Imported Upstream version 2.17.3
[platform/upstream/git.git] / fsck.c
1 #include "cache.h"
2 #include "object.h"
3 #include "blob.h"
4 #include "tree.h"
5 #include "tree-walk.h"
6 #include "commit.h"
7 #include "tag.h"
8 #include "fsck.h"
9 #include "refs.h"
10 #include "utf8.h"
11 #include "sha1-array.h"
12 #include "decorate.h"
13 #include "oidset.h"
14 #include "packfile.h"
15 #include "submodule-config.h"
16 #include "config.h"
17
18 static struct oidset gitmodules_found = OIDSET_INIT;
19 static struct oidset gitmodules_done = OIDSET_INIT;
20
21 #define FSCK_FATAL -1
22 #define FSCK_INFO -2
23
24 #define FOREACH_MSG_ID(FUNC) \
25         /* fatal errors */ \
26         FUNC(NUL_IN_HEADER, FATAL) \
27         FUNC(UNTERMINATED_HEADER, FATAL) \
28         /* errors */ \
29         FUNC(BAD_DATE, ERROR) \
30         FUNC(BAD_DATE_OVERFLOW, ERROR) \
31         FUNC(BAD_EMAIL, ERROR) \
32         FUNC(BAD_NAME, ERROR) \
33         FUNC(BAD_OBJECT_SHA1, ERROR) \
34         FUNC(BAD_PARENT_SHA1, ERROR) \
35         FUNC(BAD_TAG_OBJECT, ERROR) \
36         FUNC(BAD_TIMEZONE, ERROR) \
37         FUNC(BAD_TREE, ERROR) \
38         FUNC(BAD_TREE_SHA1, ERROR) \
39         FUNC(BAD_TYPE, ERROR) \
40         FUNC(DUPLICATE_ENTRIES, ERROR) \
41         FUNC(MISSING_AUTHOR, ERROR) \
42         FUNC(MISSING_COMMITTER, ERROR) \
43         FUNC(MISSING_EMAIL, ERROR) \
44         FUNC(MISSING_GRAFT, ERROR) \
45         FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
46         FUNC(MISSING_OBJECT, ERROR) \
47         FUNC(MISSING_PARENT, ERROR) \
48         FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
49         FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
50         FUNC(MISSING_TAG, ERROR) \
51         FUNC(MISSING_TAG_ENTRY, ERROR) \
52         FUNC(MISSING_TAG_OBJECT, ERROR) \
53         FUNC(MISSING_TREE, ERROR) \
54         FUNC(MISSING_TREE_OBJECT, ERROR) \
55         FUNC(MISSING_TYPE, ERROR) \
56         FUNC(MISSING_TYPE_ENTRY, ERROR) \
57         FUNC(MULTIPLE_AUTHORS, ERROR) \
58         FUNC(TAG_OBJECT_NOT_TAG, 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_PARSE, 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(BAD_TAG_NAME, INFO) \
82         FUNC(MISSING_TAGGER_ENTRY, INFO)
83
84 #define MSG_ID(id, msg_type) FSCK_MSG_##id,
85 enum fsck_msg_id {
86         FOREACH_MSG_ID(MSG_ID)
87         FSCK_MSG_MAX
88 };
89 #undef MSG_ID
90
91 #define STR(x) #x
92 #define MSG_ID(id, msg_type) { STR(id), NULL, FSCK_##msg_type },
93 static struct {
94         const char *id_string;
95         const char *downcased;
96         int msg_type;
97 } msg_id_info[FSCK_MSG_MAX + 1] = {
98         FOREACH_MSG_ID(MSG_ID)
99         { NULL, NULL, -1 }
100 };
101 #undef MSG_ID
102
103 static int parse_msg_id(const char *text)
104 {
105         int i;
106
107         if (!msg_id_info[0].downcased) {
108                 /* convert id_string to lower case, without underscores. */
109                 for (i = 0; i < FSCK_MSG_MAX; i++) {
110                         const char *p = msg_id_info[i].id_string;
111                         int len = strlen(p);
112                         char *q = xmalloc(len);
113
114                         msg_id_info[i].downcased = q;
115                         while (*p)
116                                 if (*p == '_')
117                                         p++;
118                                 else
119                                         *(q)++ = tolower(*(p)++);
120                         *q = '\0';
121                 }
122         }
123
124         for (i = 0; i < FSCK_MSG_MAX; i++)
125                 if (!strcmp(text, msg_id_info[i].downcased))
126                         return i;
127
128         return -1;
129 }
130
131 static int fsck_msg_type(enum fsck_msg_id msg_id,
132         struct fsck_options *options)
133 {
134         int msg_type;
135
136         assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
137
138         if (options->msg_type)
139                 msg_type = options->msg_type[msg_id];
140         else {
141                 msg_type = msg_id_info[msg_id].msg_type;
142                 if (options->strict && msg_type == FSCK_WARN)
143                         msg_type = FSCK_ERROR;
144         }
145
146         return msg_type;
147 }
148
149 static void init_skiplist(struct fsck_options *options, const char *path)
150 {
151         static struct oid_array skiplist = OID_ARRAY_INIT;
152         int sorted, fd;
153         char buffer[GIT_MAX_HEXSZ + 1];
154         struct object_id oid;
155
156         if (options->skiplist)
157                 sorted = options->skiplist->sorted;
158         else {
159                 sorted = 1;
160                 options->skiplist = &skiplist;
161         }
162
163         fd = open(path, O_RDONLY);
164         if (fd < 0)
165                 die("Could not open skip list: %s", path);
166         for (;;) {
167                 const char *p;
168                 int result = read_in_full(fd, buffer, sizeof(buffer));
169                 if (result < 0)
170                         die_errno("Could not read '%s'", path);
171                 if (!result)
172                         break;
173                 if (parse_oid_hex(buffer, &oid, &p) || *p != '\n')
174                         die("Invalid SHA-1: %s", buffer);
175                 oid_array_append(&skiplist, &oid);
176                 if (sorted && skiplist.nr > 1 &&
177                                 oidcmp(&skiplist.oid[skiplist.nr - 2],
178                                        &oid) > 0)
179                         sorted = 0;
180         }
181         close(fd);
182
183         if (sorted)
184                 skiplist.sorted = 1;
185 }
186
187 static int parse_msg_type(const char *str)
188 {
189         if (!strcmp(str, "error"))
190                 return FSCK_ERROR;
191         else if (!strcmp(str, "warn"))
192                 return FSCK_WARN;
193         else if (!strcmp(str, "ignore"))
194                 return FSCK_IGNORE;
195         else
196                 die("Unknown fsck message type: '%s'", str);
197 }
198
199 int is_valid_msg_type(const char *msg_id, const char *msg_type)
200 {
201         if (parse_msg_id(msg_id) < 0)
202                 return 0;
203         parse_msg_type(msg_type);
204         return 1;
205 }
206
207 void fsck_set_msg_type(struct fsck_options *options,
208                 const char *msg_id, const char *msg_type)
209 {
210         int id = parse_msg_id(msg_id), type;
211
212         if (id < 0)
213                 die("Unhandled message id: %s", msg_id);
214         type = parse_msg_type(msg_type);
215
216         if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
217                 die("Cannot demote %s to %s", msg_id, msg_type);
218
219         if (!options->msg_type) {
220                 int i;
221                 int *msg_type;
222                 ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
223                 for (i = 0; i < FSCK_MSG_MAX; i++)
224                         msg_type[i] = fsck_msg_type(i, options);
225                 options->msg_type = msg_type;
226         }
227
228         options->msg_type[id] = type;
229 }
230
231 void fsck_set_msg_types(struct fsck_options *options, const char *values)
232 {
233         char *buf = xstrdup(values), *to_free = buf;
234         int done = 0;
235
236         while (!done) {
237                 int len = strcspn(buf, " ,|"), equal;
238
239                 done = !buf[len];
240                 if (!len) {
241                         buf++;
242                         continue;
243                 }
244                 buf[len] = '\0';
245
246                 for (equal = 0;
247                      equal < len && buf[equal] != '=' && buf[equal] != ':';
248                      equal++)
249                         buf[equal] = tolower(buf[equal]);
250                 buf[equal] = '\0';
251
252                 if (!strcmp(buf, "skiplist")) {
253                         if (equal == len)
254                                 die("skiplist requires a path");
255                         init_skiplist(options, buf + equal + 1);
256                         buf += len + 1;
257                         continue;
258                 }
259
260                 if (equal == len)
261                         die("Missing '=': '%s'", buf);
262
263                 fsck_set_msg_type(options, buf, buf + equal + 1);
264                 buf += len + 1;
265         }
266         free(to_free);
267 }
268
269 static void append_msg_id(struct strbuf *sb, const char *msg_id)
270 {
271         for (;;) {
272                 char c = *(msg_id)++;
273
274                 if (!c)
275                         break;
276                 if (c != '_')
277                         strbuf_addch(sb, tolower(c));
278                 else {
279                         assert(*msg_id);
280                         strbuf_addch(sb, *(msg_id)++);
281                 }
282         }
283
284         strbuf_addstr(sb, ": ");
285 }
286
287 __attribute__((format (printf, 4, 5)))
288 static int report(struct fsck_options *options, struct object *object,
289         enum fsck_msg_id id, const char *fmt, ...)
290 {
291         va_list ap;
292         struct strbuf sb = STRBUF_INIT;
293         int msg_type = fsck_msg_type(id, options), result;
294
295         if (msg_type == FSCK_IGNORE)
296                 return 0;
297
298         if (options->skiplist && object &&
299                         oid_array_lookup(options->skiplist, &object->oid) >= 0)
300                 return 0;
301
302         if (msg_type == FSCK_FATAL)
303                 msg_type = FSCK_ERROR;
304         else if (msg_type == FSCK_INFO)
305                 msg_type = FSCK_WARN;
306
307         append_msg_id(&sb, msg_id_info[id].id_string);
308
309         va_start(ap, fmt);
310         strbuf_vaddf(&sb, fmt, ap);
311         result = options->error_func(options, object, msg_type, sb.buf);
312         strbuf_release(&sb);
313         va_end(ap);
314
315         return result;
316 }
317
318 static char *get_object_name(struct fsck_options *options, struct object *obj)
319 {
320         if (!options->object_names)
321                 return NULL;
322         return lookup_decoration(options->object_names, obj);
323 }
324
325 static void put_object_name(struct fsck_options *options, struct object *obj,
326         const char *fmt, ...)
327 {
328         va_list ap;
329         struct strbuf buf = STRBUF_INIT;
330         char *existing;
331
332         if (!options->object_names)
333                 return;
334         existing = lookup_decoration(options->object_names, obj);
335         if (existing)
336                 return;
337         va_start(ap, fmt);
338         strbuf_vaddf(&buf, fmt, ap);
339         add_decoration(options->object_names, obj, strbuf_detach(&buf, NULL));
340         va_end(ap);
341 }
342
343 static const char *describe_object(struct fsck_options *o, struct object *obj)
344 {
345         static struct strbuf buf = STRBUF_INIT;
346         char *name;
347
348         strbuf_reset(&buf);
349         strbuf_addstr(&buf, oid_to_hex(&obj->oid));
350         if (o->object_names && (name = lookup_decoration(o->object_names, obj)))
351                 strbuf_addf(&buf, " (%s)", name);
352
353         return buf.buf;
354 }
355
356 static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
357 {
358         struct tree_desc desc;
359         struct name_entry entry;
360         int res = 0;
361         const char *name;
362
363         if (parse_tree(tree))
364                 return -1;
365
366         name = get_object_name(options, &tree->object);
367         if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
368                 return -1;
369         while (tree_entry_gently(&desc, &entry)) {
370                 struct object *obj;
371                 int result;
372
373                 if (S_ISGITLINK(entry.mode))
374                         continue;
375
376                 if (S_ISDIR(entry.mode)) {
377                         obj = (struct object *)lookup_tree(entry.oid);
378                         if (name && obj)
379                                 put_object_name(options, obj, "%s%s/", name,
380                                         entry.path);
381                         result = options->walk(obj, OBJ_TREE, data, options);
382                 }
383                 else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
384                         obj = (struct object *)lookup_blob(entry.oid);
385                         if (name && obj)
386                                 put_object_name(options, obj, "%s%s", name,
387                                         entry.path);
388                         result = options->walk(obj, OBJ_BLOB, data, options);
389                 }
390                 else {
391                         result = error("in tree %s: entry %s has bad mode %.6o",
392                                         describe_object(options, &tree->object), entry.path, entry.mode);
393                 }
394                 if (result < 0)
395                         return result;
396                 if (!res)
397                         res = result;
398         }
399         return res;
400 }
401
402 static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
403 {
404         int counter = 0, generation = 0, name_prefix_len = 0;
405         struct commit_list *parents;
406         int res;
407         int result;
408         const char *name;
409
410         if (parse_commit(commit))
411                 return -1;
412
413         name = get_object_name(options, &commit->object);
414         if (name)
415                 put_object_name(options, &commit->tree->object, "%s:", name);
416
417         result = options->walk((struct object *)commit->tree, OBJ_TREE, data, options);
418         if (result < 0)
419                 return result;
420         res = result;
421
422         parents = commit->parents;
423         if (name && parents) {
424                 int len = strlen(name), power;
425
426                 if (len && name[len - 1] == '^') {
427                         generation = 1;
428                         name_prefix_len = len - 1;
429                 }
430                 else { /* parse ~<generation> suffix */
431                         for (generation = 0, power = 1;
432                              len && isdigit(name[len - 1]);
433                              power *= 10)
434                                 generation += power * (name[--len] - '0');
435                         if (power > 1 && len && name[len - 1] == '~')
436                                 name_prefix_len = len - 1;
437                 }
438         }
439
440         while (parents) {
441                 if (name) {
442                         struct object *obj = &parents->item->object;
443
444                         if (++counter > 1)
445                                 put_object_name(options, obj, "%s^%d",
446                                         name, counter);
447                         else if (generation > 0)
448                                 put_object_name(options, obj, "%.*s~%d",
449                                         name_prefix_len, name, generation + 1);
450                         else
451                                 put_object_name(options, obj, "%s^", name);
452                 }
453                 result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
454                 if (result < 0)
455                         return result;
456                 if (!res)
457                         res = result;
458                 parents = parents->next;
459         }
460         return res;
461 }
462
463 static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
464 {
465         char *name = get_object_name(options, &tag->object);
466
467         if (parse_tag(tag))
468                 return -1;
469         if (name)
470                 put_object_name(options, tag->tagged, "%s", name);
471         return options->walk(tag->tagged, OBJ_ANY, data, options);
472 }
473
474 int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
475 {
476         if (!obj)
477                 return -1;
478
479         if (obj->type == OBJ_NONE)
480                 parse_object(&obj->oid);
481
482         switch (obj->type) {
483         case OBJ_BLOB:
484                 return 0;
485         case OBJ_TREE:
486                 return fsck_walk_tree((struct tree *)obj, data, options);
487         case OBJ_COMMIT:
488                 return fsck_walk_commit((struct commit *)obj, data, options);
489         case OBJ_TAG:
490                 return fsck_walk_tag((struct tag *)obj, data, options);
491         default:
492                 error("Unknown object type for %s", describe_object(options, obj));
493                 return -1;
494         }
495 }
496
497 /*
498  * The entries in a tree are ordered in the _path_ order,
499  * which means that a directory entry is ordered by adding
500  * a slash to the end of it.
501  *
502  * So a directory called "a" is ordered _after_ a file
503  * called "a.c", because "a/" sorts after "a.c".
504  */
505 #define TREE_UNORDERED (-1)
506 #define TREE_HAS_DUPS  (-2)
507
508 static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
509 {
510         int len1 = strlen(name1);
511         int len2 = strlen(name2);
512         int len = len1 < len2 ? len1 : len2;
513         unsigned char c1, c2;
514         int cmp;
515
516         cmp = memcmp(name1, name2, len);
517         if (cmp < 0)
518                 return 0;
519         if (cmp > 0)
520                 return TREE_UNORDERED;
521
522         /*
523          * Ok, the first <len> characters are the same.
524          * Now we need to order the next one, but turn
525          * a '\0' into a '/' for a directory entry.
526          */
527         c1 = name1[len];
528         c2 = name2[len];
529         if (!c1 && !c2)
530                 /*
531                  * git-write-tree used to write out a nonsense tree that has
532                  * entries with the same name, one blob and one tree.  Make
533                  * sure we do not have duplicate entries.
534                  */
535                 return TREE_HAS_DUPS;
536         if (!c1 && S_ISDIR(mode1))
537                 c1 = '/';
538         if (!c2 && S_ISDIR(mode2))
539                 c2 = '/';
540         return c1 < c2 ? 0 : TREE_UNORDERED;
541 }
542
543 static int fsck_tree(struct tree *item, struct fsck_options *options)
544 {
545         int retval = 0;
546         int has_null_sha1 = 0;
547         int has_full_path = 0;
548         int has_empty_name = 0;
549         int has_dot = 0;
550         int has_dotdot = 0;
551         int has_dotgit = 0;
552         int has_zero_pad = 0;
553         int has_bad_modes = 0;
554         int has_dup_entries = 0;
555         int not_properly_sorted = 0;
556         struct tree_desc desc;
557         unsigned o_mode;
558         const char *o_name;
559
560         if (init_tree_desc_gently(&desc, item->buffer, item->size)) {
561                 retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
562                 return retval;
563         }
564
565         o_mode = 0;
566         o_name = NULL;
567
568         while (desc.size) {
569                 unsigned mode;
570                 const char *name, *backslash;
571                 const struct object_id *oid;
572
573                 oid = tree_entry_extract(&desc, &name, &mode);
574
575                 has_null_sha1 |= is_null_oid(oid);
576                 has_full_path |= !!strchr(name, '/');
577                 has_empty_name |= !*name;
578                 has_dot |= !strcmp(name, ".");
579                 has_dotdot |= !strcmp(name, "..");
580                 has_dotgit |= is_hfs_dotgit(name) || is_ntfs_dotgit(name);
581                 has_zero_pad |= *(char *)desc.buffer == '0';
582
583                 if (is_hfs_dotgitmodules(name) || is_ntfs_dotgitmodules(name)) {
584                         if (!S_ISLNK(mode))
585                                 oidset_insert(&gitmodules_found, oid);
586                         else
587                                 retval += report(options, &item->object,
588                                                  FSCK_MSG_GITMODULES_SYMLINK,
589                                                  ".gitmodules is a symbolic link");
590                 }
591
592                 if ((backslash = strchr(name, '\\'))) {
593                         while (backslash) {
594                                 backslash++;
595                                 has_dotgit |= is_ntfs_dotgit(backslash);
596                                 if (is_ntfs_dotgitmodules(backslash)) {
597                                         if (!S_ISLNK(mode))
598                                                 oidset_insert(&gitmodules_found, oid);
599                                         else
600                                                 retval += report(options, &item->object,
601                                                                  FSCK_MSG_GITMODULES_SYMLINK,
602                                                                  ".gitmodules is a symbolic link");
603                                 }
604                                 backslash = strchr(backslash, '\\');
605                         }
606                 }
607
608                 if (update_tree_entry_gently(&desc)) {
609                         retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
610                         break;
611                 }
612
613                 switch (mode) {
614                 /*
615                  * Standard modes..
616                  */
617                 case S_IFREG | 0755:
618                 case S_IFREG | 0644:
619                 case S_IFLNK:
620                 case S_IFDIR:
621                 case S_IFGITLINK:
622                         break;
623                 /*
624                  * This is nonstandard, but we had a few of these
625                  * early on when we honored the full set of mode
626                  * bits..
627                  */
628                 case S_IFREG | 0664:
629                         if (!options->strict)
630                                 break;
631                         /* fallthrough */
632                 default:
633                         has_bad_modes = 1;
634                 }
635
636                 if (o_name) {
637                         switch (verify_ordered(o_mode, o_name, mode, name)) {
638                         case TREE_UNORDERED:
639                                 not_properly_sorted = 1;
640                                 break;
641                         case TREE_HAS_DUPS:
642                                 has_dup_entries = 1;
643                                 break;
644                         default:
645                                 break;
646                         }
647                 }
648
649                 o_mode = mode;
650                 o_name = name;
651         }
652
653         if (has_null_sha1)
654                 retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
655         if (has_full_path)
656                 retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
657         if (has_empty_name)
658                 retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
659         if (has_dot)
660                 retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
661         if (has_dotdot)
662                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
663         if (has_dotgit)
664                 retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
665         if (has_zero_pad)
666                 retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
667         if (has_bad_modes)
668                 retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
669         if (has_dup_entries)
670                 retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
671         if (not_properly_sorted)
672                 retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
673         return retval;
674 }
675
676 static int verify_headers(const void *data, unsigned long size,
677                           struct object *obj, struct fsck_options *options)
678 {
679         const char *buffer = (const char *)data;
680         unsigned long i;
681
682         for (i = 0; i < size; i++) {
683                 switch (buffer[i]) {
684                 case '\0':
685                         return report(options, obj,
686                                 FSCK_MSG_NUL_IN_HEADER,
687                                 "unterminated header: NUL at offset %ld", i);
688                 case '\n':
689                         if (i + 1 < size && buffer[i + 1] == '\n')
690                                 return 0;
691                 }
692         }
693
694         /*
695          * We did not find double-LF that separates the header
696          * and the body.  Not having a body is not a crime but
697          * we do want to see the terminating LF for the last header
698          * line.
699          */
700         if (size && buffer[size - 1] == '\n')
701                 return 0;
702
703         return report(options, obj,
704                 FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
705 }
706
707 static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
708 {
709         const char *p = *ident;
710         char *end;
711
712         *ident = strchrnul(*ident, '\n');
713         if (**ident == '\n')
714                 (*ident)++;
715
716         if (*p == '<')
717                 return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
718         p += strcspn(p, "<>\n");
719         if (*p == '>')
720                 return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
721         if (*p != '<')
722                 return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
723         if (p[-1] != ' ')
724                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
725         p++;
726         p += strcspn(p, "<>\n");
727         if (*p != '>')
728                 return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
729         p++;
730         if (*p != ' ')
731                 return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
732         p++;
733         if (*p == '0' && p[1] != ' ')
734                 return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
735         if (date_overflows(parse_timestamp(p, &end, 10)))
736                 return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
737         if ((end == p || *end != ' '))
738                 return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
739         p = end + 1;
740         if ((*p != '+' && *p != '-') ||
741             !isdigit(p[1]) ||
742             !isdigit(p[2]) ||
743             !isdigit(p[3]) ||
744             !isdigit(p[4]) ||
745             (p[5] != '\n'))
746                 return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
747         p += 6;
748         return 0;
749 }
750
751 static int fsck_commit_buffer(struct commit *commit, const char *buffer,
752         unsigned long size, struct fsck_options *options)
753 {
754         unsigned char tree_sha1[20], sha1[20];
755         struct commit_graft *graft;
756         unsigned parent_count, parent_line_count = 0, author_count;
757         int err;
758         const char *buffer_begin = buffer;
759
760         if (verify_headers(buffer, size, &commit->object, options))
761                 return -1;
762
763         if (!skip_prefix(buffer, "tree ", &buffer))
764                 return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
765         if (get_sha1_hex(buffer, tree_sha1) || buffer[40] != '\n') {
766                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
767                 if (err)
768                         return err;
769         }
770         buffer += 41;
771         while (skip_prefix(buffer, "parent ", &buffer)) {
772                 if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n') {
773                         err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
774                         if (err)
775                                 return err;
776                 }
777                 buffer += 41;
778                 parent_line_count++;
779         }
780         graft = lookup_commit_graft(&commit->object.oid);
781         parent_count = commit_list_count(commit->parents);
782         if (graft) {
783                 if (graft->nr_parent == -1 && !parent_count)
784                         ; /* shallow commit */
785                 else if (graft->nr_parent != parent_count) {
786                         err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
787                         if (err)
788                                 return err;
789                 }
790         } else {
791                 if (parent_count != parent_line_count) {
792                         err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
793                         if (err)
794                                 return err;
795                 }
796         }
797         author_count = 0;
798         while (skip_prefix(buffer, "author ", &buffer)) {
799                 author_count++;
800                 err = fsck_ident(&buffer, &commit->object, options);
801                 if (err)
802                         return err;
803         }
804         if (author_count < 1)
805                 err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
806         else if (author_count > 1)
807                 err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
808         if (err)
809                 return err;
810         if (!skip_prefix(buffer, "committer ", &buffer))
811                 return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
812         err = fsck_ident(&buffer, &commit->object, options);
813         if (err)
814                 return err;
815         if (!commit->tree) {
816                 err = report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", sha1_to_hex(tree_sha1));
817                 if (err)
818                         return err;
819         }
820         if (memchr(buffer_begin, '\0', size)) {
821                 err = report(options, &commit->object, FSCK_MSG_NUL_IN_COMMIT,
822                              "NUL byte in the commit object body");
823                 if (err)
824                         return err;
825         }
826         return 0;
827 }
828
829 static int fsck_commit(struct commit *commit, const char *data,
830         unsigned long size, struct fsck_options *options)
831 {
832         const char *buffer = data ?  data : get_commit_buffer(commit, &size);
833         int ret = fsck_commit_buffer(commit, buffer, size, options);
834         if (!data)
835                 unuse_commit_buffer(commit, buffer);
836         return ret;
837 }
838
839 static int fsck_tag_buffer(struct tag *tag, const char *data,
840         unsigned long size, struct fsck_options *options)
841 {
842         unsigned char sha1[20];
843         int ret = 0;
844         const char *buffer;
845         char *to_free = NULL, *eol;
846         struct strbuf sb = STRBUF_INIT;
847
848         if (data)
849                 buffer = data;
850         else {
851                 enum object_type type;
852
853                 buffer = to_free =
854                         read_sha1_file(tag->object.oid.hash, &type, &size);
855                 if (!buffer)
856                         return report(options, &tag->object,
857                                 FSCK_MSG_MISSING_TAG_OBJECT,
858                                 "cannot read tag object");
859
860                 if (type != OBJ_TAG) {
861                         ret = report(options, &tag->object,
862                                 FSCK_MSG_TAG_OBJECT_NOT_TAG,
863                                 "expected tag got %s",
864                             type_name(type));
865                         goto done;
866                 }
867         }
868
869         ret = verify_headers(buffer, size, &tag->object, options);
870         if (ret)
871                 goto done;
872
873         if (!skip_prefix(buffer, "object ", &buffer)) {
874                 ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
875                 goto done;
876         }
877         if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n') {
878                 ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
879                 if (ret)
880                         goto done;
881         }
882         buffer += 41;
883
884         if (!skip_prefix(buffer, "type ", &buffer)) {
885                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
886                 goto done;
887         }
888         eol = strchr(buffer, '\n');
889         if (!eol) {
890                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
891                 goto done;
892         }
893         if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
894                 ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
895         if (ret)
896                 goto done;
897         buffer = eol + 1;
898
899         if (!skip_prefix(buffer, "tag ", &buffer)) {
900                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
901                 goto done;
902         }
903         eol = strchr(buffer, '\n');
904         if (!eol) {
905                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
906                 goto done;
907         }
908         strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
909         if (check_refname_format(sb.buf, 0)) {
910                 ret = report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
911                            "invalid 'tag' name: %.*s",
912                            (int)(eol - buffer), buffer);
913                 if (ret)
914                         goto done;
915         }
916         buffer = eol + 1;
917
918         if (!skip_prefix(buffer, "tagger ", &buffer)) {
919                 /* early tags do not contain 'tagger' lines; warn only */
920                 ret = report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
921                 if (ret)
922                         goto done;
923         }
924         else
925                 ret = fsck_ident(&buffer, &tag->object, options);
926
927 done:
928         strbuf_release(&sb);
929         free(to_free);
930         return ret;
931 }
932
933 static int fsck_tag(struct tag *tag, const char *data,
934         unsigned long size, struct fsck_options *options)
935 {
936         struct object *tagged = tag->tagged;
937
938         if (!tagged)
939                 return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
940
941         return fsck_tag_buffer(tag, data, size, options);
942 }
943
944 struct fsck_gitmodules_data {
945         struct object *obj;
946         struct fsck_options *options;
947         int ret;
948 };
949
950 static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
951 {
952         struct fsck_gitmodules_data *data = vdata;
953         const char *subsection, *key;
954         int subsection_len;
955         char *name;
956
957         if (parse_config_key(var, "submodule", &subsection, &subsection_len, &key) < 0 ||
958             !subsection)
959                 return 0;
960
961         name = xmemdupz(subsection, subsection_len);
962         if (check_submodule_name(name) < 0)
963                 data->ret |= report(data->options, data->obj,
964                                     FSCK_MSG_GITMODULES_NAME,
965                                     "disallowed submodule name: %s",
966                                     name);
967         if (!strcmp(key, "url") && value &&
968             looks_like_command_line_option(value))
969                 data->ret |= report(data->options, data->obj,
970                                     FSCK_MSG_GITMODULES_URL,
971                                     "disallowed submodule url: %s",
972                                     value);
973         if (!strcmp(key, "path") && value &&
974             looks_like_command_line_option(value))
975                 data->ret |= report(data->options, data->obj,
976                                     FSCK_MSG_GITMODULES_PATH,
977                                     "disallowed submodule path: %s",
978                                     value);
979         if (!strcmp(key, "update") && value &&
980             parse_submodule_update_type(value) == SM_UPDATE_COMMAND)
981                 data->ret |= report(data->options, data->obj,
982                                     FSCK_MSG_GITMODULES_UPDATE,
983                                     "disallowed submodule update setting: %s",
984                                     value);
985         free(name);
986
987         return 0;
988 }
989
990 static int fsck_blob(struct blob *blob, const char *buf,
991                      unsigned long size, struct fsck_options *options)
992 {
993         struct fsck_gitmodules_data data;
994
995         if (!oidset_contains(&gitmodules_found, &blob->object.oid))
996                 return 0;
997         oidset_insert(&gitmodules_done, &blob->object.oid);
998
999         if (!buf) {
1000                 /*
1001                  * A missing buffer here is a sign that the caller found the
1002                  * blob too gigantic to load into memory. Let's just consider
1003                  * that an error.
1004                  */
1005                 return report(options, &blob->object,
1006                               FSCK_MSG_GITMODULES_PARSE,
1007                               ".gitmodules too large to parse");
1008         }
1009
1010         data.obj = &blob->object;
1011         data.options = options;
1012         data.ret = 0;
1013         if (git_config_from_mem(fsck_gitmodules_fn, CONFIG_ORIGIN_BLOB,
1014                                 ".gitmodules", buf, size, &data))
1015                 data.ret |= report(options, &blob->object,
1016                                    FSCK_MSG_GITMODULES_PARSE,
1017                                    "could not parse gitmodules blob");
1018
1019         return data.ret;
1020 }
1021
1022 int fsck_object(struct object *obj, void *data, unsigned long size,
1023         struct fsck_options *options)
1024 {
1025         if (!obj)
1026                 return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
1027
1028         if (obj->type == OBJ_BLOB)
1029                 return fsck_blob((struct blob *)obj, data, size, options);
1030         if (obj->type == OBJ_TREE)
1031                 return fsck_tree((struct tree *) obj, options);
1032         if (obj->type == OBJ_COMMIT)
1033                 return fsck_commit((struct commit *) obj, (const char *) data,
1034                         size, options);
1035         if (obj->type == OBJ_TAG)
1036                 return fsck_tag((struct tag *) obj, (const char *) data,
1037                         size, options);
1038
1039         return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
1040                           obj->type);
1041 }
1042
1043 int fsck_error_function(struct fsck_options *o,
1044         struct object *obj, int msg_type, const char *message)
1045 {
1046         if (msg_type == FSCK_WARN) {
1047                 warning("object %s: %s", describe_object(o, obj), message);
1048                 return 0;
1049         }
1050         error("object %s: %s", describe_object(o, obj), message);
1051         return 1;
1052 }
1053
1054 int fsck_finish(struct fsck_options *options)
1055 {
1056         int ret = 0;
1057         struct oidset_iter iter;
1058         const struct object_id *oid;
1059
1060         oidset_iter_init(&gitmodules_found, &iter);
1061         while ((oid = oidset_iter_next(&iter))) {
1062                 struct blob *blob;
1063                 enum object_type type;
1064                 unsigned long size;
1065                 char *buf;
1066
1067                 if (oidset_contains(&gitmodules_done, oid))
1068                         continue;
1069
1070                 blob = lookup_blob(oid);
1071                 if (!blob) {
1072                         ret |= report(options, &blob->object,
1073                                       FSCK_MSG_GITMODULES_BLOB,
1074                                       "non-blob found at .gitmodules");
1075                         continue;
1076                 }
1077
1078                 buf = read_sha1_file(oid->hash, &type, &size);
1079                 if (!buf) {
1080                         if (is_promisor_object(&blob->object.oid))
1081                                 continue;
1082                         ret |= report(options, &blob->object,
1083                                       FSCK_MSG_GITMODULES_MISSING,
1084                                       "unable to read .gitmodules blob");
1085                         continue;
1086                 }
1087
1088                 if (type == OBJ_BLOB)
1089                         ret |= fsck_blob(blob, buf, size, options);
1090                 else
1091                         ret |= report(options, &blob->object,
1092                                       FSCK_MSG_GITMODULES_BLOB,
1093                                       "non-blob found at .gitmodules");
1094                 free(buf);
1095         }
1096
1097
1098         oidset_clear(&gitmodules_found);
1099         oidset_clear(&gitmodules_done);
1100         return ret;
1101 }