mirror of
https://github.com/git/git
synced 2024-10-30 14:03:28 +00:00
e876e74111
Signed-off-by: Johan Herland <johan@herland.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
140 lines
3.7 KiB
C
140 lines
3.7 KiB
C
#include "cache.h"
|
|
#include "tag.h"
|
|
|
|
/*
|
|
* A signature file has a very simple fixed format: four lines
|
|
* of "object <sha1>" + "type <typename>" + "tag <tagname>" +
|
|
* "tagger <committer>", followed by a blank line, a free-form tag
|
|
* message and a signature block that git itself doesn't care about,
|
|
* but that can be verified with gpg or similar.
|
|
*
|
|
* The first three lines are guaranteed to be at least 63 bytes:
|
|
* "object <sha1>\n" is 48 bytes, "type tag\n" at 9 bytes is the
|
|
* shortest possible type-line, and "tag .\n" at 6 bytes is the
|
|
* shortest single-character-tag line.
|
|
*/
|
|
|
|
/*
|
|
* We refuse to tag something we can't verify. Just because.
|
|
*/
|
|
static int verify_object(unsigned char *sha1, const char *expected_type)
|
|
{
|
|
int ret = -1;
|
|
enum object_type type;
|
|
unsigned long size;
|
|
void *buffer = read_sha1_file(sha1, &type, &size);
|
|
|
|
if (buffer) {
|
|
if (type == type_from_string(expected_type))
|
|
ret = check_sha1_signature(sha1, buffer, size, expected_type);
|
|
free(buffer);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
#ifdef NO_C99_FORMAT
|
|
#define PD_FMT "%d"
|
|
#else
|
|
#define PD_FMT "%td"
|
|
#endif
|
|
|
|
static int verify_tag(char *buffer, unsigned long size)
|
|
{
|
|
int typelen;
|
|
char type[20];
|
|
unsigned char sha1[20];
|
|
const char *object, *type_line, *tag_line, *tagger_line;
|
|
|
|
if (size < 64)
|
|
return error("wanna fool me ? you obviously got the size wrong !");
|
|
|
|
buffer[size] = 0;
|
|
|
|
/* Verify object line */
|
|
object = buffer;
|
|
if (memcmp(object, "object ", 7))
|
|
return error("char%d: does not start with \"object \"", 0);
|
|
|
|
if (get_sha1_hex(object + 7, sha1))
|
|
return error("char%d: could not get SHA1 hash", 7);
|
|
|
|
/* Verify type line */
|
|
type_line = object + 48;
|
|
if (memcmp(type_line - 1, "\ntype ", 6))
|
|
return error("char%d: could not find \"\\ntype \"", 47);
|
|
|
|
/* Verify tag-line */
|
|
tag_line = strchr(type_line, '\n');
|
|
if (!tag_line)
|
|
return error("char" PD_FMT ": could not find next \"\\n\"", type_line - buffer);
|
|
tag_line++;
|
|
if (memcmp(tag_line, "tag ", 4) || tag_line[4] == '\n')
|
|
return error("char" PD_FMT ": no \"tag \" found", tag_line - buffer);
|
|
|
|
/* Get the actual type */
|
|
typelen = tag_line - type_line - strlen("type \n");
|
|
if (typelen >= sizeof(type))
|
|
return error("char" PD_FMT ": type too long", type_line+5 - buffer);
|
|
|
|
memcpy(type, type_line+5, typelen);
|
|
type[typelen] = 0;
|
|
|
|
/* Verify that the object matches */
|
|
if (verify_object(sha1, type))
|
|
return error("char%d: could not verify object %s", 7, sha1_to_hex(sha1));
|
|
|
|
/* Verify the tag-name: we don't allow control characters or spaces in it */
|
|
tag_line += 4;
|
|
for (;;) {
|
|
unsigned char c = *tag_line++;
|
|
if (c == '\n')
|
|
break;
|
|
if (c > ' ')
|
|
continue;
|
|
return error("char" PD_FMT ": could not verify tag name", tag_line - buffer);
|
|
}
|
|
|
|
/* Verify the tagger line */
|
|
tagger_line = tag_line;
|
|
|
|
if (memcmp(tagger_line, "tagger", 6) || (tagger_line[6] == '\n'))
|
|
return error("char" PD_FMT ": could not find \"tagger\"", tagger_line - buffer);
|
|
|
|
/* TODO: check for committer info + blank line? */
|
|
/* Also, the minimum length is probably + "tagger .", or 63+8=71 */
|
|
|
|
/* The actual stuff afterwards we don't care about.. */
|
|
return 0;
|
|
}
|
|
|
|
#undef PD_FMT
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
unsigned long size = 4096;
|
|
char *buffer = xmalloc(size);
|
|
unsigned char result_sha1[20];
|
|
|
|
if (argc != 1)
|
|
usage("git-mktag < signaturefile");
|
|
|
|
setup_git_directory();
|
|
|
|
if (read_pipe(0, &buffer, &size)) {
|
|
free(buffer);
|
|
die("could not read from stdin");
|
|
}
|
|
|
|
/* Verify it for some basic sanity: it needs to start with
|
|
"object <sha1>\ntype\ntagger " */
|
|
if (verify_tag(buffer, size) < 0)
|
|
die("invalid tag signature file");
|
|
|
|
if (write_sha1_file(buffer, size, tag_type, result_sha1) < 0)
|
|
die("unable to write tag file");
|
|
|
|
free(buffer);
|
|
|
|
printf("%s\n", sha1_to_hex(result_sha1));
|
|
return 0;
|
|
}
|