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, 31 insertions, 32 deletions

diff --git a/arch/x86/crypto/serpent_avx_glue.c b/arch/x86/crypto/serpent_avx_glue.c
index 7d3dca38a5a2..7806d1cbe854 100644
--- a/arch/x86/crypto/serpent_avx_glue.c
+++ b/arch/x86/crypto/serpent_avx_glue.c
@@ -20,33 +20,35 @@
 #include <asm/crypto/serpent-avx.h>
 
 /* 8-way parallel cipher functions */
-asmlinkage void serpent_ecb_enc_8way_avx(struct serpent_ctx *ctx, u8 *dst,
+asmlinkage void serpent_ecb_enc_8way_avx(const void *ctx, u8 *dst,
 					 const u8 *src);
 EXPORT_SYMBOL_GPL(serpent_ecb_enc_8way_avx);
 
-asmlinkage void serpent_ecb_dec_8way_avx(struct serpent_ctx *ctx, u8 *dst,
+asmlinkage void serpent_ecb_dec_8way_avx(const void *ctx, u8 *dst,
 					 const u8 *src);
 EXPORT_SYMBOL_GPL(serpent_ecb_dec_8way_avx);
 
-asmlinkage void serpent_cbc_dec_8way_avx(struct serpent_ctx *ctx, u8 *dst,
+asmlinkage void serpent_cbc_dec_8way_avx(const void *ctx, u8 *dst,
 					 const u8 *src);
 EXPORT_SYMBOL_GPL(serpent_cbc_dec_8way_avx);
 
-asmlinkage void serpent_ctr_8way_avx(struct serpent_ctx *ctx, u8 *dst,
-				     const u8 *src, le128 *iv);
+asmlinkage void serpent_ctr_8way_avx(const void *ctx, u8 *dst, const u8 *src,
+				     le128 *iv);
 EXPORT_SYMBOL_GPL(serpent_ctr_8way_avx);
 
-asmlinkage void serpent_xts_enc_8way_avx(struct serpent_ctx *ctx, u8 *dst,
+asmlinkage void serpent_xts_enc_8way_avx(const void *ctx, u8 *dst,
 					 const u8 *src, le128 *iv);
 EXPORT_SYMBOL_GPL(serpent_xts_enc_8way_avx);
 
-asmlinkage void serpent_xts_dec_8way_avx(struct serpent_ctx *ctx, u8 *dst,
+asmlinkage void serpent_xts_dec_8way_avx(const void *ctx, u8 *dst,
 					 const u8 *src, le128 *iv);
 EXPORT_SYMBOL_GPL(serpent_xts_dec_8way_avx);
 
-void __serpent_crypt_ctr(void *ctx, u128 *dst, const u128 *src, le128 *iv)
+void __serpent_crypt_ctr(const void *ctx, u8 *d, const u8 *s, le128 *iv)
 {
 	be128 ctrblk;
+	u128 *dst = (u128 *)d;
+	const u128 *src = (const u128 *)s;
 
 	le128_to_be128(&ctrblk, iv);
 	le128_inc(iv);
@@ -56,17 +58,15 @@ void __serpent_crypt_ctr(void *ctx, u128 *dst, const u128 *src, le128 *iv)
 }
 EXPORT_SYMBOL_GPL(__serpent_crypt_ctr);
 
-void serpent_xts_enc(void *ctx, u128 *dst, const u128 *src, le128 *iv)
+void serpent_xts_enc(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
 {
-	glue_xts_crypt_128bit_one(ctx, dst, src, iv,
-				  GLUE_FUNC_CAST(__serpent_encrypt));
+	glue_xts_crypt_128bit_one(ctx, dst, src, iv, __serpent_encrypt);
 }
 EXPORT_SYMBOL_GPL(serpent_xts_enc);
 
-void serpent_xts_dec(void *ctx, u128 *dst, const u128 *src, le128 *iv)
+void serpent_xts_dec(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
 {
-	glue_xts_crypt_128bit_one(ctx, dst, src, iv,
-				  GLUE_FUNC_CAST(__serpent_decrypt));
+	glue_xts_crypt_128bit_one(ctx, dst, src, iv, __serpent_decrypt);
 }
 EXPORT_SYMBOL_GPL(serpent_xts_dec);
 
@@ -102,10 +102,10 @@ static const struct common_glue_ctx serpent_enc = {
 
 	.funcs = { {
 		.num_blocks = SERPENT_PARALLEL_BLOCKS,
-		.fn_u = { .ecb = GLUE_FUNC_CAST(serpent_ecb_enc_8way_avx) }
+		.fn_u = { .ecb = serpent_ecb_enc_8way_avx }
 	}, {
 		.num_blocks = 1,
-		.fn_u = { .ecb = GLUE_FUNC_CAST(__serpent_encrypt) }
+		.fn_u = { .ecb = __serpent_encrypt }
 	} }
 };
 
@@ -115,10 +115,10 @@ static const struct common_glue_ctx serpent_ctr = {
 
 	.funcs = { {
 		.num_blocks = SERPENT_PARALLEL_BLOCKS,
-		.fn_u = { .ctr = GLUE_CTR_FUNC_CAST(serpent_ctr_8way_avx) }
+		.fn_u = { .ctr = serpent_ctr_8way_avx }
 	}, {
 		.num_blocks = 1,
-		.fn_u = { .ctr = GLUE_CTR_FUNC_CAST(__serpent_crypt_ctr) }
+		.fn_u = { .ctr = __serpent_crypt_ctr }
 	} }
 };
 
@@ -128,10 +128,10 @@ static const struct common_glue_ctx serpent_enc_xts = {
 
 	.funcs = { {
 		.num_blocks = SERPENT_PARALLEL_BLOCKS,
-		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(serpent_xts_enc_8way_avx) }
+		.fn_u = { .xts = serpent_xts_enc_8way_avx }
 	}, {
 		.num_blocks = 1,
-		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(serpent_xts_enc) }
+		.fn_u = { .xts = serpent_xts_enc }
 	} }
 };
 
@@ -141,10 +141,10 @@ static const struct common_glue_ctx serpent_dec = {
 
 	.funcs = { {
 		.num_blocks = SERPENT_PARALLEL_BLOCKS,
-		.fn_u = { .ecb = GLUE_FUNC_CAST(serpent_ecb_dec_8way_avx) }
+		.fn_u = { .ecb = serpent_ecb_dec_8way_avx }
 	}, {
 		.num_blocks = 1,
-		.fn_u = { .ecb = GLUE_FUNC_CAST(__serpent_decrypt) }
+		.fn_u = { .ecb = __serpent_decrypt }
 	} }
 };
 
@@ -154,10 +154,10 @@ static const struct common_glue_ctx serpent_dec_cbc = {
 
 	.funcs = { {
 		.num_blocks = SERPENT_PARALLEL_BLOCKS,
-		.fn_u = { .cbc = GLUE_CBC_FUNC_CAST(serpent_cbc_dec_8way_avx) }
+		.fn_u = { .cbc = serpent_cbc_dec_8way_avx }
 	}, {
 		.num_blocks = 1,
-		.fn_u = { .cbc = GLUE_CBC_FUNC_CAST(__serpent_decrypt) }
+		.fn_u = { .cbc = __serpent_decrypt }
 	} }
 };
 
@@ -167,10 +167,10 @@ static const struct common_glue_ctx serpent_dec_xts = {
 
 	.funcs = { {
 		.num_blocks = SERPENT_PARALLEL_BLOCKS,
-		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(serpent_xts_dec_8way_avx) }
+		.fn_u = { .xts = serpent_xts_dec_8way_avx }
 	}, {
 		.num_blocks = 1,
-		.fn_u = { .xts = GLUE_XTS_FUNC_CAST(serpent_xts_dec) }
+		.fn_u = { .xts = serpent_xts_dec }
 	} }
 };
 
@@ -186,8 +186,7 @@ static int ecb_decrypt(struct skcipher_request *req)
 
 static int cbc_encrypt(struct skcipher_request *req)
 {
-	return glue_cbc_encrypt_req_128bit(GLUE_FUNC_CAST(__serpent_encrypt),
-					   req);
+	return glue_cbc_encrypt_req_128bit(__serpent_encrypt, req);
 }
 
 static int cbc_decrypt(struct skcipher_request *req)
@@ -206,8 +205,8 @@ static int xts_encrypt(struct skcipher_request *req)
 	struct serpent_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
 
 	return glue_xts_req_128bit(&serpent_enc_xts, req,
-				   XTS_TWEAK_CAST(__serpent_encrypt),
-				   &ctx->tweak_ctx, &ctx->crypt_ctx, false);
+				   __serpent_encrypt, &ctx->tweak_ctx,
+				   &ctx->crypt_ctx, false);
 }
 
 static int xts_decrypt(struct skcipher_request *req)
@@ -216,8 +215,8 @@ static int xts_decrypt(struct skcipher_request *req)
 	struct serpent_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
 
 	return glue_xts_req_128bit(&serpent_dec_xts, req,
-				   XTS_TWEAK_CAST(__serpent_encrypt),
-				   &ctx->tweak_ctx, &ctx->crypt_ctx, true);
+				   __serpent_encrypt, &ctx->tweak_ctx,
+				   &ctx->crypt_ctx, true);
 }
 
 static struct skcipher_alg serpent_algs[] = {