* keyserver-internal.h, keyserver.c (keyserver_import_pka): Use the
authorDavid Shaw <dshaw@jabberwocky.com>
Tue, 14 Mar 2006 03:16:21 +0000 (03:16 +0000)
committerDavid Shaw <dshaw@jabberwocky.com>
Tue, 14 Mar 2006 03:16:21 +0000 (03:16 +0000)
same API as the other auto-key-locate fetchers.

* getkey.c (get_pubkey_byname): Use the fingerprint of the key that we
actually fetched.  This helps prevent problems where the key that we
fetched doesn't have the same name that we used to fetch it.  In the
case of CERT and PKA, this is an actual security requirement as the
URL might point to a key put in by an attacker.  By forcing the use of
the fingerprint, we won't use the attacker's key here.

g10/ChangeLog
g10/getkey.c
g10/keyserver-internal.h
g10/keyserver.c

index 2f7bee3..d3df255 100644 (file)
@@ -1,5 +1,16 @@
 2006-03-13  David Shaw  <dshaw@jabberwocky.com>
 
+       * keyserver-internal.h, keyserver.c (keyserver_import_pka): Use
+       the same API as the other auto-key-locate fetchers.
+
+       * getkey.c (get_pubkey_byname): Use the fingerprint of the key
+       that we actually fetched.  This helps prevent problems where the
+       key that we fetched doesn't have the same name that we used to
+       fetch it.  In the case of CERT and PKA, this is an actual security
+       requirement as the URL might point to a key put in by an attacker.
+       By forcing the use of the fingerprint, we won't use the attacker's
+       key here.
+
        * keyserver-internal.h, keyserver.c (keyserver_spawn,
        keyserver_work, keyserver_import_cert, keyserver_import_name,
        keyserver_import_ldap): Pass fingerprint info through.
index 1805eb0..8594ad9 100644 (file)
@@ -922,11 +922,14 @@ get_pubkey_byname (PKT_public_key *pk,
 
       for(akl=opt.auto_key_locate;akl;akl=akl->next)
        {
+         unsigned char *fpr;
+         size_t fpr_len;
+
          switch(akl->type)
            {
            case AKL_CERT:
              glo_ctrl.in_auto_key_retrieve++;
-             res=keyserver_import_cert(name,NULL,NULL);
+             res=keyserver_import_cert(name,&fpr,&fpr_len);
              glo_ctrl.in_auto_key_retrieve--;
 
              if(res==0)
@@ -935,35 +938,17 @@ get_pubkey_byname (PKT_public_key *pk,
              break;
 
            case AKL_PKA:
-             {
-               unsigned char fpr[MAX_FINGERPRINT_LEN];
-
-               glo_ctrl.in_auto_key_retrieve++;
-               res=keyserver_import_pka(name,fpr);
-               glo_ctrl.in_auto_key_retrieve--;
-
-               if(res==0)
-                 {
-                   int i;
-                   char fpr_string[MAX_FINGERPRINT_LEN*2+1];
-
-                   log_info(_("Automatically retrieved `%s' via %s\n"),
-                            name,"PKA");
-
-                   free_strlist(namelist);
-                   namelist=NULL;
-
-                   for(i=0;i<MAX_FINGERPRINT_LEN;i++)
-                     sprintf(fpr_string+2*i,"%02X",fpr[i]);
+             glo_ctrl.in_auto_key_retrieve++;
+             res=keyserver_import_pka(name,&fpr,&fpr_len);
 
-                   add_to_strlist( &namelist, fpr_string );
-                 }
-             }
+             if(res==0)
+               log_info(_("Automatically retrieved `%s' via %s\n"),
+                        name,"PKA");
              break;
 
            case AKL_LDAP:
              glo_ctrl.in_auto_key_retrieve++;
-             res=keyserver_import_ldap(name,NULL,NULL);
+             res=keyserver_import_ldap(name,&fpr,&fpr_len);
              glo_ctrl.in_auto_key_retrieve--;
 
              if(res==0)
@@ -979,7 +964,7 @@ get_pubkey_byname (PKT_public_key *pk,
              if(opt.keyserver)
                {
                  glo_ctrl.in_auto_key_retrieve++;
-                 res=keyserver_import_name(name,NULL,NULL,opt.keyserver);
+                 res=keyserver_import_name(name,&fpr,&fpr_len,opt.keyserver);
                  glo_ctrl.in_auto_key_retrieve--;
 
                  if(res==0)
@@ -994,7 +979,7 @@ get_pubkey_byname (PKT_public_key *pk,
 
                keyserver=keyserver_match(akl->spec);
                glo_ctrl.in_auto_key_retrieve++;
-               res=keyserver_import_name(name,NULL,NULL,keyserver);
+               res=keyserver_import_name(name,&fpr,&fpr_len,keyserver);
                glo_ctrl.in_auto_key_retrieve--;
 
                if(res==0)
@@ -1004,6 +989,34 @@ get_pubkey_byname (PKT_public_key *pk,
              break;
            }
 
+         /* Use the fingerprint of the key that we actually fetched.
+            This helps prevent problems where the key that we fetched
+            doesn't have the same name that we used to fetch it.  In
+            the case of CERT and PKA, this is an actual security
+            requirement as the URL might point to a key put in by an
+            attacker.  By forcing the use of the fingerprint, we
+            won't use the attacker's key here. */
+         if(res==0 && fpr)
+           {
+             int i;
+             char fpr_string[MAX_FINGERPRINT_LEN*2+1];
+
+             assert(fpr_len<=MAX_FINGERPRINT_LEN);
+
+             free_strlist(namelist);
+             namelist=NULL;
+
+             for(i=0;i<fpr_len;i++)
+               sprintf(fpr_string+2*i,"%02X",fpr[i]);
+
+             if(opt.verbose)
+               log_info("auto-key-locate found fingerprint %s\n",fpr_string);
+
+             add_to_strlist( &namelist, fpr_string );
+
+             xfree(fpr);
+           }
+
          rc = key_byname( NULL, namelist, pk, NULL, 0,
                           include_unusable, ret_keyblock, ret_kdbhd);
          if(rc!=G10ERR_NO_PUBKEY)
index 9b6def8..a365986 100644 (file)
@@ -45,7 +45,7 @@ int keyserver_search(STRLIST tokens);
 int keyserver_fetch(STRLIST urilist);
 int keyserver_import_cert(const char *name,
                          unsigned char **fpr,size_t *fpr_len);
-int keyserver_import_pka(const char *name,unsigned char *fpr);
+int keyserver_import_pka(const char *name,unsigned char **fpr,size_t *fpr_len);
 int keyserver_import_name(const char *name,unsigned char **fpr,size_t *fpr_len,
                          struct keyserver_spec *keyserver);
 int keyserver_import_ldap(const char *name,
index b4a8c14..31037c0 100644 (file)
@@ -2036,24 +2036,30 @@ keyserver_import_cert(const char *name,unsigned char **fpr,size_t *fpr_len)
 /* Import key pointed to by a PKA record. Return the requested
    fingerprint in fpr. */
 int
-keyserver_import_pka(const char *name,unsigned char *fpr)
+keyserver_import_pka(const char *name,unsigned char **fpr,size_t *fpr_len)
 {
   char *uri;
   int rc=-1;
 
-  uri = get_pka_info (name, fpr);
+  *fpr=xmalloc(20);
+  *fpr_len=20;
+
+  uri = get_pka_info (name, *fpr);
   if (uri)
     {
       struct keyserver_spec *spec;
       spec = parse_keyserver_uri (uri, 1, NULL, 0);
       if (spec)
        {
-         rc=keyserver_import_fprint (fpr, 20, spec);
+         rc=keyserver_import_fprint (*fpr, 20, spec);
          free_keyserver_spec (spec);
        }
       xfree (uri);
     }
 
+  if(rc!=0)
+    xfree(*fpr);
+
   return rc;
 }