http.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2006, Digium, Inc.
 *
 * Mark Spencer <markster@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 server for AMI access
 *
 * \author Mark Spencer <markster@digium.com>
 *
 * This program implements a tiny http server
 * and was inspired by micro-httpd by Jef Poskanzer
 *
 * GMime http://spruce.sourceforge.net/gmime/
 *
 * \ref AstHTTP - AMI over the http protocol
 */
 
/*! \li \ref http.c uses the configuration file \ref http.conf
 * \addtogroup configuration_file
 */
 
/*! \page http.conf http.conf
 * \verbinclude http.conf.sample
 */
 
/*** MODULEINFO
    <support_level>core</support_level>
 ***/
 
#include "asterisk.h"
 
#include <time.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <signal.h>
#include <fcntl.h>
 
#include "asterisk/paths.h" /* use ast_config_AST_DATA_DIR */
#include "asterisk/acl.h"
#include "asterisk/cli.h"
#include "asterisk/tcptls.h"
#include "asterisk/http.h"
#include "asterisk/utils.h"
#include "asterisk/strings.h"
#include "asterisk/config.h"
#include "asterisk/stringfields.h"
#include "asterisk/ast_version.h"
#include "asterisk/manager.h"
#include "asterisk/module.h"
#include "asterisk/astobj2.h"
#include "asterisk/netsock2.h"
#include "asterisk/json.h"
 
#define MAX_PREFIX 80
#define DEFAULT_PORT 8088
#define DEFAULT_TLS_PORT 8089
#define DEFAULT_SESSION_LIMIT 100
/*! (ms) Idle time waiting for data. */
#define DEFAULT_SESSION_INACTIVITY 30000
/*! (ms) Min timeout for initial HTTP request to start coming in. */
#define MIN_INITIAL_REQUEST_TIMEOUT 10000
/*! (ms) Idle time between HTTP requests */
#define DEFAULT_SESSION_KEEP_ALIVE 15000
/*! Max size for the http server name */
#define MAX_SERVER_NAME_LENGTH 128
/*! Max size for the http response header */
#define DEFAULT_RESPONSE_HEADER_LENGTH 512
 
/*! Maximum application/json or application/x-www-form-urlencoded body content length. */
#if !defined(LOW_MEMORY)
#define MAX_CONTENT_LENGTH 40960
#else
#define MAX_CONTENT_LENGTH 1024
#endif  /* !defined(LOW_MEMORY) */
 
/*! Initial response body length. */
#if !defined(LOW_MEMORY)
#define INITIAL_RESPONSE_BODY_BUFFER 1024
#else
#define INITIAL_RESPONSE_BODY_BUFFER 512
#endif  /* !defined(LOW_MEMORY) */
 
/*! Maximum line length for HTTP requests. */
#if !defined(LOW_MEMORY)
#define MAX_HTTP_LINE_LENGTH 4096
#else
#define MAX_HTTP_LINE_LENGTH 1024
#endif  /* !defined(LOW_MEMORY) */
 
static char http_server_name[MAX_SERVER_NAME_LENGTH];
 
static int session_limit = DEFAULT_SESSION_LIMIT;
static int session_inactivity = DEFAULT_SESSION_INACTIVITY;
static int session_keep_alive = DEFAULT_SESSION_KEEP_ALIVE;
static int session_count = 0;
 
static struct ast_tls_config http_tls_cfg;
 
static void *httpd_helper_thread(void *arg);
 
/*!
 * For standard configuration we have up to two accepting threads,
 * one for http, one for https. If TEST_FRAMEWORK is enabled it's
 * possible to have more than one running http server.
 */
struct ast_http_server {
    struct ast_tcptls_session_args args;
    char *name;
    char *address;
};
 
/*!
 * The default configured HTTP server
 */
struct ast_http_server *global_http_server = NULL;
 
static struct ast_tcptls_session_args https_desc = {
    .accept_fd = -1,
    .master = AST_PTHREADT_NULL,
    .tls_cfg = &http_tls_cfg,
    .poll_timeout = -1,
    .name = "https server",
    .accept_fn = ast_tcptls_server_root,
    .worker_fn = httpd_helper_thread,
};
 
static AST_RWLIST_HEAD_STATIC(uris, ast_http_uri);  /*!< list of supported handlers */
 
/* all valid URIs must be prepended by the string in prefix. */
static char prefix[MAX_PREFIX];
static int static_uri_enabled;
static int status_uri_enabled;
 
/*! \brief Limit the kinds of files we're willing to serve up */
static struct {
    const char *ext;
    const char *mtype;
} mimetypes[] = {
    { "png", "image/png" },
    { "xml", "text/xml" },
    { "jpg", "image/jpeg" },
    { "js", "application/x-javascript" },
    { "wav", "audio/x-wav" },
    { "mp3", "audio/mpeg" },
    { "svg", "image/svg+xml" },
    { "svgz", "image/svg+xml" },
    { "gif", "image/gif" },
    { "html", "text/html" },
    { "htm", "text/html" },
    { "css", "text/css" },
    { "cnf", "text/plain" },
    { "cfg", "text/plain" },
    { "bin", "application/octet-stream" },
    { "sbn", "application/octet-stream" },
    { "ld", "application/octet-stream" },
};
 
struct http_uri_redirect {
    AST_LIST_ENTRY(http_uri_redirect) entry;
    char *dest;
    char target[0];
};
 
static AST_RWLIST_HEAD_STATIC(uri_redirects, http_uri_redirect);
 
/*! \brief Per-path ACL restriction */
struct http_restriction {
    AST_LIST_ENTRY(http_restriction) entry;
    struct ast_acl_list *acl;
    char path[];
};
 
AST_LIST_HEAD_NOLOCK(http_restriction_list, http_restriction);
 
static AST_RWLIST_HEAD_STATIC(restrictions, http_restriction);
 
static int check_restriction_acl(struct ast_tcptls_session_instance *ser, const char *uri);
 
static const struct ast_cfhttp_methods_text {
    enum ast_http_method method;
    const char *text;
} ast_http_methods_text[] = {
    { AST_HTTP_UNKNOWN,     "UNKNOWN" },
    { AST_HTTP_GET,         "GET" },
    { AST_HTTP_POST,        "POST" },
    { AST_HTTP_HEAD,        "HEAD" },
    { AST_HTTP_PUT,         "PUT" },
    { AST_HTTP_DELETE,      "DELETE" },
    { AST_HTTP_OPTIONS,     "OPTIONS" },
};
 
const char *ast_get_http_method(enum ast_http_method method)
{
    int x;
 
    for (x = 0; x < ARRAY_LEN(ast_http_methods_text); x++) {
        if (ast_http_methods_text[x].method == method) {
            return ast_http_methods_text[x].text;
        }
    }
 
    return NULL;
}
 
enum ast_http_method ast_get_http_method_from_string(const char *method)
{
    int x;
 
    for (x = 0; x < ARRAY_LEN(ast_http_methods_text); x++) {
        if (ast_strings_equal(method, ast_http_methods_text[x].text)) {
            return ast_http_methods_text[x].method;
        }
    }
 
    return AST_HTTP_UNKNOWN;
}
 
const char *ast_http_ftype2mtype(const char *ftype)
{
    int x;
 
    if (ftype) {
        for (x = 0; x < ARRAY_LEN(mimetypes); x++) {
            if (!strcasecmp(ftype, mimetypes[x].ext)) {
                return mimetypes[x].mtype;
            }
        }
    }
    return NULL;
}
 
uint32_t ast_http_manid_from_vars(struct ast_variable *headers)
{
    uint32_t mngid = 0;
    struct ast_variable *v, *cookies;
 
    cookies = ast_http_get_cookies(headers);
    for (v = cookies; v; v = v->next) {
        if (!strcasecmp(v->name, "mansession_id")) {
            sscanf(v->value, "%30x", &mngid);
            break;
        }
    }
    ast_variables_destroy(cookies);
    return mngid;
}
 
void ast_http_prefix(char *buf, int len)
{
    if (buf) {
        ast_copy_string(buf, prefix, len);
    }
}
 
static int static_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_vars,
    struct ast_variable *headers)
{
    char *path;
    const char *ftype;
    const char *mtype;
    char wkspace[80];
    struct stat st;
    int len;
    int fd;
    struct ast_str *http_header;
    struct timeval tv;
    struct ast_tm tm;
    char timebuf[80], etag[23];
    struct ast_variable *v;
    int not_modified = 0;
 
    if (method != AST_HTTP_GET && method != AST_HTTP_HEAD) {
        ast_http_error(ser, 501, "Not Implemented", "Attempt to use unimplemented / unsupported method");
        return 0;
    }
 
    /* Yuck.  I'm not really sold on this, but if you don't deliver static content it
     * makes your configuration substantially more challenging, but this seems like a
     * rather irritating feature creep on Asterisk.
     *
     * XXX: It is not clear to me what this comment means or if it is any longer
     *      relevant. */
    if (ast_strlen_zero(uri)) {
        goto out403;
    }
 
    /* Disallow any funny filenames at all (checking first character only??) */
    if ((uri[0] < 33) || strchr("./|~@#$%^&*() \t", uri[0])) {
        goto out403;
    }
 
    if (strstr(uri, "/..")) {
        goto out403;
    }
 
    if ((ftype = strrchr(uri, '.'))) {
        ftype++;
    }
 
    if (!(mtype = ast_http_ftype2mtype(ftype))) {
        snprintf(wkspace, sizeof(wkspace), "text/%s", S_OR(ftype, "plain"));
        mtype = wkspace;
    }
 
    /* Cap maximum length */
    if ((len = strlen(uri) + strlen(ast_config_AST_DATA_DIR) + strlen("/static-http/") + 5) > 1024) {
        goto out403;
    }
 
    path = ast_alloca(len);
    sprintf(path, "%s/static-http/%s", ast_config_AST_DATA_DIR, uri);
    if (stat(path, &st)) {
        goto out404;
    }
 
    if (S_ISDIR(st.st_mode)) {
        goto out404;
    }
 
    if (strstr(path, "/private/") && !astman_is_authed(ast_http_manid_from_vars(headers))) {
        goto out403;
    }
 
    fd = open(path, O_RDONLY);
    if (fd < 0) {
        goto out403;
    }
 
    /* make "Etag:" http header value */
    snprintf(etag, sizeof(etag), "\"%ld\"", (long)st.st_mtime);
 
    /* make "Last-Modified:" http header value */
    tv.tv_sec = st.st_mtime;
    tv.tv_usec = 0;
    ast_strftime(timebuf, sizeof(timebuf), "%a, %d %b %Y %H:%M:%S GMT", ast_localtime(&tv, &tm, "GMT"));
 
    /* check received "If-None-Match" request header and Etag value for file */
    for (v = headers; v; v = v->next) {
        if (!strcasecmp(v->name, "If-None-Match")) {
            if (!strcasecmp(v->value, etag)) {
                not_modified = 1;
            }
            break;
        }
    }
 
    http_header = ast_str_create(255);
    if (!http_header) {
        ast_http_request_close_on_completion(ser);
        ast_http_error(ser, 500, "Server Error", "Out of memory");
        close(fd);
        return 0;
    }
 
    ast_str_set(&http_header, 0, "Content-type: %s\r\n"
        "ETag: %s\r\n"
        "Last-Modified: %s\r\n",
        mtype,
        etag,
        timebuf);
 
    /* ast_http_send() frees http_header, so we don't need to do it before returning */
    if (not_modified) {
        ast_http_send(ser, method, 304, "Not Modified", http_header, NULL, 0, 1);
    } else {
        ast_http_send(ser, method, 200, NULL, http_header, NULL, fd, 1); /* static content flag is set */
    }
    close(fd);
    return 0;
 
out404:
    ast_http_error(ser, 404, "Not Found", "The requested URL was not found on this server.");
    return 0;
 
out403:
    ast_http_request_close_on_completion(ser);
    ast_http_error(ser, 403, "Access Denied", "You do not have permission to access the requested URL.");
    return 0;
}
 
static void str_append_escaped(struct ast_str **str, const char *in)
{
    const char *cur = in;
 
    while(*cur) {
        switch (*cur) {
        case '<':
            ast_str_append(str, 0, "&lt;");
            break;
        case '>':
            ast_str_append(str, 0, "&gt;");
            break;
        case '&':
            ast_str_append(str, 0, "&amp;");
            break;
        case '"':
            ast_str_append(str, 0, "&quot;");
            break;
        default:
            ast_str_append(str, 0, "%c", *cur);
            break;
        }
        cur++;
    }
 
    return;
}
 
static int httpstatus_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_vars,
    struct ast_variable *headers)
{
    struct ast_str *out;
    struct ast_variable *v, *cookies = NULL;
 
    if (method != AST_HTTP_GET && method != AST_HTTP_HEAD) {
        ast_http_error(ser, 501, "Not Implemented", "Attempt to use unimplemented / unsupported method");
        return 0;
    }
 
    out = ast_str_create(512);
    if (!out) {
        ast_http_request_close_on_completion(ser);
        ast_http_error(ser, 500, "Server Error", "Out of memory");
        return 0;
    }
 
    ast_str_append(&out, 0,
        "<html><title>Asterisk HTTP Status</title>\r\n"
        "<body bgcolor=\"#ffffff\">\r\n"
        "<table bgcolor=\"#f1f1f1\" align=\"center\"><tr><td bgcolor=\"#e0e0ff\" colspan=\"2\" width=\"500\">\r\n"
        "<h2>&nbsp;&nbsp;Asterisk&trade; HTTP Status</h2></td></tr>\r\n");
 
    ast_str_append(&out, 0, "<tr><td><i>Server</i></td><td><b>%s</b></td></tr>\r\n", http_server_name);
    ast_str_append(&out, 0, "<tr><td><i>Prefix</i></td><td><b>%s</b></td></tr>\r\n", prefix);
    if (global_http_server) {
        ast_str_append(&out, 0, "<tr><td><i>Bind Address</i></td><td><b>%s</b></td></tr>\r\n",
                   ast_sockaddr_stringify(&global_http_server->args.old_address));
    }
    if (http_tls_cfg.enabled) {
        ast_str_append(&out, 0, "<tr><td><i>TLS Bind Address</i></td><td><b>%s</b></td></tr>\r\n",
                   ast_sockaddr_stringify(&https_desc.old_address));
    }
    ast_str_append(&out, 0, "<tr><td colspan=\"2\"><hr></td></tr>\r\n");
    for (v = get_vars; v; v = v->next) {
        ast_str_append(&out, 0, "<tr><td><i>Submitted GET Variable '");
        str_append_escaped(&out, v->name);
        ast_str_append(&out, 0, "'</i></td><td>");
        str_append_escaped(&out, v->value);
        ast_str_append(&out, 0, "</td></tr>\r\n");
    }
    ast_str_append(&out, 0, "<tr><td colspan=\"2\"><hr></td></tr>\r\n");
 
    cookies = ast_http_get_cookies(headers);
    for (v = cookies; v; v = v->next) {
        ast_str_append(&out, 0, "<tr><td><i>Cookie '");
        str_append_escaped(&out, v->name);
        ast_str_append(&out, 0, "'</i></td><td>");
        str_append_escaped(&out, v->value);
        ast_str_append(&out, 0, "</td></tr>\r\n");
    }
    ast_variables_destroy(cookies);
 
    ast_str_append(&out, 0, "</table><center><font size=\"-1\"><i>Asterisk and Digium are registered trademarks of Digium, Inc.</i></font></center></body></html>\r\n");
    ast_http_send(ser, method, 200, NULL, NULL, out, 0, 0);
    return 0;
}
 
static struct ast_http_uri status_uri = {
    .callback = httpstatus_callback,
    .description = "Asterisk HTTP General Status",
    .uri = "httpstatus",
    .has_subtree = 0,
    .data = NULL,
    .key = __FILE__,
};
 
static struct ast_http_uri static_uri = {
    .callback = static_callback,
    .description = "Asterisk HTTP Static Delivery",
    .uri = "static",
    .has_subtree = 1,
    .data = NULL,
    .key= __FILE__,
};
 
enum http_private_flags {
    /*! TRUE if the HTTP request has a body. */
    HTTP_FLAG_HAS_BODY = (1 << 0),
    /*! TRUE if the HTTP request body has been read. */
    HTTP_FLAG_BODY_READ = (1 << 1),
    /*! TRUE if the HTTP request must close when completed. */
    HTTP_FLAG_CLOSE_ON_COMPLETION = (1 << 2),
};
 
/*! HTTP tcptls worker_fn private data. */
struct http_worker_private_data {
    /*! Body length or -1 if chunked.  Valid if HTTP_FLAG_HAS_BODY is TRUE. */
    int body_length;
    /*! HTTP body tracking flags */
    struct ast_flags flags;
};
 
void ast_http_send(struct ast_tcptls_session_instance *ser,
    enum ast_http_method method, int status_code, const char *status_title,
    struct ast_str *http_header, struct ast_str *out, int fd,
    unsigned int static_content)
{
    struct timeval now = ast_tvnow();
    struct ast_tm tm;
    char timebuf[80];
    char buf[256];
    int len;
    int content_length = 0;
    int close_connection;
    struct ast_str *server_header_field = ast_str_create(MAX_SERVER_NAME_LENGTH);
    int send_content;
 
    if (!ser || !server_header_field) {
        /* The connection is not open. */
        ast_free(http_header);
        ast_free(out);
        ast_free(server_header_field);
        return;
    }
 
    if(!ast_strlen_zero(http_server_name)) {
        ast_str_set(&server_header_field,
                    0,
                    "Server: %s\r\n",
                    http_server_name);
    }
 
    /*
     * We shouldn't be sending non-final status codes to this
     * function because we may close the connection before
     * returning.
     */
    ast_assert(200 <= status_code);
 
    if (session_keep_alive <= 0) {
        close_connection = 1;
    } else {
        struct http_worker_private_data *request;
 
        request = ser->private_data;
        if (!request
            || ast_test_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION)
            || ast_http_body_discard(ser)) {
            close_connection = 1;
        } else {
            close_connection = 0;
        }
    }
 
    ast_strftime(timebuf, sizeof(timebuf), "%a, %d %b %Y %H:%M:%S GMT", ast_localtime(&now, &tm, "GMT"));
 
    /* calc content length */
    if (out) {
        content_length += ast_str_strlen(out);
    }
 
    if (fd) {
        content_length += lseek(fd, 0, SEEK_END);
        lseek(fd, 0, SEEK_SET);
    }
 
    send_content = method != AST_HTTP_HEAD || status_code >= 400;
 
    /* send http header */
    if (ast_iostream_printf(ser->stream,
        "HTTP/1.1 %d %s\r\n"
        "%s"
        "Date: %s\r\n"
        "%s"
        "%s"
        "%s"
        "Content-Length: %d\r\n"
        "\r\n"
        "%s",
        status_code, status_title ? status_title : "OK",
        ast_str_buffer(server_header_field),
        timebuf,
        close_connection ? "Connection: close\r\n" : "",
        static_content ? "" : "Cache-Control: no-cache, no-store\r\n",
        http_header ? ast_str_buffer(http_header) : "",
        content_length,
        send_content && out && ast_str_strlen(out) ? ast_str_buffer(out) : ""
        ) <= 0) {
        ast_debug(1, "ast_iostream_printf() failed: %s\n", strerror(errno));
        close_connection = 1;
    } else if (send_content && fd) {
        /* send file content */
        while ((len = read(fd, buf, sizeof(buf))) > 0) {
            if (ast_iostream_write(ser->stream, buf, len) != len) {
                ast_debug(1, "ast_iostream_write() failed: %s\n", strerror(errno));
                close_connection = 1;
                break;
            }
        }
    }
 
    ast_free(http_header);
    ast_free(out);
    ast_free(server_header_field);
 
    if (close_connection) {
        ast_debug(1, "HTTP closing session.  status_code:%d\n", status_code);
        ast_tcptls_close_session_file(ser);
    } else {
        ast_debug(1, "HTTP keeping session open.  status_code:%d\n", status_code);
    }
}
 
void ast_http_create_response(struct ast_tcptls_session_instance *ser, int status_code,
    const char *status_title, struct ast_str *http_header_data, const char *text)
{
    char server_name[MAX_SERVER_NAME_LENGTH];
    struct ast_str *server_address = ast_str_create(MAX_SERVER_NAME_LENGTH);
    struct ast_str *out = ast_str_create(INITIAL_RESPONSE_BODY_BUFFER);
 
    if (!http_header_data || !server_address || !out) {
        ast_free(http_header_data);
        ast_free(server_address);
        ast_free(out);
        if (ser) {
            ast_debug(1, "HTTP closing session. OOM.\n");
            ast_tcptls_close_session_file(ser);
        }
        return;
    }
 
    if(!ast_strlen_zero(http_server_name)) {
        ast_xml_escape(http_server_name, server_name, sizeof(server_name));
        ast_str_set(&server_address,
                    0,
                    "<address>%s</address>\r\n",
                    server_name);
    }
 
    ast_str_set(&out,
                0,
                "<!DOCTYPE HTML PUBLIC \"-//IETF//DTD HTML 2.0//EN\">\r\n"
                "<html><head>\r\n"
                "<title>%d %s</title>\r\n"
                "</head><body>\r\n"
                "<h1>%s</h1>\r\n"
                "<p>%s</p>\r\n"
                "<hr />\r\n"
                "%s"
                "</body></html>\r\n",
                status_code,
                status_title,
                status_title,
                text ? text : "",
                ast_str_buffer(server_address));
 
    ast_free(server_address);
 
    ast_http_send(ser,
                  AST_HTTP_UNKNOWN,
                  status_code,
                  status_title,
                  http_header_data,
                  out,
                  0,
                  0);
}
 
void ast_http_auth(struct ast_tcptls_session_instance *ser, const char *realm,
    const unsigned long nonce, const unsigned long opaque, int stale,
    const char *text)
{
    int status_code = 401;
    char *status_title = "Unauthorized";
    struct ast_str *http_header_data = ast_str_create(DEFAULT_RESPONSE_HEADER_LENGTH);
 
    if (http_header_data) {
        ast_str_set(&http_header_data,
                    0,
                    "WWW-authenticate: Digest algorithm=MD5, realm=\"%s\", nonce=\"%08lx\", qop=\"auth\", opaque=\"%08lx\"%s\r\n"
                    "Content-type: text/html\r\n",
                    realm ? realm : "Asterisk",
                    nonce,
                    opaque,
                    stale ? ", stale=true" : "");
    }
 
    ast_http_create_response(ser,
                             status_code,
                             status_title,
                             http_header_data,
                             text);
}
 
void ast_http_error(struct ast_tcptls_session_instance *ser, int status_code,
    const char *status_title, const char *text)
{
    struct ast_str *http_header_data = ast_str_create(DEFAULT_RESPONSE_HEADER_LENGTH);
 
    if (http_header_data) {
        ast_str_set(&http_header_data, 0, "Content-type: text/html\r\n");
    }
 
    ast_http_create_response(ser,
                             status_code,
                             status_title,
                             http_header_data,
                             text);
}
 
/*!
 * \brief Link the new uri into the list.
 *
 * They are sorted by length of
 * the string, not alphabetically. Duplicate entries are not replaced,
 * but the insertion order (using <= and not just <) makes sure that
 * more recent insertions hide older ones.
 * On a lookup, we just scan the list and stop at the first matching entry.
 */
int ast_http_uri_link(struct ast_http_uri *urih)
{
    struct ast_http_uri *uri;
    int len = strlen(urih->uri);
 
    AST_RWLIST_WRLOCK(&uris);
 
    urih->prefix = prefix;
 
    if ( AST_RWLIST_EMPTY(&uris) || strlen(AST_RWLIST_FIRST(&uris)->uri) <= len ) {
        AST_RWLIST_INSERT_HEAD(&uris, urih, entry);
        AST_RWLIST_UNLOCK(&uris);
        return 0;
    }
 
    AST_RWLIST_TRAVERSE(&uris, uri, entry) {
        if (AST_RWLIST_NEXT(uri, entry) &&
            strlen(AST_RWLIST_NEXT(uri, entry)->uri) <= len) {
            AST_RWLIST_INSERT_AFTER(&uris, uri, urih, entry);
            AST_RWLIST_UNLOCK(&uris);
 
            return 0;
        }
    }
 
    AST_RWLIST_INSERT_TAIL(&uris, urih, entry);
 
    AST_RWLIST_UNLOCK(&uris);
 
    return 0;
}
 
void ast_http_uri_unlink(struct ast_http_uri *urih)
{
    AST_RWLIST_WRLOCK(&uris);
    AST_RWLIST_REMOVE(&uris, urih, entry);
    AST_RWLIST_UNLOCK(&uris);
}
 
void ast_http_uri_unlink_all_with_key(const char *key)
{
    struct ast_http_uri *urih;
    AST_RWLIST_WRLOCK(&uris);
    AST_RWLIST_TRAVERSE_SAFE_BEGIN(&uris, urih, entry) {
        if (!strcmp(urih->key, key)) {
            AST_RWLIST_REMOVE_CURRENT(entry);
            if (urih->dmallocd) {
                ast_free(urih->data);
            }
            if (urih->mallocd) {
                ast_free(urih);
            }
        }
    }
    AST_RWLIST_TRAVERSE_SAFE_END;
    AST_RWLIST_UNLOCK(&uris);
}
 
/*!
 * \brief Retrieves the header with the given field name.
 *
 * \param headers Headers to search.
 * \param field_name Name of the header to find.
 * \return Associated header value.
 * \retval NULL if header is not present.
 */
static const char *get_header(struct ast_variable *headers, const char *field_name)
{
    struct ast_variable *v;
 
    for (v = headers; v; v = v->next) {
        if (!strcasecmp(v->name, field_name)) {
            return v->value;
        }
    }
    return NULL;
}
 
/*!
 * \brief Retrieves the content type specified in the "Content-Type" header.
 *
 * This function only returns the "type/subtype" and any trailing parameter is
 * not included.
 *
 * \note the return value is an allocated string that needs to be freed.
 *
 * \return the content type/subtype
 * \retval NULL if the header is not found.
 */
static char *get_content_type(struct ast_variable *headers)
{
    const char *content_type = get_header(headers, "Content-Type");
    const char *param;
    size_t size;
 
    if (!content_type) {
        return NULL;
    }
 
    param = strchr(content_type, ';');
    size = param ? param - content_type : strlen(content_type);
 
    return ast_strndup(content_type, size);
}
 
/*!
 * \brief Returns the value of the Content-Length header.
 *
 * \param headers HTTP headers.
 *
 * \return length Value of the Content-Length header.
 * \retval 0 if header is not present.
 * \retval -1 if header is invalid.
 */
static int get_content_length(struct ast_variable *headers)
{
    const char *content_length = get_header(headers, "Content-Length");
    int length;
 
    if (!content_length) {
        /* Missing content length; assume zero */
        return 0;
    }
 
    length = 0;
    if (sscanf(content_length, "%30d", &length) != 1) {
        /* Invalid Content-Length value */
        length = -1;
    }
    return length;
}
 
/*!
 * \brief Returns the value of the Transfer-Encoding header.
 *
 * \param headers HTTP headers.
 * \return string Value of the Transfer-Encoding header.
 * \retval NULL if header is not present.
 */
static const char *get_transfer_encoding(struct ast_variable *headers)
{
    return get_header(headers, "Transfer-Encoding");
}
 
/*!
 * \internal
 * \brief Determine if the HTTP peer wants the connection closed.
 *
 * \param headers List of HTTP headers
 *
 * \retval 0 keep connection open.
 * \retval -1 close connection.
 */
static int http_check_connection_close(struct ast_variable *headers)
{
    const char *connection = get_header(headers, "Connection");
    int close_connection = 0;
 
    if (connection && !strcasecmp(connection, "close")) {
        close_connection = -1;
    }
    return close_connection;
}
 
void ast_http_request_close_on_completion(struct ast_tcptls_session_instance *ser)
{
    struct http_worker_private_data *request = ser->private_data;
 
    ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
}
 
/*!
 * \internal
 * \brief Initialize the request tracking information in case of early failure.
 * \since 12.4.0
 *
 * \param request Request tracking information.
 */
static void http_request_tracking_init(struct http_worker_private_data *request)
{
    ast_set_flags_to(&request->flags,
        HTTP_FLAG_HAS_BODY | HTTP_FLAG_BODY_READ | HTTP_FLAG_CLOSE_ON_COMPLETION,
        /* Assume close in case request fails early */
        HTTP_FLAG_CLOSE_ON_COMPLETION);
}
 
/*!
 * \internal
 * \brief Setup the HTTP request tracking information.
 * \since 12.4.0
 *
 * \param ser HTTP TCP/TLS session object.
 * \param headers List of HTTP headers.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int http_request_tracking_setup(struct ast_tcptls_session_instance *ser, struct ast_variable *headers)
{
    struct http_worker_private_data *request = ser->private_data;
    const char *transfer_encoding;
 
    ast_set_flags_to(&request->flags,
        HTTP_FLAG_HAS_BODY | HTTP_FLAG_BODY_READ | HTTP_FLAG_CLOSE_ON_COMPLETION,
        http_check_connection_close(headers) ? HTTP_FLAG_CLOSE_ON_COMPLETION : 0);
 
    transfer_encoding = get_transfer_encoding(headers);
    if (transfer_encoding && !strcasecmp(transfer_encoding, "chunked")) {
        request->body_length = -1;
        ast_set_flag(&request->flags, HTTP_FLAG_HAS_BODY);
        return 0;
    }
 
    request->body_length = get_content_length(headers);
    if (0 < request->body_length) {
        ast_set_flag(&request->flags, HTTP_FLAG_HAS_BODY);
    } else if (request->body_length < 0) {
        /* Invalid Content-Length */
        ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
        ast_http_error(ser, 400, "Bad Request", "Invalid Content-Length in request!");
        return -1;
    }
    return 0;
}
 
void ast_http_body_read_status(struct ast_tcptls_session_instance *ser, int read_success)
{
    struct http_worker_private_data *request;
 
    request = ser->private_data;
    if (!ast_test_flag(&request->flags, HTTP_FLAG_HAS_BODY)
        || ast_test_flag(&request->flags, HTTP_FLAG_BODY_READ)) {
        /* No body to read. */
        return;
    }
    ast_set_flag(&request->flags, HTTP_FLAG_BODY_READ);
    if (!read_success) {
        ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
    }
}
 
/*!
 * \internal
 * \brief Read the next length bytes from the HTTP body.
 * \since 12.4.0
 *
 * \param ser HTTP TCP/TLS session object.
 * \param buf Where to put the contents reading.
 * \param length How much contents to read.
 * \param what_getting Name of the contents reading.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int http_body_read_contents(struct ast_tcptls_session_instance *ser, char *buf, int length, const char *what_getting)
{
    int res;
    int total = 0;
 
    /* Stream is in exclusive mode so we get it all if possible. */
    while (total != length) {
        res = ast_iostream_read(ser->stream, buf + total, length - total);
        if (res <= 0) {
            break;
        }
 
        total += res;
    }
 
    if (total != length) {
        ast_log(LOG_WARNING, "Wrong HTTP content read. Request %s (Wanted %d, Read %d)\n",
            what_getting, length, res);
        return -1;
    }
 
    return 0;
}
 
/*!
 * \internal
 * \brief Read and discard the next length bytes from the HTTP body.
 * \since 12.4.0
 *
 * \param ser HTTP TCP/TLS session object.
 * \param length How much contents to discard
 * \param what_getting Name of the contents discarding.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int http_body_discard_contents(struct ast_tcptls_session_instance *ser, int length, const char *what_getting)
{
    ssize_t res;
 
    res = ast_iostream_discard(ser->stream, length);
    if (res < length) {
        ast_log(LOG_WARNING, "Short HTTP request %s (Wanted %d but got %zd)\n",
            what_getting, length, res);
        return -1;
    }
    return 0;
}
 
/*!
 * \internal
 * \brief decode chunked mode hexadecimal value
 *
 * \param s string to decode
 * \param len length of string
 *
 * \return length on success.
 * \retval -1 on error.
 */
static int chunked_atoh(const char *s, int len)
{
    int value = 0;
    char c;
 
    if (*s < '0') {
        /* zero value must be 0\n not just \n */
        return -1;
    }
 
    while (len--) {
        c = *s++;
        if (c == '\x0D') {
            return value;
        }
        if (c == ';') {
            /* We have a chunk-extension that we don't care about. */
            while (len--) {
                if (*s++ == '\x0D') {
                    return value;
                }
            }
            break;
        }
        value <<= 4;
        if (c >= '0' && c <= '9') {
            value += c - '0';
            continue;
        }
        if (c >= 'a' && c <= 'f') {
            value += 10 + c - 'a';
            continue;
        }
        if (c >= 'A' && c <= 'F') {
            value += 10 + c - 'A';
            continue;
        }
        /* invalid character */
        return -1;
    }
    /* end of string */
    return -1;
}
 
/*!
 * \internal
 * \brief Read and convert the chunked body header length.
 * \since 12.4.0
 *
 * \param ser HTTP TCP/TLS session object.
 *
 * \return length Size of chunk to expect.
 * \retval -1 on error.
 */
static int http_body_get_chunk_length(struct ast_tcptls_session_instance *ser)
{
    int length;
    char header_line[MAX_HTTP_LINE_LENGTH];
 
    /* get the line of hexadecimal giving chunk-size w/ optional chunk-extension */
    if (ast_iostream_gets(ser->stream, header_line, sizeof(header_line)) <= 0) {
        ast_log(LOG_WARNING, "Short HTTP read of chunked header\n");
        return -1;
    }
    length = chunked_atoh(header_line, strlen(header_line));
    if (length < 0) {
        ast_log(LOG_WARNING, "Invalid HTTP chunk size\n");
        return -1;
    }
    return length;
}
 
/*!
 * \internal
 * \brief Read and check the chunk contents line termination.
 * \since 12.4.0
 *
 * \param ser HTTP TCP/TLS session object.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int http_body_check_chunk_sync(struct ast_tcptls_session_instance *ser)
{
    int res;
    char chunk_sync[2];
 
    /* Stay in fread until get the expected CRLF or timeout. */
    res = ast_iostream_read(ser->stream, chunk_sync, sizeof(chunk_sync));
    if (res < sizeof(chunk_sync)) {
        ast_log(LOG_WARNING, "Short HTTP chunk sync read (Wanted %zu)\n",
            sizeof(chunk_sync));
        return -1;
    }
    if (chunk_sync[0] != 0x0D || chunk_sync[1] != 0x0A) {
        ast_log(LOG_WARNING, "HTTP chunk sync bytes wrong (0x%02hhX, 0x%02hhX)\n",
            (unsigned char) chunk_sync[0], (unsigned char) chunk_sync[1]);
        return -1;
    }
 
    return 0;
}
 
/*!
 * \internal
 * \brief Read and discard any chunked trailer entity-header lines.
 * \since 12.4.0
 *
 * \param ser HTTP TCP/TLS session object.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int http_body_discard_chunk_trailer_headers(struct ast_tcptls_session_instance *ser)
{
    char header_line[MAX_HTTP_LINE_LENGTH];
 
    for (;;) {
        if (ast_iostream_gets(ser->stream, header_line, sizeof(header_line)) <= 0) {
            ast_log(LOG_WARNING, "Short HTTP read of chunked trailer header\n");
            return -1;
        }
 
        /* Trim trailing whitespace */
        ast_trim_blanks(header_line);
        if (ast_strlen_zero(header_line)) {
            /* A blank line ends the chunked-body */
            break;
        }
    }
    return 0;
}
 
int ast_http_body_discard(struct ast_tcptls_session_instance *ser)
{
    struct http_worker_private_data *request;
 
    request = ser->private_data;
    if (!ast_test_flag(&request->flags, HTTP_FLAG_HAS_BODY)
        || ast_test_flag(&request->flags, HTTP_FLAG_BODY_READ)) {
        /* No body to read or it has already been read. */
        return 0;
    }
    ast_set_flag(&request->flags, HTTP_FLAG_BODY_READ);
 
    ast_debug(1, "HTTP discarding unused request body\n");
 
    ast_assert(request->body_length != 0);
    if (0 < request->body_length) {
        if (http_body_discard_contents(ser, request->body_length, "body")) {
            ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
            return -1;
        }
        return 0;
    }
 
    /* parse chunked-body */
    for (;;) {
        int length;
 
        length = http_body_get_chunk_length(ser);
        if (length < 0) {
            ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
            return -1;
        }
        if (length == 0) {
            /* parsed last-chunk */
            break;
        }
 
        if (http_body_discard_contents(ser, length, "chunk-data")
            || http_body_check_chunk_sync(ser)) {
            ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
            return -1;
        }
    }
 
    /* Read and discard any trailer entity-header lines. */
    if (http_body_discard_chunk_trailer_headers(ser)) {
        ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
        return -1;
    }
    return 0;
}
 
/*!
 * \brief Returns the contents (body) of the HTTP request
 *
 * \param return_length ptr to int that returns content length
 * \param ser HTTP TCP/TLS session object
 * \param headers List of HTTP headers
 * \return ptr to content (zero terminated)
 * \retval NULL on failure
 * \note Since returned ptr is malloc'd, it should be free'd by caller
 */
static char *ast_http_get_contents(int *return_length,
    struct ast_tcptls_session_instance *ser, struct ast_variable *headers)
{
    struct http_worker_private_data *request;
    int content_length;
    int bufsize;
    char *buf;
 
    request = ser->private_data;
    if (!ast_test_flag(&request->flags, HTTP_FLAG_HAS_BODY)) {
        /* no content - not an error */
        return NULL;
    }
    if (ast_test_flag(&request->flags, HTTP_FLAG_BODY_READ)) {
        /* Already read the body.  Cannot read again.  Assume no content. */
        ast_assert(0);
        return NULL;
    }
    ast_set_flag(&request->flags, HTTP_FLAG_BODY_READ);
 
    ast_debug(2, "HTTP consuming request body\n");
 
    ast_assert(request->body_length != 0);
    if (0 < request->body_length) {
        /* handle regular non-chunked content */
        content_length = request->body_length;
        if (content_length > MAX_CONTENT_LENGTH) {
            ast_log(LOG_WARNING, "Excessively long HTTP content. (%d > %d)\n",
                content_length, MAX_CONTENT_LENGTH);
            ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
            errno = EFBIG;
            return NULL;
        }
        buf = ast_malloc(content_length + 1);
        if (!buf) {
            /* Malloc sets ENOMEM */
            ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
            return NULL;
        }
 
        if (http_body_read_contents(ser, buf, content_length, "body")) {
            ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
            errno = EIO;
            ast_free(buf);
            return NULL;
        }
 
        buf[content_length] = 0;
        *return_length = content_length;
        return buf;
    }
 
    /* pre-allocate buffer */
    bufsize = 250;
    buf = ast_malloc(bufsize);
    if (!buf) {
        ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
        return NULL;
    }
 
    /* parse chunked-body */
    content_length = 0;
    for (;;) {
        int chunk_length;
 
        chunk_length = http_body_get_chunk_length(ser);
        if (chunk_length < 0) {
            ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
            errno = EIO;
            ast_free(buf);
            return NULL;
        }
        if (chunk_length == 0) {
            /* parsed last-chunk */
            break;
        }
        if (content_length + chunk_length > MAX_CONTENT_LENGTH) {
            ast_log(LOG_WARNING,
                "Excessively long HTTP accumulated chunked body. (%d + %d > %d)\n",
                content_length, chunk_length, MAX_CONTENT_LENGTH);
            ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
            errno = EFBIG;
            ast_free(buf);
            return NULL;
        }
 
        /* insure buffer is large enough +1 */
        if (content_length + chunk_length >= bufsize) {
            char *new_buf;
 
            /* Increase bufsize until it can handle the expected data. */
            do {
                bufsize *= 2;
            } while (content_length + chunk_length >= bufsize);
 
            new_buf = ast_realloc(buf, bufsize);
            if (!new_buf) {
                ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
                ast_free(buf);
                return NULL;
            }
            buf = new_buf;
        }
 
        if (http_body_read_contents(ser, buf + content_length, chunk_length, "chunk-data")
            || http_body_check_chunk_sync(ser)) {
            ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
            errno = EIO;
            ast_free(buf);
            return NULL;
        }
        content_length += chunk_length;
    }
 
    /*
     * Read and discard any trailer entity-header lines
     * which we don't care about.
     *
     * XXX In the future we may need to add the trailer headers
     * to the passed in headers list rather than discarding them.
     */
    if (http_body_discard_chunk_trailer_headers(ser)) {
        ast_set_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION);
        errno = EIO;
        ast_free(buf);
        return NULL;
    }
 
    buf[content_length] = 0;
    *return_length = content_length;
    return buf;
}
 
struct ast_json *ast_http_get_json(
    struct ast_tcptls_session_instance *ser, struct ast_variable *headers)
{
    int content_length = 0;
    struct ast_json *body;
    RAII_VAR(char *, buf, NULL, ast_free);
    RAII_VAR(char *, type, get_content_type(headers), ast_free);
 
    /* Use errno to distinguish errors from no body */
    errno = 0;
 
    if (ast_strlen_zero(type) || strcasecmp(type, "application/json")) {
        /* Content type is not JSON.  Don't read the body. */
        return NULL;
    }
 
    buf = ast_http_get_contents(&content_length, ser, headers);
    if (!buf || !content_length) {
        /*
         * errno already set
         * or it is not an error to have zero content
         */
        return NULL;
    }
 
    body = ast_json_load_buf(buf, content_length, NULL);
    if (!body) {
        /* Failed to parse JSON; treat as an I/O error */
        errno = EIO;
        return NULL;
    }
 
    return body;
}
 
/*
 * get post variables from client Request Entity-Body, if content type is
 * application/x-www-form-urlencoded
 */
struct ast_variable *ast_http_parse_post_form(char *buf, int content_length,
    const char *content_type)
{
    struct ast_variable *v, *post_vars=NULL, *prev = NULL;
    char *var, *val;
 
    /* Use errno to distinguish errors from no params */
    errno = 0;
 
    if (ast_strlen_zero(content_type) ||
        strcasecmp(content_type, "application/x-www-form-urlencoded") != 0) {
        /* Content type is not form data.  Don't read the body. */
        return NULL;
    }
 
    while ((val = strsep(&buf, "&"))) {
        var = strsep(&val, "=");
        if (val) {
            ast_uri_decode(val, ast_uri_http_legacy);
        } else  {
            val = "";
        }
        ast_uri_decode(var, ast_uri_http_legacy);
        if ((v = ast_variable_new(var, val, ""))) {
            if (post_vars) {
                prev->next = v;
            } else {
                post_vars = v;
            }
            prev = v;
        }
    }
 
    return post_vars;
}
 
struct ast_variable *ast_http_get_post_vars(
    struct ast_tcptls_session_instance *ser, struct ast_variable *headers)
{
    int content_length = 0;
    RAII_VAR(char *, buf, NULL, ast_free);
    RAII_VAR(char *, type, get_content_type(headers), ast_free);
 
    /* Use errno to distinguish errors from no params */
    errno = 0;
 
    if (ast_strlen_zero(type) ||
        strcasecmp(type, "application/x-www-form-urlencoded")) {
        /* Content type is not form data.  Don't read the body. */
        return NULL;
    }
 
    buf = ast_http_get_contents(&content_length, ser, headers);
    if (!buf || !content_length) {
        /*
         * errno already set
         * or it is not an error to have zero content
         */
        return NULL;
    }
 
    return ast_http_parse_post_form(buf, content_length, type);
}
 
static int handle_uri(struct ast_tcptls_session_instance *ser, char *uri,
    enum ast_http_method method, struct ast_variable *headers)
{
    char *c;
    int res = 0;
    char *params = uri;
    struct ast_http_uri *urih = NULL;
    int l;
    struct ast_variable *get_vars = NULL, *v, *prev = NULL;
    struct http_uri_redirect *redirect;
 
    ast_debug(2, "HTTP Request URI is %s \n", uri);
 
    strsep(&params, "?");
    /* Extract arguments from the request and store them in variables. */
    if (params) {
        char *var, *val;
 
        while ((val = strsep(&params, "&"))) {
            var = strsep(&val, "=");
            if (val) {
                ast_uri_decode(val, ast_uri_http_legacy);
            } else  {
                val = "";
            }
            ast_uri_decode(var, ast_uri_http_legacy);
            if ((v = ast_variable_new(var, val, ""))) {
                if (get_vars) {
                    prev->next = v;
                } else {
                    get_vars = v;
                }
                prev = v;
            }
        }
    }
 
    /* Check path-based ACL restrictions */
    if (check_restriction_acl(ser, uri) != 0) {
        ast_http_request_close_on_completion(ser);
        ast_http_error(ser, 403, "Forbidden", "Access denied by ACL");
        goto cleanup;
    }
 
    AST_RWLIST_RDLOCK(&uri_redirects);
    AST_RWLIST_TRAVERSE(&uri_redirects, redirect, entry) {
        if (!strcasecmp(uri, redirect->target)) {
            struct ast_str *http_header = ast_str_create(128);
 
            if (!http_header) {
                ast_http_request_close_on_completion(ser);
                ast_http_error(ser, 500, "Server Error", "Out of memory");
                break;
            }
            ast_str_set(&http_header, 0, "Location: %s\r\n", redirect->dest);
            ast_http_send(ser, method, 302, "Moved Temporarily", http_header, NULL, 0, 0);
            break;
        }
    }
    AST_RWLIST_UNLOCK(&uri_redirects);
    if (redirect) {
        goto cleanup;
    }
 
    /* We want requests to start with the (optional) prefix and '/' */
    l = strlen(prefix);
    if (!strncasecmp(uri, prefix, l) && uri[l] == '/') {
        uri += l + 1;
        /* scan registered uris to see if we match one. */
        AST_RWLIST_RDLOCK(&uris);
        AST_RWLIST_TRAVERSE(&uris, urih, entry) {
            l = strlen(urih->uri);
            c = uri + l;    /* candidate */
            ast_debug(2, "match request [%s] with handler [%s] len %d\n", uri, urih->uri, l);
            if (strncasecmp(urih->uri, uri, l) /* no match */
                || (*c && *c != '/')) { /* substring */
                continue;
            }
            if (*c == '/') {
                c++;
            }
            if (!*c || urih->has_subtree) {
                uri = c;
                break;
            }
        }
        AST_RWLIST_UNLOCK(&uris);
    }
    if (urih) {
        ast_debug(1, "Match made with [%s]\n", urih->uri);
        if (!urih->no_decode_uri) {
            ast_uri_decode(uri, ast_uri_http_legacy);
        }
        res = urih->callback(ser, urih, uri, method, get_vars, headers);
    } else {
        ast_debug(1, "Request from %s for URI [%s] has no registered handler\n",
            ast_sockaddr_stringify_addr(&ser->remote_address), uri);
        ast_http_error(ser, 404, "Not Found", "The requested URL was not found on this server.");
    }
 
cleanup:
    ast_variables_destroy(get_vars);
    return res;
}
 
static struct ast_variable *parse_cookies(const char *cookies)
{
    char *parse = ast_strdupa(cookies);
    char *cur;
    struct ast_variable *vars = NULL, *var;
 
    while ((cur = strsep(&parse, ";"))) {
        char *name, *val;
 
        name = val = cur;
        strsep(&val, "=");
 
        if (ast_strlen_zero(name) || ast_strlen_zero(val)) {
            continue;
        }
 
        name = ast_strip(name);
        val = ast_strip_quoted(val, "\"", "\"");
 
        if (ast_strlen_zero(name) || ast_strlen_zero(val)) {
            continue;
        }
 
        ast_debug(1, "HTTP Cookie, Name: '%s'  Value: '%s'\n", name, val);
 
        var = ast_variable_new(name, val, __FILE__);
        var->next = vars;
        vars = var;
    }
 
    return vars;
}
 
/* get cookie from Request headers */
struct ast_variable *ast_http_get_cookies(struct ast_variable *headers)
{
    struct ast_variable *v, *cookies = NULL;
 
    for (v = headers; v; v = v->next) {
        if (!strcasecmp(v->name, "Cookie")) {
            ast_variables_destroy(cookies);
            cookies = parse_cookies(v->value);
        }
    }
    return cookies;
}
 
static struct ast_http_auth *auth_create(const char *userid, const char *password)
{
    struct ast_http_auth *auth;
    size_t userid_len;
    size_t password_len;
 
    if (!userid || !password) {
        ast_log(LOG_ERROR, "Invalid userid/password\n");
        return NULL;
    }
 
    userid_len = strlen(userid) + 1;
    password_len = strlen(password) + 1;
 
    /* Allocate enough room to store everything in one memory block */
    auth = ao2_alloc(sizeof(*auth) + userid_len + password_len, NULL);
    if (!auth) {
        return NULL;
    }
 
    /* Put the userid right after the struct */
    auth->userid = (char *)(auth + 1);
    strcpy(auth->userid, userid);
 
    /* Put the password right after the userid */
    auth->password = auth->userid + userid_len;
    strcpy(auth->password, password);
 
    return auth;
}
 
#define BASIC_PREFIX "Basic "
#define BASIC_LEN 6 /*!< strlen(BASIC_PREFIX) */
 
struct ast_http_auth *ast_http_get_auth(struct ast_variable *headers)
{
    struct ast_variable *v;
 
    for (v = headers; v; v = v->next) {
        const char *base64;
        char decoded[256] = {};
        char *username;
        char *password;
#ifdef AST_DEVMODE
        int cnt;
#endif /* AST_DEVMODE */
 
        if (strcasecmp("Authorization", v->name) != 0) {
            continue;
        }
 
        if (!ast_begins_with(v->value, BASIC_PREFIX)) {
            ast_log(LOG_DEBUG,
                "Unsupported Authorization scheme\n");
            continue;
        }
 
        /* Basic auth header parsing. RFC 2617, section 2.
         *   credentials = "Basic" basic-credentials
         *   basic-credentials = base64-user-pass
         *   base64-user-pass  = <base64 encoding of user-pass,
         *                        except not limited to 76 char/line>
         *   user-pass   = userid ":" password
         */
 
        base64 = v->value + BASIC_LEN;
 
        /* This will truncate "userid:password" lines to
         * sizeof(decoded). The array is long enough that this shouldn't
         * be a problem */
#ifdef AST_DEVMODE
        cnt =
#endif /* AST_DEVMODE */
        ast_base64decode((unsigned char*)decoded, base64,
            sizeof(decoded) - 1);
        ast_assert(cnt < sizeof(decoded));
 
        /* Split the string at the colon */
        password = decoded;
        username = strsep(&password, ":");
        if (!password) {
            ast_log(LOG_WARNING, "Invalid Authorization header\n");
            return NULL;
        }
 
        return auth_create(username, password);
    }
 
    return NULL;
}
 
struct ast_variable *ast_http_create_basic_auth_header(const char *userid,
    const char *password)
{
    int encoded_size = 0;
    int userinfo_len = 0;
    RAII_VAR(char *, userinfo, NULL, ast_free);
    char *encoded_userinfo = NULL;
    struct ast_variable *auth_header = NULL;
 
    if (ast_strlen_zero(userid)) {
        return NULL;
    }
 
    if (strchr(userid, ':')) {
        userinfo = ast_strdup(userid);
        userinfo_len = strlen(userinfo);
    } else {
        if (ast_strlen_zero(password)) {
            return NULL;
        }
        userinfo_len = ast_asprintf(&userinfo, "%s:%s", userid, password);
    }
    if (!userinfo) {
        return NULL;
    }
 
    /*
     * The header value is "Basic " + base64(userinfo).
     * Doubling the userinfo length then adding the length
     * of the "Basic " prefix is a conservative estimate of the
     * final encoded size.
     */
    encoded_size = userinfo_len * 2 * sizeof(char) + 1 + BASIC_LEN;
    encoded_userinfo = ast_alloca(encoded_size);
    strcpy(encoded_userinfo, BASIC_PREFIX); /* Safe */
    ast_base64encode(encoded_userinfo + BASIC_LEN, (unsigned char *)userinfo,
        userinfo_len, encoded_size - BASIC_LEN);
 
    auth_header = ast_variable_new("Authorization",
        encoded_userinfo, "");
 
    return auth_header;
}
 
int ast_http_response_status_line(const char *buf, const char *version, int code)
{
    int status_code;
    size_t size = strlen(version);
 
    if (strncmp(buf, version, size) || buf[size] != ' ') {
        ast_log(LOG_ERROR, "HTTP version not supported - "
            "expected %s\n", version);
        return -1;
    }
 
    /* skip to status code (version + space) */
    buf += size + 1;
 
    if (sscanf(buf, "%d", &status_code) != 1) {
        ast_log(LOG_ERROR, "Could not read HTTP status code - "
            "%s\n", buf);
        return -1;
    }
 
    return status_code;
}
 
static void remove_excess_lws(char *s)
{
    char *p, *res = s;
    char *buf = ast_malloc(strlen(s) + 1);
    char *buf_end;
 
    if (!buf) {
        return;
    }
 
    buf_end = buf;
 
    while (*s && *(s = ast_skip_blanks(s))) {
        p = s;
        s = ast_skip_nonblanks(s);
 
        if (buf_end != buf) {
            *buf_end++ = ' ';
        }
 
        memcpy(buf_end, p, s - p);
        buf_end += s - p;
    }
    *buf_end = '\0';
    /* safe since buf will always be less than or equal to res */
    strcpy(res, buf);
    ast_free(buf);
}
 
int ast_http_header_parse(char *buf, char **name, char **value)
{
    ast_trim_blanks(buf);
    if (ast_strlen_zero(buf)) {
        return -1;
    }
 
    *value = buf;
    *name = strsep(value, ":");
    if (!*value) {
        return 1;
    }
 
    *value = ast_skip_blanks(*value);
    if (ast_strlen_zero(*value) || ast_strlen_zero(*name)) {
        return 1;
    }
 
    remove_excess_lws(*value);
    return 0;
}
 
int ast_http_header_match(const char *name, const char *expected_name,
              const char *value, const char *expected_value)
{
    if (strcasecmp(name, expected_name)) {
        /* no value to validate if names don't match */
        return 0;
    }
 
    if (strcasecmp(value, expected_value)) {
        ast_log(LOG_ERROR, "Invalid header value - expected %s "
            "received %s", value, expected_value);
        return -1;
    }
    return 1;
}
 
int ast_http_header_match_in(const char *name, const char *expected_name,
                 const char *value, const char *expected_value)
{
    if (strcasecmp(name, expected_name)) {
        /* no value to validate if names don't match */
        return 0;
    }
 
    if (!strcasestr(expected_value, value)) {
        ast_log(LOG_ERROR, "Header '%s' - could not locate '%s' "
            "in '%s'\n", name, value, expected_value);
        return -1;
 
    }
    return 1;
}
 
/*! Limit the number of request headers in case the sender is being ridiculous. */
#define MAX_HTTP_REQUEST_HEADERS    100
 
/*!
 * \internal
 * \brief Read the request headers.
 * \since 12.4.0
 *
 * \param ser HTTP TCP/TLS session object.
 * \param headers Where to put the request headers list pointer.
 *
 * \retval 0 on success.
 * \retval -1 on error.
 */
static int http_request_headers_get(struct ast_tcptls_session_instance *ser, struct ast_variable **headers)
{
    struct ast_variable *tail = *headers;
    int remaining_headers;
    char header_line[MAX_HTTP_LINE_LENGTH];
 
    remaining_headers = MAX_HTTP_REQUEST_HEADERS;
    for (;;) {
        ssize_t len;
        char *name;
        char *value;
 
        len = ast_iostream_gets(ser->stream, header_line, sizeof(header_line));
        if (len <= 0) {
            ast_http_error(ser, 400, "Bad Request", "Timeout");
            return -1;
        }
        if (header_line[len - 1] != '\n') {
            /* We didn't get a full line */
            ast_http_error(ser, 400, "Bad Request",
                (len == sizeof(header_line) - 1) ? "Header line too long" : "Timeout");
            return -1;
        }
 
        /* Trim trailing characters */
        ast_trim_blanks(header_line);
        if (ast_strlen_zero(header_line)) {
            /* A blank line ends the request header section. */
            break;
        }
 
        value = header_line;
        name = strsep(&value, ":");
        if (!value) {
            continue;
        }
 
        value = ast_skip_blanks(value);
        if (ast_strlen_zero(value) || ast_strlen_zero(name)) {
            continue;
        }
 
        ast_trim_blanks(name);
 
        if (!remaining_headers--) {
            /* Too many headers. */
            ast_http_error(ser, 413, "Request Entity Too Large", "Too many headers");
            return -1;
        }
        if (!*headers) {
            *headers = ast_variable_new(name, value, __FILE__);
            tail = *headers;
        } else {
            tail->next = ast_variable_new(name, value, __FILE__);
            tail = tail->next;
        }
        if (!tail) {
            /*
             * Variable allocation failure.
             * Try to make some room.
             */
            ast_variables_destroy(*headers);
            *headers = NULL;
 
            ast_http_error(ser, 500, "Server Error", "Out of memory");
            return -1;
        }
    }
 
    return 0;
}
 
/*!
 * \internal
 * \brief Process a HTTP request.
 * \since 12.4.0
 *
 * \param ser HTTP TCP/TLS session object.
 *
 * \retval 0 Continue and process the next HTTP request.
 * \retval -1 Fatal HTTP connection error.  Force the HTTP connection closed.
 */
static int httpd_process_request(struct ast_tcptls_session_instance *ser)
{
    RAII_VAR(struct ast_variable *, headers, NULL, ast_variables_destroy);
    char *uri;
    char *method;
    const char *transfer_encoding;
    struct http_worker_private_data *request;
    enum ast_http_method http_method = AST_HTTP_UNKNOWN;
    int res;
    ssize_t len;
    char request_line[MAX_HTTP_LINE_LENGTH];
 
    len = ast_iostream_gets(ser->stream, request_line, sizeof(request_line));
    if (len <= 0) {
        return -1;
    }
 
    /* Re-initialize the request body tracking data. */
    request = ser->private_data;
    http_request_tracking_init(request);
 
    if (request_line[len - 1] != '\n') {
        /* We didn't get a full line */
        ast_http_error(ser, 400, "Bad Request",
            (len == sizeof(request_line) - 1) ? "Request line too long" : "Timeout");
        return -1;
    }
 
    /* Get method */
    method = ast_skip_blanks(request_line);
    uri = ast_skip_nonblanks(method);
    if (*uri) {
        *uri++ = '\0';
    }
 
    if (!strcasecmp(method,"GET")) {
        http_method = AST_HTTP_GET;
    } else if (!strcasecmp(method,"POST")) {
        http_method = AST_HTTP_POST;
    } else if (!strcasecmp(method,"HEAD")) {
        http_method = AST_HTTP_HEAD;
    } else if (!strcasecmp(method,"PUT")) {
        http_method = AST_HTTP_PUT;
    } else if (!strcasecmp(method,"DELETE")) {
        http_method = AST_HTTP_DELETE;
    } else if (!strcasecmp(method,"OPTIONS")) {
        http_method = AST_HTTP_OPTIONS;
    }
 
    uri = ast_skip_blanks(uri); /* Skip white space */
    if (*uri) {         /* terminate at the first blank */
        char *c = ast_skip_nonblanks(uri);
 
        if (*c) {
            *c = '\0';
        }
    } else {
        ast_http_error(ser, 400, "Bad Request", "Invalid Request");
        return -1;
    }
 
    if (ast_shutdown_final()) {
        ast_http_error(ser, 503, "Service Unavailable", "Shutdown in progress");
        return -1;
    }
 
    /* process "Request Headers" lines */
    if (http_request_headers_get(ser, &headers)) {
        return -1;
    }
 
    transfer_encoding = get_transfer_encoding(headers);
    /* Transfer encoding defaults to identity */
    if (!transfer_encoding) {
        transfer_encoding = "identity";
    }
 
    /*
     * RFC 2616, section 3.6, we should respond with a 501 for any transfer-
     * codings we don't understand.
     */
    if (strcasecmp(transfer_encoding, "identity") != 0 &&
        strcasecmp(transfer_encoding, "chunked") != 0) {
        /* Transfer encodings not supported */
        ast_http_error(ser, 501, "Unimplemented", "Unsupported Transfer-Encoding.");
        return -1;
    }
 
    if (http_request_tracking_setup(ser, headers)
        || handle_uri(ser, uri, http_method, headers)
        || ast_test_flag(&request->flags, HTTP_FLAG_CLOSE_ON_COMPLETION)) {
        res = -1;
    } else {
        res = 0;
    }
    return res;
}
 
static void *httpd_helper_thread(void *data)
{
    struct ast_tcptls_session_instance *ser = data;
    int timeout;
    int arg = 1;
 
    if (!ser) {
        ao2_cleanup(ser);
        return NULL;
    }
 
    if (ast_atomic_fetchadd_int(&session_count, +1) >= session_limit) {
        ast_log(LOG_WARNING, "HTTP session count exceeded %d sessions.\n",
            session_limit);
        goto done;
    }
    ast_debug(1, "HTTP opening session.  Top level\n");
 
    /*
     * Here we set TCP_NODELAY on the socket to disable Nagle's algorithm.
     * This is necessary to prevent delays (caused by buffering) as we
     * write to the socket in bits and pieces.
     */
    if (setsockopt(ast_iostream_get_fd(ser->stream), IPPROTO_TCP, TCP_NODELAY, (char *) &arg, sizeof(arg)) < 0) {
        ast_log(LOG_WARNING, "Failed to set TCP_NODELAY on HTTP connection: %s\n", strerror(errno));
    }
    ast_iostream_nonblock(ser->stream);
 
    /* Setup HTTP worker private data to keep track of request body reading. */
    ao2_cleanup(ser->private_data);
    ser->private_data = ao2_alloc_options(sizeof(struct http_worker_private_data), NULL,
        AO2_ALLOC_OPT_LOCK_NOLOCK);
    if (!ser->private_data) {
        ast_http_error(ser, 500, "Server Error", "Out of memory");
        goto done;
    }
    http_request_tracking_init(ser->private_data);
 
    /* Determine initial HTTP request wait timeout. */
    timeout = session_keep_alive;
    if (timeout <= 0) {
        /* Persistent connections not enabled. */
        timeout = session_inactivity;
    }
    if (timeout < MIN_INITIAL_REQUEST_TIMEOUT) {
        timeout = MIN_INITIAL_REQUEST_TIMEOUT;
    }
 
    /* We can let the stream wait for data to arrive. */
    ast_iostream_set_exclusive_input(ser->stream, 1);
 
    for (;;) {
        /* Wait for next potential HTTP request message. */
        ast_iostream_set_timeout_idle_inactivity(ser->stream, timeout, session_inactivity);
        if (httpd_process_request(ser)) {
            /* Break the connection or the connection closed */
            break;
        }
        if (!ser->stream) {
            /* Web-socket or similar that took the connection */
            break;
        }
 
        timeout = session_keep_alive;
        if (timeout <= 0) {
            /* Persistent connections not enabled. */
            break;
        }
    }
 
done:
    ast_atomic_fetchadd_int(&session_count, -1);
 
    ast_debug(1, "HTTP closing session.  Top level\n");
    ast_tcptls_close_session_file(ser);
 
    ao2_ref(ser, -1);
    return NULL;
}
 
/*!
 * \brief Check if a URI path is allowed or denied by acl
 * \param ser TCP/TLS session instance
 * \param uri The URI path to check
 * \return 0 if allowed, -1 if denied
 */
static int check_restriction_acl(struct ast_tcptls_session_instance *ser, const char *uri)
{
    struct http_restriction *restriction;
    int denied = 0;
 
    AST_RWLIST_RDLOCK(&restrictions);
    AST_RWLIST_TRAVERSE(&restrictions, restriction, entry) {
        if (ast_begins_with(uri, restriction->path)) {
            if (restriction->acl && !ast_acl_list_is_empty(restriction->acl)) {
                if (ast_apply_acl(restriction->acl, &ser->remote_address,
                    "HTTP Path ACL") == AST_SENSE_DENY) {
                    ast_debug(2, "HTTP request for uri '%s' from %s denied by acl by restriction on '%s'\n",
                        uri, ast_sockaddr_stringify(&ser->remote_address), restriction->path);
                    denied = -1;
                    break;
                }
            }
        }
    }
    AST_RWLIST_UNLOCK(&restrictions);
 
    return denied;
}
 
/*!
 * \brief Add a new URI redirect
 * The entries in the redirect list are sorted by length, just like the list
 * of URI handlers.
 */
static void add_redirect(const char *value)
{
    char *target, *dest;
    struct http_uri_redirect *redirect, *cur;
    unsigned int target_len;
    unsigned int total_len;
    size_t dest_len;
 
    dest = ast_strdupa(value);
    dest = ast_skip_blanks(dest);
    target = strsep(&dest, " ");
    target = ast_skip_blanks(target);
    target = strsep(&target, " "); /* trim trailing whitespace */
 
    if (!dest) {
        ast_log(LOG_WARNING, "Invalid redirect '%s'\n", value);
        return;
    }
 
    target_len = strlen(target) + 1;
    dest_len = strlen(dest) + 1;
    total_len = sizeof(*redirect) + target_len + dest_len;
 
    if (!(redirect = ast_calloc(1, total_len))) {
        return;
    }
    redirect->dest = redirect->target + target_len;
    strcpy(redirect->target, target);
    ast_copy_string(redirect->dest, dest, dest_len);
 
    AST_RWLIST_WRLOCK(&uri_redirects);
 
    target_len--; /* So we can compare directly with strlen() */
    if (AST_RWLIST_EMPTY(&uri_redirects)
        || strlen(AST_RWLIST_FIRST(&uri_redirects)->target) <= target_len ) {
        AST_RWLIST_INSERT_HEAD(&uri_redirects, redirect, entry);
        AST_RWLIST_UNLOCK(&uri_redirects);
 
        return;
    }
 
    AST_RWLIST_TRAVERSE(&uri_redirects, cur, entry) {
        if (AST_RWLIST_NEXT(cur, entry)
            && strlen(AST_RWLIST_NEXT(cur, entry)->target) <= target_len ) {
            AST_RWLIST_INSERT_AFTER(&uri_redirects, cur, redirect, entry);
            AST_RWLIST_UNLOCK(&uri_redirects);
            return;
        }
    }
 
    AST_RWLIST_INSERT_TAIL(&uri_redirects, redirect, entry);
 
    AST_RWLIST_UNLOCK(&uri_redirects);
}
 
/*! \brief Number of HTTP server buckets */
#define HTTP_SERVER_BUCKETS 5
 
struct ao2_container *http_servers = NULL;
 
AO2_STRING_FIELD_HASH_FN(ast_http_server, address);
AO2_STRING_FIELD_CMP_FN(ast_http_server, address);
 
static void http_server_destroy(void *obj)
{
    struct ast_http_server *server = obj;
 
    ast_tcptls_server_stop(&server->args);
 
    ast_verb(1, "Stopped http server '%s' listening at '%s'\n", server->name, server->address);
 
    ast_free(server->name);
    ast_free(server->address);
}
 
static struct ast_http_server *http_server_create(const char *name, const char *address,
    const struct ast_sockaddr *addr)
{
    struct ast_http_server *server;
 
    server = ao2_alloc(sizeof(*server), http_server_destroy);
    if (!server) {
        ast_log(LOG_ERROR, "Unable to allocate HTTP server '%s' at address '%s'\n",
            name, address);
        return NULL;
    }
 
    if (!(server->address = ast_strdup(address)) || !(server->name = ast_strdup(name))) {
        ast_log(LOG_ERROR, "Unable to complete setup for HTTP server '%s' at address '%s'\n",
            name, address);
        ao2_ref(server, -1);
        return NULL;
    }
 
    server->args.accept_fd = -1;
    server->args.master = AST_PTHREADT_NULL;
    server->args.tls_cfg = NULL;
    server->args.poll_timeout = -1;
    server->args.name = server->name;
    server->args.accept_fn = ast_tcptls_server_root;
    server->args.worker_fn = httpd_helper_thread;
 
    ast_sockaddr_copy(&server->args.local_address, addr);
 
    return server;
}
 
static int http_server_start(struct ast_http_server *server)
{
    if (server->args.accept_fd != -1) {
        /* Already running */
        return 0;
    }
 
    ast_tcptls_server_start(&server->args);
    if (server->args.accept_fd == -1) {
        ast_log(LOG_WARNING, "Failed to start HTTP server '%s' at address '%s'\n",
                server->name, server->address);
        return -1;
    }
 
    if (!ao2_link_flags(http_servers, server, OBJ_NOLOCK)) {
        ast_log(LOG_WARNING, "Failed to link HTTP server '%s' at address '%s'\n",
                server->name, server->address);
        return -1;
    }
 
    ast_verb(1, "Bound HTTP server '%s' to address %s\n", server->name, server->address);
 
    return 0;
}
 
/*!
 * \brief Discard/Drop a HTTP server
 *
 * Decrements the reference to the given object, and unlinks it from the servers
 * container if it's the last reference.
 *
 * After a server object has been added to the container this method should always
 * be called to decrement the object's reference instead of the regular ao2 methods.
 *
 * \note NULL tolerant
 *
 * \param server The server object
 */
static void http_server_discard(struct ast_http_server *server)
{
    if (!server) {
        return;
    }
 
    /*
     * If only two references were on the object then the last one is from
     * the servers container, so remove from container now.
     */
    if (ao2_ref(server, -1) == 2) {
        ao2_unlink(http_servers, server);
    }
}
 
/*!
 * \brief Retrieve, or create a HTTP server object by sock address
 *
 * Look for, and return a matching server object by addr. If an object is not found
 * then create a new one.
 *
 * \note This method should be called with the http_servers container already locked.
 *
 * \param name The name of the server
 * \param addr The address to match on, or create a new object with
 *
 * \return a HTTP server object, or NULL on error
 */
static struct ast_http_server *http_server_get_by_addr(
    const char *name, const struct ast_sockaddr *addr)
{
    struct ast_http_server *server;
    const char *address;
 
    address = ast_sockaddr_stringify(addr);
    if (ast_strlen_zero(address)) {
        return NULL;
    }
 
    server = ao2_find(http_servers, address, OBJ_KEY | OBJ_NOLOCK);
 
    return server ?: http_server_create(name, address, addr);
}
 
/*!
 * \brief Retrieve, or create a HTTP server object by host
 *
 * Resolve the given host, and then look for, and return a matching server object.
 * If an object is not found then create a new one.
 *
 * \note This method should be called with the http_servers container already locked.
 *
 * \param name The name of the server
 * \param host The host to resolve, and match on or create a new object with
 * \param port Optional port used if one is not specified with the host (default 8088)
 *
 * \return a HTTP server object, or NULL on error
 */
static struct ast_http_server *http_server_get_by_host(const char *name, const char *host,
    uint32_t port)
{
    struct ast_sockaddr *addrs = NULL;
    int num_addrs;
    int i;
 
    if (!(num_addrs = ast_sockaddr_resolve(&addrs, host, 0, AST_AF_UNSPEC))) {
        ast_log(LOG_WARNING, "Unable to resolve host '%s'\n", host);
        return NULL;
    }
 
    if (port == 0) {
        port = DEFAULT_PORT;
    }
 
    for (i = 0; i < num_addrs; ++i) {
        struct ast_http_server *server;
 
        /* Use the given port if one was not specified already */
        if (!ast_sockaddr_port(&addrs[i])) {
            ast_sockaddr_set_port(&addrs[i], port);
        }
 
        server = http_server_get_by_addr(name, &addrs[i]);
        if (server) {
            ast_free(addrs);
            return server;
        }
    }
 
    ast_free(addrs);
    return NULL;
}
 
/*!
 * \brief Retrieve, or create and start a HTTP server
 *
 * Resolve the given host, and retrieve a listening server object. If the server is
 * not already listening then start it. If a replace_me parameter is given, and it
 * points to a non-NULL value then that server is discarded and replaced.
 *
 * \param name The name of the server
 * \param host The host to resolve, and match on or create a new object with
 * \param port Optional port used if one is not specified with the host (default 8088)
 * \param[out] replace_me Optional server to be replaced
 *
 * \note If replace_me is specified the returned value is always the same as what's
 *       passed back out in the variable.
 *
 * \return a HTTP server object, or NULL on error
 */
static struct ast_http_server *http_server_get(const char *name, const char *host,
    uint32_t port, struct ast_http_server **replace_me)
{
    struct ast_http_server *server;
 
    ao2_lock(http_servers);
 
    server = http_server_get_by_host(name, host, port);
 
    if (replace_me) {
        /* Only replace if different */
        if (*replace_me == server) {
            ao2_cleanup(server);
            ao2_unlock(http_servers);
            return *replace_me;
        }
 
        if (*replace_me) {
            http_server_discard(*replace_me);
        }
 
        *replace_me = server;
    }
 
    if (server && http_server_start(server)) {
        if (replace_me) {
            *replace_me = NULL;
        }
 
        ao2_ref(server, -1);
        server = NULL;
    }
 
    ao2_unlock(http_servers);
    return server;
}
 
#ifdef TEST_FRAMEWORK
 
struct ast_http_server *ast_http_test_server_get(const char *name, const char *host)
{
    struct ast_http_server *server;
 
    /*
     * Currently multiple HTTP servers are only allowed when the TEST_FRAMEWORK
     * is enabled, leaving the follow 'todos' if they become a problem or if this
     * ability moves outside the TEST_FRAMEWORK.
     *
     * TODO: Add locking around global_http_server use. If this module is reloading
     *       it's possible for the global_http_server to exist here, and then become
     *       NULL between the check and return.
     *
     * TODO: Make it so 'localhost' and 'any' addresses equate.
     */
 
    if (ast_strlen_zero(host)) {
        /* Use configured server if one available */
        if (global_http_server) {
            ast_module_ref(ast_module_info->self);
            return ao2_bump(global_http_server);
        }
 
        host = "localhost:8088";
    }
 
    if (!name) {
        name = "http test server";
    }
 
    server = http_server_get(name, host, 0, NULL);
    if (server) {
        ast_module_ref(ast_module_info->self);
    }
 
    return server;
}
 
void ast_http_test_server_discard(struct ast_http_server *server)
{
    if (server) {
        http_server_discard(server);
        ast_module_unref(ast_module_info->self);
    }
}
 
#endif
 
static int __ast_http_load(int reload)
{
    struct ast_config *cfg;
    struct ast_variable *v;
    int enabled = 0;
    int new_static_uri_enabled = 0;
    int new_status_uri_enabled = 0;
    char newprefix[MAX_PREFIX] = "";
    char server_name[MAX_SERVER_NAME_LENGTH];
    struct http_uri_redirect *redirect;
    struct http_restriction *restriction;
    struct http_restriction_list new_restrictions = AST_LIST_HEAD_NOLOCK_INIT_VALUE;
    struct http_restriction_list old_restrictions = AST_LIST_HEAD_NOLOCK_INIT_VALUE;
    struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 };
    uint32_t bindport = DEFAULT_PORT;
    int http_tls_was_enabled = 0;
    const char *bindaddr = NULL;
    const char *cat = NULL;
 
    cfg = ast_config_load2("http.conf", "http", config_flags);
    if (!cfg || cfg == CONFIG_STATUS_FILEINVALID) {
        return 0;
    }
 
    /* Even if the http.conf hasn't been updated, the TLS certs/keys may have been */
    if (cfg == CONFIG_STATUS_FILEUNCHANGED) {
        if (http_tls_cfg.enabled && ast_ssl_setup(https_desc.tls_cfg)) {
            ast_tcptls_server_start(&https_desc);
        }
        return 0;
    }
 
    http_tls_was_enabled = (reload && http_tls_cfg.enabled);
 
    http_tls_cfg.enabled = 0;
 
    ast_free(http_tls_cfg.certfile);
    http_tls_cfg.certfile = ast_strdup(AST_CERTFILE);
 
    ast_free(http_tls_cfg.capath);
    http_tls_cfg.capath = ast_strdup("");
 
    ast_free(http_tls_cfg.pvtfile);
    http_tls_cfg.pvtfile = ast_strdup("");
 
    /* Apply modern intermediate settings according to the Mozilla OpSec team as of July 30th, 2015 but disable TLSv1 */
    ast_set_flag(&http_tls_cfg.flags, AST_SSL_DISABLE_TLSV1 | AST_SSL_SERVER_CIPHER_ORDER);
 
    ast_free(http_tls_cfg.cipher);
    http_tls_cfg.cipher = ast_strdup("ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:AES128-SHA256:AES256-SHA256:AES128-SHA:AES256-SHA:AES:CAMELLIA:DES-CBC3-SHA:!aNULL:!eNULL:!EXPORT:!DES:!RC4:!MD5:!PSK:!aECDH:!EDH-DSS-DES-CBC3-SHA:!EDH-RSA-DES-CBC3-SHA:!KRB5-DES-CBC3-SHA");
 
    AST_RWLIST_WRLOCK(&uri_redirects);
    while ((redirect = AST_RWLIST_REMOVE_HEAD(&uri_redirects, entry))) {
        ast_free(redirect);
    }
    AST_RWLIST_UNLOCK(&uri_redirects);
 
    ast_sockaddr_setnull(&https_desc.local_address);
 
    session_limit = DEFAULT_SESSION_LIMIT;
    session_inactivity = DEFAULT_SESSION_INACTIVITY;
    session_keep_alive = DEFAULT_SESSION_KEEP_ALIVE;
 
    snprintf(server_name, sizeof(server_name), "Asterisk/%s", ast_get_version());
 
    v = ast_variable_browse(cfg, "general");
    for (; v; v = v->next) {
        /* read tls config options while preventing unsupported options from being set */
        if (strcasecmp(v->name, "tlscafile")
            && strcasecmp(v->name, "tlscapath")
            && strcasecmp(v->name, "tlscadir")
            && strcasecmp(v->name, "tlsverifyclient")
            && strcasecmp(v->name, "tlsdontverifyserver")
            && strcasecmp(v->name, "tlsclientmethod")
            && strcasecmp(v->name, "sslclientmethod")
            && !ast_tls_read_conf(&http_tls_cfg, &https_desc, v->name, v->value)) {
            continue;
        }
 
        if (!strcasecmp(v->name, "servername")) {
            if (!ast_strlen_zero(v->value)) {
                ast_copy_string(server_name, v->value, sizeof(server_name));
            } else {
                server_name[0] = '\0';
            }
        } else if (!strcasecmp(v->name, "enabled")) {
            enabled = ast_true(v->value);
        } else if (!strcasecmp(v->name, "enablestatic") || !strcasecmp(v->name, "enable_static")) {
            new_static_uri_enabled = ast_true(v->value);
        } else if (!strcasecmp(v->name, "enable_status")) {
            new_status_uri_enabled = ast_true(v->value);
        } else if (!strcasecmp(v->name, "bindport")) {
            if (ast_parse_arg(v->value, PARSE_UINT32 | PARSE_IN_RANGE | PARSE_DEFAULT,
                &bindport, DEFAULT_PORT, 0, 65535)) {
                ast_log(LOG_WARNING, "Invalid port %s specified. Using default port %" PRId32 "\n",
                    v->value, DEFAULT_PORT);
            }
        } else if (!strcasecmp(v->name, "bindaddr")) {
            bindaddr = ast_strdupa(v->value);
        } else if (!strcasecmp(v->name, "prefix")) {
            if (!ast_strlen_zero(v->value)) {
                newprefix[0] = '/';
                ast_copy_string(newprefix + 1, v->value, sizeof(newprefix) - 1);
            } else {
                newprefix[0] = '\0';
            }
        } else if (!strcasecmp(v->name, "redirect")) {
            add_redirect(v->value);
        } else if (!strcasecmp(v->name, "sessionlimit")) {
            if (ast_parse_arg(v->value, PARSE_INT32 | PARSE_DEFAULT | PARSE_IN_RANGE,
                &session_limit, DEFAULT_SESSION_LIMIT, 1, INT_MAX)) {
                ast_log(LOG_WARNING, "Invalid %s '%s' at line %d of http.conf\n",
                    v->name, v->value, v->lineno);
            }
        } else if (!strcasecmp(v->name, "session_inactivity")) {
            if (ast_parse_arg(v->value, PARSE_INT32 | PARSE_DEFAULT | PARSE_IN_RANGE,
                &session_inactivity, DEFAULT_SESSION_INACTIVITY, 1, INT_MAX)) {
                ast_log(LOG_WARNING, "Invalid %s '%s' at line %d of http.conf\n",
                    v->name, v->value, v->lineno);
            }
        } else if (!strcasecmp(v->name, "session_keep_alive")) {
            if (sscanf(v->value, "%30d", &session_keep_alive) != 1
                || session_keep_alive < 0) {
                session_keep_alive = DEFAULT_SESSION_KEEP_ALIVE;
                ast_log(LOG_WARNING, "Invalid %s '%s' at line %d of http.conf\n",
                    v->name, v->value, v->lineno);
            }
        } else {
            ast_log(LOG_WARNING, "Ignoring unknown option '%s' in http.conf\n", v->name);
        }
    }
 
    while ((cat = ast_category_browse(cfg, cat))) {
        const char *type;
        struct http_restriction *new_restriction;
        struct ast_acl_list *acl = NULL;
        int acl_error = 0;
        int acl_subscription_flag = 0;
 
        if (strcasecmp(cat, "general") == 0) {
            continue;
        }
 
        type = ast_variable_retrieve(cfg, cat, "type");
        if (!type || strcasecmp(type, "restriction") != 0) {
            continue;
        }
 
        new_restriction = ast_calloc(1, sizeof(*new_restriction) + strlen(cat) + 1);
        if (!new_restriction) {
            continue;
        }
 
        /* Safe */
        strcpy(new_restriction->path, cat);
 
        /* Parse ACL options for this restriction */
        for (v = ast_variable_browse(cfg, cat); v; v = v->next) {
            if (!strcasecmp(v->name, "permit") ||
                !strcasecmp(v->name, "deny") ||
                !strcasecmp(v->name, "acl")) {
                ast_append_acl(v->name, v->value, &acl, &acl_error, &acl_subscription_flag);
                if (acl_error) {
                    ast_log(LOG_ERROR, "Bad ACL '%s' at line '%d' of http.conf for restriction '%s'\n",
                        v->value, v->lineno, cat);
                }
            }
        }
 
        new_restriction->acl = acl;
 
        AST_LIST_INSERT_TAIL(&new_restrictions, new_restriction, entry);
        ast_debug(2, "HTTP: Added restriction for path '%s'\n", cat);
    }
 
    AST_RWLIST_WRLOCK(&restrictions);
    AST_RWLIST_APPEND_LIST(&old_restrictions, &restrictions, entry);
    AST_RWLIST_APPEND_LIST(&restrictions, &new_restrictions, entry);
    AST_RWLIST_UNLOCK(&restrictions);
 
    while ((restriction = AST_LIST_REMOVE_HEAD(&old_restrictions, entry))) {
        if (restriction->acl) {
            ast_free_acl_list(restriction->acl);
        }
        ast_free(restriction);
    }
 
    ast_config_destroy(cfg);
 
    if (strcmp(prefix, newprefix)) {
        ast_copy_string(prefix, newprefix, sizeof(prefix));
    }
 
    ast_copy_string(http_server_name, server_name, sizeof(http_server_name));
 
    if (enabled) {
        http_server_get("http server", bindaddr, bindport, &global_http_server);
    } else if (global_http_server) {
        http_server_discard(global_http_server);
        global_http_server = NULL;
    }
 
    /* When no specific TLS bindaddr is specified, we just use
     * the non-TLS bindaddress here.
     */
    if (global_http_server && ast_sockaddr_isnull(&https_desc.local_address) &&
        global_http_server->args.accept_fd != -1) {
 
        ast_sockaddr_copy(&https_desc.local_address, &global_http_server->args.local_address);
        /* Of course, we can't use the same port though.
         * Since no bind address was specified, we just use the
         * default TLS port
         */
        ast_sockaddr_set_port(&https_desc.local_address, DEFAULT_TLS_PORT);
    }
 
    if (http_tls_was_enabled && !http_tls_cfg.enabled) {
        ast_tcptls_server_stop(&https_desc);
    } else if (http_tls_cfg.enabled && !ast_sockaddr_isnull(&https_desc.local_address)) {
        /* We can get here either because a TLS-specific address was specified
         * or because we copied the non-TLS address here. In the case where
         * we read an explicit address from the config, there may have been
         * no port specified, so we'll just use the default TLS port.
         */
        if (!ast_sockaddr_port(&https_desc.local_address)) {
            ast_sockaddr_set_port(&https_desc.local_address, DEFAULT_TLS_PORT);
        }
        if (ast_ssl_setup(https_desc.tls_cfg)) {
            ast_tcptls_server_start(&https_desc);
        }
    }
 
    if (static_uri_enabled && !new_static_uri_enabled) {
        ast_http_uri_unlink(&static_uri);
    } else if (!static_uri_enabled && new_static_uri_enabled) {
        ast_http_uri_link(&static_uri);
    }
 
    static_uri_enabled = new_static_uri_enabled;
 
    if (status_uri_enabled && !new_status_uri_enabled) {
        ast_http_uri_unlink(&status_uri);
    } else if (!status_uri_enabled && new_status_uri_enabled) {
        ast_http_uri_link(&status_uri);
    }
 
    status_uri_enabled = new_status_uri_enabled;
 
    return 0;
}
 
static char *handle_show_http(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
{
    struct ast_http_uri *urih;
    struct http_uri_redirect *redirect;
 
    switch (cmd) {
    case CLI_INIT:
        e->command = "http show status";
        e->usage =
            "Usage: http show status\n"
            "       Lists status of internal HTTP engine\n";
        return NULL;
    case CLI_GENERATE:
        return NULL;
    }
 
    if (a->argc != 3) {
        return CLI_SHOWUSAGE;
    }
    ast_cli(a->fd, "HTTP Server Status:\n");
    ast_cli(a->fd, "Prefix: %s\n", prefix);
    ast_cli(a->fd, "Server: %s\n", http_server_name);
    if (!global_http_server) {
        ast_cli(a->fd, "Server Disabled\n\n");
    } else {
        ast_cli(a->fd, "Server Enabled and Bound to %s\n\n",
            ast_sockaddr_stringify(&global_http_server->args.old_address));
        if (http_tls_cfg.enabled) {
            ast_cli(a->fd, "HTTPS Server Enabled and Bound to %s\n\n",
                ast_sockaddr_stringify(&https_desc.old_address));
        }
    }
 
    ast_cli(a->fd, "Enabled URI's:\n");
    AST_RWLIST_RDLOCK(&uris);
    if (AST_RWLIST_EMPTY(&uris)) {
        ast_cli(a->fd, "None.\n");
    } else {
        AST_RWLIST_TRAVERSE(&uris, urih, entry)
            ast_cli(a->fd, "%s/%s%s => %s\n", prefix, urih->uri, (urih->has_subtree ? "/..." : "" ), urih->description);
    }
    AST_RWLIST_UNLOCK(&uris);
 
    ast_cli(a->fd, "\nEnabled Redirects:\n");
    AST_RWLIST_RDLOCK(&uri_redirects);
    if (AST_RWLIST_EMPTY(&uri_redirects)) {
        ast_cli(a->fd, "  None.\n");
    } else {
        AST_RWLIST_TRAVERSE(&uri_redirects, redirect, entry)
            ast_cli(a->fd, "  %s => %s\n", redirect->target, redirect->dest);
    }
    AST_RWLIST_UNLOCK(&uri_redirects);
 
    ast_cli(a->fd, "\nPath Restrictions:\n");
    AST_RWLIST_RDLOCK(&restrictions);
    if (AST_RWLIST_EMPTY(&restrictions)) {
        ast_cli(a->fd, "  None.\n");
    } else {
        struct http_restriction *restriction;
        AST_RWLIST_TRAVERSE(&restrictions, restriction, entry) {
            ast_cli(a->fd, "  Path: %s\n", restriction->path);
            if (restriction->acl && !ast_acl_list_is_empty(restriction->acl)) {
                ast_acl_output(a->fd, restriction->acl, "    ");
            } else {
                ast_cli(a->fd, "    No ACL configured\n");
            }
        }
    }
    AST_RWLIST_UNLOCK(&restrictions);
 
    return CLI_SUCCESS;
}
 
static int reload_module(void)
{
    return __ast_http_load(1);
}
 
static struct ast_cli_entry cli_http[] = {
    AST_CLI_DEFINE(handle_show_http, "Display HTTP server status"),
};
 
static int unload_module(void)
{
    struct http_uri_redirect *redirect;
    struct http_restriction *restriction;
    ast_cli_unregister_multiple(cli_http, ARRAY_LEN(cli_http));
 
    ao2_cleanup(global_http_server);
    ao2_cleanup(http_servers);
 
    if (http_tls_cfg.enabled) {
        ast_tcptls_server_stop(&https_desc);
    }
    ast_free(http_tls_cfg.certfile);
    ast_free(http_tls_cfg.capath);
    ast_free(http_tls_cfg.pvtfile);
    ast_free(http_tls_cfg.cipher);
 
    if (status_uri_enabled) {
        ast_http_uri_unlink(&status_uri);
    }
 
    if (static_uri_enabled) {
        ast_http_uri_unlink(&static_uri);
    }
 
    AST_RWLIST_WRLOCK(&uri_redirects);
    while ((redirect = AST_RWLIST_REMOVE_HEAD(&uri_redirects, entry))) {
        ast_free(redirect);
    }
    AST_RWLIST_UNLOCK(&uri_redirects);
 
    AST_RWLIST_WRLOCK(&restrictions);
    while ((restriction = AST_RWLIST_REMOVE_HEAD(&restrictions, entry))) {
        if (restriction->acl) {
            ast_free_acl_list(restriction->acl);
        }
        ast_free(restriction);
    }
    AST_RWLIST_UNLOCK(&restrictions);
 
    return 0;
}
 
static int load_module(void)
{
    ast_cli_register_multiple(cli_http, ARRAY_LEN(cli_http));
 
    http_servers = ao2_container_alloc_hash(AO2_ALLOC_OPT_LOCK_MUTEX, 0,
        HTTP_SERVER_BUCKETS, ast_http_server_hash_fn, NULL, ast_http_server_cmp_fn);
    if (!http_servers) {
        return AST_MODULE_LOAD_FAILURE;
    }
 
    if (__ast_http_load(0)) {
        ao2_cleanup(http_servers);
        http_servers = NULL;
        return AST_MODULE_LOAD_FAILURE;
    }
 
    return AST_MODULE_LOAD_SUCCESS;
}
 
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_GLOBAL_SYMBOLS | AST_MODFLAG_LOAD_ORDER, "Built-in HTTP Server",
    .support_level = AST_MODULE_SUPPORT_CORE,
    .load = load_module,
    .unload = unload_module,
    .reload = reload_module,
    .load_pri = AST_MODPRI_CORE,
    .requires = "extconfig",
);