src/network/tls.c

   1 /*****************************************************************************
   2  * tls.c
   3  *****************************************************************************
   4  * Copyright © 2004-2007 Rémi Denis-Courmont
   5  * $Id$
   6  *
   7  * Authors: Rémi Denis-Courmont <rem # videolan.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  17  * GNU Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /**
  25  * @file
  26  * libvlc interface to the Transport Layer Security (TLS) plugins.
  27  */
  28
  29 #ifdef HAVE_CONFIG_H
  30 # include "config.h"
  31 #endif
  32
  33 #include <vlc_common.h>
  34 #include "libvlc.h"
  35
  36 #include <vlc_tls.h>
  37 #include <vlc_modules.h>
  38
  39 /**
  40  * Allocates a whole server's TLS credentials.
  41  *
  42  * @param cert_path required (Unicode) path to an x509 certificate,
  43  *                  if NULL, anonymous key exchange will be used.
  44  * @param key_path (UTF-8) path to the PKCS private key for the certificate,
  45  *                 if NULL; cert_path will be used.
  46  *
  47  * @return NULL on error.
  48  */
  49 vlc_tls_creds_t *
  50 vlc_tls_ServerCreate (vlc_object_t *obj, const char *cert_path,
  51                       const char *key_path)
  52 {
  53     vlc_tls_creds_t *srv = vlc_custom_create (obj, sizeof (*srv), "tls creds");
  54     if (unlikely(srv == NULL))
  55         return NULL;
  56
  57     var_Create (srv, "tls-x509-cert", VLC_VAR_STRING);
  58     var_Create (srv, "tls-x509-key", VLC_VAR_STRING);
  59
  60     if (cert_path != NULL)
  61     {
  62         var_SetString (srv, "tls-x509-cert", cert_path);
  63
  64         if (key_path == NULL)
  65             key_path = cert_path;
  66         var_SetString (srv, "tls-x509-key", key_path);
  67     }
  68
  69     srv->module = module_need (srv, "tls server", NULL, false );
  70     if (srv->module == NULL)
  71     {
  72         msg_Err (srv, "TLS server plugin not available");
  73         vlc_object_release (srv);
  74         return NULL;
  75     }
  76
  77     msg_Dbg (srv, "TLS server plugin initialized");
  78     return srv;
  79 }
  80
  81
  82 /**
  83  * Releases data allocated with vlc_tls_ServerCreate().
  84  * @param srv TLS server object to be destroyed, or NULL
  85  */
  86 void vlc_tls_ServerDelete (vlc_tls_creds_t *srv)
  87 {
  88     if (srv == NULL)
  89         return;
  90
  91     module_unneed (srv, srv->module);
  92     vlc_object_release (srv);
  93 }
  94
  95
  96 /**
  97  * Adds one or more certificate authorities from a file.
  98  * @return -1 on error, 0 on success.
  99  */
 100 int vlc_tls_ServerAddCA (vlc_tls_creds_t *srv, const char *path)
 101 {
 102     return srv->add_CA (srv, path);
 103 }
 104
 105
 106 /**
 107  * Adds one or more certificate revocation list from a file.
 108  * @return -1 on error, 0 on success.
 109  */
 110 int vlc_tls_ServerAddCRL (vlc_tls_creds_t *srv, const char *path)
 111 {
 112     return srv->add_CRL (srv, path);
 113 }
 114
 115
 116 vlc_tls_t *vlc_tls_ServerSessionCreate (vlc_tls_creds_t *srv, int fd)
 117 {
 118     return srv->open (srv, fd);
 119 }
 120
 121
 122 void vlc_tls_ServerSessionDelete (vlc_tls_t *ses)
 123 {
 124     ses->u.close (ses);
 125 }
 126
 127
 128 int vlc_tls_ServerSessionHandshake (vlc_tls_t *ses)
 129 {
 130     int val = ses->handshake (ses);
 131     if (val < 0)
 132         vlc_tls_ServerSessionDelete (ses);
 133     return val;
 134 }
 135
 136
 137 /*** TLS client session ***/
 138 /* TODO: cache certificates for the whole VLC instance lifetime */
 139
 140 static int tls_client_start(void *func, va_list ap)
 141 {
 142     int (*activate) (vlc_tls_t *, int fd, const char *hostname) = func;
 143     vlc_tls_t *session = va_arg (ap, vlc_tls_t *);
 144     int fd = va_arg (ap, int);
 145     const char *hostname = va_arg (ap, const char *);
 146
 147     return activate (session, fd, hostname);
 148 }
 149
 150 static void tls_client_stop(void *func, va_list ap)
 151 {
 152     void (*deactivate) (vlc_tls_t *) = func;
 153     vlc_tls_t *session = va_arg (ap, vlc_tls_t *);
 154
 155     deactivate (session);
 156 }
 157
 158 /**
 159  * Allocates a client's TLS credentials and shakes hands through the network.
 160  * This is a blocking network operation.
 161  *
 162  * @param fd stream socket through which to establish the secure communication
 163  * layer.
 164  * @param psz_hostname Server Name Indication to pass to the server, or NULL.
 165  *
 166  * @return NULL on error.
 167  **/
 168 vlc_tls_t *
 169 vlc_tls_ClientCreate (vlc_object_t *obj, int fd, const char *hostname)
 170 {
 171     vlc_tls_t *cl = vlc_custom_create (obj, sizeof (*cl), "tls client");
 172     if (unlikely(cl == NULL))
 173         return NULL;
 174
 175     cl->u.module = vlc_module_load (cl, "tls client", NULL, false,
 176                                     tls_client_start, cl, fd, hostname);
 177     if (cl->u.module == NULL)
 178     {
 179         msg_Err (cl, "TLS client plugin not available");
 180         vlc_object_release (cl);
 181         return NULL;
 182     }
 183
 184     /* TODO: do this directly in the TLS plugin */
 185     int val;
 186     do
 187         val = cl->handshake (cl);
 188     while (val > 0);
 189
 190     if (val != 0)
 191     {
 192         msg_Err (cl, "TLS client session handshake error");
 193         vlc_module_unload (cl->u.module, tls_client_stop, cl);
 194         vlc_object_release (cl);
 195         return NULL;
 196     }
 197     msg_Dbg (cl, "TLS client session initialized");
 198     return cl;
 199 }
 200
 201
 202 /**
 203  * Releases data allocated with vlc_tls_ClientCreate().
 204  * It is your job to close the underlying socket.
 205  */
 206 void vlc_tls_ClientDelete (vlc_tls_t *cl)
 207 {
 208     if (cl == NULL)
 209         return;
 210
 211     vlc_module_unload (cl->u.module, tls_client_stop, cl);
 212     vlc_object_release (cl);
 213 }