Peer-id patch v2

index ef2bde1..0f1a36f 100644
@@ -223,6 +223,30 @@ err:
   return;
 }
 
+int verify_hmac(struct buffer *buf, struct key_ctx *ctx, int offset)
+{
+  uint8_t local_hmac[MAX_HMAC_KEY_LENGTH]; /* HMAC of ciphertext computed locally */
+  int hmac_len = 0;
+
+  hmac_ctx_reset(ctx->hmac);
+  /* Assume the length of the input HMAC */
+  hmac_len = hmac_ctx_size (ctx->hmac);
+
+  /* Authentication fails if insufficient data in packet for HMAC */
+  if (buf->len - offset < hmac_len)
+    return 0;
+
+  hmac_ctx_update (ctx->hmac, BPTR (buf) + hmac_len + offset,
+  	BLEN (buf) - hmac_len - offset);
+  hmac_ctx_final (ctx->hmac, local_hmac);
+
+  /* Compare locally computed HMAC with packet HMAC */
+  if (memcmp_constant_time (local_hmac, BPTR (buf) + offset, hmac_len) == 0)
+    return hmac_len;
+
+  return 0;
+}
+
 /*
  * If (opt->flags & CO_USE_IV) is not NULL, we will read an IV from the packet.
  *

@@ -249,25 +273,9 @@ openvpn_decrypt (struct buffer *buf, struct buffer work,
       /* Verify the HMAC */
       if (ctx->hmac)
 	{
-	  int hmac_len;
-	  uint8_t local_hmac[MAX_HMAC_KEY_LENGTH]; /* HMAC of ciphertext computed locally */
-
-	  hmac_ctx_reset(ctx->hmac);
-
-	  /* Assume the length of the input HMAC */
-	  hmac_len = hmac_ctx_size (ctx->hmac);
-
-	  /* Authentication fails if insufficient data in packet for HMAC */
-	  if (buf->len < hmac_len)
-	    CRYPT_ERROR ("missing authentication info");
-
-	  hmac_ctx_update (ctx->hmac, BPTR (buf) + hmac_len, BLEN (buf) - hmac_len);
-	  hmac_ctx_final (ctx->hmac, local_hmac);
-
-	  /* Compare locally computed HMAC with packet HMAC */
-	  if (memcmp_constant_time (local_hmac, BPTR (buf), hmac_len))
+	  int hmac_len = verify_hmac(buf, ctx, 0);
+	  if (hmac_len == 0)
 	    CRYPT_ERROR ("packet HMAC authentication failed");
-
 	  ASSERT (buf_advance (buf, hmac_len));
 	}
 

@@ -392,6 +400,28 @@ openvpn_decrypt (struct buffer *buf, struct buffer work,
 }
 
 /*
+ * This verifies if a packet and its HMAC fit to a crypto context.
+ *
+ * On success true is returned.
+ */
+bool
+crypto_test_hmac (struct buffer *buf, const struct crypto_options *opt)
+{
+  if (buf->len > 0 && opt->key_ctx_bi)
+    {
+      struct key_ctx *ctx = &opt->key_ctx_bi->decrypt;
+
+      /* Verify the HMAC */
+      if (ctx->hmac)
+	{
+	  /* sizeof(uint32_t) comes from peer_id (3 bytes) and opcode (1 byte) */
+	  return verify_hmac(buf, ctx, sizeof(uint32_t)) != 0;
+	}
+    }
+  return false;
+}
+
+/*
  * How many bytes will we add to frame buffer for a given
  * set of crypto options?
  */

index bf2f802..3c4e59d 100644
@@ -275,6 +275,9 @@ bool openvpn_decrypt (struct buffer *buf, struct buffer work,
 		      const struct crypto_options *opt,
 		      const struct frame* frame);
 
+
+bool crypto_test_hmac (struct buffer *buf, const struct crypto_options *opt);
+
 /** @} name Functions for performing security operations on data channel packets */
 
 void crypto_adjust_frame_parameters(struct frame *frame,

index a673be5..3811e09 100644
@@ -1718,7 +1718,8 @@ pull_permission_mask (const struct context *c)
     | OPT_P_MESSAGES
     | OPT_P_EXPLICIT_NOTIFY
     | OPT_P_ECHO
-    | OPT_P_PULL_MODE;
+    | OPT_P_PULL_MODE
+    | OPT_P_PEER_ID;
 
   if (!c->options.route_nopull)
     flags |= (OPT_P_ROUTE | OPT_P_IPWIN32);

@@ -1795,6 +1796,13 @@ do_deferred_options (struct context *c, const unsigned int found)
     msg (D_PUSH, "OPTIONS IMPORT: --ip-win32 and/or --dhcp-option options modified");
   if (found & OPT_P_SETENV)
     msg (D_PUSH, "OPTIONS IMPORT: environment modified");
+
+  if (found & OPT_P_PEER_ID)
+    {
+      msg (D_PUSH, "OPTIONS IMPORT: peer-id set");
+      c->c2.tls_multi->use_peer_id = true;
+      c->c2.tls_multi->peer_id = c->options.peer_id;
+    }
 }
 
 /*

140 lines not on this page · raw message

index dc96854..dcc1be4 100644
@@ -373,6 +373,8 @@ multi_init (struct multi_context *m, struct context *t, bool tcp_mode, int threa
    */
   m->max_clients = t->options.max_clients;
 
+  m->instances = calloc(m->max_clients, sizeof(struct multi_instance*));
+
   /*
    * Initialize multi-socket TCP I/O wait object
    */

@@ -553,6 +555,8 @@ multi_close_instance (struct multi_context *m,
 	}
 #endif
 
+      m->instances[mi->context.c2.tls_multi->peer_id] = NULL;
+
       schedule_remove_entry (m->schedule, (struct schedule_entry *) mi);
 
       ifconfig_pool_release (m->ifconfig_pool, mi->vaddr_handle, false);

@@ -629,6 +633,8 @@ multi_uninit (struct multi_context *m)
 #endif
 	  m->hash = NULL;
 
+	  free(m->instances);
+
 	  schedule_free (m->schedule);
 	  mbuf_free (m->mbuf);
 	  ifconfig_pool_free (m->ifconfig_pool);

index fc2ffb2..0446fbf 100644
@@ -125,6 +125,8 @@ struct multi_context {
 # define MC_WORK_THREAD                (MC_MULTI_THREADED_WORKER|MC_MULTI_THREADED_SCHEDULER)
   int thread_mode;
 
+  struct multi_instance** instances;
+
   struct hash *hash;            /**< VPN tunnel instances indexed by real
                                  *   address of the remote peer. */
   struct hash *vhash;           /**< VPN tunnel instances indexed by

index 84eb6ed..67a93e1 100644
@@ -3906,7 +3906,8 @@ apply_push_options (struct options *options,
 		    struct buffer *buf,
 		    unsigned int permission_mask,
 		    unsigned int *option_types_found,
-		    struct env_set *es)
+		    struct env_set *es,
+		    struct tls_multi *tls_multi)
 {
   char line[OPTION_PARM_SIZE];
   int line_num = 0;

@@ -6985,6 +6986,12 @@ add_option (struct options *options,
       options->persist_mode = 1;
     }
 #endif
+  else if (streq (p[0], "peer-id"))
+    {
+      VERIFY_PERMISSION (OPT_P_PEER_ID);
+      options->use_peer_id = true;
+      options->peer_id = atoi(p[1]);
+    }
   else
     {
       int i;

index 5ba4f2f..2b9666e 100644
@@ -598,6 +598,9 @@ struct options
   bool show_net_up;
   int route_method;
 #endif
+
+  bool use_peer_id;
+  uint32_t peer_id;
 };
 
 #define streq(x, y) (!strcmp((x), (y)))

@@ -633,6 +636,7 @@ struct options
 #define OPT_P_SOCKBUF         (1<<25)
 #define OPT_P_SOCKFLAGS       (1<<26)
 #define OPT_P_CONNECTION      (1<<27)
+#define OPT_P_PEER_ID         (1<<28)
 
 #define OPT_P_DEFAULT   (~(OPT_P_INSTANCE|OPT_P_PULL_MODE))
 

@@ -719,11 +723,13 @@ void options_postprocess (struct options *options);
 void pre_pull_save (struct options *o);
 void pre_pull_restore (struct options *o, struct gc_arena *gc);
 
+struct tls_multi;
 bool apply_push_options (struct options *options,
 			 struct buffer *buf,
 			 unsigned int permission_mask,
 			 unsigned int *option_types_found,
-			 struct env_set *es);
+			 struct env_set *es,
+			 struct tls_multi* tls_multi);
 
 void options_detach (struct options *o);
 

index 1de9f74..6e4bec9 100644
@@ -305,6 +305,19 @@ send_push_reply (struct context *c)
   if (multi_push)
     buf_printf (&buf, ",push-continuation 1");
 
+  /* Send peer-id if client supports it */
+  if (c->c2.tls_multi->peer_info)
+    {
+      const char* proto_str = strstr(c->c2.tls_multi->peer_info, "IV_PROTO=");
+      if (proto_str)
+	{
+	  int proto = 0;
+	  int r = sscanf(proto_str, "IV_PROTO=%d", &proto);
+	  if ((r == 1) && (proto >= 2))
+	    buf_printf(&buf, ",peer-id %d", c->c2.tls_multi->peer_id);
+	}
+  }
+
   if (BLEN (&buf) > sizeof(cmd)-1)
     {
       const bool status = send_control_channel_string (c, BSTR (&buf), D_PUSH);

@@ -464,7 +477,8 @@ process_incoming_push_msg (struct context *c,
 				  &buf,
 				  permission_mask,
 				  option_types_found,
-				  c->c2.es))
+				  c->c2.es,
+				  c->c2.tls_multi))
 	    switch (c->options.push_continuation)
 	      {
 	      case 0:

121 lines not on this page · raw message

index aaecff4..a338745 100644
@@ -60,6 +60,7 @@
 #define P_CONTROL_V1                   4     /* control channel packet (usually TLS ciphertext) */
 #define P_ACK_V1                       5     /* acknowledgement for packets received */
 #define P_DATA_V1                      6     /* data channel packet */
+#define P_DATA_V2                      9     /* data channel packet with peer-id */
 
 /* indicates key_method >= 2 */
 #define P_CONTROL_HARD_RESET_CLIENT_V2 7     /* initial key from client, forget previous state */

@@ -67,7 +68,7 @@
 
 /* define the range of legal opcodes */
 #define P_FIRST_OPCODE                 1
-#define P_LAST_OPCODE                  8
+#define P_LAST_OPCODE                  9
 
 /* Should we aggregate TLS
  * acknowledgements, and tack them onto

@@ -430,6 +431,12 @@ bool tls_send_payload (struct tls_multi *multi,
 bool tls_rec_payload (struct tls_multi *multi,
 		      struct buffer *buf);
 
+/*
+ * Update remote address of a tls_multi structure
+ */
+void tls_update_remote_addr (struct tls_multi *multi,
+			     const struct link_socket_actual *from);
+
 #ifdef MANAGEMENT_DEF_AUTH
 static inline char *
 tls_get_peer_info(const struct tls_multi *multi)

index 04ba789..cb0ba62 100644
@@ -495,6 +495,10 @@ struct tls_multi
   char *peer_info;
 #endif
 
+  /* For P_DATA_V2 */
+  uint32_t peer_id;
+  bool use_peer_id;
+
   /*
    * Our session objects.
    */