1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* 27 * Portions of this code from crypt_bsdmd5.so (bsdmd5.c) : 28 * ---------------------------------------------------------------------------- 29 * "THE BEER-WARE LICENSE" (Revision 42): 30 * <phk@login.dknet.dk> wrote this file. As long as you retain this notice you 31 * can do whatever you want with this stuff. If we meet some day, and you think 32 * this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp 33 * ---------------------------------------------------------------------------- 34 * 35 * $FreeBSD: crypt.c,v 1.5 1996/10/14 08:34:02 phk Exp $ 36 * 37 */ 38 39 /* 40 * Implements the specification from: 41 * 42 * From http://people.redhat.com/drepper/SHA-crypt.txt 43 * 44 * Portions of the code taken from inspired by or verified against the 45 * source in the above document which is licensed as: 46 * 47 * "Released into the Public Domain by Ulrich Drepper <drepper@redhat.com>." 48 */ 49 50 51 #include <sys/types.h> 52 #include <sys/stat.h> 53 #include <sys/sysmacros.h> 54 #include <fcntl.h> 55 #include <unistd.h> 56 #include <string.h> 57 #include <stdio.h> 58 #include <errno.h> 59 #include <stdlib.h> 60 #include <alloca.h> 61 62 #include <sha2.h> 63 #include <crypt.h> 64 65 #define MAX_SALT_LEN 16 66 #define ROUNDS_DEFAULT 5000 67 #define ROUNDS_MIN 1000 68 #define ROUNDS_MAX 999999999 69 70 #ifdef CRYPT_SHA256 71 72 #define DIGEST_CTX SHA256_CTX 73 #define DIGESTInit SHA256Init 74 #define DIGESTUpdate SHA256Update 75 #define DIGESTFinal SHA256Final 76 #define DIGEST_LEN SHA256_DIGEST_LENGTH 77 #define MIXCHARS 32 78 static const char crypt_alg_magic[] = "$5"; 79 80 #elif CRYPT_SHA512 81 82 #define DIGEST_CTX SHA512_CTX 83 #define DIGESTInit SHA512Init 84 #define DIGESTUpdate SHA512Update 85 #define DIGESTFinal SHA512Final 86 #define DIGEST_LEN SHA512_DIGEST_LENGTH 87 #define MIXCHARS 64 88 static const char crypt_alg_magic[] = "$6"; 89 90 #else 91 #error "One of CRYPT_256 or CRYPT_512 must be defined" 92 #endif 93 94 static const int crypt_alg_magic_len = sizeof (crypt_alg_magic) - 1; 95 96 97 static uchar_t b64t[] = /* 0 ... 63 => ascii - 64 */ 98 "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"; 99 100 #define b64_from_24bit(B2, B1, B0, N) \ 101 { \ 102 uint_t w = ((B2) << 16) | ((B1) << 8) | (B0); \ 103 int n = (N); \ 104 while (--n >= 0 && ctbufflen > 0) { \ 105 *p++ = b64t[w & 0x3f]; \ 106 w >>= 6; \ 107 ctbufflen--; \ 108 } \ 109 } 110 111 static void 112 to64(char *s, uint64_t v, int n) 113 { 114 while (--n >= 0) { 115 *s++ = b64t[v&0x3f]; 116 v >>= 6; 117 } 118 } 119 120 #define ROUNDS "rounds=" 121 #define ROUNDSLEN (sizeof (ROUNDS) - 1) 122 123 /* 124 * get the integer value after rounds= where ever it occurs in the string. 125 * if the last char after the int is a , or $ that is fine anything else is an 126 * error. 127 */ 128 static uint32_t 129 getrounds(const char *s) 130 { 131 char *r, *p, *e; 132 long val; 133 134 if (s == NULL) 135 return (0); 136 137 if ((r = strstr(s, ROUNDS)) == NULL) { 138 return (0); 139 } 140 141 if (strncmp(r, ROUNDS, ROUNDSLEN) != 0) { 142 return (0); 143 } 144 145 p = r + ROUNDSLEN; 146 errno = 0; 147 val = strtol(p, &e, 10); 148 /* 149 * An error occured or there is non-numeric stuff at the end 150 * which isn't one of the crypt(3c) special chars ',' or '$' 151 */ 152 if (errno != 0 || val < 0 || 153 !(*e == '\0' || *e == ',' || *e == '$')) { 154 return (0); 155 } 156 157 return ((uint32_t)val); 158 } 159 160 161 char * 162 crypt_genhash_impl(char *ctbuffer, 163 size_t ctbufflen, 164 const char *plaintext, 165 const char *switchsalt, 166 const char **params) 167 { 168 int salt_len, plaintext_len, i; 169 char *salt; 170 uchar_t A[DIGEST_LEN]; 171 uchar_t B[DIGEST_LEN]; 172 uchar_t DP[DIGEST_LEN]; 173 uchar_t DS[DIGEST_LEN]; 174 DIGEST_CTX ctxA, ctxB, ctxC, ctxDP, ctxDS; 175 int rounds = ROUNDS_DEFAULT; 176 int srounds = 0; 177 boolean_t custom_rounds = B_FALSE; 178 char *p; 179 char *P, *Pp; 180 char *S, *Sp; 181 182 /* Refine the salt */ 183 salt = (char *)switchsalt; 184 185 /* skip our magic string */ 186 if (strncmp((char *)salt, crypt_alg_magic, crypt_alg_magic_len) == 0) { 187 salt += crypt_alg_magic_len + 1; 188 } 189 190 srounds = getrounds(salt); 191 if (srounds != 0) { 192 rounds = MAX(ROUNDS_MIN, MIN(srounds, ROUNDS_MAX)); 193 custom_rounds = B_TRUE; 194 p = strchr(salt, '$'); 195 if (p != NULL) 196 salt = p + 1; 197 } 198 199 salt_len = MIN(strcspn(salt, "$"), MAX_SALT_LEN); 200 plaintext_len = strlen(plaintext); 201 202 /* 1. */ 203 DIGESTInit(&ctxA); 204 205 /* 2. The password first, since that is what is most unknown */ 206 DIGESTUpdate(&ctxA, plaintext, plaintext_len); 207 208 /* 3. Then the raw salt */ 209 DIGESTUpdate(&ctxA, salt, salt_len); 210 211 /* 4. - 8. */ 212 DIGESTInit(&ctxB); 213 DIGESTUpdate(&ctxB, plaintext, plaintext_len); 214 DIGESTUpdate(&ctxB, salt, salt_len); 215 DIGESTUpdate(&ctxB, plaintext, plaintext_len); 216 DIGESTFinal(B, &ctxB); 217 218 /* 9. - 10. */ 219 for (i = plaintext_len; i > MIXCHARS; i -= MIXCHARS) 220 DIGESTUpdate(&ctxA, B, MIXCHARS); 221 DIGESTUpdate(&ctxA, B, i); 222 223 /* 11. */ 224 for (i = plaintext_len; i > 0; i >>= 1) { 225 if ((i & 1) != 0) { 226 DIGESTUpdate(&ctxA, B, MIXCHARS); 227 } else { 228 DIGESTUpdate(&ctxA, plaintext, plaintext_len); 229 } 230 } 231 232 /* 12. */ 233 DIGESTFinal(A, &ctxA); 234 235 /* 13. - 15. */ 236 DIGESTInit(&ctxDP); 237 for (i = 0; i < plaintext_len; i++) 238 DIGESTUpdate(&ctxDP, plaintext, plaintext_len); 239 DIGESTFinal(DP, &ctxDP); 240 241 /* 16. */ 242 Pp = P = alloca(plaintext_len); 243 for (i = plaintext_len; i >= MIXCHARS; i -= MIXCHARS) { 244 Pp = (char *)(memcpy(Pp, DP, MIXCHARS)) + MIXCHARS; 245 } 246 memcpy(Pp, DP, i); 247 248 /* 17. - 19. */ 249 DIGESTInit(&ctxDS); 250 for (i = 0; i < 16 + (uint8_t)A[0]; i++) 251 DIGESTUpdate(&ctxDS, salt, salt_len); 252 DIGESTFinal(DS, &ctxDS); 253 254 /* 20. */ 255 Sp = S = alloca(salt_len); 256 for (i = salt_len; i >= MIXCHARS; i -= MIXCHARS) { 257 Sp = (char *)(memcpy(Sp, DS, MIXCHARS)) + MIXCHARS; 258 } 259 memcpy(Sp, DS, i); 260 261 /* 21. */ 262 for (i = 0; i < rounds; i++) { 263 DIGESTInit(&ctxC); 264 265 if ((i & 1) != 0) { 266 DIGESTUpdate(&ctxC, P, plaintext_len); 267 } else { 268 if (i == 0) 269 DIGESTUpdate(&ctxC, A, MIXCHARS); 270 else 271 DIGESTUpdate(&ctxC, DP, MIXCHARS); 272 } 273 274 if (i % 3 != 0) { 275 DIGESTUpdate(&ctxC, S, salt_len); 276 } 277 278 if (i % 7 != 0) { 279 DIGESTUpdate(&ctxC, P, plaintext_len); 280 } 281 282 if ((i & 1) != 0) { 283 if (i == 0) 284 DIGESTUpdate(&ctxC, A, MIXCHARS); 285 else 286 DIGESTUpdate(&ctxC, DP, MIXCHARS); 287 } else { 288 DIGESTUpdate(&ctxC, P, plaintext_len); 289 } 290 DIGESTFinal(DP, &ctxC); 291 } 292 293 /* 22. Now make the output string */ 294 if (custom_rounds) { 295 (void) snprintf(ctbuffer, ctbufflen, 296 "%s$rounds=%zu$", crypt_alg_magic, rounds); 297 } else { 298 (void) snprintf(ctbuffer, ctbufflen, 299 "%s$", crypt_alg_magic); 300 } 301 (void) strncat(ctbuffer, (const char *)salt, salt_len); 302 (void) strlcat(ctbuffer, "$", ctbufflen); 303 304 p = ctbuffer + strlen(ctbuffer); 305 ctbufflen -= strlen(ctbuffer); 306 307 #ifdef CRYPT_SHA256 308 b64_from_24bit(DP[ 0], DP[10], DP[20], 4); 309 b64_from_24bit(DP[21], DP[ 1], DP[11], 4); 310 b64_from_24bit(DP[12], DP[22], DP[ 2], 4); 311 b64_from_24bit(DP[ 3], DP[13], DP[23], 4); 312 b64_from_24bit(DP[24], DP[ 4], DP[14], 4); 313 b64_from_24bit(DP[15], DP[25], DP[ 5], 4); 314 b64_from_24bit(DP[ 6], DP[16], DP[26], 4); 315 b64_from_24bit(DP[27], DP[ 7], DP[17], 4); 316 b64_from_24bit(DP[18], DP[28], DP[ 8], 4); 317 b64_from_24bit(DP[ 9], DP[19], DP[29], 4); 318 b64_from_24bit(0, DP[31], DP[30], 3); 319 #elif CRYPT_SHA512 320 b64_from_24bit(DP[ 0], DP[21], DP[42], 4); 321 b64_from_24bit(DP[22], DP[43], DP[ 1], 4); 322 b64_from_24bit(DP[44], DP[ 2], DP[23], 4); 323 b64_from_24bit(DP[ 3], DP[24], DP[45], 4); 324 b64_from_24bit(DP[25], DP[46], DP[ 4], 4); 325 b64_from_24bit(DP[47], DP[ 5], DP[26], 4); 326 b64_from_24bit(DP[ 6], DP[27], DP[48], 4); 327 b64_from_24bit(DP[28], DP[49], DP[ 7], 4); 328 b64_from_24bit(DP[50], DP[ 8], DP[29], 4); 329 b64_from_24bit(DP[ 9], DP[30], DP[51], 4); 330 b64_from_24bit(DP[31], DP[52], DP[10], 4); 331 b64_from_24bit(DP[53], DP[11], DP[32], 4); 332 b64_from_24bit(DP[12], DP[33], DP[54], 4); 333 b64_from_24bit(DP[34], DP[55], DP[13], 4); 334 b64_from_24bit(DP[56], DP[14], DP[35], 4); 335 b64_from_24bit(DP[15], DP[36], DP[57], 4); 336 b64_from_24bit(DP[37], DP[58], DP[16], 4); 337 b64_from_24bit(DP[59], DP[17], DP[38], 4); 338 b64_from_24bit(DP[18], DP[39], DP[60], 4); 339 b64_from_24bit(DP[40], DP[61], DP[19], 4); 340 b64_from_24bit(DP[62], DP[20], DP[41], 4); 341 b64_from_24bit(0, 0, DP[63], 2); 342 #endif 343 *p = '\0'; 344 345 (void) memset(A, 0, sizeof (A)); 346 (void) memset(B, 0, sizeof (B)); 347 (void) memset(DP, 0, sizeof (DP)); 348 (void) memset(DS, 0, sizeof (DS)); 349 350 return (ctbuffer); 351 } 352 353 char * 354 crypt_gensalt_impl(char *gsbuffer, 355 size_t gsbufflen, 356 const char *oldsalt, 357 const struct passwd *userinfo, 358 const char **params) 359 { 360 int fd; 361 int err; 362 ssize_t got; 363 uint64_t rndval; 364 uint32_t confrounds = 0; 365 uint32_t saltrounds; 366 char rndstr[sizeof (rndval) + 1]; 367 int i; 368 369 for (i = 0; params != NULL && params[i] != NULL; i++) { 370 if (strncmp(params[i], ROUNDS, ROUNDSLEN) == 0) { 371 confrounds = getrounds(params[i]); 372 } else { 373 errno = EINVAL; 374 return (NULL); 375 } 376 } 377 378 /* 379 * If the config file has a higher value for rounds= than what 380 * was in the old salt use that, otherwise keep what was in the 381 * old salt. 382 */ 383 saltrounds = getrounds(oldsalt); 384 if (confrounds > saltrounds) { 385 saltrounds = confrounds; 386 } 387 388 if ((fd = open("/dev/urandom", O_RDONLY)) == -1) { 389 return (NULL); 390 } 391 392 got = read(fd, &rndval, sizeof (rndval)); 393 if (got < sizeof (rndval)) { 394 err = errno; 395 (void) close(fd); 396 errno = err; 397 return (NULL); 398 } 399 (void) close(fd); 400 401 to64((char *)&rndstr, rndval, sizeof (rndval)); 402 rndstr[sizeof (rndstr) - 1] = 0; 403 404 if (saltrounds > 0) { 405 if (snprintf(gsbuffer, gsbufflen, 406 "%s$rounds=%d$", 407 crypt_alg_magic, saltrounds) >= gsbufflen) 408 goto fail; 409 } else { 410 if (snprintf(gsbuffer, gsbufflen, 411 "%s$", crypt_alg_magic) >= gsbufflen) 412 goto fail; 413 } 414 if (strlcat(gsbuffer, rndstr, gsbufflen) >= gsbufflen) 415 goto fail; 416 if (strlcat(gsbuffer, "$", gsbufflen) >= gsbufflen) 417 goto fail; 418 419 return (gsbuffer); 420 421 fail: 422 (void) memset(gsbuffer, 0, gsbufflen); 423 return (gsbuffer); 424 } 425