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author | Timothy Pearson <tpearson@raptorengineering.com> | 2017-08-23 14:45:25 -0500 |
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committer | Timothy Pearson <tpearson@raptorengineering.com> | 2017-08-23 14:45:25 -0500 |
commit | fcbb27b0ec6dcbc5a5108cb8fb19eae64593d204 (patch) | |
tree | 22962a4387943edc841c72a4e636a068c66d58fd /crypto/authenc.c | |
download | ast2050-linux-kernel-fcbb27b0ec6dcbc5a5108cb8fb19eae64593d204.zip ast2050-linux-kernel-fcbb27b0ec6dcbc5a5108cb8fb19eae64593d204.tar.gz |
Initial import of modified Linux 2.6.28 tree
Original upstream URL:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git | branch linux-2.6.28.y
Diffstat (limited to 'crypto/authenc.c')
-rw-r--r-- | crypto/authenc.c | 497 |
1 files changed, 497 insertions, 0 deletions
diff --git a/crypto/authenc.c b/crypto/authenc.c new file mode 100644 index 0000000..0861dc2 --- /dev/null +++ b/crypto/authenc.c @@ -0,0 +1,497 @@ +/* + * Authenc: Simple AEAD wrapper for IPsec + * + * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + * + */ + +#include <crypto/aead.h> +#include <crypto/internal/skcipher.h> +#include <crypto/authenc.h> +#include <crypto/scatterwalk.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/rtnetlink.h> +#include <linux/slab.h> +#include <linux/spinlock.h> + +struct authenc_instance_ctx { + struct crypto_spawn auth; + struct crypto_skcipher_spawn enc; +}; + +struct crypto_authenc_ctx { + spinlock_t auth_lock; + struct crypto_hash *auth; + struct crypto_ablkcipher *enc; +}; + +static int crypto_authenc_setkey(struct crypto_aead *authenc, const u8 *key, + unsigned int keylen) +{ + unsigned int authkeylen; + unsigned int enckeylen; + struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); + struct crypto_hash *auth = ctx->auth; + struct crypto_ablkcipher *enc = ctx->enc; + struct rtattr *rta = (void *)key; + struct crypto_authenc_key_param *param; + int err = -EINVAL; + + if (!RTA_OK(rta, keylen)) + goto badkey; + if (rta->rta_type != CRYPTO_AUTHENC_KEYA_PARAM) + goto badkey; + if (RTA_PAYLOAD(rta) < sizeof(*param)) + goto badkey; + + param = RTA_DATA(rta); + enckeylen = be32_to_cpu(param->enckeylen); + + key += RTA_ALIGN(rta->rta_len); + keylen -= RTA_ALIGN(rta->rta_len); + + if (keylen < enckeylen) + goto badkey; + + authkeylen = keylen - enckeylen; + + crypto_hash_clear_flags(auth, CRYPTO_TFM_REQ_MASK); + crypto_hash_set_flags(auth, crypto_aead_get_flags(authenc) & + CRYPTO_TFM_REQ_MASK); + err = crypto_hash_setkey(auth, key, authkeylen); + crypto_aead_set_flags(authenc, crypto_hash_get_flags(auth) & + CRYPTO_TFM_RES_MASK); + + if (err) + goto out; + + crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK); + crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc) & + CRYPTO_TFM_REQ_MASK); + err = crypto_ablkcipher_setkey(enc, key + authkeylen, enckeylen); + crypto_aead_set_flags(authenc, crypto_ablkcipher_get_flags(enc) & + CRYPTO_TFM_RES_MASK); + +out: + return err; + +badkey: + crypto_aead_set_flags(authenc, CRYPTO_TFM_RES_BAD_KEY_LEN); + goto out; +} + +static void authenc_chain(struct scatterlist *head, struct scatterlist *sg, + int chain) +{ + if (chain) { + head->length += sg->length; + sg = scatterwalk_sg_next(sg); + } + + if (sg) + scatterwalk_sg_chain(head, 2, sg); + else + sg_mark_end(head); +} + +static u8 *crypto_authenc_hash(struct aead_request *req, unsigned int flags, + struct scatterlist *cipher, + unsigned int cryptlen) +{ + struct crypto_aead *authenc = crypto_aead_reqtfm(req); + struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); + struct crypto_hash *auth = ctx->auth; + struct hash_desc desc = { + .tfm = auth, + .flags = aead_request_flags(req) & flags, + }; + u8 *hash = aead_request_ctx(req); + int err; + + hash = (u8 *)ALIGN((unsigned long)hash + crypto_hash_alignmask(auth), + crypto_hash_alignmask(auth) + 1); + + spin_lock_bh(&ctx->auth_lock); + err = crypto_hash_init(&desc); + if (err) + goto auth_unlock; + + err = crypto_hash_update(&desc, req->assoc, req->assoclen); + if (err) + goto auth_unlock; + + err = crypto_hash_update(&desc, cipher, cryptlen); + if (err) + goto auth_unlock; + + err = crypto_hash_final(&desc, hash); +auth_unlock: + spin_unlock_bh(&ctx->auth_lock); + + if (err) + return ERR_PTR(err); + + return hash; +} + +static int crypto_authenc_genicv(struct aead_request *req, u8 *iv, + unsigned int flags) +{ + struct crypto_aead *authenc = crypto_aead_reqtfm(req); + struct scatterlist *dst = req->dst; + struct scatterlist cipher[2]; + struct page *dstp; + unsigned int ivsize = crypto_aead_ivsize(authenc); + unsigned int cryptlen; + u8 *vdst; + u8 *hash; + + dstp = sg_page(dst); + vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset; + + if (ivsize) { + sg_init_table(cipher, 2); + sg_set_buf(cipher, iv, ivsize); + authenc_chain(cipher, dst, vdst == iv + ivsize); + dst = cipher; + } + + cryptlen = req->cryptlen + ivsize; + hash = crypto_authenc_hash(req, flags, dst, cryptlen); + if (IS_ERR(hash)) + return PTR_ERR(hash); + + scatterwalk_map_and_copy(hash, dst, cryptlen, + crypto_aead_authsize(authenc), 1); + return 0; +} + +static void crypto_authenc_encrypt_done(struct crypto_async_request *req, + int err) +{ + struct aead_request *areq = req->data; + + if (!err) { + struct crypto_aead *authenc = crypto_aead_reqtfm(areq); + struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); + struct ablkcipher_request *abreq = aead_request_ctx(areq); + u8 *iv = (u8 *)(abreq + 1) + + crypto_ablkcipher_reqsize(ctx->enc); + + err = crypto_authenc_genicv(areq, iv, 0); + } + + aead_request_complete(areq, err); +} + +static int crypto_authenc_encrypt(struct aead_request *req) +{ + struct crypto_aead *authenc = crypto_aead_reqtfm(req); + struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); + struct ablkcipher_request *abreq = aead_request_ctx(req); + struct crypto_ablkcipher *enc = ctx->enc; + struct scatterlist *dst = req->dst; + unsigned int cryptlen = req->cryptlen; + u8 *iv = (u8 *)(abreq + 1) + crypto_ablkcipher_reqsize(enc); + int err; + + ablkcipher_request_set_tfm(abreq, enc); + ablkcipher_request_set_callback(abreq, aead_request_flags(req), + crypto_authenc_encrypt_done, req); + ablkcipher_request_set_crypt(abreq, req->src, dst, cryptlen, req->iv); + + memcpy(iv, req->iv, crypto_aead_ivsize(authenc)); + + err = crypto_ablkcipher_encrypt(abreq); + if (err) + return err; + + return crypto_authenc_genicv(req, iv, CRYPTO_TFM_REQ_MAY_SLEEP); +} + +static void crypto_authenc_givencrypt_done(struct crypto_async_request *req, + int err) +{ + struct aead_request *areq = req->data; + + if (!err) { + struct skcipher_givcrypt_request *greq = aead_request_ctx(areq); + + err = crypto_authenc_genicv(areq, greq->giv, 0); + } + + aead_request_complete(areq, err); +} + +static int crypto_authenc_givencrypt(struct aead_givcrypt_request *req) +{ + struct crypto_aead *authenc = aead_givcrypt_reqtfm(req); + struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); + struct aead_request *areq = &req->areq; + struct skcipher_givcrypt_request *greq = aead_request_ctx(areq); + u8 *iv = req->giv; + int err; + + skcipher_givcrypt_set_tfm(greq, ctx->enc); + skcipher_givcrypt_set_callback(greq, aead_request_flags(areq), + crypto_authenc_givencrypt_done, areq); + skcipher_givcrypt_set_crypt(greq, areq->src, areq->dst, areq->cryptlen, + areq->iv); + skcipher_givcrypt_set_giv(greq, iv, req->seq); + + err = crypto_skcipher_givencrypt(greq); + if (err) + return err; + + return crypto_authenc_genicv(areq, iv, CRYPTO_TFM_REQ_MAY_SLEEP); +} + +static int crypto_authenc_verify(struct aead_request *req, + struct scatterlist *cipher, + unsigned int cryptlen) +{ + struct crypto_aead *authenc = crypto_aead_reqtfm(req); + u8 *ohash; + u8 *ihash; + unsigned int authsize; + + ohash = crypto_authenc_hash(req, CRYPTO_TFM_REQ_MAY_SLEEP, cipher, + cryptlen); + if (IS_ERR(ohash)) + return PTR_ERR(ohash); + + authsize = crypto_aead_authsize(authenc); + ihash = ohash + authsize; + scatterwalk_map_and_copy(ihash, cipher, cryptlen, authsize, 0); + return memcmp(ihash, ohash, authsize) ? -EBADMSG: 0; +} + +static int crypto_authenc_iverify(struct aead_request *req, u8 *iv, + unsigned int cryptlen) +{ + struct crypto_aead *authenc = crypto_aead_reqtfm(req); + struct scatterlist *src = req->src; + struct scatterlist cipher[2]; + struct page *srcp; + unsigned int ivsize = crypto_aead_ivsize(authenc); + u8 *vsrc; + + srcp = sg_page(src); + vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset; + + if (ivsize) { + sg_init_table(cipher, 2); + sg_set_buf(cipher, iv, ivsize); + authenc_chain(cipher, src, vsrc == iv + ivsize); + src = cipher; + } + + return crypto_authenc_verify(req, src, cryptlen + ivsize); +} + +static int crypto_authenc_decrypt(struct aead_request *req) +{ + struct crypto_aead *authenc = crypto_aead_reqtfm(req); + struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc); + struct ablkcipher_request *abreq = aead_request_ctx(req); + unsigned int cryptlen = req->cryptlen; + unsigned int authsize = crypto_aead_authsize(authenc); + u8 *iv = req->iv; + int err; + + if (cryptlen < authsize) + return -EINVAL; + cryptlen -= authsize; + + err = crypto_authenc_iverify(req, iv, cryptlen); + if (err) + return err; + + ablkcipher_request_set_tfm(abreq, ctx->enc); + ablkcipher_request_set_callback(abreq, aead_request_flags(req), + req->base.complete, req->base.data); + ablkcipher_request_set_crypt(abreq, req->src, req->dst, cryptlen, iv); + + return crypto_ablkcipher_decrypt(abreq); +} + +static int crypto_authenc_init_tfm(struct crypto_tfm *tfm) +{ + struct crypto_instance *inst = (void *)tfm->__crt_alg; + struct authenc_instance_ctx *ictx = crypto_instance_ctx(inst); + struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm); + struct crypto_hash *auth; + struct crypto_ablkcipher *enc; + int err; + + auth = crypto_spawn_hash(&ictx->auth); + if (IS_ERR(auth)) + return PTR_ERR(auth); + + enc = crypto_spawn_skcipher(&ictx->enc); + err = PTR_ERR(enc); + if (IS_ERR(enc)) + goto err_free_hash; + + ctx->auth = auth; + ctx->enc = enc; + tfm->crt_aead.reqsize = max_t(unsigned int, + (crypto_hash_alignmask(auth) & + ~(crypto_tfm_ctx_alignment() - 1)) + + crypto_hash_digestsize(auth) * 2, + sizeof(struct skcipher_givcrypt_request) + + crypto_ablkcipher_reqsize(enc) + + crypto_ablkcipher_ivsize(enc)); + + spin_lock_init(&ctx->auth_lock); + + return 0; + +err_free_hash: + crypto_free_hash(auth); + return err; +} + +static void crypto_authenc_exit_tfm(struct crypto_tfm *tfm) +{ + struct crypto_authenc_ctx *ctx = crypto_tfm_ctx(tfm); + + crypto_free_hash(ctx->auth); + crypto_free_ablkcipher(ctx->enc); +} + +static struct crypto_instance *crypto_authenc_alloc(struct rtattr **tb) +{ + struct crypto_attr_type *algt; + struct crypto_instance *inst; + struct crypto_alg *auth; + struct crypto_alg *enc; + struct authenc_instance_ctx *ctx; + const char *enc_name; + int err; + + algt = crypto_get_attr_type(tb); + err = PTR_ERR(algt); + if (IS_ERR(algt)) + return ERR_PTR(err); + + if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) + return ERR_PTR(-EINVAL); + + auth = crypto_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH, + CRYPTO_ALG_TYPE_HASH_MASK); + if (IS_ERR(auth)) + return ERR_PTR(PTR_ERR(auth)); + + enc_name = crypto_attr_alg_name(tb[2]); + err = PTR_ERR(enc_name); + if (IS_ERR(enc_name)) + goto out_put_auth; + + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); + err = -ENOMEM; + if (!inst) + goto out_put_auth; + + ctx = crypto_instance_ctx(inst); + + err = crypto_init_spawn(&ctx->auth, auth, inst, CRYPTO_ALG_TYPE_MASK); + if (err) + goto err_free_inst; + + crypto_set_skcipher_spawn(&ctx->enc, inst); + err = crypto_grab_skcipher(&ctx->enc, enc_name, 0, + crypto_requires_sync(algt->type, + algt->mask)); + if (err) + goto err_drop_auth; + + enc = crypto_skcipher_spawn_alg(&ctx->enc); + + err = -ENAMETOOLONG; + if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, + "authenc(%s,%s)", auth->cra_name, enc->cra_name) >= + CRYPTO_MAX_ALG_NAME) + goto err_drop_enc; + + if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "authenc(%s,%s)", auth->cra_driver_name, + enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME) + goto err_drop_enc; + + inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD; + inst->alg.cra_flags |= enc->cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.cra_priority = enc->cra_priority * 10 + auth->cra_priority; + inst->alg.cra_blocksize = enc->cra_blocksize; + inst->alg.cra_alignmask = auth->cra_alignmask | enc->cra_alignmask; + inst->alg.cra_type = &crypto_aead_type; + + inst->alg.cra_aead.ivsize = enc->cra_ablkcipher.ivsize; + inst->alg.cra_aead.maxauthsize = auth->cra_type == &crypto_hash_type ? + auth->cra_hash.digestsize : + auth->cra_digest.dia_digestsize; + + inst->alg.cra_ctxsize = sizeof(struct crypto_authenc_ctx); + + inst->alg.cra_init = crypto_authenc_init_tfm; + inst->alg.cra_exit = crypto_authenc_exit_tfm; + + inst->alg.cra_aead.setkey = crypto_authenc_setkey; + inst->alg.cra_aead.encrypt = crypto_authenc_encrypt; + inst->alg.cra_aead.decrypt = crypto_authenc_decrypt; + inst->alg.cra_aead.givencrypt = crypto_authenc_givencrypt; + +out: + crypto_mod_put(auth); + return inst; + +err_drop_enc: + crypto_drop_skcipher(&ctx->enc); +err_drop_auth: + crypto_drop_spawn(&ctx->auth); +err_free_inst: + kfree(inst); +out_put_auth: + inst = ERR_PTR(err); + goto out; +} + +static void crypto_authenc_free(struct crypto_instance *inst) +{ + struct authenc_instance_ctx *ctx = crypto_instance_ctx(inst); + + crypto_drop_skcipher(&ctx->enc); + crypto_drop_spawn(&ctx->auth); + kfree(inst); +} + +static struct crypto_template crypto_authenc_tmpl = { + .name = "authenc", + .alloc = crypto_authenc_alloc, + .free = crypto_authenc_free, + .module = THIS_MODULE, +}; + +static int __init crypto_authenc_module_init(void) +{ + return crypto_register_template(&crypto_authenc_tmpl); +} + +static void __exit crypto_authenc_module_exit(void) +{ + crypto_unregister_template(&crypto_authenc_tmpl); +} + +module_init(crypto_authenc_module_init); +module_exit(crypto_authenc_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Simple AEAD wrapper for IPsec"); |