diff options
| -rw-r--r-- | arch/x86/crypto/twofish_glue_3way.c | 119 |
1 files changed, 117 insertions, 2 deletions
diff --git a/arch/x86/crypto/twofish_glue_3way.c b/arch/x86/crypto/twofish_glue_3way.c index fa9151df3637..954f59eeb7b4 100644 --- a/arch/x86/crypto/twofish_glue_3way.c +++ b/arch/x86/crypto/twofish_glue_3way.c @@ -33,11 +33,16 @@ #include <crypto/twofish.h> #include <crypto/b128ops.h> #include <crypto/lrw.h> +#include <crypto/xts.h> #if defined(CONFIG_CRYPTO_LRW) || defined(CONFIG_CRYPTO_LRW_MODULE) #define HAS_LRW #endif +#if defined(CONFIG_CRYPTO_XTS) || defined(CONFIG_CRYPTO_XTS_MODULE) +#define HAS_XTS +#endif + /* regular block cipher functions from twofish_x86_64 module */ asmlinkage void twofish_enc_blk(struct twofish_ctx *ctx, u8 *dst, const u8 *src); @@ -437,7 +442,7 @@ static struct crypto_alg blk_ctr_alg = { }, }; -#ifdef HAS_LRW +#if defined(HAS_LRW) || defined(HAS_XTS) static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { @@ -469,6 +474,10 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) twofish_dec_blk(ctx, srcdst, srcdst); } +#endif + +#ifdef HAS_LRW + struct twofish_lrw_ctx { struct lrw_table_ctx lrw_table; struct twofish_ctx twofish_ctx; @@ -555,6 +564,99 @@ static struct crypto_alg blk_lrw_alg = { #endif +#ifdef HAS_XTS + +struct twofish_xts_ctx { + struct twofish_ctx tweak_ctx; + struct twofish_ctx crypt_ctx; +}; + +static int xts_twofish_setkey(struct crypto_tfm *tfm, const u8 *key, + unsigned int keylen) +{ + struct twofish_xts_ctx *ctx = crypto_tfm_ctx(tfm); + u32 *flags = &tfm->crt_flags; + int err; + + /* key consists of keys of equal size concatenated, therefore + * the length must be even + */ + if (keylen % 2) { + *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; + return -EINVAL; + } + + /* first half of xts-key is for crypt */ + err = __twofish_setkey(&ctx->crypt_ctx, key, keylen / 2, flags); + if (err) + return err; + + /* second half of xts-key is for tweak */ + return __twofish_setkey(&ctx->tweak_ctx, key + keylen / 2, keylen / 2, + flags); +} + +static int xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, + struct scatterlist *src, unsigned int nbytes) +{ + struct twofish_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); + be128 buf[3]; + struct xts_crypt_req req = { + .tbuf = buf, + .tbuflen = sizeof(buf), + + .tweak_ctx = &ctx->tweak_ctx, + .tweak_fn = XTS_TWEAK_CAST(twofish_enc_blk), + .crypt_ctx = &ctx->crypt_ctx, + .crypt_fn = encrypt_callback, + }; + + return xts_crypt(desc, dst, src, nbytes, &req); +} + +static int xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, + struct scatterlist *src, unsigned int nbytes) +{ + struct twofish_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); + be128 buf[3]; + struct xts_crypt_req req = { + .tbuf = buf, + .tbuflen = sizeof(buf), + + .tweak_ctx = &ctx->tweak_ctx, + .tweak_fn = XTS_TWEAK_CAST(twofish_enc_blk), + .crypt_ctx = &ctx->crypt_ctx, + .crypt_fn = decrypt_callback, + }; + + return xts_crypt(desc, dst, src, nbytes, &req); +} + +static struct crypto_alg blk_xts_alg = { + .cra_name = "xts(twofish)", + .cra_driver_name = "xts-twofish-3way", + .cra_priority = 300, + .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, + .cra_blocksize = TF_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct twofish_xts_ctx), + .cra_alignmask = 0, + .cra_type = &crypto_blkcipher_type, + .cra_module = THIS_MODULE, + .cra_list = LIST_HEAD_INIT(blk_xts_alg.cra_list), + .cra_u = { + .blkcipher = { + .min_keysize = TF_MIN_KEY_SIZE * 2, + .max_keysize = TF_MAX_KEY_SIZE * 2, + .ivsize = TF_BLOCK_SIZE, + .setkey = xts_twofish_setkey, + .encrypt = xts_encrypt, + .decrypt = xts_decrypt, + }, + }, +}; + +#endif + int __init init(void) { int err; @@ -573,13 +675,23 @@ int __init init(void) if (err) goto blk_lrw_err; #endif +#ifdef HAS_XTS + err = crypto_register_alg(&blk_xts_alg); + if (err) + goto blk_xts_err; +#endif return 0; +#ifdef HAS_XTS + crypto_unregister_alg(&blk_xts_alg); +blk_xts_err: +#endif #ifdef HAS_LRW + crypto_unregister_alg(&blk_lrw_alg); blk_lrw_err: - crypto_unregister_alg(&blk_ctr_alg); #endif + crypto_unregister_alg(&blk_ctr_alg); ctr_err: crypto_unregister_alg(&blk_cbc_alg); cbc_err: @@ -590,6 +702,9 @@ ecb_err: void __exit fini(void) { +#ifdef HAS_XTS + crypto_unregister_alg(&blk_xts_alg); +#endif #ifdef HAS_LRW crypto_unregister_alg(&blk_lrw_alg); #endif |