1 /* $OpenBSD: digest-libc.c,v 1.7 2020/02/26 13:40:09 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 19 #include "includes.h" 20 21 #ifndef WITH_OPENSSL 22 23 #include <sys/types.h> 24 #include <limits.h> 25 #include <stdlib.h> 26 #include <string.h> 27 28 #if 0 29 #include <md5.h> 30 #include <rmd160.h> 31 #endif 32 #ifdef HAVE_SHA1_H 33 #include <sha1.h> 34 #endif 35 #ifdef HAVE_SHA2_H 36 #include <sha2.h> 37 #endif 38 39 #include "ssherr.h" 40 #include "sshbuf.h" 41 #include "digest.h" 42 43 typedef void md_init_fn(void *mdctx); 44 typedef void md_update_fn(void *mdctx, const u_int8_t *m, size_t mlen); 45 typedef void md_final_fn(u_int8_t[], void *mdctx); 46 47 struct ssh_digest_ctx { 48 int alg; 49 void *mdctx; 50 }; 51 52 struct ssh_digest { 53 int id; 54 const char *name; 55 size_t block_len; 56 size_t digest_len; 57 size_t ctx_len; 58 md_init_fn *md_init; 59 md_update_fn *md_update; 60 md_final_fn *md_final; 61 }; 62 63 /* NB. Indexed directly by algorithm number */ 64 const struct ssh_digest digests[SSH_DIGEST_MAX] = { 65 { 66 SSH_DIGEST_MD5, 67 "MD5", 68 MD5_BLOCK_LENGTH, 69 MD5_DIGEST_LENGTH, 70 sizeof(MD5_CTX), 71 (md_init_fn *) MD5Init, 72 (md_update_fn *) MD5Update, 73 (md_final_fn *) MD5Final 74 }, 75 { 76 SSH_DIGEST_SHA1, 77 "SHA1", 78 SHA1_BLOCK_LENGTH, 79 SHA1_DIGEST_LENGTH, 80 sizeof(SHA1_CTX), 81 (md_init_fn *) SHA1Init, 82 (md_update_fn *) SHA1Update, 83 (md_final_fn *) SHA1Final 84 }, 85 { 86 SSH_DIGEST_SHA256, 87 "SHA256", 88 SHA256_BLOCK_LENGTH, 89 SHA256_DIGEST_LENGTH, 90 sizeof(SHA2_CTX), 91 (md_init_fn *) SHA256Init, 92 (md_update_fn *) SHA256Update, 93 (md_final_fn *) SHA256Final 94 }, 95 { 96 SSH_DIGEST_SHA384, 97 "SHA384", 98 SHA384_BLOCK_LENGTH, 99 SHA384_DIGEST_LENGTH, 100 sizeof(SHA2_CTX), 101 (md_init_fn *) SHA384Init, 102 (md_update_fn *) SHA384Update, 103 (md_final_fn *) SHA384Final 104 }, 105 { 106 SSH_DIGEST_SHA512, 107 "SHA512", 108 SHA512_BLOCK_LENGTH, 109 SHA512_DIGEST_LENGTH, 110 sizeof(SHA2_CTX), 111 (md_init_fn *) SHA512Init, 112 (md_update_fn *) SHA512Update, 113 (md_final_fn *) SHA512Final 114 } 115 }; 116 117 static const struct ssh_digest * 118 ssh_digest_by_alg(int alg) 119 { 120 if (alg < 0 || alg >= SSH_DIGEST_MAX) 121 return NULL; 122 if (digests[alg].id != alg) /* sanity */ 123 return NULL; 124 return &(digests[alg]); 125 } 126 127 int 128 ssh_digest_alg_by_name(const char *name) 129 { 130 int alg; 131 132 for (alg = 0; alg < SSH_DIGEST_MAX; alg++) { 133 if (strcasecmp(name, digests[alg].name) == 0) 134 return digests[alg].id; 135 } 136 return -1; 137 } 138 139 const char * 140 ssh_digest_alg_name(int alg) 141 { 142 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 143 144 return digest == NULL ? NULL : digest->name; 145 } 146 147 size_t 148 ssh_digest_bytes(int alg) 149 { 150 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 151 152 return digest == NULL ? 0 : digest->digest_len; 153 } 154 155 size_t 156 ssh_digest_blocksize(struct ssh_digest_ctx *ctx) 157 { 158 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 159 160 return digest == NULL ? 0 : digest->block_len; 161 } 162 163 struct ssh_digest_ctx * 164 ssh_digest_start(int alg) 165 { 166 const struct ssh_digest *digest = ssh_digest_by_alg(alg); 167 struct ssh_digest_ctx *ret; 168 169 if (digest == NULL || (ret = calloc(1, sizeof(*ret))) == NULL) 170 return NULL; 171 if ((ret->mdctx = calloc(1, digest->ctx_len)) == NULL) { 172 free(ret); 173 return NULL; 174 } 175 ret->alg = alg; 176 digest->md_init(ret->mdctx); 177 return ret; 178 } 179 180 int 181 ssh_digest_copy_state(struct ssh_digest_ctx *from, struct ssh_digest_ctx *to) 182 { 183 const struct ssh_digest *digest = ssh_digest_by_alg(from->alg); 184 185 if (digest == NULL || from->alg != to->alg) 186 return SSH_ERR_INVALID_ARGUMENT; 187 memcpy(to->mdctx, from->mdctx, digest->ctx_len); 188 return 0; 189 } 190 191 int 192 ssh_digest_update(struct ssh_digest_ctx *ctx, const void *m, size_t mlen) 193 { 194 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 195 196 if (digest == NULL) 197 return SSH_ERR_INVALID_ARGUMENT; 198 digest->md_update(ctx->mdctx, m, mlen); 199 return 0; 200 } 201 202 int 203 ssh_digest_update_buffer(struct ssh_digest_ctx *ctx, const struct sshbuf *b) 204 { 205 return ssh_digest_update(ctx, sshbuf_ptr(b), sshbuf_len(b)); 206 } 207 208 int 209 ssh_digest_final(struct ssh_digest_ctx *ctx, u_char *d, size_t dlen) 210 { 211 const struct ssh_digest *digest = ssh_digest_by_alg(ctx->alg); 212 213 if (digest == NULL) 214 return SSH_ERR_INVALID_ARGUMENT; 215 if (dlen > UINT_MAX) 216 return SSH_ERR_INVALID_ARGUMENT; 217 if (dlen < digest->digest_len) /* No truncation allowed */ 218 return SSH_ERR_INVALID_ARGUMENT; 219 digest->md_final(d, ctx->mdctx); 220 return 0; 221 } 222 223 void 224 ssh_digest_free(struct ssh_digest_ctx *ctx) 225 { 226 const struct ssh_digest *digest; 227 228 if (ctx != NULL) { 229 digest = ssh_digest_by_alg(ctx->alg); 230 if (digest) { 231 explicit_bzero(ctx->mdctx, digest->ctx_len); 232 free(ctx->mdctx); 233 freezero(ctx, sizeof(*ctx)); 234 } 235 } 236 } 237 238 int 239 ssh_digest_memory(int alg, const void *m, size_t mlen, u_char *d, size_t dlen) 240 { 241 struct ssh_digest_ctx *ctx = ssh_digest_start(alg); 242 243 if (ctx == NULL) 244 return SSH_ERR_INVALID_ARGUMENT; 245 if (ssh_digest_update(ctx, m, mlen) != 0 || 246 ssh_digest_final(ctx, d, dlen) != 0) 247 return SSH_ERR_INVALID_ARGUMENT; 248 ssh_digest_free(ctx); 249 return 0; 250 } 251 252 int 253 ssh_digest_buffer(int alg, const struct sshbuf *b, u_char *d, size_t dlen) 254 { 255 return ssh_digest_memory(alg, sshbuf_ptr(b), sshbuf_len(b), d, dlen); 256 } 257 #endif /* !WITH_OPENSSL */ 258