Merge branch 'gm/signature-format-doc'
Doc update.
* gm/signature-format-doc:
signature-format.txt: note SSH and X.509 signature delimiters
diff --git a/Documentation/config/gpg.txt b/Documentation/config/gpg.txt
index 86f6308..37e2831 100644
--- a/Documentation/config/gpg.txt
+++ b/Documentation/config/gpg.txt
@@ -12,6 +12,9 @@
gpg.format::
Specifies which key format to use when signing with `--gpg-sign`.
Default is "openpgp". Other possible values are "x509", "ssh".
++
+See linkgit:gitformat-signature[5] for the signature format, which differs
+based on the selected `gpg.format`.
gpg.<format>.program::
Use this to customize the program used for the signing format you
diff --git a/Documentation/gitformat-signature.txt b/Documentation/gitformat-signature.txt
index d8e3eb1..d4d3a31 100644
--- a/Documentation/gitformat-signature.txt
+++ b/Documentation/gitformat-signature.txt
@@ -17,12 +17,24 @@
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
