[v6,1/8] crypto: x86/glue_helper: Regularize function prototypes
diff mbox series

Message ID 20191122010334.12081-2-keescook@chromium.org
State New
Headers show
Series
  • crypto: x86: Fix indirect function call casts
Related show

Commit Message

Kees Cook Nov. 22, 2019, 1:03 a.m. UTC
The crypto glue performed function prototype casting 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
incremental 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: Kees Cook <keescook@chromium.org>
---
 arch/x86/crypto/glue_helper.c             | 23 ++++++++++++++---------
 arch/x86/include/asm/crypto/glue_helper.h | 13 +++++++------
 2 files changed, 21 insertions(+), 15 deletions(-)

Comments

Eric Biggers Nov. 22, 2019, 2:04 a.m. UTC | #1
On Thu, Nov 21, 2019 at 05:03:27PM -0800, Kees Cook wrote:
> The crypto glue performed function prototype casting 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
> incremental 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: Kees Cook <keescook@chromium.org>

Co-developers need their own Signed-off-by.  checkpatch.pl warns about this.

- Eric

Patch
diff mbox series

diff --git a/arch/x86/crypto/glue_helper.c b/arch/x86/crypto/glue_helper.c
index d15b99397480..d3d91a0abf88 100644
--- a/arch/x86/crypto/glue_helper.c
+++ b/arch/x86/crypto/glue_helper.c
@@ -134,7 +134,8 @@  int glue_cbc_decrypt_req_128bit(const struct common_glue_ctx *gctx,
 				src -= num_blocks - 1;
 				dst -= num_blocks - 1;
 
-				gctx->funcs[i].fn_u.cbc(ctx, dst, src);
+				gctx->funcs[i].fn_u.cbc(ctx, (u8 *)dst,
+							(const u8 *)src);
 
 				nbytes -= func_bytes;
 				if (nbytes < bsize)
@@ -188,7 +189,9 @@  int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
 
 			/* Process multi-block batch */
 			do {
-				gctx->funcs[i].fn_u.ctr(ctx, dst, src, &ctrblk);
+				gctx->funcs[i].fn_u.ctr(ctx, (u8 *)dst,
+							(const u8 *)src,
+							&ctrblk);
 				src += num_blocks;
 				dst += num_blocks;
 				nbytes -= func_bytes;
@@ -210,7 +213,8 @@  int glue_ctr_req_128bit(const struct common_glue_ctx *gctx,
 
 		be128_to_le128(&ctrblk, (be128 *)walk.iv);
 		memcpy(&tmp, walk.src.virt.addr, nbytes);
-		gctx->funcs[gctx->num_funcs - 1].fn_u.ctr(ctx, &tmp, &tmp,
+		gctx->funcs[gctx->num_funcs - 1].fn_u.ctr(ctx, (u8 *)&tmp,
+							  (const u8 *)&tmp,
 							  &ctrblk);
 		memcpy(walk.dst.virt.addr, &tmp, nbytes);
 		le128_to_be128((be128 *)walk.iv, &ctrblk);
@@ -240,7 +244,8 @@  static unsigned int __glue_xts_req_128bit(const struct common_glue_ctx *gctx,
 
 		if (nbytes >= func_bytes) {
 			do {
-				gctx->funcs[i].fn_u.xts(ctx, dst, src,
+				gctx->funcs[i].fn_u.xts(ctx, (u8 *)dst,
+							(const u8 *)src,
 							walk->iv);
 
 				src += num_blocks;
@@ -354,8 +359,8 @@  int glue_xts_req_128bit(const struct common_glue_ctx *gctx,
 }
 EXPORT_SYMBOL_GPL(glue_xts_req_128bit);
 
-void glue_xts_crypt_128bit_one(void *ctx, u128 *dst, const u128 *src, le128 *iv,
-			       common_glue_func_t fn)
+void glue_xts_crypt_128bit_one(const void *ctx, u8 *dst, const u8 *src,
+			       le128 *iv, common_glue_func_t fn)
 {
 	le128 ivblk = *iv;
 
@@ -363,13 +368,13 @@  void glue_xts_crypt_128bit_one(void *ctx, u128 *dst, const u128 *src, le128 *iv,
 	gf128mul_x_ble(iv, &ivblk);
 
 	/* CC <- T xor C */
-	u128_xor(dst, src, (u128 *)&ivblk);
+	u128_xor((u128 *)dst, (const u128 *)src, (u128 *)&ivblk);
 
 	/* PP <- D(Key2,CC) */
-	fn(ctx, (u8 *)dst, (u8 *)dst);
+	fn(ctx, dst, dst);
 
 	/* P <- T xor PP */
-	u128_xor(dst, dst, (u128 *)&ivblk);
+	u128_xor((u128 *)dst, (u128 *)dst, (u128 *)&ivblk);
 }
 EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit_one);
 
diff --git a/arch/x86/include/asm/crypto/glue_helper.h b/arch/x86/include/asm/crypto/glue_helper.h
index 8d4a8e1226ee..ba48d5af4f16 100644
--- a/arch/x86/include/asm/crypto/glue_helper.h
+++ b/arch/x86/include/asm/crypto/glue_helper.h
@@ -11,11 +11,11 @@ 
 #include <asm/fpu/api.h>
 #include <crypto/b128ops.h>
 
-typedef void (*common_glue_func_t)(void *ctx, u8 *dst, const u8 *src);
-typedef void (*common_glue_cbc_func_t)(void *ctx, u128 *dst, const u128 *src);
-typedef void (*common_glue_ctr_func_t)(void *ctx, u128 *dst, const u128 *src,
+typedef void (*common_glue_func_t)(const void *ctx, u8 *dst, const u8 *src);
+typedef void (*common_glue_cbc_func_t)(const void *ctx, u8 *dst, const u8 *src);
+typedef void (*common_glue_ctr_func_t)(const void *ctx, u8 *dst, const u8 *src,
 				       le128 *iv);
-typedef void (*common_glue_xts_func_t)(void *ctx, u128 *dst, const u128 *src,
+typedef void (*common_glue_xts_func_t)(const void *ctx, u8 *dst, const u8 *src,
 				       le128 *iv);
 
 #define GLUE_FUNC_CAST(fn) ((common_glue_func_t)(fn))
@@ -116,7 +116,8 @@  extern int glue_xts_req_128bit(const struct common_glue_ctx *gctx,
 			       common_glue_func_t tweak_fn, void *tweak_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);
+extern void glue_xts_crypt_128bit_one(const void *ctx, u8 *dst,
+				      const u8 *src, le128 *iv,
+				      common_glue_func_t fn);
 
 #endif /* _CRYPTO_GLUE_HELPER_H */