diff options
Diffstat (limited to 'crypto/gcm.c')
| -rw-r--r-- | crypto/gcm.c | 1447 |
1 files changed, 1447 insertions, 0 deletions
diff --git a/crypto/gcm.c b/crypto/gcm.c new file mode 100644 index 000000000..2e403f613 --- /dev/null +++ b/crypto/gcm.c @@ -0,0 +1,1447 @@ +/* + * GCM: Galois/Counter Mode. + * + * Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#include <crypto/gf128mul.h> +#include <crypto/internal/aead.h> +#include <crypto/internal/skcipher.h> +#include <crypto/internal/hash.h> +#include <crypto/scatterwalk.h> +#include <crypto/hash.h> +#include "internal.h" +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> + +struct gcm_instance_ctx { + struct crypto_skcipher_spawn ctr; + struct crypto_ahash_spawn ghash; +}; + +struct crypto_gcm_ctx { + struct crypto_ablkcipher *ctr; + struct crypto_ahash *ghash; +}; + +struct crypto_rfc4106_ctx { + struct crypto_aead *child; + u8 nonce[4]; +}; + +struct crypto_rfc4543_instance_ctx { + struct crypto_aead_spawn aead; + struct crypto_skcipher_spawn null; +}; + +struct crypto_rfc4543_ctx { + struct crypto_aead *child; + struct crypto_blkcipher *null; + u8 nonce[4]; +}; + +struct crypto_rfc4543_req_ctx { + u8 auth_tag[16]; + u8 assocbuf[32]; + struct scatterlist cipher[1]; + struct scatterlist payload[2]; + struct scatterlist assoc[2]; + struct aead_request subreq; +}; + +struct crypto_gcm_ghash_ctx { + unsigned int cryptlen; + struct scatterlist *src; + void (*complete)(struct aead_request *req, int err); +}; + +struct crypto_gcm_req_priv_ctx { + u8 auth_tag[16]; + u8 iauth_tag[16]; + struct scatterlist src[2]; + struct scatterlist dst[2]; + struct crypto_gcm_ghash_ctx ghash_ctx; + union { + struct ahash_request ahreq; + struct ablkcipher_request abreq; + } u; +}; + +struct crypto_gcm_setkey_result { + int err; + struct completion completion; +}; + +static void *gcm_zeroes; + +static inline struct crypto_gcm_req_priv_ctx *crypto_gcm_reqctx( + struct aead_request *req) +{ + unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req)); + + return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1); +} + +static void crypto_gcm_setkey_done(struct crypto_async_request *req, int err) +{ + struct crypto_gcm_setkey_result *result = req->data; + + if (err == -EINPROGRESS) + return; + + result->err = err; + complete(&result->completion); +} + +static int crypto_gcm_setkey(struct crypto_aead *aead, const u8 *key, + unsigned int keylen) +{ + struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_ahash *ghash = ctx->ghash; + struct crypto_ablkcipher *ctr = ctx->ctr; + struct { + be128 hash; + u8 iv[8]; + + struct crypto_gcm_setkey_result result; + + struct scatterlist sg[1]; + struct ablkcipher_request req; + } *data; + int err; + + crypto_ablkcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK); + crypto_ablkcipher_set_flags(ctr, crypto_aead_get_flags(aead) & + CRYPTO_TFM_REQ_MASK); + + err = crypto_ablkcipher_setkey(ctr, key, keylen); + if (err) + return err; + + crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctr) & + CRYPTO_TFM_RES_MASK); + + data = kzalloc(sizeof(*data) + crypto_ablkcipher_reqsize(ctr), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + init_completion(&data->result.completion); + sg_init_one(data->sg, &data->hash, sizeof(data->hash)); + ablkcipher_request_set_tfm(&data->req, ctr); + ablkcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP | + CRYPTO_TFM_REQ_MAY_BACKLOG, + crypto_gcm_setkey_done, + &data->result); + ablkcipher_request_set_crypt(&data->req, data->sg, data->sg, + sizeof(data->hash), data->iv); + + err = crypto_ablkcipher_encrypt(&data->req); + if (err == -EINPROGRESS || err == -EBUSY) { + err = wait_for_completion_interruptible( + &data->result.completion); + if (!err) + err = data->result.err; + } + + if (err) + goto out; + + crypto_ahash_clear_flags(ghash, CRYPTO_TFM_REQ_MASK); + crypto_ahash_set_flags(ghash, crypto_aead_get_flags(aead) & + CRYPTO_TFM_REQ_MASK); + err = crypto_ahash_setkey(ghash, (u8 *)&data->hash, sizeof(be128)); + crypto_aead_set_flags(aead, crypto_ahash_get_flags(ghash) & + CRYPTO_TFM_RES_MASK); + +out: + kfree(data); + return err; +} + +static int crypto_gcm_setauthsize(struct crypto_aead *tfm, + unsigned int authsize) +{ + switch (authsize) { + case 4: + case 8: + case 12: + case 13: + case 14: + case 15: + case 16: + break; + default: + return -EINVAL; + } + + return 0; +} + +static void crypto_gcm_init_crypt(struct ablkcipher_request *ablk_req, + struct aead_request *req, + unsigned int cryptlen) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_gcm_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct scatterlist *dst; + __be32 counter = cpu_to_be32(1); + + memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag)); + memcpy(req->iv + 12, &counter, 4); + + sg_init_table(pctx->src, 2); + sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag)); + scatterwalk_sg_chain(pctx->src, 2, req->src); + + dst = pctx->src; + if (req->src != req->dst) { + sg_init_table(pctx->dst, 2); + sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag)); + scatterwalk_sg_chain(pctx->dst, 2, req->dst); + dst = pctx->dst; + } + + ablkcipher_request_set_tfm(ablk_req, ctx->ctr); + ablkcipher_request_set_crypt(ablk_req, pctx->src, dst, + cryptlen + sizeof(pctx->auth_tag), + req->iv); +} + +static inline unsigned int gcm_remain(unsigned int len) +{ + len &= 0xfU; + return len ? 16 - len : 0; +} + +static void gcm_hash_len_done(struct crypto_async_request *areq, int err); +static void gcm_hash_final_done(struct crypto_async_request *areq, int err); + +static int gcm_hash_update(struct aead_request *req, + struct crypto_gcm_req_priv_ctx *pctx, + crypto_completion_t compl, + struct scatterlist *src, + unsigned int len) +{ + struct ahash_request *ahreq = &pctx->u.ahreq; + + ahash_request_set_callback(ahreq, aead_request_flags(req), + compl, req); + ahash_request_set_crypt(ahreq, src, NULL, len); + + return crypto_ahash_update(ahreq); +} + +static int gcm_hash_remain(struct aead_request *req, + struct crypto_gcm_req_priv_ctx *pctx, + unsigned int remain, + crypto_completion_t compl) +{ + struct ahash_request *ahreq = &pctx->u.ahreq; + + ahash_request_set_callback(ahreq, aead_request_flags(req), + compl, req); + sg_init_one(pctx->src, gcm_zeroes, remain); + ahash_request_set_crypt(ahreq, pctx->src, NULL, remain); + + return crypto_ahash_update(ahreq); +} + +static int gcm_hash_len(struct aead_request *req, + struct crypto_gcm_req_priv_ctx *pctx) +{ + struct ahash_request *ahreq = &pctx->u.ahreq; + struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; + u128 lengths; + + lengths.a = cpu_to_be64(req->assoclen * 8); + lengths.b = cpu_to_be64(gctx->cryptlen * 8); + memcpy(pctx->iauth_tag, &lengths, 16); + sg_init_one(pctx->src, pctx->iauth_tag, 16); + ahash_request_set_callback(ahreq, aead_request_flags(req), + gcm_hash_len_done, req); + ahash_request_set_crypt(ahreq, pctx->src, + NULL, sizeof(lengths)); + + return crypto_ahash_update(ahreq); +} + +static int gcm_hash_final(struct aead_request *req, + struct crypto_gcm_req_priv_ctx *pctx) +{ + struct ahash_request *ahreq = &pctx->u.ahreq; + + ahash_request_set_callback(ahreq, aead_request_flags(req), + gcm_hash_final_done, req); + ahash_request_set_crypt(ahreq, NULL, pctx->iauth_tag, 0); + + return crypto_ahash_final(ahreq); +} + +static void __gcm_hash_final_done(struct aead_request *req, int err) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; + + if (!err) + crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16); + + gctx->complete(req, err); +} + +static void gcm_hash_final_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + + __gcm_hash_final_done(req, err); +} + +static void __gcm_hash_len_done(struct aead_request *req, int err) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + + if (!err) { + err = gcm_hash_final(req, pctx); + if (err == -EINPROGRESS || err == -EBUSY) + return; + } + + __gcm_hash_final_done(req, err); +} + +static void gcm_hash_len_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + + __gcm_hash_len_done(req, err); +} + +static void __gcm_hash_crypt_remain_done(struct aead_request *req, int err) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + + if (!err) { + err = gcm_hash_len(req, pctx); + if (err == -EINPROGRESS || err == -EBUSY) + return; + } + + __gcm_hash_len_done(req, err); +} + +static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq, + int err) +{ + struct aead_request *req = areq->data; + + __gcm_hash_crypt_remain_done(req, err); +} + +static void __gcm_hash_crypt_done(struct aead_request *req, int err) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; + unsigned int remain; + + if (!err) { + remain = gcm_remain(gctx->cryptlen); + BUG_ON(!remain); + err = gcm_hash_remain(req, pctx, remain, + gcm_hash_crypt_remain_done); + if (err == -EINPROGRESS || err == -EBUSY) + return; + } + + __gcm_hash_crypt_remain_done(req, err); +} + +static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + + __gcm_hash_crypt_done(req, err); +} + +static void __gcm_hash_assoc_remain_done(struct aead_request *req, int err) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; + crypto_completion_t compl; + unsigned int remain = 0; + + if (!err && gctx->cryptlen) { + remain = gcm_remain(gctx->cryptlen); + compl = remain ? gcm_hash_crypt_done : + gcm_hash_crypt_remain_done; + err = gcm_hash_update(req, pctx, compl, + gctx->src, gctx->cryptlen); + if (err == -EINPROGRESS || err == -EBUSY) + return; + } + + if (remain) + __gcm_hash_crypt_done(req, err); + else + __gcm_hash_crypt_remain_done(req, err); +} + +static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq, + int err) +{ + struct aead_request *req = areq->data; + + __gcm_hash_assoc_remain_done(req, err); +} + +static void __gcm_hash_assoc_done(struct aead_request *req, int err) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + unsigned int remain; + + if (!err) { + remain = gcm_remain(req->assoclen); + BUG_ON(!remain); + err = gcm_hash_remain(req, pctx, remain, + gcm_hash_assoc_remain_done); + if (err == -EINPROGRESS || err == -EBUSY) + return; + } + + __gcm_hash_assoc_remain_done(req, err); +} + +static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + + __gcm_hash_assoc_done(req, err); +} + +static void __gcm_hash_init_done(struct aead_request *req, int err) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + crypto_completion_t compl; + unsigned int remain = 0; + + if (!err && req->assoclen) { + remain = gcm_remain(req->assoclen); + compl = remain ? gcm_hash_assoc_done : + gcm_hash_assoc_remain_done; + err = gcm_hash_update(req, pctx, compl, + req->assoc, req->assoclen); + if (err == -EINPROGRESS || err == -EBUSY) + return; + } + + if (remain) + __gcm_hash_assoc_done(req, err); + else + __gcm_hash_assoc_remain_done(req, err); +} + +static void gcm_hash_init_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + + __gcm_hash_init_done(req, err); +} + +static int gcm_hash(struct aead_request *req, + struct crypto_gcm_req_priv_ctx *pctx) +{ + struct ahash_request *ahreq = &pctx->u.ahreq; + struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; + struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(req->base.tfm); + unsigned int remain; + crypto_completion_t compl; + int err; + + ahash_request_set_tfm(ahreq, ctx->ghash); + + ahash_request_set_callback(ahreq, aead_request_flags(req), + gcm_hash_init_done, req); + err = crypto_ahash_init(ahreq); + if (err) + return err; + remain = gcm_remain(req->assoclen); + compl = remain ? gcm_hash_assoc_done : gcm_hash_assoc_remain_done; + err = gcm_hash_update(req, pctx, compl, req->assoc, req->assoclen); + if (err) + return err; + if (remain) { + err = gcm_hash_remain(req, pctx, remain, + gcm_hash_assoc_remain_done); + if (err) + return err; + } + remain = gcm_remain(gctx->cryptlen); + compl = remain ? gcm_hash_crypt_done : gcm_hash_crypt_remain_done; + err = gcm_hash_update(req, pctx, compl, gctx->src, gctx->cryptlen); + if (err) + return err; + if (remain) { + err = gcm_hash_remain(req, pctx, remain, + gcm_hash_crypt_remain_done); + if (err) + return err; + } + err = gcm_hash_len(req, pctx); + if (err) + return err; + err = gcm_hash_final(req, pctx); + if (err) + return err; + + return 0; +} + +static void gcm_enc_copy_hash(struct aead_request *req, + struct crypto_gcm_req_priv_ctx *pctx) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + u8 *auth_tag = pctx->auth_tag; + + scatterwalk_map_and_copy(auth_tag, req->dst, req->cryptlen, + crypto_aead_authsize(aead), 1); +} + +static void gcm_enc_hash_done(struct aead_request *req, int err) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + + if (!err) + gcm_enc_copy_hash(req, pctx); + + aead_request_complete(req, err); +} + +static void gcm_encrypt_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + + if (!err) { + err = gcm_hash(req, pctx); + if (err == -EINPROGRESS || err == -EBUSY) + return; + else if (!err) { + crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16); + gcm_enc_copy_hash(req, pctx); + } + } + + aead_request_complete(req, err); +} + +static int crypto_gcm_encrypt(struct aead_request *req) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct ablkcipher_request *abreq = &pctx->u.abreq; + struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; + int err; + + crypto_gcm_init_crypt(abreq, req, req->cryptlen); + ablkcipher_request_set_callback(abreq, aead_request_flags(req), + gcm_encrypt_done, req); + + gctx->src = req->dst; + gctx->cryptlen = req->cryptlen; + gctx->complete = gcm_enc_hash_done; + + err = crypto_ablkcipher_encrypt(abreq); + if (err) + return err; + + err = gcm_hash(req, pctx); + if (err) + return err; + + crypto_xor(pctx->auth_tag, pctx->iauth_tag, 16); + gcm_enc_copy_hash(req, pctx); + + return 0; +} + +static int crypto_gcm_verify(struct aead_request *req, + struct crypto_gcm_req_priv_ctx *pctx) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + u8 *auth_tag = pctx->auth_tag; + u8 *iauth_tag = pctx->iauth_tag; + unsigned int authsize = crypto_aead_authsize(aead); + unsigned int cryptlen = req->cryptlen - authsize; + + crypto_xor(auth_tag, iauth_tag, 16); + scatterwalk_map_and_copy(iauth_tag, req->src, cryptlen, authsize, 0); + return crypto_memneq(iauth_tag, auth_tag, authsize) ? -EBADMSG : 0; +} + +static void gcm_decrypt_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + + if (!err) + err = crypto_gcm_verify(req, pctx); + + aead_request_complete(req, err); +} + +static void gcm_dec_hash_done(struct aead_request *req, int err) +{ + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct ablkcipher_request *abreq = &pctx->u.abreq; + struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; + + if (!err) { + ablkcipher_request_set_callback(abreq, aead_request_flags(req), + gcm_decrypt_done, req); + crypto_gcm_init_crypt(abreq, req, gctx->cryptlen); + err = crypto_ablkcipher_decrypt(abreq); + if (err == -EINPROGRESS || err == -EBUSY) + return; + else if (!err) + err = crypto_gcm_verify(req, pctx); + } + + aead_request_complete(req, err); +} + +static int crypto_gcm_decrypt(struct aead_request *req) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); + struct ablkcipher_request *abreq = &pctx->u.abreq; + struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; + unsigned int authsize = crypto_aead_authsize(aead); + unsigned int cryptlen = req->cryptlen; + int err; + + if (cryptlen < authsize) + return -EINVAL; + cryptlen -= authsize; + + gctx->src = req->src; + gctx->cryptlen = cryptlen; + gctx->complete = gcm_dec_hash_done; + + err = gcm_hash(req, pctx); + if (err) + return err; + + ablkcipher_request_set_callback(abreq, aead_request_flags(req), + gcm_decrypt_done, req); + crypto_gcm_init_crypt(abreq, req, cryptlen); + err = crypto_ablkcipher_decrypt(abreq); + if (err) + return err; + + return crypto_gcm_verify(req, pctx); +} + +static int crypto_gcm_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_instance *inst = (void *)tfm->__crt_alg; + struct gcm_instance_ctx *ictx = crypto_instance_ctx(inst); + struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm); + struct crypto_ablkcipher *ctr; + struct crypto_ahash *ghash; + unsigned long align; + int err; + + ghash = crypto_spawn_ahash(&ictx->ghash); + if (IS_ERR(ghash)) + return PTR_ERR(ghash); + + ctr = crypto_spawn_skcipher(&ictx->ctr); + err = PTR_ERR(ctr); + if (IS_ERR(ctr)) + goto err_free_hash; + + ctx->ctr = ctr; + ctx->ghash = ghash; + + align = crypto_tfm_alg_alignmask(tfm); + align &= ~(crypto_tfm_ctx_alignment() - 1); + tfm->crt_aead.reqsize = align + + offsetof(struct crypto_gcm_req_priv_ctx, u) + + max(sizeof(struct ablkcipher_request) + + crypto_ablkcipher_reqsize(ctr), + sizeof(struct ahash_request) + + crypto_ahash_reqsize(ghash)); + + return 0; + +err_free_hash: + crypto_free_ahash(ghash); + return err; +} + +static void crypto_gcm_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_gcm_ctx *ctx = crypto_tfm_ctx(tfm); + + crypto_free_ahash(ctx->ghash); + crypto_free_ablkcipher(ctx->ctr); +} + +static struct crypto_instance *crypto_gcm_alloc_common(struct rtattr **tb, + const char *full_name, + const char *ctr_name, + const char *ghash_name) +{ + struct crypto_attr_type *algt; + struct crypto_instance *inst; + struct crypto_alg *ctr; + struct crypto_alg *ghash_alg; + struct ahash_alg *ghash_ahash_alg; + struct gcm_instance_ctx *ctx; + int err; + + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return ERR_CAST(algt); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return ERR_PTR(-EINVAL); + + ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type, + CRYPTO_ALG_TYPE_HASH, + CRYPTO_ALG_TYPE_AHASH_MASK); + if (IS_ERR(ghash_alg)) + return ERR_CAST(ghash_alg); + + err = -ENOMEM; + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + if (!inst) + goto out_put_ghash; + + ctx = crypto_instance_ctx(inst); + ghash_ahash_alg = container_of(ghash_alg, struct ahash_alg, halg.base); + err = crypto_init_ahash_spawn(&ctx->ghash, &ghash_ahash_alg->halg, + inst); + if (err) + goto err_free_inst; + + crypto_set_skcipher_spawn(&ctx->ctr, inst); + err = crypto_grab_skcipher(&ctx->ctr, ctr_name, 0, + crypto_requires_sync(algt->type, + algt->mask)); + if (err) + goto err_drop_ghash; + + ctr = crypto_skcipher_spawn_alg(&ctx->ctr); + + /* We only support 16-byte blocks. */ + if (ctr->cra_ablkcipher.ivsize != 16) + goto out_put_ctr; + + /* Not a stream cipher? */ + err = -EINVAL; + if (ctr->cra_blocksize != 1) + goto out_put_ctr; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "gcm_base(%s,%s)", ctr->cra_driver_name, + ghash_alg->cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) + goto out_put_ctr; + + memcpy(inst->alg.cra_name, full_name, CRYPTO_MAX_ALG_NAME); + + inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD; + inst->alg.cra_flags |= ctr->cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.cra_priority = ctr->cra_priority; + inst->alg.cra_blocksize = 1; + inst->alg.cra_alignmask = ctr->cra_alignmask | (__alignof__(u64) - 1); + inst->alg.cra_type = &crypto_aead_type; + inst->alg.cra_aead.ivsize = 16; + inst->alg.cra_aead.maxauthsize = 16; + inst->alg.cra_ctxsize = sizeof(struct crypto_gcm_ctx); + inst->alg.cra_init = crypto_gcm_init_tfm; + inst->alg.cra_exit = crypto_gcm_exit_tfm; + inst->alg.cra_aead.setkey = crypto_gcm_setkey; + inst->alg.cra_aead.setauthsize = crypto_gcm_setauthsize; + inst->alg.cra_aead.encrypt = crypto_gcm_encrypt; + inst->alg.cra_aead.decrypt = crypto_gcm_decrypt; + +out: + crypto_mod_put(ghash_alg); + return inst; + +out_put_ctr: + crypto_drop_skcipher(&ctx->ctr); +err_drop_ghash: + crypto_drop_ahash(&ctx->ghash); +err_free_inst: + kfree(inst); +out_put_ghash: + inst = ERR_PTR(err); + goto out; +} + +static struct crypto_instance *crypto_gcm_alloc(struct rtattr **tb) +{ + const char *cipher_name; + char ctr_name[CRYPTO_MAX_ALG_NAME]; + char full_name[CRYPTO_MAX_ALG_NAME]; + + cipher_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(cipher_name)) + return ERR_CAST(cipher_name); + + if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >= + CRYPTO_MAX_ALG_NAME) + return ERR_PTR(-ENAMETOOLONG); + + if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm(%s)", cipher_name) >= + CRYPTO_MAX_ALG_NAME) + return ERR_PTR(-ENAMETOOLONG); + + return crypto_gcm_alloc_common(tb, full_name, ctr_name, "ghash"); +} + +static void crypto_gcm_free(struct crypto_instance *inst) +{ + struct gcm_instance_ctx *ctx = crypto_instance_ctx(inst); + + crypto_drop_skcipher(&ctx->ctr); + crypto_drop_ahash(&ctx->ghash); + kfree(inst); +} + +static struct crypto_template crypto_gcm_tmpl = { + .name = "gcm", + .alloc = crypto_gcm_alloc, + .free = crypto_gcm_free, + .module = THIS_MODULE, +}; + +static struct crypto_instance *crypto_gcm_base_alloc(struct rtattr **tb) +{ + const char *ctr_name; + const char *ghash_name; + char full_name[CRYPTO_MAX_ALG_NAME]; + + ctr_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(ctr_name)) + return ERR_CAST(ctr_name); + + ghash_name = crypto_attr_alg_name(tb[2]); + if (IS_ERR(ghash_name)) + return ERR_CAST(ghash_name); + + if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)", + ctr_name, ghash_name) >= CRYPTO_MAX_ALG_NAME) + return ERR_PTR(-ENAMETOOLONG); + + return crypto_gcm_alloc_common(tb, full_name, ctr_name, ghash_name); +} + +static struct crypto_template crypto_gcm_base_tmpl = { + .name = "gcm_base", + .alloc = crypto_gcm_base_alloc, + .free = crypto_gcm_free, + .module = THIS_MODULE, +}; + +static int crypto_rfc4106_setkey(struct crypto_aead *parent, const u8 *key, + unsigned int keylen) +{ + struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent); + struct crypto_aead *child = ctx->child; + int err; + + if (keylen < 4) + return -EINVAL; + + keylen -= 4; + memcpy(ctx->nonce, key + keylen, 4); + + crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_aead_set_flags(child, crypto_aead_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + err = crypto_aead_setkey(child, key, keylen); + crypto_aead_set_flags(parent, crypto_aead_get_flags(child) & + CRYPTO_TFM_RES_MASK); + + return err; +} + +static int crypto_rfc4106_setauthsize(struct crypto_aead *parent, + unsigned int authsize) +{ + struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(parent); + + switch (authsize) { + case 8: + case 12: + case 16: + break; + default: + return -EINVAL; + } + + return crypto_aead_setauthsize(ctx->child, authsize); +} + +static struct aead_request *crypto_rfc4106_crypt(struct aead_request *req) +{ + struct aead_request *subreq = aead_request_ctx(req); + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_aead *child = ctx->child; + u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child), + crypto_aead_alignmask(child) + 1); + + memcpy(iv, ctx->nonce, 4); + memcpy(iv + 4, req->iv, 8); + + aead_request_set_tfm(subreq, child); + aead_request_set_callback(subreq, req->base.flags, req->base.complete, + req->base.data); + aead_request_set_crypt(subreq, req->src, req->dst, req->cryptlen, iv); + aead_request_set_assoc(subreq, req->assoc, req->assoclen); + + return subreq; +} + +static int crypto_rfc4106_encrypt(struct aead_request *req) +{ + req = crypto_rfc4106_crypt(req); + + return crypto_aead_encrypt(req); +} + +static int crypto_rfc4106_decrypt(struct aead_request *req) +{ + req = crypto_rfc4106_crypt(req); + + return crypto_aead_decrypt(req); +} + +static int crypto_rfc4106_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_instance *inst = (void *)tfm->__crt_alg; + struct crypto_aead_spawn *spawn = crypto_instance_ctx(inst); + struct crypto_rfc4106_ctx *ctx = crypto_tfm_ctx(tfm); + struct crypto_aead *aead; + unsigned long align; + + aead = crypto_spawn_aead(spawn); + if (IS_ERR(aead)) + return PTR_ERR(aead); + + ctx->child = aead; + + align = crypto_aead_alignmask(aead); + align &= ~(crypto_tfm_ctx_alignment() - 1); + tfm->crt_aead.reqsize = sizeof(struct aead_request) + + ALIGN(crypto_aead_reqsize(aead), + crypto_tfm_ctx_alignment()) + + align + 16; + + return 0; +} + +static void crypto_rfc4106_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_rfc4106_ctx *ctx = crypto_tfm_ctx(tfm); + + crypto_free_aead(ctx->child); +} + +static struct crypto_instance *crypto_rfc4106_alloc(struct rtattr **tb) +{ + struct crypto_attr_type *algt; + struct crypto_instance *inst; + struct crypto_aead_spawn *spawn; + struct crypto_alg *alg; + const char *ccm_name; + int err; + + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return ERR_CAST(algt); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return ERR_PTR(-EINVAL); + + ccm_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(ccm_name)) + return ERR_CAST(ccm_name); + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return ERR_PTR(-ENOMEM); + + spawn = crypto_instance_ctx(inst); + crypto_set_aead_spawn(spawn, inst); + err = crypto_grab_aead(spawn, ccm_name, 0, + crypto_requires_sync(algt->type, algt->mask)); + if (err) + goto out_free_inst; + + alg = crypto_aead_spawn_alg(spawn); + + err = -EINVAL; + + /* We only support 16-byte blocks. */ + if (alg->cra_aead.ivsize != 16) + goto out_drop_alg; + + /* Not a stream cipher? */ + if (alg->cra_blocksize != 1) + goto out_drop_alg; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, + "rfc4106(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME || + snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "rfc4106(%s)", alg->cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) + goto out_drop_alg; + + inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD; + inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.cra_priority = alg->cra_priority; + inst->alg.cra_blocksize = 1; + inst->alg.cra_alignmask = alg->cra_alignmask; + inst->alg.cra_type = &crypto_nivaead_type; + + inst->alg.cra_aead.ivsize = 8; + inst->alg.cra_aead.maxauthsize = 16; + + inst->alg.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx); + + inst->alg.cra_init = crypto_rfc4106_init_tfm; + inst->alg.cra_exit = crypto_rfc4106_exit_tfm; + + inst->alg.cra_aead.setkey = crypto_rfc4106_setkey; + inst->alg.cra_aead.setauthsize = crypto_rfc4106_setauthsize; + inst->alg.cra_aead.encrypt = crypto_rfc4106_encrypt; + inst->alg.cra_aead.decrypt = crypto_rfc4106_decrypt; + + inst->alg.cra_aead.geniv = "seqiv"; + +out: + return inst; + +out_drop_alg: + crypto_drop_aead(spawn); +out_free_inst: + kfree(inst); + inst = ERR_PTR(err); + goto out; +} + +static void crypto_rfc4106_free(struct crypto_instance *inst) +{ + crypto_drop_spawn(crypto_instance_ctx(inst)); + kfree(inst); +} + +static struct crypto_template crypto_rfc4106_tmpl = { + .name = "rfc4106", + .alloc = crypto_rfc4106_alloc, + .free = crypto_rfc4106_free, + .module = THIS_MODULE, +}; + +static inline struct crypto_rfc4543_req_ctx *crypto_rfc4543_reqctx( + struct aead_request *req) +{ + unsigned long align = crypto_aead_alignmask(crypto_aead_reqtfm(req)); + + return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), align + 1); +} + +static int crypto_rfc4543_setkey(struct crypto_aead *parent, const u8 *key, + unsigned int keylen) +{ + struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent); + struct crypto_aead *child = ctx->child; + int err; + + if (keylen < 4) + return -EINVAL; + + keylen -= 4; + memcpy(ctx->nonce, key + keylen, 4); + + crypto_aead_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_aead_set_flags(child, crypto_aead_get_flags(parent) & + CRYPTO_TFM_REQ_MASK); + err = crypto_aead_setkey(child, key, keylen); + crypto_aead_set_flags(parent, crypto_aead_get_flags(child) & + CRYPTO_TFM_RES_MASK); + + return err; +} + +static int crypto_rfc4543_setauthsize(struct crypto_aead *parent, + unsigned int authsize) +{ + struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(parent); + + if (authsize != 16) + return -EINVAL; + + return crypto_aead_setauthsize(ctx->child, authsize); +} + +static void crypto_rfc4543_done(struct crypto_async_request *areq, int err) +{ + struct aead_request *req = areq->data; + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req); + + if (!err) { + scatterwalk_map_and_copy(rctx->auth_tag, req->dst, + req->cryptlen, + crypto_aead_authsize(aead), 1); + } + + aead_request_complete(req, err); +} + +static struct aead_request *crypto_rfc4543_crypt(struct aead_request *req, + bool enc) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead); + struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req); + struct aead_request *subreq = &rctx->subreq; + struct scatterlist *src = req->src; + struct scatterlist *cipher = rctx->cipher; + struct scatterlist *payload = rctx->payload; + struct scatterlist *assoc = rctx->assoc; + unsigned int authsize = crypto_aead_authsize(aead); + unsigned int assoclen = req->assoclen; + struct page *srcp; + u8 *vsrc; + u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child), + crypto_aead_alignmask(ctx->child) + 1); + + memcpy(iv, ctx->nonce, 4); + memcpy(iv + 4, req->iv, 8); + + /* construct cipher/plaintext */ + if (enc) + memset(rctx->auth_tag, 0, authsize); + else + scatterwalk_map_and_copy(rctx->auth_tag, src, + req->cryptlen - authsize, + authsize, 0); + + sg_init_one(cipher, rctx->auth_tag, authsize); + + /* construct the aad */ + srcp = sg_page(src); + vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset; + + sg_init_table(payload, 2); + sg_set_buf(payload, req->iv, 8); + scatterwalk_crypto_chain(payload, src, vsrc == req->iv + 8, 2); + assoclen += 8 + req->cryptlen - (enc ? 0 : authsize); + + if (req->assoc->length == req->assoclen) { + sg_init_table(assoc, 2); + sg_set_page(assoc, sg_page(req->assoc), req->assoc->length, + req->assoc->offset); + } else { + BUG_ON(req->assoclen > sizeof(rctx->assocbuf)); + + scatterwalk_map_and_copy(rctx->assocbuf, req->assoc, 0, + req->assoclen, 0); + + sg_init_table(assoc, 2); + sg_set_buf(assoc, rctx->assocbuf, req->assoclen); + } + scatterwalk_crypto_chain(assoc, payload, 0, 2); + + aead_request_set_tfm(subreq, ctx->child); + aead_request_set_callback(subreq, req->base.flags, crypto_rfc4543_done, + req); + aead_request_set_crypt(subreq, cipher, cipher, enc ? 0 : authsize, iv); + aead_request_set_assoc(subreq, assoc, assoclen); + + return subreq; +} + +static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead); + unsigned int authsize = crypto_aead_authsize(aead); + unsigned int nbytes = req->cryptlen - (enc ? 0 : authsize); + struct blkcipher_desc desc = { + .tfm = ctx->null, + }; + + return crypto_blkcipher_encrypt(&desc, req->dst, req->src, nbytes); +} + +static int crypto_rfc4543_encrypt(struct aead_request *req) +{ + struct crypto_aead *aead = crypto_aead_reqtfm(req); + struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req); + struct aead_request *subreq; + int err; + + if (req->src != req->dst) { + err = crypto_rfc4543_copy_src_to_dst(req, true); + if (err) + return err; + } + + subreq = crypto_rfc4543_crypt(req, true); + err = crypto_aead_encrypt(subreq); + if (err) + return err; + + scatterwalk_map_and_copy(rctx->auth_tag, req->dst, req->cryptlen, + crypto_aead_authsize(aead), 1); + + return 0; +} + +static int crypto_rfc4543_decrypt(struct aead_request *req) +{ + int err; + + if (req->src != req->dst) { + err = crypto_rfc4543_copy_src_to_dst(req, false); + if (err) + return err; + } + + req = crypto_rfc4543_crypt(req, false); + + return crypto_aead_decrypt(req); +} + +static int crypto_rfc4543_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_instance *inst = (void *)tfm->__crt_alg; + struct crypto_rfc4543_instance_ctx *ictx = crypto_instance_ctx(inst); + struct crypto_aead_spawn *spawn = &ictx->aead; + struct crypto_rfc4543_ctx *ctx = crypto_tfm_ctx(tfm); + struct crypto_aead *aead; + struct crypto_blkcipher *null; + unsigned long align; + int err = 0; + + aead = crypto_spawn_aead(spawn); + if (IS_ERR(aead)) + return PTR_ERR(aead); + + null = crypto_spawn_blkcipher(&ictx->null.base); + err = PTR_ERR(null); + if (IS_ERR(null)) + goto err_free_aead; + + ctx->child = aead; + ctx->null = null; + + align = crypto_aead_alignmask(aead); + align &= ~(crypto_tfm_ctx_alignment() - 1); + tfm->crt_aead.reqsize = sizeof(struct crypto_rfc4543_req_ctx) + + ALIGN(crypto_aead_reqsize(aead), + crypto_tfm_ctx_alignment()) + + align + 16; + + return 0; + +err_free_aead: + crypto_free_aead(aead); + return err; +} + +static void crypto_rfc4543_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_rfc4543_ctx *ctx = crypto_tfm_ctx(tfm); + + crypto_free_aead(ctx->child); + crypto_free_blkcipher(ctx->null); +} + +static struct crypto_instance *crypto_rfc4543_alloc(struct rtattr **tb) +{ + struct crypto_attr_type *algt; + struct crypto_instance *inst; + struct crypto_aead_spawn *spawn; + struct crypto_alg *alg; + struct crypto_rfc4543_instance_ctx *ctx; + const char *ccm_name; + int err; + + algt = crypto_get_attr_type(tb); + if (IS_ERR(algt)) + return ERR_CAST(algt); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return ERR_PTR(-EINVAL); + + ccm_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(ccm_name)) + return ERR_CAST(ccm_name); + + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + if (!inst) + return ERR_PTR(-ENOMEM); + + ctx = crypto_instance_ctx(inst); + spawn = &ctx->aead; + crypto_set_aead_spawn(spawn, inst); + err = crypto_grab_aead(spawn, ccm_name, 0, + crypto_requires_sync(algt->type, algt->mask)); + if (err) + goto out_free_inst; + + alg = crypto_aead_spawn_alg(spawn); + + crypto_set_skcipher_spawn(&ctx->null, inst); + err = crypto_grab_skcipher(&ctx->null, "ecb(cipher_null)", 0, + CRYPTO_ALG_ASYNC); + if (err) + goto out_drop_alg; + + crypto_skcipher_spawn_alg(&ctx->null); + + err = -EINVAL; + + /* We only support 16-byte blocks. */ + if (alg->cra_aead.ivsize != 16) + goto out_drop_ecbnull; + + /* Not a stream cipher? */ + if (alg->cra_blocksize != 1) + goto out_drop_ecbnull; + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, + "rfc4543(%s)", alg->cra_name) >= CRYPTO_MAX_ALG_NAME || + snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "rfc4543(%s)", alg->cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) + goto out_drop_ecbnull; + + inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD; + inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.cra_priority = alg->cra_priority; + inst->alg.cra_blocksize = 1; + inst->alg.cra_alignmask = alg->cra_alignmask; + inst->alg.cra_type = &crypto_nivaead_type; + + inst->alg.cra_aead.ivsize = 8; + inst->alg.cra_aead.maxauthsize = 16; + + inst->alg.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx); + + inst->alg.cra_init = crypto_rfc4543_init_tfm; + inst->alg.cra_exit = crypto_rfc4543_exit_tfm; + + inst->alg.cra_aead.setkey = crypto_rfc4543_setkey; + inst->alg.cra_aead.setauthsize = crypto_rfc4543_setauthsize; + inst->alg.cra_aead.encrypt = crypto_rfc4543_encrypt; + inst->alg.cra_aead.decrypt = crypto_rfc4543_decrypt; + + inst->alg.cra_aead.geniv = "seqiv"; + +out: + return inst; + +out_drop_ecbnull: + crypto_drop_skcipher(&ctx->null); +out_drop_alg: + crypto_drop_aead(spawn); +out_free_inst: + kfree(inst); + inst = ERR_PTR(err); + goto out; +} + +static void crypto_rfc4543_free(struct crypto_instance *inst) +{ + struct crypto_rfc4543_instance_ctx *ctx = crypto_instance_ctx(inst); + + crypto_drop_aead(&ctx->aead); + crypto_drop_skcipher(&ctx->null); + + kfree(inst); +} + +static struct crypto_template crypto_rfc4543_tmpl = { + .name = "rfc4543", + .alloc = crypto_rfc4543_alloc, + .free = crypto_rfc4543_free, + .module = THIS_MODULE, +}; + +static int __init crypto_gcm_module_init(void) +{ + int err; + + gcm_zeroes = kzalloc(16, GFP_KERNEL); + if (!gcm_zeroes) + return -ENOMEM; + + err = crypto_register_template(&crypto_gcm_base_tmpl); + if (err) + goto out; + + err = crypto_register_template(&crypto_gcm_tmpl); + if (err) + goto out_undo_base; + + err = crypto_register_template(&crypto_rfc4106_tmpl); + if (err) + goto out_undo_gcm; + + err = crypto_register_template(&crypto_rfc4543_tmpl); + if (err) + goto out_undo_rfc4106; + + return 0; + +out_undo_rfc4106: + crypto_unregister_template(&crypto_rfc4106_tmpl); +out_undo_gcm: + crypto_unregister_template(&crypto_gcm_tmpl); +out_undo_base: + crypto_unregister_template(&crypto_gcm_base_tmpl); +out: + kfree(gcm_zeroes); + return err; +} + +static void __exit crypto_gcm_module_exit(void) +{ + kfree(gcm_zeroes); + crypto_unregister_template(&crypto_rfc4543_tmpl); + crypto_unregister_template(&crypto_rfc4106_tmpl); + crypto_unregister_template(&crypto_gcm_tmpl); + crypto_unregister_template(&crypto_gcm_base_tmpl); +} + +module_init(crypto_gcm_module_init); +module_exit(crypto_gcm_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Galois/Counter Mode"); +MODULE_AUTHOR("Mikko Herranen <mh1@iki.fi>"); +MODULE_ALIAS_CRYPTO("gcm_base"); +MODULE_ALIAS_CRYPTO("rfc4106"); +MODULE_ALIAS_CRYPTO("rfc4543"); +MODULE_ALIAS_CRYPTO("gcm"); |