asterisk/res/res_ari_events.c
Matt Jordan 9cffcca5f9 res/ari: Register Stasis application on WebSocket attempt
Prior to this patch, when a WebSocket connection is made, ARI would not
be informed of the connection until after the WebSocket layer had
accepted the connection. This created a brief race condition where the
ARI client would be notified that it was connected, a channel would be
sent into the Stasis dialplan application, but ARI would not yet have
registered the Stasis application presented in the HTTP request that
established the WebSocket.

This patch resolves this issue by doing the following:
 * When a WebSocket attempt is made, a callback is made into the ARI
   application layer, which verifies and registers the apps presented in
   the HTTP request. Because we do not yet have a WebSocket, we cannot
   have an event session for the corresponding applications. Some
   defensive checks were thus added to make the application objects
   tolerant to a NULL event session.
 * When a WebSocket connection is made, the registered application is
   updated with the newly created event session that wraps the WebSocket
   connection.

ASTERISK-24988 #close
Reported by: Joshua Colp

Change-Id: Ia5dc60dc2b6bee76cd5aff0f69dd53b36e83f636
2015-05-22 11:13:34 -05:00

470 lines
12 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2012 - 2013, Digium, Inc.
*
* David M. Lee, II <dlee@digium.com>
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
/*
* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
* !!!!! DO NOT EDIT !!!!!
* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
* This file is generated by a mustache template. Please see the original
* template in rest-api-templates/res_ari_resource.c.mustache
*/
/*! \file
*
* \brief WebSocket resource
*
* \author David M. Lee, II <dlee@digium.com>
*/
/*** MODULEINFO
<depend type="module">res_ari</depend>
<depend type="module">res_ari_model</depend>
<depend type="module">res_stasis</depend>
<support_level>core</support_level>
***/
#include "asterisk.h"
ASTERISK_REGISTER_FILE()
#include "asterisk/app.h"
#include "asterisk/module.h"
#include "asterisk/stasis_app.h"
#include "ari/resource_events.h"
#if defined(AST_DEVMODE)
#include "ari/ari_model_validators.h"
#endif
#include "asterisk/http_websocket.h"
#define MAX_VALS 128
static int ast_ari_events_event_websocket_ws_attempted_cb(struct ast_tcptls_session_instance *ser, struct ast_variable *get_params, struct ast_variable *headers)
{
struct ast_ari_events_event_websocket_args args = {};
int res = 0;
RAII_VAR(struct ast_ari_response *, response, NULL, ast_free);
struct ast_variable *i;
response = ast_calloc(1, sizeof(*response));
if (!response) {
ast_log(LOG_ERROR, "Failed to create response.\n");
goto fin;
}
for (i = get_params; i; i = i->next) {
if (strcmp(i->name, "app") == 0) {
/* Parse comma separated list */
char *vals[MAX_VALS];
size_t j;
args.app_parse = ast_strdup(i->value);
if (!args.app_parse) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (strlen(args.app_parse) == 0) {
/* ast_app_separate_args can't handle "" */
args.app_count = 1;
vals[0] = args.app_parse;
} else {
args.app_count = ast_app_separate_args(
args.app_parse, ',', vals,
ARRAY_LEN(vals));
}
if (args.app_count == 0) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (args.app_count >= MAX_VALS) {
ast_ari_response_error(response, 400,
"Bad Request",
"Too many values for app");
goto fin;
}
args.app = ast_malloc(sizeof(*args.app) * args.app_count);
if (!args.app) {
ast_ari_response_alloc_failed(response);
goto fin;
}
for (j = 0; j < args.app_count; ++j) {
args.app[j] = (vals[j]);
}
} else
{}
}
res = ast_ari_websocket_events_event_websocket_attempted(ser, headers, &args);
fin: __attribute__((unused))
if (!response) {
ast_http_error(ser, 500, "Server Error", "Memory allocation error");
res = -1;
} else if (response->response_code != 0) {
/* Param parsing failure */
RAII_VAR(char *, msg, NULL, ast_json_free);
if (response->message) {
msg = ast_json_dump_string(response->message);
} else {
ast_log(LOG_ERROR, "Missing response message\n");
}
if (msg) {
ast_http_error(ser, response->response_code, response->response_text, msg);
}
res = -1;
}
ast_free(args.app_parse);
ast_free(args.app);
return res;
}
static void ast_ari_events_event_websocket_ws_established_cb(struct ast_websocket *ws_session,
struct ast_variable *get_params, struct ast_variable *headers)
{
struct ast_ari_events_event_websocket_args args = {};
RAII_VAR(struct ast_ari_response *, response, NULL, ast_free);
struct ast_variable *i;
RAII_VAR(struct ast_websocket *, s, ws_session, ast_websocket_unref);
RAII_VAR(struct ast_ari_websocket_session *, session, NULL, ao2_cleanup);
response = ast_calloc(1, sizeof(*response));
if (!response) {
ast_log(LOG_ERROR, "Failed to create response.\n");
goto fin;
}
#if defined(AST_DEVMODE)
session = ast_ari_websocket_session_create(ws_session,
ast_ari_validate_message_fn());
#else
session = ast_ari_websocket_session_create(ws_session, NULL);
#endif
if (!session) {
ast_log(LOG_ERROR, "Failed to create ARI session\n");
goto fin;
}
for (i = get_params; i; i = i->next) {
if (strcmp(i->name, "app") == 0) {
/* Parse comma separated list */
char *vals[MAX_VALS];
size_t j;
args.app_parse = ast_strdup(i->value);
if (!args.app_parse) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (strlen(args.app_parse) == 0) {
/* ast_app_separate_args can't handle "" */
args.app_count = 1;
vals[0] = args.app_parse;
} else {
args.app_count = ast_app_separate_args(
args.app_parse, ',', vals,
ARRAY_LEN(vals));
}
if (args.app_count == 0) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (args.app_count >= MAX_VALS) {
ast_ari_response_error(response, 400,
"Bad Request",
"Too many values for app");
goto fin;
}
args.app = ast_malloc(sizeof(*args.app) * args.app_count);
if (!args.app) {
ast_ari_response_alloc_failed(response);
goto fin;
}
for (j = 0; j < args.app_count; ++j) {
args.app[j] = (vals[j]);
}
} else
{}
}
ast_ari_websocket_events_event_websocket_established(session, headers, &args);
fin: __attribute__((unused))
if (response && response->response_code != 0) {
/* Param parsing failure */
RAII_VAR(char *, msg, NULL, ast_json_free);
if (response->message) {
msg = ast_json_dump_string(response->message);
} else {
ast_log(LOG_ERROR, "Missing response message\n");
}
if (msg) {
ast_websocket_write(ws_session,
AST_WEBSOCKET_OPCODE_TEXT, msg, strlen(msg));
}
}
ast_free(args.app_parse);
ast_free(args.app);
}
int ast_ari_events_user_event_parse_body(
struct ast_json *body,
struct ast_ari_events_user_event_args *args)
{
struct ast_json *field;
/* Parse query parameters out of it */
field = ast_json_object_get(body, "application");
if (field) {
args->application = ast_json_string_get(field);
}
field = ast_json_object_get(body, "source");
if (field) {
/* If they were silly enough to both pass in a query param and a
* JSON body, free up the query value.
*/
ast_free(args->source);
if (ast_json_typeof(field) == AST_JSON_ARRAY) {
/* Multiple param passed as array */
size_t i;
args->source_count = ast_json_array_size(field);
args->source = ast_malloc(sizeof(*args->source) * args->source_count);
if (!args->source) {
return -1;
}
for (i = 0; i < args->source_count; ++i) {
args->source[i] = ast_json_string_get(ast_json_array_get(field, i));
}
} else {
/* Multiple param passed as single value */
args->source_count = 1;
args->source = ast_malloc(sizeof(*args->source) * args->source_count);
if (!args->source) {
return -1;
}
args->source[0] = ast_json_string_get(field);
}
}
return 0;
}
/*!
* \brief Parameter parsing callback for /events/user/{eventName}.
* \param get_params GET parameters in the HTTP request.
* \param path_vars Path variables extracted from the request.
* \param headers HTTP headers.
* \param[out] response Response to the HTTP request.
*/
static void ast_ari_events_user_event_cb(
struct ast_tcptls_session_instance *ser,
struct ast_variable *get_params, struct ast_variable *path_vars,
struct ast_variable *headers, struct ast_ari_response *response)
{
struct ast_ari_events_user_event_args args = {};
struct ast_variable *i;
RAII_VAR(struct ast_json *, body, NULL, ast_json_unref);
#if defined(AST_DEVMODE)
int is_valid;
int code;
#endif /* AST_DEVMODE */
for (i = get_params; i; i = i->next) {
if (strcmp(i->name, "application") == 0) {
args.application = (i->value);
} else
if (strcmp(i->name, "source") == 0) {
/* Parse comma separated list */
char *vals[MAX_VALS];
size_t j;
args.source_parse = ast_strdup(i->value);
if (!args.source_parse) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (strlen(args.source_parse) == 0) {
/* ast_app_separate_args can't handle "" */
args.source_count = 1;
vals[0] = args.source_parse;
} else {
args.source_count = ast_app_separate_args(
args.source_parse, ',', vals,
ARRAY_LEN(vals));
}
if (args.source_count == 0) {
ast_ari_response_alloc_failed(response);
goto fin;
}
if (args.source_count >= MAX_VALS) {
ast_ari_response_error(response, 400,
"Bad Request",
"Too many values for source");
goto fin;
}
args.source = ast_malloc(sizeof(*args.source) * args.source_count);
if (!args.source) {
ast_ari_response_alloc_failed(response);
goto fin;
}
for (j = 0; j < args.source_count; ++j) {
args.source[j] = (vals[j]);
}
} else
{}
}
for (i = path_vars; i; i = i->next) {
if (strcmp(i->name, "eventName") == 0) {
args.event_name = (i->value);
} else
{}
}
/* Look for a JSON request entity */
body = ast_http_get_json(ser, headers);
if (!body) {
switch (errno) {
case EFBIG:
ast_ari_response_error(response, 413, "Request Entity Too Large", "Request body too large");
goto fin;
case ENOMEM:
ast_ari_response_error(response, 500, "Internal Server Error", "Error processing request");
goto fin;
case EIO:
ast_ari_response_error(response, 400, "Bad Request", "Error parsing request body");
goto fin;
}
}
args.variables = body;
ast_ari_events_user_event(headers, &args, response);
#if defined(AST_DEVMODE)
code = response->response_code;
switch (code) {
case 0: /* Implementation is still a stub, or the code wasn't set */
is_valid = response->message == NULL;
break;
case 500: /* Internal Server Error */
case 501: /* Not Implemented */
case 404: /* Application does not exist. */
case 422: /* Event source not found. */
case 400: /* Invalid even tsource URI or userevent data. */
is_valid = 1;
break;
default:
if (200 <= code && code <= 299) {
is_valid = ast_ari_validate_void(
response->message);
} else {
ast_log(LOG_ERROR, "Invalid error response %d for /events/user/{eventName}\n", code);
is_valid = 0;
}
}
if (!is_valid) {
ast_log(LOG_ERROR, "Response validation failed for /events/user/{eventName}\n");
ast_ari_response_error(response, 500,
"Internal Server Error", "Response validation failed");
}
#endif /* AST_DEVMODE */
fin: __attribute__((unused))
ast_free(args.source_parse);
ast_free(args.source);
return;
}
/*! \brief REST handler for /api-docs/events.{format} */
static struct stasis_rest_handlers events_user_eventName = {
.path_segment = "eventName",
.is_wildcard = 1,
.callbacks = {
[AST_HTTP_POST] = ast_ari_events_user_event_cb,
},
.num_children = 0,
.children = { }
};
/*! \brief REST handler for /api-docs/events.{format} */
static struct stasis_rest_handlers events_user = {
.path_segment = "user",
.callbacks = {
},
.num_children = 1,
.children = { &events_user_eventName, }
};
/*! \brief REST handler for /api-docs/events.{format} */
static struct stasis_rest_handlers events = {
.path_segment = "events",
.callbacks = {
},
.num_children = 1,
.children = { &events_user, }
};
static int load_module(void)
{
int res = 0;
struct ast_websocket_protocol *protocol;
events.ws_server = ast_websocket_server_create();
if (!events.ws_server) {
return AST_MODULE_LOAD_FAILURE;
}
protocol = ast_websocket_sub_protocol_alloc("ari");
if (!protocol) {
ao2_ref(events.ws_server, -1);
events.ws_server = NULL;
return AST_MODULE_LOAD_FAILURE;
}
protocol->session_attempted = ast_ari_events_event_websocket_ws_attempted_cb;
protocol->session_established = ast_ari_events_event_websocket_ws_established_cb;
res |= ast_websocket_server_add_protocol2(events.ws_server, protocol);
stasis_app_ref();
res |= ast_ari_add_handler(&events);
return res;
}
static int unload_module(void)
{
ast_ari_remove_handler(&events);
ao2_cleanup(events.ws_server);
events.ws_server = NULL;
stasis_app_unref();
return 0;
}
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "RESTful API module - WebSocket resource",
.support_level = AST_MODULE_SUPPORT_CORE,
.load = load_module,
.unload = unload_module,
.nonoptreq = "res_ari,res_stasis",
);