From bf96bcf5c873afb94e75193486f0006585a66eae Mon Sep 17 00:00:00 2001
From: Pekka Riikonen <priikone@silcnet.org>
Date: Mon, 12 Feb 2001 13:59:46 +0000
Subject: [PATCH] 	Created.

---
 lib/silccrypt/silcdh.h | 84 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)
 create mode 100644 lib/silccrypt/silcdh.h

diff --git a/lib/silccrypt/silcdh.h b/lib/silccrypt/silcdh.h
new file mode 100644
index 00000000..b0f20998
--- /dev/null
+++ b/lib/silccrypt/silcdh.h
@@ -0,0 +1,84 @@
+/*
+
+  silcdh.h
+
+  Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
+
+  Copyright (C) 2001 Pekka Riikonen
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+  
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+*/
+/* PKCS #3 compliant Diffie Hellman key agreement protocol implementation.
+   This is used as part of SKE (SILC Key Exchange) protocol. */
+
+#ifndef SILCDH_H
+#define SILCDH_H
+
+#include "silcmp.h"
+#include "silcrng.h"
+
+/* Forward declaration of Diffie Hellman context */
+typedef struct SilcDHStruct *SilcDH;
+
+/* XXX Move to source file */
+/* Diffie Hellman context. This includes the DH parameters including the
+   negotiated key material. */
+struct SilcDHStruct {
+  SilcInt *g;             /* Global base (generator) */
+  SilcInt *p;		  /* Global prime (modulus) */
+  SilcInt *my_x;       	  /* x, My private value (random) */
+  SilcInt *my_y;       	  /* y, My public value (y = g ^ x mod p) */
+  SilcInt *your_y;	  /* y', Your public value (y' = g ^ x' mod p) */
+  SilcInt *z;		  /* The computed secret key (z = y' ^ x mod p) */
+
+  SilcRng rng;		  /* RNG */
+};
+
+/* Allocate DH context. The `rng' must be initialized random number generator
+   context, the `g' is the public base generator used in the negotiation and
+   the `p' is the public prime used in the negotiation. Returns NULL on error
+   or allocated DH context on success. */
+SilcDH silc_dh_alloc(SilcRng rng, SilcInt *g, SilcInt *p);
+
+/* Frees the DH context. Does not free the RNG context given in the 
+   allocation. Frees all the allocated data inside the DH context. */
+void silc_dh_free(SilcDH dh);
+
+/* Generates random private value `x' such that 1 < x < n. The rnd sent
+   as argument must be initialized. Returns FALSE if the random number
+   could not be generated. Returns the generated value into `x' pointer
+   sent as argument, unless the `x' is NULL. The returned `x' must no be
+   freed by the caller. */
+int silc_dh_generate_private(SilcDH dh, SilcInt **x);
+
+/* Computes the public key y = g ^ x mod p, and returns it to the `y'
+   pointer sent as argument, unless the `y' is NULL. Returns FALSE if
+   the computation could not be performed. The returned `y' must not be
+   freed by the caller. */
+int silc_dh_compute_public(SilcDH dh, SilcInt **y);
+
+/* Sets the remote end's public value y' into the DH context. This must be
+   done before computing the secret key. Returns FALSE on error. */
+int silc_dh_set_remote_public(SilcDH dh, SilcInt **y);
+
+/* Computes the secret key z = y' ^ x mod p, and returns the key to the
+   `z' pointer sent as argument, unless the `z' is NULL. Returns FALSE if
+   the computation could not be performed. The returned `z' must not be
+   freed by the caller. */
+int silc_dh_compute_key(SilcDH dh, SilcInt **z);
+
+/* Same as above but returns the computed secret key as octet binary
+   string. */
+int silc_dh_compute_key_data(SilcDH dh, unsigned char **z, 
+			     unsigned int *z_len);
+
+#endif
-- 
2.24.0