verify-commit by default displays human-readable output on standard
error. However, it can also be useful to get access to the raw gpg
status information, which is machine-readable, allowing automated
implementation of signing policy. Add a --raw option to make
verify-commit produce the gpg status information on standard error
instead of the human-readable format.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code to handle printing of signature data from a struct
signature_check is very similar between verify-commit and verify-tag.
Place this in a single function. verify-tag retains its special case
behavior of printing the tag even when no valid signature is found.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
verify-commit and verify-tag both share a central codepath for verifying
commits: check_signature. However, verify-tag exited successfully for
untrusted signature, while verify-commit exited unsuccessfully.
Centralize this signature check and make verify-commit adopt the older
verify-tag behavior. This behavior is more logical anyway, as the
signature is in fact valid, whether or not there's a path of trust to
the author.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
verify-tag was executing an entirely different codepath than
verify-commit, except for the underlying verify_signed_buffer. Move
much of the code from check_commit_signature to a generic
check_signature function and adjust both codepaths to call it.
Update verify-tag to explicitly output the signature text, as we now
call verify_signed_buffer with strbufs to catch the output, which
prevents it from being printed automatically.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Our signed-tag objects set the standard format used by Git to store
GPG-signed payload (i.e. the payload followed by its detached
signature) [*1*], and it made sense to have a helper to find the
boundary between the payload and its signature in tag.c back then.
Newer code added later to parse other kinds of objects that learned
to use the same format to store GPG-signed payload (e.g. signed
commits), however, kept using the helper from the same location.
Move it to gpg-interface; the helper is no longer about signed tag,
but it is how our code and data interact with GPG.
[Reference]
*1* http://thread.gmane.org/gmane.linux.kernel/297998/focus=1383
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Earlier, ffb6d7d5 (Move commit GPG signature verification to
commit.c, 2013-03-31) moved this helper that used to be in pretty.c
(i.e. the output code path) to commit.c for better reusability.
It was a good first step in the right direction, but still suffers
from a myopic view that commits will be the only thing we would ever
want to sign---we would actually want to be able to reuse it even
wider.
The function interprets what GPG said; gpg-interface is obviously a
better place. Move it there.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In contrast to tag signatures, commit signatures are put into the
header, that is between the other header parts and commit messages.
Provide access to the commit content sans the signature, which is the
payload that is actually signed. Commit signature verification does the
parsing anyways, and callers may wish to act on or display the commit
object sans the signature.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The struct has been growing members whose malloced memory needs to be
freed. Do this with one helper function so that no malloced memory shall
be left unfreed.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When --verify-signatures is specified, abort the merge in case a good
GPG signature from an untrusted key is encountered.
Signed-off-by: Sebastian Götte <jaseg@physik-pool.tu-berlin.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Currently, verify_signed_buffer() returns the user facing output only.
Allow callers to request the status output also.
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This mostly moves existing code from builtin/tag.c (for signing)
and builtin/verify-tag.c (for verifying) to a new gpg-interface.c
file to provide a more generic library interface.
- sign_buffer() takes a payload strbuf, a signature strbuf, and a signing
key, runs "gpg" to produce a detached signature for the payload, and
appends it to the signature strbuf. The contents of a signed tag that
concatenates the payload and the detached signature can be produced by
giving the same strbuf as payload and signature strbuf.
- verify_signed_buffer() takes a payload and a detached signature as
<ptr, len> pairs, and runs "gpg --verify" to see if the payload matches
the signature. It can optionally capture the output from GPG to allow
the callers to pretty-print it in a way more suitable for their
contexts.
"verify-tag" (aka "tag -v") used to save the whole tag contents as if it
is a detached signature, and fed gpg the payload part of the tag. It
relied on gpg to fail when the given tag is not signed but just is
annotated. The updated run_gpg_verify() function detects the lack of
detached signature in the input, and errors out without bothering "gpg".
Signed-off-by: Junio C Hamano <gitster@pobox.com>
brian m. carlson
Junio C Hamano
Michael J Gruber
Sebastian Götte