/* * ircd-ratbox: A slightly useful ircd. * m_challenge.c: Allows an IRC Operator to securely authenticate. * * Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center * Copyright (C) 1996-2002 Hybrid Development Team * Copyright (C) 2002-2005 ircd-ratbox development team * * 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 2 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, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 * USA * * $Id: m_challenge.c 3161 2007-01-25 07:23:01Z nenolod $ */ #include "stdinc.h" #ifdef HAVE_LIBCRYPTO #include #include #include #include #include #include #include #endif #include "client.h" #include "ircd.h" #include "modules.h" #include "numeric.h" #include "send.h" #include "s_conf.h" #include "msg.h" #include "parse.h" #include "irc_string.h" #include "logger.h" #include "s_user.h" #include "cache.h" #include "s_newconf.h" #define CHALLENGE_WIDTH BUFSIZE - (NICKLEN + HOSTLEN + 12) #define CHALLENGE_EXPIRES 180 /* 180 seconds should be more than long enough */ #define CHALLENGE_SECRET_LENGTH 128 /* how long our challenge secret should be */ #ifndef HAVE_LIBCRYPTO /* Maybe this should be an error or something?-davidt */ /* now it is -larne */ static int challenge_load(void) { #ifndef STATIC_MODULES sendto_realops_snomask(SNO_GENERAL, L_ALL, "Challenge module not loaded because OpenSSL is not available."); ilog(L_MAIN, "Challenge module not loaded because OpenSSL is not available."); return -1; #else return 0; #endif } DECLARE_MODULE_AV1(challenge, challenge_load, NULL, NULL, NULL, NULL, "$Revision: 3161 $"); #else static int m_challenge(struct Client *, struct Client *, int, const char **); /* We have openssl support, so include /CHALLENGE */ struct Message challenge_msgtab = { "CHALLENGE", 0, 0, 0, MFLG_SLOW, {mg_unreg, {m_challenge, 2}, mg_ignore, mg_ignore, mg_ignore, {m_challenge, 2}} }; mapi_clist_av1 challenge_clist[] = { &challenge_msgtab, NULL }; DECLARE_MODULE_AV1(challenge, NULL, NULL, challenge_clist, NULL, NULL, "$Revision: 3161 $"); static int generate_challenge(char **r_challenge, char **r_response, RSA * key); static void cleanup_challenge(struct Client *target_p) { if(target_p->localClient == NULL) return; rb_free(target_p->localClient->challenge); rb_free(target_p->localClient->opername); target_p->localClient->challenge = NULL; target_p->localClient->opername = NULL; target_p->localClient->chal_time = 0; } /* * m_challenge - generate RSA challenge for wouldbe oper * parv[0] = sender prefix * parv[1] = operator to challenge for, or +response * */ static int m_challenge(struct Client *client_p, struct Client *source_p, int parc, const char *parv[]) { struct oper_conf *oper_p; char *challenge = NULL; /* to placate gcc */ char chal_line[CHALLENGE_WIDTH]; unsigned char *b_response; size_t cnt; int len = 0; /* if theyre an oper, reprint oper motd and ignore */ if(IsOper(source_p)) { sendto_one(source_p, form_str(RPL_YOUREOPER), me.name, source_p->name); send_oper_motd(source_p); return 0; } if(*parv[1] == '+') { /* Ignore it if we aren't expecting this... -A1kmm */ if(!source_p->localClient->challenge) return 0; if((rb_current_time() - source_p->localClient->chal_time) > CHALLENGE_EXPIRES) { sendto_one(source_p, form_str(ERR_PASSWDMISMATCH), me.name, source_p->name); ilog(L_FOPER, "EXPIRED CHALLENGE (%s) by (%s!%s@%s) (%s)", source_p->localClient->opername, source_p->name, source_p->username, source_p->host, source_p->sockhost); if(ConfigFileEntry.failed_oper_notice) sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "Expired CHALLENGE attempt by %s (%s@%s)", source_p->name, source_p->username, source_p->host); cleanup_challenge(source_p); return 0; } b_response = rb_base64_decode((const unsigned char *)++parv[1], strlen(parv[1]), &len); if(len != SHA_DIGEST_LENGTH || memcmp(source_p->localClient->challenge, b_response, SHA_DIGEST_LENGTH)) { sendto_one(source_p, form_str(ERR_PASSWDMISMATCH), me.name, source_p->name); ilog(L_FOPER, "FAILED CHALLENGE (%s) by (%s!%s@%s) (%s)", source_p->localClient->opername, source_p->name, source_p->username, source_p->host, source_p->sockhost); if(ConfigFileEntry.failed_oper_notice) sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "Failed CHALLENGE attempt by %s (%s@%s)", source_p->name, source_p->username, source_p->host); rb_free(b_response); cleanup_challenge(source_p); return 0; } rb_free(b_response); oper_p = find_oper_conf(source_p->username, source_p->orighost, source_p->sockhost, source_p->localClient->opername); if(oper_p == NULL) { sendto_one(source_p, form_str(ERR_NOOPERHOST), me.name, source_p->name); ilog(L_FOPER, "FAILED OPER (%s) by (%s!%s@%s) (%s)", source_p->localClient->opername, source_p->name, source_p->username, source_p->host, source_p->sockhost); if(ConfigFileEntry.failed_oper_notice) sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "Failed CHALLENGE attempt - host mismatch by %s (%s@%s)", source_p->name, source_p->username, source_p->host); return 0; } cleanup_challenge(source_p); oper_up(source_p, oper_p); ilog(L_OPERED, "OPER %s by %s!%s@%s (%s)", source_p->localClient->opername, source_p->name, source_p->username, source_p->host, source_p->sockhost); return 0; } cleanup_challenge(source_p); oper_p = find_oper_conf(source_p->username, source_p->orighost, source_p->sockhost, parv[1]); if(oper_p == NULL) { sendto_one(source_p, form_str(ERR_NOOPERHOST), me.name, source_p->name); ilog(L_FOPER, "FAILED OPER (%s) by (%s!%s@%s) (%s)", parv[1], source_p->name, source_p->username, source_p->host, source_p->sockhost); if(ConfigFileEntry.failed_oper_notice) sendto_realops_snomask(SNO_GENERAL, L_NETWIDE, "Failed CHALLENGE attempt - host mismatch by %s (%s@%s)", source_p->name, source_p->username, source_p->host); return 0; } if(!oper_p->rsa_pubkey) { sendto_one_notice(source_p, ":I'm sorry, PK authentication is not enabled for your oper{} block."); return 0; } if(!generate_challenge(&challenge, &(source_p->localClient->challenge), oper_p->rsa_pubkey)) { char *chal = challenge; source_p->localClient->chal_time = rb_current_time(); for(;;) { cnt = strlcpy(chal_line, chal, CHALLENGE_WIDTH); sendto_one(source_p, form_str(RPL_RSACHALLENGE2), me.name, source_p->name, chal_line); if(cnt > CHALLENGE_WIDTH) chal += CHALLENGE_WIDTH - 1; else break; } sendto_one(source_p, form_str(RPL_ENDOFRSACHALLENGE2), me.name, source_p->name); rb_free(challenge); source_p->localClient->opername = rb_strdup(oper_p->name); } else sendto_one_notice(source_p, ":Failed to generate challenge."); return 0; } static int generate_challenge(char **r_challenge, char **r_response, RSA * rsa) { SHA_CTX ctx; unsigned char secret[CHALLENGE_SECRET_LENGTH], *tmp; unsigned long length; unsigned long e = 0; unsigned long cnt = 0; int ret; if(!rsa) return -1; if(rb_get_random(secret, CHALLENGE_SECRET_LENGTH)) { SHA1_Init(&ctx); SHA1_Update(&ctx, (uint8_t *)secret, CHALLENGE_SECRET_LENGTH); *r_response = malloc(SHA_DIGEST_LENGTH); SHA1_Final((uint8_t *)*r_response, &ctx); length = RSA_size(rsa); tmp = rb_malloc(length); ret = RSA_public_encrypt(CHALLENGE_SECRET_LENGTH, secret, tmp, rsa, RSA_PKCS1_OAEP_PADDING); if(ret >= 0) { *r_challenge = (char *)rb_base64_encode(tmp, ret); rb_free(tmp); return 0; } rb_free(tmp); rb_free(*r_response); *r_response = NULL; } ERR_load_crypto_strings(); while ((cnt < 100) && (e = ERR_get_error())) { ilog(L_MAIN, "SSL error: %s", ERR_error_string(e, 0)); cnt++; } return (-1); } #endif /* HAVE_LIBCRYPTO */