progs/*.1: Mention the default hash for `ed25519',

[catacomb] / progs / key.1

diff --git a/progs/key.1 b/progs/key.1
index abd399d..0ffd076 100644 (file)
--- a/progs/key.1
+++ b/progs/key.1
@@ -472,6 +472,14 @@ using a passphrase.
 Suppresses the progress indication which is usually generated while
 time-consuming key generation tasks are being performed.
 .TP
+.BI "\-E, \-\-public-exponent"
+Set the public exponent for RSA keys.
+The default is 65537,
+because this seems to be the overwhelmingly popular choice
+among practitioners
+and because it was the exponent used before this option was introduced.
+The value 3 is fine unless you use a completely terrible padding scheme.
+.TP
 .BI "\-L, \-\-lim-lee"
 When generating Diffie\(enHellman parameters, generate a Lim\(enLee
 prime rather than a random (or safe) prime.  See the details on
@@ -846,6 +854,29 @@ the public point is then
 \(mu
 .IR G .
 .TP
+.B x25519
+Generate a private scalar and a corresponding public point on the
+(Montgomery-form) Curve25519 elliptic curve.
+The scalar is simply a random 256-bit string;
+the public key is the
+.IR x -coordinate
+of the corresponding point.
+.TP
+.B x448
+Generate a private scalar and a corresponding public point on the
+(Montgomery-form) Ed448-Goldilocks elliptic curve.
+The scalar is simply a random 256-bit string;
+the public key is the
+.IR x -coordinate
+of the corresponding point.
+.TP
+.B ed25519
+Generate a private key and a corresponding public point on the
+(twisted Edwards-form) Curve25519 elliptic curve.
+The private key is simply a random 256-bit string,
+from which a scalar and secret prefix are derived;
+the public key is the compressed form of the corresponding point.
+.TP
 .B empty
 Generate an empty key, with trivial contents.
 This is useful as a `parameters' key,