Mon Oct 8 12:39:30 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)
 Set up an SSL server.
void ast_ssl_teardown (struct ast_tls_config *cfg)
 free resources used by an SSL server
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 307 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().

00308 {
00309 #ifndef DO_SSL
00310    cfg->enabled = 0;
00311    return 0;
00312 #else
00313    if (!cfg->enabled)
00314       return 0;
00315 
00316    SSL_load_error_strings();
00317    SSLeay_add_ssl_algorithms();
00318 
00319    /* Get rid of an old SSL_CTX since we're about to
00320     * allocate a new one
00321     */
00322    if (cfg->ssl_ctx) {
00323       SSL_CTX_free(cfg->ssl_ctx);
00324       cfg->ssl_ctx = NULL;
00325    }
00326 
00327    if (client) {
00328 #ifndef OPENSSL_NO_SSL2
00329       if (ast_test_flag(&cfg->flags, AST_SSL_SSLV2_CLIENT)) {
00330          cfg->ssl_ctx = SSL_CTX_new(SSLv2_client_method());
00331       } else
00332 #endif
00333       if (ast_test_flag(&cfg->flags, AST_SSL_SSLV3_CLIENT)) {
00334          cfg->ssl_ctx = SSL_CTX_new(SSLv3_client_method());
00335       } else if (ast_test_flag(&cfg->flags, AST_SSL_TLSV1_CLIENT)) {
00336          cfg->ssl_ctx = SSL_CTX_new(TLSv1_client_method());
00337       } else {
00338          /* SSLv23_client_method() sends SSLv2, this was the original
00339           * default for ssl clients before the option was given to
00340           * pick what protocol a client should use.  In order not
00341           * to break expected behavior it remains the default. */
00342          cfg->ssl_ctx = SSL_CTX_new(SSLv23_client_method());
00343       }
00344    } else {
00345       /* SSLv23_server_method() supports TLSv1, SSLv2, and SSLv3 inbound connections. */
00346       cfg->ssl_ctx = SSL_CTX_new(SSLv23_server_method());
00347    }
00348 
00349    if (!cfg->ssl_ctx) {
00350       ast_debug(1, "Sorry, SSL_CTX_new call returned null...\n");
00351       cfg->enabled = 0;
00352       return 0;
00353    }
00354    if (!ast_strlen_zero(cfg->certfile)) {
00355       char *tmpprivate = ast_strlen_zero(cfg->pvtfile) ? cfg->certfile : cfg->pvtfile;
00356       if (SSL_CTX_use_certificate_file(cfg->ssl_ctx, cfg->certfile, SSL_FILETYPE_PEM) == 0) {
00357          if (!client) {
00358             /* Clients don't need a certificate, but if its setup we can use it */
00359             ast_verb(0, "SSL error loading cert file. <%s>", cfg->certfile);
00360             sleep(2);
00361             cfg->enabled = 0;
00362             SSL_CTX_free(cfg->ssl_ctx);
00363             cfg->ssl_ctx = NULL;
00364             return 0;
00365          }
00366       }
00367       if ((SSL_CTX_use_PrivateKey_file(cfg->ssl_ctx, tmpprivate, SSL_FILETYPE_PEM) == 0) || (SSL_CTX_check_private_key(cfg->ssl_ctx) == 0 )) {
00368          if (!client) {
00369             /* Clients don't need a private key, but if its setup we can use it */
00370             ast_verb(0, "SSL error loading private key file. <%s>", tmpprivate);
00371             sleep(2);
00372             cfg->enabled = 0;
00373             SSL_CTX_free(cfg->ssl_ctx);
00374             cfg->ssl_ctx = NULL;
00375             return 0;
00376          }
00377       }
00378    }
00379    if (!ast_strlen_zero(cfg->cipher)) {
00380       if (SSL_CTX_set_cipher_list(cfg->ssl_ctx, cfg->cipher) == 0 ) {
00381          if (!client) {
00382             ast_verb(0, "SSL cipher error <%s>", cfg->cipher);
00383             sleep(2);
00384             cfg->enabled = 0;
00385             SSL_CTX_free(cfg->ssl_ctx);
00386             cfg->ssl_ctx = NULL;
00387             return 0;
00388          }
00389       }
00390    }
00391    if (!ast_strlen_zero(cfg->cafile) || !ast_strlen_zero(cfg->capath)) {
00392       if (SSL_CTX_load_verify_locations(cfg->ssl_ctx, S_OR(cfg->cafile, NULL), S_OR(cfg->capath,NULL)) == 0)
00393          ast_verb(0, "SSL CA file(%s)/path(%s) error\n", cfg->cafile, cfg->capath);
00394    }
00395 
00396    ast_verb(0, "SSL certificate ok\n");
00397    return 1;
00398 #endif
00399 }

int ast_ssl_setup ( struct ast_tls_config cfg  ) 

Set up an SSL server.

Parameters:
cfg Configuration for the SSL server
Return values:
1 Success
0 Failure

Definition at line 401 of file tcptls.c.

References __ssl_setup().

00402 {
00403    return __ssl_setup(cfg, 0);
00404 }

void ast_ssl_teardown ( struct ast_tls_config cfg  ) 

free resources used by an SSL server

Note:
This only needs to be called if ast_ssl_setup() was directly called first.
Parameters:
cfg Configuration for the SSL server

Definition at line 406 of file tcptls.c.

References ast_tls_config::ssl_ctx.

Referenced by unload_module().

00407 {
00408 #ifdef DO_SSL
00409    if (cfg->ssl_ctx) {
00410       SSL_CTX_free(cfg->ssl_ctx);
00411       cfg->ssl_ctx = NULL;
00412    }
00413 #endif
00414 }

struct ast_tcptls_session_instance* ast_tcptls_client_create ( struct ast_tcptls_session_args desc  ) 

Definition at line 453 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().

00454 {
00455    int x = 1;
00456    struct ast_tcptls_session_instance *tcptls_session = NULL;
00457 
00458    /* Do nothing if nothing has changed */
00459    if (!ast_sockaddr_cmp(&desc->old_address, &desc->remote_address)) {
00460       ast_debug(1, "Nothing changed in %s\n", desc->name);
00461       return NULL;
00462    }
00463 
00464    /* If we return early, there is no connection */
00465    ast_sockaddr_setnull(&desc->old_address);
00466 
00467    if (desc->accept_fd != -1)
00468       close(desc->accept_fd);
00469 
00470    desc->accept_fd = socket(ast_sockaddr_is_ipv6(&desc->remote_address) ?
00471              AF_INET6 : AF_INET, SOCK_STREAM, IPPROTO_TCP);
00472    if (desc->accept_fd < 0) {
00473       ast_log(LOG_WARNING, "Unable to allocate socket for %s: %s\n",
00474          desc->name, strerror(errno));
00475       return NULL;
00476    }
00477 
00478    /* if a local address was specified, bind to it so the connection will
00479       originate from the desired address */
00480    if (!ast_sockaddr_isnull(&desc->local_address)) {
00481       setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
00482       if (ast_bind(desc->accept_fd, &desc->local_address)) {
00483          ast_log(LOG_ERROR, "Unable to bind %s to %s: %s\n",
00484             desc->name,
00485             ast_sockaddr_stringify(&desc->local_address),
00486             strerror(errno));
00487          goto error;
00488       }
00489    }
00490 
00491    if (!(tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor)))
00492       goto error;
00493 
00494    ast_mutex_init(&tcptls_session->lock);
00495    tcptls_session->client = 1;
00496    tcptls_session->fd = desc->accept_fd;
00497    tcptls_session->parent = desc;
00498    tcptls_session->parent->worker_fn = NULL;
00499    ast_sockaddr_copy(&tcptls_session->remote_address,
00500            &desc->remote_address);
00501 
00502    /* Set current info */
00503    ast_sockaddr_copy(&desc->old_address, &desc->remote_address);
00504    return tcptls_session;
00505 
00506 error:
00507    close(desc->accept_fd);
00508    desc->accept_fd = -1;
00509    if (tcptls_session)
00510       ao2_ref(tcptls_session, -1);
00511    return NULL;
00512 }

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 416 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().

00417 {
00418    struct ast_tcptls_session_args *desc;
00419    int flags;
00420 
00421    if (!(desc = tcptls_session->parent)) {
00422       goto client_start_error;
00423    }
00424 
00425    if (ast_connect(desc->accept_fd, &desc->remote_address)) {
00426       ast_log(LOG_ERROR, "Unable to connect %s to %s: %s\n",
00427          desc->name,
00428          ast_sockaddr_stringify(&desc->remote_address),
00429          strerror(errno));
00430       goto client_start_error;
00431    }
00432 
00433    flags = fcntl(desc->accept_fd, F_GETFL);
00434    fcntl(desc->accept_fd, F_SETFL, flags & ~O_NONBLOCK);
00435 
00436    if (desc->tls_cfg) {
00437       desc->tls_cfg->enabled = 1;
00438       __ssl_setup(desc->tls_cfg, 1);
00439    }
00440 
00441    return handle_tcptls_connection(tcptls_session);
00442 
00443 client_start_error:
00444    if (desc) {
00445       close(desc->accept_fd);
00446       desc->accept_fd = -1;
00447    }
00448    ao2_ref(tcptls_session, -1);
00449    return NULL;
00450 
00451 }

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 583 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().

00584 {
00585    if (tcptls_session->f) {
00586       if (fclose(tcptls_session->f)) {
00587          ast_log(LOG_ERROR, "fclose() failed: %s\n", strerror(errno));
00588       }
00589       tcptls_session->f = NULL;
00590       tcptls_session->fd = -1;
00591    } else if (tcptls_session->fd != -1) {
00592       if (close(tcptls_session->fd)) {
00593          ast_log(LOG_ERROR, "close() failed: %s\n", strerror(errno));
00594       }
00595       tcptls_session->fd = -1;
00596    } else {
00597       ast_log(LOG_ERROR, "ast_tcptls_close_session_file invoked on session instance without file or file descriptor\n");
00598    }
00599 }

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

Definition at line 104 of file tcptls.c.

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

00105 {
00106    if (tcptls_session->fd == -1) {
00107       ast_log(LOG_ERROR, "server_read called with an fd of -1\n");
00108       errno = EIO;
00109       return -1;
00110    }
00111 
00112 #ifdef DO_SSL
00113    if (tcptls_session->ssl)
00114       return ssl_read(tcptls_session->ssl, buf, count);
00115 #endif
00116    return read(tcptls_session->fd, buf, count);
00117 }

void* ast_tcptls_server_root ( void *  data  ) 

Definition at line 256 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().

00257 {
00258    struct ast_tcptls_session_args *desc = data;
00259    int fd;
00260    struct ast_sockaddr addr;
00261    struct ast_tcptls_session_instance *tcptls_session;
00262    pthread_t launched;
00263 
00264    for (;;) {
00265       int i, flags;
00266 
00267       if (desc->periodic_fn)
00268          desc->periodic_fn(desc);
00269       i = ast_wait_for_input(desc->accept_fd, desc->poll_timeout);
00270       if (i <= 0)
00271          continue;
00272       fd = ast_accept(desc->accept_fd, &addr);
00273       if (fd < 0) {
00274          if ((errno != EAGAIN) && (errno != EINTR))
00275             ast_log(LOG_WARNING, "Accept failed: %s\n", strerror(errno));
00276          continue;
00277       }
00278       tcptls_session = ao2_alloc(sizeof(*tcptls_session), session_instance_destructor);
00279       if (!tcptls_session) {
00280          ast_log(LOG_WARNING, "No memory for new session: %s\n", strerror(errno));
00281          if (close(fd)) {
00282             ast_log(LOG_ERROR, "close() failed: %s\n", strerror(errno));
00283          }
00284          continue;
00285       }
00286 
00287       ast_mutex_init(&tcptls_session->lock);
00288 
00289       flags = fcntl(fd, F_GETFL);
00290       fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
00291       tcptls_session->fd = fd;
00292       tcptls_session->parent = desc;
00293       ast_sockaddr_copy(&tcptls_session->remote_address, &addr);
00294 
00295       tcptls_session->client = 0;
00296 
00297       /* This thread is now the only place that controls the single ref to tcptls_session */
00298       if (ast_pthread_create_detached_background(&launched, NULL, handle_tcptls_connection, tcptls_session)) {
00299          ast_log(LOG_WARNING, "Unable to launch helper thread: %s\n", strerror(errno));
00300          ast_tcptls_close_session_file(tcptls_session);
00301          ao2_ref(tcptls_session, -1);
00302       }
00303    }
00304    return NULL;
00305 }

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 514 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.

00515 {
00516    int flags;
00517    int x = 1;
00518 
00519    /* Do nothing if nothing has changed */
00520    if (!ast_sockaddr_cmp(&desc->old_address, &desc->local_address)) {
00521       ast_debug(1, "Nothing changed in %s\n", desc->name);
00522       return;
00523    }
00524 
00525    /* If we return early, there is no one listening */
00526    ast_sockaddr_setnull(&desc->old_address);
00527 
00528    /* Shutdown a running server if there is one */
00529    if (desc->master != AST_PTHREADT_NULL) {
00530       pthread_cancel(desc->master);
00531       pthread_kill(desc->master, SIGURG);
00532       pthread_join(desc->master, NULL);
00533    }
00534 
00535    if (desc->accept_fd != -1)
00536       close(desc->accept_fd);
00537 
00538    /* If there's no new server, stop here */
00539    if (ast_sockaddr_isnull(&desc->local_address)) {
00540       ast_debug(2, "Server disabled:  %s\n", desc->name);
00541       return;
00542    }
00543 
00544    desc->accept_fd = socket(ast_sockaddr_is_ipv6(&desc->local_address) ?
00545              AF_INET6 : AF_INET, SOCK_STREAM, 0);
00546    if (desc->accept_fd < 0) {
00547       ast_log(LOG_ERROR, "Unable to allocate socket for %s: %s\n", desc->name, strerror(errno));
00548       return;
00549    }
00550 
00551    setsockopt(desc->accept_fd, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
00552    if (ast_bind(desc->accept_fd, &desc->local_address)) {
00553       ast_log(LOG_ERROR, "Unable to bind %s to %s: %s\n",
00554          desc->name,
00555          ast_sockaddr_stringify(&desc->local_address),
00556          strerror(errno));
00557       goto error;
00558    }
00559    if (listen(desc->accept_fd, 10)) {
00560       ast_log(LOG_ERROR, "Unable to listen for %s!\n", desc->name);
00561       goto error;
00562    }
00563    flags = fcntl(desc->accept_fd, F_GETFL);
00564    fcntl(desc->accept_fd, F_SETFL, flags | O_NONBLOCK);
00565    if (ast_pthread_create_background(&desc->master, NULL, desc->accept_fn, desc)) {
00566       ast_log(LOG_ERROR, "Unable to launch thread for %s on %s: %s\n",
00567          desc->name,
00568          ast_sockaddr_stringify(&desc->local_address),
00569          strerror(errno));
00570       goto error;
00571    }
00572 
00573    /* Set current info */
00574    ast_sockaddr_copy(&desc->old_address, &desc->local_address);
00575 
00576    return;
00577 
00578 error:
00579    close(desc->accept_fd);
00580    desc->accept_fd = -1;
00581 }

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 601 of file tcptls.c.

References ast_debug, AST_PTHREADT_NULL, and desc.

Referenced by unload_module().

00602 {
00603    if (desc->master != AST_PTHREADT_NULL) {
00604       pthread_cancel(desc->master);
00605       pthread_kill(desc->master, SIGURG);
00606       pthread_join(desc->master, NULL);
00607       desc->master = AST_PTHREADT_NULL;
00608    }
00609    if (desc->accept_fd != -1)
00610       close(desc->accept_fd);
00611    desc->accept_fd = -1;
00612    ast_debug(2, "Stopped server :: %s\n", desc->name);
00613 }

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

Definition at line 119 of file tcptls.c.

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

00120 {
00121    if (tcptls_session->fd == -1) {
00122       ast_log(LOG_ERROR, "server_write called with an fd of -1\n");
00123       errno = EIO;
00124       return -1;
00125    }
00126 
00127 #ifdef DO_SSL
00128    if (tcptls_session->ssl)
00129       return ssl_write(tcptls_session->ssl, buf, count);
00130 #endif
00131    return write(tcptls_session->fd, buf, count);
00132 }

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 615 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().

00616 {
00617    if (!strcasecmp(varname, "tlsenable") || !strcasecmp(varname, "sslenable")) {
00618       tls_cfg->enabled = ast_true(value) ? 1 : 0;
00619    } else if (!strcasecmp(varname, "tlscertfile") || !strcasecmp(varname, "sslcert") || !strcasecmp(varname, "tlscert")) {
00620       ast_free(tls_cfg->certfile);
00621       tls_cfg->certfile = ast_strdup(value);
00622    } else if (!strcasecmp(varname, "tlsprivatekey") || !strcasecmp(varname, "sslprivatekey")) {
00623       ast_free(tls_cfg->pvtfile);
00624       tls_cfg->pvtfile = ast_strdup(value);
00625    } else if (!strcasecmp(varname, "tlscipher") || !strcasecmp(varname, "sslcipher")) {
00626       ast_free(tls_cfg->cipher);
00627       tls_cfg->cipher = ast_strdup(value);
00628    } else if (!strcasecmp(varname, "tlscafile")) {
00629       ast_free(tls_cfg->cafile);
00630       tls_cfg->cafile = ast_strdup(value);
00631    } else if (!strcasecmp(varname, "tlscapath") || !strcasecmp(varname, "tlscadir")) {
00632       ast_free(tls_cfg->capath);
00633       tls_cfg->capath = ast_strdup(value);
00634    } else if (!strcasecmp(varname, "tlsverifyclient")) {
00635       ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_VERIFY_CLIENT);
00636    } else if (!strcasecmp(varname, "tlsdontverifyserver")) {
00637       ast_set2_flag(&tls_cfg->flags, ast_true(value), AST_SSL_DONT_VERIFY_SERVER);
00638    } else if (!strcasecmp(varname, "tlsbindaddr") || !strcasecmp(varname, "sslbindaddr")) {
00639       if (ast_parse_arg(value, PARSE_ADDR, &tls_desc->local_address))
00640          ast_log(LOG_WARNING, "Invalid %s '%s'\n", varname, value);
00641    } else if (!strcasecmp(varname, "tlsclientmethod") || !strcasecmp(varname, "sslclientmethod")) {
00642       if (!strcasecmp(value, "tlsv1")) {
00643          ast_set_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
00644          ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
00645          ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
00646       } else if (!strcasecmp(value, "sslv3")) {
00647          ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
00648          ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
00649          ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
00650       } else if (!strcasecmp(value, "sslv2")) {
00651          ast_set_flag(&tls_cfg->flags, AST_SSL_SSLV2_CLIENT);
00652          ast_clear_flag(&tls_cfg->flags, AST_SSL_TLSV1_CLIENT);
00653          ast_clear_flag(&tls_cfg->flags, AST_SSL_SSLV3_CLIENT);
00654       }
00655    } else {
00656       return -1;
00657    }
00658 
00659    return 0;
00660 }

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 147 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().

00148 {
00149    struct ast_tcptls_session_instance *tcptls_session = data;
00150 #ifdef DO_SSL
00151    int (*ssl_setup)(SSL *) = (tcptls_session->client) ? SSL_connect : SSL_accept;
00152    int ret;
00153    char err[256];
00154 #endif
00155 
00156    /*
00157    * open a FILE * as appropriate.
00158    */
00159    if (!tcptls_session->parent->tls_cfg) {
00160       if ((tcptls_session->f = fdopen(tcptls_session->fd, "w+"))) {
00161          if(setvbuf(tcptls_session->f, NULL, _IONBF, 0)) {
00162             ast_tcptls_close_session_file(tcptls_session);
00163          }
00164       }
00165    }
00166 #ifdef DO_SSL
00167    else if ( (tcptls_session->ssl = SSL_new(tcptls_session->parent->tls_cfg->ssl_ctx)) ) {
00168       SSL_set_fd(tcptls_session->ssl, tcptls_session->fd);
00169       if ((ret = ssl_setup(tcptls_session->ssl)) <= 0) {
00170          ast_verb(2, "Problem setting up ssl connection: %s\n", ERR_error_string(ERR_get_error(), err));
00171       } else {
00172 #if defined(HAVE_FUNOPEN)  /* the BSD interface */
00173          tcptls_session->f = funopen(tcptls_session->ssl, ssl_read, ssl_write, NULL, ssl_close);
00174 
00175 #elif defined(HAVE_FOPENCOOKIE)  /* the glibc/linux interface */
00176          static const cookie_io_functions_t cookie_funcs = {
00177             ssl_read, ssl_write, NULL, ssl_close
00178          };
00179          tcptls_session->f = fopencookie(tcptls_session->ssl, "w+", cookie_funcs);
00180 #else
00181          /* could add other methods here */
00182          ast_debug(2, "no tcptls_session->f methods attempted!\n");
00183 #endif
00184          if ((tcptls_session->client && !ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_DONT_VERIFY_SERVER))
00185             || (!tcptls_session->client && ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_VERIFY_CLIENT))) {
00186             X509 *peer;
00187             long res;
00188             peer = SSL_get_peer_certificate(tcptls_session->ssl);
00189             if (!peer)
00190                ast_log(LOG_WARNING, "No peer SSL certificate\n");
00191             res = SSL_get_verify_result(tcptls_session->ssl);
00192             if (res != X509_V_OK)
00193                ast_log(LOG_ERROR, "Certificate did not verify: %s\n", X509_verify_cert_error_string(res));
00194             if (!ast_test_flag(&tcptls_session->parent->tls_cfg->flags, AST_SSL_IGNORE_COMMON_NAME)) {
00195                ASN1_STRING *str;
00196                unsigned char *str2;
00197                X509_NAME *name = X509_get_subject_name(peer);
00198                int pos = -1;
00199                int found = 0;
00200 
00201                for (;;) {
00202                   /* Walk the certificate to check all available "Common Name" */
00203                   /* XXX Probably should do a gethostbyname on the hostname and compare that as well */
00204                   pos = X509_NAME_get_index_by_NID(name, NID_commonName, pos);
00205                   if (pos < 0)
00206                      break;
00207                   str = X509_NAME_ENTRY_get_data(X509_NAME_get_entry(name, pos));
00208                   ASN1_STRING_to_UTF8(&str2, str);
00209                   if (str2) {
00210                      if (!strcasecmp(tcptls_session->parent->hostname, (char *) str2))
00211                         found = 1;
00212                      ast_debug(3, "SSL Common Name compare s1='%s' s2='%s'\n", tcptls_session->parent->hostname, str2);
00213                      OPENSSL_free(str2);
00214                   }
00215                   if (found)
00216                      break;
00217                }
00218                if (!found) {
00219                   ast_log(LOG_ERROR, "Certificate common name did not match (%s)\n", tcptls_session->parent->hostname);
00220                   if (peer) {
00221                      X509_free(peer);
00222                   }
00223                   ast_tcptls_close_session_file(tcptls_session);
00224                   ao2_ref(tcptls_session, -1);
00225                   return NULL;
00226                }
00227             }
00228             if (peer)
00229                X509_free(peer);
00230          }
00231       }
00232       if (!tcptls_session->f) /* no success opening descriptor stacking */
00233          SSL_free(tcptls_session->ssl);
00234    }
00235 #endif /* DO_SSL */
00236 
00237    if (!tcptls_session->f) {
00238       ast_tcptls_close_session_file(tcptls_session);
00239       ast_log(LOG_WARNING, "FILE * open failed!\n");
00240 #ifndef DO_SSL
00241       if (tcptls_session->parent->tls_cfg) {
00242          ast_log(LOG_WARNING, "Attempted a TLS connection without OpenSSL support.  This will not work!\n");
00243       }
00244 #endif
00245       ao2_ref(tcptls_session, -1);
00246       return NULL;
00247    }
00248 
00249    if (tcptls_session->parent->worker_fn) {
00250       return tcptls_session->parent->worker_fn(tcptls_session);
00251    } else {
00252       return tcptls_session;
00253    }
00254 }

static void session_instance_destructor ( void *  obj  )  [static]

Definition at line 134 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().

00135 {
00136    struct ast_tcptls_session_instance *i = obj;
00137    ast_mutex_destroy(&i->lock);
00138 }

static int ssl_close ( void *  cookie  )  [static]

Definition at line 81 of file tcptls.c.

References ast_log(), errno, and LOG_ERROR.

Referenced by handle_tcptls_connection().

00082 {
00083    int cookie_fd = SSL_get_fd(cookie);
00084    int ret;
00085    if (cookie_fd > -1) {
00086       /*
00087        * According to the TLS standard, it is acceptable for an application to only send its shutdown
00088        * alert and then close the underlying connection without waiting for the peer's response (this
00089        * way resources can be saved, as the process can already terminate or serve another connection).
00090        */
00091       if ((ret = SSL_shutdown(cookie)) < 0) {
00092          ast_log(LOG_ERROR, "SSL_shutdown() failed: %d\n", SSL_get_error(cookie, ret));
00093       }
00094       SSL_free(cookie);
00095       /* adding shutdown(2) here has no added benefit */
00096       if (close(cookie_fd)) {
00097          ast_log(LOG_ERROR, "close() failed: %s\n", strerror(errno));
00098       }
00099    }
00100    return 0;
00101 }

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 59 of file tcptls.c.

References ast_verb.

Referenced by ast_tcptls_server_read(), and handle_tcptls_connection().

00060 {
00061    int i = SSL_read(cookie, buf, len-1);
00062 #if 0
00063    if (i >= 0)
00064       buf[i] = '\0';
00065    ast_verb(0, "ssl read size %d returns %d <%s>\n", (int)len, i, buf);
00066 #endif
00067    return i;
00068 }

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

Definition at line 70 of file tcptls.c.

References ast_verb.

Referenced by ast_tcptls_server_write(), and handle_tcptls_connection().

00071 {
00072 #if 0
00073    char *s = alloca(len+1);
00074    strncpy(s, buf, len);
00075    s[len] = '\0';
00076    ast_verb(0, "ssl write size %d <%s>\n", (int)len, s);
00077 #endif
00078    return SSL_write(cookie, buf, len);
00079 }


Generated on Mon Oct 8 12:39:30 2012 for Asterisk - The Open Source Telephony Project by  doxygen 1.4.7