Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "pack.h"
   3
   4static 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;
  14
  15        hdr = p->pack_base;
  16        if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
  17                return error("Packfile signature mismatch", p->pack_name);
  18        if (hdr->hdr_version != htonl(PACK_VERSION))
  19                return error("Packfile version %d different from ours %d",
  20                             ntohl(hdr->hdr_version), PACK_VERSION);
  21        nr_objects = ntohl(hdr->hdr_entries);
  22        if (num_packed_objects(p) != nr_objects)
  23                return error("Packfile claims to have %d objects, "
  24                             "while idx size expects %d", nr_objects,
  25                             num_packed_objects(p));
  26
  27        SHA1_Init(&ctx);
  28        pack_base = p->pack_base;
  29        SHA1_Update(&ctx, pack_base, pack_size - 20);
  30        SHA1_Final(sha1, &ctx);
  31        if (memcmp(sha1, index_base + index_size - 40, 20))
  32                return error("Packfile %s SHA1 mismatch with idx",
  33                             p->pack_name);
  34        if (memcmp(sha1, pack_base + pack_size - 20, 20))
  35                return error("Packfile %s SHA1 mismatch with itself",
  36                             p->pack_name);
  37        return 0;
  38}
  39
  40
  41int verify_pack(struct packed_git *p)
  42{
  43        unsigned long index_size = p->index_size;
  44        void *index_base = p->index_base;
  45        SHA_CTX ctx;
  46        unsigned char sha1[20];
  47        int ret;
  48
  49        /* Verify SHA1 sum of the index file */
  50        SHA1_Init(&ctx);
  51        SHA1_Update(&ctx, index_base, index_size - 20);
  52        SHA1_Final(sha1, &ctx);
  53        if (memcmp(sha1, index_base + index_size - 20, 20))
  54                return error("Packfile index for %s SHA1 mismatch",
  55                             p->pack_name);
  56
  57        /* Verify pack file */
  58        use_packed_git(p);
  59        ret = verify_packfile(p);
  60        unuse_packed_git(p);
  61        return ret;
  62}