summaryrefslogtreecommitdiff
path: root/pack-check.c
blob: 054b0131e9756f8bb98556a62179c2f1c232e2e5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
#include "cache.h"
#include "pack.h"

static int verify_packfile(struct packed_git *p)
{
	unsigned long index_size = p->index_size;
	void *index_base = p->index_base;
	SHA_CTX ctx;
	unsigned char sha1[20];
	unsigned long pack_size = p->pack_size;
	void *pack_base;
	struct pack_header *hdr;
	int nr_objects, err, i;

	/* Header consistency check */
	hdr = p->pack_base;
	if (hdr->hdr_signature != htonl(PACK_SIGNATURE))
		return error("Packfile signature mismatch", p->pack_name);
	if (hdr->hdr_version != htonl(PACK_VERSION))
		return error("Packfile version %d different from ours %d",
			     ntohl(hdr->hdr_version), PACK_VERSION);
	nr_objects = ntohl(hdr->hdr_entries);
	if (num_packed_objects(p) != nr_objects)
		return error("Packfile claims to have %d objects, "
			     "while idx size expects %d", nr_objects,
			     num_packed_objects(p));

	SHA1_Init(&ctx);
	pack_base = p->pack_base;
	SHA1_Update(&ctx, pack_base, pack_size - 20);
	SHA1_Final(sha1, &ctx);
	if (memcmp(sha1, index_base + index_size - 40, 20))
		return error("Packfile %s SHA1 mismatch with idx",
			     p->pack_name);
	if (memcmp(sha1, pack_base + pack_size - 20, 20))
		return error("Packfile %s SHA1 mismatch with itself",
			     p->pack_name);

	/* Make sure everything reachable from idx is valid.  Since we
	 * have verified that nr_objects matches between idx and pack,
	 * we do not do scan-streaming check on the pack file.
	 */
	for (i = err = 0; i < nr_objects; i++) {
		unsigned char sha1[20];
		struct pack_entry e;
		void *data;
		char type[20];
		unsigned long size;

		if (nth_packed_object_sha1(p, i, sha1))
			die("internal error pack-check nth-packed-object");
		if (!find_pack_entry_one(sha1, &e, p))
			die("internal error pack-check find-pack-entry-one");
		data = unpack_entry_gently(&e, type, &size);
		if (!data) {
			err = error("cannot unpack %s from %s",
				    sha1_to_hex(sha1), p->pack_name);
			continue;
		}
		if (check_sha1_signature(sha1, data, size, type)) {
			err = error("packed %s from %s is corrupt",
				    sha1_to_hex(sha1), p->pack_name);
			free(data);
			continue;
		}
		free(data);
	}

	return err;
}


static void show_pack_info(struct packed_git *p)
{
	struct pack_header *hdr;
	int nr_objects, i;

	hdr = p->pack_base;
	nr_objects = ntohl(hdr->hdr_entries);

	for (i = 0; i < nr_objects; i++) {
		unsigned char sha1[20], base_sha1[20];
		struct pack_entry e;
		char type[20];
		unsigned long size;
		unsigned long store_size;
		int delta_chain_length;

		if (nth_packed_object_sha1(p, i, sha1))
			die("internal error pack-check nth-packed-object");
		if (!find_pack_entry_one(sha1, &e, p))
			die("internal error pack-check find-pack-entry-one");

		packed_object_info_detail(&e, type, &size, &store_size,
					  &delta_chain_length,
					  base_sha1);
		printf("%s ", sha1_to_hex(sha1));
		if (!delta_chain_length)
			printf("%-6s %lu %u\n", type, size, e.offset);
		else
			printf("%-6s %lu %u %d %s\n", type, size, e.offset,
			       delta_chain_length, sha1_to_hex(base_sha1));
	}

}

int verify_pack(struct packed_git *p, int verbose)
{
	unsigned long index_size = p->index_size;
	void *index_base = p->index_base;
	SHA_CTX ctx;
	unsigned char sha1[20];
	int ret;

	ret = 0;
	/* Verify SHA1 sum of the index file */
	SHA1_Init(&ctx);
	SHA1_Update(&ctx, index_base, index_size - 20);
	SHA1_Final(sha1, &ctx);
	if (memcmp(sha1, index_base + index_size - 20, 20))
		ret = error("Packfile index for %s SHA1 mismatch",
			    p->pack_name);

	if (!ret) {
		/* Verify pack file */
		use_packed_git(p);
		ret = verify_packfile(p);
		unuse_packed_git(p);
	}

	if (verbose) {
		if (ret)
			printf("%s: bad\n", p->pack_name);
		else {
			use_packed_git(p);
			show_pack_info(p);
			unuse_packed_git(p);
			printf("%s: ok\n", p->pack_name);
		}
	}

	return ret;
}