diff options
author | lloyd <[email protected]> | 2015-02-22 16:07:08 +0000 |
---|---|---|
committer | lloyd <[email protected]> | 2015-02-22 16:07:08 +0000 |
commit | a29ea0e7a493b0076cd9c91b2a89d7452b9f90d8 (patch) | |
tree | 85793121afc24bafb72b3a51f0c31d94e6acb2fa /src/lib/mac/poly1305/poly1305.cpp | |
parent | 5ef7108d620a00ce5b2f6997c8b6ffc0708467d6 (diff) |
Amalgamation fixes; inline the poly1305 header and :: namespace OpenSSL funcs
Diffstat (limited to 'src/lib/mac/poly1305/poly1305.cpp')
-rw-r--r-- | src/lib/mac/poly1305/poly1305.cpp | 131 |
1 files changed, 129 insertions, 2 deletions
diff --git a/src/lib/mac/poly1305/poly1305.cpp b/src/lib/mac/poly1305/poly1305.cpp index 8cf42abbb..5241afcd7 100644 --- a/src/lib/mac/poly1305/poly1305.cpp +++ b/src/lib/mac/poly1305/poly1305.cpp @@ -1,5 +1,8 @@ /* -* Poly1305 +* Derived from poly1305-donna-64.h by Andrew Moon <[email protected]> +* in https://github.com/floodyberry/poly1305-donna +* +* (C) 2014 Andrew Moon * (C) 2014 Jack Lloyd * * Botan is released under the Simplified BSD License (see license.txt) @@ -7,12 +10,136 @@ #include <botan/internal/mac_utils.h> #include <botan/poly1305.h> -#include <botan/internal/poly1305_donna.h> +#include <botan/loadstor.h> +#include <botan/mul128.h> +#include <botan/internal/donna128.h> namespace Botan { BOTAN_REGISTER_MAC_NOARGS(Poly1305); +namespace { + +void poly1305_init(secure_vector<u64bit>& X, const byte key[32]) + { + /* r &= 0xffffffc0ffffffc0ffffffc0fffffff */ + const u64bit t0 = load_le<u64bit>(key, 0); + const u64bit t1 = load_le<u64bit>(key, 1); + + X[0] = ( t0 ) & 0xffc0fffffff; + X[1] = ((t0 >> 44) | (t1 << 20)) & 0xfffffc0ffff; + X[2] = ((t1 >> 24) ) & 0x00ffffffc0f; + + /* h = 0 */ + X[3] = 0; + X[4] = 0; + X[5] = 0; + + /* save pad for later */ + X[6] = load_le<u64bit>(key, 2); + X[7] = load_le<u64bit>(key, 3); + } + +void poly1305_blocks(secure_vector<u64bit>& X, const byte *m, size_t blocks, bool is_final = false) + { +#if !defined(BOTAN_TARGET_HAS_NATIVE_UINT128) + typedef donna128 uint128_t; +#endif + + const u64bit hibit = is_final ? 0 : (static_cast<u64bit>(1) << 40); /* 1 << 128 */ + + const u64bit r0 = X[0]; + const u64bit r1 = X[1]; + const u64bit r2 = X[2]; + + u64bit h0 = X[3+0]; + u64bit h1 = X[3+1]; + u64bit h2 = X[3+2]; + + const u64bit s1 = r1 * (5 << 2); + const u64bit s2 = r2 * (5 << 2); + + while(blocks--) + { + /* h += m[i] */ + const u64bit t0 = load_le<u64bit>(m, 0); + const u64bit t1 = load_le<u64bit>(m, 1); + + h0 += (( t0 ) & 0xfffffffffff); + h1 += (((t0 >> 44) | (t1 << 20)) & 0xfffffffffff); + h2 += (((t1 >> 24) ) & 0x3ffffffffff) | hibit; + + /* h *= r */ + uint128_t d0 = uint128_t(h0) * r0 + uint128_t(h1) * s2 + uint128_t(h2) * s1; + uint128_t d1 = uint128_t(h0) * r1 + uint128_t(h1) * r0 + uint128_t(h2) * s2; + uint128_t d2 = uint128_t(h0) * r2 + uint128_t(h1) * r1 + uint128_t(h2) * r0; + + /* (partial) h %= p */ + u64bit c = carry_shift(d0, 44); h0 = d0 & 0xfffffffffff; + d1 += c; c = carry_shift(d1, 44); h1 = d1 & 0xfffffffffff; + d2 += c; c = carry_shift(d2, 42); h2 = d2 & 0x3ffffffffff; + h0 += c * 5; c = carry_shift(h0, 44); h0 = h0 & 0xfffffffffff; + h1 += c; + + m += 16; + } + + X[3+0] = h0; + X[3+1] = h1; + X[3+2] = h2; + } + +void poly1305_finish(secure_vector<u64bit>& X, byte mac[16]) + { + /* fully carry h */ + u64bit h0 = X[3+0]; + u64bit h1 = X[3+1]; + u64bit h2 = X[3+2]; + + u64bit c; + c = (h1 >> 44); h1 &= 0xfffffffffff; + h2 += c; c = (h2 >> 42); h2 &= 0x3ffffffffff; + h0 += c * 5; c = (h0 >> 44); h0 &= 0xfffffffffff; + h1 += c; c = (h1 >> 44); h1 &= 0xfffffffffff; + h2 += c; c = (h2 >> 42); h2 &= 0x3ffffffffff; + h0 += c * 5; c = (h0 >> 44); h0 &= 0xfffffffffff; + h1 += c; + + /* compute h + -p */ + u64bit g0 = h0 + 5; c = (g0 >> 44); g0 &= 0xfffffffffff; + u64bit g1 = h1 + c; c = (g1 >> 44); g1 &= 0xfffffffffff; + u64bit g2 = h2 + c - (static_cast<u64bit>(1) << 42); + + /* select h if h < p, or h + -p if h >= p */ + c = (g2 >> ((sizeof(u64bit) * 8) - 1)) - 1; + g0 &= c; + g1 &= c; + g2 &= c; + c = ~c; + h0 = (h0 & c) | g0; + h1 = (h1 & c) | g1; + h2 = (h2 & c) | g2; + + /* h = (h + pad) */ + const u64bit t0 = X[6]; + const u64bit t1 = X[7]; + + h0 += (( t0 ) & 0xfffffffffff) ; c = (h0 >> 44); h0 &= 0xfffffffffff; + h1 += (((t0 >> 44) | (t1 << 20)) & 0xfffffffffff) + c; c = (h1 >> 44); h1 &= 0xfffffffffff; + h2 += (((t1 >> 24) ) & 0x3ffffffffff) + c; h2 &= 0x3ffffffffff; + + /* mac = h % (2^128) */ + h0 = ((h0 ) | (h1 << 44)); + h1 = ((h1 >> 20) | (h2 << 24)); + + store_le(&mac[0], h0, h1); + + /* zero out the state */ + zero_mem(&X[0], X.size()); + } + +} + void Poly1305::clear() { zap(m_poly); |