crypto: Add ed25519 implementation from OpenSSH.

Reviewed-by: Andreas Schneider <asn@cryptomilk.org>

1 files changed, 74 insertions, 0 deletions

diff --git a/include/libssh/sc25519.h b/include/libssh/sc25519.h
new file mode 100644
index 00000000..5a2c1b85
--- /dev/null
+++ b/include/libssh/sc25519.h
@@ -0,0 +1,74 @@
+/* $OpenBSD: sc25519.h,v 1.3 2013/12/09 11:03:45 markus Exp $ */
+
+/*
+ * Public Domain, Authors: Daniel J. Bernstein, Niels Duif, Tanja Lange,
+ * Peter Schwabe, Bo-Yin Yang.
+ * Copied from supercop-20130419/crypto_sign/ed25519/ref/sc25519.h
+ */
+
+#ifndef SC25519_H
+#define SC25519_H
+
+#define sc25519                  crypto_sign_ed25519_ref_sc25519
+#define shortsc25519             crypto_sign_ed25519_ref_shortsc25519
+#define sc25519_from32bytes      crypto_sign_ed25519_ref_sc25519_from32bytes
+#define shortsc25519_from16bytes crypto_sign_ed25519_ref_shortsc25519_from16bytes
+#define sc25519_from64bytes      crypto_sign_ed25519_ref_sc25519_from64bytes
+#define sc25519_from_shortsc     crypto_sign_ed25519_ref_sc25519_from_shortsc
+#define sc25519_to32bytes        crypto_sign_ed25519_ref_sc25519_to32bytes
+#define sc25519_iszero_vartime   crypto_sign_ed25519_ref_sc25519_iszero_vartime
+#define sc25519_isshort_vartime  crypto_sign_ed25519_ref_sc25519_isshort_vartime
+#define sc25519_lt_vartime       crypto_sign_ed25519_ref_sc25519_lt_vartime
+#define sc25519_add              crypto_sign_ed25519_ref_sc25519_add
+#define sc25519_sub_nored        crypto_sign_ed25519_ref_sc25519_sub_nored
+#define sc25519_mul              crypto_sign_ed25519_ref_sc25519_mul
+#define sc25519_mul_shortsc      crypto_sign_ed25519_ref_sc25519_mul_shortsc
+#define sc25519_window3          crypto_sign_ed25519_ref_sc25519_window3
+#define sc25519_window5          crypto_sign_ed25519_ref_sc25519_window5
+#define sc25519_2interleave2     crypto_sign_ed25519_ref_sc25519_2interleave2
+
+typedef struct {
+  uint32_t v[32];
+} sc25519;
+
+typedef struct {
+  uint32_t v[16];
+} shortsc25519;
+
+void sc25519_from32bytes(sc25519 *r, const unsigned char x[32]);
+
+void shortsc25519_from16bytes(shortsc25519 *r, const unsigned char x[16]);
+
+void sc25519_from64bytes(sc25519 *r, const unsigned char x[64]);
+
+void sc25519_from_shortsc(sc25519 *r, const shortsc25519 *x);
+
+void sc25519_to32bytes(unsigned char r[32], const sc25519 *x);
+
+int sc25519_iszero_vartime(const sc25519 *x);
+
+int sc25519_isshort_vartime(const sc25519 *x);
+
+int sc25519_lt_vartime(const sc25519 *x, const sc25519 *y);
+
+void sc25519_add(sc25519 *r, const sc25519 *x, const sc25519 *y);
+
+void sc25519_sub_nored(sc25519 *r, const sc25519 *x, const sc25519 *y);
+
+void sc25519_mul(sc25519 *r, const sc25519 *x, const sc25519 *y);
+
+void sc25519_mul_shortsc(sc25519 *r, const sc25519 *x, const shortsc25519 *y);
+
+/* Convert s into a representation of the form \sum_{i=0}^{84}r[i]2^3
+ * with r[i] in {-4,...,3}
+ */
+void sc25519_window3(signed char r[85], const sc25519 *s);
+
+/* Convert s into a representation of the form \sum_{i=0}^{50}r[i]2^5
+ * with r[i] in {-16,...,15}
+ */
+void sc25519_window5(signed char r[51], const sc25519 *s);
+
+void sc25519_2interleave2(unsigned char r[127], const sc25519 *s1, const sc25519 *s2);
+
+#endif