--- /dev/null
+/*
+ * IRC - Internet Relay Chat, ircd/ircd_crypt_smd5.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 Routines for Salted MD5 passwords
+ * @version $Id$
+ *
+ * ircd_crypt_smd5 is largely taken from md5_crypt.c from the Linux PAM
+ * source code. it's been modified to fit in with ircu and some of the
+ * unneeded code has been removed. the source file md5_crypt.c has the
+ * following license, so if any of our opers or admins are in Denmark
+ * they better go buy them a drink ;) -- hikari
+ *
+ * ----------------------------------------------------------------------------
+ * "THE BEER-WARE LICENSE" (Revision 42):
+ * <phk@login.dknet.dk> wrote this file. As long as you retain this notice you
+ * can do whatever you want with this stuff. If we meet some day, and you think
+ * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
+ * ----------------------------------------------------------------------------
+ *
+ */
+#include "config.h"
+#include "ircd_crypt.h"
+#include "ircd_crypt_smd5.h"
+#include "ircd_log.h"
+#include "ircd_md5.h"
+#include "s_debug.h"
+#include "ircd_alloc.h"
+
+/* #include <assert.h> -- Now using assert in ircd_log.h */
+#include <string.h>
+#include <unistd.h>
+
+static unsigned char itoa64[] = /* 0 ... 63 => ascii - 64 */
+"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
+
+/** Converts a binary value into a BASE64 encoded string.
+ * @param s Pointer to the output string
+ * @param v The unsigned long we're working on
+ * @param n The number of bytes we're working with
+ *
+ * This is used to produce the normal MD5 hash everyone is familiar with.
+ * It takes the value v and converts n bytes of it it into an ASCII string in
+ * 6-bit chunks, the resulting string is put at the address pointed to by s.
+ *
+ */
+static void to64(char *s, unsigned long v, int n)
+{
+ while (--n >= 0) {
+ *s++ = itoa64[v & 0x3f];
+ v >>= 6;
+ }
+}
+
+/** Produces a Salted MD5 crypt of a password using the supplied salt
+ * @param key The password we're encrypting
+ * @param salt The salt we're using to encrypt it
+ * @return The Salted MD5 password of key and salt
+ *
+ * Erm does exactly what the brief comment says. If you think I'm writing a
+ * description of how MD5 works, you have another think coming. Go and read
+ * Applied Cryptography by Bruce Schneier. The only difference is we use a
+ * salt at the beginning of the password to perturb it so that the same password
+ * doesn't always produce the same hash.
+ *
+ */
+const char* ircd_crypt_smd5(const char* key, const char* salt)
+{
+const char *magic = "$1$";
+static char passwd[120];
+char *p;
+const char *sp, *ep;
+unsigned char final[16];
+int sl, pl, i, j;
+MD5_CTX ctx, ctx1;
+unsigned long l;
+
+ assert(NULL != key);
+ assert(NULL != salt);
+
+ Debug((DEBUG_DEBUG, "ircd_crypt_smd5: key = %s", key));
+ Debug((DEBUG_DEBUG, "ircd_crypt_smd5: salt = %s", salt));
+
+ /* Refine the Salt first */
+ ep = sp = salt;
+
+ for (ep = sp; *ep && *ep != '$' && ep < (sp + 8); ep++)
+ continue;
+
+ /* get the length of the true salt */
+ sl = ep - sp;
+
+ MD5Init(&ctx);
+
+ /* The password first, since that is what is most unknown */
+ MD5Update(&ctx,(unsigned const char *)key,strlen(key));
+
+ /* Then our magic string */
+ MD5Update(&ctx,(unsigned const char *)magic,strlen(magic));
+
+ /* Then the raw salt */
+ MD5Update(&ctx,(unsigned const char *)sp,sl);
+
+ /* Then just as many characters of the MD5(key,salt,key) */
+ MD5Init(&ctx1);
+ MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
+ MD5Update(&ctx1,(unsigned const char *)sp,sl);
+ MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
+ MD5Final(final,&ctx1);
+ for (pl = strlen(key); pl > 0; pl -= 16)
+ MD5Update(&ctx,(unsigned const char *)final,pl>16 ? 16 : pl);
+
+ /* Don't leave anything around in vm they could use. */
+ memset(final, 0, sizeof final);
+
+ /* Then something really weird... */
+ for (j = 0, i = strlen(key); i; i >>= 1)
+ if (i & 1)
+ MD5Update(&ctx, (unsigned const char *)final+j, 1);
+ else
+ MD5Update(&ctx, (unsigned const char *)key+j, 1);
+
+ /* Now make the output string. */
+ memset(passwd, 0, 120);
+ strncpy(passwd, sp, sl);
+ strcat(passwd, "$");
+
+ MD5Final(final,&ctx);
+
+ /*
+ * and now, just to make sure things don't run too fast
+ * On a 60 Mhz Pentium this takes 34 msec, so you would
+ * need 30 seconds to build a 1000 entry dictionary...
+ */
+ for (i = 0; i < 1000; i++) {
+ MD5Init(&ctx1);
+
+ if (i & 1)
+ MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
+ else
+ MD5Update(&ctx1,(unsigned const char *)final,16);
+
+ if (i % 3)
+ MD5Update(&ctx1,(unsigned const char *)sp,sl);
+
+ if (i % 7)
+ MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
+
+ if (i & 1)
+ MD5Update(&ctx1,(unsigned const char *)final,16);
+ else
+ MD5Update(&ctx1,(unsigned const char *)key,strlen(key));
+
+ MD5Final(final,&ctx1);
+ }
+
+ p = passwd + strlen(passwd);
+
+ Debug((DEBUG_DEBUG, "passwd = %s", passwd));
+
+ /* Turn the encrypted binary data into a BASE64 encoded string we can read
+ * and display -- hikari */
+ l = (final[0] << 16) | (final[6] << 8) | final[12];
+ to64(p, l, 4);
+ p += 4;
+ l = (final[1] << 16) | (final[7] << 8) | final[13];
+ to64(p, l, 4);
+ p += 4;
+ l = (final[2] << 16) | (final[8] << 8) | final[14];
+ to64(p, l, 4);
+ p += 4;
+ l = (final[3] << 16) | (final[9] << 8) | final[15];
+ to64(p, l, 4);
+ p += 4;
+ l = (final[4] << 16) | (final[10] << 8) | final[5];
+ to64(p, l, 4);
+ p += 4;
+ l = final[11];
+ to64(p, l, 2);
+ p += 2;
+ *p = '\0';
+
+ /* Don't leave anything around in vm they could use. */
+ memset(final, 0, sizeof final);
+
+return passwd;
+}
+
+/* end borrowed code */
+
+/** Register ourself with the list of crypt mechanisms
+ * Registers the SMD5 mechanism in the list of available crypt mechanisms. When
+ * we're modular this will be the entry function for the module.
+ *
+ */
+void ircd_register_crypt_smd5(void)
+{
+crypt_mech_t* crypt_mech;
+
+ if ((crypt_mech = (crypt_mech_t*)MyMalloc(sizeof(crypt_mech_t))) == NULL)
+ {
+ Debug((DEBUG_MALLOC, "Could not allocate space for crypt_smd5"));
+ return;
+ }
+
+ crypt_mech->mechname = "smd5";
+ crypt_mech->shortname = "crypt_smd5";
+ crypt_mech->description = "Salted MD5 password hash mechanism.";
+ crypt_mech->crypt_function = &ircd_crypt_smd5;
+ crypt_mech->crypt_token = "$SMD5$";
+ crypt_mech->crypt_token_size = 6 ;
+
+ ircd_crypt_register_mech(crypt_mech);
+
+return;
+}
projects / ircu2.10.12-pk.git / blobdiff