diff options
| -rw-r--r-- | crypto/keywrap.c | 84 |
1 files changed, 26 insertions, 58 deletions
diff --git a/crypto/keywrap.c b/crypto/keywrap.c index 72014f963ba7..744e35134c45 100644 --- a/crypto/keywrap.c +++ b/crypto/keywrap.c @@ -93,18 +93,10 @@ struct crypto_kw_ctx { struct crypto_kw_block { #define SEMIBSIZE 8 - u8 A[SEMIBSIZE]; - u8 R[SEMIBSIZE]; + __be64 A; + __be64 R; }; -/* convert 64 bit integer into its string representation */ -static inline void crypto_kw_cpu_to_be64(u64 val, u8 *buf) -{ - __be64 *a = (__be64 *)buf; - - *a = cpu_to_be64(val); -} - /* * Fast forward the SGL to the "end" length minus SEMIBSIZE. * The start in the SGL defined by the fast-forward is returned with @@ -139,17 +131,10 @@ static int crypto_kw_decrypt(struct blkcipher_desc *desc, struct crypto_blkcipher *tfm = desc->tfm; struct crypto_kw_ctx *ctx = crypto_blkcipher_ctx(tfm); struct crypto_cipher *child = ctx->child; - - unsigned long alignmask = max_t(unsigned long, SEMIBSIZE, - crypto_cipher_alignmask(child)); - unsigned int i; - - u8 blockbuf[sizeof(struct crypto_kw_block) + alignmask]; - struct crypto_kw_block *block = (struct crypto_kw_block *) - PTR_ALIGN(blockbuf + 0, alignmask + 1); - - u64 t = 6 * ((nbytes) >> 3); + struct crypto_kw_block block; struct scatterlist *lsrc, *ldst; + u64 t = 6 * ((nbytes) >> 3); + unsigned int i; int ret = 0; /* @@ -160,7 +145,7 @@ static int crypto_kw_decrypt(struct blkcipher_desc *desc, return -EINVAL; /* Place the IV into block A */ - memcpy(block->A, desc->info, SEMIBSIZE); + memcpy(&block.A, desc->info, SEMIBSIZE); /* * src scatterlist is read-only. dst scatterlist is r/w. During the @@ -171,32 +156,27 @@ static int crypto_kw_decrypt(struct blkcipher_desc *desc, ldst = dst; for (i = 0; i < 6; i++) { - u8 tbe_buffer[SEMIBSIZE + alignmask]; - /* alignment for the crypto_xor and the _to_be64 operation */ - u8 *tbe = PTR_ALIGN(tbe_buffer + 0, alignmask + 1); - unsigned int tmp_nbytes = nbytes; struct scatter_walk src_walk, dst_walk; + unsigned int tmp_nbytes = nbytes; while (tmp_nbytes) { /* move pointer by tmp_nbytes in the SGL */ crypto_kw_scatterlist_ff(&src_walk, lsrc, tmp_nbytes); /* get the source block */ - scatterwalk_copychunks(block->R, &src_walk, SEMIBSIZE, + scatterwalk_copychunks(&block.R, &src_walk, SEMIBSIZE, false); - /* perform KW operation: get counter as byte string */ - crypto_kw_cpu_to_be64(t, tbe); /* perform KW operation: modify IV with counter */ - crypto_xor(block->A, tbe, SEMIBSIZE); + block.A ^= cpu_to_be64(t); t--; /* perform KW operation: decrypt block */ - crypto_cipher_decrypt_one(child, (u8*)block, - (u8*)block); + crypto_cipher_decrypt_one(child, (u8*)&block, + (u8*)&block); /* move pointer by tmp_nbytes in the SGL */ crypto_kw_scatterlist_ff(&dst_walk, ldst, tmp_nbytes); /* Copy block->R into place */ - scatterwalk_copychunks(block->R, &dst_walk, SEMIBSIZE, + scatterwalk_copychunks(&block.R, &dst_walk, SEMIBSIZE, true); tmp_nbytes -= SEMIBSIZE; @@ -208,11 +188,10 @@ static int crypto_kw_decrypt(struct blkcipher_desc *desc, } /* Perform authentication check */ - if (crypto_memneq("\xA6\xA6\xA6\xA6\xA6\xA6\xA6\xA6", block->A, - SEMIBSIZE)) + if (block.A != cpu_to_be64(0xa6a6a6a6a6a6a6a6)) ret = -EBADMSG; - memzero_explicit(block, sizeof(struct crypto_kw_block)); + memzero_explicit(&block, sizeof(struct crypto_kw_block)); return ret; } @@ -224,17 +203,10 @@ static int crypto_kw_encrypt(struct blkcipher_desc *desc, struct crypto_blkcipher *tfm = desc->tfm; struct crypto_kw_ctx *ctx = crypto_blkcipher_ctx(tfm); struct crypto_cipher *child = ctx->child; - - unsigned long alignmask = max_t(unsigned long, SEMIBSIZE, - crypto_cipher_alignmask(child)); - unsigned int i; - - u8 blockbuf[sizeof(struct crypto_kw_block) + alignmask]; - struct crypto_kw_block *block = (struct crypto_kw_block *) - PTR_ALIGN(blockbuf + 0, alignmask + 1); - - u64 t = 1; + struct crypto_kw_block block; struct scatterlist *lsrc, *ldst; + u64 t = 1; + unsigned int i; /* * Require at least 2 semiblocks (note, the 3rd semiblock that is @@ -249,7 +221,7 @@ static int crypto_kw_encrypt(struct blkcipher_desc *desc, * Place the predefined IV into block A -- for encrypt, the caller * does not need to provide an IV, but he needs to fetch the final IV. */ - memcpy(block->A, "\xA6\xA6\xA6\xA6\xA6\xA6\xA6\xA6", SEMIBSIZE); + block.A = cpu_to_be64(0xa6a6a6a6a6a6a6a6); /* * src scatterlist is read-only. dst scatterlist is r/w. During the @@ -260,30 +232,26 @@ static int crypto_kw_encrypt(struct blkcipher_desc *desc, ldst = dst; for (i = 0; i < 6; i++) { - u8 tbe_buffer[SEMIBSIZE + alignmask]; - u8 *tbe = PTR_ALIGN(tbe_buffer + 0, alignmask + 1); - unsigned int tmp_nbytes = nbytes; struct scatter_walk src_walk, dst_walk; + unsigned int tmp_nbytes = nbytes; scatterwalk_start(&src_walk, lsrc); scatterwalk_start(&dst_walk, ldst); while (tmp_nbytes) { /* get the source block */ - scatterwalk_copychunks(block->R, &src_walk, SEMIBSIZE, + scatterwalk_copychunks(&block.R, &src_walk, SEMIBSIZE, false); /* perform KW operation: encrypt block */ - crypto_cipher_encrypt_one(child, (u8 *)block, - (u8 *)block); - /* perform KW operation: get counter as byte string */ - crypto_kw_cpu_to_be64(t, tbe); + crypto_cipher_encrypt_one(child, (u8 *)&block, + (u8 *)&block); /* perform KW operation: modify IV with counter */ - crypto_xor(block->A, tbe, SEMIBSIZE); + block.A ^= cpu_to_be64(t); t++; /* Copy block->R into place */ - scatterwalk_copychunks(block->R, &dst_walk, SEMIBSIZE, + scatterwalk_copychunks(&block.R, &dst_walk, SEMIBSIZE, true); tmp_nbytes -= SEMIBSIZE; @@ -295,9 +263,9 @@ static int crypto_kw_encrypt(struct blkcipher_desc *desc, } /* establish the IV for the caller to pick up */ - memcpy(desc->info, block->A, SEMIBSIZE); + memcpy(desc->info, &block.A, SEMIBSIZE); - memzero_explicit(block, sizeof(struct crypto_kw_block)); + memzero_explicit(&block, sizeof(struct crypto_kw_block)); return 0; } |