/* * 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_gcm_ghash_ctx { unsigned int cryptlen; struct scatterlist *src; crypto_completion_t complete; }; 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 complete, struct scatterlist *src, unsigned int len) { struct ahash_request *ahreq = &pctx->u.ahreq; ahash_request_set_callback(ahreq, aead_request_flags(req), complete, 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 complete) { struct ahash_request *ahreq = &pctx->u.ahreq; ahash_request_set_callback(ahreq, aead_request_flags(req), complete, 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 crypto_async_request *areq, int err) { struct aead_request *req = areq->data; 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(areq, err); } static void gcm_hash_len_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_final(req, pctx); if (err == -EINPROGRESS || err == -EBUSY) return; } gcm_hash_final_done(areq, err); } static void gcm_hash_crypt_remain_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_len(req, pctx); if (err == -EINPROGRESS || err == -EBUSY) return; } gcm_hash_len_done(areq, err); } static void gcm_hash_crypt_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); 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(areq, err); } static void gcm_hash_assoc_remain_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); struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; crypto_completion_t complete; unsigned int remain = 0; if (!err && gctx->cryptlen) { remain = gcm_remain(gctx->cryptlen); complete = remain ? gcm_hash_crypt_done : gcm_hash_crypt_remain_done; err = gcm_hash_update(req, pctx, complete, gctx->src, gctx->cryptlen); if (err == -EINPROGRESS || err == -EBUSY) return; } if (remain) gcm_hash_crypt_done(areq, err); else gcm_hash_crypt_remain_done(areq, err); } static void gcm_hash_assoc_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); 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(areq, err); } static void gcm_hash_init_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); crypto_completion_t complete; unsigned int remain = 0; if (!err && req->assoclen) { remain = gcm_remain(req->assoclen); complete = remain ? gcm_hash_assoc_done : gcm_hash_assoc_remain_done; err = gcm_hash_update(req, pctx, complete, req->assoc, req->assoclen); if (err == -EINPROGRESS || err == -EBUSY) return; } if (remain) gcm_hash_assoc_done(areq, err); else gcm_hash_assoc_remain_done(areq, 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 complete; 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); complete = remain ? gcm_hash_assoc_done : gcm_hash_assoc_remain_done; err = gcm_hash_update(req, pctx, complete, 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); complete = remain ? gcm_hash_crypt_done : gcm_hash_crypt_remain_done; err = gcm_hash_update(req, pctx, complete, 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 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) 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; } gcm_enc_hash_done(areq, 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 memcmp(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 crypto_async_request *areq, int err) { struct aead_request *req = areq->data; 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; } gcm_decrypt_done(areq, 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); 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); ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type, CRYPTO_ALG_TYPE_HASH, CRYPTO_ALG_TYPE_AHASH_MASK); err = PTR_ERR(ghash_alg); if (IS_ERR(ghash_alg)) return ERR_PTR(err); 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) { int err; 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]); err = PTR_ERR(cipher_name); if (IS_ERR(cipher_name)) return ERR_PTR(err); 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) { int err; const char *ctr_name; const char *ghash_name; char full_name[CRYPTO_MAX_ALG_NAME]; ctr_name = crypto_attr_alg_name(tb[1]); err = PTR_ERR(ctr_name); if (IS_ERR(ctr_name)) return ERR_PTR(err); ghash_name = crypto_attr_alg_name(tb[2]); err = PTR_ERR(ghash_name); if (IS_ERR(ghash_name)) return ERR_PTR(err); 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); 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); ccm_name = crypto_attr_alg_name(tb[1]); err = PTR_ERR(ccm_name); if (IS_ERR(ccm_name)) return ERR_PTR(err); 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 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; return 0; 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_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("gcm_base"); MODULE_ALIAS("rfc4106");