Mon Mar 19 11:30:56 2012

Asterisk developer's documentation


tcptls.c File Reference

Code to support TCP and TLS server/client. More...

#include "asterisk.h"
#include <fcntl.h>
#include <signal.h>
#include <sys/signal.h>
#include "asterisk/compat.h"
#include "asterisk/tcptls.h"
#include "asterisk/http.h"
#include "asterisk/utils.h"
#include "asterisk/strings.h"
#include "asterisk/options.h"
#include "asterisk/manager.h"
#include "asterisk/astobj2.h"

Go to the source code of this file.

Functions

static int __ssl_setup (struct ast_tls_config *cfg, int client)
int ast_ssl_setup (struct ast_tls_config *cfg)
ast_tcptls_session_instanceast_tcptls_client_create (struct ast_tcptls_session_args *desc)
ast_tcptls_session_instanceast_tcptls_client_start (struct ast_tcptls_session_instance *tcptls_session)
 attempts to connect and start tcptls session, on error the tcptls_session's ref count is decremented, fd and file are closed, and NULL is returned.
void ast_tcptls_close_session_file (struct ast_tcptls_session_instance *tcptls_session)
 Closes a tcptls session instance's file and/or file descriptor. The tcptls_session will be set to NULL and it's file descriptor will be set to -1 by this function.
HOOK_T ast_tcptls_server_read (struct ast_tcptls_session_instance *tcptls_session, void *buf, size_t count)
void * ast_tcptls_server_root (void *data)
void ast_tcptls_server_start (struct ast_tcptls_session_args *desc)
 This is a generic (re)start routine for a TCP server, which does the socket/bind/listen and starts a thread for handling accept().
void ast_tcptls_server_stop (struct ast_tcptls_session_args *desc)
 Shutdown a running server if there is one.
HOOK_T ast_tcptls_server_write (struct ast_tcptls_session_instance *tcptls_session, const void *buf, size_t count)
int ast_tls_read_conf (struct ast_tls_config *tls_cfg, struct ast_tcptls_session_args *tls_desc, const char *varname, const char *value)
 Used to parse conf files containing tls/ssl options.
static void * handle_tcptls_connection (void *data)
 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.
static void session_instance_destructor (void *obj)
static int ssl_close (void *cookie)
static HOOK_T ssl_read (void *cookie, char *buf, LEN_T len)
 replacement read/write functions for SSL support. We use wrappers rather than SSL_read/SSL_write directly so we can put in some debugging.
static HOOK_T ssl_write (void *cookie, const char *buf, LEN_T len)


Detailed Description

Code to support TCP and TLS server/client.

Author:
Luigi Rizzo

Brett Bryant <brettbryant@gmail.com>

Definition in file tcptls.c.


Function Documentation

static int __ssl_setup ( struct ast_tls_config cfg,
int  client 
) [static]

Definition at line 302 of file tcptls.c.

References ast_debug, AST_SSL_SSLV2_CLIENT, AST_SSL_SSLV3_CLIENT, AST_SSL_TLSV1_CLIENT, ast_strlen_zero(), ast_test_flag, ast_verb, ast_tls_config::cafile, ast_tls_config::capath, ast_tls_config::certfile, ast_tls_config::cipher, ast_tls_config::enabled, ast_tls_config::flags, ast_tls_config::pvtfile, S_OR, and ast_tls_config::ssl_ctx.

Referenced by ast_ssl_setup(), and ast_tcptls_client_start().

00303 {
00304 #ifndef DO_SSL
00305    cfg->enabled = 0;
00306    return 0;
00307 #else
00308    if (!cfg->enabled)
00309       return 0;
00310 
00311    SSL_load_error_strings();
00312    SSLeay_add_ssl_algorithms();
00313 
00314    if (client) {
00315 #ifndef OPENSSL_NO_SSL2
00316       if (ast_test_flag(&cfg->flags, AST_SSL_SSLV2_CLIENT)) {
00317          cfg->ssl_ctx = SSL_CTX_new(SSLv2_client_method());
00318       } else
00319 #endif
00320       if (ast_test_flag(&cfg->flags, AST_SSL_SSLV3_CLIENT)) {
00321          cfg->ssl_ctx = SSL_CTX_new(SSLv3_client_method());
00322       } else if (ast_test_flag(&cfg->flags, AST_SSL_TLSV1_CLIENT)) {
00323          cfg->ssl_ctx = SSL_CTX_new(TLSv1_client_method());
00324       } else {
00325          /* SSLv23_client_method() sends SSLv2, this was the original
00326           * default for ssl clients before the option was given to
00327           * pick what protocol a client should use.  In order not
00328           * to break expected behavior it remains the default. */
00329          cfg->ssl_ctx = SSL_CTX_new(SSLv23_client_method());
00330       }
00331    } else {
00332       /* SSLv23_server_method() supports TLSv1, SSLv2, and SSLv3 inbound connections. */
00333       cfg->ssl_ctx = SSL_CTX_new(SSLv23_server_method());
00334    }
00335 
00336    if (!cfg->ssl_ctx) {
00337       ast_debug(1, "Sorry, SSL_CTX_new call returned null...\n");
00338       cfg->enabled = 0;
00339       return 0;
00340    }
00341    if (!ast_strlen_zero(cfg->certfile)) {
00342       char *tmpprivate = ast_strlen_zero(cfg->pvtfile) ? cfg->certfile : cfg->pvtfile;
00343       if (SSL_CTX_use_certificate_file(cfg->ssl_ctx, cfg->certfile, SSL_FILETYPE_PEM) == 0) {
00344          if (!client) {
00345             /* Clients don't need a certificate, but if its setup we can use it */
00346             ast_verb(0, "SSL error loading cert file. <%s>", cfg->certfile);
00347             sleep(2);
00348             cfg->enabled = 0;
00349             return 0;
00350          }
00351       }
00352       if ((SSL_CTX_use_PrivateKey_file(cfg->ssl_ctx, tmpprivate, SSL_FILETYPE_PEM) == 0) || (SSL_CTX_check_private_key(cfg->ssl_ctx) == 0 )) {
00353          if (!client) {
00354             /* Clients don't need a private key, but if its setup we can use it */
00355             ast_verb(0, "SSL error loading private key file. <%s>", tmpprivate);
00356             sleep(2);
00357             cfg->enabled = 0;
00358             return 0;
00359          }
00360       }
00361    }
00362    if (!ast_strlen_zero(cfg->cipher)) {
00363       if (SSL_CTX_set_cipher_list(cfg->ssl_ctx, cfg->cipher) == 0 ) {
00364          if (!client) {
00365             ast_verb(0, "SSL cipher error <%s>", cfg->cipher);
00366             sleep(2);
00367             cfg->enabled = 0;
00368             return 0;
00369          }
00370       }
00371    }
00372    if (!ast_strlen_zero(cfg->cafile) || !ast_strlen_zero(cfg->capath)) {
00373       if (SSL_CTX_load_verify_locations(cfg->ssl_ctx, S_OR(cfg->cafile, NULL), S_OR(cfg->capath,NULL)) == 0)
00374          ast_verb(0, "SSL CA file(%s)/path(%s) error\n", cfg->cafile, cfg->capath);
00375    }
00376 
00377    ast_verb(0, "SSL certificate ok\n");
00378    return 1;
00379 #endif
00380 }

int ast_ssl_setup ( struct ast_tls_config cfg  ) 

Definition at line 382 of file tcptls.c.

References __ssl_setup().

00383 {
00384    return __ssl_setup(cfg, 0);
00385 }

struct ast_tcptls_session_instance* ast_tcptls_client_create ( struct ast_tcptls_session_args desc  ) 

Definition at line 424 of file tcptls.c.

References ao2_alloc, ao2_ref, ast_bind(), ast_debug, ast_log(), ast_mutex_init, ast_sockaddr_cmp(), ast_sockaddr_copy(), ast_sockaddr_is_ipv6(), ast_sockaddr_isnull(), ast_sockaddr_setnull(), ast_sockaddr_stringify(), desc, errno, LOG_ERROR, LOG_WARNING, and session_instance_destructor().

Referenced by sip_prepare_socket().

00425 {
00426    int x = 1;
00427    struct ast_tcptls_session_instance *tcptls_session = NULL;
00428 
00429    /* Do nothing if nothing has changed */
00430    if (!ast_sockaddr_cmp(&desc->old_address, &desc->remote_address)) {
00431       ast_debug(1, "Nothing changed in %s\n", desc->name);
00432       return NULL;
00433    }
00434 
00435    /* If we return early, there is no connection */
00436    ast_sockaddr_setnull(&desc->old_address);
00437 
00438    if (desc->accept_fd != -1)
00439       close(desc->accept_fd);
00440 
00441    desc->accept_fd = socket(ast_sockaddr_is_ipv6(&desc->remote_address) ?
00442              AF_INET6 : AF_INET, SOCK_STREAM, IPPROTO_TCP);
00443    if (desc->accept_fd < 0) {
00444       ast_log(LOG_WARNING, "Unable to allocate socket for %s: %s\n",
00445          desc->name, strerror(errno));
00446       return NULL;
00447    }
00448 
00449    /* if a local address was specified, bind to it so the connection will
00450       originate from the desired address */
00451    if (!ast_sockaddr_isnull(&desc->local_address)) {
00452       setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
00453       if (ast_bind(desc->accept_fd, &desc->local_address)) {
00454          ast_log(LOG_ERROR, "Unable to bind %s to %s: %s\n",
00455             desc->name,
00456             ast_sockaddr_stringify(&desc->local_address),
00457             strerror(errno));
00458          goto error;
00459       }
00460    }
00461 
00462    if (!(tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor)))
00463       goto error;
00464 
00465    ast_mutex_init(&tcptls_session->lock);
00466    tcptls_session->client = 1;
00467    tcptls_session->fd = desc->accept_fd;
00468    tcptls_session->parent = desc;
00469    tcptls_session->parent->worker_fn = NULL;
00470    ast_sockaddr_copy(&tcptls_session->remote_address,
00471            &desc->remote_address);
00472 
00473    /* Set current info */
00474    ast_sockaddr_copy(&desc->old_address, &desc->remote_address);
00475    return tcptls_session;
00476 
00477 error:
00478    close(desc->accept_fd);
00479    desc->accept_fd = -1;
00480    if (tcptls_session)
00481       ao2_ref(tcptls_session, -1);
00482    return NULL;
00483 }

struct ast_tcptls_session_instance* ast_tcptls_client_start ( struct ast_tcptls_session_instance tcptls_session  ) 

attempts to connect and start tcptls session, on error the tcptls_session's ref count is decremented, fd and file are closed, and NULL is returned.

Definition at line 387 of file tcptls.c.

References __ssl_setup(), ao2_ref, ast_connect(), ast_log(), ast_sockaddr_stringify(), desc, errno, handle_tcptls_connection(), LOG_ERROR, and ast_tcptls_session_instance::parent.

Referenced by _sip_tcp_helper_thread().

00388 {
00389    struct ast_tcptls_session_args *desc;
00390    int flags;
00391 
00392    if (!(desc = tcptls_session->parent)) {
00393       goto client_start_error;
00394    }
00395 
00396    if (ast_connect(desc->accept_fd, &desc->remote_address)) {
00397       ast_log(LOG_ERROR, "Unable to connect %s to %s: %s\n",
00398          desc->name,
00399          ast_sockaddr_stringify(&desc->remote_address),
00400          strerror(errno));
00401       goto client_start_error;
00402    }
00403 
00404    flags = fcntl(desc->accept_fd, F_GETFL);
00405    fcntl(desc->accept_fd, F_SETFL, flags & ~O_NONBLOCK);
00406 
00407    if (desc->tls_cfg) {
00408       desc->tls_cfg->enabled = 1;
00409       __ssl_setup(desc->tls_cfg, 1);
00410    }
00411 
00412    return handle_tcptls_connection(tcptls_session);
00413 
00414 client_start_error:
00415    close(desc->accept_fd);
00416    desc->accept_fd = -1;
00417    if (tcptls_session) {
00418       ao2_ref(tcptls_session, -1);
00419    }
00420    return NULL;
00421 
00422 }

void ast_tcptls_close_session_file ( struct ast_tcptls_session_instance tcptls_session  ) 

Closes a tcptls session instance's file and/or file descriptor. The tcptls_session will be set to NULL and it's file descriptor will be set to -1 by this function.

Definition at line 554 of file tcptls.c.

References ast_log(), errno, ast_tcptls_session_instance::f, ast_tcptls_session_instance::fd, and LOG_ERROR.

Referenced by ast_tcptls_server_root(), handle_tcptls_connection(), and sip_prepare_socket().

00555 {
00556    if (tcptls_session->f) {
00557       if (fclose(tcptls_session->f)) {
00558          ast_log(LOG_ERROR, "fclose() failed: %s\n", strerror(errno));
00559       }
00560       tcptls_session->f = NULL;
00561       tcptls_session->fd = -1;
00562    } else if (tcptls_session->fd != -1) {
00563       if (close(tcptls_session->fd)) {
00564          ast_log(LOG_ERROR, "close() failed: %s\n", strerror(errno));
00565       }
00566       tcptls_session->fd = -1;
00567    } else {
00568       ast_log(LOG_ERROR, "ast_tcptls_close_session_file invoked on session instance without file or file descriptor\n");
00569    }
00570 }

HOOK_T ast_tcptls_server_read ( struct ast_tcptls_session_instance tcptls_session,
void *  buf,
size_t  count 
)

Definition at line 100 of file tcptls.c.

References ast_log(), errno, ast_tcptls_session_instance::fd, LOG_ERROR, ast_tcptls_session_instance::ssl, and ssl_read().

00101 {
00102    if (tcptls_session->fd == -1) {
00103       ast_log(LOG_ERROR, "server_read called with an fd of -1\n");
00104       errno = EIO;
00105       return -1;
00106    }
00107 
00108 #ifdef DO_SSL
00109    if (tcptls_session->ssl)
00110       return ssl_read(tcptls_session->ssl, buf, count);
00111 #endif
00112    return read(tcptls_session->fd, buf, count);
00113 }

void* ast_tcptls_server_root ( void *  data  ) 

Definition at line 251 of file tcptls.c.

References ao2_alloc, ao2_ref, ast_accept(), ast_log(), ast_mutex_init, ast_pthread_create_detached_background, ast_sockaddr_copy(), ast_tcptls_close_session_file(), ast_wait_for_input(), desc, errno, handle_tcptls_connection(), LOG_ERROR, LOG_WARNING, and session_instance_destructor().

00252 {
00253    struct ast_tcptls_session_args *desc = data;
00254    int fd;
00255    struct ast_sockaddr addr;
00256    struct ast_tcptls_session_instance *tcptls_session;
00257    pthread_t launched;
00258 
00259    for (;;) {
00260       int i, flags;
00261 
00262       if (desc->periodic_fn)
00263          desc->periodic_fn(desc);
00264       i = ast_wait_for_input(desc->accept_fd, desc->poll_timeout);
00265       if (i <= 0)
00266          continue;
00267       fd = ast_accept(desc->accept_fd, &addr);
00268       if (fd < 0) {
00269          if ((errno != EAGAIN) && (errno != EINTR))
00270             ast_log(LOG_WARNING, "Accept failed: %s\n", strerror(errno));
00271          continue;
00272       }
00273       tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor);
00274       if (!tcptls_session) {
00275          ast_log(LOG_WARNING, "No memory for new session: %s\n", strerror(errno));
00276          if (close(fd)) {
00277             ast_log(LOG_ERROR, "close() failed: %s\n", strerror(errno));
00278          }
00279          continue;
00280       }
00281 
00282       ast_mutex_init(&tcptls_session->lock);
00283 
00284       flags = fcntl(fd, F_GETFL);
00285       fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
00286       tcptls_session->fd = fd;
00287       tcptls_session->parent = desc;
00288       ast_sockaddr_copy(&tcptls_session->remote_address, &addr);
00289 
00290       tcptls_session->client = 0;
00291 
00292       /* This thread is now the only place that controls the single ref to tcptls_session */
00293       if (ast_pthread_create_detached_background(&launched, NULL, handle_tcptls_connection, tcptls_session)) {
00294          ast_log(LOG_WARNING, "Unable to launch helper thread: %s\n", strerror(errno));
00295          ast_tcptls_close_session_file(tcptls_session);
00296          ao2_ref(tcptls_session, -1);
00297       }
00298    }
00299    return NULL;
00300 }

void ast_tcptls_server_start ( struct ast_tcptls_session_args desc  ) 

This is a generic (re)start routine for a TCP server, which does the socket/bind/listen and starts a thread for handling accept().

Version:
1.6.1 changed desc parameter to be of ast_tcptls_session_args type

Definition at line 485 of file tcptls.c.

References ast_bind(), ast_debug, ast_log(), ast_pthread_create_background, AST_PTHREADT_NULL, ast_sockaddr_cmp(), ast_sockaddr_copy(), ast_sockaddr_is_ipv6(), ast_sockaddr_isnull(), ast_sockaddr_setnull(), ast_sockaddr_stringify(), desc, errno, and LOG_ERROR.

00486 {
00487    int flags;
00488    int x = 1;
00489 
00490    /* Do nothing if nothing has changed */
00491    if (!ast_sockaddr_cmp(&desc->old_address, &desc->local_address)) {
00492       ast_debug(1, "Nothing changed in %s\n", desc->name);
00493       return;
00494    }
00495 
00496    /* If we return early, there is no one listening */
00497    ast_sockaddr_setnull(&desc->old_address);
00498 
00499    /* Shutdown a running server if there is one */
00500    if (desc->master != AST_PTHREADT_NULL) {
00501       pthread_cancel(desc->master);
00502       pthread_kill(desc->master, SIGURG);
00503       pthread_join(desc->master, NULL);
00504    }
00505 
00506    if (desc->accept_fd != -1)
00507       close(desc->accept_fd);
00508 
00509    /* If there's no new server, stop here */
00510    if (ast_sockaddr_isnull(&desc->local_address)) {
00511       ast_debug(2, "Server disabled:  %s\n", desc->name);
00512       return;
00513    }
00514 
00515    desc->accept_fd = socket(ast_sockaddr_is_ipv6(&desc->local_address) ?
00516              AF_INET6 : AF_INET, SOCK_STREAM, 0);
00517    if (desc->accept_fd < 0) {
00518       ast_log(LOG_ERROR, "Unable to allocate socket for %s: %s\n", desc->name, strerror(errno));
00519       return;
00520    }
00521 
00522    setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
00523    if (ast_bind(desc->accept_fd, &desc->local_address)) {
00524       ast_log(LOG_ERROR, "Unable to bind %s to %s: %s\n",
00525          desc->name,
00526          ast_sockaddr_stringify(&desc->local_address),
00527          strerror(errno));
00528       goto error;
00529    }
00530    if (listen(desc->accept_fd, 10)) {
00531       ast_log(LOG_ERROR, "Unable to listen for %s!\n", desc->name);
00532       goto error;
00533    }
00534    flags = fcntl(desc->accept_fd, F_GETFL);
00535    fcntl(desc->accept_fd, F_SETFL, flags | O_NONBLOCK);
00536    if (ast_pthread_create_background(&desc->master, NULL, desc->accept_fn, desc)) {
00537       ast_log(LOG_ERROR, "Unable to launch thread for %s on %s: %s\n",
00538          desc->name,
00539          ast_sockaddr_stringify(&desc->local_address),
00540          strerror(errno));
00541       goto error;
00542    }
00543 
00544    /* Set current info */
00545    ast_sockaddr_copy(&desc->old_address, &desc->local_address);
00546 
00547    return;
00548 
00549 error:
00550    close(desc->accept_fd);
00551    desc->accept_fd = -1;
00552 }

void ast_tcptls_server_stop ( struct ast_tcptls_session_args desc  ) 

Shutdown a running server if there is one.

Version:
1.6.1 changed desc parameter to be of ast_tcptls_session_args type

Definition at line 572 of file tcptls.c.

References ast_debug, AST_PTHREADT_NULL, and desc.

Referenced by unload_module().

00573 {
00574    if (desc->master != AST_PTHREADT_NULL) {
00575       pthread_cancel(desc->master);
00576       pthread_kill(desc->master, SIGURG);
00577       pthread_join(desc->master, NULL);
00578       desc->master = AST_PTHREADT_NULL;
00579    }
00580    if (desc->accept_fd != -1)
00581       close(desc->accept_fd);
00582    desc->accept_fd = -1;
00583    ast_debug(2, "Stopped server :: %s\n", desc->name);
00584 }

HOOK_T ast_tcptls_server_write ( struct ast_tcptls_session_instance tcptls_session,
const void *  buf,
size_t  count 
)

Definition at line 115 of file tcptls.c.

References ast_log(), errno, ast_tcptls_session_instance::fd, LOG_ERROR, ast_tcptls_session_instance::ssl, and ssl_write().

00116 {
00117    if (tcptls_session->fd == -1) {
00118       ast_log(LOG_ERROR, "server_write called with an fd of -1\n");
00119       errno = EIO;
00120       return -1;
00121    }
00122 
00123 #ifdef DO_SSL
00124    if (tcptls_session->ssl)
00125       return ssl_write(tcptls_session->ssl, buf, count);
00126 #endif
00127    return write(tcptls_session->fd, buf, count);
00128 }

int ast_tls_read_conf ( struct ast_tls_config tls_cfg,
struct ast_tcptls_session_args tls_desc,
const char *  varname,
const char *  value 
)

Used to parse conf files containing tls/ssl options.

Definition at line 586 of file tcptls.c.

References ast_clear_flag, ast_free, ast_log(), ast_parse_arg(), ast_set2_flag, ast_set_flag, AST_SSL_DONT_VERIFY_SERVER, AST_SSL_SSLV2_CLIENT, AST_SSL_SSLV3_CLIENT, AST_SSL_TLSV1_CLIENT, AST_SSL_VERIFY_CLIENT, ast_strdup, ast_true(), ast_tls_config::cafile, ast_tls_config::capath, ast_tls_config::certfile, ast_tls_config::cipher, ast_tls_config::enabled, ast_tls_config::flags, ast_tcptls_session_args::local_address, LOG_WARNING, PARSE_ADDR, and ast_tls_config::pvtfile.

Referenced by __ast_http_load(), __init_manager(), and reload_config().

00587 {
00588    if (!strcasecmp(varname, "tlsenable") || !strcasecmp(varname, "sslenable")) {
00589       tls_cfg->enabled = ast_true(value) ? 1 : 0;
00590    } else if (!strcasecmp(varname, "tlscertfile") || !strcasecmp(varname, "sslcert") || !strcasecmp(varname, "tlscert")) {
00591       ast_free(tls_cfg->certfile);
00592       tls_cfg->certfile = ast_strdup(value);
00593    } else if (!strcasecmp(varname, "tlsprivatekey") || !strcasecmp(varname, "sslprivatekey")) {
00594       ast_free(tls_cfg->pvtfile);
00595       tls_cfg->pvtfile = ast_strdup(value);
00596    } else if (!strcasecmp(varname, "tlscipher") || !strcasecmp(varname, "sslcipher")) {
00597       ast_free(tls_cfg->cipher);
00598       tls_cfg->cipher = ast_strdup(value);
00599    } else if (!strcasecmp(varname, "tlscafile")) {
00600       ast_free(tls_cfg->cafile);
00601       tls_cfg->cafile = ast_strdup(value);
00602    } else if (!strcasecmp(varname, "tlscapath") || !strcasecmp(varname, "tlscadir")) {
00603       ast_free(tls_cfg->capath);
00604       tls_cfg->capath = ast_strdup(value);
00605    } else if (!strcasecmp(varname, "tlsverifyclient")) {
00606       ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_VERIFY_CLIENT);
00607    } else if (!strcasecmp(varname, "tlsdontverifyserver")) {
00608       ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_DONT_VERIFY_SERVER);
00609    } else if (!strcasecmp(varname, "tlsbindaddr") || !strcasecmp(varname, "sslbindaddr")) {
00610       if (ast_parse_arg(value, PARSE_ADDR, &tls_desc->local_address))
00611          ast_log(LOG_WARNING, "Invalid %s '%s'\n", varname, value);
00612    } else if (!strcasecmp(varname, "tlsclientmethod") || !strcasecmp(varname, "sslclientmethod")) {
00613       if (!strcasecmp(value, "tlsv1")) {
00614          ast_set_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
00615          ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
00616          ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
00617       } else if (!strcasecmp(value, "sslv3")) {
00618          ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
00619          ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
00620          ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
00621       } else if (!strcasecmp(value, "sslv2")) {
00622          ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
00623          ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
00624          ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
00625       }
00626    } else {
00627       return -1;
00628    }
00629 
00630    return 0;
00631 }

static void* handle_tcptls_connection ( void *  data  )  [static]

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

Definition at line 143 of file tcptls.c.

References ao2_ref, ast_debug, ast_log(), AST_SSL_DONT_VERIFY_SERVER, AST_SSL_IGNORE_COMMON_NAME, AST_SSL_VERIFY_CLIENT, ast_tcptls_close_session_file(), ast_test_flag, ast_verb, ast_tcptls_session_instance::client, ast_tcptls_session_instance::f, ast_tcptls_session_instance::fd, ast_tls_config::flags, ast_tcptls_session_args::hostname, LOG_ERROR, LOG_WARNING, name, ast_tcptls_session_instance::parent, ast_tcptls_session_instance::ssl, ssl_close(), ast_tls_config::ssl_ctx, ssl_read(), ssl_write(), str, ast_tcptls_session_args::tls_cfg, and ast_tcptls_session_args::worker_fn.

Referenced by ast_tcptls_client_start(), and ast_tcptls_server_root().

00144 {
00145    struct ast_tcptls_session_instance *tcptls_session = data;
00146 #ifdef DO_SSL
00147    int (*ssl_setup)(SSL *) = (tcptls_session->client) ? SSL_connect : SSL_accept;
00148    int ret;
00149    char err[256];
00150 #endif
00151 
00152    /*
00153    * open a FILE * as appropriate.
00154    */
00155    if (!tcptls_session->parent->tls_cfg) {
00156       if ((tcptls_session->f = fdopen(tcptls_session->fd, "w+"))) {
00157          if(setvbuf(tcptls_session->f, NULL, _IONBF, 0)) {
00158             ast_tcptls_close_session_file(tcptls_session);
00159          }
00160       }
00161    }
00162 #ifdef DO_SSL
00163    else if ( (tcptls_session->ssl = SSL_new(tcptls_session->parent->tls_cfg->ssl_ctx)) ) {
00164       SSL_set_fd(tcptls_session->ssl, tcptls_session->fd);
00165       if ((ret = ssl_setup(tcptls_session->ssl)) <= 0) {
00166          ast_verb(2, "Problem setting up ssl connection: %s\n", ERR_error_string(ERR_get_error(), err));
00167       } else {
00168 #if defined(HAVE_FUNOPEN)  /* the BSD interface */
00169          tcptls_session->f = funopen(tcptls_session->ssl, ssl_read, ssl_write, NULL, ssl_close);
00170 
00171 #elif defined(HAVE_FOPENCOOKIE)  /* the glibc/linux interface */
00172          static const cookie_io_functions_t cookie_funcs = {
00173             ssl_read, ssl_write, NULL, ssl_close
00174          };
00175          tcptls_session->f = fopencookie(tcptls_session->ssl, "w+", cookie_funcs);
00176 #else
00177          /* could add other methods here */
00178          ast_debug(2, "no tcptls_session->f methods attempted!");
00179 #endif
00180          if ((tcptls_session->client && !ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_DONT_VERIFY_SERVER))
00181             || (!tcptls_session->client && ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_VERIFY_CLIENT))) {
00182             X509 *peer;
00183             long res;
00184             peer = SSL_get_peer_certificate(tcptls_session->ssl);
00185             if (!peer)
00186                ast_log(LOG_WARNING, "No peer SSL certificate\n");
00187             res = SSL_get_verify_result(tcptls_session->ssl);
00188             if (res != X509_V_OK)
00189                ast_log(LOG_ERROR, "Certificate did not verify: %s\n", X509_verify_cert_error_string(res));
00190             if (!ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_IGNORE_COMMON_NAME)) {
00191                ASN1_STRING *str;
00192                unsigned char *str2;
00193                X509_NAME *name = X509_get_subject_name(peer);
00194                int pos = -1;
00195                int found = 0;
00196 
00197                for (;;) {
00198                   /* Walk the certificate to check all available "Common Name" */
00199                   /* XXX Probably should do a gethostbyname on the hostname and compare that as well */
00200                   pos = X509_NAME_get_index_by_NID(name, NID_commonName, pos);
00201                   if (pos < 0)
00202                      break;
00203                   str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(name, pos));
00204                   ASN1_STRING_to_UTF8(&str2, str);
00205                   if (str2) {
00206                      if (!strcasecmp(tcptls_session->parent->hostname, (char *) str2))
00207                         found = 1;
00208                      ast_debug(3, "SSL Common Name compare s1='%s' s2='%s'\n", tcptls_session->parent->hostname, str2);
00209                      OPENSSL_free(str2);
00210                   }
00211                   if (found)
00212                      break;
00213                }
00214                if (!found) {
00215                   ast_log(LOG_ERROR, "Certificate common name did not match (%s)\n", tcptls_session->parent->hostname);
00216                   if (peer) {
00217                      X509_free(peer);
00218                   }
00219                   ast_tcptls_close_session_file(tcptls_session);
00220                   ao2_ref(tcptls_session, -1);
00221                   return NULL;
00222                }
00223             }
00224             if (peer)
00225                X509_free(peer);
00226          }
00227       }
00228       if (!tcptls_session->f) /* no success opening descriptor stacking */
00229          SSL_free(tcptls_session->ssl);
00230    }
00231 #endif /* DO_SSL */
00232 
00233    if (!tcptls_session->f) {
00234       ast_tcptls_close_session_file(tcptls_session);
00235       ast_log(LOG_WARNING, "FILE * open failed!\n");
00236 #ifndef DO_SSL
00237       if (tcptls_session->parent->tls_cfg) {
00238          ast_log(LOG_WARNING, "Attempted a TLS connection without OpenSSL support.  This will not work!\n");
00239       }
00240 #endif
00241       ao2_ref(tcptls_session, -1);
00242       return NULL;
00243    }
00244 
00245    if (tcptls_session && tcptls_session->parent->worker_fn)
00246       return tcptls_session->parent->worker_fn(tcptls_session);
00247    else
00248       return tcptls_session;
00249 }

static void session_instance_destructor ( void *  obj  )  [static]

Definition at line 130 of file tcptls.c.

References ast_mutex_destroy, and ast_tcptls_session_instance::lock.

Referenced by ast_tcptls_client_create(), and ast_tcptls_server_root().

00131 {
00132    struct ast_tcptls_session_instance *i = obj;
00133    ast_mutex_destroy(&i->lock);
00134 }

static int ssl_close ( void *  cookie  )  [static]

Definition at line 77 of file tcptls.c.

References ast_log(), errno, and LOG_ERROR.

Referenced by handle_tcptls_connection().

00078 {
00079    int cookie_fd = SSL_get_fd(cookie);
00080    int ret;
00081    if (cookie_fd > -1) {
00082       /*
00083        * According to the TLS standard, it is acceptable for an application to only send its shutdown
00084        * alert and then close the underlying connection without waiting for the peer's response (this
00085        * way resources can be saved, as the process can already terminate or serve another connection).
00086        */
00087       if ((ret = SSL_shutdown(cookie)) < 0) {
00088          ast_log(LOG_ERROR, "SSL_shutdown() failed: %d\n", SSL_get_error(cookie, ret));
00089       }
00090       SSL_free(cookie);
00091       /* adding shutdown(2) here has no added benefit */
00092       if (close(cookie_fd)) {
00093          ast_log(LOG_ERROR, "close() failed: %s\n", strerror(errno));
00094       }
00095    }
00096    return 0;
00097 }

static HOOK_T ssl_read ( void *  cookie,
char *  buf,
LEN_T  len 
) [static]

replacement read/write functions for SSL support. We use wrappers rather than SSL_read/SSL_write directly so we can put in some debugging.

Definition at line 55 of file tcptls.c.

References ast_verb.

Referenced by ast_tcptls_server_read(), and handle_tcptls_connection().

00056 {
00057    int i = SSL_read(cookie, buf, len-1);
00058 #if 0
00059    if (i >= 0)
00060       buf[i] = '\0';
00061    ast_verb(0, "ssl read size %d returns %d <%s>\n", (int)len, i, buf);
00062 #endif
00063    return i;
00064 }

static HOOK_T ssl_write ( void *  cookie,
const char *  buf,
LEN_T  len 
) [static]

Definition at line 66 of file tcptls.c.

References ast_verb.

Referenced by ast_tcptls_server_write(), and handle_tcptls_connection().

00067 {
00068 #if 0
00069    char *s = alloca(len+1);
00070    strncpy(s, buf, len);
00071    s[len] = '\0';
00072    ast_verb(0, "ssl write size %d <%s>\n", (int)len, s);
00073 #endif
00074    return SSL_write(cookie, buf, len);
00075 }


Generated on Mon Mar 19 11:30:56 2012 for Asterisk - The Open Source Telephony Project by  doxygen 1.4.7