Catch corruption in HKP index lines (can be caused by broken or malicious

keyservers).

Add KEYSERVER_NOT_SUPPORTED for unsupported actions (say, a keyserver that
has no way to search, or a readonly keyserver that has no way to add).
Also add a USE_EXTERNAL_HKP define to disable the internal HKP keyserver
code.

g10/ChangeLog

@@ -1,3 +1,14 @@
+2002-02-19  David Shaw  <dshaw@jabberwocky.com>
+
+	* hkp.c (parse_hkp_index): Catch corruption in HKP index lines
+	(can be caused by broken or malicious keyservers).
+
+	* keyserver.c (keyserver_work): Add KEYSERVER_NOT_SUPPORTED for
+	unsupported actions (say, a keyserver that has no way to search,
+	or a readonly keyserver that has no way to add).  Also add a
+	USE_EXTERNAL_HKP define to disable the internal HKP keyserver
+	code.
+
 2002-02-14  Werner Koch  <wk@gnupg.org>
 
 	* g10.c: New option --no-use-agent. 

g10/hkp.c

@@ -337,6 +337,12 @@ parse_hkp_index(IOBUF buffer,char *line)
     {
       int uidindex=0;
 
+      if(line==NULL)
+	{
+	  uid=m_strdup("Key index corrupted");
+	  return ret;
+	}
+
       /* All that's left is the user name.  Strip off anything
 	 <between brackets> and de-urlencode it. */
 

g10/keyserver.c

@@ -538,6 +538,7 @@ keyserver_work(int action,STRLIST list,u32 (*kidlist)[2],int count)
       return G10ERR_BAD_URI;
     }
 
+#ifndef USE_EXTERNAL_HKP
   /* Use the internal HKP code */
   if(strcasecmp(opt.keyserver_scheme,"x-hkp")==0 ||
      strcasecmp(opt.keyserver_scheme,"hkp")==0 ||
@@ -563,6 +564,7 @@ keyserver_work(int action,STRLIST list,u32 (*kidlist)[2],int count)
 
       return 0;
     }
+#endif
 
   /* It's not the internal HKP code, so try and spawn a handler for it */
 
@@ -576,6 +578,13 @@ keyserver_work(int action,STRLIST list,u32 (*kidlist)[2],int count)
 		    opt.keyserver_scheme);
 	  break;
 
+	case KEYSERVER_NOT_SUPPORTED:
+	  log_error(_("action \"%s\" not supported with keyserver "
+		      "scheme \"%s\"\n"),
+		    action==GET?"get":action==SEND?"send":
+		    action==SEARCH?"search":"unknown",
+		    opt.keyserver_scheme);
+
 	case KEYSERVER_INTERNAL_ERROR:
 	default:
 	  log_error(_("keyserver internal error\n"));

include/ChangeLog

@@ -1,3 +1,9 @@
+2002-02-19  David Shaw  <dshaw@jabberwocky.com>
+
+	* keyserver.h: Add KEYSERVER_NOT_SUPPORTED for unsupported actions
+	(say, a keyserver that has no way to search, or a readonly
+	keyserver that has no way to add).
+
 2002-01-02  Stefan Bellon  <sbellon@sbellon.de>
 
 	* util.h [__riscos__]: Updated prototype list.

include/keyserver.h

@@ -24,7 +24,8 @@
 /* Return codes */
 #define KEYSERVER_OK               0
 #define KEYSERVER_INTERNAL_ERROR   1
-#define KEYSERVER_VERSION_ERROR    2
+#define KEYSERVER_NOT_SUPPORTED    2
+#define KEYSERVER_VERSION_ERROR    3
 #define KEYSERVER_SCHEME_NOT_FOUND 127
 
 #endif /* !_KEYSERVER_H_ */