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