sha1_file: convert check_sha1_signature to struct object_id
[git] / pack-check.c
1 #include "cache.h"
2 #include "pack.h"
3 #include "pack-revindex.h"
4 #include "progress.h"
5 #include "packfile.h"
6
7 struct idx_entry {
8         off_t                offset;
9         union idx_entry_object {
10                 const unsigned char *hash;
11                 struct object_id *oid;
12         } oid;
13         unsigned int nr;
14 };
15
16 static int compare_entries(const void *e1, const void *e2)
17 {
18         const struct idx_entry *entry1 = e1;
19         const struct idx_entry *entry2 = e2;
20         if (entry1->offset < entry2->offset)
21                 return -1;
22         if (entry1->offset > entry2->offset)
23                 return 1;
24         return 0;
25 }
26
27 int check_pack_crc(struct packed_git *p, struct pack_window **w_curs,
28                    off_t offset, off_t len, unsigned int nr)
29 {
30         const uint32_t *index_crc;
31         uint32_t data_crc = crc32(0, NULL, 0);
32
33         do {
34                 unsigned long avail;
35                 void *data = use_pack(p, w_curs, offset, &avail);
36                 if (avail > len)
37                         avail = len;
38                 data_crc = crc32(data_crc, data, avail);
39                 offset += avail;
40                 len -= avail;
41         } while (len);
42
43         index_crc = p->index_data;
44         index_crc += 2 + 256 + p->num_objects * (the_hash_algo->rawsz/4) + nr;
45
46         return data_crc != ntohl(*index_crc);
47 }
48
49 static int verify_packfile(struct packed_git *p,
50                            struct pack_window **w_curs,
51                            verify_fn fn,
52                            struct progress *progress, uint32_t base_count)
53
54 {
55         off_t index_size = p->index_size;
56         const unsigned char *index_base = p->index_data;
57         git_hash_ctx ctx;
58         unsigned char hash[GIT_MAX_RAWSZ], *pack_sig;
59         off_t offset = 0, pack_sig_ofs = 0;
60         uint32_t nr_objects, i;
61         int err = 0;
62         struct idx_entry *entries;
63
64         if (!is_pack_valid(p))
65                 return error("packfile %s cannot be accessed", p->pack_name);
66
67         the_hash_algo->init_fn(&ctx);
68         do {
69                 unsigned long remaining;
70                 unsigned char *in = use_pack(p, w_curs, offset, &remaining);
71                 offset += remaining;
72                 if (!pack_sig_ofs)
73                         pack_sig_ofs = p->pack_size - the_hash_algo->rawsz;
74                 if (offset > pack_sig_ofs)
75                         remaining -= (unsigned int)(offset - pack_sig_ofs);
76                 the_hash_algo->update_fn(&ctx, in, remaining);
77         } while (offset < pack_sig_ofs);
78         the_hash_algo->final_fn(hash, &ctx);
79         pack_sig = use_pack(p, w_curs, pack_sig_ofs, NULL);
80         if (hashcmp(hash, pack_sig))
81                 err = error("%s pack checksum mismatch",
82                             p->pack_name);
83         if (hashcmp(index_base + index_size - the_hash_algo->hexsz, pack_sig))
84                 err = error("%s pack checksum does not match its index",
85                             p->pack_name);
86         unuse_pack(w_curs);
87
88         /* Make sure everything reachable from idx is valid.  Since we
89          * have verified that nr_objects matches between idx and pack,
90          * we do not do scan-streaming check on the pack file.
91          */
92         nr_objects = p->num_objects;
93         ALLOC_ARRAY(entries, nr_objects + 1);
94         entries[nr_objects].offset = pack_sig_ofs;
95         /* first sort entries by pack offset, since unpacking them is more efficient that way */
96         for (i = 0; i < nr_objects; i++) {
97                 entries[i].oid.hash = nth_packed_object_sha1(p, i);
98                 if (!entries[i].oid.hash)
99                         die("internal error pack-check nth-packed-object");
100                 entries[i].offset = nth_packed_object_offset(p, i);
101                 entries[i].nr = i;
102         }
103         QSORT(entries, nr_objects, compare_entries);
104
105         for (i = 0; i < nr_objects; i++) {
106                 void *data;
107                 enum object_type type;
108                 unsigned long size;
109                 off_t curpos;
110                 int data_valid;
111
112                 if (p->index_version > 1) {
113                         off_t offset = entries[i].offset;
114                         off_t len = entries[i+1].offset - offset;
115                         unsigned int nr = entries[i].nr;
116                         if (check_pack_crc(p, w_curs, offset, len, nr))
117                                 err = error("index CRC mismatch for object %s "
118                                             "from %s at offset %"PRIuMAX"",
119                                             oid_to_hex(entries[i].oid.oid),
120                                             p->pack_name, (uintmax_t)offset);
121                 }
122
123                 curpos = entries[i].offset;
124                 type = unpack_object_header(p, w_curs, &curpos, &size);
125                 unuse_pack(w_curs);
126
127                 if (type == OBJ_BLOB && big_file_threshold <= size) {
128                         /*
129                          * Let check_object_signature() check it with
130                          * the streaming interface; no point slurping
131                          * the data in-core only to discard.
132                          */
133                         data = NULL;
134                         data_valid = 0;
135                 } else {
136                         data = unpack_entry(p, entries[i].offset, &type, &size);
137                         data_valid = 1;
138                 }
139
140                 if (data_valid && !data)
141                         err = error("cannot unpack %s from %s at offset %"PRIuMAX"",
142                                     oid_to_hex(entries[i].oid.oid), p->pack_name,
143                                     (uintmax_t)entries[i].offset);
144                 else if (check_object_signature(entries[i].oid.oid, data, size, type_name(type)))
145                         err = error("packed %s from %s is corrupt",
146                                     oid_to_hex(entries[i].oid.oid), p->pack_name);
147                 else if (fn) {
148                         int eaten = 0;
149                         err |= fn(entries[i].oid.oid, type, size, data, &eaten);
150                         if (eaten)
151                                 data = NULL;
152                 }
153                 if (((base_count + i) & 1023) == 0)
154                         display_progress(progress, base_count + i);
155                 free(data);
156
157         }
158         display_progress(progress, base_count + i);
159         free(entries);
160
161         return err;
162 }
163
164 int verify_pack_index(struct packed_git *p)
165 {
166         off_t index_size;
167         const unsigned char *index_base;
168         git_hash_ctx ctx;
169         unsigned char hash[GIT_MAX_RAWSZ];
170         int err = 0;
171
172         if (open_pack_index(p))
173                 return error("packfile %s index not opened", p->pack_name);
174         index_size = p->index_size;
175         index_base = p->index_data;
176
177         /* Verify SHA1 sum of the index file */
178         the_hash_algo->init_fn(&ctx);
179         the_hash_algo->update_fn(&ctx, index_base, (unsigned int)(index_size - the_hash_algo->rawsz));
180         the_hash_algo->final_fn(hash, &ctx);
181         if (hashcmp(hash, index_base + index_size - the_hash_algo->rawsz))
182                 err = error("Packfile index for %s hash mismatch",
183                             p->pack_name);
184         return err;
185 }
186
187 int verify_pack(struct packed_git *p, verify_fn fn,
188                 struct progress *progress, uint32_t base_count)
189 {
190         int err = 0;
191         struct pack_window *w_curs = NULL;
192
193         err |= verify_pack_index(p);
194         if (!p->index_data)
195                 return -1;
196
197         err |= verify_packfile(p, &w_curs, fn, progress, base_count);
198         unuse_pack(&w_curs);
199
200         return err;
201 }