ab246185e8f0d80e218b61fd88b74469cbb3f9ea
   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
  12#define FOREACH_MSG_ID(FUNC) \
  13        /* errors */ \
  14        FUNC(BAD_DATE, ERROR) \
  15        FUNC(BAD_DATE_OVERFLOW, ERROR) \
  16        FUNC(BAD_EMAIL, ERROR) \
  17        FUNC(BAD_NAME, ERROR) \
  18        FUNC(BAD_OBJECT_SHA1, ERROR) \
  19        FUNC(BAD_PARENT_SHA1, ERROR) \
  20        FUNC(BAD_TAG_OBJECT, ERROR) \
  21        FUNC(BAD_TIMEZONE, ERROR) \
  22        FUNC(BAD_TREE, ERROR) \
  23        FUNC(BAD_TREE_SHA1, ERROR) \
  24        FUNC(BAD_TYPE, ERROR) \
  25        FUNC(DUPLICATE_ENTRIES, ERROR) \
  26        FUNC(MISSING_AUTHOR, ERROR) \
  27        FUNC(MISSING_COMMITTER, ERROR) \
  28        FUNC(MISSING_EMAIL, ERROR) \
  29        FUNC(MISSING_GRAFT, ERROR) \
  30        FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
  31        FUNC(MISSING_OBJECT, ERROR) \
  32        FUNC(MISSING_PARENT, ERROR) \
  33        FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
  34        FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
  35        FUNC(MISSING_TAG, ERROR) \
  36        FUNC(MISSING_TAG_ENTRY, ERROR) \
  37        FUNC(MISSING_TAG_OBJECT, ERROR) \
  38        FUNC(MISSING_TREE, ERROR) \
  39        FUNC(MISSING_TYPE, ERROR) \
  40        FUNC(MISSING_TYPE_ENTRY, ERROR) \
  41        FUNC(NUL_IN_HEADER, ERROR) \
  42        FUNC(TAG_OBJECT_NOT_TAG, ERROR) \
  43        FUNC(TREE_NOT_SORTED, ERROR) \
  44        FUNC(UNKNOWN_TYPE, ERROR) \
  45        FUNC(UNTERMINATED_HEADER, ERROR) \
  46        FUNC(ZERO_PADDED_DATE, ERROR) \
  47        /* warnings */ \
  48        FUNC(BAD_FILEMODE, WARN) \
  49        FUNC(BAD_TAG_NAME, WARN) \
  50        FUNC(EMPTY_NAME, WARN) \
  51        FUNC(FULL_PATHNAME, WARN) \
  52        FUNC(HAS_DOT, WARN) \
  53        FUNC(HAS_DOTDOT, WARN) \
  54        FUNC(HAS_DOTGIT, WARN) \
  55        FUNC(MISSING_TAGGER_ENTRY, WARN) \
  56        FUNC(NULL_SHA1, WARN) \
  57        FUNC(ZERO_PADDED_FILEMODE, WARN)
  58
  59#define MSG_ID(id, msg_type) FSCK_MSG_##id,
  60enum fsck_msg_id {
  61        FOREACH_MSG_ID(MSG_ID)
  62        FSCK_MSG_MAX
  63};
  64#undef MSG_ID
  65
  66#define MSG_ID(id, msg_type) { FSCK_##msg_type },
  67static struct {
  68        int msg_type;
  69} msg_id_info[FSCK_MSG_MAX + 1] = {
  70        FOREACH_MSG_ID(MSG_ID)
  71        { -1 }
  72};
  73#undef MSG_ID
  74
  75static int fsck_msg_type(enum fsck_msg_id msg_id,
  76        struct fsck_options *options)
  77{
  78        int msg_type;
  79
  80        msg_type = msg_id_info[msg_id].msg_type;
  81        if (options->strict && msg_type == FSCK_WARN)
  82                msg_type = FSCK_ERROR;
  83
  84        return msg_type;
  85}
  86
  87__attribute__((format (printf, 4, 5)))
  88static int report(struct fsck_options *options, struct object *object,
  89        enum fsck_msg_id id, const char *fmt, ...)
  90{
  91        va_list ap;
  92        struct strbuf sb = STRBUF_INIT;
  93        int msg_type = fsck_msg_type(id, options), result;
  94
  95        va_start(ap, fmt);
  96        strbuf_vaddf(&sb, fmt, ap);
  97        result = options->error_func(object, msg_type, sb.buf);
  98        strbuf_release(&sb);
  99        va_end(ap);
 100
 101        return result;
 102}
 103
 104static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
 105{
 106        struct tree_desc desc;
 107        struct name_entry entry;
 108        int res = 0;
 109
 110        if (parse_tree(tree))
 111                return -1;
 112
 113        init_tree_desc(&desc, tree->buffer, tree->size);
 114        while (tree_entry(&desc, &entry)) {
 115                int result;
 116
 117                if (S_ISGITLINK(entry.mode))
 118                        continue;
 119                if (S_ISDIR(entry.mode))
 120                        result = options->walk(&lookup_tree(entry.sha1)->object, OBJ_TREE, data, options);
 121                else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode))
 122                        result = options->walk(&lookup_blob(entry.sha1)->object, OBJ_BLOB, data, options);
 123                else {
 124                        result = error("in tree %s: entry %s has bad mode %.6o",
 125                                        sha1_to_hex(tree->object.sha1), entry.path, entry.mode);
 126                }
 127                if (result < 0)
 128                        return result;
 129                if (!res)
 130                        res = result;
 131        }
 132        return res;
 133}
 134
 135static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
 136{
 137        struct commit_list *parents;
 138        int res;
 139        int result;
 140
 141        if (parse_commit(commit))
 142                return -1;
 143
 144        result = options->walk((struct object *)commit->tree, OBJ_TREE, data, options);
 145        if (result < 0)
 146                return result;
 147        res = result;
 148
 149        parents = commit->parents;
 150        while (parents) {
 151                result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
 152                if (result < 0)
 153                        return result;
 154                if (!res)
 155                        res = result;
 156                parents = parents->next;
 157        }
 158        return res;
 159}
 160
 161static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
 162{
 163        if (parse_tag(tag))
 164                return -1;
 165        return options->walk(tag->tagged, OBJ_ANY, data, options);
 166}
 167
 168int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
 169{
 170        if (!obj)
 171                return -1;
 172        switch (obj->type) {
 173        case OBJ_BLOB:
 174                return 0;
 175        case OBJ_TREE:
 176                return fsck_walk_tree((struct tree *)obj, data, options);
 177        case OBJ_COMMIT:
 178                return fsck_walk_commit((struct commit *)obj, data, options);
 179        case OBJ_TAG:
 180                return fsck_walk_tag((struct tag *)obj, data, options);
 181        default:
 182                error("Unknown object type for %s", sha1_to_hex(obj->sha1));
 183                return -1;
 184        }
 185}
 186
 187/*
 188 * The entries in a tree are ordered in the _path_ order,
 189 * which means that a directory entry is ordered by adding
 190 * a slash to the end of it.
 191 *
 192 * So a directory called "a" is ordered _after_ a file
 193 * called "a.c", because "a/" sorts after "a.c".
 194 */
 195#define TREE_UNORDERED (-1)
 196#define TREE_HAS_DUPS  (-2)
 197
 198static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
 199{
 200        int len1 = strlen(name1);
 201        int len2 = strlen(name2);
 202        int len = len1 < len2 ? len1 : len2;
 203        unsigned char c1, c2;
 204        int cmp;
 205
 206        cmp = memcmp(name1, name2, len);
 207        if (cmp < 0)
 208                return 0;
 209        if (cmp > 0)
 210                return TREE_UNORDERED;
 211
 212        /*
 213         * Ok, the first <len> characters are the same.
 214         * Now we need to order the next one, but turn
 215         * a '\0' into a '/' for a directory entry.
 216         */
 217        c1 = name1[len];
 218        c2 = name2[len];
 219        if (!c1 && !c2)
 220                /*
 221                 * git-write-tree used to write out a nonsense tree that has
 222                 * entries with the same name, one blob and one tree.  Make
 223                 * sure we do not have duplicate entries.
 224                 */
 225                return TREE_HAS_DUPS;
 226        if (!c1 && S_ISDIR(mode1))
 227                c1 = '/';
 228        if (!c2 && S_ISDIR(mode2))
 229                c2 = '/';
 230        return c1 < c2 ? 0 : TREE_UNORDERED;
 231}
 232
 233static int fsck_tree(struct tree *item, struct fsck_options *options)
 234{
 235        int retval;
 236        int has_null_sha1 = 0;
 237        int has_full_path = 0;
 238        int has_empty_name = 0;
 239        int has_dot = 0;
 240        int has_dotdot = 0;
 241        int has_dotgit = 0;
 242        int has_zero_pad = 0;
 243        int has_bad_modes = 0;
 244        int has_dup_entries = 0;
 245        int not_properly_sorted = 0;
 246        struct tree_desc desc;
 247        unsigned o_mode;
 248        const char *o_name;
 249
 250        init_tree_desc(&desc, item->buffer, item->size);
 251
 252        o_mode = 0;
 253        o_name = NULL;
 254
 255        while (desc.size) {
 256                unsigned mode;
 257                const char *name;
 258                const unsigned char *sha1;
 259
 260                sha1 = tree_entry_extract(&desc, &name, &mode);
 261
 262                has_null_sha1 |= is_null_sha1(sha1);
 263                has_full_path |= !!strchr(name, '/');
 264                has_empty_name |= !*name;
 265                has_dot |= !strcmp(name, ".");
 266                has_dotdot |= !strcmp(name, "..");
 267                has_dotgit |= (!strcmp(name, ".git") ||
 268                               is_hfs_dotgit(name) ||
 269                               is_ntfs_dotgit(name));
 270                has_zero_pad |= *(char *)desc.buffer == '0';
 271                update_tree_entry(&desc);
 272
 273                switch (mode) {
 274                /*
 275                 * Standard modes..
 276                 */
 277                case S_IFREG | 0755:
 278                case S_IFREG | 0644:
 279                case S_IFLNK:
 280                case S_IFDIR:
 281                case S_IFGITLINK:
 282                        break;
 283                /*
 284                 * This is nonstandard, but we had a few of these
 285                 * early on when we honored the full set of mode
 286                 * bits..
 287                 */
 288                case S_IFREG | 0664:
 289                        if (!options->strict)
 290                                break;
 291                default:
 292                        has_bad_modes = 1;
 293                }
 294
 295                if (o_name) {
 296                        switch (verify_ordered(o_mode, o_name, mode, name)) {
 297                        case TREE_UNORDERED:
 298                                not_properly_sorted = 1;
 299                                break;
 300                        case TREE_HAS_DUPS:
 301                                has_dup_entries = 1;
 302                                break;
 303                        default:
 304                                break;
 305                        }
 306                }
 307
 308                o_mode = mode;
 309                o_name = name;
 310        }
 311
 312        retval = 0;
 313        if (has_null_sha1)
 314                retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
 315        if (has_full_path)
 316                retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
 317        if (has_empty_name)
 318                retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
 319        if (has_dot)
 320                retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
 321        if (has_dotdot)
 322                retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
 323        if (has_dotgit)
 324                retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
 325        if (has_zero_pad)
 326                retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
 327        if (has_bad_modes)
 328                retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
 329        if (has_dup_entries)
 330                retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
 331        if (not_properly_sorted)
 332                retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
 333        return retval;
 334}
 335
 336static int require_end_of_header(const void *data, unsigned long size,
 337        struct object *obj, struct fsck_options *options)
 338{
 339        const char *buffer = (const char *)data;
 340        unsigned long i;
 341
 342        for (i = 0; i < size; i++) {
 343                switch (buffer[i]) {
 344                case '\0':
 345                        return report(options, obj,
 346                                FSCK_MSG_NUL_IN_HEADER,
 347                                "unterminated header: NUL at offset %ld", i);
 348                case '\n':
 349                        if (i + 1 < size && buffer[i + 1] == '\n')
 350                                return 0;
 351                }
 352        }
 353
 354        return report(options, obj,
 355                FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
 356}
 357
 358static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
 359{
 360        char *end;
 361
 362        if (**ident == '<')
 363                return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 364        *ident += strcspn(*ident, "<>\n");
 365        if (**ident == '>')
 366                return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
 367        if (**ident != '<')
 368                return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
 369        if ((*ident)[-1] != ' ')
 370                return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 371        (*ident)++;
 372        *ident += strcspn(*ident, "<>\n");
 373        if (**ident != '>')
 374                return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
 375        (*ident)++;
 376        if (**ident != ' ')
 377                return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
 378        (*ident)++;
 379        if (**ident == '0' && (*ident)[1] != ' ')
 380                return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
 381        if (date_overflows(strtoul(*ident, &end, 10)))
 382                return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
 383        if (end == *ident || *end != ' ')
 384                return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
 385        *ident = end + 1;
 386        if ((**ident != '+' && **ident != '-') ||
 387            !isdigit((*ident)[1]) ||
 388            !isdigit((*ident)[2]) ||
 389            !isdigit((*ident)[3]) ||
 390            !isdigit((*ident)[4]) ||
 391            ((*ident)[5] != '\n'))
 392                return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
 393        (*ident) += 6;
 394        return 0;
 395}
 396
 397static int fsck_commit_buffer(struct commit *commit, const char *buffer,
 398        unsigned long size, struct fsck_options *options)
 399{
 400        unsigned char tree_sha1[20], sha1[20];
 401        struct commit_graft *graft;
 402        unsigned parent_count, parent_line_count = 0;
 403        int err;
 404
 405        if (require_end_of_header(buffer, size, &commit->object, options))
 406                return -1;
 407
 408        if (!skip_prefix(buffer, "tree ", &buffer))
 409                return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
 410        if (get_sha1_hex(buffer, tree_sha1) || buffer[40] != '\n')
 411                return report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
 412        buffer += 41;
 413        while (skip_prefix(buffer, "parent ", &buffer)) {
 414                if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n')
 415                        return report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
 416                buffer += 41;
 417                parent_line_count++;
 418        }
 419        graft = lookup_commit_graft(commit->object.sha1);
 420        parent_count = commit_list_count(commit->parents);
 421        if (graft) {
 422                if (graft->nr_parent == -1 && !parent_count)
 423                        ; /* shallow commit */
 424                else if (graft->nr_parent != parent_count)
 425                        return report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
 426        } else {
 427                if (parent_count != parent_line_count)
 428                        return report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
 429        }
 430        if (!skip_prefix(buffer, "author ", &buffer))
 431                return report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
 432        err = fsck_ident(&buffer, &commit->object, options);
 433        if (err)
 434                return err;
 435        if (!skip_prefix(buffer, "committer ", &buffer))
 436                return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
 437        err = fsck_ident(&buffer, &commit->object, options);
 438        if (err)
 439                return err;
 440        if (!commit->tree)
 441                return report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", sha1_to_hex(tree_sha1));
 442
 443        return 0;
 444}
 445
 446static int fsck_commit(struct commit *commit, const char *data,
 447        unsigned long size, struct fsck_options *options)
 448{
 449        const char *buffer = data ?  data : get_commit_buffer(commit, &size);
 450        int ret = fsck_commit_buffer(commit, buffer, size, options);
 451        if (!data)
 452                unuse_commit_buffer(commit, buffer);
 453        return ret;
 454}
 455
 456static int fsck_tag_buffer(struct tag *tag, const char *data,
 457        unsigned long size, struct fsck_options *options)
 458{
 459        unsigned char sha1[20];
 460        int ret = 0;
 461        const char *buffer;
 462        char *to_free = NULL, *eol;
 463        struct strbuf sb = STRBUF_INIT;
 464
 465        if (data)
 466                buffer = data;
 467        else {
 468                enum object_type type;
 469
 470                buffer = to_free =
 471                        read_sha1_file(tag->object.sha1, &type, &size);
 472                if (!buffer)
 473                        return report(options, &tag->object,
 474                                FSCK_MSG_MISSING_TAG_OBJECT,
 475                                "cannot read tag object");
 476
 477                if (type != OBJ_TAG) {
 478                        ret = report(options, &tag->object,
 479                                FSCK_MSG_TAG_OBJECT_NOT_TAG,
 480                                "expected tag got %s",
 481                            typename(type));
 482                        goto done;
 483                }
 484        }
 485
 486        if (require_end_of_header(buffer, size, &tag->object, options))
 487                goto done;
 488
 489        if (!skip_prefix(buffer, "object ", &buffer)) {
 490                ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
 491                goto done;
 492        }
 493        if (get_sha1_hex(buffer, sha1) || buffer[40] != '\n') {
 494                ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
 495                goto done;
 496        }
 497        buffer += 41;
 498
 499        if (!skip_prefix(buffer, "type ", &buffer)) {
 500                ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
 501                goto done;
 502        }
 503        eol = strchr(buffer, '\n');
 504        if (!eol) {
 505                ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
 506                goto done;
 507        }
 508        if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
 509                ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
 510        if (ret)
 511                goto done;
 512        buffer = eol + 1;
 513
 514        if (!skip_prefix(buffer, "tag ", &buffer)) {
 515                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
 516                goto done;
 517        }
 518        eol = strchr(buffer, '\n');
 519        if (!eol) {
 520                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
 521                goto done;
 522        }
 523        strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
 524        if (check_refname_format(sb.buf, 0))
 525                report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
 526                           "invalid 'tag' name: %.*s",
 527                           (int)(eol - buffer), buffer);
 528        buffer = eol + 1;
 529
 530        if (!skip_prefix(buffer, "tagger ", &buffer))
 531                /* early tags do not contain 'tagger' lines; warn only */
 532                report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
 533        else
 534                ret = fsck_ident(&buffer, &tag->object, options);
 535
 536done:
 537        strbuf_release(&sb);
 538        free(to_free);
 539        return ret;
 540}
 541
 542static int fsck_tag(struct tag *tag, const char *data,
 543        unsigned long size, struct fsck_options *options)
 544{
 545        struct object *tagged = tag->tagged;
 546
 547        if (!tagged)
 548                return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
 549
 550        return fsck_tag_buffer(tag, data, size, options);
 551}
 552
 553int fsck_object(struct object *obj, void *data, unsigned long size,
 554        struct fsck_options *options)
 555{
 556        if (!obj)
 557                return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
 558
 559        if (obj->type == OBJ_BLOB)
 560                return 0;
 561        if (obj->type == OBJ_TREE)
 562                return fsck_tree((struct tree *) obj, options);
 563        if (obj->type == OBJ_COMMIT)
 564                return fsck_commit((struct commit *) obj, (const char *) data,
 565                        size, options);
 566        if (obj->type == OBJ_TAG)
 567                return fsck_tag((struct tag *) obj, (const char *) data,
 568                        size, options);
 569
 570        return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
 571                          obj->type);
 572}
 573
 574int fsck_error_function(struct object *obj, int msg_type, const char *message)
 575{
 576        error("object %s: %s", sha1_to_hex(obj->sha1), message);
 577        return 1;
 578}