X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/f1e05cc79778c693a1a2bad478ced44791922cce..8d6d5106a6f1bcba010877d55932a8d8dcfa88bd:/src/src/auths/heimdal_gssapi.c

diff --git a/src/src/auths/heimdal_gssapi.c b/src/src/auths/heimdal_gssapi.c
index 9021509dd..94e689d58 100644
--- a/src/src/auths/heimdal_gssapi.c
+++ b/src/src/auths/heimdal_gssapi.c
@@ -2,7 +2,7 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) University of Cambridge 1995 - 2012 */
+/* Copyright (c) University of Cambridge 1995 - 2015 */
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Copyright (c) Twitter Inc 2012
@@ -43,7 +43,9 @@ Without rename, we could add an option for GS2 support in the future.
 
 #ifndef AUTH_HEIMDAL_GSSAPI
 /* dummy function to satisfy compilers when we link in an "empty" file. */
-static void dummy(int x) { dummy(x-1); }
+static void dummy(int x);
+static void dummy2(int x) { dummy(x-1); }
+static void dummy(int x) { dummy2(x-1); }
 #else
 
 #include <gssapi/gssapi.h>
@@ -318,7 +320,7 @@ auth_heimdal_gssapi_server(auth_instance *ablock, uschar *initial_data)
         break;
 
       case 1:
-        gbufdesc_in.length = auth_b64decode(from_client, USS &gbufdesc_in.value);
+        gbufdesc_in.length = b64decode(from_client, USS &gbufdesc_in.value);
         if (gclient) {
           maj_stat = gss_release_name(&min_stat, &gclient);
           gclient = GSS_C_NO_NAME;
@@ -398,7 +400,7 @@ auth_heimdal_gssapi_server(auth_instance *ablock, uschar *initial_data)
         break;
 
       case 3:
-        gbufdesc_in.length = auth_b64decode(from_client, USS &gbufdesc_in.value);
+        gbufdesc_in.length = b64decode(from_client, USS &gbufdesc_in.value);
         maj_stat = gss_unwrap(&min_stat,
             gcontext,
             &gbufdesc_in,       /* data from client */
@@ -412,10 +414,10 @@ auth_heimdal_gssapi_server(auth_instance *ablock, uschar *initial_data)
           error_out = FAIL;
           goto ERROR_OUT;
         }
-        if (gbufdesc_out.length < 5) {
+        if (gbufdesc_out.length < 4) {
           HDEBUG(D_auth)
             debug_printf("gssapi: final message too short; "
-                "need flags, buf sizes and authzid\n");
+                "need flags, buf sizes and optional authzid\n");
           error_out = FAIL;
           goto ERROR_OUT;
         }
@@ -434,14 +436,17 @@ auth_heimdal_gssapi_server(auth_instance *ablock, uschar *initial_data)
 
         /* Identifiers:
         The SASL provided identifier is an unverified authzid.
-        GSSAPI provides us with a verified identifier.
+        GSSAPI provides us with a verified identifier, but it might be empty
+        for some clients.
         */
 
         /* $auth2 is authzid requested at SASL layer */
-        expand_nlength[2] = gbufdesc_out.length - 4;
-        auth_vars[1] = expand_nstring[2] =
-          string_copyn((US gbufdesc_out.value) + 4, expand_nlength[2]);
-        expand_nmax = 2;
+        if (gbufdesc_out.length > 4) {
+          expand_nlength[2] = gbufdesc_out.length - 4;
+          auth_vars[1] = expand_nstring[2] =
+            string_copyn((US gbufdesc_out.value) + 4, expand_nlength[2]);
+          expand_nmax = 2;
+        }
 
         gss_release_buffer(&min_stat, &gbufdesc_out);
         EmptyBuf(gbufdesc_out);
@@ -464,6 +469,14 @@ auth_heimdal_gssapi_server(auth_instance *ablock, uschar *initial_data)
         auth_vars[0] = expand_nstring[1] =
           string_copyn(gbufdesc_out.value, gbufdesc_out.length);
 
+        if (expand_nmax == 0) { /* should be: authzid was empty */
+          expand_nmax = 2;
+          expand_nlength[2] = expand_nlength[1];
+          auth_vars[1] = expand_nstring[2] = string_copyn(expand_nstring[1], expand_nlength[1]);
+          HDEBUG(D_auth)
+            debug_printf("heimdal SASL: empty authzid, set to dup of GSSAPI display name\n");
+        }
+
         HDEBUG(D_auth)
           debug_printf("heimdal SASL: happy with client request\n"
              "  auth1 (verified GSSAPI display-name): \"%s\"\n"
@@ -515,7 +528,7 @@ exim_gssapi_error_defer(uschar *store_reset_point,
   va_start(ap, format);
   if (!string_vformat(buffer, sizeof(buffer), format, ap))
     log_write(0, LOG_MAIN|LOG_PANIC_DIE,
-        "exim_gssapi_error_defer expansion larger than %d",
+        "exim_gssapi_error_defer expansion larger than %lu",
         sizeof(buffer));
   va_end(ap);