]> git.ipfire.org Git - thirdparty/git.git/blob - pack-check.c
Merge https://github.com/prati0100/git-gui
[thirdparty/git.git] / pack-check.c
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 + 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, type_name(type)))
146 err = error("packed %s from %s is corrupt",
147 oid_to_hex(&oid), p->pack_name);
148 else if (fn) {
149 int eaten = 0;
150 err |= fn(&oid, type, size, data, &eaten);
151 if (eaten)
152 data = NULL;
153 }
154 if (((base_count + i) & 1023) == 0)
155 display_progress(progress, base_count + i);
156 free(data);
157
158 }
159 display_progress(progress, base_count + i);
160 free(entries);
161
162 return err;
163 }
164
165 int verify_pack_index(struct packed_git *p)
166 {
167 off_t index_size;
168 const unsigned char *index_base;
169 git_hash_ctx ctx;
170 unsigned char hash[GIT_MAX_RAWSZ];
171 int err = 0;
172
173 if (open_pack_index(p))
174 return error("packfile %s index not opened", p->pack_name);
175 index_size = p->index_size;
176 index_base = p->index_data;
177
178 /* Verify SHA1 sum of the index file */
179 the_hash_algo->init_fn(&ctx);
180 the_hash_algo->update_fn(&ctx, index_base, (unsigned int)(index_size - the_hash_algo->rawsz));
181 the_hash_algo->final_fn(hash, &ctx);
182 if (!hasheq(hash, index_base + index_size - the_hash_algo->rawsz))
183 err = error("Packfile index for %s hash mismatch",
184 p->pack_name);
185 return err;
186 }
187
188 int verify_pack(struct repository *r, struct packed_git *p, verify_fn fn,
189 struct progress *progress, uint32_t base_count)
190 {
191 int err = 0;
192 struct pack_window *w_curs = NULL;
193
194 err |= verify_pack_index(p);
195 if (!p->index_data)
196 return -1;
197
198 err |= verify_packfile(r, p, &w_curs, fn, progress, base_count);
199 unuse_pack(&w_curs);
200
201 return err;
202 }