diff options
| -rw-r--r-- | crypto/lrw.c | 507 |
1 files changed, 380 insertions, 127 deletions
diff --git a/crypto/lrw.c b/crypto/lrw.c index 6f9908a7ebcb..ecd8474018e3 100644 --- a/crypto/lrw.c +++ b/crypto/lrw.c @@ -17,7 +17,8 @@ * * The test vectors are included in the testing module tcrypt.[ch] */ -#include <crypto/algapi.h> +#include <crypto/internal/skcipher.h> +#include <crypto/scatterwalk.h> #include <linux/err.h> #include <linux/init.h> #include <linux/kernel.h> @@ -29,11 +30,30 @@ #include <crypto/gf128mul.h> #include <crypto/lrw.h> +#define LRW_BUFFER_SIZE 128u + struct priv { - struct crypto_cipher *child; + struct crypto_skcipher *child; struct lrw_table_ctx table; }; +struct rctx { + be128 buf[LRW_BUFFER_SIZE / sizeof(be128)]; + + be128 t; + + be128 *ext; + + struct scatterlist srcbuf[2]; + struct scatterlist dstbuf[2]; + struct scatterlist *src; + struct scatterlist *dst; + + unsigned int left; + + struct skcipher_request subreq; +}; + static inline void setbit128_bbe(void *b, int bit) { __set_bit(bit ^ (0x80 - @@ -76,32 +96,26 @@ void lrw_free_table(struct lrw_table_ctx *ctx) } EXPORT_SYMBOL_GPL(lrw_free_table); -static int setkey(struct crypto_tfm *parent, const u8 *key, +static int setkey(struct crypto_skcipher *parent, const u8 *key, unsigned int keylen) { - struct priv *ctx = crypto_tfm_ctx(parent); - struct crypto_cipher *child = ctx->child; + struct priv *ctx = crypto_skcipher_ctx(parent); + struct crypto_skcipher *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); + crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_skcipher_set_flags(child, crypto_skcipher_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + err = crypto_skcipher_setkey(child, key, keylen - bsize); + crypto_skcipher_set_flags(parent, crypto_skcipher_get_flags(child) & + CRYPTO_TFM_RES_MASK); 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; - struct crypto_tfm *tfm; - void (*fn)(struct crypto_tfm *, u8 *, const u8 *); -}; - static inline void inc(be128 *iv) { be64_add_cpu(&iv->b, 1); @@ -109,13 +123,6 @@ static inline void inc(be128 *iv) be64_add_cpu(&iv->a, 1); } -static inline void lrw_round(struct sinfo *s, void *dst, const void *src) -{ - be128_xor(dst, &s->t, src); /* PP <- T xor P */ - s->fn(s->tfm, dst, dst); /* CC <- E(Key2,PP) */ - be128_xor(dst, dst, &s->t); /* C <- T xor CC */ -} - /* this returns the number of consequative 1 bits starting * from the right, get_index128(00 00 00 00 00 00 ... 00 00 10 FB) = 2 */ static inline int get_index128(be128 *block) @@ -135,83 +142,263 @@ static inline int get_index128(be128 *block) return x; } -static int crypt(struct blkcipher_desc *d, - struct blkcipher_walk *w, struct priv *ctx, - void (*fn)(struct crypto_tfm *, u8 *, const u8 *)) +static int post_crypt(struct skcipher_request *req) { + struct rctx *rctx = skcipher_request_ctx(req); + be128 *buf = rctx->ext ?: rctx->buf; + struct skcipher_request *subreq; + const int bs = LRW_BLOCK_SIZE; + struct skcipher_walk w; + struct scatterlist *sg; + unsigned offset; int err; - unsigned int avail; + + subreq = &rctx->subreq; + err = skcipher_walk_virt(&w, subreq, false); + + while (w.nbytes) { + unsigned int avail = w.nbytes; + be128 *wdst; + + wdst = w.dst.virt.addr; + + do { + be128_xor(wdst, buf++, wdst); + wdst++; + } while ((avail -= bs) >= bs); + + err = skcipher_walk_done(&w, avail); + } + + rctx->left -= subreq->cryptlen; + + if (err || !rctx->left) + goto out; + + rctx->dst = rctx->dstbuf; + + scatterwalk_done(&w.out, 0, 1); + sg = w.out.sg; + offset = w.out.offset; + + if (rctx->dst != sg) { + rctx->dst[0] = *sg; + sg_unmark_end(rctx->dst); + scatterwalk_crypto_chain(rctx->dst, sg_next(sg), 0, 2); + } + rctx->dst[0].length -= offset - sg->offset; + rctx->dst[0].offset = offset; + +out: + return err; +} + +static int pre_crypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct rctx *rctx = skcipher_request_ctx(req); + struct priv *ctx = crypto_skcipher_ctx(tfm); + be128 *buf = rctx->ext ?: rctx->buf; + struct skcipher_request *subreq; const int bs = LRW_BLOCK_SIZE; - struct sinfo s = { - .tfm = crypto_cipher_tfm(ctx->child), - .fn = fn - }; + struct skcipher_walk w; + struct scatterlist *sg; + unsigned cryptlen; + unsigned offset; be128 *iv; - u8 *wsrc; - u8 *wdst; + bool more; + int err; - err = blkcipher_walk_virt(d, w); - if (!(avail = w->nbytes)) - return err; + subreq = &rctx->subreq; + skcipher_request_set_tfm(subreq, tfm); - wsrc = w->src.virt.addr; - wdst = w->dst.virt.addr; + cryptlen = subreq->cryptlen; + more = rctx->left > cryptlen; + if (!more) + cryptlen = rctx->left; - /* calculate first value of T */ - iv = (be128 *)w->iv; - s.t = *iv; + skcipher_request_set_crypt(subreq, rctx->src, rctx->dst, + cryptlen, req->iv); - /* T <- I*Key2 */ - gf128mul_64k_bbe(&s.t, ctx->table.table); + err = skcipher_walk_virt(&w, subreq, false); + iv = w.iv; - goto first; + while (w.nbytes) { + unsigned int avail = w.nbytes; + be128 *wsrc; + be128 *wdst; + + wsrc = w.src.virt.addr; + wdst = w.dst.virt.addr; - for (;;) { do { + *buf++ = rctx->t; + be128_xor(wdst++, &rctx->t, wsrc++); + /* T <- I*Key2, using the optimization * discussed in the specification */ - be128_xor(&s.t, &s.t, + be128_xor(&rctx->t, &rctx->t, &ctx->table.mulinc[get_index128(iv)]); inc(iv); + } while ((avail -= bs) >= bs); -first: - lrw_round(&s, wdst, wsrc); + err = skcipher_walk_done(&w, avail); + } - wsrc += bs; - wdst += bs; - } while ((avail -= bs) >= bs); + skcipher_request_set_tfm(subreq, ctx->child); + skcipher_request_set_crypt(subreq, rctx->dst, rctx->dst, + cryptlen, NULL); - err = blkcipher_walk_done(d, w, avail); - if (!(avail = w->nbytes)) - break; + if (err || !more) + goto out; + + rctx->src = rctx->srcbuf; + + scatterwalk_done(&w.in, 0, 1); + sg = w.in.sg; + offset = w.in.offset; + + if (rctx->src != sg) { + rctx->src[0] = *sg; + sg_unmark_end(rctx->src); + scatterwalk_crypto_chain(rctx->src, sg_next(sg), 0, 2); + } + rctx->src[0].length -= offset - sg->offset; + rctx->src[0].offset = offset; + +out: + return err; +} + +static int init_crypt(struct skcipher_request *req, crypto_completion_t done) +{ + struct priv *ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req)); + struct rctx *rctx = skcipher_request_ctx(req); + struct skcipher_request *subreq; + gfp_t gfp; + + subreq = &rctx->subreq; + skcipher_request_set_callback(subreq, req->base.flags, done, req); + + gfp = req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ? GFP_KERNEL : + GFP_ATOMIC; + rctx->ext = NULL; + + subreq->cryptlen = LRW_BUFFER_SIZE; + if (req->cryptlen > LRW_BUFFER_SIZE) { + subreq->cryptlen = min(req->cryptlen, (unsigned)PAGE_SIZE); + rctx->ext = kmalloc(subreq->cryptlen, gfp); + } + + rctx->src = req->src; + rctx->dst = req->dst; + rctx->left = req->cryptlen; + + /* calculate first value of T */ + memcpy(&rctx->t, req->iv, sizeof(rctx->t)); + + /* T <- I*Key2 */ + gf128mul_64k_bbe(&rctx->t, ctx->table.table); - wsrc = w->src.virt.addr; - wdst = w->dst.virt.addr; + return 0; +} + +static void exit_crypt(struct skcipher_request *req) +{ + struct rctx *rctx = skcipher_request_ctx(req); + + rctx->left = 0; + + if (rctx->ext) + kfree(rctx->ext); +} + +static int do_encrypt(struct skcipher_request *req, int err) +{ + struct rctx *rctx = skcipher_request_ctx(req); + struct skcipher_request *subreq; + + subreq = &rctx->subreq; + + while (!err && rctx->left) { + err = pre_crypt(req) ?: + crypto_skcipher_encrypt(subreq) ?: + post_crypt(req); + + if (err == -EINPROGRESS || + (err == -EBUSY && + req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) + return err; } + exit_crypt(req); return err; } -static int encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, - struct scatterlist *src, unsigned int nbytes) +static void encrypt_done(struct crypto_async_request *areq, int err) +{ + struct skcipher_request *req = areq->data; + struct skcipher_request *subreq; + struct rctx *rctx; + + rctx = skcipher_request_ctx(req); + subreq = &rctx->subreq; + subreq->base.flags &= CRYPTO_TFM_REQ_MAY_BACKLOG; + + err = do_encrypt(req, err ?: post_crypt(req)); + if (rctx->left) + return; + + skcipher_request_complete(req, err); +} + +static int encrypt(struct skcipher_request *req) +{ + return do_encrypt(req, init_crypt(req, encrypt_done)); +} + +static int do_decrypt(struct skcipher_request *req, int err) { - struct priv *ctx = crypto_blkcipher_ctx(desc->tfm); - struct blkcipher_walk w; + struct rctx *rctx = skcipher_request_ctx(req); + struct skcipher_request *subreq; + + subreq = &rctx->subreq; + + while (!err && rctx->left) { + err = pre_crypt(req) ?: + crypto_skcipher_decrypt(subreq) ?: + post_crypt(req); + + if (err == -EINPROGRESS || + (err == -EBUSY && + req->base.flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) + return err; + } - blkcipher_walk_init(&w, dst, src, nbytes); - return crypt(desc, &w, ctx, - crypto_cipher_alg(ctx->child)->cia_encrypt); + exit_crypt(req); + return err; } -static int decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, - struct scatterlist *src, unsigned int nbytes) +static void decrypt_done(struct crypto_async_request *areq, int err) { - struct priv *ctx = crypto_blkcipher_ctx(desc->tfm); - struct blkcipher_walk w; + struct skcipher_request *req = areq->data; + struct skcipher_request *subreq; + struct rctx *rctx; + + rctx = skcipher_request_ctx(req); + subreq = &rctx->subreq; + subreq->base.flags &= CRYPTO_TFM_REQ_MAY_BACKLOG; + + err = do_decrypt(req, err ?: post_crypt(req)); + if (rctx->left) + return; - blkcipher_walk_init(&w, dst, src, nbytes); - return crypt(desc, &w, ctx, - crypto_cipher_alg(ctx->child)->cia_decrypt); + skcipher_request_complete(req, err); +} + +static int decrypt(struct skcipher_request *req) +{ + return do_decrypt(req, init_crypt(req, decrypt_done)); } int lrw_crypt(struct blkcipher_desc *desc, struct scatterlist *sdst, @@ -293,95 +480,161 @@ first: } EXPORT_SYMBOL_GPL(lrw_crypt); -static int init_tfm(struct crypto_tfm *tfm) +static int init_tfm(struct crypto_skcipher *tfm) { - struct crypto_cipher *cipher; - struct crypto_instance *inst = (void *)tfm->__crt_alg; - struct crypto_spawn *spawn = crypto_instance_ctx(inst); - struct priv *ctx = crypto_tfm_ctx(tfm); - u32 *flags = &tfm->crt_flags; + struct skcipher_instance *inst = skcipher_alg_instance(tfm); + struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst); + struct priv *ctx = crypto_skcipher_ctx(tfm); + struct crypto_skcipher *cipher; - cipher = crypto_spawn_cipher(spawn); + cipher = crypto_spawn_skcipher(spawn); if (IS_ERR(cipher)) return PTR_ERR(cipher); - if (crypto_cipher_blocksize(cipher) != LRW_BLOCK_SIZE) { - *flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN; - crypto_free_cipher(cipher); - return -EINVAL; - } - ctx->child = cipher; + + crypto_skcipher_set_reqsize(tfm, crypto_skcipher_reqsize(cipher) + + sizeof(struct rctx)); + return 0; } -static void exit_tfm(struct crypto_tfm *tfm) +static void exit_tfm(struct crypto_skcipher *tfm) { - struct priv *ctx = crypto_tfm_ctx(tfm); + struct priv *ctx = crypto_skcipher_ctx(tfm); lrw_free_table(&ctx->table); - crypto_free_cipher(ctx->child); + crypto_free_skcipher(ctx->child); +} + +static void free(struct skcipher_instance *inst) +{ + crypto_drop_skcipher(skcipher_instance_ctx(inst)); + kfree(inst); } -static struct crypto_instance *alloc(struct rtattr **tb) +static int create(struct crypto_template *tmpl, struct rtattr **tb) { - struct crypto_instance *inst; - struct crypto_alg *alg; + struct crypto_skcipher_spawn *spawn; + struct skcipher_instance *inst; + struct crypto_attr_type *algt; + struct skcipher_alg *alg; + const char *cipher_name; + char ecb_name[CRYPTO_MAX_ALG_NAME]; int err; - err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_BLKCIPHER); + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return PTR_ERR(algt); + + if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask) + return -EINVAL; + + cipher_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(cipher_name)) + return PTR_ERR(cipher_name); + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return -ENOMEM; + + spawn = skcipher_instance_ctx(inst); + + crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst)); + err = crypto_grab_skcipher(spawn, cipher_name, 0, + crypto_requires_sync(algt->type, + algt->mask)); + if (err == -ENOENT) { + err = -ENAMETOOLONG; + if (snprintf(ecb_name, CRYPTO_MAX_ALG_NAME, "ecb(%s)", + cipher_name) >= CRYPTO_MAX_ALG_NAME) + goto err_free_inst; + + err = crypto_grab_skcipher(spawn, ecb_name, 0, + crypto_requires_sync(algt->type, + algt->mask)); + } + if (err) - return ERR_PTR(err); + goto err_free_inst; - alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER, - CRYPTO_ALG_TYPE_MASK); - if (IS_ERR(alg)) - return ERR_CAST(alg); + alg = crypto_skcipher_spawn_alg(spawn); - inst = crypto_alloc_instance("lrw", alg); - if (IS_ERR(inst)) - goto out_put_alg; + err = -EINVAL; + if (alg->base.cra_blocksize != LRW_BLOCK_SIZE) + goto err_drop_spawn; - inst->alg.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER; - inst->alg.cra_priority = alg->cra_priority; - inst->alg.cra_blocksize = alg->cra_blocksize; + if (crypto_skcipher_alg_ivsize(alg)) + goto err_drop_spawn; - if (alg->cra_alignmask < 7) inst->alg.cra_alignmask = 7; - else inst->alg.cra_alignmask = alg->cra_alignmask; - inst->alg.cra_type = &crypto_blkcipher_type; + err = crypto_inst_setname(skcipher_crypto_instance(inst), "lrw", + &alg->base); + if (err) + goto err_drop_spawn; - if (!(alg->cra_blocksize % 4)) - inst->alg.cra_alignmask |= 3; - inst->alg.cra_blkcipher.ivsize = alg->cra_blocksize; - inst->alg.cra_blkcipher.min_keysize = - alg->cra_cipher.cia_min_keysize + alg->cra_blocksize; - inst->alg.cra_blkcipher.max_keysize = - alg->cra_cipher.cia_max_keysize + alg->cra_blocksize; + err = -EINVAL; + cipher_name = alg->base.cra_name; - inst->alg.cra_ctxsize = sizeof(struct priv); + /* Alas we screwed up the naming so we have to mangle the + * cipher name. + */ + if (!strncmp(cipher_name, "ecb(", 4)) { + unsigned len; - inst->alg.cra_init = init_tfm; - inst->alg.cra_exit = exit_tfm; + len = strlcpy(ecb_name, cipher_name + 4, sizeof(ecb_name)); + if (len < 2 || len >= sizeof(ecb_name)) + goto err_drop_spawn; - inst->alg.cra_blkcipher.setkey = setkey; - inst->alg.cra_blkcipher.encrypt = encrypt; - inst->alg.cra_blkcipher.decrypt = decrypt; + if (ecb_name[len - 1] != ')') + goto err_drop_spawn; -out_put_alg: - crypto_mod_put(alg); - return inst; -} + ecb_name[len - 1] = 0; -static void free(struct crypto_instance *inst) -{ - crypto_drop_spawn(crypto_instance_ctx(inst)); + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, + "lrw(%s)", ecb_name) >= CRYPTO_MAX_ALG_NAME) + return -ENAMETOOLONG; + } + + inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.base.cra_priority = alg->base.cra_priority; + inst->alg.base.cra_blocksize = LRW_BLOCK_SIZE; + inst->alg.base.cra_alignmask = alg->base.cra_alignmask | + (__alignof__(u64) - 1); + + inst->alg.ivsize = LRW_BLOCK_SIZE; + inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg) + + LRW_BLOCK_SIZE; + inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg) + + LRW_BLOCK_SIZE; + + inst->alg.base.cra_ctxsize = sizeof(struct priv); + + inst->alg.init = init_tfm; + inst->alg.exit = exit_tfm; + + inst->alg.setkey = setkey; + inst->alg.encrypt = encrypt; + inst->alg.decrypt = decrypt; + + inst->free = free; + + err = skcipher_register_instance(tmpl, inst); + if (err) + goto err_drop_spawn; + +out: + return err; + +err_drop_spawn: + crypto_drop_skcipher(spawn); +err_free_inst: kfree(inst); + goto out; } static struct crypto_template crypto_tmpl = { .name = "lrw", - .alloc = alloc, - .free = free, + .create = create, .module = THIS_MODULE, }; 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