Do not segfault verifying "lightweight" tags ok stsp@

tweak tag_test_create to detect the issue fixed in previous commit

add signer_id option to got.conf(5) Setting this option will cause 'got tag' to sign all created tags using the SSH key, unless overridden by the -s flag. ok stsp@

regress test SSH key revocations ok stsp@

in tests, verify that tag -V behaves like tag -l plus signature verification

remove parts of tag_create_ssh_signed which just duplicate the tag_create test

remove duplicate test_parseargs call spotted by op@

fix echo/printf order and actually run the test

whitespace fix

fix tag signing when the key file does not exist This should fail without creating any tag. Before, ssh-keygen(1) would print an error to stderr, but got would create an unsigned tag. ok op@

create and verify tags signed by SSH keys This adds a new -s flag to 'got tag' that specifies the signer identity (for example, a key file) of the tagger. The tag object will include a signature that validates each of the tag object headers and the tag message. Verifying these signed tags requires maintaining an allowed signers file which maps signer identities (i.e. the email address of the tagger) to SSH public keys. See ssh-keygen(1) for more details of the allowed signers file. After creating this file and providing the path to it in got.conf(5) using the allowed_signers option, tags may be verified using with 'got tag -V tag_name'. The return code will be non-zero if a signature fails to verify. ok stsp@

make it possible to show just one tag with 'got tag -l' suggested by jrick ok jrick jamsek

use test(1) -eq and -ne to compare integers, and reduce quoting This brings the rest of the regression test scripts in line with patch.sh.

display the requested object type when an object could not be found ok millert@

use the POSIX-compliant "date -u" command to return UTC time; ok stsp