cert->protect.algo ) {
 	  case CIPHER_ALGO_NONE: BUG(); break;
 	  case CIPHER_ALGO_BLOWFISH:
-	    blowfish_ctx = m_alloc_secure( sizeof *blowfish_ctx );
-	    blowfish_setkey( blowfish_ctx, dek->key, dek->keylen );
-	    blowfish_setiv( blowfish_ctx, NULL );
-	    blowfish_encode_cfb( blowfish_ctx, cert->protect.iv,
-					       cert->protect.iv, 8 );
-	    if( !do_protect( (void (*)(void*,byte*,byte*,unsigned))
-			     &blowfish_encode_cfb, blowfish_ctx, cert ) )
-		cert->is_protected = 1;
-	    m_free( blowfish_ctx );
-	    break;
-
 	  case CIPHER_ALGO_CAST:
-	    cast5_ctx = m_alloc_secure( sizeof *cast5_ctx );
-	    cast5_setkey( cast5_ctx, dek->key, dek->keylen );
-	    cast5_setiv( cast5_ctx, NULL );
-	    cast5_encode_cfb( cast5_ctx, cert->protect.iv,
-					       cert->protect.iv, 8 );
-	    if( !do_protect( (void (*)(void*,byte*,byte*,unsigned))
-			     &cast5_encode_cfb, cast5_ctx, cert ) )
+	    cipher_hd = cipher_open( cert->protect.algo,
+				     CIPHER_MODE_AUTO_CFB, 1 );
+	    cipher_setkey( cipher_hd, dek->key, dek->keylen );
+	    cipher_setiv( cipher_hd, NULL );
+	    cipher_encrypt( cipher_hd, cert->protect.iv, cert->protect.iv, 8 );
+	    if( !do_protect( &cipher_encrypt, cipher_hd, cert ) )
 		cert->is_protected = 1;
-	    m_free( cast5_ctx );
+	    cipher_close( cipher_hd );
 	    break;
 
 	  default:
diff --git a/g10/seskey.c b/g10/seskey.c
index b17302ea5..4ce8fe03b 100644
--- a/g10/seskey.c
+++ b/g10/seskey.c
@@ -78,6 +78,9 @@ encode_session_key( DEK *dek, unsigned nbits )
      *
      *	   0  2  RND(n bytes)  0  A  DEK(k bytes)  CSUM(2 bytes)
      *
+     * (But how can we store the leading 0 - the external representaion
+     *	of MPIs don't allow leading zeroes =:-)
+     *
      * RND are non-zero random bytes.
      * A   is the cipher algorithm
      * DEK is the encryption key (session key) length k depends on the