1 /* $OpenBSD: digest-libc.c,v 1.2 2014/02/02 03:44:31 djm 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 19 #include "includes.h" 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 "buffer.h" 32 #include "digest.h" 33 34 typedef void md_init_fn(void *mdctx); 35 typedef void md_update_fn(void *mdctx, const u_int8_t *m, size_t mlen); 36 typedef void md_final_fn(u_int8_t[], void *mdctx); 37 38 struct ssh_digest_ctx { 39 int alg; 40 void *mdctx; 41 }; 42 43 struct ssh_digest { 44 int id; 45 const char *name; 46 size_t block_len; 47 size_t digest_len; 48 size_t ctx_len; 49 md_init_fn *md_init; 50 md_update_fn *md_update; 51 md_final_fn *md_final; 52 }; 53 54 /* NB. Indexed directly by algorithm number */ 55 const struct ssh_digest digests[SSH_DIGEST_MAX] = { 56 { 57 SSH_DIGEST_MD5, 58 "MD5", 59 MD5_BLOCK_LENGTH, 60 MD5_DIGEST_LENGTH, 61 sizeof(MD5_CTX), 62 (md_init_fn *) MD5Init, 63 (md_update_fn *) MD5Update, 64 (md_final_fn *) MD5Final 65 }, 66 { 67 SSH_DIGEST_RIPEMD160, 68 "RIPEMD160", 69 RMD160_BLOCK_LENGTH, 70 RMD160_DIGEST_LENGTH, 71 sizeof(RMD160_CTX), 72 (md_init_fn *) RMD160Init, 73 (md_update_fn *) RMD160Update, 74 (md_final_fn *) RMD160Final 75 }, 76 { 77 SSH_DIGEST_SHA1, 78 "SHA1", 79 SHA1_BLOCK_LENGTH, 80 SHA1_DIGEST_LENGTH, 81 sizeof(SHA1_CTX), 82 (md_init_fn *) SHA1Init, 83 (md_update_fn *) SHA1Update, 84 (md_final_fn *) SHA1Final 85 }, 86 { 87 SSH_DIGEST_SHA256, 88 "SHA256", 89 SHA256_BLOCK_LENGTH, 90 SHA256_DIGEST_LENGTH, 91 sizeof(SHA2_CTX), 92 (md_init_fn *) SHA256Init, 93 (md_update_fn *) SHA256Update, 94 (md_final_fn *) SHA256Final 95 }, 96 { 97 SSH_DIGEST_SHA384, 98 "SHA384", 99 SHA384_BLOCK_LENGTH, 100 SHA384_DIGEST_LENGTH, 101 sizeof(SHA2_CTX), 102 (md_init_fn *) SHA384Init, 103 (md_update_fn *) SHA384Update, 104 (md_final_fn *) SHA384Final 105 }, 106 { 107 SSH_DIGEST_SHA512, 108 "SHA512", 109 SHA512_BLOCK_LENGTH, 110 SHA512_DIGEST_LENGTH, 111 sizeof(SHA2_CTX), 112 (md_init_fn *) SHA512Init, 113 (md_update_fn *) SHA512Update, 114 (md_final_fn *) SHA512Final 115 } 116 }; 117 118 static const struct ssh_digest * 119 ssh_digest_by_alg(int alg) 120 { 121 if (alg < 0 || alg >= SSH_DIGEST_MAX) 122 return NULL; 123 if (digests[alg].id != alg) /* sanity */ 124 return NULL; 125 return &(digests[alg]); 126 } 127 128 size_t 129 ssh_digest_bytes(int alg) 130 { 131 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 132 133 return digest == NULL ? 0 : digest->digest_len; 134 } 135 136 size_t 137 ssh_digest_blocksize(struct ssh_digest_ctx *ctx) 138 { 139 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 140 141 return digest == NULL ? 0 : digest->block_len; 142 } 143 144 struct ssh_digest_ctx * 145 ssh_digest_start(int alg) 146 { 147 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 148 struct ssh_digest_ctx *ret; 149 150 if (digest == NULL || (ret = calloc(1, sizeof(ret))) == NULL) 151 return NULL; 152 if ((ret->mdctx = calloc(1, digest->ctx_len)) == NULL) { 153 free(ret); 154 return NULL; 155 } 156 ret->alg = alg; 157 digest->md_init(ret->mdctx); 158 return ret; 159 } 160 161 int 162 ssh_digest_copy_state(struct ssh_digest_ctx *from, struct ssh_digest_ctx *to) 163 { 164 const struct ssh_digest *digest = ssh_digest_by_alg(from->alg); 165 166 if (digest == NULL || from->alg != to->alg) 167 return -1; 168 memcpy(to->mdctx, from->mdctx, digest->ctx_len); 169 return 0; 170 } 171 172 int 173 ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen) 174 { 175 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 176 177 if (digest == NULL) 178 return -1; 179 digest->md_update(ctx->mdctx, m, mlen); 180 return 0; 181 } 182 183 int 184 ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const Buffer *b) 185 { 186 return ssh_digest_update(ctx, buffer_ptr(b), buffer_len(b)); 187 } 188 189 int 190 ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen) 191 { 192 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 193 194 if (digest == NULL) 195 return -1; 196 if (dlen > UINT_MAX) 197 return -1; 198 if (dlen < digest->digest_len) /* No truncation allowed */ 199 return -1; 200 digest->md_final(d, ctx->mdctx); 201 return 0; 202 } 203 204 void 205 ssh_digest_free(struct ssh_digest_ctx *ctx) 206 { 207 const struct ssh_digest *digest; 208 209 if (ctx != NULL) { 210 digest = ssh_digest_by_alg(ctx->alg); 211 if (digest) { 212 explicit_bzero(ctx->mdctx, digest->ctx_len); 213 free(ctx->mdctx); 214 explicit_bzero(ctx, sizeof(*ctx)); 215 free(ctx); 216 } 217 } 218 } 219 220 int 221 ssh_digest_memory(int alg, const void *m, size_t mlen, u_char *d, size_t dlen) 222 { 223 struct ssh_digest_ctx *ctx = ssh_digest_start(alg); 224 225 if (ctx == NULL) 226 return -1; 227 if (ssh_digest_update(ctx, m, mlen) != 0 || 228 ssh_digest_final(ctx, d, dlen) != 0) 229 return -1; 230 ssh_digest_free(ctx); 231 return 0; 232 } 233 234 int 235 ssh_digest_buffer(int alg, const Buffer *b, u_char *d, size_t dlen) 236 { 237 return ssh_digest_memory(alg, buffer_ptr(b), buffer_len(b), d, dlen); 238 } 239