+.It sign Op Ar filename
+Sign a file with the local node's private key.
+If no
+.Ar filename
+is given, the file is read from standard input.
+The signed file is written to standard output.
+.It verify Ar name Op Ar filename
+Check the signature of a file against a node's public key.
+The
+.Ar name
+of the node must be given,
+or can be
+.Li .
+to check against the local node's public key, or
+.Li *
+to allow a signature from any node whose public key is known.
+If no
+.Ar filename
+is given, the file is read from standard input.
+If the verification is succesful,
+a copy of the input with the signature removed is written to standard output,
+and the exit code will be zero.
+If the verification failed,
+nothing will be written to standard output, and the exit code will be non-zero.