--- /dev/null
+/* Copyright (c) 2015, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#ifndef OPENSSL_HEADER_CURVE25519_H
+#define OPENSSL_HEADER_CURVE25519_H
+
+#include <openssl/base.h>
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+
+// Curve25519.
+//
+// Curve25519 is an elliptic curve. See https://tools.ietf.org/html/rfc7748.
+
+
+// X25519.
+//
+// X25519 is the Diffie-Hellman primitive built from curve25519. It is
+// sometimes referred to as “curve25519”, but “X25519” is a more precise name.
+// See http://cr.yp.to/ecdh.html and https://tools.ietf.org/html/rfc7748.
+
+#define X25519_PRIVATE_KEY_LEN 32
+#define X25519_PUBLIC_VALUE_LEN 32
+#define X25519_SHARED_KEY_LEN 32
+
+// X25519_keypair sets |out_public_value| and |out_private_key| to a freshly
+// generated, public–private key pair.
+OPENSSL_EXPORT void X25519_keypair(uint8_t out_public_value[32],
+ uint8_t out_private_key[32]);
+
+// X25519 writes a shared key to |out_shared_key| that is calculated from the
+// given private key and the peer's public value. It returns one on success and
+// zero on error.
+//
+// Don't use the shared key directly, rather use a KDF and also include the two
+// public values as inputs.
+OPENSSL_EXPORT int X25519(uint8_t out_shared_key[32],
+ const uint8_t private_key[32],
+ const uint8_t peer_public_value[32]);
+
+// X25519_public_from_private calculates a Diffie-Hellman public value from the
+// given private key and writes it to |out_public_value|.
+OPENSSL_EXPORT void X25519_public_from_private(uint8_t out_public_value[32],
+ const uint8_t private_key[32]);
+
+
+// Ed25519.
+//
+// Ed25519 is a signature scheme using a twisted-Edwards curve that is
+// birationally equivalent to curve25519.
+//
+// Note that, unlike RFC 8032's formulation, our private key representation
+// includes a public key suffix to make multiple key signing operations with the
+// same key more efficient. The RFC 8032 key private key is referred to in this
+// implementation as the "seed" and is the first 32 bytes of our private key.
+
+#define ED25519_PRIVATE_KEY_LEN 64
+#define ED25519_PUBLIC_KEY_LEN 32
+#define ED25519_SIGNATURE_LEN 64
+
+// ED25519_keypair sets |out_public_key| and |out_private_key| to a freshly
+// generated, public–private key pair.
+OPENSSL_EXPORT void ED25519_keypair(uint8_t out_public_key[32],
+ uint8_t out_private_key[64]);
+
+// ED25519_sign sets |out_sig| to be a signature of |message_len| bytes from
+// |message| using |private_key|. It returns one on success or zero on
+// error.
+OPENSSL_EXPORT int ED25519_sign(uint8_t out_sig[64], const uint8_t *message,
+ size_t message_len,
+ const uint8_t private_key[64]);
+
+// ED25519_verify returns one iff |signature| is a valid signature, by
+// |public_key| of |message_len| bytes from |message|. It returns zero
+// otherwise.
+OPENSSL_EXPORT int ED25519_verify(const uint8_t *message, size_t message_len,
+ const uint8_t signature[64],
+ const uint8_t public_key[32]);
+
+// ED25519_keypair_from_seed calculates a public and private key from an
+// Ed25519 “seed”. Seed values are not exposed by this API (although they
+// happen to be the first 32 bytes of a private key) so this function is for
+// interoperating with systems that may store just a seed instead of a full
+// private key.
+OPENSSL_EXPORT void ED25519_keypair_from_seed(uint8_t out_public_key[32],
+ uint8_t out_private_key[64],
+ const uint8_t seed[32]);
+
+
+// SPAKE2.
+//
+// SPAKE2 is a password-authenticated key-exchange. It allows two parties,
+// who share a low-entropy secret (i.e. password), to agree on a shared key.
+// An attacker can only make one guess of the password per execution of the
+// protocol.
+//
+// See https://tools.ietf.org/html/draft-irtf-cfrg-spake2-02.
+
+// spake2_role_t enumerates the different “roles” in SPAKE2. The protocol
+// requires that the symmetry of the two parties be broken so one participant
+// must be “Alice” and the other be “Bob”.
+enum spake2_role_t {
+ spake2_role_alice,
+ spake2_role_bob,
+};
+
+// SPAKE2_CTX_new creates a new |SPAKE2_CTX| (which can only be used for a
+// single execution of the protocol). SPAKE2 requires the symmetry of the two
+// parties to be broken which is indicated via |my_role| – each party must pass
+// a different value for this argument.
+//
+// The |my_name| and |their_name| arguments allow optional, opaque names to be
+// bound into the protocol. For example MAC addresses, hostnames, usernames
+// etc. These values are not exposed and can avoid context-confusion attacks
+// when a password is shared between several devices.
+OPENSSL_EXPORT SPAKE2_CTX *SPAKE2_CTX_new(
+ enum spake2_role_t my_role,
+ const uint8_t *my_name, size_t my_name_len,
+ const uint8_t *their_name, size_t their_name_len);
+
+// SPAKE2_CTX_free frees |ctx| and all the resources that it has allocated.
+OPENSSL_EXPORT void SPAKE2_CTX_free(SPAKE2_CTX *ctx);
+
+// SPAKE2_MAX_MSG_SIZE is the maximum size of a SPAKE2 message.
+#define SPAKE2_MAX_MSG_SIZE 32
+
+// SPAKE2_generate_msg generates a SPAKE2 message given |password|, writes
+// it to |out| and sets |*out_len| to the number of bytes written.
+//
+// At most |max_out_len| bytes are written to |out| and, in order to ensure
+// success, |max_out_len| should be at least |SPAKE2_MAX_MSG_SIZE| bytes.
+//
+// This function can only be called once for a given |SPAKE2_CTX|.
+//
+// It returns one on success and zero on error.
+OPENSSL_EXPORT int SPAKE2_generate_msg(SPAKE2_CTX *ctx, uint8_t *out,
+ size_t *out_len, size_t max_out_len,
+ const uint8_t *password,
+ size_t password_len);
+
+// SPAKE2_MAX_KEY_SIZE is the maximum amount of key material that SPAKE2 will
+// produce.
+#define SPAKE2_MAX_KEY_SIZE 64
+
+// SPAKE2_process_msg completes the SPAKE2 exchange given the peer's message in
+// |their_msg|, writes at most |max_out_key_len| bytes to |out_key| and sets
+// |*out_key_len| to the number of bytes written.
+//
+// The resulting keying material is suitable for:
+// a) Using directly in a key-confirmation step: i.e. each side could
+// transmit a hash of their role, a channel-binding value and the key
+// material to prove to the other side that they know the shared key.
+// b) Using as input keying material to HKDF to generate a variety of subkeys
+// for encryption etc.
+//
+// If |max_out_key_key| is smaller than the amount of key material generated
+// then the key is silently truncated. If you want to ensure that no truncation
+// occurs then |max_out_key| should be at least |SPAKE2_MAX_KEY_SIZE|.
+//
+// You must call |SPAKE2_generate_msg| on a given |SPAKE2_CTX| before calling
+// this function. On successful return, |ctx| is complete and calling
+// |SPAKE2_CTX_free| is the only acceptable operation on it.
+//
+// Returns one on success or zero on error.
+OPENSSL_EXPORT int SPAKE2_process_msg(SPAKE2_CTX *ctx, uint8_t *out_key,
+ size_t *out_key_len,
+ size_t max_out_key_len,
+ const uint8_t *their_msg,
+ size_t their_msg_len);
+
+
+#if defined(__cplusplus)
+} // extern C
+
+extern "C++" {
+
+namespace bssl {
+
+BORINGSSL_MAKE_DELETER(SPAKE2_CTX, SPAKE2_CTX_free)
+
+} // namespace bssl
+
+} // extern C++
+
+#endif
+
+#endif // OPENSSL_HEADER_CURVE25519_H
git://repos.xcallymotion.com / motion2.git / blobdiff