Sync with 2.30.1
[git] / fsck.c
1 #include "cache.h"
2 #include "object-store.h"
3 #include "repository.h"
4 #include "object.h"
5 #include "blob.h"
6 #include "tree.h"
7 #include "tree-walk.h"
8 #include "commit.h"
9 #include "tag.h"
10 #include "fsck.h"
11 #include "refs.h"
12 #include "url.h"
13 #include "utf8.h"
14 #include "decorate.h"
15 #include "oidset.h"
16 #include "packfile.h"
17 #include "submodule-config.h"
18 #include "config.h"
19 #include "credential.h"
20 #include "help.h"
21
22 static struct oidset gitmodules_found = OIDSET_INIT;
23 static struct oidset gitmodules_done = OIDSET_INIT;
24
25 #define FSCK_FATAL -1
26 #define FSCK_INFO -2
27
28 #define FOREACH_MSG_ID(FUNC) \
29         /* fatal errors */ \
30         FUNC(NUL_IN_HEADER, FATAL) \
31         FUNC(UNTERMINATED_HEADER, FATAL) \
32         /* errors */ \
33         FUNC(BAD_DATE, ERROR) \
34         FUNC(BAD_DATE_OVERFLOW, ERROR) \
35         FUNC(BAD_EMAIL, ERROR) \
36         FUNC(BAD_NAME, ERROR) \
37         FUNC(BAD_OBJECT_SHA1, ERROR) \
38         FUNC(BAD_PARENT_SHA1, ERROR) \
39         FUNC(BAD_TAG_OBJECT, ERROR) \
40         FUNC(BAD_TIMEZONE, ERROR) \
41         FUNC(BAD_TREE, ERROR) \
42         FUNC(BAD_TREE_SHA1, ERROR) \
43         FUNC(BAD_TYPE, ERROR) \
44         FUNC(DUPLICATE_ENTRIES, ERROR) \
45         FUNC(MISSING_AUTHOR, ERROR) \
46         FUNC(MISSING_COMMITTER, ERROR) \
47         FUNC(MISSING_EMAIL, ERROR) \
48         FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
49         FUNC(MISSING_OBJECT, ERROR) \
50         FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
51         FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
52         FUNC(MISSING_TAG, ERROR) \
53         FUNC(MISSING_TAG_ENTRY, ERROR) \
54         FUNC(MISSING_TREE, ERROR) \
55         FUNC(MISSING_TREE_OBJECT, ERROR) \
56         FUNC(MISSING_TYPE, ERROR) \
57         FUNC(MISSING_TYPE_ENTRY, ERROR) \
58         FUNC(MULTIPLE_AUTHORS, ERROR) \
59         FUNC(TREE_NOT_SORTED, ERROR) \
60         FUNC(UNKNOWN_TYPE, ERROR) \
61         FUNC(ZERO_PADDED_DATE, ERROR) \
62         FUNC(GITMODULES_MISSING, ERROR) \
63         FUNC(GITMODULES_BLOB, ERROR) \
64         FUNC(GITMODULES_LARGE, ERROR) \
65         FUNC(GITMODULES_NAME, ERROR) \
66         FUNC(GITMODULES_SYMLINK, ERROR) \
67         FUNC(GITMODULES_URL, ERROR) \
68         FUNC(GITMODULES_PATH, ERROR) \
69         FUNC(GITMODULES_UPDATE, ERROR) \
70         /* warnings */ \
71         FUNC(BAD_FILEMODE, WARN) \
72         FUNC(EMPTY_NAME, WARN) \
73         FUNC(FULL_PATHNAME, WARN) \
74         FUNC(HAS_DOT, WARN) \
75         FUNC(HAS_DOTDOT, WARN) \
76         FUNC(HAS_DOTGIT, WARN) \
77         FUNC(NULL_SHA1, WARN) \
78         FUNC(ZERO_PADDED_FILEMODE, WARN) \
79         FUNC(NUL_IN_COMMIT, WARN) \
80         /* infos (reported as warnings, but ignored by default) */ \
81         FUNC(GITMODULES_PARSE, INFO) \
82         FUNC(BAD_TAG_NAME, INFO) \
83         FUNC(MISSING_TAGGER_ENTRY, INFO) \
84         /* ignored (elevated when requested) */ \
85         FUNC(EXTRA_HEADER_ENTRY, IGNORE)
86
87 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
88 enum fsck_msg_id {
89         FOREACH_MSG_ID(MSG_ID)
90         FSCK_MSG_MAX
91 };
92 #undef MSG_ID
93
94 #define STR(x) #x
95 #define MSG_ID(id, msg_type) { STR(id), NULL, NULL, FSCK_##msg_type },
96 static struct {
97         const char *id_string;
98         const char *downcased;
99         const char *camelcased;
100         int msg_type;
101 } msg_id_info[FSCK_MSG_MAX + 1] = {
102         FOREACH_MSG_ID(MSG_ID)
103         { NULL, NULL, NULL, -1 }
104 };
105 #undef MSG_ID
106
107 static void prepare_msg_ids(void)
108 {
109         int i;
110
111         if (msg_id_info[0].downcased)
112                 return;
113
114         /* convert id_string to lower case, without underscores. */
115         for (i = 0; i < FSCK_MSG_MAX; i++) {
116                 const char *p = msg_id_info[i].id_string;
117                 int len = strlen(p);
118                 char *q = xmalloc(len);
119
120                 msg_id_info[i].downcased = q;
121                 while (*p)
122                         if (*p == '_')
123                                 p++;
124                         else
125                                 *(q)++ = tolower(*(p)++);
126                 *q = '\0';
127
128                 p = msg_id_info[i].id_string;
129                 q = xmalloc(len);
130                 msg_id_info[i].camelcased = q;
131                 while (*p) {
132                         if (*p == '_') {
133                                 p++;
134                                 if (*p)
135                                         *q++ = *p++;
136                         } else {
137                                 *q++ = tolower(*p++);
138                         }
139                 }
140                 *q = '\0';
141         }
142 }
143
144 static int parse_msg_id(const char *text)
145 {
146         int i;
147
148         prepare_msg_ids();
149
150         for (i = 0; i < FSCK_MSG_MAX; i++)
151                 if (!strcmp(text, msg_id_info[i].downcased))
152                         return i;
153
154         return -1;
155 }
156
157 void list_config_fsck_msg_ids(struct string_list *list, const char *prefix)
158 {
159         int i;
160
161         prepare_msg_ids();
162
163         for (i = 0; i < FSCK_MSG_MAX; i++)
164                 list_config_item(list, prefix, msg_id_info[i].camelcased);
165 }
166
167 static int fsck_msg_type(enum fsck_msg_id msg_id,
168         struct fsck_options *options)
169 {
170         int msg_type;
171
172         assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
173
174         if (options->msg_type)
175                 msg_type = options->msg_type[msg_id];
176         else {
177                 msg_type = msg_id_info[msg_id].msg_type;
178                 if (options->strict && msg_type == FSCK_WARN)
179                         msg_type = FSCK_ERROR;
180         }
181
182         return msg_type;
183 }
184
185 static int parse_msg_type(const char *str)
186 {
187         if (!strcmp(str, "error"))
188                 return FSCK_ERROR;
189         else if (!strcmp(str, "warn"))
190                 return FSCK_WARN;
191         else if (!strcmp(str, "ignore"))
192                 return FSCK_IGNORE;
193         else
194                 die("Unknown fsck message type: '%s'", str);
195 }
196
197 int is_valid_msg_type(const char *msg_id, const char *msg_type)
198 {
199         if (parse_msg_id(msg_id) < 0)
200                 return 0;
201         parse_msg_type(msg_type);
202         return 1;
203 }
204
205 void fsck_set_msg_type(struct fsck_options *options,
206                 const char *msg_id, const char *msg_type)
207 {
208         int id = parse_msg_id(msg_id), type;
209
210         if (id < 0)
211                 die("Unhandled message id: %s", msg_id);
212         type = parse_msg_type(msg_type);
213
214         if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
215                 die("Cannot demote %s to %s", msg_id, msg_type);
216
217         if (!options->msg_type) {
218                 int i;
219                 int *msg_type;
220                 ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
221                 for (i = 0; i < FSCK_MSG_MAX; i++)
222                         msg_type[i] = fsck_msg_type(i, options);
223                 options->msg_type = msg_type;
224         }
225
226         options->msg_type[id] = type;
227 }
228
229 void fsck_set_msg_types(struct fsck_options *options, const char *values)
230 {
231         char *buf = xstrdup(values), *to_free = buf;
232         int done = 0;
233
234         while (!done) {
235                 int len = strcspn(buf, " ,|"), equal;
236
237                 done = !buf[len];
238                 if (!len) {
239                         buf++;
240                         continue;
241                 }
242                 buf[len] = '\0';
243
244                 for (equal = 0;
245                      equal < len && buf[equal] != '=' && buf[equal] != ':';
246                      equal++)
247                         buf[equal] = tolower(buf[equal]);
248                 buf[equal] = '\0';
249
250                 if (!strcmp(buf, "skiplist")) {
251                         if (equal == len)
252                                 die("skiplist requires a path");
253                         oidset_parse_file(&options->skiplist, buf + equal + 1);
254                         buf += len + 1;
255                         continue;
256                 }
257
258                 if (equal == len)
259                         die("Missing '=': '%s'", buf);
260
261                 fsck_set_msg_type(options, buf, buf + equal + 1);
262                 buf += len + 1;
263         }
264         free(to_free);
265 }
266
267 static void append_msg_id(struct strbuf *sb, const char *msg_id)
268 {
269         for (;;) {
270                 char c = *(msg_id)++;
271
272                 if (!c)
273                         break;
274                 if (c != '_')
275                         strbuf_addch(sb, tolower(c));
276                 else {
277                         assert(*msg_id);
278                         strbuf_addch(sb, *(msg_id)++);
279                 }
280         }
281
282         strbuf_addstr(sb, ": ");
283 }
284
285 static int object_on_skiplist(struct fsck_options *opts,
286                               const struct object_id *oid)
287 {
288         return opts && oid && oidset_contains(&opts->skiplist, oid);
289 }
290
291 __attribute__((format (printf, 5, 6)))
292 static int report(struct fsck_options *options,
293                   const struct object_id *oid, enum object_type object_type,
294                   enum fsck_msg_id id, const char *fmt, ...)
295 {
296         va_list ap;
297         struct strbuf sb = STRBUF_INIT;
298         int msg_type = fsck_msg_type(id, options), result;
299
300         if (msg_type == FSCK_IGNORE)
301                 return 0;
302
303         if (object_on_skiplist(options, oid))
304                 return 0;
305
306         if (msg_type == FSCK_FATAL)
307                 msg_type = FSCK_ERROR;
308         else if (msg_type == FSCK_INFO)
309                 msg_type = FSCK_WARN;
310
311         append_msg_id(&sb, msg_id_info[id].id_string);
312
313         va_start(ap, fmt);
314         strbuf_vaddf(&sb, fmt, ap);
315         result = options->error_func(options, oid, object_type,
316                                      msg_type, sb.buf);
317         strbuf_release(&sb);
318         va_end(ap);
319
320         return result;
321 }
322
323 void fsck_enable_object_names(struct fsck_options *options)
324 {
325         if (!options->object_names)
326                 options->object_names = kh_init_oid_map();
327 }
328
329 const char *fsck_get_object_name(struct fsck_options *options,
330                                  const struct object_id *oid)
331 {
332         khiter_t pos;
333         if (!options->object_names)
334                 return NULL;
335         pos = kh_get_oid_map(options->object_names, *oid);
336         if (pos >= kh_end(options->object_names))
337                 return NULL;
338         return kh_value(options->object_names, pos);
339 }
340
341 void fsck_put_object_name(struct fsck_options *options,
342                           const struct object_id *oid,
343                           const char *fmt, ...)
344 {
345         va_list ap;
346         struct strbuf buf = STRBUF_INIT;
347         khiter_t pos;
348         int hashret;
349
350         if (!options->object_names)
351                 return;
352
353         pos = kh_put_oid_map(options->object_names, *oid, &hashret);
354         if (!hashret)
355                 return;
356         va_start(ap, fmt);
357         strbuf_vaddf(&buf, fmt, ap);
358         kh_value(options->object_names, pos) = strbuf_detach(&buf, NULL);
359         va_end(ap);
360 }
361
362 const char *fsck_describe_object(struct fsck_options *options,
363                                  const struct object_id *oid)
364 {
365         static struct strbuf bufs[] = {
366                 STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
367         };
368         static int b = 0;
369         struct strbuf *buf;
370         const char *name = fsck_get_object_name(options, oid);
371
372         buf = bufs + b;
373         b = (b + 1) % ARRAY_SIZE(bufs);
374         strbuf_reset(buf);
375         strbuf_addstr(buf, oid_to_hex(oid));
376         if (name)
377                 strbuf_addf(buf, " (%s)", name);
378
379         return buf->buf;
380 }
381
382 static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
383 {
384         struct tree_desc desc;
385         struct name_entry entry;
386         int res = 0;
387         const char *name;
388
389         if (parse_tree(tree))
390                 return -1;
391
392         name = fsck_get_object_name(options, &tree->object.oid);
393         if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
394                 return -1;
395         while (tree_entry_gently(&desc, &entry)) {
396                 struct object *obj;
397                 int result;
398
399                 if (S_ISGITLINK(entry.mode))
400                         continue;
401
402                 if (S_ISDIR(entry.mode)) {
403                         obj = (struct object *)lookup_tree(the_repository, &entry.oid);
404                         if (name && obj)
405                                 fsck_put_object_name(options, &entry.oid, "%s%s/",
406                                                      name, entry.path);
407                         result = options->walk(obj, OBJ_TREE, data, options);
408                 }
409                 else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
410                         obj = (struct object *)lookup_blob(the_repository, &entry.oid);
411                         if (name && obj)
412                                 fsck_put_object_name(options, &entry.oid, "%s%s",
413                                                      name, entry.path);
414                         result = options->walk(obj, OBJ_BLOB, data, options);
415                 }
416                 else {
417                         result = error("in tree %s: entry %s has bad mode %.6o",
418                                        fsck_describe_object(options, &tree->object.oid),
419                                        entry.path, entry.mode);
420                 }
421                 if (result < 0)
422                         return result;
423                 if (!res)
424                         res = result;
425         }
426         return res;
427 }
428
429 static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
430 {
431         int counter = 0, generation = 0, name_prefix_len = 0;
432         struct commit_list *parents;
433         int res;
434         int result;
435         const char *name;
436
437         if (parse_commit(commit))
438                 return -1;
439
440         name = fsck_get_object_name(options, &commit->object.oid);
441         if (name)
442                 fsck_put_object_name(options, get_commit_tree_oid(commit),
443                                      "%s:", name);
444
445         result = options->walk((struct object *)get_commit_tree(commit),
446                                OBJ_TREE, data, options);
447         if (result < 0)
448                 return result;
449         res = result;
450
451         parents = commit->parents;
452         if (name && parents) {
453                 int len = strlen(name), power;
454
455                 if (len && name[len - 1] == '^') {
456                         generation = 1;
457                         name_prefix_len = len - 1;
458                 }
459                 else { /* parse ~<generation> suffix */
460                         for (generation = 0, power = 1;
461                              len && isdigit(name[len - 1]);
462                              power *= 10)
463                                 generation += power * (name[--len] - '0');
464                         if (power > 1 && len && name[len - 1] == '~')
465                                 name_prefix_len = len - 1;
466                 }
467         }
468
469         while (parents) {
470                 if (name) {
471                         struct object_id *oid = &parents->item->object.oid;
472
473                         if (counter++)
474                                 fsck_put_object_name(options, oid, "%s^%d",
475                                                      name, counter);
476                         else if (generation > 0)
477                                 fsck_put_object_name(options, oid, "%.*s~%d",
478                                                      name_prefix_len, name,
479                                                      generation + 1);
480                         else
481                                 fsck_put_object_name(options, oid, "%s^", name);
482                 }
483                 result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
484                 if (result < 0)
485                         return result;
486                 if (!res)
487                         res = result;
488                 parents = parents->next;
489         }
490         return res;
491 }
492
493 static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
494 {
495         const char *name = fsck_get_object_name(options, &tag->object.oid);
496
497         if (parse_tag(tag))
498                 return -1;
499         if (name)
500                 fsck_put_object_name(options, &tag->tagged->oid, "%s", name);
501         return options->walk(tag->tagged, OBJ_ANY, data, options);
502 }
503
504 int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
505 {
506         if (!obj)
507                 return -1;
508
509         if (obj->type == OBJ_NONE)
510                 parse_object(the_repository, &obj->oid);
511
512         switch (obj->type) {
513         case OBJ_BLOB:
514                 return 0;
515         case OBJ_TREE:
516                 return fsck_walk_tree((struct tree *)obj, data, options);
517         case OBJ_COMMIT:
518                 return fsck_walk_commit((struct commit *)obj, data, options);
519         case OBJ_TAG:
520                 return fsck_walk_tag((struct tag *)obj, data, options);
521         default:
522                 error("Unknown object type for %s",
523                       fsck_describe_object(options, &obj->oid));
524                 return -1;
525         }
526 }
527
528 struct name_stack {
529         const char **names;
530         size_t nr, alloc;
531 };
532
533 static void name_stack_push(struct name_stack *stack, const char *name)
534 {
535         ALLOC_GROW(stack->names, stack->nr + 1, stack->alloc);
536         stack->names[stack->nr++] = name;
537 }
538
539 static const char *name_stack_pop(struct name_stack *stack)
540 {
541         return stack->nr ? stack->names[--stack->nr] : NULL;
542 }
543
544 static void name_stack_clear(struct name_stack *stack)
545 {
546         FREE_AND_NULL(stack->names);
547         stack->nr = stack->alloc = 0;
548 }
549
550 /*
551  * The entries in a tree are ordered in the _path_ order,
552  * which means that a directory entry is ordered by adding
553  * a slash to the end of it.
554  *
555  * So a directory called "a" is ordered _after_ a file
556  * called "a.c", because "a/" sorts after "a.c".
557  */
558 #define TREE_UNORDERED (-1)
559 #define TREE_HAS_DUPS  (-2)
560
561 static int is_less_than_slash(unsigned char c)
562 {
563         return '\0' < c && c < '/';
564 }
565
566 static int verify_ordered(unsigned mode1, const char *name1,
567                           unsigned mode2, const char *name2,
568                           struct name_stack *candidates)
569 {
570         int len1 = strlen(name1);
571         int len2 = strlen(name2);
572         int len = len1 < len2 ? len1 : len2;
573         unsigned char c1, c2;
574         int cmp;
575
576         cmp = memcmp(name1, name2, len);
577         if (cmp < 0)
578                 return 0;
579         if (cmp > 0)
580                 return TREE_UNORDERED;
581
582         /*
583          * Ok, the first <len> characters are the same.
584          * Now we need to order the next one, but turn
585          * a '\0' into a '/' for a directory entry.
586          */
587         c1 = name1[len];
588         c2 = name2[len];
589         if (!c1 && !c2)
590                 /*
591                  * git-write-tree used to write out a nonsense tree that has
592                  * entries with the same name, one blob and one tree.  Make
593                  * sure we do not have duplicate entries.
594                  */
595                 return TREE_HAS_DUPS;
596         if (!c1 && S_ISDIR(mode1))
597                 c1 = '/';
598         if (!c2 && S_ISDIR(mode2))
599                 c2 = '/';
600
601         /*
602          * There can be non-consecutive duplicates due to the implicitly
603          * added slash, e.g.:
604          *
605          *   foo
606          *   foo.bar
607          *   foo.bar.baz
608          *   foo.bar/
609          *   foo/
610          *
611          * Record non-directory candidates (like "foo" and "foo.bar" in
612          * the example) on a stack and check directory candidates (like
613          * foo/" and "foo.bar/") against that stack.
614          */
615         if (!c1 && is_less_than_slash(c2)) {
616                 name_stack_push(candidates, name1);
617         } else if (c2 == '/' && is_less_than_slash(c1)) {
618                 for (;;) {
619                         const char *p;
620                         const char *f_name = name_stack_pop(candidates);
621
622                         if (!f_name)
623                                 break;
624                         if (!skip_prefix(name2, f_name, &p))
625                                 continue;
626                         if (!*p)
627                                 return TREE_HAS_DUPS;
628                         if (is_less_than_slash(*p)) {
629                                 name_stack_push(candidates, f_name);
630                                 break;
631                         }
632                 }
633         }
634
635         return c1 < c2 ? 0 : TREE_UNORDERED;
636 }
637
638 static int fsck_tree(const struct object_id *oid,
639                      const char *buffer, unsigned long size,
640                      struct fsck_options *options)
641 {
642         int retval = 0;
643         int has_null_sha1 = 0;
644         int has_full_path = 0;
645         int has_empty_name = 0;
646         int has_dot = 0;
647         int has_dotdot = 0;
648         int has_dotgit = 0;
649         int has_zero_pad = 0;
650         int has_bad_modes = 0;
651         int has_dup_entries = 0;
652         int not_properly_sorted = 0;
653         struct tree_desc desc;
654         unsigned o_mode;
655         const char *o_name;
656         struct name_stack df_dup_candidates = { NULL };
657
658         if (init_tree_desc_gently(&desc, buffer, size)) {
659                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
660                 return retval;
661         }
662
663         o_mode = 0;
664         o_name = NULL;
665
666         while (desc.size) {
667                 unsigned short mode;
668                 const char *name, *backslash;
669                 const struct object_id *oid;
670
671                 oid = tree_entry_extract(&desc, &name, &mode);
672
673                 has_null_sha1 |= is_null_oid(oid);
674                 has_full_path |= !!strchr(name, '/');
675                 has_empty_name |= !*name;
676                 has_dot |= !strcmp(name, ".");
677                 has_dotdot |= !strcmp(name, "..");
678                 has_dotgit |= is_hfs_dotgit(name) || is_ntfs_dotgit(name);
679                 has_zero_pad |= *(char *)desc.buffer == '0';
680
681                 if (is_hfs_dotgitmodules(name) || is_ntfs_dotgitmodules(name)) {
682                         if (!S_ISLNK(mode))
683                                 oidset_insert(&gitmodules_found, oid);
684                         else
685                                 retval += report(options,
686                                                  oid, OBJ_TREE,
687                                                  FSCK_MSG_GITMODULES_SYMLINK,
688                                                  ".gitmodules is a symbolic link");
689                 }
690
691                 if ((backslash = strchr(name, '\\'))) {
692                         while (backslash) {
693                                 backslash++;
694                                 has_dotgit |= is_ntfs_dotgit(backslash);
695                                 if (is_ntfs_dotgitmodules(backslash)) {
696                                         if (!S_ISLNK(mode))
697                                                 oidset_insert(&gitmodules_found, oid);
698                                         else
699                                                 retval += report(options, oid, OBJ_TREE,
700                                                                  FSCK_MSG_GITMODULES_SYMLINK,
701                                                                  ".gitmodules is a symbolic link");
702                                 }
703                                 backslash = strchr(backslash, '\\');
704                         }
705                 }
706
707                 if (update_tree_entry_gently(&desc)) {
708                         retval += report(options, oid, OBJ_TREE, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
709                         break;
710                 }
711
712                 switch (mode) {
713                 /*
714                  * Standard modes..
715                  */
716                 case S_IFREG | 0755:
717                 case S_IFREG | 0644:
718                 case S_IFLNK:
719                 case S_IFDIR:
720                 case S_IFGITLINK:
721                         break;
722                 /*
723                  * This is nonstandard, but we had a few of these
724                  * early on when we honored the full set of mode
725                  * bits..
726                  */
727                 case S_IFREG | 0664:
728                         if (!options->strict)
729                                 break;
730                         /* fallthrough */
731                 default:
732                         has_bad_modes = 1;
733                 }
734
735                 if (o_name) {
736                         switch (verify_ordered(o_mode, o_name, mode, name,
737                                                &df_dup_candidates)) {
738                         case TREE_UNORDERED:
739                                 not_properly_sorted = 1;
740                                 break;
741                         case TREE_HAS_DUPS:
742                                 has_dup_entries = 1;
743                                 break;
744                         default:
745                                 break;
746                         }
747                 }
748
749                 o_mode = mode;
750                 o_name = name;
751         }
752
753         name_stack_clear(&df_dup_candidates);
754
755         if (has_null_sha1)
756                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
757         if (has_full_path)
758                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
759         if (has_empty_name)
760                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
761         if (has_dot)
762                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_HAS_DOT, "contains '.'");
763         if (has_dotdot)
764                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_HAS_DOTDOT, "contains '..'");
765         if (has_dotgit)
766                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
767         if (has_zero_pad)
768                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
769         if (has_bad_modes)
770                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
771         if (has_dup_entries)
772                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
773         if (not_properly_sorted)
774                 retval += report(options, oid, OBJ_TREE, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
775         return retval;
776 }
777
778 static int verify_headers(const void *data, unsigned long size,
779                           const struct object_id *oid, enum object_type type,
780                           struct fsck_options *options)
781 {
782         const char *buffer = (const char *)data;
783         unsigned long i;
784
785         for (i = 0; i < size; i++) {
786                 switch (buffer[i]) {
787                 case '\0':
788                         return report(options, oid, type,
789                                 FSCK_MSG_NUL_IN_HEADER,
790                                 "unterminated header: NUL at offset %ld", i);
791                 case '\n':
792                         if (i + 1 < size && buffer[i + 1] == '\n')
793                                 return 0;
794                 }
795         }
796
797         /*
798          * We did not find double-LF that separates the header
799          * and the body.  Not having a body is not a crime but
800          * we do want to see the terminating LF for the last header
801          * line.
802          */
803         if (size && buffer[size - 1] == '\n')
804                 return 0;
805
806         return report(options, oid, type,
807                 FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
808 }
809
810 static int fsck_ident(const char **ident,
811                       const struct object_id *oid, enum object_type type,
812                       struct fsck_options *options)
813 {
814         const char *p = *ident;
815         char *end;
816
817         *ident = strchrnul(*ident, '\n');
818         if (**ident == '\n')
819                 (*ident)++;
820
821         if (*p == '<')
822                 return report(options, oid, type, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
823         p += strcspn(p, "<>\n");
824         if (*p == '>')
825                 return report(options, oid, type, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
826         if (*p != '<')
827                 return report(options, oid, type, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
828         if (p[-1] != ' ')
829                 return report(options, oid, type, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
830         p++;
831         p += strcspn(p, "<>\n");
832         if (*p != '>')
833                 return report(options, oid, type, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
834         p++;
835         if (*p != ' ')
836                 return report(options, oid, type, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
837         p++;
838         if (*p == '0' && p[1] != ' ')
839                 return report(options, oid, type, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
840         if (date_overflows(parse_timestamp(p, &end, 10)))
841                 return report(options, oid, type, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
842         if ((end == p || *end != ' '))
843                 return report(options, oid, type, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
844         p = end + 1;
845         if ((*p != '+' && *p != '-') ||
846             !isdigit(p[1]) ||
847             !isdigit(p[2]) ||
848             !isdigit(p[3]) ||
849             !isdigit(p[4]) ||
850             (p[5] != '\n'))
851                 return report(options, oid, type, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
852         p += 6;
853         return 0;
854 }
855
856 static int fsck_commit(const struct object_id *oid,
857                        const char *buffer, unsigned long size,
858                        struct fsck_options *options)
859 {
860         struct object_id tree_oid, parent_oid;
861         unsigned author_count;
862         int err;
863         const char *buffer_begin = buffer;
864         const char *p;
865
866         if (verify_headers(buffer, size, oid, OBJ_COMMIT, options))
867                 return -1;
868
869         if (!skip_prefix(buffer, "tree ", &buffer))
870                 return report(options, oid, OBJ_COMMIT, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
871         if (parse_oid_hex(buffer, &tree_oid, &p) || *p != '\n') {
872                 err = report(options, oid, OBJ_COMMIT, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
873                 if (err)
874                         return err;
875         }
876         buffer = p + 1;
877         while (skip_prefix(buffer, "parent ", &buffer)) {
878                 if (parse_oid_hex(buffer, &parent_oid, &p) || *p != '\n') {
879                         err = report(options, oid, OBJ_COMMIT, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
880                         if (err)
881                                 return err;
882                 }
883                 buffer = p + 1;
884         }
885         author_count = 0;
886         while (skip_prefix(buffer, "author ", &buffer)) {
887                 author_count++;
888                 err = fsck_ident(&buffer, oid, OBJ_COMMIT, options);
889                 if (err)
890                         return err;
891         }
892         if (author_count < 1)
893                 err = report(options, oid, OBJ_COMMIT, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
894         else if (author_count > 1)
895                 err = report(options, oid, OBJ_COMMIT, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
896         if (err)
897                 return err;
898         if (!skip_prefix(buffer, "committer ", &buffer))
899                 return report(options, oid, OBJ_COMMIT, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
900         err = fsck_ident(&buffer, oid, OBJ_COMMIT, options);
901         if (err)
902                 return err;
903         if (memchr(buffer_begin, '\0', size)) {
904                 err = report(options, oid, OBJ_COMMIT, FSCK_MSG_NUL_IN_COMMIT,
905                              "NUL byte in the commit object body");
906                 if (err)
907                         return err;
908         }
909         return 0;
910 }
911
912 static int fsck_tag(const struct object_id *oid, const char *buffer,
913                     unsigned long size, struct fsck_options *options)
914 {
915         struct object_id tagged_oid;
916         int tagged_type;
917         return fsck_tag_standalone(oid, buffer, size, options, &tagged_oid,
918                                    &tagged_type);
919 }
920
921 int fsck_tag_standalone(const struct object_id *oid, const char *buffer,
922                         unsigned long size, struct fsck_options *options,
923                         struct object_id *tagged_oid,
924                         int *tagged_type)
925 {
926         int ret = 0;
927         char *eol;
928         struct strbuf sb = STRBUF_INIT;
929         const char *p;
930
931         ret = verify_headers(buffer, size, oid, OBJ_TAG, options);
932         if (ret)
933                 goto done;
934
935         if (!skip_prefix(buffer, "object ", &buffer)) {
936                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
937                 goto done;
938         }
939         if (parse_oid_hex(buffer, tagged_oid, &p) || *p != '\n') {
940                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
941                 if (ret)
942                         goto done;
943         }
944         buffer = p + 1;
945
946         if (!skip_prefix(buffer, "type ", &buffer)) {
947                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
948                 goto done;
949         }
950         eol = strchr(buffer, '\n');
951         if (!eol) {
952                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
953                 goto done;
954         }
955         *tagged_type = type_from_string_gently(buffer, eol - buffer, 1);
956         if (*tagged_type < 0)
957                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
958         if (ret)
959                 goto done;
960         buffer = eol + 1;
961
962         if (!skip_prefix(buffer, "tag ", &buffer)) {
963                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
964                 goto done;
965         }
966         eol = strchr(buffer, '\n');
967         if (!eol) {
968                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
969                 goto done;
970         }
971         strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
972         if (check_refname_format(sb.buf, 0)) {
973                 ret = report(options, oid, OBJ_TAG,
974                              FSCK_MSG_BAD_TAG_NAME,
975                              "invalid 'tag' name: %.*s",
976                              (int)(eol - buffer), buffer);
977                 if (ret)
978                         goto done;
979         }
980         buffer = eol + 1;
981
982         if (!skip_prefix(buffer, "tagger ", &buffer)) {
983                 /* early tags do not contain 'tagger' lines; warn only */
984                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
985                 if (ret)
986                         goto done;
987         }
988         else
989                 ret = fsck_ident(&buffer, oid, OBJ_TAG, options);
990         if (!*buffer)
991                 goto done;
992
993         if (!starts_with(buffer, "\n")) {
994                 /*
995                  * The verify_headers() check will allow
996                  * e.g. "[...]tagger <tagger>\nsome
997                  * garbage\n\nmessage" to pass, thinking "some
998                  * garbage" could be a custom header. E.g. "mktag"
999                  * doesn't want any unknown headers.
1000                  */
1001                 ret = report(options, oid, OBJ_TAG, FSCK_MSG_EXTRA_HEADER_ENTRY, "invalid format - extra header(s) after 'tagger'");
1002                 if (ret)
1003                         goto done;
1004         }
1005
1006 done:
1007         strbuf_release(&sb);
1008         return ret;
1009 }
1010
1011 /*
1012  * Like builtin/submodule--helper.c's starts_with_dot_slash, but without
1013  * relying on the platform-dependent is_dir_sep helper.
1014  *
1015  * This is for use in checking whether a submodule URL is interpreted as
1016  * relative to the current directory on any platform, since \ is a
1017  * directory separator on Windows but not on other platforms.
1018  */
1019 static int starts_with_dot_slash(const char *str)
1020 {
1021         return str[0] == '.' && (str[1] == '/' || str[1] == '\\');
1022 }
1023
1024 /*
1025  * Like starts_with_dot_slash, this is a variant of submodule--helper's
1026  * helper of the same name with the twist that it accepts backslash as a
1027  * directory separator even on non-Windows platforms.
1028  */
1029 static int starts_with_dot_dot_slash(const char *str)
1030 {
1031         return str[0] == '.' && starts_with_dot_slash(str + 1);
1032 }
1033
1034 static int submodule_url_is_relative(const char *url)
1035 {
1036         return starts_with_dot_slash(url) || starts_with_dot_dot_slash(url);
1037 }
1038
1039 /*
1040  * Count directory components that a relative submodule URL should chop
1041  * from the remote_url it is to be resolved against.
1042  *
1043  * In other words, this counts "../" components at the start of a
1044  * submodule URL.
1045  *
1046  * Returns the number of directory components to chop and writes a
1047  * pointer to the next character of url after all leading "./" and
1048  * "../" components to out.
1049  */
1050 static int count_leading_dotdots(const char *url, const char **out)
1051 {
1052         int result = 0;
1053         while (1) {
1054                 if (starts_with_dot_dot_slash(url)) {
1055                         result++;
1056                         url += strlen("../");
1057                         continue;
1058                 }
1059                 if (starts_with_dot_slash(url)) {
1060                         url += strlen("./");
1061                         continue;
1062                 }
1063                 *out = url;
1064                 return result;
1065         }
1066 }
1067 /*
1068  * Check whether a transport is implemented by git-remote-curl.
1069  *
1070  * If it is, returns 1 and writes the URL that would be passed to
1071  * git-remote-curl to the "out" parameter.
1072  *
1073  * Otherwise, returns 0 and leaves "out" untouched.
1074  *
1075  * Examples:
1076  *   http::https://example.com/repo.git -> 1, https://example.com/repo.git
1077  *   https://example.com/repo.git -> 1, https://example.com/repo.git
1078  *   git://example.com/repo.git -> 0
1079  *
1080  * This is for use in checking for previously exploitable bugs that
1081  * required a submodule URL to be passed to git-remote-curl.
1082  */
1083 static int url_to_curl_url(const char *url, const char **out)
1084 {
1085         /*
1086          * We don't need to check for case-aliases, "http.exe", and so
1087          * on because in the default configuration, is_transport_allowed
1088          * prevents URLs with those schemes from being cloned
1089          * automatically.
1090          */
1091         if (skip_prefix(url, "http::", out) ||
1092             skip_prefix(url, "https::", out) ||
1093             skip_prefix(url, "ftp::", out) ||
1094             skip_prefix(url, "ftps::", out))
1095                 return 1;
1096         if (starts_with(url, "http://") ||
1097             starts_with(url, "https://") ||
1098             starts_with(url, "ftp://") ||
1099             starts_with(url, "ftps://")) {
1100                 *out = url;
1101                 return 1;
1102         }
1103         return 0;
1104 }
1105
1106 static int check_submodule_url(const char *url)
1107 {
1108         const char *curl_url;
1109
1110         if (looks_like_command_line_option(url))
1111                 return -1;
1112
1113         if (submodule_url_is_relative(url) || starts_with(url, "git://")) {
1114                 char *decoded;
1115                 const char *next;
1116                 int has_nl;
1117
1118                 /*
1119                  * This could be appended to an http URL and url-decoded;
1120                  * check for malicious characters.
1121                  */
1122                 decoded = url_decode(url);
1123                 has_nl = !!strchr(decoded, '\n');
1124
1125                 free(decoded);
1126                 if (has_nl)
1127                         return -1;
1128
1129                 /*
1130                  * URLs which escape their root via "../" can overwrite
1131                  * the host field and previous components, resolving to
1132                  * URLs like https::example.com/submodule.git and
1133                  * https:///example.com/submodule.git that were
1134                  * susceptible to CVE-2020-11008.
1135                  */
1136                 if (count_leading_dotdots(url, &next) > 0 &&
1137                     (*next == ':' || *next == '/'))
1138                         return -1;
1139         }
1140
1141         else if (url_to_curl_url(url, &curl_url)) {
1142                 struct credential c = CREDENTIAL_INIT;
1143                 int ret = 0;
1144                 if (credential_from_url_gently(&c, curl_url, 1) ||
1145                     !*c.host)
1146                         ret = -1;
1147                 credential_clear(&c);
1148                 return ret;
1149         }
1150
1151         return 0;
1152 }
1153
1154 struct fsck_gitmodules_data {
1155         const struct object_id *oid;
1156         struct fsck_options *options;
1157         int ret;
1158 };
1159
1160 static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
1161 {
1162         struct fsck_gitmodules_data *data = vdata;
1163         const char *subsection, *key;
1164         size_t subsection_len;
1165         char *name;
1166
1167         if (parse_config_key(var, "submodule", &subsection, &subsection_len, &key) < 0 ||
1168             !subsection)
1169                 return 0;
1170
1171         name = xmemdupz(subsection, subsection_len);
1172         if (check_submodule_name(name) < 0)
1173                 data->ret |= report(data->options,
1174                                     data->oid, OBJ_BLOB,
1175                                     FSCK_MSG_GITMODULES_NAME,
1176                                     "disallowed submodule name: %s",
1177                                     name);
1178         if (!strcmp(key, "url") && value &&
1179             check_submodule_url(value) < 0)
1180                 data->ret |= report(data->options,
1181                                     data->oid, OBJ_BLOB,
1182                                     FSCK_MSG_GITMODULES_URL,
1183                                     "disallowed submodule url: %s",
1184                                     value);
1185         if (!strcmp(key, "path") && value &&
1186             looks_like_command_line_option(value))
1187                 data->ret |= report(data->options,
1188                                     data->oid, OBJ_BLOB,
1189                                     FSCK_MSG_GITMODULES_PATH,
1190                                     "disallowed submodule path: %s",
1191                                     value);
1192         if (!strcmp(key, "update") && value &&
1193             parse_submodule_update_type(value) == SM_UPDATE_COMMAND)
1194                 data->ret |= report(data->options, data->oid, OBJ_BLOB,
1195                                     FSCK_MSG_GITMODULES_UPDATE,
1196                                     "disallowed submodule update setting: %s",
1197                                     value);
1198         free(name);
1199
1200         return 0;
1201 }
1202
1203 static int fsck_blob(const struct object_id *oid, const char *buf,
1204                      unsigned long size, struct fsck_options *options)
1205 {
1206         struct fsck_gitmodules_data data;
1207         struct config_options config_opts = { 0 };
1208
1209         if (!oidset_contains(&gitmodules_found, oid))
1210                 return 0;
1211         oidset_insert(&gitmodules_done, oid);
1212
1213         if (object_on_skiplist(options, oid))
1214                 return 0;
1215
1216         if (!buf) {
1217                 /*
1218                  * A missing buffer here is a sign that the caller found the
1219                  * blob too gigantic to load into memory. Let's just consider
1220                  * that an error.
1221                  */
1222                 return report(options, oid, OBJ_BLOB,
1223                               FSCK_MSG_GITMODULES_LARGE,
1224                               ".gitmodules too large to parse");
1225         }
1226
1227         data.oid = oid;
1228         data.options = options;
1229         data.ret = 0;
1230         config_opts.error_action = CONFIG_ERROR_SILENT;
1231         if (git_config_from_mem(fsck_gitmodules_fn, CONFIG_ORIGIN_BLOB,
1232                                 ".gitmodules", buf, size, &data, &config_opts))
1233                 data.ret |= report(options, oid, OBJ_BLOB,
1234                                    FSCK_MSG_GITMODULES_PARSE,
1235                                    "could not parse gitmodules blob");
1236
1237         return data.ret;
1238 }
1239
1240 int fsck_object(struct object *obj, void *data, unsigned long size,
1241         struct fsck_options *options)
1242 {
1243         if (!obj)
1244                 return report(options, NULL, OBJ_NONE, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
1245
1246         if (obj->type == OBJ_BLOB)
1247                 return fsck_blob(&obj->oid, data, size, options);
1248         if (obj->type == OBJ_TREE)
1249                 return fsck_tree(&obj->oid, data, size, options);
1250         if (obj->type == OBJ_COMMIT)
1251                 return fsck_commit(&obj->oid, data, size, options);
1252         if (obj->type == OBJ_TAG)
1253                 return fsck_tag(&obj->oid, data, size, options);
1254
1255         return report(options, &obj->oid, obj->type,
1256                       FSCK_MSG_UNKNOWN_TYPE,
1257                       "unknown type '%d' (internal fsck error)",
1258                       obj->type);
1259 }
1260
1261 int fsck_error_function(struct fsck_options *o,
1262                         const struct object_id *oid,
1263                         enum object_type object_type,
1264                         int msg_type, const char *message)
1265 {
1266         if (msg_type == FSCK_WARN) {
1267                 warning("object %s: %s", fsck_describe_object(o, oid), message);
1268                 return 0;
1269         }
1270         error("object %s: %s", fsck_describe_object(o, oid), message);
1271         return 1;
1272 }
1273
1274 int fsck_finish(struct fsck_options *options)
1275 {
1276         int ret = 0;
1277         struct oidset_iter iter;
1278         const struct object_id *oid;
1279
1280         oidset_iter_init(&gitmodules_found, &iter);
1281         while ((oid = oidset_iter_next(&iter))) {
1282                 enum object_type type;
1283                 unsigned long size;
1284                 char *buf;
1285
1286                 if (oidset_contains(&gitmodules_done, oid))
1287                         continue;
1288
1289                 buf = read_object_file(oid, &type, &size);
1290                 if (!buf) {
1291                         if (is_promisor_object(oid))
1292                                 continue;
1293                         ret |= report(options,
1294                                       oid, OBJ_BLOB,
1295                                       FSCK_MSG_GITMODULES_MISSING,
1296                                       "unable to read .gitmodules blob");
1297                         continue;
1298                 }
1299
1300                 if (type == OBJ_BLOB)
1301                         ret |= fsck_blob(oid, buf, size, options);
1302                 else
1303                         ret |= report(options,
1304                                       oid, type,
1305                                       FSCK_MSG_GITMODULES_BLOB,
1306                                       "non-blob found at .gitmodules");
1307                 free(buf);
1308         }
1309
1310
1311         oidset_clear(&gitmodules_found);
1312         oidset_clear(&gitmodules_done);
1313         return ret;
1314 }
1315
1316 int fsck_config_internal(const char *var, const char *value, void *cb,
1317                          struct fsck_options *options)
1318 {
1319         if (strcmp(var, "fsck.skiplist") == 0) {
1320                 const char *path;
1321                 struct strbuf sb = STRBUF_INIT;
1322
1323                 if (git_config_pathname(&path, var, value))
1324                         return 1;
1325                 strbuf_addf(&sb, "skiplist=%s", path);
1326                 free((char *)path);
1327                 fsck_set_msg_types(options, sb.buf);
1328                 strbuf_release(&sb);
1329                 return 0;
1330         }
1331
1332         if (skip_prefix(var, "fsck.", &var)) {
1333                 fsck_set_msg_type(options, var, value);
1334                 return 0;
1335         }
1336
1337         return git_default_config(var, value, cb);
1338 }