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-rw-r--r--src/lib/pubkey/newhope/info.txt7
-rw-r--r--src/lib/pubkey/newhope/newhope.cpp159
-rw-r--r--src/lib/pubkey/newhope/newhope.h30
3 files changed, 91 insertions, 105 deletions
diff --git a/src/lib/pubkey/newhope/info.txt b/src/lib/pubkey/newhope/info.txt
index 08b68fc7a..74ceef989 100644
--- a/src/lib/pubkey/newhope/info.txt
+++ b/src/lib/pubkey/newhope/info.txt
@@ -1,5 +1,10 @@
-define NEWHOPE 20160829
+define NEWHOPE 20161018
<requires>
sha3
+shake_cipher
+
+sha2_32
+ctr
+aes
</requires>
diff --git a/src/lib/pubkey/newhope/newhope.cpp b/src/lib/pubkey/newhope/newhope.cpp
index 25168cc58..35645e93c 100644
--- a/src/lib/pubkey/newhope/newhope.cpp
+++ b/src/lib/pubkey/newhope/newhope.cpp
@@ -10,7 +10,8 @@
*/
#include <botan/newhope.h>
-#include <botan/sha3.h>
+#include <botan/hash.h>
+#include <botan/stream_cipher.h>
#include <botan/loadstor.h>
namespace Botan {
@@ -24,8 +25,6 @@ typedef newhope_poly poly;
#define NEWHOPE_POLY_BYTES 1792
#define NEWHOPE_SEED_BYTES 32
-#define SHAKE128_RATE 168
-
namespace {
/* Incomplete-reduction routines; for details on allowed input ranges
@@ -422,115 +421,57 @@ inline void rec(uint8_t *key, const poly *v, const poly *c)
}
}
-/* Based on the public domain implementation in
- * crypto_hash/keccakc512/simple/ from http://bench.cr.yp.to/supercop.html
- * by Ronny Van Keer
- * and the public domain "TweetFips202" implementation
- * from https://twitter.com/tweetfips202
- * by Gilles Van Assche, Daniel J. Bernstein, and Peter Schwabe */
-
-void keccak_absorb(uint64_t *s,
- unsigned int r,
- const uint8_t *m, size_t mlen,
- uint8_t p)
-{
- size_t i;
- uint8_t t[200];
-
- for (i = 0; i < 25; ++i)
- s[i] = 0;
-
- while (mlen >= r)
- {
- for (i = 0; i < r / 8; ++i)
- s[i] ^= load_le<u64bit>(m, i);
-
- SHA_3::permute(s);
- mlen -= r;
- m += r;
- }
-
- for (i = 0; i < r; ++i)
- t[i] = 0;
- for (i = 0; i < mlen; ++i)
- t[i] = m[i];
- t[i] = p;
- t[r - 1] |= 128;
- for (i = 0; i < r / 8; ++i)
- s[i] ^= load_le<u64bit>(t, i);
-}
-
-inline void keccak_squeezeblocks(uint8_t *h, size_t nblocks,
- uint64_t *s, unsigned int r)
-{
- while(nblocks > 0)
- {
- SHA_3::permute(s);
-
- copy_out_le(h, r, s);
-
- h += r;
- nblocks--;
- }
-}
-
-inline void shake128_absorb(uint64_t *s, const uint8_t *input, size_t inputByteLen)
-{
- keccak_absorb(s, SHAKE128_RATE, input, inputByteLen, 0x1F);
-}
-
-inline void shake128_squeezeblocks(uint8_t *output, size_t nblocks, uint64_t *s)
-{
- keccak_squeezeblocks(output, nblocks, s, SHAKE128_RATE);
-}
-
-void gen_a(poly *a, const uint8_t *seed)
-{
- unsigned int pos=0, ctr=0;
- uint16_t val;
- uint64_t state[25];
- unsigned int nblocks=16;
- uint8_t buf[SHAKE128_RATE*16];
+void gen_a(poly *a, const uint8_t *seed, Newhope_Mode mode)
+ {
+ std::vector<uint8_t> buf(168*16);
- shake128_absorb(state, seed, NEWHOPE_SEED_BYTES);
+ std::unique_ptr<StreamCipher> xof;
- shake128_squeezeblocks((uint8_t *) buf, nblocks, state);
+ if(mode == Newhope_Mode::BoringSSL)
+ {
+ xof = StreamCipher::create("CTR(AES-128)");
+ xof->set_key(seed, 16);
+ xof->set_iv(seed + 16, 16);
+ }
+ else
+ {
+ xof = StreamCipher::create("SHAKE-128");
+ xof->set_key(seed, NEWHOPE_SEED_BYTES);
+ }
- while(ctr < PARAM_N)
- {
- val = (buf[pos] | ((uint16_t) buf[pos+1] << 8)) & 0x3fff; // Specialized for q = 12889
- if(val < PARAM_Q)
- a->coeffs[ctr++] = val;
- pos += 2;
- if(pos > SHAKE128_RATE*nblocks-2)
- {
- nblocks=1;
- shake128_squeezeblocks((uint8_t *) buf,nblocks,state);
- pos = 0;
- }
- }
-}
+ zeroise(buf);
+ xof->encrypt(buf);
-void newhope_hash(uint8_t *output, const uint8_t *input, size_t inputByteLen)
- {
- SHA_3_256 sha3;
+ unsigned int pos=0, ctr=0;
- sha3.update(input, inputByteLen);
- sha3.final(output);
-}
+ while(ctr < PARAM_N)
+ {
+ uint16_t val = (buf[pos] | ((uint16_t) buf[pos+1] << 8)) & 0x3fff; // Specialized for q = 12889
+ if(val < PARAM_Q)
+ a->coeffs[ctr++] = val;
+ pos += 2;
+ if(pos >= buf.size())
+ {
+ zeroise(buf);
+ xof->encrypt(buf);
+ pos = 0;
+ }
+ }
+ }
}
// API FUNCTIONS
-void newhope_keygen(uint8_t *send, poly *sk, RandomNumberGenerator& rng)
+void newhope_keygen(uint8_t *send, poly *sk, RandomNumberGenerator& rng,
+ Newhope_Mode mode)
{
poly a, e, r, pk;
uint8_t seed[NEWHOPE_SEED_BYTES];
rng.randomize(seed, NEWHOPE_SEED_BYTES);
- gen_a(&a, seed);
+ gen_a(&a, seed, mode);
poly_getnoise(rng, sk);
poly_ntt(sk);
@@ -545,13 +486,14 @@ void newhope_keygen(uint8_t *send, poly *sk, RandomNumberGenerator& rng)
}
void newhope_sharedb(uint8_t *sharedkey, uint8_t *send, const uint8_t *received,
- RandomNumberGenerator& rng)
+ RandomNumberGenerator& rng,
+ Newhope_Mode mode)
{
poly sp, ep, v, a, pka, c, epp, bp;
uint8_t seed[NEWHOPE_SEED_BYTES];
decode_a(&pka, seed, received);
- gen_a(&a, seed);
+ gen_a(&a, seed, mode);
poly_getnoise(rng, &sp);
poly_ntt(&sp);
@@ -573,11 +515,19 @@ void newhope_sharedb(uint8_t *sharedkey, uint8_t *send, const uint8_t *received,
rec(sharedkey, &v, &c);
- newhope_hash(sharedkey, sharedkey, 32);
+ std::unique_ptr<HashFunction> hash(HashFunction::create(
+ (mode == Newhope_Mode::SHA3) ? "SHA-3(256)" : "SHA-256"));
+
+ if(!hash)
+ throw Exception("NewHope hash function not available");
+
+ hash->update(sharedkey, 32);
+ hash->final(sharedkey);
}
-void newhope_shareda(uint8_t *sharedkey, const poly *sk, const uint8_t *received)
+void newhope_shareda(uint8_t *sharedkey, const poly *sk, const uint8_t *received,
+ Newhope_Mode mode)
{
poly v,bp, c;
@@ -588,7 +538,14 @@ void newhope_shareda(uint8_t *sharedkey, const poly *sk, const uint8_t *received
rec(sharedkey, &v, &c);
- newhope_hash(sharedkey, sharedkey, 32);
+ std::unique_ptr<HashFunction> hash(HashFunction::create(
+ (mode == Newhope_Mode::SHA3) ? "SHA-3(256)" : "SHA-256"));
+
+ if(!hash)
+ throw Exception("NewHope hash function not available");
+
+ hash->update(sharedkey, 32);
+ hash->final(sharedkey);
}
}
diff --git a/src/lib/pubkey/newhope/newhope.h b/src/lib/pubkey/newhope/newhope.h
index 875c6e092..667f1c4cf 100644
--- a/src/lib/pubkey/newhope/newhope.h
+++ b/src/lib/pubkey/newhope/newhope.h
@@ -28,9 +28,33 @@ typedef struct {
uint16_t coeffs[1024];
} newhope_poly;
-void BOTAN_DLL newhope_keygen(uint8_t *send, newhope_poly *sk, RandomNumberGenerator& rng);
-void BOTAN_DLL newhope_sharedb(uint8_t *sharedkey, uint8_t *send, const uint8_t *received, RandomNumberGenerator& rng);
-void BOTAN_DLL newhope_shareda(uint8_t *sharedkey, const newhope_poly *ska, const uint8_t *received);
+/**
+* This chooses the XOF + hash for NewHope
+
+* The official NewHope specification and reference implementation use
+* SHA-3 and SHAKE-128. BoringSSL instead uses SHA-256 and AES-128 in
+* CTR mode.
+*/
+enum class Newhope_Mode {
+ SHA3,
+ BoringSSL
+};
+
+void BOTAN_DLL newhope_keygen(uint8_t *send,
+ newhope_poly *sk,
+ RandomNumberGenerator& rng,
+ Newhope_Mode = Newhope_Mode::SHA3);
+
+void BOTAN_DLL newhope_sharedb(uint8_t *sharedkey,
+ uint8_t *send,
+ const uint8_t *received,
+ RandomNumberGenerator& rng,
+ Newhope_Mode mode = Newhope_Mode::SHA3);
+
+void BOTAN_DLL newhope_shareda(uint8_t *sharedkey,
+ const newhope_poly *ska,
+ const uint8_t *received,
+ Newhope_Mode mode = Newhope_Mode::SHA3);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-24 13:19:54 +0000