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authorlloyd <[email protected]>2015-02-22 16:07:08 +0000
committerlloyd <[email protected]>2015-02-22 16:07:08 +0000
commita29ea0e7a493b0076cd9c91b2a89d7452b9f90d8 (patch)
tree85793121afc24bafb72b3a51f0c31d94e6acb2fa /src/lib/mac/poly1305/poly1305.cpp
parent5ef7108d620a00ce5b2f6997c8b6ffc0708467d6 (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.cpp131
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);