Merge branch 'gm/signature-format-doc'

[thirdparty/git.git] / Documentation / gitformat-signature.txt

diff --git a/Documentation/gitformat-signature.txt b/Documentation/gitformat-signature.txt
index d8e3eb1bac316db170047285e0e094f29ec9cfd1..d4d3a31f03541199f7e65feb80b2c713f217573d 100644 (file)
--- a/Documentation/gitformat-signature.txt
+++ b/Documentation/gitformat-signature.txt
@@ -17,12 +17,24 @@ DESCRIPTION
 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.
+calls an external program to obtain a detached signature for the payload
+(`gpg -bsa` in the case of PGP signatures), 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`.
+Signatures begin with an "ASCII Armor" header line and end with a tail line,
+which differ depending on signature type (as selected by `gpg.format`, see
+linkgit:git-config[1]). These are, for `gpg.format` values:
+
+`gpg` (PGP)::
+       `-----BEGIN PGP SIGNATURE-----` and `-----END PGP SIGNATURE-----`.
+       Or, if gpg is told to produce RFC1991 signatures,
+       `-----BEGIN PGP MESSAGE-----` and `-----END PGP MESSAGE-----`
+
+`ssh` (SSH)::
+       `-----BEGIN SSH SIGNATURE-----` and `-----END SSH SIGNATURE-----`
+
+`x509` (X.509)::
+       `-----BEGIN SIGNED MESSAGE-----` and `-----END SIGNED MESSAGE-----`
 
 Signatures sometimes appear as a part of the normal payload
 (e.g. a signed tag has the signature block appended after the payload