Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "pack.h"
   3
   4#define BATCH (1u<<20)
   5
   6static int verify_packfile(struct packed_git *p)
   7{
   8        unsigned long index_size = p->index_size;
   9        void *index_base = p->index_base;
  10        SHA_CTX ctx;
  11        unsigned char sha1[20];
  12        struct pack_header *hdr;
  13        int nr_objects, err, i;
  14        unsigned char *packdata;
  15        unsigned long datasize;
  16
  17        /* Header consistency check */
  18        hdr = p->pack_base;
  19        if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
  20                return error("Packfile %s signature mismatch", p->pack_name);
  21        if (!pack_version_ok(hdr->hdr_version))
  22                return error("Packfile version %d unsupported",
  23                             ntohl(hdr->hdr_version));
  24        nr_objects = ntohl(hdr->hdr_entries);
  25        if (num_packed_objects(p) != nr_objects)
  26                return error("Packfile claims to have %d objects, "
  27                             "while idx size expects %d", nr_objects,
  28                             num_packed_objects(p));
  29
  30        /* Check integrity of pack data with its SHA-1 checksum */
  31        SHA1_Init(&ctx);
  32        packdata = p->pack_base;
  33        datasize = p->pack_size - 20;
  34        while (datasize) {
  35                unsigned long batch = (datasize < BATCH) ? datasize : BATCH;
  36                SHA1_Update(&ctx, packdata, batch);
  37                datasize -= batch;
  38                packdata += batch;
  39        }
  40        SHA1_Final(sha1, &ctx);
  41
  42        if (hashcmp(sha1, (unsigned char *)(p->pack_base) + p->pack_size - 20))
  43                return error("Packfile %s SHA1 mismatch with itself",
  44                             p->pack_name);
  45        if (hashcmp(sha1, (unsigned char *)index_base + index_size - 40))
  46                return error("Packfile %s SHA1 mismatch with idx",
  47                             p->pack_name);
  48
  49        /* Make sure everything reachable from idx is valid.  Since we
  50         * have verified that nr_objects matches between idx and pack,
  51         * we do not do scan-streaming check on the pack file.
  52         */
  53        for (i = err = 0; i < nr_objects; i++) {
  54                unsigned char sha1[20];
  55                void *data;
  56                char type[20];
  57                unsigned long size, offset;
  58
  59                if (nth_packed_object_sha1(p, i, sha1))
  60                        die("internal error pack-check nth-packed-object");
  61                offset = find_pack_entry_one(sha1, p);
  62                if (!offset)
  63                        die("internal error pack-check find-pack-entry-one");
  64                data = unpack_entry_gently(p, offset, type, &size);
  65                if (!data) {
  66                        err = error("cannot unpack %s from %s",
  67                                    sha1_to_hex(sha1), p->pack_name);
  68                        continue;
  69                }
  70                if (check_sha1_signature(sha1, data, size, type)) {
  71                        err = error("packed %s from %s is corrupt",
  72                                    sha1_to_hex(sha1), p->pack_name);
  73                        free(data);
  74                        continue;
  75                }
  76                free(data);
  77        }
  78
  79        return err;
  80}
  81
  82
  83#define MAX_CHAIN 40
  84
  85static void show_pack_info(struct packed_git *p)
  86{
  87        struct pack_header *hdr;
  88        int nr_objects, i;
  89        unsigned int chain_histogram[MAX_CHAIN];
  90
  91        hdr = p->pack_base;
  92        nr_objects = ntohl(hdr->hdr_entries);
  93        memset(chain_histogram, 0, sizeof(chain_histogram));
  94
  95        for (i = 0; i < nr_objects; i++) {
  96                unsigned char sha1[20], base_sha1[20];
  97                char type[20];
  98                unsigned long size;
  99                unsigned long store_size;
 100                unsigned long offset;
 101                unsigned int delta_chain_length;
 102
 103                if (nth_packed_object_sha1(p, i, sha1))
 104                        die("internal error pack-check nth-packed-object");
 105                offset = find_pack_entry_one(sha1, p);
 106                if (!offset)
 107                        die("internal error pack-check find-pack-entry-one");
 108
 109                packed_object_info_detail(p, offset, type, &size, &store_size,
 110                                          &delta_chain_length,
 111                                          base_sha1);
 112                printf("%s ", sha1_to_hex(sha1));
 113                if (!delta_chain_length)
 114                        printf("%-6s %lu %lu\n", type, size, offset);
 115                else {
 116                        printf("%-6s %lu %lu %u %s\n", type, size, offset,
 117                               delta_chain_length, sha1_to_hex(base_sha1));
 118                        if (delta_chain_length < MAX_CHAIN)
 119                                chain_histogram[delta_chain_length]++;
 120                        else
 121                                chain_histogram[0]++;
 122                }
 123        }
 124
 125        for (i = 0; i < MAX_CHAIN; i++) {
 126                if (!chain_histogram[i])
 127                        continue;
 128                printf("chain length %s %d: %d object%s\n",
 129                       i ? "=" : ">=",
 130                       i ? i : MAX_CHAIN,
 131                       chain_histogram[i],
 132                       1 < chain_histogram[i] ? "s" : "");
 133        }
 134}
 135
 136int verify_pack(struct packed_git *p, int verbose)
 137{
 138        unsigned long index_size = p->index_size;
 139        void *index_base = p->index_base;
 140        SHA_CTX ctx;
 141        unsigned char sha1[20];
 142        int ret;
 143
 144        ret = 0;
 145        /* Verify SHA1 sum of the index file */
 146        SHA1_Init(&ctx);
 147        SHA1_Update(&ctx, index_base, index_size - 20);
 148        SHA1_Final(sha1, &ctx);
 149        if (hashcmp(sha1, (unsigned char *)index_base + index_size - 20))
 150                ret = error("Packfile index for %s SHA1 mismatch",
 151                            p->pack_name);
 152
 153        if (!ret) {
 154                /* Verify pack file */
 155                use_packed_git(p);
 156                ret = verify_packfile(p);
 157                unuse_packed_git(p);
 158        }
 159
 160        if (verbose) {
 161                if (ret)
 162                        printf("%s: bad\n", p->pack_name);
 163                else {
 164                        use_packed_git(p);
 165                        show_pack_info(p);
 166                        unuse_packed_git(p);
 167                        printf("%s: ok\n", p->pack_name);
 168                }
 169        }
 170
 171        return ret;
 172}