asterisk/res/res_ari.c

1215 lines
36 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.
*/
/*! \file
*
* \brief HTTP binding for the Stasis API
* \author David M. Lee, II <dlee@digium.com>
*
* The API itself is documented using <a
* href="https://developers.helloreverb.com/swagger/">Swagger</a>, a lightweight
* mechanism for documenting RESTful API's using JSON. This allows us to use <a
* href="https://github.com/wordnik/swagger-ui">swagger-ui</a> to provide
* executable documentation for the API, generate client bindings in different
* <a href="https://github.com/asterisk/asterisk_rest_libraries">languages</a>,
* and generate a lot of the boilerplate code for implementing the RESTful
* bindings. The API docs live in the \c rest-api/ directory.
*
* The RESTful bindings are generated from the Swagger API docs using a set of
* <a href="http://mustache.github.io/mustache.5.html">Mustache</a> templates.
* The code generator is written in Python, and uses the Python implementation
* <a href="https://github.com/defunkt/pystache">pystache</a>. Pystache has no
* dependencies, and be installed easily using \c pip. Code generation code
* lives in \c rest-api-templates/.
*
* The generated code reduces a lot of boilerplate when it comes to handling
* HTTP requests. It also helps us have greater consistency in the REST API.
*
* The structure of the generated code is:
*
* - res/ari/resource_{resource}.h
* - For each operation in the resource, a generated argument structure
* (holding the parsed arguments from the request) and function
* declarations (to implement in res/ari/resource_{resource}.c)
* - res_ari_{resource}.c
* - A set of \ref stasis_rest_callback functions, which glue the two
* together. They parse out path variables and request parameters to
* populate a specific \c *_args which is passed to the specific request
* handler (in res/ari/resource_{resource}.c)
* - A tree of \ref stasis_rest_handlers for routing requests to its
* \ref stasis_rest_callback
*
* The basic flow of an HTTP request is:
*
* - ast_ari_callback()
* 1. Initial request validation
* 2. Routes as either a doc request (ast_ari_get_docs) or API
* request (ast_ari_invoke)
* - ast_ari_invoke()
* 1. Further request validation
* 2. Routes the request through the tree of generated
* \ref stasis_rest_handlers.
* 3. Dispatch to the generated callback
* - \c ast_ari_*_cb
* 1. Populate \c *_args struct with path and get params
* 2. Invoke the request handler
* 3. Validates and sends response
*/
/*** MODULEINFO
<depend type="module">res_http_websocket</depend>
<depend type="module">res_stasis</depend>
<support_level>core</support_level>
***/
/*** DOCUMENTATION
<configInfo name="res_ari" language="en_US">
<synopsis>HTTP binding for the Stasis API</synopsis>
<configFile name="ari.conf">
<configObject name="general">
<synopsis>General configuration settings</synopsis>
<configOption name="enabled">
<synopsis>Enable/disable the ARI module</synopsis>
<description>
<para>This option enables or disables the ARI module.</para>
<note>
<para>ARI uses Asterisk's HTTP server, which must also be enabled in <filename>http.conf</filename>.</para>
</note>
</description>
<see-also>
<ref type="filename">http.conf</ref>
<ref type="link">https://wiki.asterisk.org/wiki/display/AST/Asterisk+Builtin+mini-HTTP+Server</ref>
</see-also>
</configOption>
<configOption name="websocket_write_timeout" default="100">
<synopsis>The timeout (in milliseconds) to set on WebSocket connections.</synopsis>
<description>
<para>If a websocket connection accepts input slowly, the timeout
for writes to it can be increased to keep it from being disconnected.
Value is in milliseconds.</para>
</description>
</configOption>
<configOption name="pretty">
<synopsis>Responses from ARI are formatted to be human readable</synopsis>
</configOption>
<configOption name="auth_realm">
<synopsis>Realm to use for authentication. Defaults to Asterisk REST Interface.</synopsis>
</configOption>
<configOption name="allowed_origins">
<synopsis>Comma separated list of allowed origins, for Cross-Origin Resource Sharing. May be set to * to allow all origins.</synopsis>
</configOption>
<configOption name="channelvars">
<synopsis>Comma separated list of channel variables to display in channel json.</synopsis>
</configOption>
</configObject>
<configObject name="user">
<synopsis>Per-user configuration settings</synopsis>
<configOption name="type">
<synopsis>Define this configuration section as a user.</synopsis>
<description>
<enumlist>
<enum name="user"><para>Configure this section as a <replaceable>user</replaceable></para></enum>
</enumlist>
</description>
</configOption>
<configOption name="read_only">
<synopsis>When set to yes, user is only authorized for read-only requests</synopsis>
</configOption>
<configOption name="password">
<synopsis>Crypted or plaintext password (see password_format)</synopsis>
</configOption>
<configOption name="password_format">
<synopsis>password_format may be set to plain (the default) or crypt. When set to crypt, crypt(3) is used to validate the password. A crypted password can be generated using mkpasswd -m sha-512. When set to plain, the password is in plaintext</synopsis>
</configOption>
</configObject>
</configFile>
</configInfo>
***/
#include "asterisk.h"
#include "ari/internal.h"
#include "asterisk/ari.h"
#include "asterisk/astobj2.h"
#include "asterisk/module.h"
#include "asterisk/paths.h"
#include "asterisk/stasis_app.h"
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
/*! \brief Helper function to check if module is enabled. */
static int is_enabled(void)
{
RAII_VAR(struct ast_ari_conf *, cfg, ast_ari_config_get(), ao2_cleanup);
return cfg && cfg->general && cfg->general->enabled;
}
/*! Lock for \ref root_handler */
static ast_mutex_t root_handler_lock;
/*! Handler for root RESTful resource. */
static struct stasis_rest_handlers *root_handler;
/*! Pre-defined message for allocation failures. */
static struct ast_json *oom_json;
struct ast_json *ast_ari_oom_json(void)
{
return oom_json;
}
int ast_ari_add_handler(struct stasis_rest_handlers *handler)
{
RAII_VAR(struct stasis_rest_handlers *, new_handler, NULL, ao2_cleanup);
size_t old_size, new_size;
SCOPED_MUTEX(lock, &root_handler_lock);
old_size = sizeof(*new_handler) + root_handler->num_children * sizeof(handler);
new_size = old_size + sizeof(handler);
new_handler = ao2_alloc(new_size, NULL);
if (!new_handler) {
return -1;
}
memcpy(new_handler, root_handler, old_size);
new_handler->children[new_handler->num_children++] = handler;
ao2_cleanup(root_handler);
ao2_ref(new_handler, +1);
root_handler = new_handler;
return 0;
}
int ast_ari_remove_handler(struct stasis_rest_handlers *handler)
{
struct stasis_rest_handlers *new_handler;
size_t size;
size_t i;
size_t j;
ast_assert(root_handler != NULL);
ast_mutex_lock(&root_handler_lock);
size = sizeof(*new_handler) + root_handler->num_children * sizeof(handler);
new_handler = ao2_alloc(size, NULL);
if (!new_handler) {
ast_mutex_unlock(&root_handler_lock);
return -1;
}
/* Create replacement root_handler less the handler to remove. */
memcpy(new_handler, root_handler, sizeof(*new_handler));
for (i = 0, j = 0; i < root_handler->num_children; ++i) {
if (root_handler->children[i] == handler) {
continue;
}
new_handler->children[j++] = root_handler->children[i];
}
new_handler->num_children = j;
/* Replace the old root_handler with the new. */
ao2_cleanup(root_handler);
root_handler = new_handler;
ast_mutex_unlock(&root_handler_lock);
return 0;
}
static struct stasis_rest_handlers *get_root_handler(void)
{
SCOPED_MUTEX(lock, &root_handler_lock);
ao2_ref(root_handler, +1);
return root_handler;
}
static struct stasis_rest_handlers *root_handler_create(void)
{
RAII_VAR(struct stasis_rest_handlers *, handler, NULL, ao2_cleanup);
handler = ao2_alloc(sizeof(*handler), NULL);
if (!handler) {
return NULL;
}
handler->path_segment = "ari";
ao2_ref(handler, +1);
return handler;
}
void ast_ari_response_error(struct ast_ari_response *response,
int response_code,
const char *response_text,
const char *message_fmt, ...)
{
RAII_VAR(struct ast_json *, message, NULL, ast_json_unref);
va_list ap;
va_start(ap, message_fmt);
message = ast_json_vstringf(message_fmt, ap);
va_end(ap);
response->message = ast_json_pack("{s: o}",
"message", ast_json_ref(message));
response->response_code = response_code;
response->response_text = response_text;
}
void ast_ari_response_ok(struct ast_ari_response *response,
struct ast_json *message)
{
response->message = message;
response->response_code = 200;
response->response_text = "OK";
}
void ast_ari_response_no_content(struct ast_ari_response *response)
{
response->message = ast_json_null();
response->response_code = 204;
response->response_text = "No Content";
}
void ast_ari_response_accepted(struct ast_ari_response *response)
{
response->message = ast_json_null();
response->response_code = 202;
response->response_text = "Accepted";
}
void ast_ari_response_alloc_failed(struct ast_ari_response *response)
{
response->message = ast_json_ref(oom_json);
response->response_code = 500;
response->response_text = "Internal Server Error";
}
void ast_ari_response_created(struct ast_ari_response *response,
const char *url, struct ast_json *message)
{
RAII_VAR(struct stasis_rest_handlers *, root, get_root_handler(), ao2_cleanup);
response->message = message;
response->response_code = 201;
response->response_text = "Created";
ast_str_append(&response->headers, 0, "Location: /%s%s\r\n", root->path_segment, url);
}
static void add_allow_header(struct stasis_rest_handlers *handler,
struct ast_ari_response *response)
{
enum ast_http_method m;
ast_str_append(&response->headers, 0,
"Allow: OPTIONS");
for (m = 0; m < AST_HTTP_MAX_METHOD; ++m) {
if (handler->callbacks[m] != NULL) {
ast_str_append(&response->headers, 0,
",%s", ast_get_http_method(m));
}
}
ast_str_append(&response->headers, 0, "\r\n");
}
static int origin_allowed(const char *origin)
{
RAII_VAR(struct ast_ari_conf *, cfg, ast_ari_config_get(), ao2_cleanup);
char *allowed = ast_strdupa(cfg->general->allowed_origins);
char *current;
while ((current = strsep(&allowed, ","))) {
if (!strcmp(current, "*")) {
return 1;
}
if (!strcmp(current, origin)) {
return 1;
}
}
return 0;
}
#define ACR_METHOD "Access-Control-Request-Method"
#define ACR_HEADERS "Access-Control-Request-Headers"
#define ACA_METHODS "Access-Control-Allow-Methods"
#define ACA_HEADERS "Access-Control-Allow-Headers"
/*!
* \brief Handle OPTIONS request, mainly for CORS preflight requests.
*
* Some browsers will send this prior to non-simple methods (i.e. DELETE).
* See http://www.w3.org/TR/cors/ for the spec. Especially section 6.2.
*/
static void handle_options(struct stasis_rest_handlers *handler,
struct ast_variable *headers,
struct ast_ari_response *response)
{
struct ast_variable *header;
char const *acr_method = NULL;
char const *acr_headers = NULL;
char const *origin = NULL;
RAII_VAR(struct ast_str *, allow, NULL, ast_free);
enum ast_http_method m;
int allowed = 0;
/* Regular OPTIONS response */
add_allow_header(handler, response);
ast_ari_response_no_content(response);
/* Parse CORS headers */
for (header = headers; header != NULL; header = header->next) {
if (strcmp(ACR_METHOD, header->name) == 0) {
acr_method = header->value;
} else if (strcmp(ACR_HEADERS, header->name) == 0) {
acr_headers = header->value;
} else if (strcmp("Origin", header->name) == 0) {
origin = header->value;
}
}
/* CORS 6.2, #1 - "If the Origin header is not present terminate this
* set of steps."
*/
if (origin == NULL) {
return;
}
/* CORS 6.2, #2 - "If the value of the Origin header is not a
* case-sensitive match for any of the values in list of origins do not
* set any additional headers and terminate this set of steps.
*
* Always matching is acceptable since the list of origins can be
* unbounded.
*
* The Origin header can only contain a single origin as the user agent
* will not follow redirects."
*/
if (!origin_allowed(origin)) {
ast_log(LOG_NOTICE, "Origin header '%s' does not match an allowed origin.\n", origin);
return;
}
/* CORS 6.2, #3 - "If there is no Access-Control-Request-Method header
* or if parsing failed, do not set any additional headers and terminate
* this set of steps."
*/
if (acr_method == NULL) {
return;
}
/* CORS 6.2, #4 - "If there are no Access-Control-Request-Headers
* headers let header field-names be the empty list."
*/
if (acr_headers == NULL) {
acr_headers = "";
}
/* CORS 6.2, #5 - "If method is not a case-sensitive match for any of
* the values in list of methods do not set any additional headers and
* terminate this set of steps."
*/
allow = ast_str_create(20);
if (!allow) {
ast_ari_response_alloc_failed(response);
return;
}
/* Go ahead and build the ACA_METHODS header at the same time */
for (m = 0; m < AST_HTTP_MAX_METHOD; ++m) {
if (handler->callbacks[m] != NULL) {
char const *m_str = ast_get_http_method(m);
if (strcmp(m_str, acr_method) == 0) {
allowed = 1;
}
ast_str_append(&allow, 0, ",%s", m_str);
}
}
if (!allowed) {
return;
}
/* CORS 6.2 #6 - "If any of the header field-names is not a ASCII
* case-insensitive match for any of the values in list of headers do
* not set any additional headers and terminate this set of steps.
*
* Note: Always matching is acceptable since the list of headers can be
* unbounded."
*/
/* CORS 6.2 #7 - "If the resource supports credentials add a single
* Access-Control-Allow-Origin header, with the value of the Origin
* header as value, and add a single Access-Control-Allow-Credentials
* header with the case-sensitive string "true" as value."
*
* Added by process_cors_request() earlier in the request.
*/
/* CORS 6.2 #8 - "Optionally add a single Access-Control-Max-Age
* header..."
*/
/* CORS 6.2 #9 - "Add one or more Access-Control-Allow-Methods headers
* consisting of (a subset of) the list of methods."
*/
ast_str_append(&response->headers, 0, "%s: OPTIONS%s\r\n",
ACA_METHODS, ast_str_buffer(allow));
/* CORS 6.2, #10 - "Add one or more Access-Control-Allow-Headers headers
* consisting of (a subset of) the list of headers.
*
* Since the list of headers can be unbounded simply returning headers
* can be enough."
*/
if (!ast_strlen_zero(acr_headers)) {
ast_str_append(&response->headers, 0, "%s: %s\r\n",
ACA_HEADERS, acr_headers);
}
}
void ast_ari_invoke(struct ast_tcptls_session_instance *ser,
const char *uri, enum ast_http_method method,
struct ast_variable *get_params, struct ast_variable *headers,
struct ast_json *body, struct ast_ari_response *response)
{
RAII_VAR(struct stasis_rest_handlers *, root, NULL, ao2_cleanup);
struct stasis_rest_handlers *handler;
struct stasis_rest_handlers *wildcard_handler = NULL;
RAII_VAR(struct ast_variable *, path_vars, NULL, ast_variables_destroy);
char *path = ast_strdupa(uri);
char *path_segment;
stasis_rest_callback callback;
root = handler = get_root_handler();
ast_assert(root != NULL);
ast_debug(3, "Finding handler for %s\n", path);
while ((path_segment = strsep(&path, "/")) && (strlen(path_segment) > 0)) {
struct stasis_rest_handlers *found_handler = NULL;
int i;
ast_uri_decode(path_segment, ast_uri_http_legacy);
ast_debug(3, " Finding handler for %s\n", path_segment);
for (i = 0; found_handler == NULL && i < handler->num_children; ++i) {
struct stasis_rest_handlers *child = handler->children[i];
if (child->is_wildcard) {
/* Record the path variable */
struct ast_variable *path_var = ast_variable_new(child->path_segment, path_segment, __FILE__);
path_var->next = path_vars;
path_vars = path_var;
wildcard_handler = child;
ast_debug(3, " Checking %s %s: Matched wildcard.\n", handler->path_segment, child->path_segment);
} else if (strcmp(child->path_segment, path_segment) == 0) {
found_handler = child;
ast_debug(3, " Checking %s %s: Explicit match with %s\n", handler->path_segment, child->path_segment, path_segment);
} else {
ast_debug(3, " Checking %s %s: Didn't match %s\n", handler->path_segment, child->path_segment, path_segment);
}
}
if (!found_handler && wildcard_handler) {
ast_debug(3, " No explicit handler found for %s. Using wildcard %s.\n",
path_segment, wildcard_handler->path_segment);
found_handler = wildcard_handler;
wildcard_handler = NULL;
}
if (found_handler == NULL) {
/* resource not found */
ast_debug(3, " Handler not found for %s\n", path_segment);
ast_ari_response_error(
response, 404, "Not Found",
"Resource not found");
return;
} else {
handler = found_handler;
}
}
ast_assert(handler != NULL);
if (method == AST_HTTP_OPTIONS) {
handle_options(handler, headers, response);
return;
}
if (method < 0 || method >= AST_HTTP_MAX_METHOD) {
add_allow_header(handler, response);
ast_ari_response_error(
response, 405, "Method Not Allowed",
"Invalid method");
return;
}
if (handler->ws_server && method == AST_HTTP_GET) {
/* WebSocket! */
ari_handle_websocket(handler->ws_server, ser, uri, method,
get_params, headers);
/* Since the WebSocket code handles the connection, we shouldn't
* do anything else; setting no_response */
response->no_response = 1;
return;
}
callback = handler->callbacks[method];
if (callback == NULL) {
add_allow_header(handler, response);
ast_ari_response_error(
response, 405, "Method Not Allowed",
"Invalid method");
return;
}
callback(ser, get_params, path_vars, headers, body, response);
if (response->message == NULL && response->response_code == 0) {
/* Really should not happen */
ast_log(LOG_ERROR, "ARI %s %s not implemented\n",
ast_get_http_method(method), uri);
ast_ari_response_error(
response, 501, "Not Implemented",
"Method not implemented");
}
}
void ast_ari_get_docs(const char *uri, const char *prefix, struct ast_variable *headers,
struct ast_ari_response *response)
{
RAII_VAR(struct ast_str *, absolute_path_builder, NULL, ast_free);
RAII_VAR(char *, absolute_api_dirname, NULL, ast_std_free);
RAII_VAR(char *, absolute_filename, NULL, ast_std_free);
struct ast_json *obj = NULL;
struct ast_variable *host = NULL;
struct ast_json_error error = {};
struct stat file_stat;
ast_debug(3, "%s(%s)\n", __func__, uri);
absolute_path_builder = ast_str_create(80);
if (absolute_path_builder == NULL) {
ast_ari_response_alloc_failed(response);
return;
}
/* absolute path to the rest-api directory */
ast_str_append(&absolute_path_builder, 0, "%s", ast_config_AST_DATA_DIR);
ast_str_append(&absolute_path_builder, 0, "/rest-api/");
absolute_api_dirname = realpath(ast_str_buffer(absolute_path_builder), NULL);
if (absolute_api_dirname == NULL) {
ast_log(LOG_ERROR, "Error determining real directory for rest-api\n");
ast_ari_response_error(
response, 500, "Internal Server Error",
"Cannot find rest-api directory");
return;
}
/* absolute path to the requested file */
ast_str_append(&absolute_path_builder, 0, "%s", uri);
absolute_filename = realpath(ast_str_buffer(absolute_path_builder), NULL);
if (absolute_filename == NULL) {
switch (errno) {
case ENAMETOOLONG:
case ENOENT:
case ENOTDIR:
ast_ari_response_error(
response, 404, "Not Found",
"Resource not found");
break;
case EACCES:
ast_ari_response_error(
response, 403, "Forbidden",
"Permission denied");
break;
default:
ast_log(LOG_ERROR,
"Error determining real path for uri '%s': %s\n",
uri, strerror(errno));
ast_ari_response_error(
response, 500, "Internal Server Error",
"Cannot find file");
break;
}
return;
}
if (!ast_begins_with(absolute_filename, absolute_api_dirname)) {
/* HACKERZ! */
ast_log(LOG_ERROR,
"Invalid attempt to access '%s' (not in %s)\n",
absolute_filename, absolute_api_dirname);
ast_ari_response_error(
response, 404, "Not Found",
"Resource not found");
return;
}
if (stat(absolute_filename, &file_stat) == 0) {
if (!(file_stat.st_mode & S_IFREG)) {
/* Not a file */
ast_ari_response_error(
response, 403, "Forbidden",
"Invalid access");
return;
}
} else {
/* Does not exist */
ast_ari_response_error(
response, 404, "Not Found",
"Resource not found");
return;
}
/* Load resource object from file */
obj = ast_json_load_new_file(absolute_filename, &error);
if (obj == NULL) {
ast_log(LOG_ERROR, "Error parsing resource file: %s:%d(%d) %s\n",
error.source, error.line, error.column, error.text);
ast_ari_response_error(
response, 500, "Internal Server Error",
"Yikes! Cannot parse resource");
return;
}
/* Update the basePath properly */
if (ast_json_object_get(obj, "basePath") != NULL) {
for (host = headers; host; host = host->next) {
if (strcasecmp(host->name, "Host") == 0) {
break;
}
}
if (host != NULL) {
if (prefix != NULL && strlen(prefix) > 0) {
ast_json_object_set(
obj, "basePath",
ast_json_stringf("http://%s%s/ari", host->value,prefix));
} else {
ast_json_object_set(
obj, "basePath",
ast_json_stringf("http://%s/ari", host->value));
}
} else {
/* Without the host, we don't have the basePath */
ast_json_object_del(obj, "basePath");
}
}
ast_ari_response_ok(response, obj);
}
static void remove_trailing_slash(const char *uri,
struct ast_ari_response *response)
{
char *slashless = ast_strdupa(uri);
slashless[strlen(slashless) - 1] = '\0';
/* While it's tempting to redirect the client to the slashless URL,
* that is problematic. A 302 Found is the most appropriate response,
* but most clients issue a GET on the location you give them,
* regardless of the method of the original request.
*
* While there are some ways around this, it gets into a lot of client
* specific behavior and corner cases in the HTTP standard. There's also
* very little practical benefit of redirecting; only GET and HEAD can
* be redirected automagically; all other requests "MUST NOT
* automatically redirect the request unless it can be confirmed by the
* user, since this might change the conditions under which the request
* was issued."
*
* Given all of that, a 404 with a nice message telling them what to do
* is probably our best bet.
*/
ast_ari_response_error(response, 404, "Not Found",
"ARI URLs do not end with a slash. Try /ari/%s", slashless);
}
/*!
* \brief Handle CORS headers for simple requests.
*
* See http://www.w3.org/TR/cors/ for the spec. Especially section 6.1.
*/
static void process_cors_request(struct ast_variable *headers,
struct ast_ari_response *response)
{
char const *origin = NULL;
struct ast_variable *header;
/* Parse CORS headers */
for (header = headers; header != NULL; header = header->next) {
if (strcmp("Origin", header->name) == 0) {
origin = header->value;
}
}
/* CORS 6.1, #1 - "If the Origin header is not present terminate this
* set of steps."
*/
if (origin == NULL) {
return;
}
/* CORS 6.1, #2 - "If the value of the Origin header is not a
* case-sensitive match for any of the values in list of origins, do not
* set any additional headers and terminate this set of steps.
*
* Note: Always matching is acceptable since the list of origins can be
* unbounded."
*/
if (!origin_allowed(origin)) {
ast_log(LOG_NOTICE, "Origin header '%s' does not match an allowed origin.\n", origin);
return;
}
/* CORS 6.1, #3 - "If the resource supports credentials add a single
* Access-Control-Allow-Origin header, with the value of the Origin
* header as value, and add a single Access-Control-Allow-Credentials
* header with the case-sensitive string "true" as value.
*
* Otherwise, add a single Access-Control-Allow-Origin header, with
* either the value of the Origin header or the string "*" as value."
*/
ast_str_append(&response->headers, 0,
"Access-Control-Allow-Origin: %s\r\n", origin);
ast_str_append(&response->headers, 0,
"Access-Control-Allow-Credentials: true\r\n");
/* CORS 6.1, #4 - "If the list of exposed headers is not empty add one
* or more Access-Control-Expose-Headers headers, with as values the
* header field names given in the list of exposed headers."
*
* No exposed headers; skipping
*/
}
enum ast_json_encoding_format ast_ari_json_format(void)
{
RAII_VAR(struct ast_ari_conf *, cfg, NULL, ao2_cleanup);
cfg = ast_ari_config_get();
return cfg->general->format;
}
/*!
* \brief Authenticate a <code>?api_key=userid:password</code>
*
* \param api_key API key query parameter
* \return User object for the authenticated user.
* \retval NULL if authentication failed.
*/
static struct ast_ari_conf_user *authenticate_api_key(const char *api_key)
{
RAII_VAR(char *, copy, NULL, ast_free);
char *username;
char *password;
password = copy = ast_strdup(api_key);
if (!copy) {
return NULL;
}
username = strsep(&password, ":");
if (!password) {
ast_log(LOG_WARNING, "Invalid api_key\n");
return NULL;
}
return ast_ari_config_validate_user(username, password);
}
/*!
* \brief Authenticate an HTTP request.
*
* \param get_params GET parameters of the request.
* \param headers HTTP headers.
* \return User object for the authenticated user.
* \retval NULL if authentication failed.
*/
static struct ast_ari_conf_user *authenticate_user(struct ast_variable *get_params,
struct ast_variable *headers)
{
RAII_VAR(struct ast_http_auth *, http_auth, NULL, ao2_cleanup);
struct ast_variable *v;
/* HTTP Basic authentication */
http_auth = ast_http_get_auth(headers);
if (http_auth) {
return ast_ari_config_validate_user(http_auth->userid,
http_auth->password);
}
/* ?api_key authentication */
for (v = get_params; v; v = v->next) {
if (strcasecmp("api_key", v->name) == 0) {
return authenticate_api_key(v->value);
}
}
return NULL;
}
/*!
* \internal
* \brief ARI HTTP handler.
*
* This handler takes the HTTP request and turns it into the appropriate
* RESTful request (conversion to JSON, routing, etc.)
*
* \param ser TCP session.
* \param urih URI handler.
* \param uri URI requested.
* \param method HTTP method.
* \param get_params HTTP \c GET params.
* \param headers HTTP headers.
*/
static int ast_ari_callback(struct ast_tcptls_session_instance *ser,
const struct ast_http_uri *urih,
const char *uri,
enum ast_http_method method,
struct ast_variable *get_params,
struct ast_variable *headers)
{
RAII_VAR(struct ast_ari_conf *, conf, NULL, ao2_cleanup);
RAII_VAR(struct ast_str *, response_body, ast_str_create(256), ast_free);
RAII_VAR(struct ast_ari_conf_user *, user, NULL, ao2_cleanup);
struct ast_ari_response response = { .fd = -1, 0 };
RAII_VAR(struct ast_variable *, post_vars, NULL, ast_variables_destroy);
struct ast_variable *var;
const char *app_name = NULL;
RAII_VAR(struct ast_json *, body, ast_json_null(), ast_json_unref);
int debug_app = 0;
if (!response_body) {
ast_http_request_close_on_completion(ser);
ast_http_error(ser, 500, "Server Error", "Out of memory");
return 0;
}
response.headers = ast_str_create(40);
if (!response.headers) {
ast_http_request_close_on_completion(ser);
ast_http_error(ser, 500, "Server Error", "Out of memory");
return 0;
}
conf = ast_ari_config_get();
if (!conf || !conf->general) {
ast_free(response.headers);
ast_http_request_close_on_completion(ser);
ast_http_error(ser, 500, "Server Error", "URI handler config missing");
return 0;
}
process_cors_request(headers, &response);
/* Process form data from a POST. It could be mixed with query
* parameters, which seems a bit odd. But it's allowed, so that's okay
* with us.
*/
post_vars = ast_http_get_post_vars(ser, headers);
if (!post_vars) {
switch (errno) {
case EFBIG:
ast_ari_response_error(&response, 413,
"Request Entity Too Large",
"Request body too large");
goto request_failed;
case ENOMEM:
ast_http_request_close_on_completion(ser);
ast_ari_response_error(&response, 500,
"Internal Server Error",
"Out of memory");
goto request_failed;
case EIO:
ast_ari_response_error(&response, 400,
"Bad Request", "Error parsing request body");
goto request_failed;
}
/* Look for a JSON request entity only if there were no post_vars.
* If there were post_vars, then the request body would already have
* been consumed and can not be read again.
*/
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 request_failed;
case ENOMEM:
ast_ari_response_error(&response, 500, "Internal Server Error", "Error processing request");
goto request_failed;
case EIO:
ast_ari_response_error(&response, 400, "Bad Request", "Error parsing request body");
goto request_failed;
}
}
}
if (get_params == NULL) {
get_params = post_vars;
} else if (get_params && post_vars) {
/* Has both post_vars and get_params */
struct ast_variable *last_var = post_vars;
while (last_var->next) {
last_var = last_var->next;
}
/* The duped get_params will get freed when post_vars gets
* ast_variables_destroyed.
*/
last_var->next = ast_variables_dup(get_params);
get_params = post_vars;
}
/* At this point, get_params will contain post_vars (if any) */
app_name = ast_variable_find_in_list(get_params, "app");
if (!app_name) {
struct ast_json *app = ast_json_object_get(body, "app");
app_name = (app ? ast_json_string_get(app) : NULL);
}
/* stasis_app_get_debug_by_name returns an "||" of the app's debug flag
* and the global debug flag.
*/
debug_app = stasis_app_get_debug_by_name(app_name);
if (debug_app) {
struct ast_str *buf = ast_str_create(512);
char *str = ast_json_dump_string_format(body, ast_ari_json_format());
if (!buf || (body && !str)) {
ast_http_request_close_on_completion(ser);
ast_ari_response_error(&response, 500, "Server Error", "Out of memory");
ast_json_free(str);
ast_free(buf);
goto request_failed;
}
ast_str_append(&buf, 0, "<--- ARI request received from: %s --->\n",
ast_sockaddr_stringify(&ser->remote_address));
for (var = headers; var; var = var->next) {
ast_str_append(&buf, 0, "%s: %s\n", var->name, var->value);
}
for (var = get_params; var; var = var->next) {
ast_str_append(&buf, 0, "%s: %s\n", var->name, var->value);
}
ast_verbose("%sbody:\n%s\n\n", ast_str_buffer(buf), S_OR(str, ""));
ast_json_free(str);
ast_free(buf);
}
user = authenticate_user(get_params, headers);
if (response.response_code > 0) {
/* POST parameter processing error. Do nothing. */
} else if (!user) {
/* Per RFC 2617, section 1.2: The 401 (Unauthorized) response
* message is used by an origin server to challenge the
* authorization of a user agent. This response MUST include a
* WWW-Authenticate header field containing at least one
* challenge applicable to the requested resource.
*/
ast_ari_response_error(&response, 401, "Unauthorized", "Authentication required");
/* Section 1.2:
* realm = "realm" "=" realm-value
* realm-value = quoted-string
* Section 2:
* challenge = "Basic" realm
*/
ast_str_append(&response.headers, 0,
"WWW-Authenticate: Basic realm=\"%s\"\r\n",
conf->general->auth_realm);
} else if (!ast_fully_booted) {
ast_http_request_close_on_completion(ser);
ast_ari_response_error(&response, 503, "Service Unavailable", "Asterisk not booted");
} else if (user->read_only && method != AST_HTTP_GET && method != AST_HTTP_OPTIONS) {
ast_ari_response_error(&response, 403, "Forbidden", "Write access denied");
} else if (ast_ends_with(uri, "/")) {
remove_trailing_slash(uri, &response);
} else if (ast_begins_with(uri, "api-docs/")) {
/* Serving up API docs */
if (method != AST_HTTP_GET) {
ast_ari_response_error(&response, 405, "Method Not Allowed", "Unsupported method");
} else {
/* Skip the api-docs prefix */
ast_ari_get_docs(strchr(uri, '/') + 1, urih->prefix, headers, &response);
}
} else {
/* Other RESTful resources */
ast_ari_invoke(ser, uri, method, get_params, headers, body,
&response);
}
if (response.no_response) {
/* The handler indicates no further response is necessary.
* Probably because it already handled it */
ast_free(response.headers);
return 0;
}
request_failed:
/* If you explicitly want to have no content, set message to
* ast_json_null().
*/
ast_assert(response.message != NULL);
ast_assert(response.response_code > 0);
/* response.message could be NULL, in which case the empty response_body
* is correct
*/
if (response.message && !ast_json_is_null(response.message)) {
ast_str_append(&response.headers, 0,
"Content-type: application/json\r\n");
if (ast_json_dump_str_format(response.message, &response_body,
conf->general->format) != 0) {
/* Error encoding response */
response.response_code = 500;
response.response_text = "Internal Server Error";
ast_str_set(&response_body, 0, "%s", "");
ast_str_set(&response.headers, 0, "%s", "");
}
}
if (debug_app) {
ast_verbose("<--- Sending ARI response to %s --->\n%d %s\n%s%s\n\n",
ast_sockaddr_stringify(&ser->remote_address), response.response_code,
response.response_text, ast_str_buffer(response.headers),
ast_str_buffer(response_body));
}
ast_http_send(ser, method, response.response_code,
response.response_text, response.headers, response_body,
response.fd != -1 ? response.fd : 0, 0);
/* ast_http_send takes ownership, so we don't have to free them */
response_body = NULL;
ast_json_unref(response.message);
if (response.fd >= 0) {
close(response.fd);
}
return 0;
}
static struct ast_http_uri http_uri = {
.callback = ast_ari_callback,
.description = "Asterisk RESTful API",
.uri = "ari",
.has_subtree = 1,
.data = NULL,
.key = __FILE__,
.no_decode_uri = 1,
};
static int unload_module(void)
{
ast_ari_cli_unregister();
if (is_enabled()) {
ast_debug(3, "Disabling ARI\n");
ast_http_uri_unlink(&http_uri);
}
ast_ari_config_destroy();
ao2_cleanup(root_handler);
root_handler = NULL;
ast_mutex_destroy(&root_handler_lock);
ast_json_unref(oom_json);
oom_json = NULL;
return 0;
}
static int load_module(void)
{
ast_mutex_init(&root_handler_lock);
/* root_handler may have been built during a declined load */
if (!root_handler) {
root_handler = root_handler_create();
}
if (!root_handler) {
return AST_MODULE_LOAD_DECLINE;
}
/* oom_json may have been built during a declined load */
if (!oom_json) {
oom_json = ast_json_pack(
"{s: s}", "error", "Allocation failed");
}
if (!oom_json) {
/* Ironic */
unload_module();
return AST_MODULE_LOAD_DECLINE;
}
if (ast_ari_config_init() != 0) {
unload_module();
return AST_MODULE_LOAD_DECLINE;
}
if (is_enabled()) {
ast_debug(3, "ARI enabled\n");
ast_http_uri_link(&http_uri);
} else {
ast_debug(3, "ARI disabled\n");
}
if (ast_ari_cli_register() != 0) {
unload_module();
return AST_MODULE_LOAD_DECLINE;
}
return AST_MODULE_LOAD_SUCCESS;
}
static int reload_module(void)
{
char was_enabled = is_enabled();
if (ast_ari_config_reload() != 0) {
return AST_MODULE_LOAD_DECLINE;
}
if (was_enabled && !is_enabled()) {
ast_debug(3, "Disabling ARI\n");
ast_http_uri_unlink(&http_uri);
} else if (!was_enabled && is_enabled()) {
ast_debug(3, "Enabling ARI\n");
ast_http_uri_link(&http_uri);
}
return AST_MODULE_LOAD_SUCCESS;
}
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "Asterisk RESTful Interface",
.support_level = AST_MODULE_SUPPORT_CORE,
.load = load_module,
.unload = unload_module,
.reload = reload_module,
.optional_modules = "res_http_websocket",
.requires = "http,res_stasis",
.load_pri = AST_MODPRI_APP_DEPEND,
);