From 7305c533516df296124d6b2415482d2febb7328a Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Sun, 16 Sep 2012 05:22:38 +0200 Subject: Fix alignment for NaCl's core2 assembler implementation of AES128-CTR --- src/fastd.c | 5 +++-- src/fastd.h | 3 ++- src/method_aes128_gcm.c | 23 +++++++++-------------- 3 files changed, 14 insertions(+), 17 deletions(-) diff --git a/src/fastd.c b/src/fastd.c index f1df118..f9d8403 100644 --- a/src/fastd.c +++ b/src/fastd.c @@ -269,7 +269,7 @@ static size_t methods_min_encrypt_head_space(fastd_context *ctx) { ret = s; } - return alignto(ret, 8); + return alignto(ret, 16); } static size_t methods_min_decrypt_head_space(fastd_context *ctx) { @@ -285,7 +285,8 @@ static size_t methods_min_decrypt_head_space(fastd_context *ctx) { ret = s; } - return alignto(ret, 8); + /* ugly hack to get alignment right for aes128-gcm, which needs data aligned to 16 and has a 24 byte header */ + return alignto(ret, 16) + 8; } static size_t methods_min_encrypt_tail_space(fastd_context *ctx) { diff --git a/src/fastd.h b/src/fastd.h index d7946ea..023576b 100644 --- a/src/fastd.h +++ b/src/fastd.h @@ -289,7 +289,8 @@ static inline size_t alignto(size_t l, size_t a) { static inline fastd_buffer fastd_buffer_alloc(size_t len, size_t head_space, size_t tail_space) { size_t base_len = head_space+len+tail_space; - uint8_t *ptr = malloc(base_len); + void *ptr; + posix_memalign(&ptr, 16, base_len); return (fastd_buffer){ .base = ptr, .base_len = base_len, .data = ptr+head_space, .len = len }; } diff --git a/src/method_aes128_gcm.c b/src/method_aes128_gcm.c index 05321fd..bbecb69 100644 --- a/src/method_aes128_gcm.c +++ b/src/method_aes128_gcm.c @@ -40,13 +40,13 @@ typedef union _block_t { uint8_t b[BLOCKBYTES]; uint64_t qw[BLOCKQWORDS]; -} block_t; +} __attribute__((aligned(16))) block_t; struct _fastd_method_session_state { struct timespec valid_till; struct timespec refresh_after; - uint8_t d[crypto_stream_aes128ctr_BEFORENMBYTES]; + fastd_buffer d; block_t H[32][16]; uint8_t send_nonce[NONCEBYTES]; @@ -135,12 +135,6 @@ static inline void xor_a(block_t *x, const block_t *a) { xor(x, x, a); } -static inline void xor_blocks(block_t *out, const block_t *in1, const block_t *in2, size_t n_blocks) { - int i; - for (i = 0; i < n_blocks; i++) - xor(&out[i], &in1[i], &in2[i]); -} - static void aes128ctr(fastd_context *ctx, block_t *out, const block_t *in, size_t n_blocks, const block_t *iv, fastd_method_session_state *session) { if (session->algfd_aesctr >= 0) { if (fastd_linux_alg_aesctr(ctx, session->algfd_aesctr, out, in, n_blocks*BLOCKBYTES, iv->b)) @@ -151,10 +145,7 @@ static void aes128ctr(fastd_context *ctx, block_t *out, const block_t *in, size_ session->algfd_aesctr = -1; } - block_t stream[n_blocks]; - crypto_stream_aes128ctr_afternm((uint8_t*)stream, sizeof(stream), iv->b, session->d); - - xor_blocks(out, in, stream, n_blocks); + crypto_stream_aes128ctr_xor_afternm(out->b, in->b, sizeof(block_t)*n_blocks, iv->b, session->d.data); } static fastd_method_session_state* method_session_init(fastd_context *ctx, uint8_t *secret, size_t length, bool initiator) { @@ -171,7 +162,9 @@ static fastd_method_session_state* method_session_init(fastd_context *ctx, uint8 session->refresh_after = ctx->now; session->refresh_after.tv_sec += ctx->conf->key_refresh; - crypto_stream_aes128ctr_beforenm(session->d, secret); + session->d = fastd_buffer_alloc(crypto_stream_aes128ctr_BEFORENMBYTES, 0, 0); + crypto_stream_aes128ctr_beforenm(session->d.data, secret); + session->algfd_aesctr = fastd_linux_alg_aesctr_init(ctx, secret, KEYBYTES); static const block_t zeroblock = {}; @@ -242,6 +235,8 @@ static void method_session_free(fastd_context *ctx, fastd_method_session_state * if(session) { close(session->algfd_ghash); + fastd_buffer_free(session->d); + memset(session, 0, sizeof(fastd_method_session_state)); free(session); } @@ -292,7 +287,7 @@ static bool method_encrypt(fastd_context *ctx, fastd_peer *peer, fastd_method_se memset(in.data, 0, BLOCKBYTES); size_t tail_len = alignto(in.len, BLOCKBYTES)-in.len; - *out = fastd_buffer_alloc(in.len, alignto(NONCEBYTES, 8), BLOCKBYTES+tail_len); + *out = fastd_buffer_alloc(in.len, alignto(NONCEBYTES, 16), BLOCKBYTES+tail_len); if (tail_len) memset(in.data+in.len, 0, tail_len); -- cgit v1.2.3