pack-check.c

   1 #include "cache.h"
   2 #include "pack.h"
   3
   4 static int verify_packfile(struct packed_git *p)
   5 {
   6         unsigned long index_size = p->index_size;
   7         void *index_base = p->index_base;
   8         SHA_CTX ctx;
   9         unsigned char sha1[20];
  10         unsigned long pack_size = p->pack_size;
  11         void *pack_base;
  12         struct pack_header *hdr;
  13         int nr_objects, err, i;
  14
  15         /* Header consistency check */
  16         hdr = p->pack_base;
  17         if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
  18                 return error("Packfile %s signature mismatch", p->pack_name);
  19         if (!pack_version_ok(hdr->hdr_version))
  20                 return error("Packfile version %d unsupported",
  21                              ntohl(hdr->hdr_version));
  22         nr_objects = ntohl(hdr->hdr_entries);
  23         if (num_packed_objects(p) != nr_objects)
  24                 return error("Packfile claims to have %d objects, "
  25                              "while idx size expects %d", nr_objects,
  26                              num_packed_objects(p));
  27
  28         SHA1_Init(&ctx);
  29         pack_base = p->pack_base;
  30         SHA1_Update(&ctx, pack_base, pack_size - 20);
  31         SHA1_Final(sha1, &ctx);
  32         if (memcmp(sha1, index_base + index_size - 40, 20))
  33                 return error("Packfile %s SHA1 mismatch with idx",
  34                              p->pack_name);
  35         if (memcmp(sha1, pack_base + pack_size - 20, 20))
  36                 return error("Packfile %s SHA1 mismatch with itself",
  37                              p->pack_name);
  38
  39         /* Make sure everything reachable from idx is valid.  Since we
  40          * have verified that nr_objects matches between idx and pack,
  41          * we do not do scan-streaming check on the pack file.
  42          */
  43         for (i = err = 0; i < nr_objects; i++) {
  44                 unsigned char sha1[20];
  45                 struct pack_entry e;
  46                 void *data;
  47                 char type[20];
  48                 unsigned long size;
  49
  50                 if (nth_packed_object_sha1(p, i, sha1))
  51                         die("internal error pack-check nth-packed-object");
  52                 if (!find_pack_entry_one(sha1, &e, p))
  53                         die("internal error pack-check find-pack-entry-one");
  54                 data = unpack_entry_gently(&e, type, &size);
  55                 if (!data) {
  56                         err = error("cannot unpack %s from %s",
  57                                     sha1_to_hex(sha1), p->pack_name);
  58                         continue;
  59                 }
  60                 if (check_sha1_signature(sha1, data, size, type)) {
  61                         err = error("packed %s from %s is corrupt",
  62                                     sha1_to_hex(sha1), p->pack_name);
  63                         free(data);
  64                         continue;
  65                 }
  66                 free(data);
  67         }
  68
  69         return err;
  70 }
  71
  72
  73 static void show_pack_info(struct packed_git *p)
  74 {
  75         struct pack_header *hdr;
  76         int nr_objects, i;
  77
  78         hdr = p->pack_base;
  79         nr_objects = ntohl(hdr->hdr_entries);
  80
  81         for (i = 0; i < nr_objects; i++) {
  82                 unsigned char sha1[20], base_sha1[20];
  83                 struct pack_entry e;
  84                 char type[20];
  85                 unsigned long size;
  86                 unsigned long store_size;
  87                 int delta_chain_length;
  88
  89                 if (nth_packed_object_sha1(p, i, sha1))
  90                         die("internal error pack-check nth-packed-object");
  91                 if (!find_pack_entry_one(sha1, &e, p))
  92                         die("internal error pack-check find-pack-entry-one");
  93
  94                 packed_object_info_detail(&e, type, &size, &store_size,
  95                                           &delta_chain_length,
  96                                           base_sha1);
  97                 printf("%s ", sha1_to_hex(sha1));
  98                 if (!delta_chain_length)
  99                         printf("%-6s %lu %u\n", type, size, e.offset);
 100                 else
 101                         printf("%-6s %lu %u %d %s\n", type, size, e.offset,
 102                                delta_chain_length, sha1_to_hex(base_sha1));
 103         }
 104
 105 }
 106
 107 int verify_pack(struct packed_git *p, int verbose)
 108 {
 109         unsigned long index_size = p->index_size;
 110         void *index_base = p->index_base;
 111         SHA_CTX ctx;
 112         unsigned char sha1[20];
 113         int ret;
 114
 115         ret = 0;
 116         /* Verify SHA1 sum of the index file */
 117         SHA1_Init(&ctx);
 118         SHA1_Update(&ctx, index_base, index_size - 20);
 119         SHA1_Final(sha1, &ctx);
 120         if (memcmp(sha1, index_base + index_size - 20, 20))
 121                 ret = error("Packfile index for %s SHA1 mismatch",
 122                             p->pack_name);
 123
 124         if (!ret) {
 125                 /* Verify pack file */
 126                 use_packed_git(p);
 127                 ret = verify_packfile(p);
 128                 unuse_packed_git(p);
 129         }
 130
 131         if (verbose) {
 132                 if (ret)
 133                         printf("%s: bad\n", p->pack_name);
 134                 else {
 135                         use_packed_git(p);
 136                         show_pack_info(p);
 137                         unuse_packed_git(p);
 138                         printf("%s: ok\n", p->pack_name);
 139                 }
 140         }
 141
 142         return ret;
 143 }