+/*
+ * IRC - Internet Relay Chat, ircd/ircd_crypt.c
+ * Copyright (C) 2002 hikari
+ *
+ * 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 1, 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+/**
+ * @file
+ * @brief Core password encryption routines.
+ * @version $Id$
+ *
+ * This is a new look crypto API for ircu, it can handle different
+ * password formats by the grace of magic tokens at the beginning of the
+ * password e.g. $SMD5 for Salted MD5, $CRYPT for native crypt(), etc.
+ *
+ * Currently crypt routines are implemented for: the native crypt()
+ * function, Salted MD5 and a plain text mechanism which should only
+ * be used for testing. I intend to add Blowfish, 3DES and possibly
+ * SHA1 support as well at some point, but I'll need to check the
+ * possible problems that'll cause with stupid crypto laws.
+ *
+ * It's also designed to be "ready" for the modularisation of ircu, so
+ * someone get round to doing it, because I'm not doing it ;)
+ *
+ * The plan for Stage B is to semi-modularise the authentication
+ * mechanism to allow authentication against some other sources than
+ * the conf file (whatever takes someones fancy, kerberos, ldap, sql, etc).
+ *
+ * -- blessed be, hikari.
+ */
+
+#include "config.h"
+#include "ircd_crypt.h"
+#include "ircd_alloc.h"
+#include "ircd_features.h"
+#include "ircd_log.h"
+#include "ircd_string.h"
+#include "s_debug.h"
+
+/* while we're not modular, we need their init functions */
+#include "ircd_crypt_native.h"
+#include "ircd_crypt_plain.h"
+#include "ircd_crypt_smd5.h"
+
+/* #include <assert.h> -- Now using assert in ircd_log.h */
+#include <unistd.h>
+#include <string.h>
+
+/* evil global */
+crypt_mechs_t* crypt_mechs_root;
+
+/** Add a crypt mechanism to the list
+ * @param mechanism Pointer to the mechanism details struct
+ * @return 0 on success, anything else on fail.
+ *
+ * This routine registers a new crypt mechanism in the loaded mechanisms list,
+ * making it availabe for comparing passwords.
+*/
+int ircd_crypt_register_mech(crypt_mech_t* mechanism)
+{
+crypt_mechs_t* crypt_mech;
+
+ Debug((DEBUG_INFO, "ircd_crypt_register_mech: registering mechanism: %s", mechanism->shortname));
+
+ /* try to allocate some memory for the new mechanism */
+ if ((crypt_mech = (crypt_mechs_t*)MyMalloc(sizeof(crypt_mechs_t))) == NULL)
+ {
+ /* aww poot, we couldn't get any memory, scream a little then back out */
+ Debug((DEBUG_MALLOC, "ircd_crypt_register_mech: could not allocate memory for %s", mechanism->shortname));
+ return -1;
+ }
+
+ /* ok, we have memory, initialise it */
+ memset(crypt_mech, 0, sizeof(crypt_mechs_t));
+
+ /* assign the data */
+ crypt_mech->mech = mechanism;
+ crypt_mech->next = crypt_mech->prev = NULL;
+
+ /* first of all, is there anything there already? */
+ if(crypt_mechs_root->next == NULL)
+ {
+ /* nope, just add ourself */
+ crypt_mechs_root->next = crypt_mechs_root->prev = crypt_mech;
+ } else {
+ /* nice and simple, put ourself at the end */
+ crypt_mech->prev = crypt_mechs_root->prev;
+ crypt_mech->next = NULL;
+ crypt_mechs_root->prev = crypt_mech->prev->next = crypt_mech;
+ }
+
+ /* we're done */
+ Debug((DEBUG_INFO, "ircd_crypt_register_mech: registered mechanism: %s, crypt_function is at 0x%X.", crypt_mech->mech->shortname, &crypt_mech->mech->crypt_function));
+ Debug((DEBUG_INFO, "ircd_crypt_register_mech: %s: %s", crypt_mech->mech->shortname, crypt_mech->mech->description));
+ return 0;
+}
+
+/** Remove a crypt mechanism from the list
+ * @param mechanism Pointer to the mechanism we want to remove
+ * @return 0 on success, anything else on fail.
+*/
+int ircd_crypt_unregister_mech(crypt_mech_t* mechanism)
+{
+
+return 0;
+}
+
+/** Wrapper for generating a hashed password passed on the supplied password
+ * @param key Pointer to the password we want crypted
+ * @param salt Pointer to the password we're comparing to (for the salt)
+ * @return Pointer to the generated password (must be MyFree()'d).
+ *
+ * This is a wrapper function which attempts to establish the password
+ * format and funnel it off to the correct mechanism handler function. The
+ * returned password is compared in the oper_password_match() routine.
+*/
+char* ircd_crypt(const char* key, const char* salt)
+{
+char *hashed_pass = NULL;
+const char *temp_hashed_pass, *mysalt;
+crypt_mechs_t* crypt_mech;
+
+ assert(NULL != key);
+ assert(NULL != salt);
+
+ Debug((DEBUG_DEBUG, "ircd_crypt: key is %s", key));
+ Debug((DEBUG_DEBUG, "ircd_crypt: salt is %s", salt));
+
+ crypt_mech = crypt_mechs_root->next;
+
+ /* by examining the first n characters of a password string we
+ * can discover what kind of password it is. hopefully. */
+ for (;crypt_mech;)
+ {
+ if (strlen(salt) < crypt_mech->mech->crypt_token_size)
+ {
+ /* try the next mechanism instead */
+ Debug((DEBUG_DEBUG, "ircd_crypt: salt is too short, will try next mech at 0x%X", crypt_mech->next));
+ crypt_mech = crypt_mech->next;
+ continue;
+ }
+
+ Debug((DEBUG_DEBUG, "ircd_crypt: comparing %s with %s",
+ salt, crypt_mech->mech->crypt_token));
+
+ if(0 == ircd_strncmp(crypt_mech->mech->crypt_token, salt, crypt_mech->mech->crypt_token_size))
+ {
+ Debug((DEBUG_DEBUG, "ircd_crypt: type is %s",
+ crypt_mech->mech->shortname));
+
+ /* before we send this all off to the crypt_function, we need to remove
+ the tag from it */
+
+ /* make sure we won't end up with a password comprised entirely of
+ a single \0 */
+ if(strlen(salt) < crypt_mech->mech->crypt_token_size + 1)
+ return NULL;
+
+ mysalt = salt + crypt_mech->mech->crypt_token_size;
+
+ if(NULL == (temp_hashed_pass = crypt_mech->mech->crypt_function(key, mysalt)))
+ return NULL;
+
+ Debug((DEBUG_DEBUG, "ircd_crypt: untagged pass is %s", temp_hashed_pass));
+
+ /* ok, now we need to prefix the password we just got back
+ with the right tag */
+ if(NULL == (hashed_pass = (char *)MyMalloc(sizeof(char)*strlen(temp_hashed_pass) + crypt_mech->mech->crypt_token_size + 1)))
+ {
+ Debug((DEBUG_MALLOC, "ircd_crypt: unable to allocate memory for temp_hashed_pass"));
+ return NULL;
+ }
+ memset(hashed_pass, 0, sizeof(char)*strlen(temp_hashed_pass)
+ +crypt_mech->mech->crypt_token_size + 1);
+ ircd_strncpy(hashed_pass, crypt_mech->mech->crypt_token,
+ crypt_mech->mech->crypt_token_size);
+ ircd_strncpy(hashed_pass + crypt_mech->mech->crypt_token_size, temp_hashed_pass, strlen(temp_hashed_pass));
+ Debug((DEBUG_DEBUG, "ircd_crypt: tagged pass is %s", hashed_pass));
+ } else {
+ Debug((DEBUG_DEBUG, "ircd_crypt: will try next mechanism at 0x%X",
+ crypt_mech->next));
+ crypt_mech = crypt_mech->next;
+ continue;
+ }
+ return hashed_pass;
+ }
+
+ /* try to use native crypt for an old-style (untagged) password */
+ if (strlen(salt) > 2)
+ {
+ char *s;
+ temp_hashed_pass = (char*)ircd_crypt_native(key, salt);
+ if (!ircd_strcmp(temp_hashed_pass, salt))
+ {
+ DupString(s, temp_hashed_pass);
+ return s;
+ }
+ }
+
+ return NULL;
+}
+
+/** Some basic init.
+ * This function loads initalises the crypt mechanisms linked list and
+ * currently loads the default mechanisms (Salted MD5, Crypt() and PLAIN).
+ * The last step is only needed while ircu is not properly modular.
+ *
+ * When ircu is modular this will be the entry function for the ircd_crypt
+ * module.
+ *
+*/
+void ircd_crypt_init(void)
+{
+
+ if((crypt_mechs_root = MyMalloc(sizeof(crypt_mechs_t))) == NULL)
+ {
+ /* awooga - can't allocate memory for the root structure */
+ Debug((DEBUG_MALLOC, "init_crypt: Could not allocate memory for crypt_mechs_root"));
+ return;
+ }
+
+ crypt_mechs_root->mech = NULL;
+ crypt_mechs_root->next = crypt_mechs_root->prev = NULL;
+
+/* temporary kludge until we're modular. manually call the
+ register functions for crypt mechanisms */
+ ircd_register_crypt_smd5();
+ ircd_register_crypt_plain();
+ ircd_register_crypt_native();
+
+return;
+}