This resolves a large number of compiler warnings from GCC 4.10 which cause the build to fail under dev mode. The vast majority are signed/unsigned mismatches in printf-style format strings. ........ Merged revisions 413586 from http://svn.asterisk.org/svn/asterisk/branches/1.8 ........ Merged revisions 413587 from http://svn.asterisk.org/svn/asterisk/branches/11 ........ Merged revisions 413588 from http://svn.asterisk.org/svn/asterisk/branches/12 git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@413589 65c4cc65-6c06-0410-ace0-fbb531ad65f3
874 lines
28 KiB
C
874 lines
28 KiB
C
/*
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* Asterisk -- An open source telephony toolkit.
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*
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* Copyright (C) 2012, Digium, Inc.
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*
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* Joshua Colp <jcolp@digium.com>
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*
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* See http://www.asterisk.org for more information about
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* the Asterisk project. Please do not directly contact
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* any of the maintainers of this project for assistance;
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* the project provides a web site, mailing lists and IRC
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* channels for your use.
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*
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* This program is free software, distributed under the terms of
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* the GNU General Public License Version 2. See the LICENSE file
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* at the top of the source tree.
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*/
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/*! \file
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*
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* \brief WebSocket support for the Asterisk internal HTTP server
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*
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* \author Joshua Colp <jcolp@digium.com>
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*/
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/*** MODULEINFO
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<support_level>extended</support_level>
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***/
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#include "asterisk.h"
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ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
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#include "asterisk/module.h"
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#include "asterisk/http.h"
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#include "asterisk/astobj2.h"
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#include "asterisk/strings.h"
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#include "asterisk/file.h"
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#include "asterisk/unaligned.h"
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#define AST_API_MODULE
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#include "asterisk/http_websocket.h"
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/*! \brief GUID used to compute the accept key, defined in the specifications */
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#define WEBSOCKET_GUID "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
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/*! \brief Number of buckets for registered protocols */
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#define MAX_PROTOCOL_BUCKETS 7
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/*! \brief Size of the pre-determined buffer for WebSocket frames */
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#define MAXIMUM_FRAME_SIZE 8192
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/*! \brief Default reconstruction size for multi-frame payload reconstruction. If exceeded the next frame will start a
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* payload.
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*/
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#define DEFAULT_RECONSTRUCTION_CEILING 16384
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/*! \brief Maximum reconstruction size for multi-frame payload reconstruction. */
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#define MAXIMUM_RECONSTRUCTION_CEILING 16384
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/*! \brief Maximum size of a websocket frame header
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* 1 byte flags and opcode
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* 1 byte mask flag + payload len
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* 8 bytes max extended length
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* 4 bytes optional masking key
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* ... payload follows ...
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* */
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#define MAX_WS_HDR_SZ 14
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#define MIN_WS_HDR_SZ 2
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/*! \brief Structure definition for session */
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struct ast_websocket {
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FILE *f; /*!< Pointer to the file instance used for writing and reading */
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int fd; /*!< File descriptor for the session, only used for polling */
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struct ast_sockaddr address; /*!< Address of the remote client */
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enum ast_websocket_opcode opcode; /*!< Cached opcode for multi-frame messages */
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size_t payload_len; /*!< Length of the payload */
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char *payload; /*!< Pointer to the payload */
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size_t reconstruct; /*!< Number of bytes before a reconstructed payload will be returned and a new one started */
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unsigned int secure:1; /*!< Bit to indicate that the transport is secure */
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unsigned int closing:1; /*!< Bit to indicate that the session is in the process of being closed */
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unsigned int close_sent:1; /*!< Bit to indicate that the session close opcode has been sent and no further data will be sent */
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};
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/*! \brief Structure definition for protocols */
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struct websocket_protocol {
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char *name; /*!< Name of the protocol */
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ast_websocket_callback callback; /*!< Callback called when a new session is established */
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};
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/*! \brief Hashing function for protocols */
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static int protocol_hash_fn(const void *obj, const int flags)
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{
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const struct websocket_protocol *protocol = obj;
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const char *name = obj;
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return ast_str_case_hash(flags & OBJ_KEY ? name : protocol->name);
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}
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/*! \brief Comparison function for protocols */
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static int protocol_cmp_fn(void *obj, void *arg, int flags)
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{
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const struct websocket_protocol *protocol1 = obj, *protocol2 = arg;
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const char *protocol = arg;
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return !strcasecmp(protocol1->name, flags & OBJ_KEY ? protocol : protocol2->name) ? CMP_MATCH | CMP_STOP : 0;
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}
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/*! \brief Destructor function for protocols */
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static void protocol_destroy_fn(void *obj)
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{
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struct websocket_protocol *protocol = obj;
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ast_free(protocol->name);
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}
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/*! \brief Structure for a WebSocket server */
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struct ast_websocket_server {
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struct ao2_container *protocols; /*!< Container for registered protocols */
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};
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static void websocket_server_internal_dtor(void *obj)
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{
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struct ast_websocket_server *server = obj;
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ao2_cleanup(server->protocols);
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server->protocols = NULL;
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}
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static void websocket_server_dtor(void *obj)
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{
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websocket_server_internal_dtor(obj);
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ast_module_unref(ast_module_info->self);
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}
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static struct ast_websocket_server *websocket_server_create_impl(void (*dtor)(void *))
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{
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RAII_VAR(struct ast_websocket_server *, server, NULL, ao2_cleanup);
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server = ao2_alloc(sizeof(*server), dtor);
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if (!server) {
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return NULL;
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}
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server->protocols = ao2_container_alloc(MAX_PROTOCOL_BUCKETS, protocol_hash_fn, protocol_cmp_fn);
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if (!server->protocols) {
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return NULL;
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}
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ao2_ref(server, +1);
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return server;
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}
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static struct ast_websocket_server *websocket_server_internal_create(void)
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{
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return websocket_server_create_impl(websocket_server_internal_dtor);
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}
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struct ast_websocket_server *AST_OPTIONAL_API_NAME(ast_websocket_server_create)(void)
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{
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ast_module_ref(ast_module_info->self);
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return websocket_server_create_impl(websocket_server_dtor);
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}
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/*! \brief Destructor function for sessions */
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static void session_destroy_fn(void *obj)
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{
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struct ast_websocket *session = obj;
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ast_websocket_close(session, 0);
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if (session->f) {
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fclose(session->f);
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ast_verb(2, "WebSocket connection from '%s' closed\n", ast_sockaddr_stringify(&session->address));
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}
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ast_free(session->payload);
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}
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int AST_OPTIONAL_API_NAME(ast_websocket_server_add_protocol)(struct ast_websocket_server *server, const char *name, ast_websocket_callback callback)
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{
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struct websocket_protocol *protocol;
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if (!server->protocols) {
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return -1;
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}
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ao2_lock(server->protocols);
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/* Ensure a second protocol handler is not registered for the same protocol */
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if ((protocol = ao2_find(server->protocols, name, OBJ_KEY | OBJ_NOLOCK))) {
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ao2_ref(protocol, -1);
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ao2_unlock(server->protocols);
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return -1;
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}
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if (!(protocol = ao2_alloc(sizeof(*protocol), protocol_destroy_fn))) {
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ao2_unlock(server->protocols);
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return -1;
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}
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if (!(protocol->name = ast_strdup(name))) {
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ao2_ref(protocol, -1);
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ao2_unlock(server->protocols);
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return -1;
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}
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protocol->callback = callback;
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ao2_link_flags(server->protocols, protocol, OBJ_NOLOCK);
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ao2_unlock(server->protocols);
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ao2_ref(protocol, -1);
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ast_verb(2, "WebSocket registered sub-protocol '%s'\n", name);
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return 0;
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}
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int AST_OPTIONAL_API_NAME(ast_websocket_server_remove_protocol)(struct ast_websocket_server *server, const char *name, ast_websocket_callback callback)
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{
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struct websocket_protocol *protocol;
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if (!(protocol = ao2_find(server->protocols, name, OBJ_KEY))) {
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return -1;
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}
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if (protocol->callback != callback) {
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ao2_ref(protocol, -1);
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return -1;
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}
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ao2_unlink(server->protocols, protocol);
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ao2_ref(protocol, -1);
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ast_verb(2, "WebSocket unregistered sub-protocol '%s'\n", name);
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return 0;
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}
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/*! \brief Close function for websocket session */
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int AST_OPTIONAL_API_NAME(ast_websocket_close)(struct ast_websocket *session, uint16_t reason)
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{
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char frame[4] = { 0, }; /* The header is 2 bytes and the reason code takes up another 2 bytes */
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int res;
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if (session->close_sent) {
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return 0;
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}
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frame[0] = AST_WEBSOCKET_OPCODE_CLOSE | 0x80;
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frame[1] = 2; /* The reason code is always 2 bytes */
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/* If no reason has been specified assume 1000 which is normal closure */
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put_unaligned_uint16(&frame[2], htons(reason ? reason : 1000));
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session->closing = 1;
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session->close_sent = 1;
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ao2_lock(session);
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res = (fwrite(frame, 1, 4, session->f) == 4) ? 0 : -1;
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ao2_unlock(session);
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return res;
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}
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/*! \brief Write function for websocket traffic */
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int AST_OPTIONAL_API_NAME(ast_websocket_write)(struct ast_websocket *session, enum ast_websocket_opcode opcode, char *payload, uint64_t actual_length)
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{
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size_t header_size = 2; /* The minimum size of a websocket frame is 2 bytes */
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char *frame;
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uint64_t length = 0;
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if (actual_length < 126) {
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length = actual_length;
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} else if (actual_length < (1 << 16)) {
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length = 126;
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/* We need an additional 2 bytes to store the extended length */
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header_size += 2;
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} else {
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length = 127;
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/* We need an additional 8 bytes to store the really really extended length */
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header_size += 8;
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}
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frame = ast_alloca(header_size);
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memset(frame, 0, sizeof(*frame));
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frame[0] = opcode | 0x80;
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frame[1] = length;
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/* Use the additional available bytes to store the length */
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if (length == 126) {
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put_unaligned_uint16(&frame[2], htons(actual_length));
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} else if (length == 127) {
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put_unaligned_uint64(&frame[2], htonl(actual_length));
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}
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ao2_lock(session);
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if (session->closing) {
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ao2_unlock(session);
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return -1;
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}
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if (fwrite(frame, 1, header_size, session->f) != header_size) {
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ao2_unlock(session);
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return -1;
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}
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if (fwrite(payload, 1, actual_length, session->f) != actual_length) {
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ao2_unlock(session);
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return -1;
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}
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fflush(session->f);
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ao2_unlock(session);
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return 0;
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}
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void AST_OPTIONAL_API_NAME(ast_websocket_reconstruct_enable)(struct ast_websocket *session, size_t bytes)
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{
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session->reconstruct = MIN(bytes, MAXIMUM_RECONSTRUCTION_CEILING);
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}
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void AST_OPTIONAL_API_NAME(ast_websocket_reconstruct_disable)(struct ast_websocket *session)
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{
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session->reconstruct = 0;
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}
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void AST_OPTIONAL_API_NAME(ast_websocket_ref)(struct ast_websocket *session)
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{
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ao2_ref(session, +1);
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}
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void AST_OPTIONAL_API_NAME(ast_websocket_unref)(struct ast_websocket *session)
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{
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ao2_cleanup(session);
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}
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int AST_OPTIONAL_API_NAME(ast_websocket_fd)(struct ast_websocket *session)
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{
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return session->closing ? -1 : session->fd;
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}
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struct ast_sockaddr * AST_OPTIONAL_API_NAME(ast_websocket_remote_address)(struct ast_websocket *session)
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{
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return &session->address;
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}
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int AST_OPTIONAL_API_NAME(ast_websocket_is_secure)(struct ast_websocket *session)
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{
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return session->secure;
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}
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int AST_OPTIONAL_API_NAME(ast_websocket_set_nonblock)(struct ast_websocket *session)
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{
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int flags;
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if ((flags = fcntl(session->fd, F_GETFL)) == -1) {
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return -1;
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}
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flags |= O_NONBLOCK;
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if ((flags = fcntl(session->fd, F_SETFL, flags)) == -1) {
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return -1;
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}
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return 0;
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}
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/* MAINTENANCE WARNING on ast_websocket_read()!
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*
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* We have to keep in mind during this function that the fact that session->fd seems ready
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* (via poll) does not necessarily mean we have application data ready, because in the case
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* of an SSL socket, there is some encryption data overhead that needs to be read from the
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* TCP socket, so poll() may say there are bytes to be read, but whether it is just 1 byte
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* or N bytes we do not know that, and we do not know how many of those bytes (if any) are
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* for application data (for us) and not just for the SSL protocol consumption
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*
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* There used to be a couple of nasty bugs here that were fixed in last refactoring but I
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* want to document them so the constraints are clear and we do not re-introduce them:
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*
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* - This function would incorrectly assume that fread() would necessarily return more than
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* 1 byte of data, just because a websocket frame is always >= 2 bytes, but the thing
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* is we're dealing with a TCP bitstream here, we could read just one byte and that's normal.
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* The problem before was that if just one byte was read, the function bailed out and returned
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* an error, effectively dropping the first byte of a websocket frame header!
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*
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* - Another subtle bug was that it would just read up to MAX_WS_HDR_SZ (14 bytes) via fread()
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* then assume that executing poll() would tell you if there is more to read, but since
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* we're dealing with a buffered stream (session->f is a FILE*), poll would say there is
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* nothing else to read (in the real tcp socket session->fd) and we would get stuck here
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* without processing the rest of the data in session->f internal buffers until another packet
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* came on the network to unblock us!
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*
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* Note during the header parsing stage we try to read in small chunks just what we need, this
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* is buffered data anyways, no expensive syscall required most of the time ...
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*/
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static inline int ws_safe_read(struct ast_websocket *session, char *buf, int len, enum ast_websocket_opcode *opcode)
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{
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int sanity;
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size_t rlen;
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int xlen = len;
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char *rbuf = buf;
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for (sanity = 10; sanity; sanity--) {
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clearerr(session->f);
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rlen = fread(rbuf, 1, xlen, session->f);
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if (0 == rlen && ferror(session->f) && errno != EAGAIN) {
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ast_log(LOG_ERROR, "Error reading from web socket: %s\n", strerror(errno));
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(*opcode) = AST_WEBSOCKET_OPCODE_CLOSE;
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session->closing = 1;
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return -1;
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}
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xlen = (xlen - rlen);
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rbuf = rbuf + rlen;
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if (0 == xlen) {
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break;
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}
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if (ast_wait_for_input(session->fd, 1000) < 0) {
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ast_log(LOG_ERROR, "ast_wait_for_input returned err: %s\n", strerror(errno));
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(*opcode) = AST_WEBSOCKET_OPCODE_CLOSE;
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session->closing = 1;
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return -1;
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}
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}
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if (!sanity) {
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ast_log(LOG_WARNING, "Websocket seems unresponsive, disconnecting ...\n");
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(*opcode) = AST_WEBSOCKET_OPCODE_CLOSE;
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session->closing = 1;
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return -1;
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}
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return 0;
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}
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int AST_OPTIONAL_API_NAME(ast_websocket_read)(struct ast_websocket *session, char **payload, uint64_t *payload_len, enum ast_websocket_opcode *opcode, int *fragmented)
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{
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char buf[MAXIMUM_FRAME_SIZE] = "";
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int fin = 0;
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int mask_present = 0;
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char *mask = NULL, *new_payload = NULL;
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size_t options_len = 0, frame_size = 0;
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*payload = NULL;
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*payload_len = 0;
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*fragmented = 0;
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if (ws_safe_read(session, &buf[0], MIN_WS_HDR_SZ, opcode)) {
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return 0;
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}
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frame_size += MIN_WS_HDR_SZ;
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/* ok, now we have the first 2 bytes, so we know some flags, opcode and payload length (or whether payload length extension will be required) */
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*opcode = buf[0] & 0xf;
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*payload_len = buf[1] & 0x7f;
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if (*opcode == AST_WEBSOCKET_OPCODE_TEXT || *opcode == AST_WEBSOCKET_OPCODE_BINARY || *opcode == AST_WEBSOCKET_OPCODE_CONTINUATION ||
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*opcode == AST_WEBSOCKET_OPCODE_PING || *opcode == AST_WEBSOCKET_OPCODE_PONG) {
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fin = (buf[0] >> 7) & 1;
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mask_present = (buf[1] >> 7) & 1;
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/* Based on the mask flag and payload length, determine how much more we need to read before start parsing the rest of the header */
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options_len += mask_present ? 4 : 0;
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options_len += (*payload_len == 126) ? 2 : (*payload_len == 127) ? 8 : 0;
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if (options_len) {
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/* read the rest of the header options */
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if (ws_safe_read(session, &buf[frame_size], options_len, opcode)) {
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return 0;
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}
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frame_size += options_len;
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}
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if (*payload_len == 126) {
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/* Grab the 2-byte payload length */
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*payload_len = ntohs(get_unaligned_uint16(&buf[2]));
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mask = &buf[4];
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} else if (*payload_len == 127) {
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/* Grab the 8-byte payload length */
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*payload_len = ntohl(get_unaligned_uint64(&buf[2]));
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mask = &buf[10];
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} else {
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/* Just set the mask after the small 2-byte header */
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mask = &buf[2];
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}
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/* Now read the rest of the payload */
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*payload = &buf[frame_size]; /* payload will start here, at the end of the options, if any */
|
|
frame_size = frame_size + (*payload_len); /* final frame size is header + optional headers + payload data */
|
|
if (frame_size > MAXIMUM_FRAME_SIZE) {
|
|
ast_log(LOG_WARNING, "Cannot fit huge websocket frame of %zu bytes\n", frame_size);
|
|
/* The frame won't fit :-( */
|
|
ast_websocket_close(session, 1009);
|
|
return -1;
|
|
}
|
|
|
|
if (ws_safe_read(session, (*payload), (*payload_len), opcode)) {
|
|
return 0;
|
|
}
|
|
|
|
/* If a mask is present unmask the payload */
|
|
if (mask_present) {
|
|
unsigned int pos;
|
|
for (pos = 0; pos < *payload_len; pos++) {
|
|
(*payload)[pos] ^= mask[pos % 4];
|
|
}
|
|
}
|
|
|
|
if (!(new_payload = ast_realloc(session->payload, (session->payload_len + *payload_len)))) {
|
|
ast_log(LOG_WARNING, "Failed allocation: %p, %zu, %"PRIu64"\n",
|
|
session->payload, session->payload_len, *payload_len);
|
|
*payload_len = 0;
|
|
ast_websocket_close(session, 1009);
|
|
return 0;
|
|
}
|
|
|
|
/* Per the RFC for PING we need to send back an opcode with the application data as received */
|
|
if (*opcode == AST_WEBSOCKET_OPCODE_PING) {
|
|
ast_websocket_write(session, AST_WEBSOCKET_OPCODE_PONG, *payload, *payload_len);
|
|
}
|
|
|
|
session->payload = new_payload;
|
|
memcpy((session->payload + session->payload_len), (*payload), (*payload_len));
|
|
session->payload_len += *payload_len;
|
|
|
|
if (!fin && session->reconstruct && (session->payload_len < session->reconstruct)) {
|
|
/* If this is not a final message we need to defer returning it until later */
|
|
if (*opcode != AST_WEBSOCKET_OPCODE_CONTINUATION) {
|
|
session->opcode = *opcode;
|
|
}
|
|
*opcode = AST_WEBSOCKET_OPCODE_CONTINUATION;
|
|
*payload_len = 0;
|
|
*payload = NULL;
|
|
} else {
|
|
if (*opcode == AST_WEBSOCKET_OPCODE_CONTINUATION) {
|
|
if (!fin) {
|
|
/* If this was not actually the final message tell the user it is fragmented so they can deal with it accordingly */
|
|
*fragmented = 1;
|
|
} else {
|
|
/* Final frame in multi-frame so push up the actual opcode */
|
|
*opcode = session->opcode;
|
|
}
|
|
}
|
|
*payload_len = session->payload_len;
|
|
*payload = session->payload;
|
|
session->payload_len = 0;
|
|
}
|
|
} else if (*opcode == AST_WEBSOCKET_OPCODE_CLOSE) {
|
|
/* Make the payload available so the user can look at the reason code if they so desire */
|
|
if ((*payload_len) && (new_payload = ast_realloc(session->payload, *payload_len))) {
|
|
if (ws_safe_read(session, &buf[frame_size], (*payload_len), opcode)) {
|
|
return 0;
|
|
}
|
|
session->payload = new_payload;
|
|
memcpy(session->payload, &buf[frame_size], *payload_len);
|
|
*payload = session->payload;
|
|
frame_size += (*payload_len);
|
|
}
|
|
|
|
session->closing = 1;
|
|
} else {
|
|
ast_log(LOG_WARNING, "WebSocket unknown opcode %u\n", *opcode);
|
|
/* We received an opcode that we don't understand, the RFC states that 1003 is for a type of data that can't be accepted... opcodes
|
|
* fit that, I think. */
|
|
ast_websocket_close(session, 1003);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*!
|
|
* \brief If the server has exactly one configured protocol, return it.
|
|
*/
|
|
static struct websocket_protocol *one_protocol(
|
|
struct ast_websocket_server *server)
|
|
{
|
|
SCOPED_AO2LOCK(lock, server->protocols);
|
|
|
|
if (ao2_container_count(server->protocols) != 1) {
|
|
return NULL;
|
|
}
|
|
|
|
return ao2_callback(server->protocols, OBJ_NOLOCK, NULL, NULL);
|
|
}
|
|
|
|
int AST_OPTIONAL_API_NAME(ast_websocket_uri_cb)(struct ast_tcptls_session_instance *ser, const struct ast_http_uri *urih, const char *uri, enum ast_http_method method, struct ast_variable *get_vars, struct ast_variable *headers)
|
|
{
|
|
struct ast_variable *v;
|
|
char *upgrade = NULL, *key = NULL, *key1 = NULL, *key2 = NULL, *protos = NULL, *requested_protocols = NULL, *protocol = NULL;
|
|
int version = 0, flags = 1;
|
|
struct websocket_protocol *protocol_handler = NULL;
|
|
struct ast_websocket *session;
|
|
struct ast_websocket_server *server;
|
|
|
|
SCOPED_MODULE_USE(ast_module_info->self);
|
|
|
|
/* Upgrade requests are only permitted on GET methods */
|
|
if (method != AST_HTTP_GET) {
|
|
ast_http_error(ser, 501, "Not Implemented", "Attempt to use unimplemented / unsupported method");
|
|
return -1;
|
|
}
|
|
|
|
server = urih->data;
|
|
|
|
/* Get the minimum headers required to satisfy our needs */
|
|
for (v = headers; v; v = v->next) {
|
|
if (!strcasecmp(v->name, "Upgrade")) {
|
|
upgrade = ast_strip(ast_strdupa(v->value));
|
|
} else if (!strcasecmp(v->name, "Sec-WebSocket-Key")) {
|
|
key = ast_strip(ast_strdupa(v->value));
|
|
} else if (!strcasecmp(v->name, "Sec-WebSocket-Key1")) {
|
|
key1 = ast_strip(ast_strdupa(v->value));
|
|
} else if (!strcasecmp(v->name, "Sec-WebSocket-Key2")) {
|
|
key2 = ast_strip(ast_strdupa(v->value));
|
|
} else if (!strcasecmp(v->name, "Sec-WebSocket-Protocol")) {
|
|
requested_protocols = ast_strip(ast_strdupa(v->value));
|
|
protos = ast_strdupa(requested_protocols);
|
|
} else if (!strcasecmp(v->name, "Sec-WebSocket-Version")) {
|
|
if (sscanf(v->value, "%30d", &version) != 1) {
|
|
version = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* If this is not a websocket upgrade abort */
|
|
if (!upgrade || strcasecmp(upgrade, "websocket")) {
|
|
ast_log(LOG_WARNING, "WebSocket connection from '%s' could not be accepted - did not request WebSocket\n",
|
|
ast_sockaddr_stringify(&ser->remote_address));
|
|
ast_http_error(ser, 426, "Upgrade Required", NULL);
|
|
return -1;
|
|
} else if (ast_strlen_zero(requested_protocols)) {
|
|
/* If there's only a single protocol registered, and the
|
|
* client doesn't specify what protocol it's using, go ahead
|
|
* and accept the connection */
|
|
protocol_handler = one_protocol(server);
|
|
if (!protocol_handler) {
|
|
/* Multiple registered subprotocols; client must specify */
|
|
ast_log(LOG_WARNING, "WebSocket connection from '%s' could not be accepted - no protocols requested\n",
|
|
ast_sockaddr_stringify(&ser->remote_address));
|
|
fputs("HTTP/1.1 400 Bad Request\r\n"
|
|
"Sec-WebSocket-Version: 7, 8, 13\r\n\r\n", ser->f);
|
|
return -1;
|
|
}
|
|
} else if (key1 && key2) {
|
|
/* Specification defined in http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-76 and
|
|
* http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-00 -- not currently supported*/
|
|
ast_log(LOG_WARNING, "WebSocket connection from '%s' could not be accepted - unsupported version '00/76' chosen\n",
|
|
ast_sockaddr_stringify(&ser->remote_address));
|
|
fputs("HTTP/1.1 400 Bad Request\r\n"
|
|
"Sec-WebSocket-Version: 7, 8, 13\r\n\r\n", ser->f);
|
|
return 0;
|
|
}
|
|
|
|
/* Iterate through the requested protocols trying to find one that we have a handler for */
|
|
while (!protocol_handler && (protocol = strsep(&requested_protocols, ","))) {
|
|
protocol_handler = ao2_find(server->protocols, ast_strip(protocol), OBJ_KEY);
|
|
}
|
|
|
|
/* If no protocol handler exists bump this back to the requester */
|
|
if (!protocol_handler) {
|
|
ast_log(LOG_WARNING, "WebSocket connection from '%s' could not be accepted - no protocols out of '%s' supported\n",
|
|
ast_sockaddr_stringify(&ser->remote_address), protos);
|
|
fputs("HTTP/1.1 400 Bad Request\r\n"
|
|
"Sec-WebSocket-Version: 7, 8, 13\r\n\r\n", ser->f);
|
|
return 0;
|
|
}
|
|
|
|
/* Determine how to respond depending on the version */
|
|
if (version == 7 || version == 8 || version == 13) {
|
|
/* Version 7 defined in specification http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-07 */
|
|
/* Version 8 defined in specification http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-10 */
|
|
/* Version 13 defined in specification http://tools.ietf.org/html/rfc6455 */
|
|
char *combined, base64[64];
|
|
unsigned combined_length;
|
|
uint8_t sha[20];
|
|
|
|
combined_length = (key ? strlen(key) : 0) + strlen(WEBSOCKET_GUID) + 1;
|
|
if (!key || combined_length > 8192) { /* no stack overflows please */
|
|
fputs("HTTP/1.1 400 Bad Request\r\n"
|
|
"Sec-WebSocket-Version: 7, 8, 13\r\n\r\n", ser->f);
|
|
ao2_ref(protocol_handler, -1);
|
|
return 0;
|
|
}
|
|
|
|
if (!(session = ao2_alloc(sizeof(*session), session_destroy_fn))) {
|
|
ast_log(LOG_WARNING, "WebSocket connection from '%s' could not be accepted\n",
|
|
ast_sockaddr_stringify(&ser->remote_address));
|
|
fputs("HTTP/1.1 400 Bad Request\r\n"
|
|
"Sec-WebSocket-Version: 7, 8, 13\r\n\r\n", ser->f);
|
|
ao2_ref(protocol_handler, -1);
|
|
return 0;
|
|
}
|
|
|
|
combined = ast_alloca(combined_length);
|
|
snprintf(combined, combined_length, "%s%s", key, WEBSOCKET_GUID);
|
|
ast_sha1_hash_uint(sha, combined);
|
|
ast_base64encode(base64, (const unsigned char*)sha, 20, sizeof(base64));
|
|
|
|
fprintf(ser->f, "HTTP/1.1 101 Switching Protocols\r\n"
|
|
"Upgrade: %s\r\n"
|
|
"Connection: Upgrade\r\n"
|
|
"Sec-WebSocket-Accept: %s\r\n",
|
|
upgrade,
|
|
base64);
|
|
|
|
/* RFC 6455, Section 4.1:
|
|
*
|
|
* 6. If the response includes a |Sec-WebSocket-Protocol| header
|
|
* field and this header field indicates the use of a
|
|
* subprotocol that was not present in the client's handshake
|
|
* (the server has indicated a subprotocol not requested by
|
|
* the client), the client MUST _Fail the WebSocket
|
|
* Connection_.
|
|
*/
|
|
if (protocol) {
|
|
fprintf(ser->f, "Sec-WebSocket-Protocol: %s\r\n",
|
|
protocol);
|
|
}
|
|
|
|
fprintf(ser->f, "\r\n");
|
|
fflush(ser->f);
|
|
} else {
|
|
|
|
/* Specification defined in http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-75 or completely unknown */
|
|
ast_log(LOG_WARNING, "WebSocket connection from '%s' could not be accepted - unsupported version '%d' chosen\n",
|
|
ast_sockaddr_stringify(&ser->remote_address), version ? version : 75);
|
|
fputs("HTTP/1.1 400 Bad Request\r\n"
|
|
"Sec-WebSocket-Version: 7, 8, 13\r\n\r\n", ser->f);
|
|
ao2_ref(protocol_handler, -1);
|
|
return 0;
|
|
}
|
|
|
|
/* Enable keepalive on all sessions so the underlying user does not have to */
|
|
if (setsockopt(ser->fd, SOL_SOCKET, SO_KEEPALIVE, &flags, sizeof(flags))) {
|
|
ast_log(LOG_WARNING, "WebSocket connection from '%s' could not be accepted - failed to enable keepalive\n",
|
|
ast_sockaddr_stringify(&ser->remote_address));
|
|
fputs("HTTP/1.1 400 Bad Request\r\n"
|
|
"Sec-WebSocket-Version: 7, 8, 13\r\n\r\n", ser->f);
|
|
ao2_ref(session, -1);
|
|
ao2_ref(protocol_handler, -1);
|
|
return 0;
|
|
}
|
|
|
|
ast_verb(2, "WebSocket connection from '%s' for protocol '%s' accepted using version '%d'\n", ast_sockaddr_stringify(&ser->remote_address), protocol ? : "", version);
|
|
|
|
/* Populate the session with all the needed details */
|
|
session->f = ser->f;
|
|
session->fd = ser->fd;
|
|
ast_sockaddr_copy(&session->address, &ser->remote_address);
|
|
session->opcode = -1;
|
|
session->reconstruct = DEFAULT_RECONSTRUCTION_CEILING;
|
|
session->secure = ser->ssl ? 1 : 0;
|
|
|
|
/* Give up ownership of the socket and pass it to the protocol handler */
|
|
protocol_handler->callback(session, get_vars, headers);
|
|
ao2_ref(protocol_handler, -1);
|
|
|
|
/* By dropping the FILE* from the session it won't get closed when the HTTP server cleans up */
|
|
ser->f = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct ast_http_uri websocketuri = {
|
|
.callback = AST_OPTIONAL_API_NAME(ast_websocket_uri_cb),
|
|
.description = "Asterisk HTTP WebSocket",
|
|
.uri = "ws",
|
|
.has_subtree = 0,
|
|
.data = NULL,
|
|
.key = __FILE__,
|
|
};
|
|
|
|
/*! \brief Simple echo implementation which echoes received text and binary frames */
|
|
static void websocket_echo_callback(struct ast_websocket *session, struct ast_variable *parameters, struct ast_variable *headers)
|
|
{
|
|
int flags, res;
|
|
|
|
ast_debug(1, "Entering WebSocket echo loop\n");
|
|
|
|
if ((flags = fcntl(ast_websocket_fd(session), F_GETFL)) == -1) {
|
|
goto end;
|
|
}
|
|
|
|
flags |= O_NONBLOCK;
|
|
|
|
if (fcntl(ast_websocket_fd(session), F_SETFL, flags) == -1) {
|
|
goto end;
|
|
}
|
|
|
|
while ((res = ast_wait_for_input(ast_websocket_fd(session), -1)) > 0) {
|
|
char *payload;
|
|
uint64_t payload_len;
|
|
enum ast_websocket_opcode opcode;
|
|
int fragmented;
|
|
|
|
if (ast_websocket_read(session, &payload, &payload_len, &opcode, &fragmented)) {
|
|
/* We err on the side of caution and terminate the session if any error occurs */
|
|
ast_log(LOG_WARNING, "Read failure during WebSocket echo loop\n");
|
|
break;
|
|
}
|
|
|
|
if (opcode == AST_WEBSOCKET_OPCODE_TEXT || opcode == AST_WEBSOCKET_OPCODE_BINARY) {
|
|
ast_websocket_write(session, opcode, payload, payload_len);
|
|
} else if (opcode == AST_WEBSOCKET_OPCODE_CLOSE) {
|
|
break;
|
|
} else {
|
|
ast_debug(1, "Ignored WebSocket opcode %u\n", opcode);
|
|
}
|
|
}
|
|
|
|
end:
|
|
ast_debug(1, "Exitting WebSocket echo loop\n");
|
|
ast_websocket_unref(session);
|
|
}
|
|
|
|
static int websocket_add_protocol_internal(const char *name, ast_websocket_callback callback)
|
|
{
|
|
struct ast_websocket_server *ws_server = websocketuri.data;
|
|
if (!ws_server) {
|
|
return -1;
|
|
}
|
|
return ast_websocket_server_add_protocol(ws_server, name, callback);
|
|
}
|
|
|
|
int AST_OPTIONAL_API_NAME(ast_websocket_add_protocol)(const char *name, ast_websocket_callback callback)
|
|
{
|
|
int res = websocket_add_protocol_internal(name, callback);
|
|
if (res == 0) {
|
|
ast_module_ref(ast_module_info->self);
|
|
}
|
|
return res;
|
|
}
|
|
|
|
static int websocket_remove_protocol_internal(const char *name, ast_websocket_callback callback)
|
|
{
|
|
struct ast_websocket_server *ws_server = websocketuri.data;
|
|
if (!ws_server) {
|
|
return -1;
|
|
}
|
|
return ast_websocket_server_remove_protocol(ws_server, name, callback);
|
|
}
|
|
|
|
int AST_OPTIONAL_API_NAME(ast_websocket_remove_protocol)(const char *name, ast_websocket_callback callback)
|
|
{
|
|
int res = websocket_remove_protocol_internal(name, callback);
|
|
if (res == 0) {
|
|
ast_module_unref(ast_module_info->self);
|
|
}
|
|
return res;
|
|
}
|
|
|
|
static int load_module(void)
|
|
{
|
|
websocketuri.data = websocket_server_internal_create();
|
|
if (!websocketuri.data) {
|
|
return AST_MODULE_LOAD_FAILURE;
|
|
}
|
|
ast_http_uri_link(&websocketuri);
|
|
websocket_add_protocol_internal("echo", websocket_echo_callback);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int unload_module(void)
|
|
{
|
|
ast_websocket_remove_protocol("echo", websocket_echo_callback);
|
|
ast_http_uri_unlink(&websocketuri);
|
|
ao2_ref(websocketuri.data, -1);
|
|
websocketuri.data = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "HTTP WebSocket Support",
|
|
.load = load_module,
|
|
.unload = unload_module,
|
|
.load_pri = AST_MODPRI_CHANNEL_DEPEND,
|
|
);
|