about summary refs log tree commit diff
path: root/third_party/git/tag.c
blob: 1ed2684e45bd50d051ade60cc6b66c8c44fbed59 (plain) (blame)
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
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
#include "cache.h"
#include "tag.h"
#include "object-store.h"
#include "commit.h"
#include "tree.h"
#include "blob.h"
#include "alloc.h"
#include "gpg-interface.h"
#include "packfile.h"

const char *tag_type = "tag";

static int run_gpg_verify(const char *buf, unsigned long size, unsigned flags)
{
	struct signature_check sigc;
	size_t payload_size;
	int ret;

	memset(&sigc, 0, sizeof(sigc));

	payload_size = parse_signature(buf, size);

	if (size == payload_size) {
		if (flags & GPG_VERIFY_VERBOSE)
			write_in_full(1, buf, payload_size);
		return error("no signature found");
	}

	ret = check_signature(buf, payload_size, buf + payload_size,
				size - payload_size, &sigc);

	if (!(flags & GPG_VERIFY_OMIT_STATUS))
		print_signature_buffer(&sigc, flags);

	signature_check_clear(&sigc);
	return ret;
}

int gpg_verify_tag(const struct object_id *oid, const char *name_to_report,
		unsigned flags)
{
	enum object_type type;
	char *buf;
	unsigned long size;
	int ret;

	type = oid_object_info(the_repository, oid, NULL);
	if (type != OBJ_TAG)
		return error("%s: cannot verify a non-tag object of type %s.",
				name_to_report ?
				name_to_report :
				find_unique_abbrev(oid, DEFAULT_ABBREV),
				type_name(type));

	buf = read_object_file(oid, &type, &size);
	if (!buf)
		return error("%s: unable to read file.",
				name_to_report ?
				name_to_report :
				find_unique_abbrev(oid, DEFAULT_ABBREV));

	ret = run_gpg_verify(buf, size, flags);

	free(buf);
	return ret;
}

struct object *deref_tag(struct repository *r, struct object *o, const char *warn, int warnlen)
{
	struct object_id *last_oid = NULL;
	while (o && o->type == OBJ_TAG)
		if (((struct tag *)o)->tagged) {
			last_oid = &((struct tag *)o)->tagged->oid;
			o = parse_object(r, last_oid);
		} else {
			last_oid = NULL;
			o = NULL;
		}
	if (!o && warn) {
		if (last_oid && is_promisor_object(last_oid))
			return NULL;
		if (!warnlen)
			warnlen = strlen(warn);
		error("missing object referenced by '%.*s'", warnlen, warn);
	}
	return o;
}

struct object *deref_tag_noverify(struct object *o)
{
	while (o && o->type == OBJ_TAG) {
		o = parse_object(the_repository, &o->oid);
		if (o && o->type == OBJ_TAG && ((struct tag *)o)->tagged)
			o = ((struct tag *)o)->tagged;
		else
			o = NULL;
	}
	return o;
}

struct tag *lookup_tag(struct repository *r, const struct object_id *oid)
{
	struct object *obj = lookup_object(r, oid);
	if (!obj)
		return create_object(r, oid, alloc_tag_node(r));
	return object_as_type(obj, OBJ_TAG, 0);
}

static timestamp_t parse_tag_date(const char *buf, const char *tail)
{
	const char *dateptr;

	while (buf < tail && *buf++ != '>')
		/* nada */;
	if (buf >= tail)
		return 0;
	dateptr = buf;
	while (buf < tail && *buf++ != '\n')
		/* nada */;
	if (buf >= tail)
		return 0;
	/* dateptr < buf && buf[-1] == '\n', so parsing will stop at buf-1 */
	return parse_timestamp(dateptr, NULL, 10);
}

void release_tag_memory(struct tag *t)
{
	free(t->tag);
	t->tagged = NULL;
	t->object.parsed = 0;
	t->date = 0;
}

int parse_tag_buffer(struct repository *r, struct tag *item, const void *data, unsigned long size)
{
	struct object_id oid;
	char type[20];
	const char *bufptr = data;
	const char *tail = bufptr + size;
	const char *nl;

	if (item->object.parsed)
		return 0;

	if (item->tag) {
		/*
		 * Presumably left over from a previous failed parse;
		 * clear it out in preparation for re-parsing (we'll probably
		 * hit the same error, which lets us tell our current caller
		 * about the problem).
		 */
		FREE_AND_NULL(item->tag);
	}

	if (size < the_hash_algo->hexsz + 24)
		return -1;
	if (memcmp("object ", bufptr, 7) || parse_oid_hex(bufptr + 7, &oid, &bufptr) || *bufptr++ != '\n')
		return -1;

	if (!starts_with(bufptr, "type "))
		return -1;
	bufptr += 5;
	nl = memchr(bufptr, '\n', tail - bufptr);
	if (!nl || sizeof(type) <= (nl - bufptr))
		return -1;
	memcpy(type, bufptr, nl - bufptr);
	type[nl - bufptr] = '\0';
	bufptr = nl + 1;

	if (!strcmp(type, blob_type)) {
		item->tagged = (struct object *)lookup_blob(r, &oid);
	} else if (!strcmp(type, tree_type)) {
		item->tagged = (struct object *)lookup_tree(r, &oid);
	} else if (!strcmp(type, commit_type)) {
		item->tagged = (struct object *)lookup_commit(r, &oid);
	} else if (!strcmp(type, tag_type)) {
		item->tagged = (struct object *)lookup_tag(r, &oid);
	} else {
		return error("unknown tag type '%s' in %s",
			     type, oid_to_hex(&item->object.oid));
	}

	if (!item->tagged)
		return error("bad tag pointer to %s in %s",
			     oid_to_hex(&oid),
			     oid_to_hex(&item->object.oid));

	if (bufptr + 4 < tail && starts_with(bufptr, "tag "))
		; 		/* good */
	else
		return -1;
	bufptr += 4;
	nl = memchr(bufptr, '\n', tail - bufptr);
	if (!nl)
		return -1;
	item->tag = xmemdupz(bufptr, nl - bufptr);
	bufptr = nl + 1;

	if (bufptr + 7 < tail && starts_with(bufptr, "tagger "))
		item->date = parse_tag_date(bufptr, tail);
	else
		item->date = 0;

	item->object.parsed = 1;
	return 0;
}

int parse_tag(struct tag *item)
{
	enum object_type type;
	void *data;
	unsigned long size;
	int ret;

	if (item->object.parsed)
		return 0;
	data = read_object_file(&item->object.oid, &type, &size);
	if (!data)
		return error("Could not read %s",
			     oid_to_hex(&item->object.oid));
	if (type != OBJ_TAG) {
		free(data);
		return error("Object %s not a tag",
			     oid_to_hex(&item->object.oid));
	}
	ret = parse_tag_buffer(the_repository, item, data, size);
	free(data);
	return ret;
}

struct object_id *get_tagged_oid(struct tag *tag)
{
	if (!tag->tagged)
		die("bad tag");
	return &tag->tagged->oid;
}