checksum.c

   1 /*
   2  * Routines to support checksumming of bytes.
   3  *
   4  * Copyright (C) 1996 Andrew Tridgell
   5  * Copyright (C) 1996 Paul Mackerras
   6  * Copyright (C) 2004-2022 Wayne Davison
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 3 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * In addition, as a special exception, the copyright holders give
  14  * permission to dynamically link rsync with the OpenSSL and xxhash
  15  * libraries when those libraries are being distributed in compliance
  16  * with their license terms, and to distribute a dynamically linked
  17  * combination of rsync and these libraries.  This is also considered
  18  * to be covered under the GPL's System Libraries exception.
  19  *
  20  * This program is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  * GNU General Public License for more details.
  24  *
  25  * You should have received a copy of the GNU General Public License along
  26  * with this program; if not, visit the http://fsf.org website.
  27  */
  28
  29 #include "rsync.h"
  30
  31 #ifdef SUPPORT_XXHASH
  32 #include <xxhash.h>
  33 # if XXH_VERSION_NUMBER >= 800
  34 #  define SUPPORT_XXH3 1
  35 # endif
  36 #endif
  37
  38 extern int am_server;
  39 extern int whole_file;
  40 extern int checksum_seed;
  41 extern int protocol_version;
  42 extern int proper_seed_order;
  43 extern const char *checksum_choice;
  44
  45 #define NNI_BUILTIN (1<<0)
  46 #define NNI_EVP (1<<1)
  47 #define NNI_EVP_OK (1<<2)
  48
  49 struct name_num_item valid_checksums_items[] = {
  50 #ifdef SUPPORT_XXH3
  51         { CSUM_XXH3_128, 0, "xxh128", NULL },
  52         { CSUM_XXH3_64, 0, "xxh3", NULL },
  53 #endif
  54 #ifdef SUPPORT_XXHASH
  55         { CSUM_XXH64, 0, "xxh64", NULL },
  56         { CSUM_XXH64, 0, "xxhash", NULL },
  57 #endif
  58         { CSUM_MD5, NNI_BUILTIN|NNI_EVP, "md5", NULL },
  59         { CSUM_MD4, NNI_BUILTIN|NNI_EVP, "md4", NULL },
  60 #ifdef SHA_DIGEST_LENGTH
  61         { CSUM_SHA1, NNI_EVP, "sha1", NULL },
  62 #endif
  63 #ifdef SHA256_DIGEST_LENGTH
  64         { CSUM_SHA256, NNI_EVP, "sha256", NULL },
  65 #endif
  66 #ifdef SHA512_DIGEST_LENGTH
  67         { CSUM_SHA512, NNI_EVP, "sha512", NULL },
  68 #endif
  69         { CSUM_NONE, 0, "none", NULL },
  70         { 0, 0, NULL, NULL }
  71 };
  72
  73 struct name_num_obj valid_checksums = {
  74         "checksum", NULL, 0, 0, valid_checksums_items
  75 };
  76
  77 struct name_num_item valid_auth_checksums_items[] = {
  78 #ifdef SHA512_DIGEST_LENGTH
  79         { CSUM_SHA512, NNI_EVP, "sha512", NULL },
  80 #endif
  81 #ifdef SHA256_DIGEST_LENGTH
  82         { CSUM_SHA256, NNI_EVP, "sha256", NULL },
  83 #endif
  84 #ifdef SHA_DIGEST_LENGTH
  85         { CSUM_SHA1, NNI_EVP, "sha1", NULL },
  86 #endif
  87         { CSUM_MD5, NNI_BUILTIN|NNI_EVP, "md5", NULL },
  88         { CSUM_MD4, NNI_BUILTIN|NNI_EVP, "md4", NULL },
  89         { 0, 0, NULL, NULL }
  90 };
  91
  92 struct name_num_obj valid_auth_checksums = {
  93         "daemon auth checksum", NULL, 0, 0, valid_auth_checksums_items
  94 };
  95
  96 /* These cannot make use of openssl, so they're marked just as built-in */
  97 struct name_num_item implied_checksum_md4 =
  98     { CSUM_MD4, NNI_BUILTIN, "md4", NULL };
  99 struct name_num_item implied_checksum_md5 =
 100     { CSUM_MD5, NNI_BUILTIN, "md5", NULL };
 101
 102 struct name_num_item *xfer_sum_nni; /* used for the transfer checksum2 computations */
 103 const EVP_MD *xfer_sum_evp_md;
 104 int xfer_sum_len;
 105 struct name_num_item *file_sum_nni; /* used for the pre-transfer --checksum computations */
 106 const EVP_MD *file_sum_evp_md;
 107 int file_sum_len, file_sum_extra_cnt;
 108
 109 #ifdef USE_OPENSSL
 110 EVP_MD_CTX *ctx_evp = NULL;
 111 #endif
 112 static int initialized_choices = 0;
 113
 114 struct name_num_item *parse_csum_name(const char *name, int len)
 115 {
 116         struct name_num_item *nni;
 117
 118         if (len < 0 && name)
 119                 len = strlen(name);
 120
 121         init_checksum_choices();
 122
 123         if (!name || (len == 4 && strncasecmp(name, "auto", 4) == 0)) {
 124                 if (protocol_version >= 30) {
 125                         if (!proper_seed_order)
 126                                 return &implied_checksum_md5;
 127                         name = "md5";
 128                         len = 3;
 129                 } else {
 130                         if (protocol_version >= 27)
 131                                 implied_checksum_md4.num = CSUM_MD4_OLD;
 132                         else if (protocol_version >= 21)
 133                                 implied_checksum_md4.num = CSUM_MD4_BUSTED;
 134                         else
 135                                 implied_checksum_md4.num = CSUM_MD4_ARCHAIC;
 136                         return &implied_checksum_md4;
 137                 }
 138         }
 139
 140         nni = get_nni_by_name(&valid_checksums, name, len);
 141
 142         if (!nni) {
 143                 rprintf(FERROR, "unknown checksum name: %s\n", name);
 144                 exit_cleanup(RERR_UNSUPPORTED);
 145         }
 146
 147         return nni;
 148 }
 149
 150 static const EVP_MD *csum_evp_md(struct name_num_item *nni)
 151 {
 152 #ifdef USE_OPENSSL
 153         const EVP_MD *emd;
 154         if (!(nni->flags & NNI_EVP))
 155                 return NULL;
 156
 157 #ifdef USE_MD5_ASM
 158         if (nni->num == CSUM_MD5)
 159                 emd = NULL;
 160         else
 161 #endif
 162                 emd = EVP_get_digestbyname(nni->name);
 163         if (emd && !(nni->flags & NNI_EVP_OK)) { /* Make sure it works before we advertise it */
 164                 if (!ctx_evp && !(ctx_evp = EVP_MD_CTX_create()))
 165                         out_of_memory("csum_evp_md");
 166                 /* Some routines are marked as legacy and are not enabled in the openssl.cnf file.
 167                  * If we can't init the emd, we'll fall back to our built-in code. */
 168                 if (EVP_DigestInit_ex(ctx_evp, emd, NULL) == 0)
 169                         emd = NULL;
 170                 else
 171                         nni->flags = (nni->flags & ~NNI_BUILTIN) | NNI_EVP_OK;
 172         }
 173         if (!emd)
 174                 nni->flags &= ~NNI_EVP;
 175         return emd;
 176 #else
 177         return NULL;
 178 #endif
 179 }
 180
 181 void parse_checksum_choice(int final_call)
 182 {
 183         if (valid_checksums.negotiated_nni)
 184                 xfer_sum_nni = file_sum_nni = valid_checksums.negotiated_nni;
 185         else {
 186                 char *cp = checksum_choice ? strchr(checksum_choice, ',') : NULL;
 187                 if (cp) {
 188                         xfer_sum_nni = parse_csum_name(checksum_choice, cp - checksum_choice);
 189                         file_sum_nni = parse_csum_name(cp+1, -1);
 190                 } else
 191                         xfer_sum_nni = file_sum_nni = parse_csum_name(checksum_choice, -1);
 192                 if (am_server && checksum_choice)
 193                         validate_choice_vs_env(NSTR_CHECKSUM, xfer_sum_nni->num, file_sum_nni->num);
 194         }
 195         xfer_sum_len = csum_len_for_type(xfer_sum_nni->num, 0);
 196         file_sum_len = csum_len_for_type(file_sum_nni->num, 0);
 197         xfer_sum_evp_md = csum_evp_md(xfer_sum_nni);
 198         file_sum_evp_md = csum_evp_md(file_sum_nni);
 199
 200         file_sum_extra_cnt = (file_sum_len + EXTRA_LEN - 1) / EXTRA_LEN;
 201
 202         if (xfer_sum_nni->num == CSUM_NONE)
 203                 whole_file = 1;
 204
 205         /* Snag the checksum name for both write_batch's option output & the following debug output. */
 206         if (valid_checksums.negotiated_nni)
 207                 checksum_choice = valid_checksums.negotiated_nni->name;
 208         else if (checksum_choice == NULL)
 209                 checksum_choice = xfer_sum_nni->name;
 210
 211         if (final_call && DEBUG_GTE(NSTR, am_server ? 3 : 1)) {
 212                 rprintf(FINFO, "%s%s checksum: %s\n",
 213                         am_server ? "Server" : "Client",
 214                         valid_checksums.negotiated_nni ? " negotiated" : "",
 215                         checksum_choice);
 216         }
 217 }
 218
 219 int csum_len_for_type(int cst, BOOL flist_csum)
 220 {
 221         switch (cst) {
 222           case CSUM_NONE:
 223                 return 1;
 224           case CSUM_MD4_ARCHAIC:
 225                 /* The oldest checksum code is rather weird: the file-list code only sent
 226                  * 2-byte checksums, but all other checksums were full MD4 length. */
 227                 return flist_csum ? 2 : MD4_DIGEST_LEN;
 228           case CSUM_MD4:
 229           case CSUM_MD4_OLD:
 230           case CSUM_MD4_BUSTED:
 231                 return MD4_DIGEST_LEN;
 232           case CSUM_MD5:
 233                 return MD5_DIGEST_LEN;
 234 #ifdef SHA_DIGEST_LENGTH
 235           case CSUM_SHA1:
 236                 return SHA_DIGEST_LENGTH;
 237 #endif
 238 #ifdef SHA256_DIGEST_LENGTH
 239           case CSUM_SHA256:
 240                 return SHA256_DIGEST_LENGTH;
 241 #endif
 242 #ifdef SHA512_DIGEST_LENGTH
 243           case CSUM_SHA512:
 244                 return SHA512_DIGEST_LENGTH;
 245 #endif
 246           case CSUM_XXH64:
 247           case CSUM_XXH3_64:
 248                 return 64/8;
 249           case CSUM_XXH3_128:
 250                 return 128/8;
 251           default: /* paranoia to prevent missing case values */
 252                 exit_cleanup(RERR_UNSUPPORTED);
 253         }
 254         return 0;
 255 }
 256
 257 /* Returns 0 if the checksum is not canonical (i.e. it includes a seed value).
 258  * Returns 1 if the public sum order matches our internal sum order.
 259  * Returns -1 if the public sum order is the reverse of our internal sum order.
 260  */
 261 int canonical_checksum(int csum_type)
 262 {
 263         switch (csum_type) {
 264           case CSUM_NONE:
 265           case CSUM_MD4_ARCHAIC:
 266           case CSUM_MD4_OLD:
 267           case CSUM_MD4_BUSTED:
 268                 break;
 269           case CSUM_MD4:
 270           case CSUM_MD5:
 271           case CSUM_SHA1:
 272           case CSUM_SHA256:
 273           case CSUM_SHA512:
 274                 return -1;
 275           case CSUM_XXH64:
 276           case CSUM_XXH3_64:
 277           case CSUM_XXH3_128:
 278                 return 1;
 279           default: /* paranoia to prevent missing case values */
 280                 exit_cleanup(RERR_UNSUPPORTED);
 281         }
 282         return 0;
 283 }
 284
 285 #ifndef USE_ROLL_SIMD /* See simd-checksum-*.cpp. */
 286 /*
 287   a simple 32 bit checksum that can be updated from either end
 288   (inspired by Mark Adler's Adler-32 checksum)
 289   */
 290 uint32 get_checksum1(char *buf1, int32 len)
 291 {
 292         int32 i;
 293         uint32 s1, s2;
 294         schar *buf = (schar *)buf1;
 295
 296         s1 = s2 = 0;
 297         for (i = 0; i < (len-4); i+=4) {
 298                 s2 += 4*(s1 + buf[i]) + 3*buf[i+1] + 2*buf[i+2] + buf[i+3] + 10*CHAR_OFFSET;
 299                 s1 += (buf[i+0] + buf[i+1] + buf[i+2] + buf[i+3] + 4*CHAR_OFFSET);
 300         }
 301         for (; i < len; i++) {
 302                 s1 += (buf[i]+CHAR_OFFSET); s2 += s1;
 303         }
 304         return (s1 & 0xffff) + (s2 << 16);
 305 }
 306 #endif
 307
 308 void get_checksum2(char *buf, int32 len, char *sum)
 309 {
 310 #ifdef USE_OPENSSL
 311         if (xfer_sum_evp_md) {
 312                 static EVP_MD_CTX *evp = NULL;
 313                 uchar seedbuf[4];
 314                 if (!evp && !(evp = EVP_MD_CTX_create()))
 315                         out_of_memory("get_checksum2");
 316                 EVP_DigestInit_ex(evp, xfer_sum_evp_md, NULL);
 317                 if (checksum_seed) {
 318                         SIVALu(seedbuf, 0, checksum_seed);
 319                         EVP_DigestUpdate(evp, seedbuf, 4);
 320                 }
 321                 EVP_DigestUpdate(evp, (uchar *)buf, len);
 322                 EVP_DigestFinal_ex(evp, (uchar *)sum, NULL);
 323         } else
 324 #endif
 325         switch (xfer_sum_nni->num) {
 326 #ifdef SUPPORT_XXHASH
 327           case CSUM_XXH64:
 328                 SIVAL64(sum, 0, XXH64(buf, len, checksum_seed));
 329                 break;
 330 #endif
 331 #ifdef SUPPORT_XXH3
 332           case CSUM_XXH3_64:
 333                 SIVAL64(sum, 0, XXH3_64bits_withSeed(buf, len, checksum_seed));
 334                 break;
 335           case CSUM_XXH3_128: {
 336                 XXH128_hash_t digest = XXH3_128bits_withSeed(buf, len, checksum_seed);
 337                 SIVAL64(sum, 0, digest.low64);
 338                 SIVAL64(sum, 8, digest.high64);
 339                 break;
 340           }
 341 #endif
 342           case CSUM_MD5: {
 343                 md_context m5;
 344                 uchar seedbuf[4];
 345                 md5_begin(&m5);
 346                 if (proper_seed_order) {
 347                         if (checksum_seed) {
 348                                 SIVALu(seedbuf, 0, checksum_seed);
 349                                 md5_update(&m5, seedbuf, 4);
 350                         }
 351                         md5_update(&m5, (uchar *)buf, len);
 352                 } else {
 353                         md5_update(&m5, (uchar *)buf, len);
 354                         if (checksum_seed) {
 355                                 SIVALu(seedbuf, 0, checksum_seed);
 356                                 md5_update(&m5, seedbuf, 4);
 357                         }
 358                 }
 359                 md5_result(&m5, (uchar *)sum);
 360                 break;
 361           }
 362           case CSUM_MD4:
 363           case CSUM_MD4_OLD:
 364           case CSUM_MD4_BUSTED:
 365           case CSUM_MD4_ARCHAIC: {
 366                 md_context m;
 367                 int32 i;
 368                 static char *buf1;
 369                 static int32 len1;
 370
 371                 mdfour_begin(&m);
 372
 373                 if (len > len1) {
 374                         if (buf1)
 375                                 free(buf1);
 376                         buf1 = new_array(char, len+4);
 377                         len1 = len;
 378                 }
 379
 380                 memcpy(buf1, buf, len);
 381                 if (checksum_seed) {
 382                         SIVAL(buf1,len,checksum_seed);
 383                         len += 4;
 384                 }
 385
 386                 for (i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK)
 387                         mdfour_update(&m, (uchar *)(buf1+i), CSUM_CHUNK);
 388
 389                 /*
 390                  * Prior to version 27 an incorrect MD4 checksum was computed
 391                  * by failing to call mdfour_tail() for block sizes that
 392                  * are multiples of 64.  This is fixed by calling mdfour_update()
 393                  * even when there are no more bytes.
 394                  */
 395                 if (len - i > 0 || xfer_sum_nni->num > CSUM_MD4_BUSTED)
 396                         mdfour_update(&m, (uchar *)(buf1+i), len-i);
 397
 398                 mdfour_result(&m, (uchar *)sum);
 399                 break;
 400           }
 401           default: /* paranoia to prevent missing case values */
 402                 exit_cleanup(RERR_UNSUPPORTED);
 403         }
 404 }
 405
 406 void file_checksum(const char *fname, const STRUCT_STAT *st_p, char *sum)
 407 {
 408         struct map_struct *buf;
 409         OFF_T i, len = st_p->st_size;
 410         int32 remainder;
 411         int fd;
 412
 413         fd = do_open(fname, O_RDONLY, 0);
 414         if (fd == -1) {
 415                 memset(sum, 0, file_sum_len);
 416                 return;
 417         }
 418
 419         buf = map_file(fd, len, MAX_MAP_SIZE, CHUNK_SIZE);
 420
 421 #ifdef USE_OPENSSL
 422         if (file_sum_evp_md) {
 423                 static EVP_MD_CTX *evp = NULL;
 424                 if (!evp && !(evp = EVP_MD_CTX_create()))
 425                         out_of_memory("file_checksum");
 426
 427                 EVP_DigestInit_ex(evp, file_sum_evp_md, NULL);
 428
 429                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
 430                         EVP_DigestUpdate(evp, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
 431
 432                 remainder = (int32)(len - i);
 433                 if (remainder > 0)
 434                         EVP_DigestUpdate(evp, (uchar *)map_ptr(buf, i, remainder), remainder);
 435
 436                 EVP_DigestFinal_ex(evp, (uchar *)sum, NULL);
 437         } else
 438 #endif
 439         switch (file_sum_nni->num) {
 440 #ifdef SUPPORT_XXHASH
 441           case CSUM_XXH64: {
 442                 static XXH64_state_t* state = NULL;
 443                 if (!state && !(state = XXH64_createState()))
 444                         out_of_memory("file_checksum");
 445
 446                 XXH64_reset(state, 0);
 447
 448                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
 449                         XXH64_update(state, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
 450
 451                 remainder = (int32)(len - i);
 452                 if (remainder > 0)
 453                         XXH64_update(state, (uchar *)map_ptr(buf, i, remainder), remainder);
 454
 455                 SIVAL64(sum, 0, XXH64_digest(state));
 456                 break;
 457           }
 458 #endif
 459 #ifdef SUPPORT_XXH3
 460           case CSUM_XXH3_64: {
 461                 static XXH3_state_t* state = NULL;
 462                 if (!state && !(state = XXH3_createState()))
 463                         out_of_memory("file_checksum");
 464
 465                 XXH3_64bits_reset(state);
 466
 467                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
 468                         XXH3_64bits_update(state, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
 469
 470                 remainder = (int32)(len - i);
 471                 if (remainder > 0)
 472                         XXH3_64bits_update(state, (uchar *)map_ptr(buf, i, remainder), remainder);
 473
 474                 SIVAL64(sum, 0, XXH3_64bits_digest(state));
 475                 break;
 476           }
 477           case CSUM_XXH3_128: {
 478                 XXH128_hash_t digest;
 479                 static XXH3_state_t* state = NULL;
 480                 if (!state && !(state = XXH3_createState()))
 481                         out_of_memory("file_checksum");
 482
 483                 XXH3_128bits_reset(state);
 484
 485                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
 486                         XXH3_128bits_update(state, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
 487
 488                 remainder = (int32)(len - i);
 489                 if (remainder > 0)
 490                         XXH3_128bits_update(state, (uchar *)map_ptr(buf, i, remainder), remainder);
 491
 492                 digest = XXH3_128bits_digest(state);
 493                 SIVAL64(sum, 0, digest.low64);
 494                 SIVAL64(sum, 8, digest.high64);
 495                 break;
 496           }
 497 #endif
 498           case CSUM_MD5: {
 499                 md_context m5;
 500
 501                 md5_begin(&m5);
 502
 503                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
 504                         md5_update(&m5, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
 505
 506                 remainder = (int32)(len - i);
 507                 if (remainder > 0)
 508                         md5_update(&m5, (uchar *)map_ptr(buf, i, remainder), remainder);
 509
 510                 md5_result(&m5, (uchar *)sum);
 511                 break;
 512           }
 513           case CSUM_MD4:
 514           case CSUM_MD4_OLD:
 515           case CSUM_MD4_BUSTED:
 516           case CSUM_MD4_ARCHAIC: {
 517                 md_context m;
 518
 519                 mdfour_begin(&m);
 520
 521                 for (i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK)
 522                         mdfour_update(&m, (uchar *)map_ptr(buf, i, CSUM_CHUNK), CSUM_CHUNK);
 523
 524                 /* Prior to version 27 an incorrect MD4 checksum was computed
 525                  * by failing to call mdfour_tail() for block sizes that
 526                  * are multiples of 64.  This is fixed by calling mdfour_update()
 527                  * even when there are no more bytes. */
 528                 remainder = (int32)(len - i);
 529                 if (remainder > 0 || file_sum_nni->num > CSUM_MD4_BUSTED)
 530                         mdfour_update(&m, (uchar *)map_ptr(buf, i, remainder), remainder);
 531
 532                 mdfour_result(&m, (uchar *)sum);
 533                 break;
 534           }
 535           default:
 536                 rprintf(FERROR, "Invalid checksum-choice for --checksum: %s (%d)\n",
 537                         file_sum_nni->name, file_sum_nni->num);
 538                 exit_cleanup(RERR_UNSUPPORTED);
 539         }
 540
 541         close(fd);
 542         unmap_file(buf);
 543 }
 544
 545 static int32 sumresidue;
 546 static md_context ctx_md;
 547 #ifdef SUPPORT_XXHASH
 548 static XXH64_state_t* xxh64_state;
 549 #endif
 550 #ifdef SUPPORT_XXH3
 551 static XXH3_state_t* xxh3_state;
 552 #endif
 553 static struct name_num_item *cur_sum_nni;
 554 static const EVP_MD *cur_sum_evp_md;
 555 int cur_sum_len;
 556
 557 int sum_init(struct name_num_item *nni, int seed)
 558 {
 559         char s[4];
 560
 561         if (!nni)
 562                 nni = parse_csum_name(NULL, 0);
 563         cur_sum_nni = nni;
 564         cur_sum_len = csum_len_for_type(nni->num, 0);
 565         cur_sum_evp_md = csum_evp_md(nni);
 566
 567 #ifdef USE_OPENSSL
 568         if (cur_sum_evp_md) {
 569                 if (!ctx_evp && !(ctx_evp = EVP_MD_CTX_create()))
 570                         out_of_memory("file_checksum");
 571                 EVP_DigestInit_ex(ctx_evp, cur_sum_evp_md, NULL);
 572         } else
 573 #endif
 574         switch (cur_sum_nni->num) {
 575 #ifdef SUPPORT_XXHASH
 576           case CSUM_XXH64:
 577                 if (!xxh64_state && !(xxh64_state = XXH64_createState()))
 578                         out_of_memory("sum_init");
 579                 XXH64_reset(xxh64_state, 0);
 580                 break;
 581 #endif
 582 #ifdef SUPPORT_XXH3
 583           case CSUM_XXH3_64:
 584                 if (!xxh3_state && !(xxh3_state = XXH3_createState()))
 585                         out_of_memory("sum_init");
 586                 XXH3_64bits_reset(xxh3_state);
 587                 break;
 588           case CSUM_XXH3_128:
 589                 if (!xxh3_state && !(xxh3_state = XXH3_createState()))
 590                         out_of_memory("sum_init");
 591                 XXH3_128bits_reset(xxh3_state);
 592                 break;
 593 #endif
 594           case CSUM_MD5:
 595                 md5_begin(&ctx_md);
 596                 break;
 597           case CSUM_MD4:
 598                 mdfour_begin(&ctx_md);
 599                 sumresidue = 0;
 600                 break;
 601           case CSUM_MD4_OLD:
 602           case CSUM_MD4_BUSTED:
 603           case CSUM_MD4_ARCHAIC:
 604                 mdfour_begin(&ctx_md);
 605                 sumresidue = 0;
 606                 SIVAL(s, 0, seed);
 607                 sum_update(s, 4);
 608                 break;
 609           case CSUM_NONE:
 610                 break;
 611           default: /* paranoia to prevent missing case values */
 612                 exit_cleanup(RERR_UNSUPPORTED);
 613         }
 614
 615         return cur_sum_len;
 616 }
 617
 618 /**
 619  * Feed data into an MD4 accumulator, md.  The results may be
 620  * retrieved using sum_end().  md is used for different purposes at
 621  * different points during execution.
 622  *
 623  * @todo Perhaps get rid of md and just pass in the address each time.
 624  * Very slightly clearer and slower.
 625  **/
 626 void sum_update(const char *p, int32 len)
 627 {
 628 #ifdef USE_OPENSSL
 629         if (cur_sum_evp_md) {
 630                 EVP_DigestUpdate(ctx_evp, (uchar *)p, len);
 631         } else
 632 #endif
 633         switch (cur_sum_nni->num) {
 634 #ifdef SUPPORT_XXHASH
 635           case CSUM_XXH64:
 636                 XXH64_update(xxh64_state, p, len);
 637                 break;
 638 #endif
 639 #ifdef SUPPORT_XXH3
 640           case CSUM_XXH3_64:
 641                 XXH3_64bits_update(xxh3_state, p, len);
 642                 break;
 643           case CSUM_XXH3_128:
 644                 XXH3_128bits_update(xxh3_state, p, len);
 645                 break;
 646 #endif
 647           case CSUM_MD5:
 648                 md5_update(&ctx_md, (uchar *)p, len);
 649                 break;
 650           case CSUM_MD4:
 651           case CSUM_MD4_OLD:
 652           case CSUM_MD4_BUSTED:
 653           case CSUM_MD4_ARCHAIC:
 654                 if (len + sumresidue < CSUM_CHUNK) {
 655                         memcpy(ctx_md.buffer + sumresidue, p, len);
 656                         sumresidue += len;
 657                         break;
 658                 }
 659
 660                 if (sumresidue) {
 661                         int32 i = CSUM_CHUNK - sumresidue;
 662                         memcpy(ctx_md.buffer + sumresidue, p, i);
 663                         mdfour_update(&ctx_md, (uchar *)ctx_md.buffer, CSUM_CHUNK);
 664                         len -= i;
 665                         p += i;
 666                 }
 667
 668                 while (len >= CSUM_CHUNK) {
 669                         mdfour_update(&ctx_md, (uchar *)p, CSUM_CHUNK);
 670                         len -= CSUM_CHUNK;
 671                         p += CSUM_CHUNK;
 672                 }
 673
 674                 sumresidue = len;
 675                 if (sumresidue)
 676                         memcpy(ctx_md.buffer, p, sumresidue);
 677                 break;
 678           case CSUM_NONE:
 679                 break;
 680           default: /* paranoia to prevent missing case values */
 681                 exit_cleanup(RERR_UNSUPPORTED);
 682         }
 683 }
 684
 685 /* The sum buffer only needs to be as long as the current checksum's digest
 686  * len, not MAX_DIGEST_LEN. Note that for CSUM_MD4_ARCHAIC that is the full
 687  * MD4_DIGEST_LEN even if the file-list code is going to ignore all but the
 688  * first 2 bytes of it. */
 689 void sum_end(char *sum)
 690 {
 691 #ifdef USE_OPENSSL
 692         if (cur_sum_evp_md) {
 693                 EVP_DigestFinal_ex(ctx_evp, (uchar *)sum, NULL);
 694         } else
 695 #endif
 696         switch (cur_sum_nni->num) {
 697 #ifdef SUPPORT_XXHASH
 698           case CSUM_XXH64:
 699                 SIVAL64(sum, 0, XXH64_digest(xxh64_state));
 700                 break;
 701 #endif
 702 #ifdef SUPPORT_XXH3
 703           case CSUM_XXH3_64:
 704                 SIVAL64(sum, 0, XXH3_64bits_digest(xxh3_state));
 705                 break;
 706           case CSUM_XXH3_128: {
 707                 XXH128_hash_t digest = XXH3_128bits_digest(xxh3_state);
 708                 SIVAL64(sum, 0, digest.low64);
 709                 SIVAL64(sum, 8, digest.high64);
 710                 break;
 711           }
 712 #endif
 713           case CSUM_MD5:
 714                 md5_result(&ctx_md, (uchar *)sum);
 715                 break;
 716           case CSUM_MD4:
 717           case CSUM_MD4_OLD:
 718                 mdfour_update(&ctx_md, (uchar *)ctx_md.buffer, sumresidue);
 719                 mdfour_result(&ctx_md, (uchar *)sum);
 720                 break;
 721           case CSUM_MD4_BUSTED:
 722           case CSUM_MD4_ARCHAIC:
 723                 if (sumresidue)
 724                         mdfour_update(&ctx_md, (uchar *)ctx_md.buffer, sumresidue);
 725                 mdfour_result(&ctx_md, (uchar *)sum);
 726                 break;
 727           case CSUM_NONE:
 728                 *sum = '\0';
 729                 break;
 730           default: /* paranoia to prevent missing case values */
 731                 exit_cleanup(RERR_UNSUPPORTED);
 732         }
 733 }
 734
 735 #if defined SUPPORT_XXH3 || defined USE_OPENSSL
 736 static void verify_digest(struct name_num_item *nni, BOOL check_auth_list)
 737 {
 738 #ifdef SUPPORT_XXH3
 739         static int xxh3_result = 0;
 740 #endif
 741 #ifdef USE_OPENSSL
 742         static int prior_num = 0, prior_flags = 0, prior_result = 0;
 743 #endif
 744
 745 #ifdef SUPPORT_XXH3
 746         if (nni->num == CSUM_XXH3_64 || nni->num == CSUM_XXH3_128) {
 747                 if (!xxh3_result) {
 748                         char buf[32816];
 749                         int j;
 750                         for (j = 0; j < (int)sizeof buf; j++)
 751                                 buf[j] = ' ' + (j % 96);
 752                         sum_init(nni, 0);
 753                         sum_update(buf, 32816);
 754                         sum_update(buf, 31152);
 755                         sum_update(buf, 32474);
 756                         sum_update(buf, 9322);
 757                         xxh3_result = XXH3_64bits_digest(xxh3_state) != 0xadbcf16d4678d1de ? -1 : 1;
 758                 }
 759                 if (xxh3_result < 0)
 760                         nni->num = CSUM_gone;
 761                 return;
 762         }
 763 #endif
 764
 765 #ifdef USE_OPENSSL
 766         if (BITS_SETnUNSET(nni->flags, NNI_EVP, NNI_BUILTIN|NNI_EVP_OK)) {
 767                 if (nni->num == prior_num && nni->flags == prior_flags) {
 768                         nni->flags = prior_result;
 769                         if (!(nni->flags & NNI_EVP))
 770                                 nni->num = CSUM_gone;
 771                 } else {
 772                         prior_num = nni->num;
 773                         prior_flags = nni->flags;
 774                         if (!csum_evp_md(nni))
 775                                 nni->num = CSUM_gone;
 776                         prior_result = nni->flags;
 777                         if (check_auth_list && (nni = get_nni_by_num(&valid_auth_checksums, prior_num)) != NULL)
 778                                 verify_digest(nni, False);
 779                 }
 780         }
 781 #endif
 782 }
 783 #endif
 784
 785 void init_checksum_choices()
 786 {
 787         struct name_num_item *nni;
 788
 789         if (initialized_choices)
 790                 return;
 791
 792 #if defined SUPPORT_XXH3 || defined USE_OPENSSL
 793         for (nni = valid_checksums.list; nni->name; nni++)
 794                 verify_digest(nni, True);
 795
 796         for (nni = valid_auth_checksums.list; nni->name; nni++)
 797                 verify_digest(nni, False);
 798 #endif
 799
 800         initialized_choices = 1;
 801 }