cleanups to minimise merging hassle

[cyrus-sasl.git] / lib / server.c

diff --git a/lib/server.c b/lib/server.c
index 3013019..928447d 100644 (file)
--- a/lib/server.c
+++ b/lib/server.c
@@ -1453,7 +1453,39 @@ int sasl_server_step(sasl_conn_t *conn,
            conn->oparams.maxoutbuf = conn->props.maxbufsize;
        }
 
-       if(conn->oparams.user == NULL || conn->oparams.authid == NULL) {
+        /* Validate channel bindings */
+       switch (conn->oparams.cbindingdisp) {
+       case SASL_CB_DISP_NONE:
+           if (SASL_CB_CRITICAL(s_conn->sparams)) {
+               sasl_seterror(conn, 0,
+                             "server requires channel binding but client provided none");
+               ret = SASL_BADAUTH;
+           }
+           break;
+       case SASL_CB_DISP_WANT:
+           if (SASL_CB_PRESENT(s_conn->sparams)) {
+               sasl_seterror(conn, 0,
+                             "client incorrectly assumed server had no channel binding");
+               ret = SASL_BADAUTH;
+           }
+           break;
+       case SASL_CB_DISP_USED:
+           if (!SASL_CB_PRESENT(s_conn->sparams)) {
+               sasl_seterror(conn, 0,
+                             "client provided channel binding but server had none");
+               ret = SASL_BADAUTH;
+           } else if (strcmp(conn->oparams.cbindingname,
+                      s_conn->sparams->cbinding->name) != 0) {
+               sasl_seterror(conn, 0,
+                             "client channel binding %s does not match server %s",
+                             conn->oparams.cbindingname, s_conn->sparams->cbinding->name);
+               ret = SASL_BADAUTH;
+           }
+           break;
+       }
+
+        if (ret == SASL_OK &&
+           (conn->oparams.user == NULL || conn->oparams.authid == NULL)) {
            sasl_seterror(conn, 0,
                          "mech did not call canon_user for both authzid " \
                          "and authid");
@@ -1556,25 +1588,35 @@ int _sasl_server_listmech(sasl_conn_t *conn,
   for (lup = 0; lup < mechlist->mech_length; lup++) {
       /* currently, we don't use the "user" parameter for anything */
       if (mech_permitted(conn, listptr) == SASL_OK) {
-         if (pcount != NULL)
+          /*
+           * If the server would never succeed in the authentication of
+           * he non-PLUS-variant due to policy reasons, it MUST advertise
+           * only the PLUS-variant.
+           */
+          if (!SASL_CB_PRESENT(s_conn->sparams) ||
+              !SASL_CB_CRITICAL(s_conn->sparams)) {
+            if (pcount != NULL)
              (*pcount)++;
-
-         /* print separator */
-         if (flag) {
-             strcat(conn->mechlist_buf, mysep);
-         } else {
-             flag = 1;
-         }
-
-         /* now print the mechanism name */
-         strcat(conn->mechlist_buf, listptr->m.plug->mech_name);
-
-         /* advertise -PLUS variant if mechanism and application support CB */
+            if (flag)
+              strcat(conn->mechlist_buf, mysep);
+            else
+              flag = 1;
+           strcat(conn->mechlist_buf, listptr->m.plug->mech_name);
+          }
+          /*
+           * If the server cannot support channel binding, it SHOULD
+           * advertise only the non-PLUS-variant. Here, supporting channel
+           * binding means the underlying SASL mechanism supports it and
+           * the application has set some channel binding data.
+           */
          if ((listptr->m.plug->features & SASL_FEAT_CHANNEL_BINDING) &&
              SASL_CB_PRESENT(s_conn->sparams)) {
            if (pcount != NULL)
                (*pcount)++;
-           strcat(conn->mechlist_buf, mysep);
+            if (flag)
+              strcat(conn->mechlist_buf, mysep);
+            else
+              flag = 1;
            strcat(conn->mechlist_buf, listptr->m.plug->mech_name);
            strcat(conn->mechlist_buf, "-PLUS");
          }