X-Git-Url: http://git.cascardo.info/?a=blobdiff_plain;f=crypto%2Flrw.c;h=ba42acc4deba8059c65dff053faef591e3175517;hb=408e057870c8680a50963b08f9f7efaa151a74ec;hp=358f80be2bf97d128ebd648887325a01ea051a70;hpb=e161183ba674f97fce748384f5bb037d07bdc5c9;p=cascardo%2Flinux.git diff --git a/crypto/lrw.c b/crypto/lrw.c index 358f80be2bf9..ba42acc4deba 100644 --- a/crypto/lrw.c +++ b/crypto/lrw.c @@ -3,7 +3,7 @@ * * Copyright (c) 2006 Rik Snel * - * Based om ecb.c + * Based on ecb.c * Copyright (c) 2006 Herbert Xu * * This program is free software; you can redistribute it and/or modify it @@ -16,6 +16,7 @@ * http://www.mail-archive.com/stds-p1619@listserv.ieee.org/msg00173.html * * The test vectors are included in the testing module tcrypt.[ch] */ + #include #include #include @@ -26,21 +27,11 @@ #include #include +#include struct priv { struct crypto_cipher *child; - /* optimizes multiplying a random (non incrementing, as at the - * start of a new sector) value with key2, we could also have - * used 4k optimization tables or no optimization at all. In the - * latter case we would have to store key2 here */ - struct gf128mul_64k *table; - /* stores: - * key2*{ 0,0,...0,0,0,0,1 }, key2*{ 0,0,...0,0,0,1,1 }, - * key2*{ 0,0,...0,0,1,1,1 }, key2*{ 0,0,...0,1,1,1,1 } - * key2*{ 0,0,...1,1,1,1,1 }, etc - * needed for optimized multiplication of incrementing values - * with key2 */ - be128 mulinc[128]; + struct lrw_table_ctx table; }; static inline void setbit128_bbe(void *b, int bit) @@ -54,28 +45,16 @@ static inline void setbit128_bbe(void *b, int bit) ), b); } -static int setkey(struct crypto_tfm *parent, const u8 *key, - unsigned int keylen) +int lrw_init_table(struct lrw_table_ctx *ctx, const u8 *tweak) { - struct priv *ctx = crypto_tfm_ctx(parent); - struct crypto_cipher *child = ctx->child; - int err, i; be128 tmp = { 0 }; - int bsize = crypto_cipher_blocksize(child); - - crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); - crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) & - CRYPTO_TFM_REQ_MASK); - if ((err = crypto_cipher_setkey(child, key, keylen - bsize))) - return err; - crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) & - CRYPTO_TFM_RES_MASK); + int i; if (ctx->table) gf128mul_free_64k(ctx->table); /* initialize multiplication table for Key2 */ - ctx->table = gf128mul_init_64k_bbe((be128 *)(key + keylen - bsize)); + ctx->table = gf128mul_init_64k_bbe((be128 *)tweak); if (!ctx->table) return -ENOMEM; @@ -88,6 +67,34 @@ static int setkey(struct crypto_tfm *parent, const u8 *key, return 0; } +EXPORT_SYMBOL_GPL(lrw_init_table); + +void lrw_free_table(struct lrw_table_ctx *ctx) +{ + if (ctx->table) + gf128mul_free_64k(ctx->table); +} +EXPORT_SYMBOL_GPL(lrw_free_table); + +static int setkey(struct crypto_tfm *parent, const u8 *key, + unsigned int keylen) +{ + struct priv *ctx = crypto_tfm_ctx(parent); + struct crypto_cipher *child = ctx->child; + int err, bsize = LRW_BLOCK_SIZE; + const u8 *tweak = key + keylen - bsize; + + crypto_cipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_cipher_set_flags(child, crypto_tfm_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + err = crypto_cipher_setkey(child, key, keylen - bsize); + if (err) + return err; + crypto_tfm_set_flags(parent, crypto_cipher_get_flags(child) & + CRYPTO_TFM_RES_MASK); + + return lrw_init_table(&ctx->table, tweak); +} struct sinfo { be128 t; @@ -134,7 +141,7 @@ static int crypt(struct blkcipher_desc *d, { int err; unsigned int avail; - const int bs = crypto_cipher_blocksize(ctx->child); + const int bs = LRW_BLOCK_SIZE; struct sinfo s = { .tfm = crypto_cipher_tfm(ctx->child), .fn = fn @@ -155,7 +162,7 @@ static int crypt(struct blkcipher_desc *d, s.t = *iv; /* T <- I*Key2 */ - gf128mul_64k_bbe(&s.t, ctx->table); + gf128mul_64k_bbe(&s.t, ctx->table.table); goto first; @@ -163,7 +170,8 @@ static int crypt(struct blkcipher_desc *d, do { /* T <- I*Key2, using the optimization * discussed in the specification */ - be128_xor(&s.t, &s.t, &ctx->mulinc[get_index128(iv)]); + be128_xor(&s.t, &s.t, + &ctx->table.mulinc[get_index128(iv)]); inc(iv); first: @@ -206,6 +214,85 @@ static int decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, crypto_cipher_alg(ctx->child)->cia_decrypt); } +int lrw_crypt(struct blkcipher_desc *desc, struct scatterlist *sdst, + struct scatterlist *ssrc, unsigned int nbytes, + struct lrw_crypt_req *req) +{ + const unsigned int bsize = LRW_BLOCK_SIZE; + const unsigned int max_blks = req->tbuflen / bsize; + struct lrw_table_ctx *ctx = req->table_ctx; + struct blkcipher_walk walk; + unsigned int nblocks; + be128 *iv, *src, *dst, *t; + be128 *t_buf = req->tbuf; + int err, i; + + BUG_ON(max_blks < 1); + + blkcipher_walk_init(&walk, sdst, ssrc, nbytes); + + err = blkcipher_walk_virt(desc, &walk); + nbytes = walk.nbytes; + if (!nbytes) + return err; + + nblocks = min(walk.nbytes / bsize, max_blks); + src = (be128 *)walk.src.virt.addr; + dst = (be128 *)walk.dst.virt.addr; + + /* calculate first value of T */ + iv = (be128 *)walk.iv; + t_buf[0] = *iv; + + /* T <- I*Key2 */ + gf128mul_64k_bbe(&t_buf[0], ctx->table); + + i = 0; + goto first; + + for (;;) { + do { + for (i = 0; i < nblocks; i++) { + /* T <- I*Key2, using the optimization + * discussed in the specification */ + be128_xor(&t_buf[i], t, + &ctx->mulinc[get_index128(iv)]); + inc(iv); +first: + t = &t_buf[i]; + + /* PP <- T xor P */ + be128_xor(dst + i, t, src + i); + } + + /* CC <- E(Key2,PP) */ + req->crypt_fn(req->crypt_ctx, (u8 *)dst, + nblocks * bsize); + + /* C <- T xor CC */ + for (i = 0; i < nblocks; i++) + be128_xor(dst + i, dst + i, &t_buf[i]); + + src += nblocks; + dst += nblocks; + nbytes -= nblocks * bsize; + nblocks = min(nbytes / bsize, max_blks); + } while (nblocks > 0); + + err = blkcipher_walk_done(desc, &walk, nbytes); + nbytes = walk.nbytes; + if (!nbytes) + break; + + nblocks = min(nbytes / bsize, max_blks); + src = (be128 *)walk.src.virt.addr; + dst = (be128 *)walk.dst.virt.addr; + } + + return err; +} +EXPORT_SYMBOL_GPL(lrw_crypt); + static int init_tfm(struct crypto_tfm *tfm) { struct crypto_cipher *cipher; @@ -218,8 +305,9 @@ static int init_tfm(struct crypto_tfm *tfm) if (IS_ERR(cipher)) return PTR_ERR(cipher); - if (crypto_cipher_blocksize(cipher) != 16) { + if (crypto_cipher_blocksize(cipher) != LRW_BLOCK_SIZE) { *flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN; + crypto_free_cipher(cipher); return -EINVAL; } @@ -230,8 +318,8 @@ static int init_tfm(struct crypto_tfm *tfm) static void exit_tfm(struct crypto_tfm *tfm) { struct priv *ctx = crypto_tfm_ctx(tfm); - if (ctx->table) - gf128mul_free_64k(ctx->table); + + lrw_free_table(&ctx->table); crypto_free_cipher(ctx->child); }