[PATCH v6 5/8] crypto: x86/cast6: Remove glue function macro usage
From: Kees Cook
Date: Thu Nov 21 2019 - 20:04:00 EST
In order to remove the callsite function casts, regularize the function
prototypes for helpers to avoid triggering Control-Flow Integrity checks
during indirect function calls. Where needed, to avoid changes to
pointer math, u8 pointers are internally cast back to u128 pointers.
Co-developed-by: JoÃo Moreira <joao.moreira@xxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
arch/x86/crypto/cast6_avx_glue.c | 68 +++++++++++++++-----------------
crypto/cast6_generic.c | 18 +++++----
include/crypto/cast6.h | 4 +-
3 files changed, 43 insertions(+), 47 deletions(-)
diff --git a/arch/x86/crypto/cast6_avx_glue.c b/arch/x86/crypto/cast6_avx_glue.c
index a8a38fffb4a9..da5297475f9e 100644
--- a/arch/x86/crypto/cast6_avx_glue.c
+++ b/arch/x86/crypto/cast6_avx_glue.c
@@ -20,20 +20,17 @@
#define CAST6_PARALLEL_BLOCKS 8
-asmlinkage void cast6_ecb_enc_8way(struct cast6_ctx *ctx, u8 *dst,
- const u8 *src);
-asmlinkage void cast6_ecb_dec_8way(struct cast6_ctx *ctx, u8 *dst,
- const u8 *src);
-
-asmlinkage void cast6_cbc_dec_8way(struct cast6_ctx *ctx, u8 *dst,
- const u8 *src);
-asmlinkage void cast6_ctr_8way(struct cast6_ctx *ctx, u8 *dst, const u8 *src,
+asmlinkage void cast6_ecb_enc_8way(const void *ctx, u8 *dst, const u8 *src);
+asmlinkage void cast6_ecb_dec_8way(const void *ctx, u8 *dst, const u8 *src);
+
+asmlinkage void cast6_cbc_dec_8way(const void *ctx, u8 *dst, const u8 *src);
+asmlinkage void cast6_ctr_8way(const void *ctx, u8 *dst, const u8 *src,
le128 *iv);
-asmlinkage void cast6_xts_enc_8way(struct cast6_ctx *ctx, u8 *dst,
- const u8 *src, le128 *iv);
-asmlinkage void cast6_xts_dec_8way(struct cast6_ctx *ctx, u8 *dst,
- const u8 *src, le128 *iv);
+asmlinkage void cast6_xts_enc_8way(const void *ctx, u8 *dst, const u8 *src,
+ le128 *iv);
+asmlinkage void cast6_xts_dec_8way(const void *ctx, u8 *dst, const u8 *src,
+ le128 *iv);
static int cast6_setkey_skcipher(struct crypto_skcipher *tfm,
const u8 *key, unsigned int keylen)
@@ -41,21 +38,21 @@ static int cast6_setkey_skcipher(struct crypto_skcipher *tfm,
return cast6_setkey(&tfm->base, key, keylen);
}
-static void cast6_xts_enc(void *ctx, u128 *dst, const u128 *src, le128 *iv)
+static void cast6_xts_enc(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
{
- glue_xts_crypt_128bit_one(ctx, dst, src, iv,
- GLUE_FUNC_CAST(__cast6_encrypt));
+ glue_xts_crypt_128bit_one(ctx, dst, src, iv, __cast6_encrypt);
}
-static void cast6_xts_dec(void *ctx, u128 *dst, const u128 *src, le128 *iv)
+static void cast6_xts_dec(const void *ctx, u8 *dst, const u8 *src, le128 *iv)
{
- glue_xts_crypt_128bit_one(ctx, dst, src, iv,
- GLUE_FUNC_CAST(__cast6_decrypt));
+ glue_xts_crypt_128bit_one(ctx, dst, src, iv, __cast6_decrypt);
}
-static void cast6_crypt_ctr(void *ctx, u128 *dst, const u128 *src, le128 *iv)
+static void cast6_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);
@@ -70,10 +67,10 @@ static const struct common_glue_ctx cast6_enc = {
.funcs = { {
.num_blocks = CAST6_PARALLEL_BLOCKS,
- .fn_u = { .ecb = GLUE_FUNC_CAST(cast6_ecb_enc_8way) }
+ .fn_u = { .ecb = cast6_ecb_enc_8way }
}, {
.num_blocks = 1,
- .fn_u = { .ecb = GLUE_FUNC_CAST(__cast6_encrypt) }
+ .fn_u = { .ecb = __cast6_encrypt }
} }
};
@@ -83,10 +80,10 @@ static const struct common_glue_ctx cast6_ctr = {
.funcs = { {
.num_blocks = CAST6_PARALLEL_BLOCKS,
- .fn_u = { .ctr = GLUE_CTR_FUNC_CAST(cast6_ctr_8way) }
+ .fn_u = { .ctr = cast6_ctr_8way }
}, {
.num_blocks = 1,
- .fn_u = { .ctr = GLUE_CTR_FUNC_CAST(cast6_crypt_ctr) }
+ .fn_u = { .ctr = cast6_crypt_ctr }
} }
};
@@ -96,10 +93,10 @@ static const struct common_glue_ctx cast6_enc_xts = {
.funcs = { {
.num_blocks = CAST6_PARALLEL_BLOCKS,
- .fn_u = { .xts = GLUE_XTS_FUNC_CAST(cast6_xts_enc_8way) }
+ .fn_u = { .xts = cast6_xts_enc_8way }
}, {
.num_blocks = 1,
- .fn_u = { .xts = GLUE_XTS_FUNC_CAST(cast6_xts_enc) }
+ .fn_u = { .xts = cast6_xts_enc }
} }
};
@@ -109,10 +106,10 @@ static const struct common_glue_ctx cast6_dec = {
.funcs = { {
.num_blocks = CAST6_PARALLEL_BLOCKS,
- .fn_u = { .ecb = GLUE_FUNC_CAST(cast6_ecb_dec_8way) }
+ .fn_u = { .ecb = cast6_ecb_dec_8way }
}, {
.num_blocks = 1,
- .fn_u = { .ecb = GLUE_FUNC_CAST(__cast6_decrypt) }
+ .fn_u = { .ecb = __cast6_decrypt }
} }
};
@@ -122,10 +119,10 @@ static const struct common_glue_ctx cast6_dec_cbc = {
.funcs = { {
.num_blocks = CAST6_PARALLEL_BLOCKS,
- .fn_u = { .cbc = GLUE_CBC_FUNC_CAST(cast6_cbc_dec_8way) }
+ .fn_u = { .cbc = cast6_cbc_dec_8way }
}, {
.num_blocks = 1,
- .fn_u = { .cbc = GLUE_CBC_FUNC_CAST(__cast6_decrypt) }
+ .fn_u = { .cbc = __cast6_decrypt }
} }
};
@@ -135,10 +132,10 @@ static const struct common_glue_ctx cast6_dec_xts = {
.funcs = { {
.num_blocks = CAST6_PARALLEL_BLOCKS,
- .fn_u = { .xts = GLUE_XTS_FUNC_CAST(cast6_xts_dec_8way) }
+ .fn_u = { .xts = cast6_xts_dec_8way }
}, {
.num_blocks = 1,
- .fn_u = { .xts = GLUE_XTS_FUNC_CAST(cast6_xts_dec) }
+ .fn_u = { .xts = cast6_xts_dec }
} }
};
@@ -154,8 +151,7 @@ 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(__cast6_encrypt),
- req);
+ return glue_cbc_encrypt_req_128bit(__cast6_encrypt, req);
}
static int cbc_decrypt(struct skcipher_request *req)
@@ -199,8 +195,7 @@ static int xts_encrypt(struct skcipher_request *req)
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct cast6_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
- return glue_xts_req_128bit(&cast6_enc_xts, req,
- XTS_TWEAK_CAST(__cast6_encrypt),
+ return glue_xts_req_128bit(&cast6_enc_xts, req, __cast6_encrypt,
&ctx->tweak_ctx, &ctx->crypt_ctx, false);
}
@@ -209,8 +204,7 @@ static int xts_decrypt(struct skcipher_request *req)
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct cast6_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
- return glue_xts_req_128bit(&cast6_dec_xts, req,
- XTS_TWEAK_CAST(__cast6_encrypt),
+ return glue_xts_req_128bit(&cast6_dec_xts, req, __cast6_encrypt,
&ctx->tweak_ctx, &ctx->crypt_ctx, true);
}
diff --git a/crypto/cast6_generic.c b/crypto/cast6_generic.c
index a8248f8e2777..85328522c5ca 100644
--- a/crypto/cast6_generic.c
+++ b/crypto/cast6_generic.c
@@ -154,7 +154,7 @@ int cast6_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
EXPORT_SYMBOL_GPL(cast6_setkey);
/*forward quad round*/
-static inline void Q(u32 *block, u8 *Kr, u32 *Km)
+static inline void Q(u32 *block, const u8 *Kr, const u32 *Km)
{
u32 I;
block[2] ^= F1(block[3], Kr[0], Km[0]);
@@ -164,7 +164,7 @@ static inline void Q(u32 *block, u8 *Kr, u32 *Km)
}
/*reverse quad round*/
-static inline void QBAR(u32 *block, u8 *Kr, u32 *Km)
+static inline void QBAR(u32 *block, const u8 *Kr, const u32 *Km)
{
u32 I;
block[3] ^= F1(block[0], Kr[3], Km[3]);
@@ -173,13 +173,14 @@ static inline void QBAR(u32 *block, u8 *Kr, u32 *Km)
block[2] ^= F1(block[3], Kr[0], Km[0]);
}
-void __cast6_encrypt(struct cast6_ctx *c, u8 *outbuf, const u8 *inbuf)
+void __cast6_encrypt(const void *ctx, u8 *outbuf, const u8 *inbuf)
{
+ const struct cast6_ctx *c = ctx;
const __be32 *src = (const __be32 *)inbuf;
__be32 *dst = (__be32 *)outbuf;
u32 block[4];
- u32 *Km;
- u8 *Kr;
+ const u32 *Km;
+ const u8 *Kr;
block[0] = be32_to_cpu(src[0]);
block[1] = be32_to_cpu(src[1]);
@@ -211,13 +212,14 @@ static void cast6_encrypt(struct crypto_tfm *tfm, u8 *outbuf, const u8 *inbuf)
__cast6_encrypt(crypto_tfm_ctx(tfm), outbuf, inbuf);
}
-void __cast6_decrypt(struct cast6_ctx *c, u8 *outbuf, const u8 *inbuf)
+void __cast6_decrypt(const void *ctx, u8 *outbuf, const u8 *inbuf)
{
+ const struct cast6_ctx *c = ctx;
const __be32 *src = (const __be32 *)inbuf;
__be32 *dst = (__be32 *)outbuf;
u32 block[4];
- u32 *Km;
- u8 *Kr;
+ const u32 *Km;
+ const u8 *Kr;
block[0] = be32_to_cpu(src[0]);
block[1] = be32_to_cpu(src[1]);
diff --git a/include/crypto/cast6.h b/include/crypto/cast6.h
index c71f6ef47f0f..4c8d0c72f78d 100644
--- a/include/crypto/cast6.h
+++ b/include/crypto/cast6.h
@@ -19,7 +19,7 @@ int __cast6_setkey(struct cast6_ctx *ctx, const u8 *key,
unsigned int keylen, u32 *flags);
int cast6_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen);
-void __cast6_encrypt(struct cast6_ctx *ctx, u8 *dst, const u8 *src);
-void __cast6_decrypt(struct cast6_ctx *ctx, u8 *dst, const u8 *src);
+void __cast6_encrypt(const void *ctx, u8 *dst, const u8 *src);
+void __cast6_decrypt(const void *ctx, u8 *dst, const u8 *src);
#endif
--
2.17.1