Tweak shell protection news to mention a few more characters.
[rsync.git] / 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         { CSUM_NONE, 0, "none", NULL },
64         { 0, 0, NULL, NULL }
65 };
66
67 struct name_num_obj valid_checksums = {
68         "checksum", NULL, 0, 0, valid_checksums_items
69 };
70
71 struct name_num_item valid_auth_checksums_items[] = {
72 #ifdef SHA512_DIGEST_LENGTH
73         { CSUM_SHA512, NNI_EVP, "sha512", NULL },
74 #endif
75 #ifdef SHA256_DIGEST_LENGTH
76         { CSUM_SHA256, NNI_EVP, "sha256", NULL },
77 #endif
78 #ifdef SHA_DIGEST_LENGTH
79         { CSUM_SHA1, NNI_EVP, "sha1", NULL },
80 #endif
81         { CSUM_MD5, NNI_BUILTIN|NNI_EVP, "md5", NULL },
82         { CSUM_MD4, NNI_BUILTIN|NNI_EVP, "md4", NULL },
83         { 0, 0, NULL, NULL }
84 };
85
86 struct name_num_obj valid_auth_checksums = {
87         "daemon auth checksum", NULL, 0, 0, valid_auth_checksums_items
88 };
89
90 /* These cannot make use of openssl, so they're marked just as built-in */
91 struct name_num_item implied_checksum_md4 =
92     { CSUM_MD4, NNI_BUILTIN, "md4", NULL };
93 struct name_num_item implied_checksum_md5 =
94     { CSUM_MD5, NNI_BUILTIN, "md5", NULL };
95
96 struct name_num_item *xfer_sum_nni; /* used for the transfer checksum2 computations */
97 int xfer_sum_len;
98 struct name_num_item *file_sum_nni; /* used for the pre-transfer --checksum computations */
99 int file_sum_len, file_sum_extra_cnt;
100
101 #ifdef USE_OPENSSL
102 const EVP_MD *xfer_sum_evp_md;
103 const EVP_MD *file_sum_evp_md;
104 EVP_MD_CTX *ctx_evp = NULL;
105 #endif
106
107 static int initialized_choices = 0;
108
109 struct name_num_item *parse_csum_name(const char *name, int len)
110 {
111         struct name_num_item *nni;
112
113         if (len < 0 && name)
114                 len = strlen(name);
115
116         init_checksum_choices();
117
118         if (!name || (len == 4 && strncasecmp(name, "auto", 4) == 0)) {
119                 if (protocol_version >= 30) {
120                         if (!proper_seed_order)
121                                 return &implied_checksum_md5;
122                         name = "md5";
123                         len = 3;
124                 } else {
125                         if (protocol_version >= 27)
126                                 implied_checksum_md4.num = CSUM_MD4_OLD;
127                         else if (protocol_version >= 21)
128                                 implied_checksum_md4.num = CSUM_MD4_BUSTED;
129                         else
130                                 implied_checksum_md4.num = CSUM_MD4_ARCHAIC;
131                         return &implied_checksum_md4;
132                 }
133         }
134
135         nni = get_nni_by_name(&valid_checksums, name, len);
136
137         if (!nni) {
138                 rprintf(FERROR, "unknown checksum name: %s\n", name);
139                 exit_cleanup(RERR_UNSUPPORTED);
140         }
141
142         return nni;
143 }
144
145 #ifdef USE_OPENSSL
146 static const EVP_MD *csum_evp_md(struct name_num_item *nni)
147 {
148         const EVP_MD *emd;
149         if (!(nni->flags & NNI_EVP))
150                 return NULL;
151
152 #ifdef USE_MD5_ASM
153         if (nni->num == CSUM_MD5)
154                 emd = NULL;
155         else
156 #endif
157                 emd = EVP_get_digestbyname(nni->name);
158         if (emd && !(nni->flags & NNI_EVP_OK)) { /* Make sure it works before we advertise it */
159                 if (!ctx_evp && !(ctx_evp = EVP_MD_CTX_create()))
160                         out_of_memory("csum_evp_md");
161                 /* Some routines are marked as legacy and are not enabled in the openssl.cnf file.
162                  * If we can't init the emd, we'll fall back to our built-in code. */
163                 if (EVP_DigestInit_ex(ctx_evp, emd, NULL) == 0)
164                         emd = NULL;
165                 else
166                         nni->flags = (nni->flags & ~NNI_BUILTIN) | NNI_EVP_OK;
167         }
168         if (!emd)
169                 nni->flags &= ~NNI_EVP;
170         return emd;
171 }
172 #endif
173
174 void parse_checksum_choice(int final_call)
175 {
176         if (valid_checksums.negotiated_nni)
177                 xfer_sum_nni = file_sum_nni = valid_checksums.negotiated_nni;
178         else {
179                 char *cp = checksum_choice ? strchr(checksum_choice, ',') : NULL;
180                 if (cp) {
181                         xfer_sum_nni = parse_csum_name(checksum_choice, cp - checksum_choice);
182                         file_sum_nni = parse_csum_name(cp+1, -1);
183                 } else
184                         xfer_sum_nni = file_sum_nni = parse_csum_name(checksum_choice, -1);
185                 if (am_server && checksum_choice)
186                         validate_choice_vs_env(NSTR_CHECKSUM, xfer_sum_nni->num, file_sum_nni->num);
187         }
188         xfer_sum_len = csum_len_for_type(xfer_sum_nni->num, 0);
189         file_sum_len = csum_len_for_type(file_sum_nni->num, 0);
190 #ifdef USE_OPENSSL
191         xfer_sum_evp_md = csum_evp_md(xfer_sum_nni);
192         file_sum_evp_md = csum_evp_md(file_sum_nni);
193 #endif
194
195         file_sum_extra_cnt = (file_sum_len + EXTRA_LEN - 1) / EXTRA_LEN;
196
197         if (xfer_sum_nni->num == CSUM_NONE)
198                 whole_file = 1;
199
200         /* Snag the checksum name for both write_batch's option output & the following debug output. */
201         if (valid_checksums.negotiated_nni)
202                 checksum_choice = valid_checksums.negotiated_nni->name;
203         else if (checksum_choice == NULL)
204                 checksum_choice = xfer_sum_nni->name;
205
206         if (final_call && DEBUG_GTE(NSTR, am_server ? 3 : 1)) {
207                 rprintf(FINFO, "%s%s checksum: %s\n",
208                         am_server ? "Server" : "Client",
209                         valid_checksums.negotiated_nni ? " negotiated" : "",
210                         checksum_choice);
211         }
212 }
213
214 int csum_len_for_type(int cst, BOOL flist_csum)
215 {
216         switch (cst) {
217           case CSUM_NONE:
218                 return 1;
219           case CSUM_MD4_ARCHAIC:
220                 /* The oldest checksum code is rather weird: the file-list code only sent
221                  * 2-byte checksums, but all other checksums were full MD4 length. */
222                 return flist_csum ? 2 : MD4_DIGEST_LEN;
223           case CSUM_MD4:
224           case CSUM_MD4_OLD:
225           case CSUM_MD4_BUSTED:
226                 return MD4_DIGEST_LEN;
227           case CSUM_MD5:
228                 return MD5_DIGEST_LEN;
229 #ifdef SHA_DIGEST_LENGTH
230           case CSUM_SHA1:
231                 return SHA_DIGEST_LENGTH;
232 #endif
233 #ifdef SHA256_DIGEST_LENGTH
234           case CSUM_SHA256:
235                 return SHA256_DIGEST_LENGTH;
236 #endif
237 #ifdef SHA512_DIGEST_LENGTH
238           case CSUM_SHA512:
239                 return SHA512_DIGEST_LENGTH;
240 #endif
241           case CSUM_XXH64:
242           case CSUM_XXH3_64:
243                 return 64/8;
244           case CSUM_XXH3_128:
245                 return 128/8;
246           default: /* paranoia to prevent missing case values */
247                 exit_cleanup(RERR_UNSUPPORTED);
248         }
249         return 0;
250 }
251
252 /* Returns 0 if the checksum is not canonical (i.e. it includes a seed value).
253  * Returns 1 if the public sum order matches our internal sum order.
254  * Returns -1 if the public sum order is the reverse of our internal sum order.
255  */
256 int canonical_checksum(int csum_type)
257 {
258         switch (csum_type) {
259           case CSUM_NONE:
260           case CSUM_MD4_ARCHAIC:
261           case CSUM_MD4_OLD:
262           case CSUM_MD4_BUSTED:
263                 break;
264           case CSUM_MD4:
265           case CSUM_MD5:
266           case CSUM_SHA1:
267           case CSUM_SHA256:
268           case CSUM_SHA512:
269                 return -1;
270           case CSUM_XXH64:
271           case CSUM_XXH3_64:
272           case CSUM_XXH3_128:
273                 return 1;
274           default: /* paranoia to prevent missing case values */
275                 exit_cleanup(RERR_UNSUPPORTED);
276         }
277         return 0;
278 }
279
280 #ifndef USE_ROLL_SIMD /* See simd-checksum-*.cpp. */
281 /*
282   a simple 32 bit checksum that can be updated from either end
283   (inspired by Mark Adler's Adler-32 checksum)
284   */
285 uint32 get_checksum1(char *buf1, int32 len)
286 {
287         int32 i;
288         uint32 s1, s2;
289         schar *buf = (schar *)buf1;
290
291         s1 = s2 = 0;
292         for (i = 0; i < (len-4); i+=4) {
293                 s2 += 4*(s1 + buf[i]) + 3*buf[i+1] + 2*buf[i+2] + buf[i+3] + 10*CHAR_OFFSET;
294                 s1 += (buf[i+0] + buf[i+1] + buf[i+2] + buf[i+3] + 4*CHAR_OFFSET);
295         }
296         for (; i < len; i++) {
297                 s1 += (buf[i]+CHAR_OFFSET); s2 += s1;
298         }
299         return (s1 & 0xffff) + (s2 << 16);
300 }
301 #endif
302
303 void get_checksum2(char *buf, int32 len, char *sum)
304 {
305 #ifdef USE_OPENSSL
306         if (xfer_sum_evp_md) {
307                 static EVP_MD_CTX *evp = NULL;
308                 uchar seedbuf[4];
309                 if (!evp && !(evp = EVP_MD_CTX_create()))
310                         out_of_memory("get_checksum2");
311                 EVP_DigestInit_ex(evp, xfer_sum_evp_md, NULL);
312                 if (checksum_seed) {
313                         SIVALu(seedbuf, 0, checksum_seed);
314                         EVP_DigestUpdate(evp, seedbuf, 4);
315                 }
316                 EVP_DigestUpdate(evp, (uchar *)buf, len);
317                 EVP_DigestFinal_ex(evp, (uchar *)sum, NULL);
318         } else
319 #endif
320         switch (xfer_sum_nni->num) {
321 #ifdef SUPPORT_XXHASH
322           case CSUM_XXH64:
323                 SIVAL64(sum, 0, XXH64(buf, len, checksum_seed));
324                 break;
325 #endif
326 #ifdef SUPPORT_XXH3
327           case CSUM_XXH3_64:
328                 SIVAL64(sum, 0, XXH3_64bits_withSeed(buf, len, checksum_seed));
329                 break;
330           case CSUM_XXH3_128: {
331                 XXH128_hash_t digest = XXH3_128bits_withSeed(buf, len, checksum_seed);
332                 SIVAL64(sum, 0, digest.low64);
333                 SIVAL64(sum, 8, digest.high64);
334                 break;
335           }
336 #endif
337           case CSUM_MD5: {
338                 md_context m5;
339                 uchar seedbuf[4];
340                 md5_begin(&m5);
341                 if (proper_seed_order) {
342                         if (checksum_seed) {
343                                 SIVALu(seedbuf, 0, checksum_seed);
344                                 md5_update(&m5, seedbuf, 4);
345                         }
346                         md5_update(&m5, (uchar *)buf, len);
347                 } else {
348                         md5_update(&m5, (uchar *)buf, len);
349                         if (checksum_seed) {
350                                 SIVALu(seedbuf, 0, checksum_seed);
351                                 md5_update(&m5, seedbuf, 4);
352                         }
353                 }
354                 md5_result(&m5, (uchar *)sum);
355                 break;
356           }
357           case CSUM_MD4:
358           case CSUM_MD4_OLD:
359           case CSUM_MD4_BUSTED:
360           case CSUM_MD4_ARCHAIC: {
361                 md_context m;
362                 int32 i;
363                 static char *buf1;
364                 static int32 len1;
365
366                 mdfour_begin(&m);
367
368                 if (len > len1) {
369                         if (buf1)
370                                 free(buf1);
371                         buf1 = new_array(char, len+4);
372                         len1 = len;
373                 }
374
375                 memcpy(buf1, buf, len);
376                 if (checksum_seed) {
377                         SIVAL(buf1,len,checksum_seed);
378                         len += 4;
379                 }
380
381                 for (i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK)
382                         mdfour_update(&m, (uchar *)(buf1+i), CSUM_CHUNK);
383
384                 /*
385                  * Prior to version 27 an incorrect MD4 checksum was computed
386                  * by failing to call mdfour_tail() for block sizes that
387                  * are multiples of 64.  This is fixed by calling mdfour_update()
388                  * even when there are no more bytes.
389                  */
390                 if (len - i > 0 || xfer_sum_nni->num > CSUM_MD4_BUSTED)
391                         mdfour_update(&m, (uchar *)(buf1+i), len-i);
392
393                 mdfour_result(&m, (uchar *)sum);
394                 break;
395           }
396           default: /* paranoia to prevent missing case values */
397                 exit_cleanup(RERR_UNSUPPORTED);
398         }
399 }
400
401 void file_checksum(const char *fname, const STRUCT_STAT *st_p, char *sum)
402 {
403         struct map_struct *buf;
404         OFF_T i, len = st_p->st_size;
405         int32 remainder;
406         int fd;
407
408         fd = do_open(fname, O_RDONLY, 0);
409         if (fd == -1) {
410                 memset(sum, 0, file_sum_len);
411                 return;
412         }
413
414         buf = map_file(fd, len, MAX_MAP_SIZE, CHUNK_SIZE);
415
416 #ifdef USE_OPENSSL
417         if (file_sum_evp_md) {
418                 static EVP_MD_CTX *evp = NULL;
419                 if (!evp && !(evp = EVP_MD_CTX_create()))
420                         out_of_memory("file_checksum");
421
422                 EVP_DigestInit_ex(evp, file_sum_evp_md, NULL);
423
424                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
425                         EVP_DigestUpdate(evp, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
426
427                 remainder = (int32)(len - i);
428                 if (remainder > 0)
429                         EVP_DigestUpdate(evp, (uchar *)map_ptr(buf, i, remainder), remainder);
430
431                 EVP_DigestFinal_ex(evp, (uchar *)sum, NULL);
432         } else
433 #endif
434         switch (file_sum_nni->num) {
435 #ifdef SUPPORT_XXHASH
436           case CSUM_XXH64: {
437                 static XXH64_state_t* state = NULL;
438                 if (!state && !(state = XXH64_createState()))
439                         out_of_memory("file_checksum");
440
441                 XXH64_reset(state, 0);
442
443                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
444                         XXH64_update(state, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
445
446                 remainder = (int32)(len - i);
447                 if (remainder > 0)
448                         XXH64_update(state, (uchar *)map_ptr(buf, i, remainder), remainder);
449
450                 SIVAL64(sum, 0, XXH64_digest(state));
451                 break;
452           }
453 #endif
454 #ifdef SUPPORT_XXH3
455           case CSUM_XXH3_64: {
456                 static XXH3_state_t* state = NULL;
457                 if (!state && !(state = XXH3_createState()))
458                         out_of_memory("file_checksum");
459
460                 XXH3_64bits_reset(state);
461
462                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
463                         XXH3_64bits_update(state, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
464
465                 remainder = (int32)(len - i);
466                 if (remainder > 0)
467                         XXH3_64bits_update(state, (uchar *)map_ptr(buf, i, remainder), remainder);
468
469                 SIVAL64(sum, 0, XXH3_64bits_digest(state));
470                 break;
471           }
472           case CSUM_XXH3_128: {
473                 XXH128_hash_t digest;
474                 static XXH3_state_t* state = NULL;
475                 if (!state && !(state = XXH3_createState()))
476                         out_of_memory("file_checksum");
477
478                 XXH3_128bits_reset(state);
479
480                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
481                         XXH3_128bits_update(state, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
482
483                 remainder = (int32)(len - i);
484                 if (remainder > 0)
485                         XXH3_128bits_update(state, (uchar *)map_ptr(buf, i, remainder), remainder);
486
487                 digest = XXH3_128bits_digest(state);
488                 SIVAL64(sum, 0, digest.low64);
489                 SIVAL64(sum, 8, digest.high64);
490                 break;
491           }
492 #endif
493           case CSUM_MD5: {
494                 md_context m5;
495
496                 md5_begin(&m5);
497
498                 for (i = 0; i + CHUNK_SIZE <= len; i += CHUNK_SIZE)
499                         md5_update(&m5, (uchar *)map_ptr(buf, i, CHUNK_SIZE), CHUNK_SIZE);
500
501                 remainder = (int32)(len - i);
502                 if (remainder > 0)
503                         md5_update(&m5, (uchar *)map_ptr(buf, i, remainder), remainder);
504
505                 md5_result(&m5, (uchar *)sum);
506                 break;
507           }
508           case CSUM_MD4:
509           case CSUM_MD4_OLD:
510           case CSUM_MD4_BUSTED:
511           case CSUM_MD4_ARCHAIC: {
512                 md_context m;
513
514                 mdfour_begin(&m);
515
516                 for (i = 0; i + CSUM_CHUNK <= len; i += CSUM_CHUNK)
517                         mdfour_update(&m, (uchar *)map_ptr(buf, i, CSUM_CHUNK), CSUM_CHUNK);
518
519                 /* Prior to version 27 an incorrect MD4 checksum was computed
520                  * by failing to call mdfour_tail() for block sizes that
521                  * are multiples of 64.  This is fixed by calling mdfour_update()
522                  * even when there are no more bytes. */
523                 remainder = (int32)(len - i);
524                 if (remainder > 0 || file_sum_nni->num > CSUM_MD4_BUSTED)
525                         mdfour_update(&m, (uchar *)map_ptr(buf, i, remainder), remainder);
526
527                 mdfour_result(&m, (uchar *)sum);
528                 break;
529           }
530           default:
531                 rprintf(FERROR, "Invalid checksum-choice for --checksum: %s (%d)\n",
532                         file_sum_nni->name, file_sum_nni->num);
533                 exit_cleanup(RERR_UNSUPPORTED);
534         }
535
536         close(fd);
537         unmap_file(buf);
538 }
539
540 static int32 sumresidue;
541 static md_context ctx_md;
542 #ifdef SUPPORT_XXHASH
543 static XXH64_state_t* xxh64_state;
544 #endif
545 #ifdef SUPPORT_XXH3
546 static XXH3_state_t* xxh3_state;
547 #endif
548 static struct name_num_item *cur_sum_nni;
549 int cur_sum_len;
550
551 #ifdef USE_OPENSSL
552 static const EVP_MD *cur_sum_evp_md;
553 #endif
554
555 /* Initialize a hash digest accumulator.  Data is supplied via
556  * sum_update() and the resulting binary digest is retrieved via
557  * sum_end().  This only supports one active sum at a time. */
558 int sum_init(struct name_num_item *nni, int seed)
559 {
560         char s[4];
561
562         if (!nni)
563                 nni = parse_csum_name(NULL, 0);
564         cur_sum_nni = nni;
565         cur_sum_len = csum_len_for_type(nni->num, 0);
566 #ifdef USE_OPENSSL
567         cur_sum_evp_md = csum_evp_md(nni);
568 #endif
569
570 #ifdef USE_OPENSSL
571         if (cur_sum_evp_md) {
572                 if (!ctx_evp && !(ctx_evp = EVP_MD_CTX_create()))
573                         out_of_memory("file_checksum");
574                 EVP_DigestInit_ex(ctx_evp, cur_sum_evp_md, NULL);
575         } else
576 #endif
577         switch (cur_sum_nni->num) {
578 #ifdef SUPPORT_XXHASH
579           case CSUM_XXH64:
580                 if (!xxh64_state && !(xxh64_state = XXH64_createState()))
581                         out_of_memory("sum_init");
582                 XXH64_reset(xxh64_state, 0);
583                 break;
584 #endif
585 #ifdef SUPPORT_XXH3
586           case CSUM_XXH3_64:
587                 if (!xxh3_state && !(xxh3_state = XXH3_createState()))
588                         out_of_memory("sum_init");
589                 XXH3_64bits_reset(xxh3_state);
590                 break;
591           case CSUM_XXH3_128:
592                 if (!xxh3_state && !(xxh3_state = XXH3_createState()))
593                         out_of_memory("sum_init");
594                 XXH3_128bits_reset(xxh3_state);
595                 break;
596 #endif
597           case CSUM_MD5:
598                 md5_begin(&ctx_md);
599                 break;
600           case CSUM_MD4:
601                 mdfour_begin(&ctx_md);
602                 sumresidue = 0;
603                 break;
604           case CSUM_MD4_OLD:
605           case CSUM_MD4_BUSTED:
606           case CSUM_MD4_ARCHAIC:
607                 mdfour_begin(&ctx_md);
608                 sumresidue = 0;
609                 SIVAL(s, 0, seed);
610                 sum_update(s, 4);
611                 break;
612           case CSUM_NONE:
613                 break;
614           default: /* paranoia to prevent missing case values */
615                 exit_cleanup(RERR_UNSUPPORTED);
616         }
617
618         return cur_sum_len;
619 }
620
621 /* Feed data into a hash digest accumulator. */
622 void sum_update(const char *p, int32 len)
623 {
624 #ifdef USE_OPENSSL
625         if (cur_sum_evp_md) {
626                 EVP_DigestUpdate(ctx_evp, (uchar *)p, len);
627         } else
628 #endif
629         switch (cur_sum_nni->num) {
630 #ifdef SUPPORT_XXHASH
631           case CSUM_XXH64:
632                 XXH64_update(xxh64_state, p, len);
633                 break;
634 #endif
635 #ifdef SUPPORT_XXH3
636           case CSUM_XXH3_64:
637                 XXH3_64bits_update(xxh3_state, p, len);
638                 break;
639           case CSUM_XXH3_128:
640                 XXH3_128bits_update(xxh3_state, p, len);
641                 break;
642 #endif
643           case CSUM_MD5:
644                 md5_update(&ctx_md, (uchar *)p, len);
645                 break;
646           case CSUM_MD4:
647           case CSUM_MD4_OLD:
648           case CSUM_MD4_BUSTED:
649           case CSUM_MD4_ARCHAIC:
650                 if (len + sumresidue < CSUM_CHUNK) {
651                         memcpy(ctx_md.buffer + sumresidue, p, len);
652                         sumresidue += len;
653                         break;
654                 }
655
656                 if (sumresidue) {
657                         int32 i = CSUM_CHUNK - sumresidue;
658                         memcpy(ctx_md.buffer + sumresidue, p, i);
659                         mdfour_update(&ctx_md, (uchar *)ctx_md.buffer, CSUM_CHUNK);
660                         len -= i;
661                         p += i;
662                 }
663
664                 while (len >= CSUM_CHUNK) {
665                         mdfour_update(&ctx_md, (uchar *)p, CSUM_CHUNK);
666                         len -= CSUM_CHUNK;
667                         p += CSUM_CHUNK;
668                 }
669
670                 sumresidue = len;
671                 if (sumresidue)
672                         memcpy(ctx_md.buffer, p, sumresidue);
673                 break;
674           case CSUM_NONE:
675                 break;
676           default: /* paranoia to prevent missing case values */
677                 exit_cleanup(RERR_UNSUPPORTED);
678         }
679 }
680
681 /* The sum buffer only needs to be as long as the current checksum's digest
682  * len, not MAX_DIGEST_LEN. Note that for CSUM_MD4_ARCHAIC that is the full
683  * MD4_DIGEST_LEN even if the file-list code is going to ignore all but the
684  * first 2 bytes of it. */
685 void sum_end(char *sum)
686 {
687 #ifdef USE_OPENSSL
688         if (cur_sum_evp_md) {
689                 EVP_DigestFinal_ex(ctx_evp, (uchar *)sum, NULL);
690         } else
691 #endif
692         switch (cur_sum_nni->num) {
693 #ifdef SUPPORT_XXHASH
694           case CSUM_XXH64:
695                 SIVAL64(sum, 0, XXH64_digest(xxh64_state));
696                 break;
697 #endif
698 #ifdef SUPPORT_XXH3
699           case CSUM_XXH3_64:
700                 SIVAL64(sum, 0, XXH3_64bits_digest(xxh3_state));
701                 break;
702           case CSUM_XXH3_128: {
703                 XXH128_hash_t digest = XXH3_128bits_digest(xxh3_state);
704                 SIVAL64(sum, 0, digest.low64);
705                 SIVAL64(sum, 8, digest.high64);
706                 break;
707           }
708 #endif
709           case CSUM_MD5:
710                 md5_result(&ctx_md, (uchar *)sum);
711                 break;
712           case CSUM_MD4:
713           case CSUM_MD4_OLD:
714                 mdfour_update(&ctx_md, (uchar *)ctx_md.buffer, sumresidue);
715                 mdfour_result(&ctx_md, (uchar *)sum);
716                 break;
717           case CSUM_MD4_BUSTED:
718           case CSUM_MD4_ARCHAIC:
719                 if (sumresidue)
720                         mdfour_update(&ctx_md, (uchar *)ctx_md.buffer, sumresidue);
721                 mdfour_result(&ctx_md, (uchar *)sum);
722                 break;
723           case CSUM_NONE:
724                 *sum = '\0';
725                 break;
726           default: /* paranoia to prevent missing case values */
727                 exit_cleanup(RERR_UNSUPPORTED);
728         }
729 }
730
731 #if defined SUPPORT_XXH3 || defined USE_OPENSSL
732 static void verify_digest(struct name_num_item *nni, BOOL check_auth_list)
733 {
734 #ifdef SUPPORT_XXH3
735         static int xxh3_result = 0;
736 #endif
737 #ifdef USE_OPENSSL
738         static int prior_num = 0, prior_flags = 0, prior_result = 0;
739 #endif
740
741 #ifdef SUPPORT_XXH3
742         if (nni->num == CSUM_XXH3_64 || nni->num == CSUM_XXH3_128) {
743                 if (!xxh3_result) {
744                         char buf[32816];
745                         int j;
746                         for (j = 0; j < (int)sizeof buf; j++)
747                                 buf[j] = ' ' + (j % 96);
748                         sum_init(nni, 0);
749                         sum_update(buf, 32816);
750                         sum_update(buf, 31152);
751                         sum_update(buf, 32474);
752                         sum_update(buf, 9322);
753                         xxh3_result = XXH3_64bits_digest(xxh3_state) != 0xadbcf16d4678d1de ? -1 : 1;
754                 }
755                 if (xxh3_result < 0)
756                         nni->num = CSUM_gone;
757                 return;
758         }
759 #endif
760
761 #ifdef USE_OPENSSL
762         if (BITS_SETnUNSET(nni->flags, NNI_EVP, NNI_BUILTIN|NNI_EVP_OK)) {
763                 if (nni->num == prior_num && nni->flags == prior_flags) {
764                         nni->flags = prior_result;
765                         if (!(nni->flags & NNI_EVP))
766                                 nni->num = CSUM_gone;
767                 } else {
768                         prior_num = nni->num;
769                         prior_flags = nni->flags;
770                         if (!csum_evp_md(nni))
771                                 nni->num = CSUM_gone;
772                         prior_result = nni->flags;
773                         if (check_auth_list && (nni = get_nni_by_num(&valid_auth_checksums, prior_num)) != NULL)
774                                 verify_digest(nni, False);
775                 }
776         }
777 #endif
778 }
779 #endif
780
781 void init_checksum_choices()
782 {
783 #if defined SUPPORT_XXH3 || defined USE_OPENSSL
784         struct name_num_item *nni;
785 #endif
786
787         if (initialized_choices)
788                 return;
789
790 #if defined USE_OPENSSL && OPENSSL_VERSION_NUMBER < 0x10100000L
791         OpenSSL_add_all_algorithms();
792 #endif
793
794 #if defined SUPPORT_XXH3 || defined USE_OPENSSL
795         for (nni = valid_checksums.list; nni->name; nni++)
796                 verify_digest(nni, True);
797
798         for (nni = valid_auth_checksums.list; nni->name; nni++)
799                 verify_digest(nni, False);
800 #endif
801
802         initialized_choices = 1;
803 }