crypto: x86 - Regularize glue function prototypes

The crypto glue performed function prototype casting via macros to make
indirect calls to assembly routines. Instead of performing casts at the
call sites (which trips Control Flow Integrity prototype checking), switch
each prototype to a common standard set of arguments which allows the
removal of the existing macros. In order to keep pointer math unchanged,
internal casting between u128 pointers and u8 pointers is added.

Co-developed-by: João Moreira <joao.moreira@intel.com>
Signed-off-by: João Moreira <joao.moreira@intel.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 18 insertions, 27 deletions

diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
index 3e707e81afdb..670f8fcf2544 100644
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -83,10 +83,8 @@ struct gcm_context_data {
 
 asmlinkage int aesni_set_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
 			     unsigned int key_len);
-asmlinkage void aesni_enc(struct crypto_aes_ctx *ctx, u8 *out,
-			  const u8 *in);
-asmlinkage void aesni_dec(struct crypto_aes_ctx *ctx, u8 *out,
-			  const u8 *in);
+asmlinkage void aesni_enc(const void *ctx, u8 *out, const u8 *in);
+asmlinkage void aesni_dec(const void *ctx, u8 *out, const u8 *in);
 asmlinkage void aesni_ecb_enc(struct crypto_aes_ctx *ctx, u8 *out,
 			      const u8 *in, unsigned int len);
 asmlinkage void aesni_ecb_dec(struct crypto_aes_ctx *ctx, u8 *out,
@@ -106,8 +104,8 @@ static void (*aesni_ctr_enc_tfm)(struct crypto_aes_ctx *ctx, u8 *out,
 asmlinkage void aesni_ctr_enc(struct crypto_aes_ctx *ctx, u8 *out,
 			      const u8 *in, unsigned int len, u8 *iv);
 
-asmlinkage void aesni_xts_crypt8(struct crypto_aes_ctx *ctx, u8 *out,
-				 const u8 *in, bool enc, u8 *iv);
+asmlinkage void aesni_xts_crypt8(const struct crypto_aes_ctx *ctx, u8 *out,
+				 const u8 *in, bool enc, le128 *iv);
 
 /* asmlinkage void aesni_gcm_enc()
  * void *ctx,  AES Key schedule. Starts on a 16 byte boundary.
@@ -550,29 +548,24 @@ static int xts_aesni_setkey(struct crypto_skcipher *tfm, const u8 *key,
 }
 
 
-static void aesni_xts_tweak(void *ctx, u8 *out, const u8 *in)
+static void aesni_xts_enc(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
 {
-	aesni_enc(ctx, out, in);
+	glue_xts_crypt_128bit_one(ctx, dst, src, iv, aesni_enc);
 }
 
-static void aesni_xts_enc(void *ctx, u128 *dst, const u128 *src, le128 *iv)
+static void aesni_xts_dec(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
 {
-	glue_xts_crypt_128bit_one(ctx, dst, src, iv, GLUE_FUNC_CAST(aesni_enc));
+	glue_xts_crypt_128bit_one(ctx, dst, src, iv, aesni_dec);
 }
 
-static void aesni_xts_dec(void *ctx, u128 *dst, const u128 *src, le128 *iv)
+static void aesni_xts_enc8(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
 {
-	glue_xts_crypt_128bit_one(ctx, dst, src, iv, GLUE_FUNC_CAST(aesni_dec));
+	aesni_xts_crypt8(ctx, dst, src, true, iv);
 }
 
-static void aesni_xts_enc8(void *ctx, u128 *dst, const u128 *src, le128 *iv)
+static void aesni_xts_dec8(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
 {
-	aesni_xts_crypt8(ctx, (u8 *)dst, (const u8 *)src, true, (u8 *)iv);
-}
-
-static void aesni_xts_dec8(void *ctx, u128 *dst, const u128 *src, le128 *iv)
-{
-	aesni_xts_crypt8(ctx, (u8 *)dst, (const u8 *)src, false, (u8 *)iv);
+	aesni_xts_crypt8(ctx, dst, src, false, iv);
 }
 
 static const struct common_glue_ctx aesni_enc_xts = {
@@ -581,10 +574,10 @@ static const struct common_glue_ctx aesni_enc_xts = {
 
 	.funcs = { {
 		.num_blocks = 8,
-		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(aesni_xts_enc8) }
+		.fn_u = { .xts = aesni_xts_enc8 }
 	}, {
 		.num_blocks = 1,
-		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(aesni_xts_enc) }
+		.fn_u = { .xts = aesni_xts_enc }
 	} }
 };
 
@@ -594,10 +587,10 @@ static const struct common_glue_ctx aesni_dec_xts = {
 
 	.funcs = { {
 		.num_blocks = 8,
-		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(aesni_xts_dec8) }
+		.fn_u = { .xts = aesni_xts_dec8 }
 	}, {
 		.num_blocks = 1,
-		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(aesni_xts_dec) }
+		.fn_u = { .xts = aesni_xts_dec }
 	} }
 };
 
@@ -606,8 +599,7 @@ static int xts_encrypt(struct skcipher_request *req)
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	struct aesni_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
 
-	return glue_xts_req_128bit(&aesni_enc_xts, req,
-				   XTS_TWEAK_CAST(aesni_xts_tweak),
+	return glue_xts_req_128bit(&aesni_enc_xts, req, aesni_enc,
 				   aes_ctx(ctx->raw_tweak_ctx),
 				   aes_ctx(ctx->raw_crypt_ctx),
 				   false);
@@ -618,8 +610,7 @@ static int xts_decrypt(struct skcipher_request *req)
 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 	struct aesni_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
 
-	return glue_xts_req_128bit(&aesni_dec_xts, req,
-				   XTS_TWEAK_CAST(aesni_xts_tweak),
+	return glue_xts_req_128bit(&aesni_dec_xts, req, aesni_enc,
 				   aes_ctx(ctx->raw_tweak_ctx),
 				   aes_ctx(ctx->raw_crypt_ctx),
 				   true);