.SS diffie-hellman
.PP
\fBdiffie-hellman(\fIMODULUS\fB, \fIGENERATOR\fR[\fB, \fICHECK\fR]\fB)\fR => \fIdh closure\fR
-.TP
-.I MODULUS
+.br
+\fBdiffie-hellman(\fIDICT\fB)\fR => \fIdh closure\fR
+Defines a Diffie\(enHellman group which uses
+traditional Diffie\(enHellman modulo a large prime number.
+Arguments may be provided
+either as positional arguments
+or in a dictionary.
+Dictionary keys are described below;
+those keys which correspond with positional arguments
+are mentioned in the individual descriptions.
+.TP
+.B p
String.
The prime modulus \fIp\fR in hex.
+Corresponds to the
+.I MODULUS
+argument.
.TP
-.I GENERATOR
+.B g
String.
The generator \fIg\fR in hex.
+Corresponds to the
+.I GENERATOR
+argument.
.TP
-.I CHECK
+.B check
Boolean.
If \fBtrue\fR (the default) then check if \fIp\fR is prime.
+Corresponds to the
+.I CHECK
+argument.
.PP
A \fIdh closure\fR defines a group to be used for key exchange.