auth/spnego: split gensec_spnego_create_negTokenInit() into subfunctions
[vlendec/samba-autobuild/.git] / auth / gensec / spnego.c
index aae3cabe97b75536eb0c6b42fea7eca3e0adc996..d2fbdd5afc0553551e4d56f84896c9ac5e97ad09 100644 (file)
@@ -47,6 +47,74 @@ enum spnego_state_position {
        SPNEGO_DONE
 };
 
+struct spnego_state;
+struct spnego_neg_ops;
+struct spnego_neg_state;
+
+struct spnego_neg_state {
+       const struct spnego_neg_ops *ops;
+       const struct gensec_security_ops_wrapper *all_sec;
+       size_t all_idx;
+       const char * const *mech_types;
+       size_t mech_idx;
+};
+
+struct spnego_neg_ops {
+       const char *name;
+       /*
+        * The start hook does the initial processing on the incoming paket and
+        * may starts the first possible subcontext. It indicates that
+        * gensec_update() is required on the subcontext by returning
+        * NT_STATUS_MORE_PROCESSING_REQUIRED and return something useful in
+        * 'in_next'. Note that 'in_mem_ctx' is just passed as a hint, the
+        * caller should treat 'in_next' as const and don't attempt to free the
+        * content.  NT_STATUS_OK indicates the finish hook should be invoked
+        * directly withing the need of gensec_update() on the subcontext.
+        * Every other error indicates an error that's returned to the caller.
+        */
+       NTSTATUS (*start_fn)(struct gensec_security *gensec_security,
+                            struct spnego_state *spnego_state,
+                            struct spnego_neg_state *n,
+                            struct spnego_data *spnego_in,
+                            TALLOC_CTX *in_mem_ctx,
+                            DATA_BLOB *in_next);
+       /*
+        * The step hook processes the result of a failed gensec_update() and
+        * can decide to ignore a failure and continue the negotiation by
+        * setting up the next possible subcontext. It indicates that
+        * gensec_update() is required on the subcontext by returning
+        * NT_STATUS_MORE_PROCESSING_REQUIRED and return something useful in
+        * 'in_next'. Note that 'in_mem_ctx' is just passed as a hint, the
+        * caller should treat 'in_next' as const and don't attempt to free the
+        * content.  NT_STATUS_OK indicates the finish hook should be invoked
+        * directly withing the need of gensec_update() on the subcontext.
+        * Every other error indicates an error that's returned to the caller.
+        */
+       NTSTATUS (*step_fn)(struct gensec_security *gensec_security,
+                           struct spnego_state *spnego_state,
+                           struct spnego_neg_state *n,
+                           struct spnego_data *spnego_in,
+                           NTSTATUS last_status,
+                           TALLOC_CTX *in_mem_ctx,
+                           DATA_BLOB *in_next);
+       /*
+        * The finish hook processes the result of a successful gensec_update()
+        * (NT_STATUS_OK or NT_STATUS_MORE_PROCESSING_REQUIRED). It forms the
+        * response pdu that will be returned from the toplevel gensec_update()
+        * together with NT_STATUS_OK or NT_STATUS_MORE_PROCESSING_REQUIRED. It
+        * may also alter the state machine to prepare receiving the next pdu
+        * from the peer.
+        */
+       NTSTATUS (*finish_fn)(struct gensec_security *gensec_security,
+                             struct spnego_state *spnego_state,
+                             struct spnego_neg_state *n,
+                             struct spnego_data *spnego_in,
+                             NTSTATUS sub_status,
+                             const DATA_BLOB sub_out,
+                             TALLOC_CTX *out_mem_ctx,
+                             DATA_BLOB *out);
+};
+
 struct spnego_state {
        enum spnego_message_type expected_packet;
        enum spnego_state_position state_position;
@@ -77,6 +145,74 @@ struct spnego_state {
        NTSTATUS out_status;
 };
 
+static struct spnego_neg_state *gensec_spnego_neg_state(TALLOC_CTX *mem_ctx,
+               const struct spnego_neg_ops *ops)
+{
+       struct spnego_neg_state *n = NULL;
+
+       n = talloc_zero(mem_ctx, struct spnego_neg_state);
+       if (n == NULL) {
+               return NULL;
+       }
+       n->ops = ops;
+
+       return n;
+}
+
+static NTSTATUS gensec_spnego_neg_loop(struct gensec_security *gensec_security,
+                                      struct spnego_state *spnego_state,
+                                      const const struct spnego_neg_ops *ops,
+                                      struct tevent_context *ev,
+                                      struct spnego_data *spnego_in,
+                                      TALLOC_CTX *out_mem_ctx,
+                                      DATA_BLOB *out)
+{
+       struct spnego_neg_state *n = NULL;
+       NTSTATUS status;
+       DATA_BLOB sub_in = data_blob_null;
+       DATA_BLOB sub_out = data_blob_null;
+
+       *out = data_blob_null;
+
+       n = gensec_spnego_neg_state(out_mem_ctx, ops);
+       if (n == NULL) {
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       status = n->ops->start_fn(gensec_security, spnego_state, n,
+                                 spnego_in, n, &sub_in);
+       if (GENSEC_UPDATE_IS_NTERROR(status)) {
+               TALLOC_FREE(n);
+               return status;
+       }
+
+       while (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
+               status = gensec_update_ev(spnego_state->sub_sec_security,
+                                         n, ev, sub_in, &sub_out);
+               sub_in = data_blob_null;
+               if (NT_STATUS_IS_OK(status)) {
+                       spnego_state->sub_sec_ready = true;
+               }
+               if (!GENSEC_UPDATE_IS_NTERROR(status)) {
+                       break;
+               }
+               sub_out = data_blob_null;
+
+               status = n->ops->step_fn(gensec_security, spnego_state, n,
+                                        spnego_in, status, n, &sub_in);
+               if (GENSEC_UPDATE_IS_NTERROR(status)) {
+                       TALLOC_FREE(n);
+                       return status;
+               }
+       }
+
+       status = n->ops->finish_fn(gensec_security, spnego_state, n,
+                                  spnego_in, status, sub_out,
+                                  out_mem_ctx, out);
+       TALLOC_FREE(n);
+       return status;
+}
+
 static void gensec_spnego_update_sub_abort(struct spnego_state *spnego_state)
 {
        spnego_state->sub_sec_ready = false;
@@ -203,86 +339,59 @@ static NTSTATUS gensec_spnego_server_try_fallback(struct gensec_security *gensec
        return NT_STATUS_INVALID_PARAMETER;
 }
 
-/** create a negTokenInit 
- *
- * This is the same packet, no matter if the client or server sends it first, but it is always the first packet
-*/
-static NTSTATUS gensec_spnego_create_negTokenInit(struct gensec_security *gensec_security, 
-                                                 struct spnego_state *spnego_state,
-                                                 TALLOC_CTX *out_mem_ctx, 
-                                                 struct tevent_context *ev,
-                                                 DATA_BLOB *out)
+static NTSTATUS gensec_spnego_create_negTokenInit_start(
+                                       struct gensec_security *gensec_security,
+                                       struct spnego_state *spnego_state,
+                                       struct spnego_neg_state *n,
+                                       struct spnego_data *spnego_in,
+                                       TALLOC_CTX *in_mem_ctx,
+                                       DATA_BLOB *in_next)
 {
-       NTSTATUS status;
-       const char **mechTypes = NULL;
-       DATA_BLOB unwrapped_out = data_blob_null;
-       size_t all_idx = 0;
-       const struct gensec_security_ops_wrapper *all_sec;
-       const struct gensec_security_ops_wrapper *cur_sec = NULL;
-       const char **send_mech_types = NULL;
-       struct spnego_data spnego_out;
-       bool ok;
-
-       mechTypes = gensec_security_oids(gensec_security, 
-                                        out_mem_ctx, GENSEC_OID_SPNEGO);
-       if (mechTypes == NULL) {
+       n->mech_idx = 0;
+       n->mech_types = gensec_security_oids(gensec_security, n,
+                                            GENSEC_OID_SPNEGO);
+       if (n->mech_types == NULL) {
                DBG_WARNING("gensec_security_oids() failed\n");
                return NT_STATUS_NO_MEMORY;
        }
 
-       all_sec = gensec_security_by_oid_list(gensec_security, 
-                                             out_mem_ctx, 
-                                             mechTypes,
-                                             GENSEC_OID_SPNEGO);
-       if (all_sec == NULL) {
+       n->all_idx = 0;
+       n->all_sec = gensec_security_by_oid_list(gensec_security,
+                                                n, n->mech_types,
+                                                GENSEC_OID_SPNEGO);
+       if (n->all_sec == NULL) {
                DBG_WARNING("gensec_security_by_oid_list() failed\n");
                return NT_STATUS_NO_MEMORY;
        }
 
-       for (; all_sec[all_idx].op != NULL; all_idx++) {
+       return n->ops->step_fn(gensec_security, spnego_state, n,
+                              spnego_in, NT_STATUS_OK, in_mem_ctx, in_next);
+}
+
+static NTSTATUS gensec_spnego_create_negTokenInit_step(
+                                       struct gensec_security *gensec_security,
+                                       struct spnego_state *spnego_state,
+                                       struct spnego_neg_state *n,
+                                       struct spnego_data *spnego_in,
+                                       NTSTATUS last_status,
+                                       TALLOC_CTX *in_mem_ctx,
+                                       DATA_BLOB *in_next)
+{
+       if (!NT_STATUS_IS_OK(last_status)) {
+               const struct gensec_security_ops_wrapper *cur_sec =
+                       &n->all_sec[n->all_idx];
+               const struct gensec_security_ops_wrapper *next_sec = NULL;
                const char *next = NULL;
                const char *principal = NULL;
                int dbg_level = DBGLVL_WARNING;
+               NTSTATUS status = last_status;
 
-               cur_sec = &all_sec[all_idx];
-
-               status = gensec_subcontext_start(spnego_state,
-                                                gensec_security,
-                                                &spnego_state->sub_sec_security);
-               if (!NT_STATUS_IS_OK(status)) {
-                       return status;
-               }
-               /* select the sub context */
-               status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
-                                                 cur_sec->op);
-               if (!NT_STATUS_IS_OK(status)) {
-                       gensec_spnego_update_sub_abort(spnego_state);
-                       continue;
-               }
-
-               if (spnego_state->state_position != SPNEGO_CLIENT_START) {
-                       /*
-                        * The server doesn't generate an optimistic token.
-                        */
-                       goto reply;
-               }
-
-               /* In the client, try and produce the first (optimistic) packet */
-               status = gensec_update_ev(spnego_state->sub_sec_security,
-                                         out_mem_ctx,
-                                         ev,
-                                         data_blob_null,
-                                         &unwrapped_out);
-               if (NT_STATUS_IS_OK(status)) {
-                       spnego_state->sub_sec_ready = true;
-               }
-
-               if (!GENSEC_UPDATE_IS_NTERROR(status)) {
-                       goto reply;
+               if (cur_sec[1].op != NULL) {
+                       next_sec = &cur_sec[1];
                }
 
-               if (cur_sec[1].op != NULL) {
-                       next = cur_sec[1].op->name;
+               if (next_sec != NULL) {
+                       next = next_sec->op->name;
                        dbg_level = DBGLVL_NOTICE;
                }
 
@@ -315,23 +424,72 @@ static NTSTATUS gensec_spnego_create_negTokenInit(struct gensec_security *gensec
                 * Pretend we never started it
                 */
                gensec_spnego_update_sub_abort(spnego_state);
+
+               /*
+                * And try the next one...
+                */
+               n->all_idx += 1;
+       }
+
+       for (; n->all_sec[n->all_idx].op != NULL; n->all_idx++) {
+               const struct gensec_security_ops_wrapper *cur_sec =
+                       &n->all_sec[n->all_idx];
+               NTSTATUS status;
+
+               status = gensec_subcontext_start(spnego_state,
+                                                gensec_security,
+                                                &spnego_state->sub_sec_security);
+               if (!NT_STATUS_IS_OK(status)) {
+                       return status;
+               }
+
+               /* select the sub context */
+               status = gensec_start_mech_by_ops(spnego_state->sub_sec_security,
+                                                 cur_sec->op);
+               if (!NT_STATUS_IS_OK(status)) {
+                       gensec_spnego_update_sub_abort(spnego_state);
+                       continue;
+               }
+
+               /* In the client, try and produce the first (optimistic) packet */
+               if (spnego_state->state_position == SPNEGO_CLIENT_START) {
+                       *in_next = data_blob_null;
+                       return NT_STATUS_MORE_PROCESSING_REQUIRED;
+               }
+
+               *in_next = data_blob_null;
+               return NT_STATUS_OK;
        }
 
        DBG_WARNING("Failed to setup SPNEGO negTokenInit request\n");
        return NT_STATUS_INVALID_PARAMETER;
+}
+
+static NTSTATUS gensec_spnego_create_negTokenInit_finish(
+                                       struct gensec_security *gensec_security,
+                                       struct spnego_state *spnego_state,
+                                       struct spnego_neg_state *n,
+                                       struct spnego_data *spnego_in,
+                                       NTSTATUS sub_status,
+                                       const DATA_BLOB sub_out,
+                                       TALLOC_CTX *out_mem_ctx,
+                                       DATA_BLOB *out)
+{
+       const struct gensec_security_ops_wrapper *cur_sec =
+                       &n->all_sec[n->all_idx];
+       struct spnego_data spnego_out;
+       bool ok;
 
-reply:
        spnego_out.type = SPNEGO_NEG_TOKEN_INIT;
 
-       send_mech_types = gensec_security_oids_from_ops_wrapped(out_mem_ctx,
-                                                               cur_sec);
-       if (send_mech_types == NULL) {
+       n->mech_types = gensec_security_oids_from_ops_wrapped(n, cur_sec);
+       if (n->mech_types == NULL) {
                DBG_WARNING("gensec_security_oids_from_ops_wrapped() failed\n");
                return NT_STATUS_NO_MEMORY;
        }
 
        ok = spnego_write_mech_types(spnego_state,
-                                    send_mech_types,
+                                    n->mech_types,
                                     &spnego_state->mech_types);
        if (!ok) {
                DBG_ERR("Failed to write mechTypes\n");
@@ -339,7 +497,7 @@ reply:
        }
 
        /* List the remaining mechs as options */
-       spnego_out.negTokenInit.mechTypes = send_mech_types;
+       spnego_out.negTokenInit.mechTypes = n->mech_types;
        spnego_out.negTokenInit.reqFlags = data_blob_null;
        spnego_out.negTokenInit.reqFlagsPadding = 0;
 
@@ -350,7 +508,7 @@ reply:
                spnego_out.negTokenInit.mechListMIC = data_blob_null;
        }
 
-       spnego_out.negTokenInit.mechToken = unwrapped_out;
+       spnego_out.negTokenInit.mechToken = sub_out;
 
        if (spnego_write_data(out_mem_ctx, out, &spnego_out) == -1) {
                DBG_ERR("Failed to write NEG_TOKEN_INIT\n");
@@ -376,6 +534,29 @@ reply:
        return NT_STATUS_MORE_PROCESSING_REQUIRED;
 }
 
+static const struct spnego_neg_ops gensec_spnego_create_negTokenInit_ops = {
+       .name      = "create_negTokenInit",
+       .start_fn  = gensec_spnego_create_negTokenInit_start,
+       .step_fn   = gensec_spnego_create_negTokenInit_step,
+       .finish_fn = gensec_spnego_create_negTokenInit_finish,
+};
+
+/** create a negTokenInit
+ *
+ * This is the same packet, no matter if the client or server sends it first, but it is always the first packet
+*/
+static NTSTATUS gensec_spnego_create_negTokenInit(struct gensec_security *gensec_security,
+                                                 struct spnego_state *spnego_state,
+                                                 TALLOC_CTX *out_mem_ctx,
+                                                 struct tevent_context *ev,
+                                                 DATA_BLOB *out)
+{
+       struct spnego_data *spnego_in = NULL;
+       return gensec_spnego_neg_loop(gensec_security, spnego_state,
+                                     &gensec_spnego_create_negTokenInit_ops,
+                                     ev, spnego_in, out_mem_ctx, out);
+}
+
 static NTSTATUS gensec_spnego_client_negTokenInit(struct gensec_security *gensec_security,
                                                  struct spnego_state *spnego_state,
                                                  struct tevent_context *ev,