Andrew's git / gitweb.git / fsck.c
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fsck.con commit linear-assignment: fix potential out of bounds memory access (e467a90)
   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 "utf8.h"
  13#include "sha1-array.h"
  14#include "decorate.h"
  15#include "oidset.h"
  16#include "packfile.h"
  17#include "submodule-config.h"
  18#include "config.h"
  19#include "help.h"
  20
  21static struct oidset gitmodules_found = OIDSET_INIT;
  22static struct oidset gitmodules_done = OIDSET_INIT;
  23
  24#define FSCK_FATAL -1
  25#define FSCK_INFO -2
  26
  27#define FOREACH_MSG_ID(FUNC) \
  28        /* fatal errors */ \
  29        FUNC(NUL_IN_HEADER, FATAL) \
  30        FUNC(UNTERMINATED_HEADER, FATAL) \
  31        /* errors */ \
  32        FUNC(BAD_DATE, ERROR) \
  33        FUNC(BAD_DATE_OVERFLOW, ERROR) \
  34        FUNC(BAD_EMAIL, ERROR) \
  35        FUNC(BAD_NAME, ERROR) \
  36        FUNC(BAD_OBJECT_SHA1, ERROR) \
  37        FUNC(BAD_PARENT_SHA1, ERROR) \
  38        FUNC(BAD_TAG_OBJECT, ERROR) \
  39        FUNC(BAD_TIMEZONE, ERROR) \
  40        FUNC(BAD_TREE, ERROR) \
  41        FUNC(BAD_TREE_SHA1, ERROR) \
  42        FUNC(BAD_TYPE, ERROR) \
  43        FUNC(DUPLICATE_ENTRIES, ERROR) \
  44        FUNC(MISSING_AUTHOR, ERROR) \
  45        FUNC(MISSING_COMMITTER, ERROR) \
  46        FUNC(MISSING_EMAIL, ERROR) \
  47        FUNC(MISSING_GRAFT, ERROR) \
  48        FUNC(MISSING_NAME_BEFORE_EMAIL, ERROR) \
  49        FUNC(MISSING_OBJECT, ERROR) \
  50        FUNC(MISSING_PARENT, ERROR) \
  51        FUNC(MISSING_SPACE_BEFORE_DATE, ERROR) \
  52        FUNC(MISSING_SPACE_BEFORE_EMAIL, ERROR) \
  53        FUNC(MISSING_TAG, ERROR) \
  54        FUNC(MISSING_TAG_ENTRY, ERROR) \
  55        FUNC(MISSING_TAG_OBJECT, ERROR) \
  56        FUNC(MISSING_TREE, ERROR) \
  57        FUNC(MISSING_TREE_OBJECT, ERROR) \
  58        FUNC(MISSING_TYPE, ERROR) \
  59        FUNC(MISSING_TYPE_ENTRY, ERROR) \
  60        FUNC(MULTIPLE_AUTHORS, ERROR) \
  61        FUNC(TAG_OBJECT_NOT_TAG, ERROR) \
  62        FUNC(TREE_NOT_SORTED, ERROR) \
  63        FUNC(UNKNOWN_TYPE, ERROR) \
  64        FUNC(ZERO_PADDED_DATE, ERROR) \
  65        FUNC(GITMODULES_MISSING, ERROR) \
  66        FUNC(GITMODULES_BLOB, ERROR) \
  67        FUNC(GITMODULES_LARGE, ERROR) \
  68        FUNC(GITMODULES_NAME, ERROR) \
  69        FUNC(GITMODULES_SYMLINK, 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
  85#define MSG_ID(id, msg_type) FSCK_MSG_##id,
  86enum fsck_msg_id {
  87        FOREACH_MSG_ID(MSG_ID)
  88        FSCK_MSG_MAX
  89};
  90#undef MSG_ID
  91
  92#define STR(x) #x
  93#define MSG_ID(id, msg_type) { STR(id), NULL, NULL, FSCK_##msg_type },
  94static struct {
  95        const char *id_string;
  96        const char *downcased;
  97        const char *camelcased;
  98        int msg_type;
  99} msg_id_info[FSCK_MSG_MAX + 1] = {
 100        FOREACH_MSG_ID(MSG_ID)
 101        { NULL, NULL, NULL, -1 }
 102};
 103#undef MSG_ID
 104
 105static void prepare_msg_ids(void)
 106{
 107        int i;
 108
 109        if (msg_id_info[0].downcased)
 110                return;
 111
 112        /* convert id_string to lower case, without underscores. */
 113        for (i = 0; i < FSCK_MSG_MAX; i++) {
 114                const char *p = msg_id_info[i].id_string;
 115                int len = strlen(p);
 116                char *q = xmalloc(len);
 117
 118                msg_id_info[i].downcased = q;
 119                while (*p)
 120                        if (*p == '_')
 121                                p++;
 122                        else
 123                                *(q)++ = tolower(*(p)++);
 124                *q = '\0';
 125
 126                p = msg_id_info[i].id_string;
 127                q = xmalloc(len);
 128                msg_id_info[i].camelcased = q;
 129                while (*p) {
 130                        if (*p == '_') {
 131                                p++;
 132                                if (*p)
 133                                        *q++ = *p++;
 134                        } else {
 135                                *q++ = tolower(*p++);
 136                        }
 137                }
 138                *q = '\0';
 139        }
 140}
 141
 142static int parse_msg_id(const char *text)
 143{
 144        int i;
 145
 146        prepare_msg_ids();
 147
 148        for (i = 0; i < FSCK_MSG_MAX; i++)
 149                if (!strcmp(text, msg_id_info[i].downcased))
 150                        return i;
 151
 152        return -1;
 153}
 154
 155void list_config_fsck_msg_ids(struct string_list *list, const char *prefix)
 156{
 157        int i;
 158
 159        prepare_msg_ids();
 160
 161        for (i = 0; i < FSCK_MSG_MAX; i++)
 162                list_config_item(list, prefix, msg_id_info[i].camelcased);
 163}
 164
 165static int fsck_msg_type(enum fsck_msg_id msg_id,
 166        struct fsck_options *options)
 167{
 168        int msg_type;
 169
 170        assert(msg_id >= 0 && msg_id < FSCK_MSG_MAX);
 171
 172        if (options->msg_type)
 173                msg_type = options->msg_type[msg_id];
 174        else {
 175                msg_type = msg_id_info[msg_id].msg_type;
 176                if (options->strict && msg_type == FSCK_WARN)
 177                        msg_type = FSCK_ERROR;
 178        }
 179
 180        return msg_type;
 181}
 182
 183static void init_skiplist(struct fsck_options *options, const char *path)
 184{
 185        static struct oid_array skiplist = OID_ARRAY_INIT;
 186        int sorted, fd;
 187        char buffer[GIT_MAX_HEXSZ + 1];
 188        struct object_id oid;
 189
 190        if (options->skiplist)
 191                sorted = options->skiplist->sorted;
 192        else {
 193                sorted = 1;
 194                options->skiplist = &skiplist;
 195        }
 196
 197        fd = open(path, O_RDONLY);
 198        if (fd < 0)
 199                die("Could not open skip list: %s", path);
 200        for (;;) {
 201                const char *p;
 202                int result = read_in_full(fd, buffer, sizeof(buffer));
 203                if (result < 0)
 204                        die_errno("Could not read '%s'", path);
 205                if (!result)
 206                        break;
 207                if (parse_oid_hex(buffer, &oid, &p) || *p != '\n')
 208                        die("Invalid SHA-1: %s", buffer);
 209                oid_array_append(&skiplist, &oid);
 210                if (sorted && skiplist.nr > 1 &&
 211                                oidcmp(&skiplist.oid[skiplist.nr - 2],
 212                                       &oid) > 0)
 213                        sorted = 0;
 214        }
 215        close(fd);
 216
 217        if (sorted)
 218                skiplist.sorted = 1;
 219}
 220
 221static int parse_msg_type(const char *str)
 222{
 223        if (!strcmp(str, "error"))
 224                return FSCK_ERROR;
 225        else if (!strcmp(str, "warn"))
 226                return FSCK_WARN;
 227        else if (!strcmp(str, "ignore"))
 228                return FSCK_IGNORE;
 229        else
 230                die("Unknown fsck message type: '%s'", str);
 231}
 232
 233int is_valid_msg_type(const char *msg_id, const char *msg_type)
 234{
 235        if (parse_msg_id(msg_id) < 0)
 236                return 0;
 237        parse_msg_type(msg_type);
 238        return 1;
 239}
 240
 241void fsck_set_msg_type(struct fsck_options *options,
 242                const char *msg_id, const char *msg_type)
 243{
 244        int id = parse_msg_id(msg_id), type;
 245
 246        if (id < 0)
 247                die("Unhandled message id: %s", msg_id);
 248        type = parse_msg_type(msg_type);
 249
 250        if (type != FSCK_ERROR && msg_id_info[id].msg_type == FSCK_FATAL)
 251                die("Cannot demote %s to %s", msg_id, msg_type);
 252
 253        if (!options->msg_type) {
 254                int i;
 255                int *msg_type;
 256                ALLOC_ARRAY(msg_type, FSCK_MSG_MAX);
 257                for (i = 0; i < FSCK_MSG_MAX; i++)
 258                        msg_type[i] = fsck_msg_type(i, options);
 259                options->msg_type = msg_type;
 260        }
 261
 262        options->msg_type[id] = type;
 263}
 264
 265void fsck_set_msg_types(struct fsck_options *options, const char *values)
 266{
 267        char *buf = xstrdup(values), *to_free = buf;
 268        int done = 0;
 269
 270        while (!done) {
 271                int len = strcspn(buf, " ,|"), equal;
 272
 273                done = !buf[len];
 274                if (!len) {
 275                        buf++;
 276                        continue;
 277                }
 278                buf[len] = '\0';
 279
 280                for (equal = 0;
 281                     equal < len && buf[equal] != '=' && buf[equal] != ':';
 282                     equal++)
 283                        buf[equal] = tolower(buf[equal]);
 284                buf[equal] = '\0';
 285
 286                if (!strcmp(buf, "skiplist")) {
 287                        if (equal == len)
 288                                die("skiplist requires a path");
 289                        init_skiplist(options, buf + equal + 1);
 290                        buf += len + 1;
 291                        continue;
 292                }
 293
 294                if (equal == len)
 295                        die("Missing '=': '%s'", buf);
 296
 297                fsck_set_msg_type(options, buf, buf + equal + 1);
 298                buf += len + 1;
 299        }
 300        free(to_free);
 301}
 302
 303static void append_msg_id(struct strbuf *sb, const char *msg_id)
 304{
 305        for (;;) {
 306                char c = *(msg_id)++;
 307
 308                if (!c)
 309                        break;
 310                if (c != '_')
 311                        strbuf_addch(sb, tolower(c));
 312                else {
 313                        assert(*msg_id);
 314                        strbuf_addch(sb, *(msg_id)++);
 315                }
 316        }
 317
 318        strbuf_addstr(sb, ": ");
 319}
 320
 321static int object_on_skiplist(struct fsck_options *opts, struct object *obj)
 322{
 323        if (opts && opts->skiplist && obj)
 324                return oid_array_lookup(opts->skiplist, &obj->oid) >= 0;
 325        return 0;
 326}
 327
 328__attribute__((format (printf, 4, 5)))
 329static int report(struct fsck_options *options, struct object *object,
 330        enum fsck_msg_id id, const char *fmt, ...)
 331{
 332        va_list ap;
 333        struct strbuf sb = STRBUF_INIT;
 334        int msg_type = fsck_msg_type(id, options), result;
 335
 336        if (msg_type == FSCK_IGNORE)
 337                return 0;
 338
 339        if (object_on_skiplist(options, object))
 340                return 0;
 341
 342        if (msg_type == FSCK_FATAL)
 343                msg_type = FSCK_ERROR;
 344        else if (msg_type == FSCK_INFO)
 345                msg_type = FSCK_WARN;
 346
 347        append_msg_id(&sb, msg_id_info[id].id_string);
 348
 349        va_start(ap, fmt);
 350        strbuf_vaddf(&sb, fmt, ap);
 351        result = options->error_func(options, object, msg_type, sb.buf);
 352        strbuf_release(&sb);
 353        va_end(ap);
 354
 355        return result;
 356}
 357
 358static char *get_object_name(struct fsck_options *options, struct object *obj)
 359{
 360        if (!options->object_names)
 361                return NULL;
 362        return lookup_decoration(options->object_names, obj);
 363}
 364
 365static void put_object_name(struct fsck_options *options, struct object *obj,
 366        const char *fmt, ...)
 367{
 368        va_list ap;
 369        struct strbuf buf = STRBUF_INIT;
 370        char *existing;
 371
 372        if (!options->object_names)
 373                return;
 374        existing = lookup_decoration(options->object_names, obj);
 375        if (existing)
 376                return;
 377        va_start(ap, fmt);
 378        strbuf_vaddf(&buf, fmt, ap);
 379        add_decoration(options->object_names, obj, strbuf_detach(&buf, NULL));
 380        va_end(ap);
 381}
 382
 383static const char *describe_object(struct fsck_options *o, struct object *obj)
 384{
 385        static struct strbuf buf = STRBUF_INIT;
 386        char *name;
 387
 388        strbuf_reset(&buf);
 389        strbuf_addstr(&buf, oid_to_hex(&obj->oid));
 390        if (o->object_names && (name = lookup_decoration(o->object_names, obj)))
 391                strbuf_addf(&buf, " (%s)", name);
 392
 393        return buf.buf;
 394}
 395
 396static int fsck_walk_tree(struct tree *tree, void *data, struct fsck_options *options)
 397{
 398        struct tree_desc desc;
 399        struct name_entry entry;
 400        int res = 0;
 401        const char *name;
 402
 403        if (parse_tree(tree))
 404                return -1;
 405
 406        name = get_object_name(options, &tree->object);
 407        if (init_tree_desc_gently(&desc, tree->buffer, tree->size))
 408                return -1;
 409        while (tree_entry_gently(&desc, &entry)) {
 410                struct object *obj;
 411                int result;
 412
 413                if (S_ISGITLINK(entry.mode))
 414                        continue;
 415
 416                if (S_ISDIR(entry.mode)) {
 417                        obj = (struct object *)lookup_tree(the_repository, entry.oid);
 418                        if (name && obj)
 419                                put_object_name(options, obj, "%s%s/", name,
 420                                        entry.path);
 421                        result = options->walk(obj, OBJ_TREE, data, options);
 422                }
 423                else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode)) {
 424                        obj = (struct object *)lookup_blob(the_repository, entry.oid);
 425                        if (name && obj)
 426                                put_object_name(options, obj, "%s%s", name,
 427                                        entry.path);
 428                        result = options->walk(obj, OBJ_BLOB, data, options);
 429                }
 430                else {
 431                        result = error("in tree %s: entry %s has bad mode %.6o",
 432                                        describe_object(options, &tree->object), entry.path, entry.mode);
 433                }
 434                if (result < 0)
 435                        return result;
 436                if (!res)
 437                        res = result;
 438        }
 439        return res;
 440}
 441
 442static int fsck_walk_commit(struct commit *commit, void *data, struct fsck_options *options)
 443{
 444        int counter = 0, generation = 0, name_prefix_len = 0;
 445        struct commit_list *parents;
 446        int res;
 447        int result;
 448        const char *name;
 449
 450        if (parse_commit(commit))
 451                return -1;
 452
 453        name = get_object_name(options, &commit->object);
 454        if (name)
 455                put_object_name(options, &get_commit_tree(commit)->object,
 456                                "%s:", name);
 457
 458        result = options->walk((struct object *)get_commit_tree(commit),
 459                               OBJ_TREE, data, options);
 460        if (result < 0)
 461                return result;
 462        res = result;
 463
 464        parents = commit->parents;
 465        if (name && parents) {
 466                int len = strlen(name), power;
 467
 468                if (len && name[len - 1] == '^') {
 469                        generation = 1;
 470                        name_prefix_len = len - 1;
 471                }
 472                else { /* parse ~<generation> suffix */
 473                        for (generation = 0, power = 1;
 474                             len && isdigit(name[len - 1]);
 475                             power *= 10)
 476                                generation += power * (name[--len] - '0');
 477                        if (power > 1 && len && name[len - 1] == '~')
 478                                name_prefix_len = len - 1;
 479                }
 480        }
 481
 482        while (parents) {
 483                if (name) {
 484                        struct object *obj = &parents->item->object;
 485
 486                        if (++counter > 1)
 487                                put_object_name(options, obj, "%s^%d",
 488                                        name, counter);
 489                        else if (generation > 0)
 490                                put_object_name(options, obj, "%.*s~%d",
 491                                        name_prefix_len, name, generation + 1);
 492                        else
 493                                put_object_name(options, obj, "%s^", name);
 494                }
 495                result = options->walk((struct object *)parents->item, OBJ_COMMIT, data, options);
 496                if (result < 0)
 497                        return result;
 498                if (!res)
 499                        res = result;
 500                parents = parents->next;
 501        }
 502        return res;
 503}
 504
 505static int fsck_walk_tag(struct tag *tag, void *data, struct fsck_options *options)
 506{
 507        char *name = get_object_name(options, &tag->object);
 508
 509        if (parse_tag(tag))
 510                return -1;
 511        if (name)
 512                put_object_name(options, tag->tagged, "%s", name);
 513        return options->walk(tag->tagged, OBJ_ANY, data, options);
 514}
 515
 516int fsck_walk(struct object *obj, void *data, struct fsck_options *options)
 517{
 518        if (!obj)
 519                return -1;
 520
 521        if (obj->type == OBJ_NONE)
 522                parse_object(the_repository, &obj->oid);
 523
 524        switch (obj->type) {
 525        case OBJ_BLOB:
 526                return 0;
 527        case OBJ_TREE:
 528                return fsck_walk_tree((struct tree *)obj, data, options);
 529        case OBJ_COMMIT:
 530                return fsck_walk_commit((struct commit *)obj, data, options);
 531        case OBJ_TAG:
 532                return fsck_walk_tag((struct tag *)obj, data, options);
 533        default:
 534                error("Unknown object type for %s", describe_object(options, obj));
 535                return -1;
 536        }
 537}
 538
 539/*
 540 * The entries in a tree are ordered in the _path_ order,
 541 * which means that a directory entry is ordered by adding
 542 * a slash to the end of it.
 543 *
 544 * So a directory called "a" is ordered _after_ a file
 545 * called "a.c", because "a/" sorts after "a.c".
 546 */
 547#define TREE_UNORDERED (-1)
 548#define TREE_HAS_DUPS  (-2)
 549
 550static int verify_ordered(unsigned mode1, const char *name1, unsigned mode2, const char *name2)
 551{
 552        int len1 = strlen(name1);
 553        int len2 = strlen(name2);
 554        int len = len1 < len2 ? len1 : len2;
 555        unsigned char c1, c2;
 556        int cmp;
 557
 558        cmp = memcmp(name1, name2, len);
 559        if (cmp < 0)
 560                return 0;
 561        if (cmp > 0)
 562                return TREE_UNORDERED;
 563
 564        /*
 565         * Ok, the first <len> characters are the same.
 566         * Now we need to order the next one, but turn
 567         * a '\0' into a '/' for a directory entry.
 568         */
 569        c1 = name1[len];
 570        c2 = name2[len];
 571        if (!c1 && !c2)
 572                /*
 573                 * git-write-tree used to write out a nonsense tree that has
 574                 * entries with the same name, one blob and one tree.  Make
 575                 * sure we do not have duplicate entries.
 576                 */
 577                return TREE_HAS_DUPS;
 578        if (!c1 && S_ISDIR(mode1))
 579                c1 = '/';
 580        if (!c2 && S_ISDIR(mode2))
 581                c2 = '/';
 582        return c1 < c2 ? 0 : TREE_UNORDERED;
 583}
 584
 585static int fsck_tree(struct tree *item, struct fsck_options *options)
 586{
 587        int retval = 0;
 588        int has_null_sha1 = 0;
 589        int has_full_path = 0;
 590        int has_empty_name = 0;
 591        int has_dot = 0;
 592        int has_dotdot = 0;
 593        int has_dotgit = 0;
 594        int has_zero_pad = 0;
 595        int has_bad_modes = 0;
 596        int has_dup_entries = 0;
 597        int not_properly_sorted = 0;
 598        struct tree_desc desc;
 599        unsigned o_mode;
 600        const char *o_name;
 601
 602        if (init_tree_desc_gently(&desc, item->buffer, item->size)) {
 603                retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 604                return retval;
 605        }
 606
 607        o_mode = 0;
 608        o_name = NULL;
 609
 610        while (desc.size) {
 611                unsigned mode;
 612                const char *name;
 613                const struct object_id *oid;
 614
 615                oid = tree_entry_extract(&desc, &name, &mode);
 616
 617                has_null_sha1 |= is_null_oid(oid);
 618                has_full_path |= !!strchr(name, '/');
 619                has_empty_name |= !*name;
 620                has_dot |= !strcmp(name, ".");
 621                has_dotdot |= !strcmp(name, "..");
 622                has_dotgit |= is_hfs_dotgit(name) || is_ntfs_dotgit(name);
 623                has_zero_pad |= *(char *)desc.buffer == '0';
 624
 625                if (is_hfs_dotgitmodules(name) || is_ntfs_dotgitmodules(name)) {
 626                        if (!S_ISLNK(mode))
 627                                oidset_insert(&gitmodules_found, oid);
 628                        else
 629                                retval += report(options, &item->object,
 630                                                 FSCK_MSG_GITMODULES_SYMLINK,
 631                                                 ".gitmodules is a symbolic link");
 632                }
 633
 634                if (update_tree_entry_gently(&desc)) {
 635                        retval += report(options, &item->object, FSCK_MSG_BAD_TREE, "cannot be parsed as a tree");
 636                        break;
 637                }
 638
 639                switch (mode) {
 640                /*
 641                 * Standard modes..
 642                 */
 643                case S_IFREG | 0755:
 644                case S_IFREG | 0644:
 645                case S_IFLNK:
 646                case S_IFDIR:
 647                case S_IFGITLINK:
 648                        break;
 649                /*
 650                 * This is nonstandard, but we had a few of these
 651                 * early on when we honored the full set of mode
 652                 * bits..
 653                 */
 654                case S_IFREG | 0664:
 655                        if (!options->strict)
 656                                break;
 657                        /* fallthrough */
 658                default:
 659                        has_bad_modes = 1;
 660                }
 661
 662                if (o_name) {
 663                        switch (verify_ordered(o_mode, o_name, mode, name)) {
 664                        case TREE_UNORDERED:
 665                                not_properly_sorted = 1;
 666                                break;
 667                        case TREE_HAS_DUPS:
 668                                has_dup_entries = 1;
 669                                break;
 670                        default:
 671                                break;
 672                        }
 673                }
 674
 675                o_mode = mode;
 676                o_name = name;
 677        }
 678
 679        if (has_null_sha1)
 680                retval += report(options, &item->object, FSCK_MSG_NULL_SHA1, "contains entries pointing to null sha1");
 681        if (has_full_path)
 682                retval += report(options, &item->object, FSCK_MSG_FULL_PATHNAME, "contains full pathnames");
 683        if (has_empty_name)
 684                retval += report(options, &item->object, FSCK_MSG_EMPTY_NAME, "contains empty pathname");
 685        if (has_dot)
 686                retval += report(options, &item->object, FSCK_MSG_HAS_DOT, "contains '.'");
 687        if (has_dotdot)
 688                retval += report(options, &item->object, FSCK_MSG_HAS_DOTDOT, "contains '..'");
 689        if (has_dotgit)
 690                retval += report(options, &item->object, FSCK_MSG_HAS_DOTGIT, "contains '.git'");
 691        if (has_zero_pad)
 692                retval += report(options, &item->object, FSCK_MSG_ZERO_PADDED_FILEMODE, "contains zero-padded file modes");
 693        if (has_bad_modes)
 694                retval += report(options, &item->object, FSCK_MSG_BAD_FILEMODE, "contains bad file modes");
 695        if (has_dup_entries)
 696                retval += report(options, &item->object, FSCK_MSG_DUPLICATE_ENTRIES, "contains duplicate file entries");
 697        if (not_properly_sorted)
 698                retval += report(options, &item->object, FSCK_MSG_TREE_NOT_SORTED, "not properly sorted");
 699        return retval;
 700}
 701
 702static int verify_headers(const void *data, unsigned long size,
 703                          struct object *obj, struct fsck_options *options)
 704{
 705        const char *buffer = (const char *)data;
 706        unsigned long i;
 707
 708        for (i = 0; i < size; i++) {
 709                switch (buffer[i]) {
 710                case '\0':
 711                        return report(options, obj,
 712                                FSCK_MSG_NUL_IN_HEADER,
 713                                "unterminated header: NUL at offset %ld", i);
 714                case '\n':
 715                        if (i + 1 < size && buffer[i + 1] == '\n')
 716                                return 0;
 717                }
 718        }
 719
 720        /*
 721         * We did not find double-LF that separates the header
 722         * and the body.  Not having a body is not a crime but
 723         * we do want to see the terminating LF for the last header
 724         * line.
 725         */
 726        if (size && buffer[size - 1] == '\n')
 727                return 0;
 728
 729        return report(options, obj,
 730                FSCK_MSG_UNTERMINATED_HEADER, "unterminated header");
 731}
 732
 733static int fsck_ident(const char **ident, struct object *obj, struct fsck_options *options)
 734{
 735        const char *p = *ident;
 736        char *end;
 737
 738        *ident = strchrnul(*ident, '\n');
 739        if (**ident == '\n')
 740                (*ident)++;
 741
 742        if (*p == '<')
 743                return report(options, obj, FSCK_MSG_MISSING_NAME_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 744        p += strcspn(p, "<>\n");
 745        if (*p == '>')
 746                return report(options, obj, FSCK_MSG_BAD_NAME, "invalid author/committer line - bad name");
 747        if (*p != '<')
 748                return report(options, obj, FSCK_MSG_MISSING_EMAIL, "invalid author/committer line - missing email");
 749        if (p[-1] != ' ')
 750                return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_EMAIL, "invalid author/committer line - missing space before email");
 751        p++;
 752        p += strcspn(p, "<>\n");
 753        if (*p != '>')
 754                return report(options, obj, FSCK_MSG_BAD_EMAIL, "invalid author/committer line - bad email");
 755        p++;
 756        if (*p != ' ')
 757                return report(options, obj, FSCK_MSG_MISSING_SPACE_BEFORE_DATE, "invalid author/committer line - missing space before date");
 758        p++;
 759        if (*p == '0' && p[1] != ' ')
 760                return report(options, obj, FSCK_MSG_ZERO_PADDED_DATE, "invalid author/committer line - zero-padded date");
 761        if (date_overflows(parse_timestamp(p, &end, 10)))
 762                return report(options, obj, FSCK_MSG_BAD_DATE_OVERFLOW, "invalid author/committer line - date causes integer overflow");
 763        if ((end == p || *end != ' '))
 764                return report(options, obj, FSCK_MSG_BAD_DATE, "invalid author/committer line - bad date");
 765        p = end + 1;
 766        if ((*p != '+' && *p != '-') ||
 767            !isdigit(p[1]) ||
 768            !isdigit(p[2]) ||
 769            !isdigit(p[3]) ||
 770            !isdigit(p[4]) ||
 771            (p[5] != '\n'))
 772                return report(options, obj, FSCK_MSG_BAD_TIMEZONE, "invalid author/committer line - bad time zone");
 773        p += 6;
 774        return 0;
 775}
 776
 777static int fsck_commit_buffer(struct commit *commit, const char *buffer,
 778        unsigned long size, struct fsck_options *options)
 779{
 780        struct object_id tree_oid, oid;
 781        struct commit_graft *graft;
 782        unsigned parent_count, parent_line_count = 0, author_count;
 783        int err;
 784        const char *buffer_begin = buffer;
 785        const char *p;
 786
 787        if (verify_headers(buffer, size, &commit->object, options))
 788                return -1;
 789
 790        if (!skip_prefix(buffer, "tree ", &buffer))
 791                return report(options, &commit->object, FSCK_MSG_MISSING_TREE, "invalid format - expected 'tree' line");
 792        if (parse_oid_hex(buffer, &tree_oid, &p) || *p != '\n') {
 793                err = report(options, &commit->object, FSCK_MSG_BAD_TREE_SHA1, "invalid 'tree' line format - bad sha1");
 794                if (err)
 795                        return err;
 796        }
 797        buffer = p + 1;
 798        while (skip_prefix(buffer, "parent ", &buffer)) {
 799                if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
 800                        err = report(options, &commit->object, FSCK_MSG_BAD_PARENT_SHA1, "invalid 'parent' line format - bad sha1");
 801                        if (err)
 802                                return err;
 803                }
 804                buffer = p + 1;
 805                parent_line_count++;
 806        }
 807        graft = lookup_commit_graft(the_repository, &commit->object.oid);
 808        parent_count = commit_list_count(commit->parents);
 809        if (graft) {
 810                if (graft->nr_parent == -1 && !parent_count)
 811                        ; /* shallow commit */
 812                else if (graft->nr_parent != parent_count) {
 813                        err = report(options, &commit->object, FSCK_MSG_MISSING_GRAFT, "graft objects missing");
 814                        if (err)
 815                                return err;
 816                }
 817        } else {
 818                if (parent_count != parent_line_count) {
 819                        err = report(options, &commit->object, FSCK_MSG_MISSING_PARENT, "parent objects missing");
 820                        if (err)
 821                                return err;
 822                }
 823        }
 824        author_count = 0;
 825        while (skip_prefix(buffer, "author ", &buffer)) {
 826                author_count++;
 827                err = fsck_ident(&buffer, &commit->object, options);
 828                if (err)
 829                        return err;
 830        }
 831        if (author_count < 1)
 832                err = report(options, &commit->object, FSCK_MSG_MISSING_AUTHOR, "invalid format - expected 'author' line");
 833        else if (author_count > 1)
 834                err = report(options, &commit->object, FSCK_MSG_MULTIPLE_AUTHORS, "invalid format - multiple 'author' lines");
 835        if (err)
 836                return err;
 837        if (!skip_prefix(buffer, "committer ", &buffer))
 838                return report(options, &commit->object, FSCK_MSG_MISSING_COMMITTER, "invalid format - expected 'committer' line");
 839        err = fsck_ident(&buffer, &commit->object, options);
 840        if (err)
 841                return err;
 842        if (!get_commit_tree(commit)) {
 843                err = report(options, &commit->object, FSCK_MSG_BAD_TREE, "could not load commit's tree %s", oid_to_hex(&tree_oid));
 844                if (err)
 845                        return err;
 846        }
 847        if (memchr(buffer_begin, '\0', size)) {
 848                err = report(options, &commit->object, FSCK_MSG_NUL_IN_COMMIT,
 849                             "NUL byte in the commit object body");
 850                if (err)
 851                        return err;
 852        }
 853        return 0;
 854}
 855
 856static int fsck_commit(struct commit *commit, const char *data,
 857        unsigned long size, struct fsck_options *options)
 858{
 859        const char *buffer = data ?  data : get_commit_buffer(commit, &size);
 860        int ret = fsck_commit_buffer(commit, buffer, size, options);
 861        if (!data)
 862                unuse_commit_buffer(commit, buffer);
 863        return ret;
 864}
 865
 866static int fsck_tag_buffer(struct tag *tag, const char *data,
 867        unsigned long size, struct fsck_options *options)
 868{
 869        struct object_id oid;
 870        int ret = 0;
 871        const char *buffer;
 872        char *to_free = NULL, *eol;
 873        struct strbuf sb = STRBUF_INIT;
 874        const char *p;
 875
 876        if (data)
 877                buffer = data;
 878        else {
 879                enum object_type type;
 880
 881                buffer = to_free =
 882                        read_object_file(&tag->object.oid, &type, &size);
 883                if (!buffer)
 884                        return report(options, &tag->object,
 885                                FSCK_MSG_MISSING_TAG_OBJECT,
 886                                "cannot read tag object");
 887
 888                if (type != OBJ_TAG) {
 889                        ret = report(options, &tag->object,
 890                                FSCK_MSG_TAG_OBJECT_NOT_TAG,
 891                                "expected tag got %s",
 892                            type_name(type));
 893                        goto done;
 894                }
 895        }
 896
 897        ret = verify_headers(buffer, size, &tag->object, options);
 898        if (ret)
 899                goto done;
 900
 901        if (!skip_prefix(buffer, "object ", &buffer)) {
 902                ret = report(options, &tag->object, FSCK_MSG_MISSING_OBJECT, "invalid format - expected 'object' line");
 903                goto done;
 904        }
 905        if (parse_oid_hex(buffer, &oid, &p) || *p != '\n') {
 906                ret = report(options, &tag->object, FSCK_MSG_BAD_OBJECT_SHA1, "invalid 'object' line format - bad sha1");
 907                if (ret)
 908                        goto done;
 909        }
 910        buffer = p + 1;
 911
 912        if (!skip_prefix(buffer, "type ", &buffer)) {
 913                ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE_ENTRY, "invalid format - expected 'type' line");
 914                goto done;
 915        }
 916        eol = strchr(buffer, '\n');
 917        if (!eol) {
 918                ret = report(options, &tag->object, FSCK_MSG_MISSING_TYPE, "invalid format - unexpected end after 'type' line");
 919                goto done;
 920        }
 921        if (type_from_string_gently(buffer, eol - buffer, 1) < 0)
 922                ret = report(options, &tag->object, FSCK_MSG_BAD_TYPE, "invalid 'type' value");
 923        if (ret)
 924                goto done;
 925        buffer = eol + 1;
 926
 927        if (!skip_prefix(buffer, "tag ", &buffer)) {
 928                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG_ENTRY, "invalid format - expected 'tag' line");
 929                goto done;
 930        }
 931        eol = strchr(buffer, '\n');
 932        if (!eol) {
 933                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAG, "invalid format - unexpected end after 'type' line");
 934                goto done;
 935        }
 936        strbuf_addf(&sb, "refs/tags/%.*s", (int)(eol - buffer), buffer);
 937        if (check_refname_format(sb.buf, 0)) {
 938                ret = report(options, &tag->object, FSCK_MSG_BAD_TAG_NAME,
 939                           "invalid 'tag' name: %.*s",
 940                           (int)(eol - buffer), buffer);
 941                if (ret)
 942                        goto done;
 943        }
 944        buffer = eol + 1;
 945
 946        if (!skip_prefix(buffer, "tagger ", &buffer)) {
 947                /* early tags do not contain 'tagger' lines; warn only */
 948                ret = report(options, &tag->object, FSCK_MSG_MISSING_TAGGER_ENTRY, "invalid format - expected 'tagger' line");
 949                if (ret)
 950                        goto done;
 951        }
 952        else
 953                ret = fsck_ident(&buffer, &tag->object, options);
 954
 955done:
 956        strbuf_release(&sb);
 957        free(to_free);
 958        return ret;
 959}
 960
 961static int fsck_tag(struct tag *tag, const char *data,
 962        unsigned long size, struct fsck_options *options)
 963{
 964        struct object *tagged = tag->tagged;
 965
 966        if (!tagged)
 967                return report(options, &tag->object, FSCK_MSG_BAD_TAG_OBJECT, "could not load tagged object");
 968
 969        return fsck_tag_buffer(tag, data, size, options);
 970}
 971
 972struct fsck_gitmodules_data {
 973        struct object *obj;
 974        struct fsck_options *options;
 975        int ret;
 976};
 977
 978static int fsck_gitmodules_fn(const char *var, const char *value, void *vdata)
 979{
 980        struct fsck_gitmodules_data *data = vdata;
 981        const char *subsection, *key;
 982        int subsection_len;
 983        char *name;
 984
 985        if (parse_config_key(var, "submodule", &subsection, &subsection_len, &key) < 0 ||
 986            !subsection)
 987                return 0;
 988
 989        name = xmemdupz(subsection, subsection_len);
 990        if (check_submodule_name(name) < 0)
 991                data->ret |= report(data->options, data->obj,
 992                                    FSCK_MSG_GITMODULES_NAME,
 993                                    "disallowed submodule name: %s",
 994                                    name);
 995        free(name);
 996
 997        return 0;
 998}
 999
1000static int fsck_blob(struct blob *blob, const char *buf,
1001                     unsigned long size, struct fsck_options *options)
1002{
1003        struct fsck_gitmodules_data data;
1004        struct config_options config_opts = { 0 };
1005
1006        if (!oidset_contains(&gitmodules_found, &blob->object.oid))
1007                return 0;
1008        oidset_insert(&gitmodules_done, &blob->object.oid);
1009
1010        if (object_on_skiplist(options, &blob->object))
1011                return 0;
1012
1013        if (!buf) {
1014                /*
1015                 * A missing buffer here is a sign that the caller found the
1016                 * blob too gigantic to load into memory. Let's just consider
1017                 * that an error.
1018                 */
1019                return report(options, &blob->object,
1020                              FSCK_MSG_GITMODULES_LARGE,
1021                              ".gitmodules too large to parse");
1022        }
1023
1024        data.obj = &blob->object;
1025        data.options = options;
1026        data.ret = 0;
1027        config_opts.error_action = CONFIG_ERROR_SILENT;
1028        if (git_config_from_mem(fsck_gitmodules_fn, CONFIG_ORIGIN_BLOB,
1029                                ".gitmodules", buf, size, &data, &config_opts))
1030                data.ret |= report(options, &blob->object,
1031                                   FSCK_MSG_GITMODULES_PARSE,
1032                                   "could not parse gitmodules blob");
1033
1034        return data.ret;
1035}
1036
1037int fsck_object(struct object *obj, void *data, unsigned long size,
1038        struct fsck_options *options)
1039{
1040        if (!obj)
1041                return report(options, obj, FSCK_MSG_BAD_OBJECT_SHA1, "no valid object to fsck");
1042
1043        if (obj->type == OBJ_BLOB)
1044                return fsck_blob((struct blob *)obj, data, size, options);
1045        if (obj->type == OBJ_TREE)
1046                return fsck_tree((struct tree *) obj, options);
1047        if (obj->type == OBJ_COMMIT)
1048                return fsck_commit((struct commit *) obj, (const char *) data,
1049                        size, options);
1050        if (obj->type == OBJ_TAG)
1051                return fsck_tag((struct tag *) obj, (const char *) data,
1052                        size, options);
1053
1054        return report(options, obj, FSCK_MSG_UNKNOWN_TYPE, "unknown type '%d' (internal fsck error)",
1055                          obj->type);
1056}
1057
1058int fsck_error_function(struct fsck_options *o,
1059        struct object *obj, int msg_type, const char *message)
1060{
1061        if (msg_type == FSCK_WARN) {
1062                warning("object %s: %s", describe_object(o, obj), message);
1063                return 0;
1064        }
1065        error("object %s: %s", describe_object(o, obj), message);
1066        return 1;
1067}
1068
1069int fsck_finish(struct fsck_options *options)
1070{
1071        int ret = 0;
1072        struct oidset_iter iter;
1073        const struct object_id *oid;
1074
1075        oidset_iter_init(&gitmodules_found, &iter);
1076        while ((oid = oidset_iter_next(&iter))) {
1077                struct blob *blob;
1078                enum object_type type;
1079                unsigned long size;
1080                char *buf;
1081
1082                if (oidset_contains(&gitmodules_done, oid))
1083                        continue;
1084
1085                blob = lookup_blob(the_repository, oid);
1086                if (!blob) {
1087                        struct object *obj = lookup_unknown_object(oid->hash);
1088                        ret |= report(options, obj,
1089                                      FSCK_MSG_GITMODULES_BLOB,
1090                                      "non-blob found at .gitmodules");
1091                        continue;
1092                }
1093
1094                buf = read_object_file(oid, &type, &size);
1095                if (!buf) {
1096                        if (is_promisor_object(&blob->object.oid))
1097                                continue;
1098                        ret |= report(options, &blob->object,
1099                                      FSCK_MSG_GITMODULES_MISSING,
1100                                      "unable to read .gitmodules blob");
1101                        continue;
1102                }
1103
1104                if (type == OBJ_BLOB)
1105                        ret |= fsck_blob(blob, buf, size, options);
1106                else
1107                        ret |= report(options, &blob->object,
1108                                      FSCK_MSG_GITMODULES_BLOB,
1109                                      "non-blob found at .gitmodules");
1110                free(buf);
1111        }
1112
1113
1114        oidset_clear(&gitmodules_found);
1115        oidset_clear(&gitmodules_done);
1116        return ret;
1117}