From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date: Fri, 16 Aug 2019 15:21:50 +0300
Subject: crypto: x86/xts - implement support for ciphertext stealing
Patch-mainline: v5.4-rc1
Git-commit: 8ce5fac2dc1bf64e1e6d2371e4ff9a9bfe8fd49f
References: jsc#SLE-15129
Align the x86 code with the generic XTS template, which now supports
ciphertext stealing as described by the IEEE XTS-AES spec P1619.
Tested-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
arch/x86/crypto/aesni-intel_glue.c | 6 +-
arch/x86/crypto/camellia_aesni_avx2_glue.c | 4 -
arch/x86/crypto/camellia_aesni_avx_glue.c | 4 -
arch/x86/crypto/cast6_avx_glue.c | 4 -
arch/x86/crypto/glue_helper.c | 67 +++++++++++++++++++++++++++--
arch/x86/crypto/serpent_avx2_glue.c | 4 -
arch/x86/crypto/serpent_avx_glue.c | 4 -
arch/x86/crypto/twofish_avx_glue.c | 4 -
arch/x86/include/asm/crypto/glue_helper.h | 2
9 files changed, 81 insertions(+), 18 deletions(-)
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -609,7 +609,8 @@ static int xts_encrypt(struct skcipher_r
return glue_xts_req_128bit(&aesni_enc_xts, req,
XTS_TWEAK_CAST(aesni_xts_tweak),
aes_ctx(ctx->raw_tweak_ctx),
- aes_ctx(ctx->raw_crypt_ctx));
+ aes_ctx(ctx->raw_crypt_ctx),
+ false);
}
static int xts_decrypt(struct skcipher_request *req)
@@ -620,7 +621,8 @@ static int xts_decrypt(struct skcipher_r
return glue_xts_req_128bit(&aesni_dec_xts, req,
XTS_TWEAK_CAST(aesni_xts_tweak),
aes_ctx(ctx->raw_tweak_ctx),
- aes_ctx(ctx->raw_crypt_ctx));
+ aes_ctx(ctx->raw_crypt_ctx),
+ true);
}
static int
--- a/arch/x86/crypto/camellia_aesni_avx2_glue.c
+++ b/arch/x86/crypto/camellia_aesni_avx2_glue.c
@@ -182,7 +182,7 @@ static int xts_encrypt(struct skcipher_r
return glue_xts_req_128bit(&camellia_enc_xts, req,
XTS_TWEAK_CAST(camellia_enc_blk),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, false);
}
static int xts_decrypt(struct skcipher_request *req)
@@ -192,7 +192,7 @@ static int xts_decrypt(struct skcipher_r
return glue_xts_req_128bit(&camellia_dec_xts, req,
XTS_TWEAK_CAST(camellia_enc_blk),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, true);
}
static struct skcipher_alg camellia_algs[] = {
--- a/arch/x86/crypto/camellia_aesni_avx_glue.c
+++ b/arch/x86/crypto/camellia_aesni_avx_glue.c
@@ -208,7 +208,7 @@ static int xts_encrypt(struct skcipher_r
return glue_xts_req_128bit(&camellia_enc_xts, req,
XTS_TWEAK_CAST(camellia_enc_blk),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, false);
}
static int xts_decrypt(struct skcipher_request *req)
@@ -218,7 +218,7 @@ static int xts_decrypt(struct skcipher_r
return glue_xts_req_128bit(&camellia_dec_xts, req,
XTS_TWEAK_CAST(camellia_enc_blk),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, true);
}
static struct skcipher_alg camellia_algs[] = {
--- a/arch/x86/crypto/cast6_avx_glue.c
+++ b/arch/x86/crypto/cast6_avx_glue.c
@@ -201,7 +201,7 @@ static int xts_encrypt(struct skcipher_r
return glue_xts_req_128bit(&cast6_enc_xts, req,
XTS_TWEAK_CAST(__cast6_encrypt),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, false);
}
static int xts_decrypt(struct skcipher_request *req)
@@ -211,7 +211,7 @@ static int xts_decrypt(struct skcipher_r
return glue_xts_req_128bit(&cast6_dec_xts, req,
XTS_TWEAK_CAST(__cast6_encrypt),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, true);
}
static struct skcipher_alg cast6_algs[] = {
--- a/arch/x86/crypto/glue_helper.c
+++ b/arch/x86/crypto/glue_helper.c
@@ -14,6 +14,7 @@
#include <crypto/b128ops.h>
#include <crypto/gf128mul.h>
#include <crypto/internal/skcipher.h>
+#include <crypto/scatterwalk.h>
#include <crypto/xts.h>
#include <asm/crypto/glue_helper.h>
@@ -259,17 +260,36 @@ done:
int glue_xts_req_128bit(const struct common_glue_ctx *gctx,
struct skcipher_request *req,
common_glue_func_t tweak_fn, void *tweak_ctx,
- void *crypt_ctx)
+ void *crypt_ctx, bool decrypt)
{
+ const bool cts = (req->cryptlen % XTS_BLOCK_SIZE);
const unsigned int bsize = 128 / 8;
+ struct skcipher_request subreq;
struct skcipher_walk walk;
bool fpu_enabled = false;
- unsigned int nbytes;
+ unsigned int nbytes, tail;
int err;
+ if (req->cryptlen < XTS_BLOCK_SIZE)
+ return -EINVAL;
+
+ if (unlikely(cts)) {
+ struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+
+ tail = req->cryptlen % XTS_BLOCK_SIZE + XTS_BLOCK_SIZE;
+
+ skcipher_request_set_tfm(&subreq, tfm);
+ skcipher_request_set_callback(&subreq,
+ crypto_skcipher_get_flags(tfm),
+ NULL, NULL);
+ skcipher_request_set_crypt(&subreq, req->src, req->dst,
+ req->cryptlen - tail, req->iv);
+ req = &subreq;
+ }
+
err = skcipher_walk_virt(&walk, req, false);
nbytes = walk.nbytes;
- if (!nbytes)
+ if (err)
return err;
/* set minimum length to bsize, for tweak_fn */
@@ -287,6 +307,47 @@ int glue_xts_req_128bit(const struct com
nbytes = walk.nbytes;
}
+ if (unlikely(cts)) {
+ u8 *next_tweak, *final_tweak = req->iv;
+ struct scatterlist *src, *dst;
+ struct scatterlist s[2], d[2];
+ le128 b[2];
+
+ dst = src = scatterwalk_ffwd(s, req->src, req->cryptlen);
+ if (req->dst != req->src)
+ dst = scatterwalk_ffwd(d, req->dst, req->cryptlen);
+
+ if (decrypt) {
+ next_tweak = memcpy(b, req->iv, XTS_BLOCK_SIZE);
+ gf128mul_x_ble(b, b);
+ } else {
+ next_tweak = req->iv;
+ }
+
+ skcipher_request_set_crypt(&subreq, src, dst, XTS_BLOCK_SIZE,
+ next_tweak);
+
+ err = skcipher_walk_virt(&walk, req, false) ?:
+ skcipher_walk_done(&walk,
+ __glue_xts_req_128bit(gctx, crypt_ctx, &walk));
+ if (err)
+ goto out;
+
+ scatterwalk_map_and_copy(b, dst, 0, XTS_BLOCK_SIZE, 0);
+ memcpy(b + 1, b, tail - XTS_BLOCK_SIZE);
+ scatterwalk_map_and_copy(b, src, XTS_BLOCK_SIZE,
+ tail - XTS_BLOCK_SIZE, 0);
+ scatterwalk_map_and_copy(b, dst, 0, tail, 1);
+
+ skcipher_request_set_crypt(&subreq, dst, dst, XTS_BLOCK_SIZE,
+ final_tweak);
+
+ err = skcipher_walk_virt(&walk, req, false) ?:
+ skcipher_walk_done(&walk,
+ __glue_xts_req_128bit(gctx, crypt_ctx, &walk));
+ }
+
+out:
glue_fpu_end(fpu_enabled);
return err;
--- a/arch/x86/crypto/serpent_avx2_glue.c
+++ b/arch/x86/crypto/serpent_avx2_glue.c
@@ -167,7 +167,7 @@ static int xts_encrypt(struct skcipher_r
return glue_xts_req_128bit(&serpent_enc_xts, req,
XTS_TWEAK_CAST(__serpent_encrypt),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, false);
}
static int xts_decrypt(struct skcipher_request *req)
@@ -177,7 +177,7 @@ static int xts_decrypt(struct skcipher_r
return glue_xts_req_128bit(&serpent_dec_xts, req,
XTS_TWEAK_CAST(__serpent_encrypt),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, true);
}
static struct skcipher_alg serpent_algs[] = {
--- a/arch/x86/crypto/serpent_avx_glue.c
+++ b/arch/x86/crypto/serpent_avx_glue.c
@@ -207,7 +207,7 @@ static int xts_encrypt(struct skcipher_r
return glue_xts_req_128bit(&serpent_enc_xts, req,
XTS_TWEAK_CAST(__serpent_encrypt),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, false);
}
static int xts_decrypt(struct skcipher_request *req)
@@ -217,7 +217,7 @@ static int xts_decrypt(struct skcipher_r
return glue_xts_req_128bit(&serpent_dec_xts, req,
XTS_TWEAK_CAST(__serpent_encrypt),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, true);
}
static struct skcipher_alg serpent_algs[] = {
--- a/arch/x86/crypto/twofish_avx_glue.c
+++ b/arch/x86/crypto/twofish_avx_glue.c
@@ -210,7 +210,7 @@ static int xts_encrypt(struct skcipher_r
return glue_xts_req_128bit(&twofish_enc_xts, req,
XTS_TWEAK_CAST(twofish_enc_blk),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, false);
}
static int xts_decrypt(struct skcipher_request *req)
@@ -220,7 +220,7 @@ static int xts_decrypt(struct skcipher_r
return glue_xts_req_128bit(&twofish_dec_xts, req,
XTS_TWEAK_CAST(twofish_enc_blk),
- &ctx->tweak_ctx, &ctx->crypt_ctx);
+ &ctx->tweak_ctx, &ctx->crypt_ctx, true);
}
static struct skcipher_alg twofish_algs[] = {
--- a/arch/x86/include/asm/crypto/glue_helper.h
+++ b/arch/x86/include/asm/crypto/glue_helper.h
@@ -114,7 +114,7 @@ extern int glue_ctr_req_128bit(const str
extern int glue_xts_req_128bit(const struct common_glue_ctx *gctx,
struct skcipher_request *req,
common_glue_func_t tweak_fn, void *tweak_ctx,
- void *crypt_ctx);
+ void *crypt_ctx, bool decrypt);
extern void glue_xts_crypt_128bit_one(void *ctx, u128 *dst, const u128 *src,
le128 *iv, common_glue_func_t fn);