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Commit | Line | Data |
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ec4465ad | 1 | #include "cache.h" |
8e440259 | 2 | #include "tag.h" |
ec4465ad LT |
3 | |
4 | /* | |
446c6fae RJ |
5 | * A signature file has a very simple fixed format: four lines |
6 | * of "object <sha1>" + "type <typename>" + "tag <tagname>" + | |
7 | * "tagger <committer>", followed by a blank line, a free-form tag | |
8 | * message and a signature block that git itself doesn't care about, | |
9 | * but that can be verified with gpg or similar. | |
ec4465ad LT |
10 | * |
11 | * The first three lines are guaranteed to be at least 63 bytes: | |
12 | * "object <sha1>\n" is 48 bytes, "type tag\n" at 9 bytes is the | |
13 | * shortest possible type-line, and "tag .\n" at 6 bytes is the | |
14 | * shortest single-character-tag line. | |
15 | * | |
16 | * We also artificially limit the size of the full object to 8kB. | |
17 | * Just because I'm a lazy bastard, and if you can't fit a signature | |
18 | * in that size, you're doing something wrong. | |
19 | */ | |
20 | ||
a9486b02 | 21 | /* Some random size */ |
ec4465ad LT |
22 | #define MAXSIZE (8192) |
23 | ||
24 | /* | |
25 | * We refuse to tag something we can't verify. Just because. | |
26 | */ | |
27 | static int verify_object(unsigned char *sha1, const char *expected_type) | |
28 | { | |
29 | int ret = -1; | |
91d7b8af NP |
30 | char type[100]; |
31 | unsigned long size; | |
32 | void *buffer = read_sha1_file(sha1, type, &size); | |
ec4465ad | 33 | |
91d7b8af NP |
34 | if (buffer) { |
35 | if (!strcmp(type, expected_type)) | |
36 | ret = check_sha1_signature(sha1, buffer, size, type); | |
37 | free(buffer); | |
ec4465ad LT |
38 | } |
39 | return ret; | |
40 | } | |
41 | ||
579d1fbf RJ |
42 | #ifdef NO_C99_FORMAT |
43 | #define PD_FMT "%d" | |
44 | #else | |
45 | #define PD_FMT "%td" | |
46 | #endif | |
47 | ||
ec4465ad LT |
48 | static int verify_tag(char *buffer, unsigned long size) |
49 | { | |
50 | int typelen; | |
51 | char type[20]; | |
52 | unsigned char sha1[20]; | |
c818566d | 53 | const char *object, *type_line, *tag_line, *tagger_line; |
ec4465ad | 54 | |
e7332f96 | 55 | if (size < 64) |
446c6fae | 56 | return error("wanna fool me ? you obviously got the size wrong !"); |
cfba0459 | 57 | |
ec4465ad LT |
58 | buffer[size] = 0; |
59 | ||
60 | /* Verify object line */ | |
61 | object = buffer; | |
62 | if (memcmp(object, "object ", 7)) | |
446c6fae | 63 | return error("char%d: does not start with \"object \"", 0); |
cfba0459 | 64 | |
ec4465ad | 65 | if (get_sha1_hex(object + 7, sha1)) |
446c6fae | 66 | return error("char%d: could not get SHA1 hash", 7); |
ec4465ad LT |
67 | |
68 | /* Verify type line */ | |
69 | type_line = object + 48; | |
70 | if (memcmp(type_line - 1, "\ntype ", 6)) | |
446c6fae | 71 | return error("char%d: could not find \"\\ntype \"", 47); |
ec4465ad LT |
72 | |
73 | /* Verify tag-line */ | |
74 | tag_line = strchr(type_line, '\n'); | |
75 | if (!tag_line) | |
579d1fbf | 76 | return error("char" PD_FMT ": could not find next \"\\n\"", type_line - buffer); |
ec4465ad LT |
77 | tag_line++; |
78 | if (memcmp(tag_line, "tag ", 4) || tag_line[4] == '\n') | |
579d1fbf | 79 | return error("char" PD_FMT ": no \"tag \" found", tag_line - buffer); |
ec4465ad LT |
80 | |
81 | /* Get the actual type */ | |
82 | typelen = tag_line - type_line - strlen("type \n"); | |
83 | if (typelen >= sizeof(type)) | |
579d1fbf | 84 | return error("char" PD_FMT ": type too long", type_line+5 - buffer); |
cfba0459 | 85 | |
ec4465ad LT |
86 | memcpy(type, type_line+5, typelen); |
87 | type[typelen] = 0; | |
88 | ||
89 | /* Verify that the object matches */ | |
ec4465ad | 90 | if (verify_object(sha1, type)) |
446c6fae | 91 | return error("char%d: could not verify object %s", 7, sha1_to_hex(sha1)); |
ec4465ad LT |
92 | |
93 | /* Verify the tag-name: we don't allow control characters or spaces in it */ | |
94 | tag_line += 4; | |
95 | for (;;) { | |
96 | unsigned char c = *tag_line++; | |
97 | if (c == '\n') | |
98 | break; | |
99 | if (c > ' ') | |
100 | continue; | |
579d1fbf | 101 | return error("char" PD_FMT ": could not verify tag name", tag_line - buffer); |
ec4465ad LT |
102 | } |
103 | ||
c818566d EB |
104 | /* Verify the tagger line */ |
105 | tagger_line = tag_line; | |
106 | ||
107 | if (memcmp(tagger_line, "tagger", 6) || (tagger_line[6] == '\n')) | |
579d1fbf | 108 | return error("char" PD_FMT ": could not find \"tagger\"", tagger_line - buffer); |
446c6fae RJ |
109 | |
110 | /* TODO: check for committer info + blank line? */ | |
111 | /* Also, the minimum length is probably + "tagger .", or 63+8=71 */ | |
c818566d | 112 | |
ec4465ad LT |
113 | /* The actual stuff afterwards we don't care about.. */ |
114 | return 0; | |
115 | } | |
116 | ||
579d1fbf RJ |
117 | #undef PD_FMT |
118 | ||
ec4465ad LT |
119 | int main(int argc, char **argv) |
120 | { | |
e7332f96 | 121 | unsigned long size = 4096; |
2d7320d0 | 122 | char *buffer = xmalloc(size); |
ec4465ad LT |
123 | unsigned char result_sha1[20]; |
124 | ||
125 | if (argc != 1) | |
15e593e4 | 126 | usage("git-mktag < signaturefile"); |
ec4465ad | 127 | |
53228a5f JH |
128 | setup_git_directory(); |
129 | ||
e7332f96 BE |
130 | if (read_pipe(0, &buffer, &size)) { |
131 | free(buffer); | |
132 | die("could not read from stdin"); | |
b97e3dfa | 133 | } |
ec4465ad | 134 | |
a9486b02 PR |
135 | /* Verify it for some basic sanity: it needs to start with |
136 | "object <sha1>\ntype\ntagger " */ | |
ec4465ad LT |
137 | if (verify_tag(buffer, size) < 0) |
138 | die("invalid tag signature file"); | |
139 | ||
8e440259 | 140 | if (write_sha1_file(buffer, size, tag_type, result_sha1) < 0) |
ec4465ad | 141 | die("unable to write tag file"); |
e7332f96 BE |
142 | |
143 | free(buffer); | |
144 | ||
ec4465ad LT |
145 | printf("%s\n", sha1_to_hex(result_sha1)); |
146 | return 0; | |
147 | } |