fast-export: handle all kinds of tag signatures

Currently the handle_tag() function in "builtin/fast-export.c" searches only for "\n-----BEGIN PGP SIGNATURE-----\n" in the tag message to find a tag signature. This doesn't handle all kinds of OpenPGP signatures as some can start with "-----BEGIN PGP MESSAGE-----" too, and this doesn't handle SSH and X.509 signatures either as they use "-----BEGIN SSH SIGNATURE-----" and "-----BEGIN SIGNED MESSAGE-----" respectively. To handle all these kinds of tag signatures supported by Git, let's use the parse_signed_buffer() function to properly find signatures in tag messages. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Christian Couder committed Oct 13, 2025 at 10:48 UTC 31f375c31c645f35b83427045cfef719f2e4301b
2 files changed +39 -4
builtin/fast-export.c
+3 -4
@@ -931,9 +931,8 @@ static void handle_tag(const char *name, struct tag *tag)
931
932 /* handle signed tags */
933 if (message) {
934 - const char *signature = strstr(message,
935 - "\n-----BEGIN PGP SIGNATURE-----\n");
936 - if (signature)
934 + size_t sig_offset = parse_signed_buffer(message, message_size);
935 + if (sig_offset < message_size)
936 switch (signed_tag_mode) {
937 case SIGN_ABORT:
938 die("encountered signed tag %s; use "
@@ -950,7 +949,7 @@ static void handle_tag(const char *name, struct tag *tag)
949 oid_to_hex(&tag->object.oid));
950 /* fallthru */
951 case SIGN_STRIP:
953 - message_size = signature + 1 - message;
952 + message_size = sig_offset;
953 break;
954 }
955 }
t/t9350-fast-export.sh
+36
@@ -279,6 +279,42 @@ test_expect_success 'signed-tags=warn-strip' '
279 test -s err
280 '
281
282 +test_expect_success GPGSM 'setup X.509 signed tag' '
283 + test_config gpg.format x509 &&
284 + test_config user.signingkey $GIT_COMMITTER_EMAIL &&
285 +
286 + git tag -s -m "X.509 signed tag" x509-signed $(git rev-parse HEAD) &&
287 + ANNOTATED_TAG_COUNT=$((ANNOTATED_TAG_COUNT + 1))
288 +'
289 +
290 +test_expect_success GPGSM 'signed-tags=verbatim with X.509' '
291 + git fast-export --signed-tags=verbatim x509-signed > output &&
292 + test_grep "SIGNED MESSAGE" output
293 +'
294 +
295 +test_expect_success GPGSM 'signed-tags=strip with X.509' '
296 + git fast-export --signed-tags=strip x509-signed > output &&
297 + test_grep ! "SIGNED MESSAGE" output
298 +'
299 +
300 +test_expect_success GPGSSH 'setup SSH signed tag' '
301 + test_config gpg.format ssh &&
302 + test_config user.signingkey "${GPGSSH_KEY_PRIMARY}" &&
303 +
304 + git tag -s -m "SSH signed tag" ssh-signed $(git rev-parse HEAD) &&
305 + ANNOTATED_TAG_COUNT=$((ANNOTATED_TAG_COUNT + 1))
306 +'
307 +
308 +test_expect_success GPGSSH 'signed-tags=verbatim with SSH' '
309 + git fast-export --signed-tags=verbatim ssh-signed > output &&
310 + test_grep "SSH SIGNATURE" output
311 +'
312 +
313 +test_expect_success GPGSSH 'signed-tags=strip with SSH' '
314 + git fast-export --signed-tags=strip ssh-signed > output &&
315 + test_grep ! "SSH SIGNATURE" output
316 +'
317 +
318 test_expect_success GPG 'set up signed commit' '
319
320 # Generate a commit with both "gpgsig" and "encoding" set, so