* http.h, http.c (send_request): Pass in srvtag and make its presence

sufficient to turn the feature on.  (http_open): From here.
(http_document): And here.

* gpgkeys_hkp.c (srv_replace): New function to transform a SRV
hostname to a real hostname.  (main): Call it from here for the
HAVE_LIBCURL case (without libcurl is handled via the curl-shim).

* curl-shim.h, curl-shim.c (curl_easy_setopt, curl_easy_perform): Add
a CURLOPT_SRVTAG_GPG_HACK (passed through the the http engine).

4 files changed, 99 insertions, 20 deletions

diff --git a/keyserver/ChangeLog b/keyserver/ChangeLog
index 2b403379d..26abf0fba 100644
--- a/keyserver/ChangeLog
+++ b/keyserver/ChangeLog
@@ -1,3 +1,16 @@
+2009-05-27  David Shaw  <dshaw@jabberwocky.com>
+
+	From 1.4:
+
+	* gpgkeys_hkp.c (srv_replace): New function to transform a SRV
+	hostname to a real hostname.
+	(main): Call it from here for the HAVE_LIBCURL case (without
+	libcurl is handled via the curl-shim).
+
+	* curl-shim.h, curl-shim.c (curl_easy_setopt, curl_easy_perform):
+	Add a CURLOPT_SRVTAG_GPG_HACK (passed through the the http
+	engine).
+
 2009-05-10  David Shaw  <dshaw@jabberwocky.com>
 
 	From 1.4:
diff --git a/keyserver/curl-shim.c b/keyserver/curl-shim.c
index 0c8bfdc9b..98b5b24c7 100644
--- a/keyserver/curl-shim.c
+++ b/keyserver/curl-shim.c
@@ -144,6 +144,9 @@ curl_easy_setopt(CURL *curl,CURLoption option,...)
     case CURLOPT_POSTFIELDS:
       curl->postfields=va_arg(ap,char *);
       break;
+    case CURLOPT_SRVTAG_GPG_HACK:
+      curl->srvtag=va_arg(ap,char *);
+      break;
     case CURLOPT_FAILONERROR:
       curl->flags.failonerror=va_arg(ap,long)?1:0;
       break;
@@ -193,7 +196,7 @@ curl_easy_perform(CURL *curl)
   if(curl->flags.post)
     {
       rc = http_open (&curl->hd, HTTP_REQ_POST, curl->url, curl->auth,
-                      0, proxy, NULL);
+                      0, proxy, NULL, curl->srvtag);
       if (!rc)
 	{
 	  unsigned int post_len = strlen(curl->postfields);
@@ -216,7 +219,7 @@ curl_easy_perform(CURL *curl)
   else
     {
       rc = http_open (&curl->hd, HTTP_REQ_GET, curl->url, curl->auth,
-                      0, proxy, NULL);
+                      0, proxy, NULL, curl->srvtag);
       if (!rc)
 	{
 	  rc = http_wait_response (curl->hd);
diff --git a/keyserver/curl-shim.h b/keyserver/curl-shim.h
index 3b254ac03..793d484b9 100644
--- a/keyserver/curl-shim.h
+++ b/keyserver/curl-shim.h
@@ -48,7 +48,8 @@ typedef enum
     CURLOPT_CAINFO,
     CURLOPT_POST,
     CURLOPT_POSTFIELDS,
-    CURLOPT_FAILONERROR
+    CURLOPT_FAILONERROR,
+    CURLOPT_SRVTAG_GPG_HACK
   } CURLoption;
 
 typedef size_t (*write_func)(char *buffer,size_t size,
@@ -63,6 +64,7 @@ typedef struct
   write_func writer;
   void *file;
   char *postfields;
+  char *srvtag;
   unsigned int status;
   FILE *errors;
   struct
diff --git a/keyserver/gpgkeys_hkp.c b/keyserver/gpgkeys_hkp.c
index ef6fd7cb4..0764fe2ac 100644
--- a/keyserver/gpgkeys_hkp.c
+++ b/keyserver/gpgkeys_hkp.c
@@ -43,6 +43,9 @@
 #else
 #include "curl-shim.h"
 #endif
+#ifdef USE_DNS_SRV
+#include "srv.h"
+#endif
 #include "keyserver.h"
 #include "ksutil.h"
 
@@ -183,6 +186,7 @@ send_key(int *r_eof)
   strcat(key,encoded_key);
 
   strcpy(request,proto);
+  strcat(request,"://");
   strcat(request,opt->host);
   strcat(request,":");
   strcat(request,port);
@@ -247,6 +251,7 @@ get_key(char *getkey)
     }
 
   strcpy(request,proto);
+  strcat(request,"://");
   strcat(request,opt->host);
   strcat(request,":");
   strcat(request,port);
@@ -325,6 +330,7 @@ get_name(const char *getkey)
   fprintf(output,"NAME %s BEGIN\n",getkey);
 
   strcpy(request,proto);
+  strcat(request,"://");
   strcat(request,opt->host);
   strcat(request,":");
   strcat(request,port);
@@ -408,6 +414,7 @@ search_key(const char *searchkey)
   fprintf(output,"SEARCH %s BEGIN\n",searchkey);
 
   strcpy(request,proto);
+  strcat(request,"://");
   strcat(request,opt->host);
   strcat(request,":");
   strcat(request,port);
@@ -478,6 +485,51 @@ fail_all(struct keylist *keylist,int err)
       }
 }
 
+#ifdef HAVE_LIBCURL
+/* If there is a SRV record, take the highest ranked possibility.
+   This is a hack, as we don't proceed downwards. */
+static void
+srv_replace(void)
+{
+#ifdef USE_DNS_SRV
+  struct srventry *srvlist=NULL;
+  int srvcount;
+
+  if(1+strlen(opt->scheme)+6+strlen(opt->host)+1<=MAXDNAME)
+    {
+      char srvname[MAXDNAME];
+
+      strcpy(srvname,"_");
+      strcat(srvname,opt->scheme);
+      strcat(srvname,"._tcp.");
+      strcat(srvname,opt->host);
+      srvcount=getsrv(srvname,&srvlist);
+    }
+
+  if(srvlist)
+    {
+      char *newname,*newport;
+
+      newname=strdup(srvlist->target);
+      newport=malloc(MAX_PORT);
+      if(newname && newport)
+	{
+	  free(opt->host);
+	  free(opt->port);
+	  opt->host=newname;
+	  snprintf(newport,MAX_PORT,"%u",srvlist->port);
+	  opt->port=newport;
+	}
+      else
+	{
+	  free(newname);
+	  free(newport);
+	}
+    }
+#endif
+}
+#endif
+
 static void 
 show_help (FILE *fp)
 {
@@ -490,7 +542,7 @@ show_help (FILE *fp)
 int
 main(int argc,char *argv[])
 {
-  int arg,ret=KEYSERVER_INTERNAL_ERROR;
+  int arg,ret=KEYSERVER_INTERNAL_ERROR,try_srv=1;
   char line[MAX_LINE];
   int failed=0;
   struct keylist *keylist=NULL,*keyptr=NULL;
@@ -604,15 +656,14 @@ main(int argc,char *argv[])
 		    }
 		}
 	    }
-#if 0
 	  else if(strcasecmp(start,"try-dns-srv")==0)
 	    {
 	      if(no)
-		http_flags&=~HTTP_FLAG_TRY_SRV;
+		try_srv=0;
 	      else
-		http_flags|=HTTP_FLAG_TRY_SRV;
+		try_srv=1;
 	    }
-#endif
+
 	  continue;
 	}
     }
@@ -626,18 +677,15 @@ main(int argc,char *argv[])
 
   if(ks_strcasecmp(opt->scheme,"hkps")==0)
     {
-      proto="https://";
+      proto="https";
       port="443";
     }
   else
     {
-      proto="http://";
+      proto="http";
       port="11371";
     }
 
-  if(opt->port)
-    port=opt->port;
-
   if(!opt->host)
     {
       fprintf(console,"gpgkeys: no keyserver host provided\n");
@@ -659,6 +707,26 @@ main(int argc,char *argv[])
       goto fail;
     }
 
+  /* If the user gives a :port, then disable SRV.  The semantics of a
+     specified port and SRV do not play well together. */
+  if(opt->port)
+    port=opt->port;
+  else if(try_srv)
+    {
+#ifdef HAVE_LIBCURL
+      /* We're using libcurl, so fake SRV support via our wrapper.
+	 This isn't as good as true SRV support, as we do not try all
+	 possible targets at one particular level and work our way
+	 down the list, but it's better than nothing. */      
+      srv_replace();
+#else
+      /* We're using our internal curl shim, so we can use its (true)
+	 SRV support.  Obviously, CURLOPT_SRVTAG_GPG_HACK isn't a real
+	 libcurl option.  It's specific to our shim. */
+      curl_easy_setopt(curl,CURLOPT_SRVTAG_GPG_HACK,opt->scheme);
+#endif
+    }
+
   curl_easy_setopt(curl,CURLOPT_ERRORBUFFER,errorbuffer);
 
   if(opt->auth)
@@ -677,13 +745,6 @@ main(int argc,char *argv[])
   if(proxy)
     curl_easy_setopt(curl,CURLOPT_PROXY,proxy);
 
-#if 0
-  /* By suggested convention, if the user gives a :port, then disable
-     SRV. */
-  if(opt->port)
-    http_flags&=~HTTP_FLAG_TRY_SRV;
-#endif
-
   /* If it's a GET or a SEARCH, the next thing to come in is the
      keyids.  If it's a SEND, then there are no keyids. */