2016-06-17 15:46:08 +08:00
|
|
|
Git signature format
|
|
|
|
|
====================
|
|
|
|
|
|
|
|
|
|
== Overview
|
|
|
|
|
|
|
|
|
|
Git uses cryptographic signatures in various places, currently objects (tags,
|
|
|
|
|
commits, mergetags) and transactions (pushes). In every case, the command which
|
|
|
|
|
is about to create an object or transaction determines a payload from that,
|
|
|
|
|
calls gpg to obtain a detached signature for the payload (`gpg -bsa`) and
|
|
|
|
|
embeds the signature into the object or transaction.
|
|
|
|
|
|
|
|
|
|
Signatures always begin with `-----BEGIN PGP SIGNATURE-----`
|
|
|
|
|
and end with `-----END PGP SIGNATURE-----`, unless gpg is told to
|
|
|
|
|
produce RFC1991 signatures which use `MESSAGE` instead of `SIGNATURE`.
|
|
|
|
|
|
|
|
|
|
The signed payload and the way the signature is embedded depends
|
|
|
|
|
on the type of the object resp. transaction.
|
2016-06-17 15:46:09 +08:00
|
|
|
|
|
|
|
|
== Tag signatures
|
|
|
|
|
|
|
|
|
|
- created by: `git tag -s`
|
|
|
|
|
- payload: annotated tag object
|
|
|
|
|
- embedding: append the signature to the unsigned tag object
|
|
|
|
|
- example: tag `signedtag` with subject `signed tag`
|
|
|
|
|
|
|
|
|
|
----
|
|
|
|
|
object 04b871796dc0420f8e7561a895b52484b701d51a
|
|
|
|
|
type commit
|
|
|
|
|
tag signedtag
|
|
|
|
|
tagger C O Mitter <committer@example.com> 1465981006 +0000
|
|
|
|
|
|
|
|
|
|
signed tag
|
|
|
|
|
|
|
|
|
|
signed tag message body
|
|
|
|
|
-----BEGIN PGP SIGNATURE-----
|
|
|
|
|
Version: GnuPG v1
|
|
|
|
|
|
|
|
|
|
iQEcBAABAgAGBQJXYRhOAAoJEGEJLoW3InGJklkIAIcnhL7RwEb/+QeX9enkXhxn
|
|
|
|
|
rxfdqrvWd1K80sl2TOt8Bg/NYwrUBw/RWJ+sg/hhHp4WtvE1HDGHlkEz3y11Lkuh
|
|
|
|
|
8tSxS3qKTxXUGozyPGuE90sJfExhZlW4knIQ1wt/yWqM+33E9pN4hzPqLwyrdods
|
|
|
|
|
q8FWEqPPUbSJXoMbRPw04S5jrLtZSsUWbRYjmJCHzlhSfFWW4eFd37uquIaLUBS0
|
|
|
|
|
rkC3Jrx7420jkIpgFcTI2s60uhSQLzgcCwdA2ukSYIRnjg/zDkj8+3h/GaROJ72x
|
|
|
|
|
lZyI6HWixKJkWw8lE9aAOD9TmTW9sFJwcVAzmAuFX2kUreDUKMZduGcoRYGpD7E=
|
|
|
|
|
=jpXa
|
|
|
|
|
-----END PGP SIGNATURE-----
|
|
|
|
|
----
|
|
|
|
|
|
|
|
|
|
- verify with: `git verify-tag [-v]` or `git tag -v`
|
|
|
|
|
|
|
|
|
|
----
|
|
|
|
|
gpg: Signature made Wed Jun 15 10:56:46 2016 CEST using RSA key ID B7227189
|
|
|
|
|
gpg: Good signature from "Eris Discordia <discord@example.net>"
|
|
|
|
|
gpg: WARNING: This key is not certified with a trusted signature!
|
|
|
|
|
gpg: There is no indication that the signature belongs to the owner.
|
|
|
|
|
Primary key fingerprint: D4BE 2231 1AD3 131E 5EDA 29A4 6109 2E85 B722 7189
|
|
|
|
|
object 04b871796dc0420f8e7561a895b52484b701d51a
|
|
|
|
|
type commit
|
|
|
|
|
tag signedtag
|
|
|
|
|
tagger C O Mitter <committer@example.com> 1465981006 +0000
|
|
|
|
|
|
|
|
|
|
signed tag
|
|
|
|
|
|
|
|
|
|
signed tag message body
|
|
|
|
|
----
|
2016-06-17 15:46:10 +08:00
|
|
|
|
|
|
|
|
== Commit signatures
|
|
|
|
|
|
|
|
|
|
- created by: `git commit -S`
|
|
|
|
|
- payload: commit object
|
|
|
|
|
- embedding: header entry `gpgsig`
|
|
|
|
|
(content is preceded by a space)
|
|
|
|
|
- example: commit with subject `signed commit`
|
|
|
|
|
|
|
|
|
|
----
|
|
|
|
|
tree eebfed94e75e7760540d1485c740902590a00332
|
|
|
|
|
parent 04b871796dc0420f8e7561a895b52484b701d51a
|
|
|
|
|
author A U Thor <author@example.com> 1465981137 +0000
|
|
|
|
|
committer C O Mitter <committer@example.com> 1465981137 +0000
|
|
|
|
|
gpgsig -----BEGIN PGP SIGNATURE-----
|
|
|
|
|
Version: GnuPG v1
|
|
|
|
|
|
|
|
|
|
iQEcBAABAgAGBQJXYRjRAAoJEGEJLoW3InGJ3IwIAIY4SA6GxY3BjL60YyvsJPh/
|
|
|
|
|
HRCJwH+w7wt3Yc/9/bW2F+gF72kdHOOs2jfv+OZhq0q4OAN6fvVSczISY/82LpS7
|
|
|
|
|
DVdMQj2/YcHDT4xrDNBnXnviDO9G7am/9OE77kEbXrp7QPxvhjkicHNwy2rEflAA
|
|
|
|
|
zn075rtEERDHr8nRYiDh8eVrefSO7D+bdQ7gv+7GsYMsd2auJWi1dHOSfTr9HIF4
|
|
|
|
|
HJhWXT9d2f8W+diRYXGh4X0wYiGg6na/soXc+vdtDYBzIxanRqjg8jCAeo1eOTk1
|
|
|
|
|
EdTwhcTZlI0x5pvJ3H0+4hA2jtldVtmPM4OTB0cTrEWBad7XV6YgiyuII73Ve3I=
|
|
|
|
|
=jKHM
|
|
|
|
|
-----END PGP SIGNATURE-----
|
|
|
|
|
|
|
|
|
|
signed commit
|
|
|
|
|
|
|
|
|
|
signed commit message body
|
|
|
|
|
----
|
|
|
|
|
|
|
|
|
|
- verify with: `git verify-commit [-v]` (or `git show --show-signature`)
|
|
|
|
|
|
|
|
|
|
----
|
|
|
|
|
gpg: Signature made Wed Jun 15 10:58:57 2016 CEST using RSA key ID B7227189
|
|
|
|
|
gpg: Good signature from "Eris Discordia <discord@example.net>"
|
|
|
|
|
gpg: WARNING: This key is not certified with a trusted signature!
|
|
|
|
|
gpg: There is no indication that the signature belongs to the owner.
|
|
|
|
|
Primary key fingerprint: D4BE 2231 1AD3 131E 5EDA 29A4 6109 2E85 B722 7189
|
|
|
|
|
tree eebfed94e75e7760540d1485c740902590a00332
|
|
|
|
|
parent 04b871796dc0420f8e7561a895b52484b701d51a
|
|
|
|
|
author A U Thor <author@example.com> 1465981137 +0000
|
|
|
|
|
committer C O Mitter <committer@example.com> 1465981137 +0000
|
|
|
|
|
|
|
|
|
|
signed commit
|
|
|
|
|
|
|
|
|
|
signed commit message body
|
|
|
|
|
----
|
2016-06-17 15:46:11 +08:00
|
|
|
|
|
|
|
|
== Mergetag signatures
|
|
|
|
|
|
|
|
|
|
- created by: `git merge` on signed tag
|
|
|
|
|
- payload/embedding: the whole signed tag object is embedded into
|
|
|
|
|
the (merge) commit object as header entry `mergetag`
|
|
|
|
|
- example: merge of the signed tag `signedtag` as above
|
|
|
|
|
|
|
|
|
|
----
|
|
|
|
|
tree c7b1cff039a93f3600a1d18b82d26688668c7dea
|
|
|
|
|
parent c33429be94b5f2d3ee9b0adad223f877f174b05d
|
|
|
|
|
parent 04b871796dc0420f8e7561a895b52484b701d51a
|
|
|
|
|
author A U Thor <author@example.com> 1465982009 +0000
|
|
|
|
|
committer C O Mitter <committer@example.com> 1465982009 +0000
|
|
|
|
|
mergetag object 04b871796dc0420f8e7561a895b52484b701d51a
|
|
|
|
|
type commit
|
|
|
|
|
tag signedtag
|
|
|
|
|
tagger C O Mitter <committer@example.com> 1465981006 +0000
|
|
|
|
|
|
|
|
|
|
signed tag
|
|
|
|
|
|
|
|
|
|
signed tag message body
|
|
|
|
|
-----BEGIN PGP SIGNATURE-----
|
|
|
|
|
Version: GnuPG v1
|
|
|
|
|
|
|
|
|
|
iQEcBAABAgAGBQJXYRhOAAoJEGEJLoW3InGJklkIAIcnhL7RwEb/+QeX9enkXhxn
|
|
|
|
|
rxfdqrvWd1K80sl2TOt8Bg/NYwrUBw/RWJ+sg/hhHp4WtvE1HDGHlkEz3y11Lkuh
|
|
|
|
|
8tSxS3qKTxXUGozyPGuE90sJfExhZlW4knIQ1wt/yWqM+33E9pN4hzPqLwyrdods
|
|
|
|
|
q8FWEqPPUbSJXoMbRPw04S5jrLtZSsUWbRYjmJCHzlhSfFWW4eFd37uquIaLUBS0
|
|
|
|
|
rkC3Jrx7420jkIpgFcTI2s60uhSQLzgcCwdA2ukSYIRnjg/zDkj8+3h/GaROJ72x
|
|
|
|
|
lZyI6HWixKJkWw8lE9aAOD9TmTW9sFJwcVAzmAuFX2kUreDUKMZduGcoRYGpD7E=
|
|
|
|
|
=jpXa
|
|
|
|
|
-----END PGP SIGNATURE-----
|
|
|
|
|
|
|
|
|
|
Merge tag 'signedtag' into downstream
|
|
|
|
|
|
|
|
|
|
signed tag
|
|
|
|
|
|
|
|
|
|
signed tag message body
|
|
|
|
|
|
|
|
|
|
# gpg: Signature made Wed Jun 15 08:56:46 2016 UTC using RSA key ID B7227189
|
|
|
|
|
# gpg: Good signature from "Eris Discordia <discord@example.net>"
|
|
|
|
|
# gpg: WARNING: This key is not certified with a trusted signature!
|
|
|
|
|
# gpg: There is no indication that the signature belongs to the owner.
|
|
|
|
|
# Primary key fingerprint: D4BE 2231 1AD3 131E 5EDA 29A4 6109 2E85 B722 7189
|
|
|
|
|
----
|
|
|
|
|
|
|
|
|
|
- verify with: verification is embedded in merge commit message by default,
|
|
|
|
|
alternatively with `git show --show-signature`:
|
|
|
|
|
|
|
|
|
|
----
|
|
|
|
|
commit 9863f0c76ff78712b6800e199a46aa56afbcbd49
|
|
|
|
|
merged tag 'signedtag'
|
|
|
|
|
gpg: Signature made Wed Jun 15 10:56:46 2016 CEST using RSA key ID B7227189
|
|
|
|
|
gpg: Good signature from "Eris Discordia <discord@example.net>"
|
|
|
|
|
gpg: WARNING: This key is not certified with a trusted signature!
|
|
|
|
|
gpg: There is no indication that the signature belongs to the owner.
|
|
|
|
|
Primary key fingerprint: D4BE 2231 1AD3 131E 5EDA 29A4 6109 2E85 B722 7189
|
|
|
|
|
Merge: c33429b 04b8717
|
|
|
|
|
Author: A U Thor <author@example.com>
|
|
|
|
|
Date: Wed Jun 15 09:13:29 2016 +0000
|
|
|
|
|
|
|
|
|
|
Merge tag 'signedtag' into downstream
|
|
|
|
|
|
|
|
|
|
signed tag
|
|
|
|
|
|
|
|
|
|
signed tag message body
|
|
|
|
|
|
|
|
|
|
# gpg: Signature made Wed Jun 15 08:56:46 2016 UTC using RSA key ID B7227189
|
|
|
|
|
# gpg: Good signature from "Eris Discordia <discord@example.net>"
|
|
|
|
|
# gpg: WARNING: This key is not certified with a trusted signature!
|
|
|
|
|
# gpg: There is no indication that the signature belongs to the owner.
|
|
|
|
|
# Primary key fingerprint: D4BE 2231 1AD3 131E 5EDA 29A4 6109 2E85 B722 7189
|
|
|
|
|
----
|
