1 #include "cache.h" 2 #include "repository.h" 3 #include "pack.h" 4 #include "pack-revindex.h" 5 #include "progress.h" 6 #include "packfile.h" 7 #include "object-store.h" 8 9 struct idx_entry { 10 off_t offset; 11 unsigned int nr; 12 }; 13 14 static int compare_entries(const void *e1, const void *e2) 15 { 16 const struct idx_entry *entry1 = e1; 17 const struct idx_entry *entry2 = e2; 18 if (entry1->offset < entry2->offset) 19 return -1; 20 if (entry1->offset > entry2->offset) 21 return 1; 22 return 0; 23 } 24 25 int check_pack_crc(struct packed_git *p, struct pack_window **w_curs, 26 off_t offset, off_t len, unsigned int nr) 27 { 28 const uint32_t *index_crc; 29 uint32_t data_crc = crc32(0, NULL, 0); 30 31 do { 32 unsigned long avail; 33 void *data = use_pack(p, w_curs, offset, &avail); 34 if (avail > len) 35 avail = len; 36 data_crc = crc32(data_crc, data, avail); 37 offset += avail; 38 len -= avail; 39 } while (len); 40 41 index_crc = p->index_data; 42 index_crc += 2 + 256 + (size_t)p->num_objects * (the_hash_algo->rawsz/4) + nr; 43 44 return data_crc != ntohl(*index_crc); 45 } 46 47 static int verify_packfile(struct repository *r, 48 struct packed_git *p, 49 struct pack_window **w_curs, 50 verify_fn fn, 51 struct progress *progress, uint32_t base_count) 52 53 { 54 off_t index_size = p->index_size; 55 const unsigned char *index_base = p->index_data; 56 git_hash_ctx ctx; 57 unsigned char hash[GIT_MAX_RAWSZ], *pack_sig; 58 off_t offset = 0, pack_sig_ofs = 0; 59 uint32_t nr_objects, i; 60 int err = 0; 61 struct idx_entry *entries; 62 63 if (!is_pack_valid(p)) 64 return error("packfile %s cannot be accessed", p->pack_name); 65 66 r->hash_algo->init_fn(&ctx); 67 do { 68 unsigned long remaining; 69 unsigned char *in = use_pack(p, w_curs, offset, &remaining); 70 offset += remaining; 71 if (!pack_sig_ofs) 72 pack_sig_ofs = p->pack_size - r->hash_algo->rawsz; 73 if (offset > pack_sig_ofs) 74 remaining -= (unsigned int)(offset - pack_sig_ofs); 75 r->hash_algo->update_fn(&ctx, in, remaining); 76 } while (offset < pack_sig_ofs); 77 r->hash_algo->final_fn(hash, &ctx); 78 pack_sig = use_pack(p, w_curs, pack_sig_ofs, NULL); 79 if (!hasheq(hash, pack_sig)) 80 err = error("%s pack checksum mismatch", 81 p->pack_name); 82 if (!hasheq(index_base + index_size - r->hash_algo->hexsz, pack_sig)) 83 err = error("%s pack checksum does not match its index", 84 p->pack_name); 85 unuse_pack(w_curs); 86 87 /* Make sure everything reachable from idx is valid. Since we 88 * have verified that nr_objects matches between idx and pack, 89 * we do not do scan-streaming check on the pack file. 90 */ 91 nr_objects = p->num_objects; 92 ALLOC_ARRAY(entries, nr_objects + 1); 93 entries[nr_objects].offset = pack_sig_ofs; 94 /* first sort entries by pack offset, since unpacking them is more efficient that way */ 95 for (i = 0; i < nr_objects; i++) { 96 entries[i].offset = nth_packed_object_offset(p, i); 97 entries[i].nr = i; 98 } 99 QSORT(entries, nr_objects, compare_entries); 100 101 for (i = 0; i < nr_objects; i++) { 102 void *data; 103 struct object_id oid; 104 enum object_type type; 105 unsigned long size; 106 off_t curpos; 107 int data_valid; 108 109 if (nth_packed_object_id(&oid, p, entries[i].nr) < 0) 110 BUG("unable to get oid of object %lu from %s", 111 (unsigned long)entries[i].nr, p->pack_name); 112 113 if (p->index_version > 1) { 114 off_t offset = entries[i].offset; 115 off_t len = entries[i+1].offset - offset; 116 unsigned int nr = entries[i].nr; 117 if (check_pack_crc(p, w_curs, offset, len, nr)) 118 err = error("index CRC mismatch for object %s " 119 "from %s at offset %"PRIuMAX"", 120 oid_to_hex(&oid), 121 p->pack_name, (uintmax_t)offset); 122 } 123 124 curpos = entries[i].offset; 125 type = unpack_object_header(p, w_curs, &curpos, &size); 126 unuse_pack(w_curs); 127 128 if (type == OBJ_BLOB && big_file_threshold <= size) { 129 /* 130 * Let check_object_signature() check it with 131 * the streaming interface; no point slurping 132 * the data in-core only to discard. 133 */ 134 data = NULL; 135 data_valid = 0; 136 } else { 137 data = unpack_entry(r, p, entries[i].offset, &type, &size); 138 data_valid = 1; 139 } 140 141 if (data_valid && !data) 142 err = error("cannot unpack %s from %s at offset %"PRIuMAX"", 143 oid_to_hex(&oid), p->pack_name, 144 (uintmax_t)entries[i].offset); 145 else if (check_object_signature(r, &oid, data, size, 146 type_name(type), NULL)) 147 err = error("packed %s from %s is corrupt", 148 oid_to_hex(&oid), p->pack_name); 149 else if (fn) { 150 int eaten = 0; 151 err |= fn(&oid, type, size, data, &eaten); 152 if (eaten) 153 data = NULL; 154 } 155 if (((base_count + i) & 1023) == 0) 156 display_progress(progress, base_count + i); 157 free(data); 158 159 } 160 display_progress(progress, base_count + i); 161 free(entries); 162 163 return err; 164 } 165 166 int verify_pack_index(struct packed_git *p) 167 { 168 int err = 0; 169 170 if (open_pack_index(p)) 171 return error("packfile %s index not opened", p->pack_name); 172 173 /* Verify SHA1 sum of the index file */ 174 if (!hashfile_checksum_valid(p->index_data, p->index_size)) 175 err = error("Packfile index for %s hash mismatch", 176 p->pack_name); 177 return err; 178 } 179 180 int verify_pack(struct repository *r, struct packed_git *p, verify_fn fn, 181 struct progress *progress, uint32_t base_count) 182 { 183 int err = 0; 184 struct pack_window *w_curs = NULL; 185 186 err |= verify_pack_index(p); 187 if (!p->index_data) 188 return -1; 189 190 err |= verify_packfile(r, p, &w_curs, fn, progress, base_count); 191 unuse_pack(&w_curs); 192 193 return err; 194 } 195