1/* $NetBSD: mech_crammd5.c,v 1.4 2011/02/12 23:21:32 christos Exp $ */ 2 3/* Copyright (c) 2010 The NetBSD Foundation, Inc. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to The NetBSD Foundation 7 * by Mateusz Kocielski. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by the NetBSD 20 * Foundation, Inc. and its contributors. 21 * 4. Neither the name of The NetBSD Foundation nor the names of its 22 * contributors may be used to endorse or promote products derived 23 * from this software without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37#include <sys/cdefs.h> 38__RCSID("$NetBSD: mech_crammd5.c,v 1.4 2011/02/12 23:21:32 christos Exp $"); 39 40#include <sys/param.h> 41 42#include <saslc.h> 43#include <stdio.h> 44#include <stdlib.h> 45#include <string.h> 46 47#include "crypto.h" 48#include "mech.h" 49#include "saslc_private.h" 50 51 52/* See RFC 2195. */ 53 54/* properties */ 55#define SASLC_CRAMMD5_AUTHCID SASLC_PROP_AUTHCID 56#define SASLC_CRAMMD5_PASSWD SASLC_PROP_PASSWD 57 58/** 59 * @brief do one step of the sasl authentication 60 * @param sess sasl session 61 * @param in input data 62 * @param inlen input data length 63 * @param out place to store output data 64 * @param outlen output data length 65 * @return MECH_OK - success, 66 * MECH_STEP - more steps are needed, 67 * MECH_ERROR - error 68 */ 69static int 70saslc__mech_crammd5_cont(saslc_sess_t *sess, const void *in, size_t inlen, 71 void **out, size_t *outlen) 72{ 73 const char *authcid, *passwd; 74 char *digest, *name; 75 int len, rv; 76 77 /* in case we are called before getting challenge from server */ 78 if (inlen == 0) { 79 *out = NULL; 80 *outlen = 0; 81 return MECH_STEP; 82 } 83 if ((authcid = saslc_sess_getprop(sess, SASLC_CRAMMD5_AUTHCID)) 84 == NULL) { 85 saslc__error_set(ERR(sess), ERROR_MECH, 86 "authcid is required for an authentication"); 87 return MECH_ERROR; 88 } 89 if ((passwd = saslc_sess_getprop(sess, SASLC_CRAMMD5_PASSWD)) 90 == NULL) { 91 saslc__error_set(ERR(sess), ERROR_MECH, 92 "passwd is required for an authentication"); 93 return MECH_ERROR; 94 } 95 digest = saslc__crypto_hmac_md5_hex((const unsigned char *)passwd, 96 strlen(passwd), in, inlen); 97 if (digest == NULL) { 98 saslc__error_set_errno(ERR(sess), ERROR_NOMEM); 99 return MECH_ERROR; 100 } 101 if ((len = asprintf(&name, "%s %s", authcid, digest)) == -1) { 102 saslc__error_set_errno(ERR(sess), ERROR_NOMEM); 103 rv = MECH_ERROR; 104 } 105 else { 106 *out = name; 107 *outlen = len; /* don't count the '\0' byte */ 108 rv = MECH_OK; 109 } 110 memset(digest, 0, HMAC_MD5_DIGEST_LENGTH); 111 free(digest); 112 return rv; 113} 114 115/* mechanism definition */ 116const saslc__mech_t saslc__mech_crammd5 = { 117 .name = "CRAM-MD5", 118 .flags = FLAG_DICTIONARY, 119 .create = saslc__mech_generic_create, 120 .cont = saslc__mech_crammd5_cont, 121 .encode = NULL, 122 .decode = NULL, 123 .destroy = saslc__mech_generic_destroy 124}; 125