11305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood/* $OpenBSD: mac.c,v 1.16 2011/08/02 01:22:11 djm Exp $ */ 21305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood/* 31305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * Copyright (c) 2001 Markus Friedl. All rights reserved. 41305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * 51305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * Redistribution and use in source and binary forms, with or without 61305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * modification, are permitted provided that the following conditions 71305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * are met: 81305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * 1. Redistributions of source code must retain the above copyright 91305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * notice, this list of conditions and the following disclaimer. 101305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * 2. Redistributions in binary form must reproduce the above copyright 111305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * notice, this list of conditions and the following disclaimer in the 121305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * documentation and/or other materials provided with the distribution. 131305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * 141305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 151305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 161305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 171305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 181305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 191305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 201305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 211305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 221305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 231305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 241305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood */ 251305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 261305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "includes.h" 271305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 281305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include <sys/types.h> 291305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 301305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include <openssl/hmac.h> 311305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 321305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include <stdarg.h> 331305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include <string.h> 341305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include <signal.h> 351305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 361305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "xmalloc.h" 371305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "log.h" 381305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "cipher.h" 391305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "buffer.h" 401305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "key.h" 411305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "kex.h" 421305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "mac.h" 431305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "misc.h" 441305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 451305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#include "umac.h" 461305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 471305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#define SSH_EVP 1 /* OpenSSL EVP-based MAC */ 481305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#define SSH_UMAC 2 /* UMAC (not integrated with OpenSSL) */ 491305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 501305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodstruct { 511305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood char *name; 521305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood int type; 531305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood const EVP_MD * (*mdfunc)(void); 541305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood int truncatebits; /* truncate digest if != 0 */ 551305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood int key_len; /* just for UMAC */ 561305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood int len; /* just for UMAC */ 571305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood} macs[] = { 581305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-sha1", SSH_EVP, EVP_sha1, 0, -1, -1 }, 591305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-sha1-96", SSH_EVP, EVP_sha1, 96, -1, -1 }, 601305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#ifdef HAVE_EVP_SHA256 611305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-sha2-256", SSH_EVP, EVP_sha256, 0, -1, -1 }, 621305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-sha2-256-96", SSH_EVP, EVP_sha256, 96, -1, -1 }, 631305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-sha2-512", SSH_EVP, EVP_sha512, 0, -1, -1 }, 641305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-sha2-512-96", SSH_EVP, EVP_sha512, 96, -1, -1 }, 651305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#endif 661305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-md5", SSH_EVP, EVP_md5, 0, -1, -1 }, 671305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-md5-96", SSH_EVP, EVP_md5, 96, -1, -1 }, 681305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-ripemd160", SSH_EVP, EVP_ripemd160, 0, -1, -1 }, 691305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "hmac-ripemd160@openssh.com", SSH_EVP, EVP_ripemd160, 0, -1, -1 }, 701305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { "umac-64@openssh.com", SSH_UMAC, NULL, 0, 128, 64 }, 711305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood { NULL, 0, NULL, 0, -1, -1 } 721305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood}; 731305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 741305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodstatic void 751305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodmac_setup_by_id(Mac *mac, int which) 761305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood{ 771305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood int evp_len; 781305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->type = macs[which].type; 791305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (mac->type == SSH_EVP) { 801305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->evp_md = (*macs[which].mdfunc)(); 811305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if ((evp_len = EVP_MD_size(mac->evp_md)) <= 0) 821305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood fatal("mac %s len %d", mac->name, evp_len); 831305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->key_len = mac->mac_len = (u_int)evp_len; 841305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } else { 851305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->mac_len = macs[which].len / 8; 861305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->key_len = macs[which].key_len / 8; 871305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->umac_ctx = NULL; 881305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } 891305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (macs[which].truncatebits != 0) 901305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->mac_len = macs[which].truncatebits / 8; 911305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood} 921305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 931305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodint 941305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodmac_setup(Mac *mac, char *name) 951305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood{ 961305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood int i; 971305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 981305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood for (i = 0; macs[i].name; i++) { 991305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (strcmp(name, macs[i].name) == 0) { 1001305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (mac != NULL) 1011305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac_setup_by_id(mac, i); 1021305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood debug2("mac_setup: found %s", name); 1031305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return (0); 1041305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } 1051305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } 1061305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood debug2("mac_setup: unknown %s", name); 1071305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return (-1); 1081305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood} 1091305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 1101305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodint 1111305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodmac_init(Mac *mac) 1121305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood{ 1131305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (mac->key == NULL) 1141305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood fatal("mac_init: no key"); 1151305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood switch (mac->type) { 1161305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood case SSH_EVP: 1171305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (mac->evp_md == NULL) 1181305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return -1; 1191305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood HMAC_Init(&mac->evp_ctx, mac->key, mac->key_len, mac->evp_md); 1201305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return 0; 1211305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood case SSH_UMAC: 1221305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->umac_ctx = umac_new(mac->key); 1231305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return 0; 1241305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood default: 1251305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return -1; 1261305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } 1271305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood} 1281305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 1291305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodu_char * 1301305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodmac_compute(Mac *mac, u_int32_t seqno, u_char *data, int datalen) 1311305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood{ 1321305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood static u_char m[EVP_MAX_MD_SIZE]; 1331305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood u_char b[4], nonce[8]; 1341305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 1351305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (mac->mac_len > sizeof(m)) 1361305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood fatal("mac_compute: mac too long %u %lu", 1371305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->mac_len, (u_long)sizeof(m)); 1381305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 1391305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood switch (mac->type) { 1401305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood case SSH_EVP: 1411305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood put_u32(b, seqno); 1421305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood /* reset HMAC context */ 1431305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood HMAC_Init(&mac->evp_ctx, NULL, 0, NULL); 1441305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood HMAC_Update(&mac->evp_ctx, b, sizeof(b)); 1451305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood HMAC_Update(&mac->evp_ctx, data, datalen); 1461305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood HMAC_Final(&mac->evp_ctx, m, NULL); 1471305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood break; 1481305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood case SSH_UMAC: 1491305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood put_u64(nonce, seqno); 1501305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood umac_update(mac->umac_ctx, data, datalen); 1511305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood umac_final(mac->umac_ctx, m, nonce); 1521305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood break; 1531305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood default: 1541305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood fatal("mac_compute: unknown MAC type"); 1551305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } 1561305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return (m); 1571305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood} 1581305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 1591305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodvoid 1601305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodmac_clear(Mac *mac) 1611305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood{ 1621305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (mac->type == SSH_UMAC) { 1631305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (mac->umac_ctx != NULL) 1641305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood umac_delete(mac->umac_ctx); 1651305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } else if (mac->evp_md != NULL) 1661305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood HMAC_cleanup(&mac->evp_ctx); 1671305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->evp_md = NULL; 1681305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood mac->umac_ctx = NULL; 1691305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood} 1701305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 1711305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood/* XXX copied from ciphers_valid */ 1721305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood#define MAC_SEP "," 1731305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodint 1741305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwoodmac_valid(const char *names) 1751305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood{ 1761305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood char *maclist, *cp, *p; 1771305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood 1781305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (names == NULL || strcmp(names, "") == 0) 1791305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return (0); 1801305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood maclist = cp = xstrdup(names); 1811305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood for ((p = strsep(&cp, MAC_SEP)); p && *p != '\0'; 1821305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood (p = strsep(&cp, MAC_SEP))) { 1831305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood if (mac_setup(NULL, p) < 0) { 1841305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood debug("bad mac %s [%s]", p, names); 1851305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood xfree(maclist); 1861305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return (0); 1871305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } else { 1881305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood debug3("mac ok: %s [%s]", p, names); 1891305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } 1901305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood } 1911305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood debug3("macs ok: [%s]", names); 1921305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood xfree(maclist); 1931305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood return (1); 1941305e95ba6ff9fa202d0818caf10405df4b0f648Mike Lockwood} 195