asterisk/main/tcptls.c

993 lines
31 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 2007 - 2008, Digium, Inc.
*
* Luigi Rizzo (TCP and TLS server code)
* Brett Bryant <brettbryant@gmail.com> (updated for client support)
*
* 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 Code to support TCP and TLS server/client
*
* \author Luigi Rizzo
* \author Brett Bryant <brettbryant@gmail.com>
*/
#include "asterisk.h"
#include "asterisk/tcptls.h" /* for ast_tls_config, ast_tcptls_se... */
#include "asterisk/iostream.h" /* for DO_SSL, ast_iostream_close, a... */
#ifdef HAVE_FCNTL_H
#include <fcntl.h> /* for O_NONBLOCK */
#endif /* HAVE_FCNTL_H */
#include <netinet/in.h> /* for IPPROTO_TCP */
#ifdef DO_SSL
#include <openssl/asn1.h> /* for ASN1_STRING_to_UTF8 */
#include <openssl/crypto.h> /* for OPENSSL_free */
#include <openssl/err.h> /* for ERR_print_errors_fp */
#include <openssl/opensslconf.h> /* for OPENSSL_NO_SSL3_METHOD, OPENS... */
#include <openssl/opensslv.h> /* for OPENSSL_VERSION_NUMBER */
#include <openssl/safestack.h> /* for STACK_OF */
#include <openssl/ssl.h> /* for SSL_CTX_free, SSL_get_error, ... */
#include <openssl/x509.h> /* for X509_free, X509_NAME_ENTRY_ge... */
#include <openssl/x509v3.h> /* for GENERAL_NAME, sk_GENERAL_NAME... */
#ifndef OPENSSL_NO_DH
#include <openssl/bio.h> /* for BIO_free, BIO_new_file */
#include <openssl/dh.h> /* for DH_free */
#include <openssl/pem.h> /* for PEM_read_bio_DHparams */
#endif /* OPENSSL_NO_DH */
#ifndef OPENSSL_NO_EC
#include <openssl/ec.h> /* for EC_KEY_free, EC_KEY_new_by_cu... */
#endif /* OPENSSL_NO_EC */
#endif /* DO_SSL */
#include <pthread.h> /* for pthread_cancel, pthread_join */
#include <signal.h> /* for pthread_kill, SIGURG */
#include <sys/socket.h> /* for setsockopt, shutdown, socket */
#include <sys/stat.h> /* for stat */
#include "asterisk/app.h" /* for ast_read_textfile */
#include "asterisk/astobj2.h" /* for ao2_ref, ao2_t_ref, ao2_alloc */
#include "asterisk/compat.h" /* for strcasecmp */
#include "asterisk/config.h" /* for ast_parse_arg, ast_parse_flag... */
#include "asterisk/io.h" /* for ast_sd_get_fd */
#include "asterisk/lock.h" /* for AST_PTHREADT_NULL */
#include "asterisk/logger.h" /* for ast_log, LOG_ERROR, ast_debug */
#include "asterisk/netsock2.h" /* for ast_sockaddr_copy, ast_sockad... */
#include "asterisk/pbx.h" /* for ast_thread_inhibit_escalations */
#include "asterisk/utils.h" /* for ast_true, ast_free, ast_wait_... */
static void session_instance_destructor(void *obj)
{
struct ast_tcptls_session_instance *i = obj;
if (i->stream) {
ast_iostream_close(i->stream);
i->stream = NULL;
}
ast_free(i->overflow_buf);
ao2_cleanup(i->private_data);
}
#ifdef DO_SSL
static int check_tcptls_cert_name(ASN1_STRING *cert_str, const char *hostname, const char *desc)
{
unsigned char *str;
int ret;
ret = ASN1_STRING_to_UTF8(&str, cert_str);
if (ret < 0 || !str) {
return -1;
}
if (strlen((char *) str) != ret) {
ast_log(LOG_WARNING, "Invalid certificate %s length (contains NULL bytes?)\n", desc);
ret = -1;
} else if (!strcasecmp(hostname, (char *) str)) {
ret = 0;
} else {
ret = -1;
}
ast_debug(3, "SSL %s compare s1='%s' s2='%s'\n", desc, hostname, str);
OPENSSL_free(str);
return ret;
}
static void write_openssl_error_to_log(void)
{
FILE *fp;
char *buffer;
size_t length;
fp = open_memstream(&buffer, &length);
if (!fp) {
return;
}
ERR_print_errors_fp(fp);
fclose(fp);
if (length) {
ast_log(LOG_ERROR, "%.*s\n", (int) length, buffer);
}
ast_free(buffer);
}
#endif
/*! \brief
* creates a FILE * from the fd passed by the accept thread.
* This operation is potentially expensive (certificate verification),
* so we do it in the child thread context.
*
* \note must decrement ref count before returning NULL on error
*/
static void *handle_tcptls_connection(void *data)
{
struct ast_tcptls_session_instance *tcptls_session = data;
#ifdef DO_SSL
SSL *ssl;
#endif
/* TCP/TLS connections are associated with external protocols, and
* should not be allowed to execute 'dangerous' functions. This may
* need to be pushed down into the individual protocol handlers, but
* this seems like a good general policy.
*/
if (ast_thread_inhibit_escalations()) {
ast_log(LOG_ERROR, "Failed to inhibit privilege escalations; killing connection from peer '%s'\n",
ast_sockaddr_stringify(&tcptls_session->remote_address));
ast_tcptls_close_session_file(tcptls_session);
ao2_ref(tcptls_session, -1);
return NULL;
}
/*
* TCP/TLS connections are associated with external protocols which can
* be considered to be user interfaces (even for SIP messages), and
* will not handle channel media. This may need to be pushed down into
* the individual protocol handlers, but this seems like a good start.
*/
if (ast_thread_user_interface_set(1)) {
ast_log(LOG_ERROR, "Failed to set user interface status; killing connection from peer '%s'\n",
ast_sockaddr_stringify(&tcptls_session->remote_address));
ast_tcptls_close_session_file(tcptls_session);
ao2_ref(tcptls_session, -1);
return NULL;
}
if (tcptls_session->parent->tls_cfg) {
#ifdef DO_SSL
if (ast_iostream_start_tls(&tcptls_session->stream, tcptls_session->parent->tls_cfg->ssl_ctx, tcptls_session->client) < 0) {
SSL *ssl = ast_iostream_get_ssl(tcptls_session->stream);
if (ssl) {
ast_log(LOG_ERROR, "Unable to set up ssl connection with peer '%s'\n",
ast_sockaddr_stringify(&tcptls_session->remote_address));
}
ast_tcptls_close_session_file(tcptls_session);
ao2_ref(tcptls_session, -1);
return NULL;
}
ssl = ast_iostream_get_ssl(tcptls_session->stream);
if ((tcptls_session->client && !ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_DONT_VERIFY_SERVER))
|| (!tcptls_session->client && ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_VERIFY_CLIENT))) {
X509 *peer;
long res;
peer = SSL_get_peer_certificate(ssl);
if (!peer) {
ast_log(LOG_ERROR, "No SSL certificate to verify from peer '%s'\n",
ast_sockaddr_stringify(&tcptls_session->remote_address));
ast_tcptls_close_session_file(tcptls_session);
ao2_ref(tcptls_session, -1);
return NULL;
}
res = SSL_get_verify_result(ssl);
if (res != X509_V_OK) {
ast_log(LOG_ERROR, "Certificate from peer '%s' did not verify: %s\n",
ast_sockaddr_stringify(&tcptls_session->remote_address),
X509_verify_cert_error_string(res));
X509_free(peer);
ast_tcptls_close_session_file(tcptls_session);
ao2_ref(tcptls_session, -1);
return NULL;
}
if (!ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_IGNORE_COMMON_NAME)) {
ASN1_STRING *str;
X509_NAME *name = X509_get_subject_name(peer);
STACK_OF(GENERAL_NAME) *alt_names;
int pos = -1;
int found = 0;
for (;;) {
/* Walk the certificate to check all available "Common Name" */
/* XXX Probably should do a gethostbyname on the hostname and compare that as well */
pos = X509_NAME_get_index_by_NID(name, NID_commonName, pos);
if (pos < 0) {
break;
}
str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(name, pos));
if (!check_tcptls_cert_name(str, tcptls_session->parent->hostname, "common name")) {
found = 1;
break;
}
}
if (!found) {
alt_names = X509_get_ext_d2i(peer, NID_subject_alt_name, NULL, NULL);
if (alt_names != NULL) {
int alt_names_count = sk_GENERAL_NAME_num(alt_names);
for (pos = 0; pos < alt_names_count; pos++) {
const GENERAL_NAME *alt_name = sk_GENERAL_NAME_value(alt_names, pos);
if (alt_name->type != GEN_DNS) {
continue;
}
if (!check_tcptls_cert_name(alt_name->d.dNSName, tcptls_session->parent->hostname, "alt name")) {
found = 1;
break;
}
}
sk_GENERAL_NAME_pop_free(alt_names, GENERAL_NAME_free);
}
}
if (!found) {
ast_log(LOG_ERROR, "Certificate common name from peer '%s' did not match (%s)\n",
ast_sockaddr_stringify(&tcptls_session->remote_address), tcptls_session->parent->hostname);
X509_free(peer);
ast_tcptls_close_session_file(tcptls_session);
ao2_ref(tcptls_session, -1);
return NULL;
}
}
X509_free(peer);
}
#else
ast_log(LOG_ERROR, "TLS client failed: Asterisk is compiled without OpenSSL support. Install OpenSSL development headers and rebuild Asterisk after running ./configure\n");
ast_tcptls_close_session_file(tcptls_session);
ao2_ref(tcptls_session, -1);
return NULL;
#endif /* DO_SSL */
}
if (tcptls_session->parent->worker_fn) {
return tcptls_session->parent->worker_fn(tcptls_session);
} else {
return tcptls_session;
}
}
void *ast_tcptls_server_root(void *data)
{
struct ast_tcptls_session_args *desc = data;
int fd;
struct ast_sockaddr addr;
struct ast_tcptls_session_instance *tcptls_session;
pthread_t launched;
for (;;) {
int i;
if (desc->periodic_fn) {
desc->periodic_fn(desc);
}
i = ast_wait_for_input(desc->accept_fd, desc->poll_timeout);
if (i <= 0) {
/* Prevent tight loop from hogging CPU */
usleep(1);
continue;
}
fd = ast_accept(desc->accept_fd, &addr);
if (fd < 0) {
if (errno != EAGAIN
&& errno != EWOULDBLOCK
&& errno != EINTR
&& errno != ECONNABORTED) {
ast_log(LOG_ERROR, "TCP/TLS accept failed: %s\n", strerror(errno));
if (errno != EMFILE) {
break;
}
}
/* Prevent tight loop from hogging CPU */
usleep(1);
continue;
}
tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor);
if (!tcptls_session) {
close(fd);
continue;
}
tcptls_session->overflow_buf = ast_str_create(128);
if (!tcptls_session->overflow_buf) {
ao2_ref(tcptls_session, -1);
close(fd);
continue;
}
ast_fd_clear_flags(fd, O_NONBLOCK);
tcptls_session->stream = ast_iostream_from_fd(&fd);
if (!tcptls_session->stream) {
ao2_ref(tcptls_session, -1);
close(fd);
continue;
}
tcptls_session->parent = desc;
ast_sockaddr_copy(&tcptls_session->remote_address, &addr);
tcptls_session->client = 0;
/* This thread is now the only place that controls the single ref to tcptls_session */
if (ast_pthread_create_detached_background(&launched, NULL, handle_tcptls_connection, tcptls_session)) {
ast_log(LOG_ERROR, "TCP/TLS unable to launch helper thread for peer '%s': %s\n",
ast_sockaddr_stringify(&tcptls_session->remote_address),
strerror(errno));
ao2_ref(tcptls_session, -1);
}
}
ast_log(LOG_ERROR, "TCP/TLS listener thread ended abnormally\n");
/* Close the listener socket so Asterisk doesn't appear dead. */
fd = desc->accept_fd;
desc->accept_fd = -1;
if (0 <= fd) {
close(fd);
}
return NULL;
}
#ifdef DO_SSL
static void __ssl_setup_certs(struct ast_tls_config *cfg, const size_t cert_file_len, const char *key_type_extension, const char *key_type)
{
char *cert_file = ast_strdupa(cfg->certfile);
memcpy(cert_file + cert_file_len - 8, key_type_extension, 5);
if (access(cert_file, F_OK) == 0) {
if (SSL_CTX_use_certificate_chain_file(cfg->ssl_ctx, cert_file) == 0) {
ast_log(LOG_WARNING, "TLS/SSL error loading public %s key (certificate) from <%s>.\n", key_type, cert_file);
write_openssl_error_to_log();
} else if (SSL_CTX_use_PrivateKey_file(cfg->ssl_ctx, cert_file, SSL_FILETYPE_PEM) == 0) {
ast_log(LOG_WARNING, "TLS/SSL error loading private %s key from <%s>.\n", key_type, cert_file);
write_openssl_error_to_log();
} else if (SSL_CTX_check_private_key(cfg->ssl_ctx) == 0) {
ast_log(LOG_WARNING, "TLS/SSL error matching private %s key and certificate in <%s>.\n", key_type, cert_file);
write_openssl_error_to_log();
}
}
}
#endif
static int __ssl_setup(struct ast_tls_config *cfg, int client)
{
#ifndef DO_SSL
if (cfg->enabled) {
ast_log(LOG_ERROR, "TLS server failed: Asterisk is compiled without OpenSSL support. Install OpenSSL development headers and rebuild Asterisk after running ./configure\n");
cfg->enabled = 0;
}
return 0;
#else
int disable_ssl = 0;
long ssl_opts = 0;
if (!cfg->enabled) {
return 0;
}
/* Get rid of an old SSL_CTX since we're about to
* allocate a new one
*/
if (cfg->ssl_ctx) {
SSL_CTX_free(cfg->ssl_ctx);
cfg->ssl_ctx = NULL;
}
if (client) {
#if !defined(OPENSSL_NO_SSL2) && (OPENSSL_VERSION_NUMBER < 0x10100000L)
if (ast_test_flag(&cfg->flags, AST_SSL_SSLV2_CLIENT)) {
ast_log(LOG_WARNING, "Usage of SSLv2 is discouraged due to known vulnerabilities. Please use 'tlsv1' or leave the TLS method unspecified!\n");
cfg->ssl_ctx = SSL_CTX_new(SSLv2_client_method());
} else
#endif
#if !defined(OPENSSL_NO_SSL3_METHOD) && !(defined(OPENSSL_API_COMPAT) && (OPENSSL_API_COMPAT >= 0x10100000L))
if (ast_test_flag(&cfg->flags, AST_SSL_SSLV3_CLIENT)) {
ast_log(LOG_WARNING, "Usage of SSLv3 is discouraged due to known vulnerabilities. Please use 'tlsv1' or leave the TLS method unspecified!\n");
cfg->ssl_ctx = SSL_CTX_new(SSLv3_client_method());
} else
#endif
#if OPENSSL_VERSION_NUMBER >= 0x10100000L
cfg->ssl_ctx = SSL_CTX_new(TLS_client_method());
#else
if (ast_test_flag(&cfg->flags, AST_SSL_TLSV1_CLIENT)) {
cfg->ssl_ctx = SSL_CTX_new(TLSv1_client_method());
} else {
disable_ssl = 1;
cfg->ssl_ctx = SSL_CTX_new(SSLv23_client_method());
}
#endif
} else {
disable_ssl = 1;
cfg->ssl_ctx = SSL_CTX_new(SSLv23_server_method());
}
if (!cfg->ssl_ctx) {
ast_debug(1, "Sorry, SSL_CTX_new call returned null...\n");
cfg->enabled = 0;
return 0;
}
/* Due to the POODLE vulnerability, completely disable
* SSLv2 and SSLv3 if we are not explicitly told to use
* them. SSLv23_*_method supports TLSv1+.
*/
if (disable_ssl) {
ssl_opts |= SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3;
}
if (ast_test_flag(&cfg->flags, AST_SSL_SERVER_CIPHER_ORDER)) {
ssl_opts |= SSL_OP_CIPHER_SERVER_PREFERENCE;
}
if (ast_test_flag(&cfg->flags, AST_SSL_DISABLE_TLSV1)) {
ssl_opts |= SSL_OP_NO_TLSv1;
}
#if defined(SSL_OP_NO_TLSv1_1) && defined(SSL_OP_NO_TLSv1_2)
if (ast_test_flag(&cfg->flags, AST_SSL_DISABLE_TLSV11)) {
ssl_opts |= SSL_OP_NO_TLSv1_1;
}
if (ast_test_flag(&cfg->flags, AST_SSL_DISABLE_TLSV12)) {
ssl_opts |= SSL_OP_NO_TLSv1_2;
}
#else
ast_log(LOG_WARNING, "Your version of OpenSSL leaves you potentially vulnerable "
"to the SSL BEAST attack. Please upgrade to OpenSSL 1.0.1 or later\n");
#endif
SSL_CTX_set_options(cfg->ssl_ctx, ssl_opts);
SSL_CTX_set_verify(cfg->ssl_ctx,
ast_test_flag(&cfg->flags, AST_SSL_VERIFY_CLIENT) ? SSL_VERIFY_PEER | SSL_VERIFY_FAIL_IF_NO_PEER_CERT : SSL_VERIFY_NONE,
NULL);
if (!ast_strlen_zero(cfg->certfile)) {
char *tmpprivate = ast_strlen_zero(cfg->pvtfile) ? cfg->certfile : cfg->pvtfile;
if (SSL_CTX_use_certificate_chain_file(cfg->ssl_ctx, cfg->certfile) == 0) {
if (!client) {
/* Clients don't need a certificate, but if its setup we can use it */
ast_log(LOG_ERROR, "TLS/SSL error loading cert file. <%s>\n", cfg->certfile);
write_openssl_error_to_log();
cfg->enabled = 0;
SSL_CTX_free(cfg->ssl_ctx);
cfg->ssl_ctx = NULL;
return 0;
}
}
if ((SSL_CTX_use_PrivateKey_file(cfg->ssl_ctx, tmpprivate, SSL_FILETYPE_PEM) == 0) || (SSL_CTX_check_private_key(cfg->ssl_ctx) == 0 )) {
if (!client) {
/* Clients don't need a private key, but if its setup we can use it */
ast_log(LOG_ERROR, "TLS/SSL error loading private key file. <%s>\n", tmpprivate);
write_openssl_error_to_log();
cfg->enabled = 0;
SSL_CTX_free(cfg->ssl_ctx);
cfg->ssl_ctx = NULL;
return 0;
}
}
if (!client) {
size_t certfile_len = strlen(cfg->certfile);
/* expects a file name which contains _rsa. like asterisk_rsa.pem
* ignores any 3-character file-extension like .pem, .cer, .crt
*/
if (certfile_len >= 8 && !strncmp(cfg->certfile + certfile_len - 8, "_rsa.", 5)) {
__ssl_setup_certs(cfg, certfile_len, "_ecc.", "ECC");
__ssl_setup_certs(cfg, certfile_len, "_dsa.", "DSA");
}
}
}
if (!ast_strlen_zero(cfg->cipher)) {
if (SSL_CTX_set_cipher_list(cfg->ssl_ctx, cfg->cipher) == 0 ) {
if (!client) {
ast_log(LOG_ERROR, "TLS/SSL cipher error <%s>\n", cfg->cipher);
write_openssl_error_to_log();
cfg->enabled = 0;
SSL_CTX_free(cfg->ssl_ctx);
cfg->ssl_ctx = NULL;
return 0;
}
}
}
if (!ast_strlen_zero(cfg->cafile) || !ast_strlen_zero(cfg->capath)) {
if (SSL_CTX_load_verify_locations(cfg->ssl_ctx, S_OR(cfg->cafile, NULL), S_OR(cfg->capath,NULL)) == 0) {
ast_log(LOG_ERROR, "TLS/SSL CA file(%s)/path(%s) error\n", cfg->cafile, cfg->capath);
write_openssl_error_to_log();
}
}
#ifndef OPENSSL_NO_DH
if (!ast_strlen_zero(cfg->pvtfile)) {
BIO *bio = BIO_new_file(cfg->pvtfile, "r");
if (bio != NULL) {
DH *dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
if (dh != NULL) {
if (SSL_CTX_set_tmp_dh(cfg->ssl_ctx, dh)) {
long options = SSL_OP_CIPHER_SERVER_PREFERENCE | SSL_OP_SINGLE_DH_USE | SSL_OP_SINGLE_ECDH_USE;
options = SSL_CTX_set_options(cfg->ssl_ctx, options);
ast_verb(2, "TLS/SSL DH initialized, PFS cipher-suites enabled\n");
}
DH_free(dh);
}
BIO_free(bio);
}
}
#endif
#ifndef SSL_CTRL_SET_ECDH_AUTO
#define SSL_CTRL_SET_ECDH_AUTO 94
#endif
/* SSL_CTX_set_ecdh_auto(cfg->ssl_ctx, on); requires OpenSSL 1.0.2 which wraps: */
if (SSL_CTX_ctrl(cfg->ssl_ctx, SSL_CTRL_SET_ECDH_AUTO, 1, NULL)) {
ast_verb(2, "TLS/SSL ECDH initialized (automatic), faster PFS ciphers enabled\n");
#if !defined(OPENSSL_NO_ECDH) && (OPENSSL_VERSION_NUMBER >= 0x10000000L) && (OPENSSL_VERSION_NUMBER < 0x10100000L)
} else {
/* enables AES-128 ciphers, to get AES-256 use NID_secp384r1 */
EC_KEY *ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
if (ecdh != NULL) {
if (SSL_CTX_set_tmp_ecdh(cfg->ssl_ctx, ecdh)) {
ast_verb(2, "TLS/SSL ECDH initialized (secp256r1), faster PFS cipher-suites enabled\n");
}
EC_KEY_free(ecdh);
}
#endif
}
ast_verb(2, "TLS/SSL certificate ok\n"); /* We should log which one that is ok. This message doesn't really make sense in production use */
return 1;
#endif
}
int ast_ssl_setup(struct ast_tls_config *cfg)
{
return __ssl_setup(cfg, 0);
}
void ast_ssl_teardown(struct ast_tls_config *cfg)
{
#ifdef DO_SSL
if (cfg && cfg->ssl_ctx) {
SSL_CTX_free(cfg->ssl_ctx);
cfg->ssl_ctx = NULL;
}
#endif
}
/*!
* \internal
* \brief Connect a socket
*
* Attempt to connect to a given address for up to 'timeout' milliseconds. A negative
* timeout value equates to an infinite wait time.
*
* A -1 is returned on error, and an appropriate errno value is set based on the
* type of error.
*
* \param sockfd The socket file descriptor
* \param addr The address to connect to
* \param timeout How long, in milliseconds, to attempt to connect
*
* \return 0 if successfully connected, -1 otherwise
*/
static int socket_connect(int sockfd, const struct ast_sockaddr *addr, int timeout)
{
int optval = 0;
socklen_t optlen = sizeof(int);
errno = 0;
if (ast_connect(sockfd, addr)) {
int res;
/*
* A connect failure could mean things are still in progress.
* If so wait for it to complete.
*/
if (errno != EINPROGRESS) {
return -1;
}
while ((res = ast_wait_for_output(sockfd, timeout)) != 1) {
if (res == 0) {
errno = ETIMEDOUT;
return -1;
}
if (errno != EINTR) {
return -1;
}
}
}
/* Check the status to ensure it actually connected successfully */
if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, &optlen) < 0) {
return -1;
}
if (optval) {
errno = optval;
return -1;
}
return 0;
}
struct ast_tcptls_session_instance *ast_tcptls_client_start_timeout(
struct ast_tcptls_session_instance *tcptls_session, int timeout)
{
struct ast_tcptls_session_args *desc;
if (!(desc = tcptls_session->parent)) {
ao2_ref(tcptls_session, -1);
return NULL;
}
if (socket_connect(desc->accept_fd, &desc->remote_address, timeout)) {
ast_log(LOG_WARNING, "Unable to connect %s to %s: %s\n", desc->name,
ast_sockaddr_stringify(&desc->remote_address), strerror(errno));
ao2_ref(tcptls_session, -1);
return NULL;
}
ast_fd_clear_flags(desc->accept_fd, O_NONBLOCK);
if (desc->tls_cfg) {
desc->tls_cfg->enabled = 1;
__ssl_setup(desc->tls_cfg, 1);
}
return handle_tcptls_connection(tcptls_session);
}
struct ast_tcptls_session_instance *ast_tcptls_client_start(struct ast_tcptls_session_instance *tcptls_session)
{
return ast_tcptls_client_start_timeout(tcptls_session, -1);
}
struct ast_tcptls_session_instance *ast_tcptls_client_create(struct ast_tcptls_session_args *desc)
{
int fd, x = 1;
struct ast_tcptls_session_instance *tcptls_session = NULL;
/* Do nothing if nothing has changed */
if (!ast_sockaddr_cmp(&desc->old_address, &desc->remote_address)) {
ast_debug(1, "Nothing changed in %s\n", desc->name);
return NULL;
}
/* If we return early, there is no connection */
ast_sockaddr_setnull(&desc->old_address);
fd = desc->accept_fd = ast_socket_nonblock(ast_sockaddr_is_ipv6(&desc->remote_address) ?
AF_INET6 : AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (desc->accept_fd < 0) {
ast_log(LOG_ERROR, "Unable to allocate socket for %s: %s\n",
desc->name, strerror(errno));
return NULL;
}
/* if a local address was specified, bind to it so the connection will
originate from the desired address */
if (!ast_sockaddr_isnull(&desc->local_address) &&
!ast_sockaddr_is_any(&desc->local_address)) {
setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
if (ast_bind(desc->accept_fd, &desc->local_address)) {
ast_log(LOG_ERROR, "Unable to bind %s to %s: %s\n",
desc->name,
ast_sockaddr_stringify(&desc->local_address),
strerror(errno));
goto error;
}
}
tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor);
if (!tcptls_session) {
goto error;
}
tcptls_session->overflow_buf = ast_str_create(128);
if (!tcptls_session->overflow_buf) {
goto error;
}
tcptls_session->client = 1;
tcptls_session->stream = ast_iostream_from_fd(&fd);
if (!tcptls_session->stream) {
goto error;
}
/* From here on out, the iostream owns the accept_fd and it will take
* care of closing it when the iostream is closed */
tcptls_session->parent = desc;
tcptls_session->parent->worker_fn = NULL;
ast_sockaddr_copy(&tcptls_session->remote_address,
&desc->remote_address);
/* Set current info */
ast_sockaddr_copy(&desc->old_address, &desc->remote_address);
return tcptls_session;
error:
close(desc->accept_fd);
desc->accept_fd = -1;
ao2_cleanup(tcptls_session);
return NULL;
}
void ast_tcptls_server_start(struct ast_tcptls_session_args *desc)
{
int x = 1;
int tls_changed = 0;
int sd_socket;
if (desc->tls_cfg) {
char hash[41];
char *str = NULL;
struct stat st;
/* Store the hashes of the TLS certificate etc. */
if (stat(desc->tls_cfg->certfile, &st) || NULL == (str = ast_read_textfile(desc->tls_cfg->certfile))) {
memset(hash, 0, 41);
} else {
ast_sha1_hash(hash, str);
}
ast_free(str);
str = NULL;
memcpy(desc->tls_cfg->certhash, hash, 41);
if (stat(desc->tls_cfg->pvtfile, &st) || NULL == (str = ast_read_textfile(desc->tls_cfg->pvtfile))) {
memset(hash, 0, 41);
} else {
ast_sha1_hash(hash, str);
}
ast_free(str);
str = NULL;
memcpy(desc->tls_cfg->pvthash, hash, 41);
if (stat(desc->tls_cfg->cafile, &st) || NULL == (str = ast_read_textfile(desc->tls_cfg->cafile))) {
memset(hash, 0, 41);
} else {
ast_sha1_hash(hash, str);
}
ast_free(str);
str = NULL;
memcpy(desc->tls_cfg->cahash, hash, 41);
/* Check whether TLS configuration has changed */
if (!desc->old_tls_cfg) { /* No previous configuration */
tls_changed = 1;
desc->old_tls_cfg = ast_calloc(1, sizeof(*desc->old_tls_cfg));
} else if (memcmp(desc->tls_cfg->certhash, desc->old_tls_cfg->certhash, 41)) {
tls_changed = 1;
} else if (memcmp(desc->tls_cfg->pvthash, desc->old_tls_cfg->pvthash, 41)) {
tls_changed = 1;
} else if (strcmp(desc->tls_cfg->cipher, desc->old_tls_cfg->cipher)) {
tls_changed = 1;
} else if (memcmp(desc->tls_cfg->cahash, desc->old_tls_cfg->cahash, 41)) {
tls_changed = 1;
} else if (strcmp(desc->tls_cfg->capath, desc->old_tls_cfg->capath)) {
tls_changed = 1;
} else if (memcmp(&desc->tls_cfg->flags, &desc->old_tls_cfg->flags, sizeof(desc->tls_cfg->flags))) {
tls_changed = 1;
}
if (tls_changed) {
ast_debug(1, "Changed parameters for %s found\n", desc->name);
}
}
/* Do nothing if nothing has changed */
if (!tls_changed && !ast_sockaddr_cmp(&desc->old_address, &desc->local_address)) {
ast_debug(1, "Nothing changed in %s\n", desc->name);
return;
}
/* If we return early, there is no one listening */
ast_sockaddr_setnull(&desc->old_address);
/* Shutdown a running server if there is one */
if (desc->master != AST_PTHREADT_NULL) {
pthread_cancel(desc->master);
pthread_kill(desc->master, SIGURG);
pthread_join(desc->master, NULL);
}
sd_socket = ast_sd_get_fd(SOCK_STREAM, &desc->local_address);
if (sd_socket != -1) {
if (desc->accept_fd != sd_socket) {
if (desc->accept_fd != -1) {
close(desc->accept_fd);
}
desc->accept_fd = sd_socket;
}
goto systemd_socket_activation;
}
if (desc->accept_fd != -1) {
close(desc->accept_fd);
}
/* If there's no new server, stop here */
if (ast_sockaddr_isnull(&desc->local_address)) {
ast_debug(2, "Server disabled: %s\n", desc->name);
return;
}
desc->accept_fd = ast_socket_nonblock(ast_sockaddr_is_ipv6(&desc->local_address) ?
AF_INET6 : AF_INET, SOCK_STREAM, 0);
if (desc->accept_fd < 0) {
ast_log(LOG_ERROR, "Unable to allocate socket for %s: %s\n", desc->name, strerror(errno));
return;
}
setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
if (ast_bind(desc->accept_fd, &desc->local_address)) {
ast_log(LOG_ERROR, "Unable to bind %s to %s: %s\n",
desc->name,
ast_sockaddr_stringify(&desc->local_address),
strerror(errno));
goto error;
}
if (listen(desc->accept_fd, 10)) {
ast_log(LOG_ERROR, "Unable to listen for %s!\n", desc->name);
goto error;
}
systemd_socket_activation:
if (ast_pthread_create_background(&desc->master, NULL, desc->accept_fn, desc)) {
ast_log(LOG_ERROR, "Unable to launch thread for %s on %s: %s\n",
desc->name,
ast_sockaddr_stringify(&desc->local_address),
strerror(errno));
goto error;
}
/* Set current info */
ast_sockaddr_copy(&desc->old_address, &desc->local_address);
if (desc->old_tls_cfg) {
ast_free(desc->old_tls_cfg->certfile);
ast_free(desc->old_tls_cfg->pvtfile);
ast_free(desc->old_tls_cfg->cipher);
ast_free(desc->old_tls_cfg->cafile);
ast_free(desc->old_tls_cfg->capath);
desc->old_tls_cfg->certfile = ast_strdup(desc->tls_cfg->certfile);
desc->old_tls_cfg->pvtfile = ast_strdup(desc->tls_cfg->pvtfile);
desc->old_tls_cfg->cipher = ast_strdup(desc->tls_cfg->cipher);
desc->old_tls_cfg->cafile = ast_strdup(desc->tls_cfg->cafile);
desc->old_tls_cfg->capath = ast_strdup(desc->tls_cfg->capath);
memcpy(desc->old_tls_cfg->certhash, desc->tls_cfg->certhash, 41);
memcpy(desc->old_tls_cfg->pvthash, desc->tls_cfg->pvthash, 41);
memcpy(desc->old_tls_cfg->cahash, desc->tls_cfg->cahash, 41);
memcpy(&desc->old_tls_cfg->flags, &desc->tls_cfg->flags, sizeof(desc->old_tls_cfg->flags));
}
return;
error:
close(desc->accept_fd);
desc->accept_fd = -1;
}
void ast_tcptls_close_session_file(struct ast_tcptls_session_instance *tcptls_session)
{
if (tcptls_session->stream) {
ast_iostream_close(tcptls_session->stream);
tcptls_session->stream = NULL;
} else {
ast_debug(1, "ast_tcptls_close_session_file invoked on session instance without file or file descriptor\n");
}
}
void ast_tcptls_server_stop(struct ast_tcptls_session_args *desc)
{
if (desc->master != AST_PTHREADT_NULL) {
pthread_cancel(desc->master);
pthread_kill(desc->master, SIGURG);
pthread_join(desc->master, NULL);
desc->master = AST_PTHREADT_NULL;
}
if (desc->accept_fd != -1) {
close(desc->accept_fd);
}
desc->accept_fd = -1;
if (desc->old_tls_cfg) {
ast_free(desc->old_tls_cfg->certfile);
ast_free(desc->old_tls_cfg->pvtfile);
ast_free(desc->old_tls_cfg->cipher);
ast_free(desc->old_tls_cfg->cafile);
ast_free(desc->old_tls_cfg->capath);
ast_free(desc->old_tls_cfg);
desc->old_tls_cfg = NULL;
}
ast_debug(2, "Stopped server :: %s\n", desc->name);
}
int ast_tls_read_conf(struct ast_tls_config *tls_cfg, struct ast_tcptls_session_args *tls_desc, const char *varname, const char *value)
{
if (!strcasecmp(varname, "tlsenable") || !strcasecmp(varname, "sslenable")) {
tls_cfg->enabled = ast_true(value) ? 1 : 0;
} else if (!strcasecmp(varname, "tlscertfile") || !strcasecmp(varname, "sslcert") || !strcasecmp(varname, "tlscert")) {
ast_free(tls_cfg->certfile);
tls_cfg->certfile = ast_strdup(value);
} else if (!strcasecmp(varname, "tlsprivatekey") || !strcasecmp(varname, "sslprivatekey")) {
ast_free(tls_cfg->pvtfile);
tls_cfg->pvtfile = ast_strdup(value);
} else if (!strcasecmp(varname, "tlscipher") || !strcasecmp(varname, "sslcipher")) {
ast_free(tls_cfg->cipher);
tls_cfg->cipher = ast_strdup(value);
} else if (!strcasecmp(varname, "tlscafile")) {
ast_free(tls_cfg->cafile);
tls_cfg->cafile = ast_strdup(value);
} else if (!strcasecmp(varname, "tlscapath") || !strcasecmp(varname, "tlscadir")) {
ast_free(tls_cfg->capath);
tls_cfg->capath = ast_strdup(value);
} else if (!strcasecmp(varname, "tlsverifyclient")) {
ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_VERIFY_CLIENT);
} else if (!strcasecmp(varname, "tlsdontverifyserver")) {
ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_DONT_VERIFY_SERVER);
} else if (!strcasecmp(varname, "tlsbindaddr") || !strcasecmp(varname, "sslbindaddr")) {
if (ast_parse_arg(value, PARSE_ADDR, &tls_desc->local_address))
ast_log(LOG_ERROR, "Invalid %s '%s'\n", varname, value);
} else if (!strcasecmp(varname, "tlsclientmethod") || !strcasecmp(varname, "sslclientmethod")) {
if (!strcasecmp(value, "tlsv1")) {
ast_set_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
} else if (!strcasecmp(value, "sslv3")) {
ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
} else if (!strcasecmp(value, "sslv2")) {
ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
}
} else if (!strcasecmp(varname, "tlsservercipherorder")) {
ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_SERVER_CIPHER_ORDER);
} else if (!strcasecmp(varname, "tlsdisablev1")) {
ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_DISABLE_TLSV1);
} else if (!strcasecmp(varname, "tlsdisablev11")) {
ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_DISABLE_TLSV11);
} else if (!strcasecmp(varname, "tlsdisablev12")) {
ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_DISABLE_TLSV12);
} else {
return -1;
}
return 0;
}