1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * Copyright 2003 Sun Microsystems, Inc. All rights reserved. 3*0Sstevel@tonic-gate * Use is subject to license terms. 4*0Sstevel@tonic-gate */ 5*0Sstevel@tonic-gate /* 6*0Sstevel@tonic-gate * Copyright (c) 2001 Markus Friedl. All rights reserved. 7*0Sstevel@tonic-gate * 8*0Sstevel@tonic-gate * Redistribution and use in source and binary forms, with or without 9*0Sstevel@tonic-gate * modification, are permitted provided that the following conditions 10*0Sstevel@tonic-gate * are met: 11*0Sstevel@tonic-gate * 1. Redistributions of source code must retain the above copyright 12*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer. 13*0Sstevel@tonic-gate * 2. Redistributions in binary form must reproduce the above copyright 14*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer in the 15*0Sstevel@tonic-gate * documentation and/or other materials provided with the distribution. 16*0Sstevel@tonic-gate * 17*0Sstevel@tonic-gate * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18*0Sstevel@tonic-gate * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19*0Sstevel@tonic-gate * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20*0Sstevel@tonic-gate * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21*0Sstevel@tonic-gate * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22*0Sstevel@tonic-gate * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23*0Sstevel@tonic-gate * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24*0Sstevel@tonic-gate * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25*0Sstevel@tonic-gate * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26*0Sstevel@tonic-gate * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27*0Sstevel@tonic-gate */ 28*0Sstevel@tonic-gate 29*0Sstevel@tonic-gate #include "includes.h" 30*0Sstevel@tonic-gate RCSID("$OpenBSD: mac.c,v 1.5 2002/05/16 22:02:50 markus Exp $"); 31*0Sstevel@tonic-gate 32*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 33*0Sstevel@tonic-gate 34*0Sstevel@tonic-gate #include <openssl/hmac.h> 35*0Sstevel@tonic-gate 36*0Sstevel@tonic-gate #include "xmalloc.h" 37*0Sstevel@tonic-gate #include "getput.h" 38*0Sstevel@tonic-gate #include "log.h" 39*0Sstevel@tonic-gate #include "cipher.h" 40*0Sstevel@tonic-gate #include "kex.h" 41*0Sstevel@tonic-gate #include "mac.h" 42*0Sstevel@tonic-gate 43*0Sstevel@tonic-gate struct { 44*0Sstevel@tonic-gate char *name; 45*0Sstevel@tonic-gate const EVP_MD * (*mdfunc)(void); 46*0Sstevel@tonic-gate int truncatebits; /* truncate digest if != 0 */ 47*0Sstevel@tonic-gate } macs[] = { 48*0Sstevel@tonic-gate { "hmac-sha1", EVP_sha1, 0 }, 49*0Sstevel@tonic-gate { "hmac-sha1-96", EVP_sha1, 96 }, 50*0Sstevel@tonic-gate { "hmac-md5", EVP_md5, 0 }, 51*0Sstevel@tonic-gate { "hmac-md5-96", EVP_md5, 96 }, 52*0Sstevel@tonic-gate #ifdef SOLARIS_SSH_ENABLE_RIPEMD160 53*0Sstevel@tonic-gate { "hmac-ripemd160", EVP_ripemd160, 0 }, 54*0Sstevel@tonic-gate { "hmac-ripemd160@openssh.com", EVP_ripemd160, 0 }, 55*0Sstevel@tonic-gate #endif /* SOLARIS_SSH_ENABLE_RIPEMD160 */ 56*0Sstevel@tonic-gate { NULL, NULL, 0 } 57*0Sstevel@tonic-gate }; 58*0Sstevel@tonic-gate 59*0Sstevel@tonic-gate int 60*0Sstevel@tonic-gate mac_init(Mac *mac, char *name) 61*0Sstevel@tonic-gate { 62*0Sstevel@tonic-gate int i; 63*0Sstevel@tonic-gate for (i = 0; macs[i].name; i++) { 64*0Sstevel@tonic-gate if (strcmp(name, macs[i].name) == 0) { 65*0Sstevel@tonic-gate if (mac != NULL) { 66*0Sstevel@tonic-gate mac->md = (*macs[i].mdfunc)(); 67*0Sstevel@tonic-gate mac->key_len = mac->mac_len = EVP_MD_size(mac->md); 68*0Sstevel@tonic-gate if (macs[i].truncatebits != 0) 69*0Sstevel@tonic-gate mac->mac_len = macs[i].truncatebits/8; 70*0Sstevel@tonic-gate } 71*0Sstevel@tonic-gate debug2("mac_init: found %s", name); 72*0Sstevel@tonic-gate return (0); 73*0Sstevel@tonic-gate } 74*0Sstevel@tonic-gate } 75*0Sstevel@tonic-gate debug2("mac_init: unknown %s", name); 76*0Sstevel@tonic-gate return (-1); 77*0Sstevel@tonic-gate } 78*0Sstevel@tonic-gate 79*0Sstevel@tonic-gate u_char * 80*0Sstevel@tonic-gate mac_compute(Mac *mac, u_int32_t seqno, u_char *data, int datalen) 81*0Sstevel@tonic-gate { 82*0Sstevel@tonic-gate HMAC_CTX c; 83*0Sstevel@tonic-gate static u_char m[EVP_MAX_MD_SIZE]; 84*0Sstevel@tonic-gate u_char b[4]; 85*0Sstevel@tonic-gate 86*0Sstevel@tonic-gate if (mac->key == NULL) 87*0Sstevel@tonic-gate fatal("mac_compute: no key"); 88*0Sstevel@tonic-gate if (mac->mac_len > sizeof(m)) 89*0Sstevel@tonic-gate fatal("mac_compute: mac too long"); 90*0Sstevel@tonic-gate HMAC_Init(&c, mac->key, mac->key_len, mac->md); 91*0Sstevel@tonic-gate PUT_32BIT(b, seqno); 92*0Sstevel@tonic-gate HMAC_Update(&c, b, sizeof(b)); 93*0Sstevel@tonic-gate HMAC_Update(&c, data, datalen); 94*0Sstevel@tonic-gate HMAC_Final(&c, m, NULL); 95*0Sstevel@tonic-gate HMAC_cleanup(&c); 96*0Sstevel@tonic-gate return (m); 97*0Sstevel@tonic-gate } 98*0Sstevel@tonic-gate 99*0Sstevel@tonic-gate /* XXX copied from ciphers_valid */ 100*0Sstevel@tonic-gate #define MAC_SEP "," 101*0Sstevel@tonic-gate int 102*0Sstevel@tonic-gate mac_valid(const char *names) 103*0Sstevel@tonic-gate { 104*0Sstevel@tonic-gate char *maclist, *cp, *p; 105*0Sstevel@tonic-gate 106*0Sstevel@tonic-gate if (names == NULL || strcmp(names, "") == 0) 107*0Sstevel@tonic-gate return (0); 108*0Sstevel@tonic-gate maclist = cp = xstrdup(names); 109*0Sstevel@tonic-gate for ((p = strsep(&cp, MAC_SEP)); p && *p != '\0'; 110*0Sstevel@tonic-gate (p = strsep(&cp, MAC_SEP))) { 111*0Sstevel@tonic-gate if (mac_init(NULL, p) < 0) { 112*0Sstevel@tonic-gate debug("bad mac %s [%s]", p, names); 113*0Sstevel@tonic-gate xfree(maclist); 114*0Sstevel@tonic-gate return (0); 115*0Sstevel@tonic-gate } else { 116*0Sstevel@tonic-gate debug3("mac ok: %s [%s]", p, names); 117*0Sstevel@tonic-gate } 118*0Sstevel@tonic-gate } 119*0Sstevel@tonic-gate debug3("macs ok: [%s]", names); 120*0Sstevel@tonic-gate xfree(maclist); 121*0Sstevel@tonic-gate return (1); 122*0Sstevel@tonic-gate } 123