Add mechanism DH-BLOWFISH for SASL authentication with IRC server

src/plugins/irc/CMakeLists.txt

@@ -34,6 +34,7 @@ irc-msgbuffer.c irc-msgbuffer.h
 irc-nick.c irc-nick.h
 irc-protocol.c irc-protocol.h
 irc-raw.c irc-raw.h
+irc-sasl.c irc-sasl.h
 irc-server.c irc-server.h
 irc-upgrade.c irc-upgrade.h)
 SET_TARGET_PROPERTIES(irc PROPERTIES PREFIX "")
@@ -41,11 +42,17 @@ SET_TARGET_PROPERTIES(irc PROPERTIES PREFIX "")
 CHECK_INCLUDE_FILES("regex.h" HAVE_REGEX_H)
 CHECK_FUNCTION_EXISTS(regexec HAVE_REGEXEC)
 
+SET (LINK_LIBS)
+
 IF(GNUTLS_FOUND)
   INCLUDE_DIRECTORIES(${GNUTLS_INCLUDE_PATH})
-  TARGET_LINK_LIBRARIES(irc ${GNUTLS_LIBRARY})
-ELSE(GNUTLS_FOUND)
-  TARGET_LINK_LIBRARIES(irc)
+  LIST(APPEND LINK_LIBS ${GNUTLS_LIBRARY})
 ENDIF(GNUTLS_FOUND)
 
+IF(GCRYPT_FOUND)
+  LIST(APPEND LINK_LIBS gcrypt)
+ENDIF(GCRYPT_FOUND)
+
+TARGET_LINK_LIBRARIES(irc ${LINK_LIBS})
+
 INSTALL(TARGETS irc LIBRARY DESTINATION ${LIBDIR}/plugins)

src/plugins/irc/Makefile.am

@@ -14,7 +14,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 
-INCLUDES = -DLOCALEDIR=\"$(datadir)/locale\" $(GNUTLS_CFLAGS)
+INCLUDES = -DLOCALEDIR=\"$(datadir)/locale\" $(GCRYPT_CFLAGS) $(GNUTLS_CFLAGS)
 
 libdir = ${weechat_libdir}/plugins
 
@@ -58,12 +58,14 @@ irc_la_SOURCES = irc.c \
                  irc-protocol.h \
                  irc-raw.c \
                  irc-raw.h \
+                 irc-sasl.c \
+                 irc-sasl.h \
                  irc-server.c \
                  irc-server.h \
                  irc-upgrade.c \
                  irc-upgrade.h
 
 irc_la_LDFLAGS = -module
-irc_la_LIBADD  = $(IRC_LFLAGS) $(GNUTLS_LFLAGS)
+irc_la_LIBADD  = $(IRC_LFLAGS) $(GCRYPT_LFLAGS) $(GNUTLS_LFLAGS)
 
 EXTRA_DIST = CMakeLists.txt

src/plugins/irc/irc-config.c

@@ -969,7 +969,7 @@ irc_config_server_new_option (struct t_config_file *config_file,
                 config_file, section,
                 option_name, "integer",
                 N_("mechanism for SASL authentication"),
-                "plain" /*"plain|dh-blowfish"*/, 0, 0,
+                "plain|dh-blowfish", 0, 0,
                 default_value, value,
                 null_value_allowed,
                 NULL, NULL,
@@ -1000,6 +1000,19 @@ irc_config_server_new_option (struct t_config_file *config_file,
                 callback_change, callback_change_data,
                 NULL, NULL);
             break;
+        case IRC_SERVER_OPTION_SASL_TIMEOUT:
+            new_option = weechat_config_new_option (
+                config_file, section,
+                option_name, "integer",
+                N_("timeout (in seconds) before giving up SASL "
+                   "authentication"),
+                NULL, 1, 3600,
+                default_value, value,
+                null_value_allowed,
+                NULL, NULL,
+                callback_change, callback_change_data,
+                NULL, NULL);
+            break;
         case IRC_SERVER_OPTION_AUTOCONNECT:
             new_option = weechat_config_new_option (
                 config_file, section,

src/plugins/irc/irc-display.c

@@ -29,8 +29,9 @@
 #include "irc-channel.h"
 #include "irc-command.h"
 #include "irc-config.h"
-#include "irc-server.h"
 #include "irc-nick.h"
+#include "irc-server.h"
+#include "irc-sasl.h"
 
 
 /*

src/plugins/irc/irc-protocol.c

@@ -44,6 +44,7 @@
 #include "irc-mode.h"
 #include "irc-msgbuffer.h"
 #include "irc-nick.h"
+#include "irc-sasl.h"
 #include "irc-server.h"
 
 
@@ -224,8 +225,7 @@ irc_protocol_cmd_authenticate (struct t_irc_server *server, const char *command,
                                int argc, char **argv, char **argv_eol)
 {
     const char *sasl_username, *sasl_password;
-    char *string, *string_base64;
-    int length_username, length;
+    char *answer;
     
     /* AUTHENTICATE message looks like:
        AUTHENTICATE +
@@ -236,7 +236,7 @@ irc_protocol_cmd_authenticate (struct t_irc_server *server, const char *command,
     
     /* make C compiler happy */
     (void) command;
-    (void) argv_eol;
+    (void) argv;
     
     sasl_username = IRC_SERVER_OPTION_STRING(server,
                                              IRC_SERVER_OPTION_SASL_USERNAME);
@@ -245,33 +245,33 @@ irc_protocol_cmd_authenticate (struct t_irc_server *server, const char *command,
     if (sasl_username && sasl_username[0]
         && sasl_password && sasl_password[0])
     {
-        length_username = strlen (sasl_username);
-        length = ((length_username + 1) * 2) + strlen (sasl_password) + 1;
-        string = malloc (length);
-        if (string)
+        switch (IRC_SERVER_OPTION_INTEGER(server,
+                                          IRC_SERVER_OPTION_SASL_MECHANISM))
         {
-            snprintf (string, length, "%s|%s|%s",
-                      sasl_username, sasl_username, sasl_password);
-            string[length_username] = '\0';
-            string[(length_username * 2) + 1] = '\0';
-            
-            if (strcmp (argv[1], "+") == 0)
-            {
-                /* mechanism PLAIN */
-                string_base64 = malloc (length * 2);
-                if (string_base64)
-                {
-                    weechat_string_encode_base64 (string, length - 1, string_base64);
-                    irc_server_sendf (server, 0, "AUTHENTICATE %s", string_base64);
-                    free (string_base64);
-                }
-            }
-            else
-            {
-                /* TODO: other mechanisms */
-            }
-            
-            free (string);
+            case IRC_SASL_MECHANISM_DH_BLOWFISH:
+                answer = irc_sasl_mechanism_dh_blowfish (argv_eol[1],
+                                                         sasl_username,
+                                                         sasl_password);
+                break;
+            case IRC_SASL_MECHANISM_PLAIN:
+            default:
+                answer = irc_sasl_mechanism_plain (sasl_username,
+                                                   sasl_password);
+                break;
+        }
+        if (answer)
+        {
+            irc_server_sendf (server, 0, "AUTHENTICATE %s", answer);
+            free (answer);
+        }
+        else
+        {
+            weechat_printf (server->buffer,
+                            _("%s%s: error building answer for "
+                              "SASL authentication, using mechanism \"%s\""),
+                            weechat_prefix ("error"), IRC_PLUGIN_NAME,
+                            irc_sasl_mechanism_string[IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_SASL_MECHANISM)]);
+            irc_server_sendf (server, 0, "CAP END");
         }
     }
     
@@ -287,11 +287,12 @@ irc_protocol_cmd_cap (struct t_irc_server *server, const char *command,
                       int argc, char **argv, char **argv_eol)
 {
     char *ptr_caps, **items;
-    int num_items, sasl, i;
+    int num_items, sasl, i, timeout;
     
     /* CAP message looks like:
        :server CAP * LS :identify-msg multi-prefix sasl
        :server CAP * ACK :sasl
+       :server CAP * NAK :sasl
     */
     
     IRC_PROTOCOL_MIN_ARGS(4);
@@ -348,14 +349,27 @@ irc_protocol_cmd_cap (struct t_irc_server *server, const char *command,
             ptr_caps = (argv_eol[4][0] == ':') ? argv_eol[4] + 1 : argv_eol[4];
             weechat_printf (server->buffer,
                             _("%s%s: client capability, enabled: %s"),
-                            weechat_prefix ("network"),
-                            IRC_PLUGIN_NAME,
+                            weechat_prefix ("network"), IRC_PLUGIN_NAME,
                             ptr_caps);
             if (strcmp (ptr_caps, "sasl") == 0)
             {
                 switch (IRC_SERVER_OPTION_INTEGER(server,
                                                   IRC_SERVER_OPTION_SASL_MECHANISM))
                 {
+                    case IRC_SASL_MECHANISM_DH_BLOWFISH:
+#ifdef HAVE_GCRYPT
+                        irc_server_sendf (server, 0, "AUTHENTICATE DH-BLOWFISH");
+#else
+                        weechat_printf (server->buffer,
+                                        _("%s%s: cannot authenticate with SASL "
+                                          "and mechanism DH-BLOWFISH because "
+                                          "WeeChat was not built with "
+                                          "libgcrypt support"),
+                                        weechat_prefix ("error"),
+                                        IRC_PLUGIN_NAME);
+                        irc_server_sendf (server, 0, "CAP END");
+#endif
+                        break;
                     case IRC_SASL_MECHANISM_PLAIN:
                     default:
                         irc_server_sendf (server, 0, "AUTHENTICATE PLAIN");
@@ -363,12 +377,28 @@ irc_protocol_cmd_cap (struct t_irc_server *server, const char *command,
                 }
                 if (server->hook_timer_sasl)
                     weechat_unhook (server->hook_timer_sasl);
-                server->hook_timer_sasl = weechat_hook_timer (5 * 1000, 0, 1,
+                timeout = IRC_SERVER_OPTION_INTEGER(server,
+                                                    IRC_SERVER_OPTION_SASL_TIMEOUT);
+                server->hook_timer_sasl = weechat_hook_timer (timeout * 1000,
+                                                              0, 1,
                                                               &irc_server_timer_sasl_cb,
                                                               server);
             }
         }
     }
+    else if (strcmp (argv[3], "NAK") == 0)
+    {
+        if (argc > 4)
+        {
+            ptr_caps = (argv_eol[4][0] == ':') ? argv_eol[4] + 1 : argv_eol[4];
+            weechat_printf (server->buffer,
+                            _("%s%s: client capability, refused: %s"),
+                            weechat_prefix ("error"), IRC_PLUGIN_NAME,
+                            ptr_caps);
+            if (!server->is_connected)
+                irc_server_sendf (server, 0, "CAP END");
+        }
+    }
     
     return WEECHAT_RC_OK;
 }

src/plugins/irc/irc-sasl.c

@@ -0,0 +1,236 @@
+/*
+ * Copyright (c) 2003-2010 by FlashCode <flashcode@flashtux.org>
+ * See README for License detail, AUTHORS for developers list.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/* irc-sasl.c: SASL authentication with IRC server */
+
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <arpa/inet.h>
+
+#ifdef HAVE_GCRYPT
+#include <gcrypt.h>
+#endif
+
+#include "../weechat-plugin.h"
+#include "irc.h"
+#include "irc-sasl.h"
+
+
+char *irc_sasl_mechanism_string[IRC_NUM_SASL_MECHANISMS] =
+{ "plain", "dh-blowfish" };
+
+
+/*
+ * irc_sasl_mechanism_plain: build answer for SASL authentication, using
+ *                           mechanism "PLAIN"
+ *                           Note: result must be freed after use
+ */
+
+char *
+irc_sasl_mechanism_plain (const char *sasl_username, const char *sasl_password)
+{
+    char *string, *answer_base64;
+    int length_username, length;
+    
+    length_username = strlen (sasl_username);
+    length = ((length_username + 1) * 2) + strlen (sasl_password) + 1;
+    string = malloc (length);
+    if (string)
+    {
+        snprintf (string, length, "%s|%s|%s",
+                  sasl_username, sasl_username, sasl_password);
+        string[length_username] = '\0';
+        string[(length_username * 2) + 1] = '\0';
+        
+        answer_base64 = malloc (length * 2);
+        if (answer_base64)
+            weechat_string_encode_base64 (string, length - 1, answer_base64);
+        
+        free (string);
+    }
+    
+    return answer_base64;
+}
+
+/*
+ * irc_sasl_mechanism_dh_blowfish: build answer for SASL authentication, using
+ *                                 mechanism "DH-BLOWFISH"
+ *                                 Note: result must be freed after use
+ *
+ *                                 data_base64 is a concatenation of 3 strings,
+ *                                 each string is composed of 2 bytes (length
+ *                                 of string), followed by content of string:
+ *                                   1. a prime number
+ *                                   2. a generator number
+ *                                   3. server-generated public key
+ */
+
+char *
+irc_sasl_mechanism_dh_blowfish (const char *data_base64,
+                                const char *sasl_username,
+                                const char *sasl_password)
+{
+#ifdef HAVE_GCRYPT
+    char *data, *answer, *ptr_answer, *answer_base64;
+    unsigned char *ptr_data, *secret_bin, *public_bin;
+    unsigned char *password_clear, *password_crypted;
+    int length_data, size, num_bits_prime_number, length_key;
+    int length_username, length_password, length_answer;
+    size_t num_written;
+    gcry_mpi_t data_prime_number, data_generator_number, data_server_pub_key;
+    gcry_mpi_t pub_key, priv_key, secret_mpi;
+    gcry_cipher_hd_t gcrypt_handle;
+    
+    data = NULL;
+    secret_bin = NULL;
+    public_bin = NULL;
+    password_clear = NULL;
+    password_crypted = NULL;
+    answer = NULL;
+    answer_base64 = NULL;
+    
+    /* decode data */
+    data = malloc (strlen (data_base64) + 1);
+    length_data = weechat_string_decode_base64 (data_base64, data);
+    ptr_data = (unsigned char *)data;
+    
+    /* extract prime number */
+    size = ntohs ((((unsigned int)ptr_data[1]) << 8) | ptr_data[0]);
+    ptr_data += 2;
+    length_data -= 2;
+    if (size > length_data)
+        goto end;
+    data_prime_number = gcry_mpi_new (size * 8);
+    gcry_mpi_scan (&data_prime_number, GCRYMPI_FMT_USG, ptr_data, size, NULL);
+    num_bits_prime_number = gcry_mpi_get_nbits (data_prime_number);
+    ptr_data += size;
+    length_data -= size;
+    
+    /* extract generator number */
+    size = ntohs ((((unsigned int)ptr_data[1]) << 8) | ptr_data[0]);
+    ptr_data += 2;
+    length_data -= 2;
+    if (size > length_data)
+        goto end;
+    data_generator_number = gcry_mpi_new (size * 8);
+    gcry_mpi_scan (&data_generator_number, GCRYMPI_FMT_USG, ptr_data, size, NULL);
+    ptr_data += size;
+    length_data -= size;
+    
+    /* extract server-generated public key */
+    size = ntohs ((((unsigned int)ptr_data[1]) << 8) | ptr_data[0]);
+    ptr_data += 2;
+    length_data -= 2;
+    if (size > length_data)
+        goto end;
+    data_server_pub_key = gcry_mpi_new (size * 8);
+    gcry_mpi_scan (&data_server_pub_key, GCRYMPI_FMT_USG, ptr_data, size, NULL);
+    ptr_data += size;
+    length_data -= size;
+    
+    /* generate keys */
+    pub_key = gcry_mpi_new (num_bits_prime_number);
+    priv_key = gcry_mpi_new (num_bits_prime_number);
+    gcry_mpi_randomize (priv_key, num_bits_prime_number, GCRY_STRONG_RANDOM);
+    /* pub_key = (g ^ priv_key) % p */
+    gcry_mpi_powm (pub_key, data_generator_number, priv_key, data_prime_number);
+    
+    /* compute secret_bin */
+    length_key = num_bits_prime_number / 8;
+    secret_bin = malloc (length_key);
+    secret_mpi = gcry_mpi_new (num_bits_prime_number);
+    /* secret_mpi = (y ^ priv_key) % p */
+    gcry_mpi_powm (secret_mpi, data_server_pub_key, priv_key, data_prime_number);
+    gcry_mpi_print (GCRYMPI_FMT_USG, secret_bin, length_key,
+                    &num_written, secret_mpi);
+    
+    /* create public_bin */
+    public_bin = malloc (length_key);
+    gcry_mpi_print (GCRYMPI_FMT_USG, public_bin, length_key,
+                    &num_written, pub_key);
+    
+    /* create password buffers (clear and crypted) */
+    length_password = strlen (sasl_password) +
+        ((8 - (strlen (sasl_password) % 8)) % 8);
+    password_clear = malloc (length_password);
+    password_crypted = malloc (length_password);
+    memset (password_clear, 0, length_password);
+    memset (password_crypted, 0, length_password);
+    memcpy (password_clear, sasl_password, strlen (sasl_password));
+    
+    /* crypt password using blowfish */
+    if (gcry_cipher_open (&gcrypt_handle, GCRY_CIPHER_BLOWFISH,
+                          GCRY_CIPHER_MODE_ECB, 0) != 0)
+        goto end;
+    if (gcry_cipher_setkey (gcrypt_handle, secret_bin, length_key) != 0)
+        goto end;
+    if (gcry_cipher_encrypt (gcrypt_handle,
+                             password_crypted, length_password,
+                             password_clear, length_password) != 0)
+        goto end;
+    
+    /* build answer for server, it is concatenation of:
+         1. key length (2 bytes)
+         2. public key ('length_key' bytes)
+         3. sasl_username ('length_username'+1 bytes)
+         4. encrypted password ('length_password' bytes)
+    */
+    length_username = strlen (sasl_username);
+    length_answer = 2 + length_key + length_username + 1 + length_password;
+    answer = malloc (length_answer);
+    ptr_answer = answer;
+    *((unsigned int *)ptr_answer) = htons(length_key);
+    ptr_answer += 2;
+    memcpy (ptr_answer, public_bin, length_key);
+    ptr_answer += length_key;
+    memcpy (ptr_answer, sasl_username, length_username + 1);
+    ptr_answer += length_username + 1;
+    memcpy (ptr_answer, password_crypted, length_password);
+    ptr_answer += length_password;
+    
+    /* encode answer to base64 */
+    answer_base64 = malloc (length_answer * 2);
+    if (answer_base64)
+        weechat_string_encode_base64 (answer, length_answer, answer_base64);
+    
+end:
+    if (data)
+        free (data);
+    if (secret_bin)
+        free (secret_bin);
+    if (public_bin)
+        free (public_bin);
+    if (password_clear)
+        free (password_clear);
+    if (password_crypted)
+        free (password_crypted);
+    if (answer)
+        free (answer);
+    
+    return answer_base64;
+#else
+    /* make C compiler happy */
+    (void) data_base64;
+    (void) sasl_username;
+    (void) sasl_password;
+    
+    return NULL;
+#endif
+}

src/plugins/irc/irc-sasl.h

@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2003-2010 by FlashCode <flashcode@flashtux.org>
+ * See README for License detail, AUTHORS for developers list.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+#ifndef __WEECHAT_IRC_SASL_H
+#define __WEECHAT_IRC_SASL_H 1
+
+/* SASL authentication mechanisms */
+
+enum t_irc_sasl_mechanism
+{
+    IRC_SASL_MECHANISM_PLAIN = 0,
+    IRC_SASL_MECHANISM_DH_BLOWFISH,
+    /* number of SASL mechanisms */
+    IRC_NUM_SASL_MECHANISMS,
+};
+
+extern char *irc_sasl_mechanism_string[];
+
+extern char *irc_sasl_mechanism_plain (const char *sasl_username,
+                                       const char *sasl_password);
+extern char *irc_sasl_mechanism_dh_blowfish (const char *data_base64,
+                                             const char *sasl_username,
+                                             const char *sasl_password);
+
+#endif /* irc-sasl.h */

src/plugins/irc/irc-server.c

@@ -49,6 +49,7 @@
 #include "irc-nick.h"
 #include "irc-protocol.h"
 #include "irc-raw.h"
+#include "irc-sasl.h"
 
 
 struct t_irc_server *irc_servers = NULL;
@@ -60,7 +61,7 @@ struct t_irc_message *irc_msgq_last_msg = NULL;
 char *irc_server_option_string[IRC_SERVER_NUM_OPTIONS] =
 { "addresses", "proxy", "ipv6",
   "ssl", "ssl_cert", "ssl_dhkey_size", "ssl_verify",
-  "password", "sasl_mechanism", "sasl_username", "sasl_password",
+  "password", "sasl_mechanism", "sasl_username", "sasl_password", "sasl_timeout",
   "autoconnect", "autoreconnect", "autoreconnect_delay",
   "nicks", "username", "realname", "local_hostname",
   "command", "command_delay", "autojoin", "autorejoin", "autorejoin_delay",
@@ -69,15 +70,12 @@ char *irc_server_option_string[IRC_SERVER_NUM_OPTIONS] =
 char *irc_server_option_default[IRC_SERVER_NUM_OPTIONS] =
 { "", "", "off",
   "off", "", "2048", "on",
-  "", "plain", "", "",
+  "", "plain", "", "", "15",
   "off", "on", "30",
   "", "", "", "",
   "", "0", "", "off", "30",
 };
 
-char *irc_sasl_mechanism_string[IRC_NUM_SASL_MECHANISMS] =
-{ "plain", /*"dh-blowfish"*/ };
-
 
 void irc_server_reconnect (struct t_irc_server *server);
 void irc_server_check_away ();

src/plugins/irc/irc-server.h

@@ -44,6 +44,7 @@ enum t_irc_server_option
     IRC_SERVER_OPTION_SASL_MECHANISM,/* mechanism for SASL authentication    */
     IRC_SERVER_OPTION_SASL_USERNAME, /* username for SASL authentication     */
     IRC_SERVER_OPTION_SASL_PASSWORD, /* password for SASL authentication     */
+    IRC_SERVER_OPTION_SASL_TIMEOUT,  /* timeout for SASL authentication      */
     IRC_SERVER_OPTION_AUTOCONNECT,   /* autoconnect to server at startup     */
     IRC_SERVER_OPTION_AUTORECONNECT, /* autoreconnect when disconnected      */
     IRC_SERVER_OPTION_AUTORECONNECT_DELAY, /* delay before trying again reco */
@@ -90,16 +91,6 @@ enum t_irc_server_option
 #define IRC_SERVER_OUTQUEUE_PRIO_LOW  2
 #define IRC_SERVER_NUM_OUTQUEUES_PRIO 2
 
-/* SASL authentication mechanisms */
-
-enum t_irc_sasl_mechanism
-{
-    IRC_SASL_MECHANISM_PLAIN = 0,
-    /* TODO: IRC_SASL_MECHANISM_DH_BLOWFISH, */
-    /* number of SASL mechanisms */
-    IRC_NUM_SASL_MECHANISMS,
-};
-
 /* output queue of messages to server (for sending slowly to server) */
 
 struct t_irc_outqueue
@@ -185,7 +176,6 @@ extern const int gnutls_prot_prio[];
 extern struct t_irc_message *irc_recv_msgq, *irc_msgq_last_msg;
 extern char *irc_server_option_string[];
 extern char *irc_server_option_default[];
-extern char *irc_sasl_mechanism_string[];
 
 extern int irc_server_valid (struct t_irc_server *server);
 extern int irc_server_search_option (const char *option_name);