This series supersedes [0] '[PATCH] crypto: aegis128/neon - optimize tail
block handling', which is included as patch #3 here, but hasn't been
modified substantially.
Patch #1 should probably go to -stable, even though aegis128 does not appear
to be widely used.
Patches #2 and #3 improve the SIMD code paths.
Patch #4 enables fuzz testing for the SIMD code by registering the generic
code as a separate driver if the SIMD code path is enabled.
Cc: Ondrej Mosnacek <[email protected]>
Cc: Eric Biggers <[email protected]>
[0] https://lore.kernel.org/linux-crypto/[email protected]/
Ard Biesheuvel (4):
crypto: aegis128 - wipe plaintext and tag if decryption fails
crypto: aegis128/neon - optimize tail block handling
crypto: aegis128/neon - move final tag check to SIMD domain
crypto: aegis128 - expose SIMD code path as separate driver
crypto/aegis128-core.c | 201 ++++++++++++++------
crypto/aegis128-neon-inner.c | 122 ++++++++++--
crypto/aegis128-neon.c | 21 +-
3 files changed, 263 insertions(+), 81 deletions(-)
--
2.17.1
The AEGIS spec mentions explicitly that the security guarantees hold
only if the resulting plaintext and tag of a failed decryption are
not disclosed. So ensure that we abide by this.
While at it, drop the unused struct aead_request *req parameter from
crypto_aegis128_process_crypt().
Signed-off-by: Ard Biesheuvel <[email protected]>
---
crypto/aegis128-core.c | 32 ++++++++++++++++----
1 file changed, 26 insertions(+), 6 deletions(-)
diff --git a/crypto/aegis128-core.c b/crypto/aegis128-core.c
index 44fb4956f0dd..3a71235892f5 100644
--- a/crypto/aegis128-core.c
+++ b/crypto/aegis128-core.c
@@ -154,6 +154,12 @@ static void crypto_aegis128_ad(struct aegis_state *state,
}
}
+static void crypto_aegis128_wipe_chunk(struct aegis_state *state, u8 *dst,
+ const u8 *src, unsigned int size)
+{
+ memzero_explicit(dst, size);
+}
+
static void crypto_aegis128_encrypt_chunk(struct aegis_state *state, u8 *dst,
const u8 *src, unsigned int size)
{
@@ -324,7 +330,6 @@ static void crypto_aegis128_process_ad(struct aegis_state *state,
static __always_inline
int crypto_aegis128_process_crypt(struct aegis_state *state,
- struct aead_request *req,
struct skcipher_walk *walk,
void (*crypt)(struct aegis_state *state,
u8 *dst, const u8 *src,
@@ -403,14 +408,14 @@ static int crypto_aegis128_encrypt(struct aead_request *req)
if (aegis128_do_simd()) {
crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
crypto_aegis128_process_ad(&state, req->src, req->assoclen);
- crypto_aegis128_process_crypt(&state, req, &walk,
+ crypto_aegis128_process_crypt(&state, &walk,
crypto_aegis128_encrypt_chunk_simd);
crypto_aegis128_final_simd(&state, &tag, req->assoclen,
cryptlen);
} else {
crypto_aegis128_init(&state, &ctx->key, req->iv);
crypto_aegis128_process_ad(&state, req->src, req->assoclen);
- crypto_aegis128_process_crypt(&state, req, &walk,
+ crypto_aegis128_process_crypt(&state, &walk,
crypto_aegis128_encrypt_chunk);
crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen);
}
@@ -438,19 +443,34 @@ static int crypto_aegis128_decrypt(struct aead_request *req)
if (aegis128_do_simd()) {
crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
crypto_aegis128_process_ad(&state, req->src, req->assoclen);
- crypto_aegis128_process_crypt(&state, req, &walk,
+ crypto_aegis128_process_crypt(&state, &walk,
crypto_aegis128_decrypt_chunk_simd);
crypto_aegis128_final_simd(&state, &tag, req->assoclen,
cryptlen);
} else {
crypto_aegis128_init(&state, &ctx->key, req->iv);
crypto_aegis128_process_ad(&state, req->src, req->assoclen);
- crypto_aegis128_process_crypt(&state, req, &walk,
+ crypto_aegis128_process_crypt(&state, &walk,
crypto_aegis128_decrypt_chunk);
crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen);
}
- return crypto_memneq(tag.bytes, zeros, authsize) ? -EBADMSG : 0;
+ if (unlikely(crypto_memneq(tag.bytes, zeros, authsize))) {
+ /*
+ * From Chapter 4. 'Security Analysis' of the AEGIS spec [0]
+ *
+ * "3. If verification fails, the decrypted plaintext and the
+ * wrong authentication tag should not be given as output."
+ *
+ * [0] https://competitions.cr.yp.to/round3/aegisv11.pdf
+ */
+ skcipher_walk_aead_decrypt(&walk, req, false);
+ crypto_aegis128_process_crypt(NULL, &walk,
+ crypto_aegis128_wipe_chunk);
+ memzero_explicit(&tag, sizeof(tag));
+ return -EBADMSG;
+ }
+ return 0;
}
static struct aead_alg crypto_aegis128_alg = {
--
2.17.1
Avoid copying the tail block via a stack buffer if the total size
exceeds a single AEGIS block. In this case, we can use overlapping
loads and stores and NEON permutation instructions instead, which
leads to a modest performance improvement on some cores (< 5%),
and is slightly cleaner. Note that we still need to use a stack
buffer if the entire input is smaller than 16 bytes, given that
we cannot use 16 byte NEON loads and stores safely in this case.
Signed-off-by: Ard Biesheuvel <[email protected]>
---
crypto/aegis128-neon-inner.c | 89 +++++++++++++++++---
1 file changed, 75 insertions(+), 14 deletions(-)
diff --git a/crypto/aegis128-neon-inner.c b/crypto/aegis128-neon-inner.c
index 2a660ac1bc3a..cd1b3ad1d1f3 100644
--- a/crypto/aegis128-neon-inner.c
+++ b/crypto/aegis128-neon-inner.c
@@ -20,7 +20,6 @@
extern int aegis128_have_aes_insn;
void *memcpy(void *dest, const void *src, size_t n);
-void *memset(void *s, int c, size_t n);
struct aegis128_state {
uint8x16_t v[5];
@@ -173,10 +172,46 @@ void crypto_aegis128_update_neon(void *state, const void *msg)
aegis128_save_state_neon(st, state);
}
+#ifdef CONFIG_ARM
+/*
+ * AArch32 does not provide these intrinsics natively because it does not
+ * implement the underlying instructions. AArch32 only provides 64-bit
+ * wide vtbl.8/vtbx.8 instruction, so use those instead.
+ */
+static uint8x16_t vqtbl1q_u8(uint8x16_t a, uint8x16_t b)
+{
+ union {
+ uint8x16_t val;
+ uint8x8x2_t pair;
+ } __a = { a };
+
+ return vcombine_u8(vtbl2_u8(__a.pair, vget_low_u8(b)),
+ vtbl2_u8(__a.pair, vget_high_u8(b)));
+}
+
+static uint8x16_t vqtbx1q_u8(uint8x16_t v, uint8x16_t a, uint8x16_t b)
+{
+ union {
+ uint8x16_t val;
+ uint8x8x2_t pair;
+ } __a = { a };
+
+ return vcombine_u8(vtbx2_u8(vget_low_u8(v), __a.pair, vget_low_u8(b)),
+ vtbx2_u8(vget_high_u8(v), __a.pair, vget_high_u8(b)));
+}
+#endif
+
+static const uint8_t permute[] __aligned(64) = {
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
+};
+
void crypto_aegis128_encrypt_chunk_neon(void *state, void *dst, const void *src,
unsigned int size)
{
struct aegis128_state st = aegis128_load_state_neon(state);
+ const int short_input = size < AEGIS_BLOCK_SIZE;
uint8x16_t msg;
preload_sbox();
@@ -186,7 +221,8 @@ void crypto_aegis128_encrypt_chunk_neon(void *state, void *dst, const void *src,
msg = vld1q_u8(src);
st = aegis128_update_neon(st, msg);
- vst1q_u8(dst, msg ^ s);
+ msg ^= s;
+ vst1q_u8(dst, msg);
size -= AEGIS_BLOCK_SIZE;
src += AEGIS_BLOCK_SIZE;
@@ -195,13 +231,26 @@ void crypto_aegis128_encrypt_chunk_neon(void *state, void *dst, const void *src,
if (size > 0) {
uint8x16_t s = st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];
- uint8_t buf[AEGIS_BLOCK_SIZE] = {};
+ uint8_t buf[AEGIS_BLOCK_SIZE];
+ const void *in = src;
+ void *out = dst;
+ uint8x16_t m;
- memcpy(buf, src, size);
- msg = vld1q_u8(buf);
- st = aegis128_update_neon(st, msg);
- vst1q_u8(buf, msg ^ s);
- memcpy(dst, buf, size);
+ if (__builtin_expect(short_input, 0))
+ in = out = memcpy(buf + AEGIS_BLOCK_SIZE - size, src, size);
+
+ m = vqtbl1q_u8(vld1q_u8(in + size - AEGIS_BLOCK_SIZE),
+ vld1q_u8(permute + 32 - size));
+
+ st = aegis128_update_neon(st, m);
+
+ vst1q_u8(out + size - AEGIS_BLOCK_SIZE,
+ vqtbl1q_u8(m ^ s, vld1q_u8(permute + size)));
+
+ if (__builtin_expect(short_input, 0))
+ memcpy(dst, out, size);
+ else
+ vst1q_u8(out - AEGIS_BLOCK_SIZE, msg);
}
aegis128_save_state_neon(st, state);
@@ -211,6 +260,7 @@ void crypto_aegis128_decrypt_chunk_neon(void *state, void *dst, const void *src,
unsigned int size)
{
struct aegis128_state st = aegis128_load_state_neon(state);
+ const int short_input = size < AEGIS_BLOCK_SIZE;
uint8x16_t msg;
preload_sbox();
@@ -228,14 +278,25 @@ void crypto_aegis128_decrypt_chunk_neon(void *state, void *dst, const void *src,
if (size > 0) {
uint8x16_t s = st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];
uint8_t buf[AEGIS_BLOCK_SIZE];
+ const void *in = src;
+ void *out = dst;
+ uint8x16_t m;
- vst1q_u8(buf, s);
- memcpy(buf, src, size);
- msg = vld1q_u8(buf) ^ s;
- vst1q_u8(buf, msg);
- memcpy(dst, buf, size);
+ if (__builtin_expect(short_input, 0))
+ in = out = memcpy(buf + AEGIS_BLOCK_SIZE - size, src, size);
- st = aegis128_update_neon(st, msg);
+ m = s ^ vqtbx1q_u8(s, vld1q_u8(in + size - AEGIS_BLOCK_SIZE),
+ vld1q_u8(permute + 32 - size));
+
+ st = aegis128_update_neon(st, m);
+
+ vst1q_u8(out + size - AEGIS_BLOCK_SIZE,
+ vqtbl1q_u8(m, vld1q_u8(permute + size)));
+
+ if (__builtin_expect(short_input, 0))
+ memcpy(dst, out, size);
+ else
+ vst1q_u8(out - AEGIS_BLOCK_SIZE, msg);
}
aegis128_save_state_neon(st, state);
--
2.17.1
Instead of calculating the tag and returning it to the caller on
decryption, use a SIMD compare and min across vector to perform
the comparison. This is slightly more efficient, and removes the
need on the caller's part to wipe the tag from memory if the
decryption failed.
While at it, switch to unsigned int when passing cryptlen and
assoclen - we don't support input sizes where the difference
matters anyway.
Signed-off-by: Ard Biesheuvel <[email protected]>
---
crypto/aegis128-core.c | 21 +++++++++----
crypto/aegis128-neon-inner.c | 33 ++++++++++++++++----
crypto/aegis128-neon.c | 21 +++++++++----
3 files changed, 57 insertions(+), 18 deletions(-)
diff --git a/crypto/aegis128-core.c b/crypto/aegis128-core.c
index 3a71235892f5..859c7b905618 100644
--- a/crypto/aegis128-core.c
+++ b/crypto/aegis128-core.c
@@ -67,9 +67,11 @@ void crypto_aegis128_encrypt_chunk_simd(struct aegis_state *state, u8 *dst,
const u8 *src, unsigned int size);
void crypto_aegis128_decrypt_chunk_simd(struct aegis_state *state, u8 *dst,
const u8 *src, unsigned int size);
-void crypto_aegis128_final_simd(struct aegis_state *state,
- union aegis_block *tag_xor,
- u64 assoclen, u64 cryptlen);
+int crypto_aegis128_final_simd(struct aegis_state *state,
+ union aegis_block *tag_xor,
+ unsigned int assoclen,
+ unsigned int cryptlen,
+ unsigned int authsize);
static void crypto_aegis128_update(struct aegis_state *state)
{
@@ -411,7 +413,7 @@ static int crypto_aegis128_encrypt(struct aead_request *req)
crypto_aegis128_process_crypt(&state, &walk,
crypto_aegis128_encrypt_chunk_simd);
crypto_aegis128_final_simd(&state, &tag, req->assoclen,
- cryptlen);
+ cryptlen, 0);
} else {
crypto_aegis128_init(&state, &ctx->key, req->iv);
crypto_aegis128_process_ad(&state, req->src, req->assoclen);
@@ -445,8 +447,15 @@ static int crypto_aegis128_decrypt(struct aead_request *req)
crypto_aegis128_process_ad(&state, req->src, req->assoclen);
crypto_aegis128_process_crypt(&state, &walk,
crypto_aegis128_decrypt_chunk_simd);
- crypto_aegis128_final_simd(&state, &tag, req->assoclen,
- cryptlen);
+ if (unlikely(crypto_aegis128_final_simd(&state, &tag,
+ req->assoclen,
+ cryptlen, authsize))) {
+ skcipher_walk_aead_decrypt(&walk, req, false);
+ crypto_aegis128_process_crypt(NULL, &walk,
+ crypto_aegis128_wipe_chunk);
+ return -EBADMSG;
+ }
+ return 0;
} else {
crypto_aegis128_init(&state, &ctx->key, req->iv);
crypto_aegis128_process_ad(&state, req->src, req->assoclen);
diff --git a/crypto/aegis128-neon-inner.c b/crypto/aegis128-neon-inner.c
index cd1b3ad1d1f3..7de485907d81 100644
--- a/crypto/aegis128-neon-inner.c
+++ b/crypto/aegis128-neon-inner.c
@@ -199,6 +199,17 @@ static uint8x16_t vqtbx1q_u8(uint8x16_t v, uint8x16_t a, uint8x16_t b)
return vcombine_u8(vtbx2_u8(vget_low_u8(v), __a.pair, vget_low_u8(b)),
vtbx2_u8(vget_high_u8(v), __a.pair, vget_high_u8(b)));
}
+
+static int8_t vminvq_s8(int8x16_t v)
+{
+ int8x8_t s = vpmin_s8(vget_low_s8(v), vget_high_s8(v));
+
+ s = vpmin_s8(s, s);
+ s = vpmin_s8(s, s);
+ s = vpmin_s8(s, s);
+
+ return vget_lane_s8(s, 0);
+}
#endif
static const uint8_t permute[] __aligned(64) = {
@@ -302,8 +313,10 @@ void crypto_aegis128_decrypt_chunk_neon(void *state, void *dst, const void *src,
aegis128_save_state_neon(st, state);
}
-void crypto_aegis128_final_neon(void *state, void *tag_xor, uint64_t assoclen,
- uint64_t cryptlen)
+int crypto_aegis128_final_neon(void *state, void *tag_xor,
+ unsigned int assoclen,
+ unsigned int cryptlen,
+ unsigned int authsize)
{
struct aegis128_state st = aegis128_load_state_neon(state);
uint8x16_t v;
@@ -311,13 +324,21 @@ void crypto_aegis128_final_neon(void *state, void *tag_xor, uint64_t assoclen,
preload_sbox();
- v = st.v[3] ^ (uint8x16_t)vcombine_u64(vmov_n_u64(8 * assoclen),
- vmov_n_u64(8 * cryptlen));
+ v = st.v[3] ^ (uint8x16_t)vcombine_u64(vmov_n_u64(8ULL * assoclen),
+ vmov_n_u64(8ULL * cryptlen));
for (i = 0; i < 7; i++)
st = aegis128_update_neon(st, v);
- v = vld1q_u8(tag_xor);
- v ^= st.v[0] ^ st.v[1] ^ st.v[2] ^ st.v[3] ^ st.v[4];
+ v = st.v[0] ^ st.v[1] ^ st.v[2] ^ st.v[3] ^ st.v[4];
+
+ if (authsize > 0) {
+ v = vqtbl1q_u8(~vceqq_u8(v, vld1q_u8(tag_xor)),
+ vld1q_u8(permute + authsize));
+
+ return vminvq_s8((int8x16_t)v);
+ }
+
vst1q_u8(tag_xor, v);
+ return 0;
}
diff --git a/crypto/aegis128-neon.c b/crypto/aegis128-neon.c
index 8271b1fa0fbc..94d591a002a4 100644
--- a/crypto/aegis128-neon.c
+++ b/crypto/aegis128-neon.c
@@ -14,8 +14,10 @@ void crypto_aegis128_encrypt_chunk_neon(void *state, void *dst, const void *src,
unsigned int size);
void crypto_aegis128_decrypt_chunk_neon(void *state, void *dst, const void *src,
unsigned int size);
-void crypto_aegis128_final_neon(void *state, void *tag_xor, uint64_t assoclen,
- uint64_t cryptlen);
+int crypto_aegis128_final_neon(void *state, void *tag_xor,
+ unsigned int assoclen,
+ unsigned int cryptlen,
+ unsigned int authsize);
int aegis128_have_aes_insn __ro_after_init;
@@ -60,11 +62,18 @@ void crypto_aegis128_decrypt_chunk_simd(union aegis_block *state, u8 *dst,
kernel_neon_end();
}
-void crypto_aegis128_final_simd(union aegis_block *state,
- union aegis_block *tag_xor,
- u64 assoclen, u64 cryptlen)
+int crypto_aegis128_final_simd(union aegis_block *state,
+ union aegis_block *tag_xor,
+ unsigned int assoclen,
+ unsigned int cryptlen,
+ unsigned int authsize)
{
+ int ret;
+
kernel_neon_begin();
- crypto_aegis128_final_neon(state, tag_xor, assoclen, cryptlen);
+ ret = crypto_aegis128_final_neon(state, tag_xor, assoclen, cryptlen,
+ authsize);
kernel_neon_end();
+
+ return ret;
}
--
2.17.1
Wiring the SIMD code into the generic driver has the unfortunate side
effect that the tcrypt testing code cannot distinguish them, and will
therefore not use the latter to fuzz test the former, as it does for
other algorithms.
So let's refactor the code a bit so we can register two implementations:
aegis128-generic and aegis128-simd.
Signed-off-by: Ard Biesheuvel <[email protected]>
---
crypto/aegis128-core.c | 176 +++++++++++++-------
1 file changed, 119 insertions(+), 57 deletions(-)
diff --git a/crypto/aegis128-core.c b/crypto/aegis128-core.c
index 859c7b905618..19f38e8c1627 100644
--- a/crypto/aegis128-core.c
+++ b/crypto/aegis128-core.c
@@ -396,7 +396,7 @@ static int crypto_aegis128_setauthsize(struct crypto_aead *tfm,
return 0;
}
-static int crypto_aegis128_encrypt(struct aead_request *req)
+static int crypto_aegis128_encrypt_generic(struct aead_request *req)
{
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
union aegis_block tag = {};
@@ -407,27 +407,18 @@ static int crypto_aegis128_encrypt(struct aead_request *req)
struct aegis_state state;
skcipher_walk_aead_encrypt(&walk, req, false);
- if (aegis128_do_simd()) {
- crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
- crypto_aegis128_process_ad(&state, req->src, req->assoclen);
- crypto_aegis128_process_crypt(&state, &walk,
- crypto_aegis128_encrypt_chunk_simd);
- crypto_aegis128_final_simd(&state, &tag, req->assoclen,
- cryptlen, 0);
- } else {
- crypto_aegis128_init(&state, &ctx->key, req->iv);
- crypto_aegis128_process_ad(&state, req->src, req->assoclen);
- crypto_aegis128_process_crypt(&state, &walk,
- crypto_aegis128_encrypt_chunk);
- crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen);
- }
+ crypto_aegis128_init(&state, &ctx->key, req->iv);
+ crypto_aegis128_process_ad(&state, req->src, req->assoclen);
+ crypto_aegis128_process_crypt(&state, &walk,
+ crypto_aegis128_encrypt_chunk);
+ crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen);
scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen,
authsize, 1);
return 0;
}
-static int crypto_aegis128_decrypt(struct aead_request *req)
+static int crypto_aegis128_decrypt_generic(struct aead_request *req)
{
static const u8 zeros[AEGIS128_MAX_AUTH_SIZE] = {};
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
@@ -442,27 +433,11 @@ static int crypto_aegis128_decrypt(struct aead_request *req)
authsize, 0);
skcipher_walk_aead_decrypt(&walk, req, false);
- if (aegis128_do_simd()) {
- crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
- crypto_aegis128_process_ad(&state, req->src, req->assoclen);
- crypto_aegis128_process_crypt(&state, &walk,
- crypto_aegis128_decrypt_chunk_simd);
- if (unlikely(crypto_aegis128_final_simd(&state, &tag,
- req->assoclen,
- cryptlen, authsize))) {
- skcipher_walk_aead_decrypt(&walk, req, false);
- crypto_aegis128_process_crypt(NULL, &walk,
- crypto_aegis128_wipe_chunk);
- return -EBADMSG;
- }
- return 0;
- } else {
- crypto_aegis128_init(&state, &ctx->key, req->iv);
- crypto_aegis128_process_ad(&state, req->src, req->assoclen);
- crypto_aegis128_process_crypt(&state, &walk,
- crypto_aegis128_decrypt_chunk);
- crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen);
- }
+ crypto_aegis128_init(&state, &ctx->key, req->iv);
+ crypto_aegis128_process_ad(&state, req->src, req->assoclen);
+ crypto_aegis128_process_crypt(&state, &walk,
+ crypto_aegis128_decrypt_chunk);
+ crypto_aegis128_final(&state, &tag, req->assoclen, cryptlen);
if (unlikely(crypto_memneq(tag.bytes, zeros, authsize))) {
/*
@@ -482,42 +457,128 @@ static int crypto_aegis128_decrypt(struct aead_request *req)
return 0;
}
-static struct aead_alg crypto_aegis128_alg = {
- .setkey = crypto_aegis128_setkey,
- .setauthsize = crypto_aegis128_setauthsize,
- .encrypt = crypto_aegis128_encrypt,
- .decrypt = crypto_aegis128_decrypt,
+static int crypto_aegis128_encrypt_simd(struct aead_request *req)
+{
+ struct crypto_aead *tfm = crypto_aead_reqtfm(req);
+ union aegis_block tag = {};
+ unsigned int authsize = crypto_aead_authsize(tfm);
+ struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
+ unsigned int cryptlen = req->cryptlen;
+ struct skcipher_walk walk;
+ struct aegis_state state;
- .ivsize = AEGIS128_NONCE_SIZE,
- .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
- .chunksize = AEGIS_BLOCK_SIZE,
+ if (!aegis128_do_simd())
+ return crypto_aegis128_encrypt_generic(req);
- .base = {
- .cra_blocksize = 1,
- .cra_ctxsize = sizeof(struct aegis_ctx),
- .cra_alignmask = 0,
+ skcipher_walk_aead_encrypt(&walk, req, false);
+ crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
+ crypto_aegis128_process_ad(&state, req->src, req->assoclen);
+ crypto_aegis128_process_crypt(&state, &walk,
+ crypto_aegis128_encrypt_chunk_simd);
+ crypto_aegis128_final_simd(&state, &tag, req->assoclen, cryptlen, 0);
- .cra_priority = 100,
+ scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen,
+ authsize, 1);
+ return 0;
+}
- .cra_name = "aegis128",
- .cra_driver_name = "aegis128-generic",
+static int crypto_aegis128_decrypt_simd(struct aead_request *req)
+{
+ struct crypto_aead *tfm = crypto_aead_reqtfm(req);
+ union aegis_block tag;
+ unsigned int authsize = crypto_aead_authsize(tfm);
+ unsigned int cryptlen = req->cryptlen - authsize;
+ struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
+ struct skcipher_walk walk;
+ struct aegis_state state;
+
+ if (!aegis128_do_simd())
+ return crypto_aegis128_decrypt_generic(req);
+
+ scatterwalk_map_and_copy(tag.bytes, req->src, req->assoclen + cryptlen,
+ authsize, 0);
+
+ skcipher_walk_aead_decrypt(&walk, req, false);
+ crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
+ crypto_aegis128_process_ad(&state, req->src, req->assoclen);
+ crypto_aegis128_process_crypt(&state, &walk,
+ crypto_aegis128_decrypt_chunk_simd);
- .cra_module = THIS_MODULE,
+ if (unlikely(crypto_aegis128_final_simd(&state, &tag, req->assoclen,
+ cryptlen, authsize))) {
+ skcipher_walk_aead_decrypt(&walk, req, false);
+ crypto_aegis128_process_crypt(NULL, &walk,
+ crypto_aegis128_wipe_chunk);
+ return -EBADMSG;
}
+ return 0;
+}
+
+static struct aead_alg crypto_aegis128_alg_generic = {
+ .setkey = crypto_aegis128_setkey,
+ .setauthsize = crypto_aegis128_setauthsize,
+ .encrypt = crypto_aegis128_encrypt_generic,
+ .decrypt = crypto_aegis128_decrypt_generic,
+
+ .ivsize = AEGIS128_NONCE_SIZE,
+ .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
+ .chunksize = AEGIS_BLOCK_SIZE,
+
+ .base.cra_blocksize = 1,
+ .base.cra_ctxsize = sizeof(struct aegis_ctx),
+ .base.cra_alignmask = 0,
+ .base.cra_priority = 100,
+ .base.cra_name = "aegis128",
+ .base.cra_driver_name = "aegis128-generic",
+};
+
+static struct aead_alg crypto_aegis128_alg_simd = {
+ .base.cra_module = THIS_MODULE,
+ .setkey = crypto_aegis128_setkey,
+ .setauthsize = crypto_aegis128_setauthsize,
+ .encrypt = crypto_aegis128_encrypt_simd,
+ .decrypt = crypto_aegis128_decrypt_simd,
+
+ .ivsize = AEGIS128_NONCE_SIZE,
+ .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
+ .chunksize = AEGIS_BLOCK_SIZE,
+
+ .base.cra_blocksize = 1,
+ .base.cra_ctxsize = sizeof(struct aegis_ctx),
+ .base.cra_alignmask = 0,
+ .base.cra_priority = 200,
+ .base.cra_name = "aegis128",
+ .base.cra_driver_name = "aegis128-simd",
+ .base.cra_module = THIS_MODULE,
};
static int __init crypto_aegis128_module_init(void)
{
+ int ret;
+
+ ret = crypto_register_aead(&crypto_aegis128_alg_generic);
+ if (ret)
+ return ret;
+
if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) &&
- crypto_aegis128_have_simd())
+ crypto_aegis128_have_simd()) {
+ ret = crypto_register_aead(&crypto_aegis128_alg_simd);
+ if (ret) {
+ crypto_unregister_aead(&crypto_aegis128_alg_generic);
+ return ret;
+ }
static_branch_enable(&have_simd);
-
- return crypto_register_aead(&crypto_aegis128_alg);
+ }
+ return 0;
}
static void __exit crypto_aegis128_module_exit(void)
{
- crypto_unregister_aead(&crypto_aegis128_alg);
+ if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) &&
+ crypto_aegis128_have_simd())
+ crypto_unregister_aead(&crypto_aegis128_alg_simd);
+
+ crypto_unregister_aead(&crypto_aegis128_alg_generic);
}
subsys_initcall(crypto_aegis128_module_init);
@@ -528,3 +589,4 @@ MODULE_AUTHOR("Ondrej Mosnacek <[email protected]>");
MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm");
MODULE_ALIAS_CRYPTO("aegis128");
MODULE_ALIAS_CRYPTO("aegis128-generic");
+MODULE_ALIAS_CRYPTO("aegis128-simd");
--
2.17.1
ut 10. 11. 2020 o 20:04 Ard Biesheuvel <[email protected]> napísal(a):
> The AEGIS spec mentions explicitly that the security guarantees hold
> only if the resulting plaintext and tag of a failed decryption are
> not disclosed. So ensure that we abide by this.
>
> While at it, drop the unused struct aead_request *req parameter from
> crypto_aegis128_process_crypt().
>
> Signed-off-by: Ard Biesheuvel <[email protected]>
> ---
> crypto/aegis128-core.c | 32 ++++++++++++++++----
> 1 file changed, 26 insertions(+), 6 deletions(-)
Reviewed-by: Ondrej Mosnacek <[email protected]>
ut 10. 11. 2020 o 20:04 Ard Biesheuvel <[email protected]> napísal(a):
> Wiring the SIMD code into the generic driver has the unfortunate side
> effect that the tcrypt testing code cannot distinguish them, and will
> therefore not use the latter to fuzz test the former, as it does for
> other algorithms.
Looking back at cf3d41adcc35 ("crypto: aegis128 - add support for SIMD
acceleration"), I see that that there are aegis128_do_simd()
conditionals also in the generic block update functions, so the
"generic" variant is really only "half" generic. But maybe that
doesn't really matter for the fuzzing, since the code paths are
significantly different anyway...
>
> So let's refactor the code a bit so we can register two implementations:
> aegis128-generic and aegis128-simd.
>
> Signed-off-by: Ard Biesheuvel <[email protected]>
> ---
> crypto/aegis128-core.c | 176 +++++++++++++-------
> 1 file changed, 119 insertions(+), 57 deletions(-)
>
> diff --git a/crypto/aegis128-core.c b/crypto/aegis128-core.c
> index 859c7b905618..19f38e8c1627 100644
> --- a/crypto/aegis128-core.c
> +++ b/crypto/aegis128-core.c
[...]
> @@ -482,42 +457,128 @@ static int crypto_aegis128_decrypt(struct aead_request *req)
> return 0;
> }
>
> -static struct aead_alg crypto_aegis128_alg = {
> - .setkey = crypto_aegis128_setkey,
> - .setauthsize = crypto_aegis128_setauthsize,
> - .encrypt = crypto_aegis128_encrypt,
> - .decrypt = crypto_aegis128_decrypt,
> +static int crypto_aegis128_encrypt_simd(struct aead_request *req)
> +{
> + struct crypto_aead *tfm = crypto_aead_reqtfm(req);
> + union aegis_block tag = {};
> + unsigned int authsize = crypto_aead_authsize(tfm);
> + struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
> + unsigned int cryptlen = req->cryptlen;
> + struct skcipher_walk walk;
> + struct aegis_state state;
>
> - .ivsize = AEGIS128_NONCE_SIZE,
> - .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
> - .chunksize = AEGIS_BLOCK_SIZE,
> + if (!aegis128_do_simd())
> + return crypto_aegis128_encrypt_generic(req);
>
> - .base = {
> - .cra_blocksize = 1,
> - .cra_ctxsize = sizeof(struct aegis_ctx),
> - .cra_alignmask = 0,
> + skcipher_walk_aead_encrypt(&walk, req, false);
> + crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
> + crypto_aegis128_process_ad(&state, req->src, req->assoclen);
> + crypto_aegis128_process_crypt(&state, &walk,
> + crypto_aegis128_encrypt_chunk_simd);
> + crypto_aegis128_final_simd(&state, &tag, req->assoclen, cryptlen, 0);
>
> - .cra_priority = 100,
> + scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen,
> + authsize, 1);
> + return 0;
> +}
>
> - .cra_name = "aegis128",
> - .cra_driver_name = "aegis128-generic",
> +static int crypto_aegis128_decrypt_simd(struct aead_request *req)
> +{
> + struct crypto_aead *tfm = crypto_aead_reqtfm(req);
> + union aegis_block tag;
> + unsigned int authsize = crypto_aead_authsize(tfm);
> + unsigned int cryptlen = req->cryptlen - authsize;
> + struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
> + struct skcipher_walk walk;
> + struct aegis_state state;
> +
> + if (!aegis128_do_simd())
> + return crypto_aegis128_decrypt_generic(req);
> +
> + scatterwalk_map_and_copy(tag.bytes, req->src, req->assoclen + cryptlen,
> + authsize, 0);
> +
> + skcipher_walk_aead_decrypt(&walk, req, false);
> + crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
> + crypto_aegis128_process_ad(&state, req->src, req->assoclen);
> + crypto_aegis128_process_crypt(&state, &walk,
> + crypto_aegis128_decrypt_chunk_simd);
>
> - .cra_module = THIS_MODULE,
> + if (unlikely(crypto_aegis128_final_simd(&state, &tag, req->assoclen,
> + cryptlen, authsize))) {
> + skcipher_walk_aead_decrypt(&walk, req, false);
> + crypto_aegis128_process_crypt(NULL, &walk,
> + crypto_aegis128_wipe_chunk);
> + return -EBADMSG;
> }
> + return 0;
> +}
> +
> +static struct aead_alg crypto_aegis128_alg_generic = {
> + .setkey = crypto_aegis128_setkey,
> + .setauthsize = crypto_aegis128_setauthsize,
> + .encrypt = crypto_aegis128_encrypt_generic,
> + .decrypt = crypto_aegis128_decrypt_generic,
> +
> + .ivsize = AEGIS128_NONCE_SIZE,
> + .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
> + .chunksize = AEGIS_BLOCK_SIZE,
> +
> + .base.cra_blocksize = 1,
> + .base.cra_ctxsize = sizeof(struct aegis_ctx),
> + .base.cra_alignmask = 0,
> + .base.cra_priority = 100,
> + .base.cra_name = "aegis128",
> + .base.cra_driver_name = "aegis128-generic",
> +};
> +
> +static struct aead_alg crypto_aegis128_alg_simd = {
> + .base.cra_module = THIS_MODULE,
This line is listed twice for "crypto_aegis128_alg_simd", but it's
missing for "crypto_aegis128_alg_generic" - I think you meant to put
this one three lines higher.
> + .setkey = crypto_aegis128_setkey,
> + .setauthsize = crypto_aegis128_setauthsize,
> + .encrypt = crypto_aegis128_encrypt_simd,
> + .decrypt = crypto_aegis128_decrypt_simd,
> +
> + .ivsize = AEGIS128_NONCE_SIZE,
> + .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
> + .chunksize = AEGIS_BLOCK_SIZE,
> +
> + .base.cra_blocksize = 1,
> + .base.cra_ctxsize = sizeof(struct aegis_ctx),
> + .base.cra_alignmask = 0,
> + .base.cra_priority = 200,
> + .base.cra_name = "aegis128",
> + .base.cra_driver_name = "aegis128-simd",
> + .base.cra_module = THIS_MODULE,
> };
>
> static int __init crypto_aegis128_module_init(void)
> {
> + int ret;
> +
> + ret = crypto_register_aead(&crypto_aegis128_alg_generic);
> + if (ret)
> + return ret;
> +
> if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) &&
> - crypto_aegis128_have_simd())
> + crypto_aegis128_have_simd()) {
> + ret = crypto_register_aead(&crypto_aegis128_alg_simd);
> + if (ret) {
> + crypto_unregister_aead(&crypto_aegis128_alg_generic);
> + return ret;
> + }
> static_branch_enable(&have_simd);
> -
> - return crypto_register_aead(&crypto_aegis128_alg);
> + }
> + return 0;
> }
>
> static void __exit crypto_aegis128_module_exit(void)
> {
> - crypto_unregister_aead(&crypto_aegis128_alg);
> + if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) &&
> + crypto_aegis128_have_simd())
> + crypto_unregister_aead(&crypto_aegis128_alg_simd);
> +
> + crypto_unregister_aead(&crypto_aegis128_alg_generic);
> }
>
> subsys_initcall(crypto_aegis128_module_init);
> @@ -528,3 +589,4 @@ MODULE_AUTHOR("Ondrej Mosnacek <[email protected]>");
> MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm");
> MODULE_ALIAS_CRYPTO("aegis128");
> MODULE_ALIAS_CRYPTO("aegis128-generic");
> +MODULE_ALIAS_CRYPTO("aegis128-simd");
> --
> 2.17.1
>
On Wed, 11 Nov 2020 at 18:46, Ondrej Mosnáček <[email protected]> wrote:
>
> ut 10. 11. 2020 o 20:04 Ard Biesheuvel <[email protected]> napísal(a):
> > Wiring the SIMD code into the generic driver has the unfortunate side
> > effect that the tcrypt testing code cannot distinguish them, and will
> > therefore not use the latter to fuzz test the former, as it does for
> > other algorithms.
>
> Looking back at cf3d41adcc35 ("crypto: aegis128 - add support for SIMD
> acceleration"), I see that that there are aegis128_do_simd()
> conditionals also in the generic block update functions, so the
> "generic" variant is really only "half" generic. But maybe that
> doesn't really matter for the fuzzing, since the code paths are
> significantly different anyway...
>
Thanks for pointing that out. I think we should be pedantic here, and
ensure that the generic code never takes the SIMD code path.
> >
> > So let's refactor the code a bit so we can register two implementations:
> > aegis128-generic and aegis128-simd.
> >
> > Signed-off-by: Ard Biesheuvel <[email protected]>
> > ---
> > crypto/aegis128-core.c | 176 +++++++++++++-------
> > 1 file changed, 119 insertions(+), 57 deletions(-)
> >
> > diff --git a/crypto/aegis128-core.c b/crypto/aegis128-core.c
> > index 859c7b905618..19f38e8c1627 100644
> > --- a/crypto/aegis128-core.c
> > +++ b/crypto/aegis128-core.c
> [...]
> > @@ -482,42 +457,128 @@ static int crypto_aegis128_decrypt(struct aead_request *req)
> > return 0;
> > }
> >
> > -static struct aead_alg crypto_aegis128_alg = {
> > - .setkey = crypto_aegis128_setkey,
> > - .setauthsize = crypto_aegis128_setauthsize,
> > - .encrypt = crypto_aegis128_encrypt,
> > - .decrypt = crypto_aegis128_decrypt,
> > +static int crypto_aegis128_encrypt_simd(struct aead_request *req)
> > +{
> > + struct crypto_aead *tfm = crypto_aead_reqtfm(req);
> > + union aegis_block tag = {};
> > + unsigned int authsize = crypto_aead_authsize(tfm);
> > + struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
> > + unsigned int cryptlen = req->cryptlen;
> > + struct skcipher_walk walk;
> > + struct aegis_state state;
> >
> > - .ivsize = AEGIS128_NONCE_SIZE,
> > - .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
> > - .chunksize = AEGIS_BLOCK_SIZE,
> > + if (!aegis128_do_simd())
> > + return crypto_aegis128_encrypt_generic(req);
> >
> > - .base = {
> > - .cra_blocksize = 1,
> > - .cra_ctxsize = sizeof(struct aegis_ctx),
> > - .cra_alignmask = 0,
> > + skcipher_walk_aead_encrypt(&walk, req, false);
> > + crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
> > + crypto_aegis128_process_ad(&state, req->src, req->assoclen);
> > + crypto_aegis128_process_crypt(&state, &walk,
> > + crypto_aegis128_encrypt_chunk_simd);
> > + crypto_aegis128_final_simd(&state, &tag, req->assoclen, cryptlen, 0);
> >
> > - .cra_priority = 100,
> > + scatterwalk_map_and_copy(tag.bytes, req->dst, req->assoclen + cryptlen,
> > + authsize, 1);
> > + return 0;
> > +}
> >
> > - .cra_name = "aegis128",
> > - .cra_driver_name = "aegis128-generic",
> > +static int crypto_aegis128_decrypt_simd(struct aead_request *req)
> > +{
> > + struct crypto_aead *tfm = crypto_aead_reqtfm(req);
> > + union aegis_block tag;
> > + unsigned int authsize = crypto_aead_authsize(tfm);
> > + unsigned int cryptlen = req->cryptlen - authsize;
> > + struct aegis_ctx *ctx = crypto_aead_ctx(tfm);
> > + struct skcipher_walk walk;
> > + struct aegis_state state;
> > +
> > + if (!aegis128_do_simd())
> > + return crypto_aegis128_decrypt_generic(req);
> > +
> > + scatterwalk_map_and_copy(tag.bytes, req->src, req->assoclen + cryptlen,
> > + authsize, 0);
> > +
> > + skcipher_walk_aead_decrypt(&walk, req, false);
> > + crypto_aegis128_init_simd(&state, &ctx->key, req->iv);
> > + crypto_aegis128_process_ad(&state, req->src, req->assoclen);
> > + crypto_aegis128_process_crypt(&state, &walk,
> > + crypto_aegis128_decrypt_chunk_simd);
> >
> > - .cra_module = THIS_MODULE,
> > + if (unlikely(crypto_aegis128_final_simd(&state, &tag, req->assoclen,
> > + cryptlen, authsize))) {
> > + skcipher_walk_aead_decrypt(&walk, req, false);
> > + crypto_aegis128_process_crypt(NULL, &walk,
> > + crypto_aegis128_wipe_chunk);
> > + return -EBADMSG;
> > }
> > + return 0;
> > +}
> > +
> > +static struct aead_alg crypto_aegis128_alg_generic = {
> > + .setkey = crypto_aegis128_setkey,
> > + .setauthsize = crypto_aegis128_setauthsize,
> > + .encrypt = crypto_aegis128_encrypt_generic,
> > + .decrypt = crypto_aegis128_decrypt_generic,
> > +
> > + .ivsize = AEGIS128_NONCE_SIZE,
> > + .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
> > + .chunksize = AEGIS_BLOCK_SIZE,
> > +
> > + .base.cra_blocksize = 1,
> > + .base.cra_ctxsize = sizeof(struct aegis_ctx),
> > + .base.cra_alignmask = 0,
> > + .base.cra_priority = 100,
> > + .base.cra_name = "aegis128",
> > + .base.cra_driver_name = "aegis128-generic",
> > +};
> > +
> > +static struct aead_alg crypto_aegis128_alg_simd = {
> > + .base.cra_module = THIS_MODULE,
>
> This line is listed twice for "crypto_aegis128_alg_simd", but it's
> missing for "crypto_aegis128_alg_generic" - I think you meant to put
> this one three lines higher.
>
Oops. Will fix.
> > + .setkey = crypto_aegis128_setkey,
> > + .setauthsize = crypto_aegis128_setauthsize,
> > + .encrypt = crypto_aegis128_encrypt_simd,
> > + .decrypt = crypto_aegis128_decrypt_simd,
> > +
> > + .ivsize = AEGIS128_NONCE_SIZE,
> > + .maxauthsize = AEGIS128_MAX_AUTH_SIZE,
> > + .chunksize = AEGIS_BLOCK_SIZE,
> > +
> > + .base.cra_blocksize = 1,
> > + .base.cra_ctxsize = sizeof(struct aegis_ctx),
> > + .base.cra_alignmask = 0,
> > + .base.cra_priority = 200,
> > + .base.cra_name = "aegis128",
> > + .base.cra_driver_name = "aegis128-simd",
> > + .base.cra_module = THIS_MODULE,
> > };
> >
> > static int __init crypto_aegis128_module_init(void)
> > {
> > + int ret;
> > +
> > + ret = crypto_register_aead(&crypto_aegis128_alg_generic);
> > + if (ret)
> > + return ret;
> > +
> > if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) &&
> > - crypto_aegis128_have_simd())
> > + crypto_aegis128_have_simd()) {
> > + ret = crypto_register_aead(&crypto_aegis128_alg_simd);
> > + if (ret) {
> > + crypto_unregister_aead(&crypto_aegis128_alg_generic);
> > + return ret;
> > + }
> > static_branch_enable(&have_simd);
> > -
> > - return crypto_register_aead(&crypto_aegis128_alg);
> > + }
> > + return 0;
> > }
> >
> > static void __exit crypto_aegis128_module_exit(void)
> > {
> > - crypto_unregister_aead(&crypto_aegis128_alg);
> > + if (IS_ENABLED(CONFIG_CRYPTO_AEGIS128_SIMD) &&
> > + crypto_aegis128_have_simd())
> > + crypto_unregister_aead(&crypto_aegis128_alg_simd);
> > +
> > + crypto_unregister_aead(&crypto_aegis128_alg_generic);
> > }
> >
> > subsys_initcall(crypto_aegis128_module_init);
> > @@ -528,3 +589,4 @@ MODULE_AUTHOR("Ondrej Mosnacek <[email protected]>");
> > MODULE_DESCRIPTION("AEGIS-128 AEAD algorithm");
> > MODULE_ALIAS_CRYPTO("aegis128");
> > MODULE_ALIAS_CRYPTO("aegis128-generic");
> > +MODULE_ALIAS_CRYPTO("aegis128-simd");
> > --
> > 2.17.1
> >