1 /* $OpenBSD: digest-libc.c,v 1.5 2015/05/05 02:48:17 jsg Exp $ */ 2 /* 3 * Copyright (c) 2013 Damien Miller <djm@mindrot.org> 4 * Copyright (c) 2014 Markus Friedl. All rights reserved. 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 #include "includes.h" 19 __RCSID("$NetBSD: digest-libc.c,v 1.4 2015/07/03 01:00:00 christos Exp $"); 20 21 #include <sys/types.h> 22 #include <limits.h> 23 #include <stdlib.h> 24 #include <string.h> 25 26 #include <md5.h> 27 #include <rmd160.h> 28 #include <sha1.h> 29 #include <sha2.h> 30 31 #include "ssherr.h" 32 #include "sshbuf.h" 33 #include "digest.h" 34 35 typedef void md_init_fn(void *mdctx); 36 typedef void md_update_fn(void *mdctx, const u_int8_t *m, size_t mlen); 37 typedef void md_final_fn(u_int8_t[], void *mdctx); 38 39 struct ssh_digest_ctx { 40 int alg; 41 void *mdctx; 42 }; 43 44 struct ssh_digest { 45 int id; 46 const char *name; 47 size_t block_len; 48 size_t digest_len; 49 size_t ctx_len; 50 md_init_fn *md_init; 51 md_update_fn *md_update; 52 md_final_fn *md_final; 53 }; 54 55 /* NB. Indexed directly by algorithm number */ 56 const struct ssh_digest digests[SSH_DIGEST_MAX] = { 57 { 58 SSH_DIGEST_MD5, 59 "MD5", 60 MD5_BLOCK_LENGTH, 61 MD5_DIGEST_LENGTH, 62 sizeof(MD5_CTX), 63 (md_init_fn *) MD5Init, 64 (md_update_fn *) MD5Update, 65 (md_final_fn *) MD5Final 66 }, 67 { 68 SSH_DIGEST_RIPEMD160, 69 "RIPEMD160", 70 RMD160_BLOCK_LENGTH, 71 RMD160_DIGEST_LENGTH, 72 sizeof(RMD160_CTX), 73 (md_init_fn *) RMD160Init, 74 (md_update_fn *) RMD160Update, 75 (md_final_fn *) RMD160Final 76 }, 77 { 78 SSH_DIGEST_SHA1, 79 "SHA1", 80 SHA1_BLOCK_LENGTH, 81 SHA1_DIGEST_LENGTH, 82 sizeof(SHA1_CTX), 83 (md_init_fn *) SHA1Init, 84 (md_update_fn *) SHA1Update, 85 (md_final_fn *) SHA1Final 86 }, 87 { 88 SSH_DIGEST_SHA256, 89 "SHA256", 90 SHA256_BLOCK_LENGTH, 91 SHA256_DIGEST_LENGTH, 92 sizeof(SHA2_CTX), 93 (md_init_fn *) SHA256Init, 94 (md_update_fn *) SHA256Update, 95 (md_final_fn *) SHA256Final 96 }, 97 { 98 SSH_DIGEST_SHA384, 99 "SHA384", 100 SHA384_BLOCK_LENGTH, 101 SHA384_DIGEST_LENGTH, 102 sizeof(SHA2_CTX), 103 (md_init_fn *) SHA384Init, 104 (md_update_fn *) SHA384Update, 105 (md_final_fn *) SHA384Final 106 }, 107 { 108 SSH_DIGEST_SHA512, 109 "SHA512", 110 SHA512_BLOCK_LENGTH, 111 SHA512_DIGEST_LENGTH, 112 sizeof(SHA2_CTX), 113 (md_init_fn *) SHA512Init, 114 (md_update_fn *) SHA512Update, 115 (md_final_fn *) SHA512Final 116 } 117 }; 118 119 static const struct ssh_digest * 120 ssh_digest_by_alg(int alg) 121 { 122 if (alg < 0 || alg >= SSH_DIGEST_MAX) 123 return NULL; 124 if (digests[alg].id != alg) /* sanity */ 125 return NULL; 126 return &(digests[alg]); 127 } 128 129 int 130 ssh_digest_alg_by_name(const char *name) 131 { 132 int alg; 133 134 for (alg = 0; alg < SSH_DIGEST_MAX; alg++) { 135 if (strcasecmp(name, digests[alg].name) == 0) 136 return digests[alg].id; 137 } 138 return -1; 139 } 140 141 const char * 142 ssh_digest_alg_name(int alg) 143 { 144 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 145 146 return digest == NULL ? NULL : digest->name; 147 } 148 149 size_t 150 ssh_digest_bytes(int alg) 151 { 152 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 153 154 return digest == NULL ? 0 : digest->digest_len; 155 } 156 157 size_t 158 ssh_digest_blocksize(struct ssh_digest_ctx *ctx) 159 { 160 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 161 162 return digest == NULL ? 0 : digest->block_len; 163 } 164 165 struct ssh_digest_ctx * 166 ssh_digest_start(int alg) 167 { 168 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 169 struct ssh_digest_ctx *ret; 170 171 if (digest == NULL || (ret = calloc(1, sizeof(*ret))) == NULL) 172 return NULL; 173 if ((ret->mdctx = calloc(1, digest->ctx_len)) == NULL) { 174 free(ret); 175 return NULL; 176 } 177 ret->alg = alg; 178 digest->md_init(ret->mdctx); 179 return ret; 180 } 181 182 int 183 ssh_digest_copy_state(struct ssh_digest_ctx *from, struct ssh_digest_ctx *to) 184 { 185 const struct ssh_digest *digest = ssh_digest_by_alg(from->alg); 186 187 if (digest == NULL || from->alg != to->alg) 188 return SSH_ERR_INVALID_ARGUMENT; 189 memcpy(to->mdctx, from->mdctx, digest->ctx_len); 190 return 0; 191 } 192 193 int 194 ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen) 195 { 196 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 197 198 if (digest == NULL) 199 return SSH_ERR_INVALID_ARGUMENT; 200 digest->md_update(ctx->mdctx, m, mlen); 201 return 0; 202 } 203 204 int 205 ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const struct sshbuf *b) 206 { 207 return ssh_digest_update(ctx, sshbuf_ptr(b), sshbuf_len(b)); 208 } 209 210 int 211 ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen) 212 { 213 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 214 215 if (digest == NULL) 216 return SSH_ERR_INVALID_ARGUMENT; 217 if (dlen > UINT_MAX) 218 return SSH_ERR_INVALID_ARGUMENT; 219 if (dlen < digest->digest_len) /* No truncation allowed */ 220 return SSH_ERR_INVALID_ARGUMENT; 221 digest->md_final(d, ctx->mdctx); 222 return 0; 223 } 224 225 void 226 ssh_digest_free(struct ssh_digest_ctx *ctx) 227 { 228 const struct ssh_digest *digest; 229 230 if (ctx != NULL) { 231 digest = ssh_digest_by_alg(ctx->alg); 232 if (digest) { 233 explicit_bzero(ctx->mdctx, digest->ctx_len); 234 free(ctx->mdctx); 235 explicit_bzero(ctx, sizeof(*ctx)); 236 free(ctx); 237 } 238 } 239 } 240 241 int 242 ssh_digest_memory(int alg, const void *m, size_t mlen, u_char *d, size_t dlen) 243 { 244 struct ssh_digest_ctx *ctx = ssh_digest_start(alg); 245 246 if (ctx == NULL) 247 return SSH_ERR_INVALID_ARGUMENT; 248 if (ssh_digest_update(ctx, m, mlen) != 0 || 249 ssh_digest_final(ctx, d, dlen) != 0) 250 return SSH_ERR_INVALID_ARGUMENT; 251 ssh_digest_free(ctx); 252 return 0; 253 } 254 255 int 256 ssh_digest_buffer(int alg, const struct sshbuf *b, u_char *d, size_t dlen) 257 { 258 return ssh_digest_memory(alg, sshbuf_ptr(b), sshbuf_len(b), d, dlen); 259 } 260