- markus@cvs.openbsd.org 2003/11/17 11:06:07

     [auth2-gss.c gss-genr.c gss-serv.c monitor.c monitor.h monitor_wrap.c]
     [monitor_wrap.h sshconnect2.c ssh-gss.h]
     replace "gssapi" with "gssapi-with-mic"; from Simon Wilkinson;
     test + ok jakob.

1 files changed, 57 insertions, 11 deletions

diff --git a/auth2-gss.c b/auth2-gss.c
index 84fb384f9..220862dc8 100644
--- a/auth2-gss.c
+++ b/auth2-gss.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: auth2-gss.c,v 1.5 2003/11/02 11:01:03 markus Exp $    */
+/*      $OpenBSD: auth2-gss.c,v 1.6 2003/11/17 11:06:07 markus Exp $    */
 
 /*
  * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved.
@@ -43,6 +43,7 @@
 extern ServerOptions options;
 
 static void input_gssapi_token(int type, u_int32_t plen, void *ctxt);
+static void input_gssapi_mic(int type, u_int32_t plen, void *ctxt);
 static void input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt);
 static void input_gssapi_errtok(int, u_int32_t, void *);
 
@@ -129,7 +130,7 @@ input_gssapi_token(int type, u_int32_t plen, void *ctxt)
         Gssctxt *gssctxt;
         gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
         gss_buffer_desc recv_tok;
-        OM_uint32 maj_status, min_status;
+        OM_uint32 maj_status, min_status, flags;
         u_int len;
 
         if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep))
@@ -142,7 +143,7 @@ input_gssapi_token(int type, u_int32_t plen, void *ctxt)
         packet_check_eom();
 
         maj_status = PRIVSEP(ssh_gssapi_accept_ctx(gssctxt, &recv_tok,
-            &send_tok, NULL));
+            &send_tok, &flags));
 
         xfree(recv_tok.value);
 
@@ -154,7 +155,7 @@ input_gssapi_token(int type, u_int32_t plen, void *ctxt)
                 }
                 authctxt->postponed = 0;
                 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
-                userauth_finish(authctxt, 0, "gssapi");
+                userauth_finish(authctxt, 0, "gssapi-with-mic");
         } else {
                 if (send_tok.length != 0) {
                         packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
@@ -163,8 +164,13 @@ input_gssapi_token(int type, u_int32_t plen, void *ctxt)
                 }
                 if (maj_status == GSS_S_COMPLETE) {
                         dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
-                        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE,
-                                     &input_gssapi_exchange_complete);
+                        if (flags & GSS_C_INTEG_FLAG)
+                                dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_MIC,
+                                    &input_gssapi_mic);
+                        else
+                                dispatch_set(
+                                    SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE,
+                                    &input_gssapi_exchange_complete);
                 }
         }
 
@@ -224,9 +230,8 @@ input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt)
         gssctxt = authctxt->methoddata;
 
         /*
-         * We don't need to check the status, because the stored credentials
-         * which userok uses are only populated once the context init step
-         * has returned complete.
+         * We don't need to check the status, because we're only enabled in
+         * the dispatcher once the exchange is complete
          */
 
         packet_check_eom();
@@ -236,12 +241,53 @@ input_gssapi_exchange_complete(int type, u_int32_t plen, void *ctxt)
         authctxt->postponed = 0;
         dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
         dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, NULL);
+        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_MIC, NULL);
+        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL);
+        userauth_finish(authctxt, authenticated, "gssapi-with-mic");
+}
+
+static void
+input_gssapi_mic(int type, u_int32_t plen, void *ctxt)
+{
+        Authctxt *authctxt = ctxt;
+        Gssctxt *gssctxt;
+        int authenticated = 0;
+        Buffer b;
+        gss_buffer_desc mic, gssbuf;
+        u_int len;
+        
+        if (authctxt == NULL || (authctxt->methoddata == NULL && !use_privsep))
+                fatal("No authentication or GSSAPI context");
+        
+        gssctxt = authctxt->methoddata;
+        
+        mic.value = packet_get_string(&len);
+        mic.length = len;
+        
+        ssh_gssapi_buildmic(&b, authctxt->user, authctxt->service,
+            "gssapi-with-mic");
+        
+        gssbuf.value = buffer_ptr(&b);
+        gssbuf.length = buffer_len(&b);
+        
+        if (!GSS_ERROR(PRIVSEP(ssh_gssapi_checkmic(gssctxt, &gssbuf, &mic))))
+                authenticated = PRIVSEP(ssh_gssapi_userok(authctxt->user));
+        else
+                logit("GSSAPI MIC check failed");
+
+        buffer_free(&b);
+        xfree(mic.value);
+        
+        authctxt->postponed = 0;
+        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL);
+        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, NULL);
+        dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_MIC, NULL);
         dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL);
-        userauth_finish(authctxt, authenticated, "gssapi");
+        userauth_finish(authctxt, authenticated, "gssapi-with-mic");
 }
 
 Authmethod method_gssapi = {
-        "gssapi",
+        "gssapi-with-mic",
         userauth_gssapi,
         &options.gss_authentication
 };