/* * 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/null.h> #include <crypto/scatterwalk.h> #include <crypto/gcm.h> #include <crypto/hash.h> #include "internal.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_skcipher *ctr; struct crypto_ahash *ghash; }; struct crypto_rfc4106_ctx { struct crypto_aead *child; u8 nonce[4]; }; struct crypto_rfc4106_req_ctx { struct scatterlist src[3]; struct scatterlist dst[3]; struct aead_request subreq; }; struct crypto_rfc4543_instance_ctx { struct crypto_aead_spawn aead; }; struct crypto_rfc4543_ctx { struct crypto_aead *child; struct crypto_skcipher *null; u8 nonce[4]; }; struct crypto_rfc4543_req_ctx { struct aead_request subreq; }; struct crypto_gcm_ghash_ctx { unsigned int cryptlen; struct scatterlist *src; int (*complete)(struct aead_request *req, u32 flags); }; struct crypto_gcm_req_priv_ctx { u8 iv[16]; u8 auth_tag[16]; u8 iauth_tag[16]; struct scatterlist src[3]; struct scatterlist dst[3]; struct scatterlist sg; struct crypto_gcm_ghash_ctx ghash_ctx; union { struct ahash_request ahreq; struct skcipher_request skreq; } u; }; static struct { u8 buf[16]; struct scatterlist sg; } *gcm_zeroes; static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc); 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 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_skcipher *ctr = ctx->ctr; struct { be128 hash; u8 iv[16]; struct crypto_wait wait; struct scatterlist sg[1]; struct skcipher_request req; } *data; int err; crypto_skcipher_clear_flags(ctr, CRYPTO_TFM_REQ_MASK); crypto_skcipher_set_flags(ctr, crypto_aead_get_flags(aead) & CRYPTO_TFM_REQ_MASK); err = crypto_skcipher_setkey(ctr, key, keylen); crypto_aead_set_flags(aead, crypto_skcipher_get_flags(ctr) & CRYPTO_TFM_RES_MASK); if (err) return err; data = kzalloc(sizeof(*data) + crypto_skcipher_reqsize(ctr), GFP_KERNEL); if (!data) return -ENOMEM; crypto_init_wait(&data->wait); sg_init_one(data->sg, &data->hash, sizeof(data->hash)); skcipher_request_set_tfm(&data->req, ctr); skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP | CRYPTO_TFM_REQ_MAY_BACKLOG, crypto_req_done, &data->wait); skcipher_request_set_crypt(&data->req, data->sg, data->sg, sizeof(data->hash), data->iv); err = crypto_wait_req(crypto_skcipher_encrypt(&data->req), &data->wait); 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: kzfree(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_common(struct aead_request *req) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); __be32 counter = cpu_to_be32(1); struct scatterlist *sg; memset(pctx->auth_tag, 0, sizeof(pctx->auth_tag)); memcpy(pctx->iv, req->iv, GCM_AES_IV_SIZE); memcpy(pctx->iv + GCM_AES_IV_SIZE, &counter, 4); sg_init_table(pctx->src, 3); sg_set_buf(pctx->src, pctx->auth_tag, sizeof(pctx->auth_tag)); sg = scatterwalk_ffwd(pctx->src + 1, req->src, req->assoclen); if (sg != pctx->src + 1) sg_chain(pctx->src, 2, sg); if (req->src != req->dst) { sg_init_table(pctx->dst, 3); sg_set_buf(pctx->dst, pctx->auth_tag, sizeof(pctx->auth_tag)); sg = scatterwalk_ffwd(pctx->dst + 1, req->dst, req->assoclen); if (sg != pctx->dst + 1) sg_chain(pctx->dst, 2, sg); } } static void crypto_gcm_init_crypt(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 skcipher_request *skreq = &pctx->u.skreq; struct scatterlist *dst; dst = req->src == req->dst ? pctx->src : pctx->dst; skcipher_request_set_tfm(skreq, ctx->ctr); skcipher_request_set_crypt(skreq, pctx->src, dst, cryptlen + sizeof(pctx->auth_tag), pctx->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 int gcm_hash_update(struct aead_request *req, crypto_completion_t compl, struct scatterlist *src, unsigned int len, u32 flags) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); struct ahash_request *ahreq = &pctx->u.ahreq; ahash_request_set_callback(ahreq, flags, compl, req); ahash_request_set_crypt(ahreq, src, NULL, len); return crypto_ahash_update(ahreq); } static int gcm_hash_remain(struct aead_request *req, unsigned int remain, crypto_completion_t compl, u32 flags) { return gcm_hash_update(req, compl, &gcm_zeroes->sg, remain, flags); } static int gcm_hash_len(struct aead_request *req, u32 flags) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 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->sg, pctx->iauth_tag, 16); ahash_request_set_callback(ahreq, flags, gcm_hash_len_done, req); ahash_request_set_crypt(ahreq, &pctx->sg, pctx->iauth_tag, sizeof(lengths)); return crypto_ahash_finup(ahreq); } static int gcm_hash_len_continue(struct aead_request *req, u32 flags) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; return gctx->complete(req, flags); } static void gcm_hash_len_done(struct crypto_async_request *areq, int err) { struct aead_request *req = areq->data; if (err) goto out; err = gcm_hash_len_continue(req, 0); if (err == -EINPROGRESS) return; out: aead_request_complete(req, err); } static int gcm_hash_crypt_remain_continue(struct aead_request *req, u32 flags) { return gcm_hash_len(req, flags) ?: gcm_hash_len_continue(req, flags); } static void gcm_hash_crypt_remain_done(struct crypto_async_request *areq, int err) { struct aead_request *req = areq->data; if (err) goto out; err = gcm_hash_crypt_remain_continue(req, 0); if (err == -EINPROGRESS) return; out: aead_request_complete(req, err); } static int gcm_hash_crypt_continue(struct aead_request *req, u32 flags) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; unsigned int remain; remain = gcm_remain(gctx->cryptlen); if (remain) return gcm_hash_remain(req, remain, gcm_hash_crypt_remain_done, flags) ?: gcm_hash_crypt_remain_continue(req, flags); return gcm_hash_crypt_remain_continue(req, flags); } static void gcm_hash_crypt_done(struct crypto_async_request *areq, int err) { struct aead_request *req = areq->data; if (err) goto out; err = gcm_hash_crypt_continue(req, 0); if (err == -EINPROGRESS) return; out: aead_request_complete(req, err); } static int gcm_hash_assoc_remain_continue(struct aead_request *req, u32 flags) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; if (gctx->cryptlen) return gcm_hash_update(req, gcm_hash_crypt_done, gctx->src, gctx->cryptlen, flags) ?: gcm_hash_crypt_continue(req, flags); return gcm_hash_crypt_remain_continue(req, flags); } static void gcm_hash_assoc_remain_done(struct crypto_async_request *areq, int err) { struct aead_request *req = areq->data; if (err) goto out; err = gcm_hash_assoc_remain_continue(req, 0); if (err == -EINPROGRESS) return; out: aead_request_complete(req, err); } static int gcm_hash_assoc_continue(struct aead_request *req, u32 flags) { unsigned int remain; remain = gcm_remain(req->assoclen); if (remain) return gcm_hash_remain(req, remain, gcm_hash_assoc_remain_done, flags) ?: gcm_hash_assoc_remain_continue(req, flags); return gcm_hash_assoc_remain_continue(req, flags); } static void gcm_hash_assoc_done(struct crypto_async_request *areq, int err) { struct aead_request *req = areq->data; if (err) goto out; err = gcm_hash_assoc_continue(req, 0); if (err == -EINPROGRESS) return; out: aead_request_complete(req, err); } static int gcm_hash_init_continue(struct aead_request *req, u32 flags) { if (req->assoclen) return gcm_hash_update(req, gcm_hash_assoc_done, req->src, req->assoclen, flags) ?: gcm_hash_assoc_continue(req, flags); return gcm_hash_assoc_remain_continue(req, flags); } static void gcm_hash_init_done(struct crypto_async_request *areq, int err) { struct aead_request *req = areq->data; if (err) goto out; err = gcm_hash_init_continue(req, 0); if (err == -EINPROGRESS) return; out: aead_request_complete(req, err); } static int gcm_hash(struct aead_request *req, u32 flags) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); struct ahash_request *ahreq = &pctx->u.ahreq; struct crypto_gcm_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req)); ahash_request_set_tfm(ahreq, ctx->ghash); ahash_request_set_callback(ahreq, flags, gcm_hash_init_done, req); return crypto_ahash_init(ahreq) ?: gcm_hash_init_continue(req, flags); } static int gcm_enc_copy_hash(struct aead_request *req, u32 flags) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); struct crypto_aead *aead = crypto_aead_reqtfm(req); u8 *auth_tag = pctx->auth_tag; crypto_xor(auth_tag, pctx->iauth_tag, 16); scatterwalk_map_and_copy(auth_tag, req->dst, req->assoclen + req->cryptlen, crypto_aead_authsize(aead), 1); return 0; } static int gcm_encrypt_continue(struct aead_request *req, u32 flags) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; gctx->src = sg_next(req->src == req->dst ? pctx->src : pctx->dst); gctx->cryptlen = req->cryptlen; gctx->complete = gcm_enc_copy_hash; return gcm_hash(req, flags); } static void gcm_encrypt_done(struct crypto_async_request *areq, int err) { struct aead_request *req = areq->data; if (err) goto out; err = gcm_encrypt_continue(req, 0); if (err == -EINPROGRESS) return; out: 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 skcipher_request *skreq = &pctx->u.skreq; u32 flags = aead_request_flags(req); crypto_gcm_init_common(req); crypto_gcm_init_crypt(req, req->cryptlen); skcipher_request_set_callback(skreq, flags, gcm_encrypt_done, req); return crypto_skcipher_encrypt(skreq) ?: gcm_encrypt_continue(req, flags); } static int crypto_gcm_verify(struct aead_request *req) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); 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, req->assoclen + 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; if (!err) err = crypto_gcm_verify(req); aead_request_complete(req, err); } static int gcm_dec_hash_continue(struct aead_request *req, u32 flags) { struct crypto_gcm_req_priv_ctx *pctx = crypto_gcm_reqctx(req); struct skcipher_request *skreq = &pctx->u.skreq; struct crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; crypto_gcm_init_crypt(req, gctx->cryptlen); skcipher_request_set_callback(skreq, flags, gcm_decrypt_done, req); return crypto_skcipher_decrypt(skreq) ?: crypto_gcm_verify(req); } 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 crypto_gcm_ghash_ctx *gctx = &pctx->ghash_ctx; unsigned int authsize = crypto_aead_authsize(aead); unsigned int cryptlen = req->cryptlen; u32 flags = aead_request_flags(req); cryptlen -= authsize; crypto_gcm_init_common(req); gctx->src = sg_next(pctx->src); gctx->cryptlen = cryptlen; gctx->complete = gcm_dec_hash_continue; return gcm_hash(req, flags); } static int crypto_gcm_init_tfm(struct crypto_aead *tfm) { struct aead_instance *inst = aead_alg_instance(tfm); struct gcm_instance_ctx *ictx = aead_instance_ctx(inst); struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm); struct crypto_skcipher *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_aead_alignmask(tfm); align &= ~(crypto_tfm_ctx_alignment() - 1); crypto_aead_set_reqsize(tfm, align + offsetof(struct crypto_gcm_req_priv_ctx, u) + max(sizeof(struct skcipher_request) + crypto_skcipher_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_aead *tfm) { struct crypto_gcm_ctx *ctx = crypto_aead_ctx(tfm); crypto_free_ahash(ctx->ghash); crypto_free_skcipher(ctx->ctr); } static void crypto_gcm_free(struct aead_instance *inst) { struct gcm_instance_ctx *ctx = aead_instance_ctx(inst); crypto_drop_skcipher(&ctx->ctr); crypto_drop_ahash(&ctx->ghash); kfree(inst); } static int crypto_gcm_create_common(struct crypto_template *tmpl, struct rtattr **tb, const char *full_name, const char *ctr_name, const char *ghash_name) { struct crypto_attr_type *algt; struct aead_instance *inst; struct skcipher_alg *ctr; struct crypto_alg *ghash_alg; struct hash_alg_common *ghash; struct gcm_instance_ctx *ctx; int err; algt = crypto_get_attr_type(tb); if (IS_ERR(algt)) return PTR_ERR(algt); if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) return -EINVAL; ghash_alg = crypto_find_alg(ghash_name, &crypto_ahash_type, CRYPTO_ALG_TYPE_HASH, CRYPTO_ALG_TYPE_AHASH_MASK | crypto_requires_sync(algt->type, algt->mask)); if (IS_ERR(ghash_alg)) return PTR_ERR(ghash_alg); ghash = __crypto_hash_alg_common(ghash_alg); err = -ENOMEM; inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); if (!inst) goto out_put_ghash; ctx = aead_instance_ctx(inst); err = crypto_init_ahash_spawn(&ctx->ghash, ghash, aead_crypto_instance(inst)); if (err) goto err_free_inst; err = -EINVAL; if (ghash->digestsize != 16) goto err_drop_ghash; crypto_set_skcipher_spawn(&ctx->ctr, aead_crypto_instance(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_spawn_skcipher_alg(&ctx->ctr); /* We only support 16-byte blocks. */ err = -EINVAL; if (crypto_skcipher_alg_ivsize(ctr) != 16) goto out_put_ctr; /* Not a stream cipher? */ if (ctr->base.cra_blocksize != 1) goto out_put_ctr; err = -ENAMETOOLONG; if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)", ctr->base.cra_driver_name, ghash_alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME) goto out_put_ctr; memcpy(inst->alg.base.cra_name, full_name, CRYPTO_MAX_ALG_NAME); inst->alg.base.cra_flags = (ghash->base.cra_flags | ctr->base.cra_flags) & CRYPTO_ALG_ASYNC; inst->alg.base.cra_priority = (ghash->base.cra_priority + ctr->base.cra_priority) / 2; inst->alg.base.cra_blocksize = 1; inst->alg.base.cra_alignmask = ghash->base.cra_alignmask | ctr->base.cra_alignmask; inst->alg.base.cra_ctxsize = sizeof(struct crypto_gcm_ctx); inst->alg.ivsize = GCM_AES_IV_SIZE; inst->alg.chunksize = crypto_skcipher_alg_chunksize(ctr); inst->alg.maxauthsize = 16; inst->alg.init = crypto_gcm_init_tfm; inst->alg.exit = crypto_gcm_exit_tfm; inst->alg.setkey = crypto_gcm_setkey; inst->alg.setauthsize = crypto_gcm_setauthsize; inst->alg.encrypt = crypto_gcm_encrypt; inst->alg.decrypt = crypto_gcm_decrypt; inst->free = crypto_gcm_free; err = aead_register_instance(tmpl, inst); if (err) goto out_put_ctr; out_put_ghash: crypto_mod_put(ghash_alg); return err; out_put_ctr: crypto_drop_skcipher(&ctx->ctr); err_drop_ghash: crypto_drop_ahash(&ctx->ghash); err_free_inst: kfree(inst); goto out_put_ghash; } static int crypto_gcm_create(struct crypto_template *tmpl, 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 PTR_ERR(cipher_name); if (snprintf(ctr_name, CRYPTO_MAX_ALG_NAME, "ctr(%s)", cipher_name) >= CRYPTO_MAX_ALG_NAME) return -ENAMETOOLONG; if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm(%s)", cipher_name) >= CRYPTO_MAX_ALG_NAME) return -ENAMETOOLONG; return crypto_gcm_create_common(tmpl, tb, full_name, ctr_name, "ghash"); } static struct crypto_template crypto_gcm_tmpl = { .name = "gcm", .create = crypto_gcm_create, .module = THIS_MODULE, }; static int crypto_gcm_base_create(struct crypto_template *tmpl, 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 PTR_ERR(ctr_name); ghash_name = crypto_attr_alg_name(tb[2]); if (IS_ERR(ghash_name)) return PTR_ERR(ghash_name); if (snprintf(full_name, CRYPTO_MAX_ALG_NAME, "gcm_base(%s,%s)", ctr_name, ghash_name) >= CRYPTO_MAX_ALG_NAME) return -ENAMETOOLONG; return crypto_gcm_create_common(tmpl, tb, full_name, ctr_name, ghash_name); } static struct crypto_template crypto_gcm_base_tmpl = { .name = "gcm_base", .create = crypto_gcm_base_create, .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 crypto_rfc4106_req_ctx *rctx = aead_request_ctx(req); struct crypto_aead *aead = crypto_aead_reqtfm(req); struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(aead); struct aead_request *subreq = &rctx->subreq; struct crypto_aead *child = ctx->child; struct scatterlist *sg; u8 *iv = PTR_ALIGN((u8 *)(subreq + 1) + crypto_aead_reqsize(child), crypto_aead_alignmask(child) + 1); scatterwalk_map_and_copy(iv + GCM_AES_IV_SIZE, req->src, 0, req->assoclen - 8, 0); memcpy(iv, ctx->nonce, 4); memcpy(iv + 4, req->iv, 8); sg_init_table(rctx->src, 3); sg_set_buf(rctx->src, iv + GCM_AES_IV_SIZE, req->assoclen - 8); sg = scatterwalk_ffwd(rctx->src + 1, req->src, req->assoclen); if (sg != rctx->src + 1) sg_chain(rctx->src, 2, sg); if (req->src != req->dst) { sg_init_table(rctx->dst, 3); sg_set_buf(rctx->dst, iv + GCM_AES_IV_SIZE, req->assoclen - 8); sg = scatterwalk_ffwd(rctx->dst + 1, req->dst, req->assoclen); if (sg != rctx->dst + 1) sg_chain(rctx->dst, 2, sg); } 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, rctx->src, req->src == req->dst ? rctx->src : rctx->dst, req->cryptlen, iv); aead_request_set_ad(subreq, req->assoclen - 8); return subreq; } static int crypto_rfc4106_encrypt(struct aead_request *req) { if (req->assoclen != 16 && req->assoclen != 20) return -EINVAL; req = crypto_rfc4106_crypt(req); return crypto_aead_encrypt(req); } static int crypto_rfc4106_decrypt(struct aead_request *req) { if (req->assoclen != 16 && req->assoclen != 20) return -EINVAL; req = crypto_rfc4106_crypt(req); return crypto_aead_decrypt(req); } static int crypto_rfc4106_init_tfm(struct crypto_aead *tfm) { struct aead_instance *inst = aead_alg_instance(tfm); struct crypto_aead_spawn *spawn = aead_instance_ctx(inst); struct crypto_rfc4106_ctx *ctx = crypto_aead_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); crypto_aead_set_reqsize( tfm, sizeof(struct crypto_rfc4106_req_ctx) + ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) + align + 24); return 0; } static void crypto_rfc4106_exit_tfm(struct crypto_aead *tfm) { struct crypto_rfc4106_ctx *ctx = crypto_aead_ctx(tfm); crypto_free_aead(ctx->child); } static void crypto_rfc4106_free(struct aead_instance *inst) { crypto_drop_aead(aead_instance_ctx(inst)); kfree(inst); } static int crypto_rfc4106_create(struct crypto_template *tmpl, struct rtattr **tb) { struct crypto_attr_type *algt; struct aead_instance *inst; struct crypto_aead_spawn *spawn; struct aead_alg *alg; const char *ccm_name; int err; algt = crypto_get_attr_type(tb); if (IS_ERR(algt)) return PTR_ERR(algt); if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) return -EINVAL; ccm_name = crypto_attr_alg_name(tb[1]); if (IS_ERR(ccm_name)) return PTR_ERR(ccm_name); inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); if (!inst) return -ENOMEM; spawn = aead_instance_ctx(inst); crypto_set_aead_spawn(spawn, aead_crypto_instance(inst)); err = crypto_grab_aead(spawn, ccm_name, 0, crypto_requires_sync(algt->type, algt->mask)); if (err) goto out_free_inst; alg = crypto_spawn_aead_alg(spawn); err = -EINVAL; /* Underlying IV size must be 12. */ if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE) goto out_drop_alg; /* Not a stream cipher? */ if (alg->base.cra_blocksize != 1) goto out_drop_alg; err = -ENAMETOOLONG; if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, "rfc4106(%s)", alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME || snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "rfc4106(%s)", alg->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME) goto out_drop_alg; 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 = 1; inst->alg.base.cra_alignmask = alg->base.cra_alignmask; inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4106_ctx); inst->alg.ivsize = GCM_RFC4106_IV_SIZE; inst->alg.chunksize = crypto_aead_alg_chunksize(alg); inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg); inst->alg.init = crypto_rfc4106_init_tfm; inst->alg.exit = crypto_rfc4106_exit_tfm; inst->alg.setkey = crypto_rfc4106_setkey; inst->alg.setauthsize = crypto_rfc4106_setauthsize; inst->alg.encrypt = crypto_rfc4106_encrypt; inst->alg.decrypt = crypto_rfc4106_decrypt; inst->free = crypto_rfc4106_free; err = aead_register_instance(tmpl, inst); if (err) goto out_drop_alg; out: return err; out_drop_alg: crypto_drop_aead(spawn); out_free_inst: kfree(inst); goto out; } static struct crypto_template crypto_rfc4106_tmpl = { .name = "rfc4106", .create = crypto_rfc4106_create, .module = THIS_MODULE, }; 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 int 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 = aead_request_ctx(req); struct aead_request *subreq = &rctx->subreq; unsigned int authsize = crypto_aead_authsize(aead); u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child), crypto_aead_alignmask(ctx->child) + 1); int err; if (req->src != req->dst) { err = crypto_rfc4543_copy_src_to_dst(req, enc); if (err) return err; } memcpy(iv, ctx->nonce, 4); memcpy(iv + 4, req->iv, 8); aead_request_set_tfm(subreq, ctx->child); aead_request_set_callback(subreq, req->base.flags, req->base.complete, req->base.data); aead_request_set_crypt(subreq, req->src, req->dst, enc ? 0 : authsize, iv); aead_request_set_ad(subreq, req->assoclen + req->cryptlen - subreq->cryptlen); return enc ? crypto_aead_encrypt(subreq) : crypto_aead_decrypt(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->assoclen + req->cryptlen - (enc ? 0 : authsize); SKCIPHER_REQUEST_ON_STACK(nreq, ctx->null); skcipher_request_set_tfm(nreq, ctx->null); skcipher_request_set_callback(nreq, req->base.flags, NULL, NULL); skcipher_request_set_crypt(nreq, req->src, req->dst, nbytes, NULL); return crypto_skcipher_encrypt(nreq); } static int crypto_rfc4543_encrypt(struct aead_request *req) { return crypto_rfc4543_crypt(req, true); } static int crypto_rfc4543_decrypt(struct aead_request *req) { return crypto_rfc4543_crypt(req, false); } static int crypto_rfc4543_init_tfm(struct crypto_aead *tfm) { struct aead_instance *inst = aead_alg_instance(tfm); struct crypto_rfc4543_instance_ctx *ictx = aead_instance_ctx(inst); struct crypto_aead_spawn *spawn = &ictx->aead; struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm); struct crypto_aead *aead; struct crypto_skcipher *null; unsigned long align; int err = 0; aead = crypto_spawn_aead(spawn); if (IS_ERR(aead)) return PTR_ERR(aead); null = crypto_get_default_null_skcipher2(); 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); crypto_aead_set_reqsize( tfm, sizeof(struct crypto_rfc4543_req_ctx) + ALIGN(crypto_aead_reqsize(aead), crypto_tfm_ctx_alignment()) + align + GCM_AES_IV_SIZE); return 0; err_free_aead: crypto_free_aead(aead); return err; } static void crypto_rfc4543_exit_tfm(struct crypto_aead *tfm) { struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(tfm); crypto_free_aead(ctx->child); crypto_put_default_null_skcipher2(); } static void crypto_rfc4543_free(struct aead_instance *inst) { struct crypto_rfc4543_instance_ctx *ctx = aead_instance_ctx(inst); crypto_drop_aead(&ctx->aead); kfree(inst); } static int crypto_rfc4543_create(struct crypto_template *tmpl, struct rtattr **tb) { struct crypto_attr_type *algt; struct aead_instance *inst; struct crypto_aead_spawn *spawn; struct aead_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 PTR_ERR(algt); if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask) return -EINVAL; ccm_name = crypto_attr_alg_name(tb[1]); if (IS_ERR(ccm_name)) return PTR_ERR(ccm_name); inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); if (!inst) return -ENOMEM; ctx = aead_instance_ctx(inst); spawn = &ctx->aead; crypto_set_aead_spawn(spawn, aead_crypto_instance(inst)); err = crypto_grab_aead(spawn, ccm_name, 0, crypto_requires_sync(algt->type, algt->mask)); if (err) goto out_free_inst; alg = crypto_spawn_aead_alg(spawn); err = -EINVAL; /* Underlying IV size must be 12. */ if (crypto_aead_alg_ivsize(alg) != GCM_AES_IV_SIZE) goto out_drop_alg; /* Not a stream cipher? */ if (alg->base.cra_blocksize != 1) goto out_drop_alg; err = -ENAMETOOLONG; if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, "rfc4543(%s)", alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME || snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "rfc4543(%s)", alg->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME) goto out_drop_alg; 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 = 1; inst->alg.base.cra_alignmask = alg->base.cra_alignmask; inst->alg.base.cra_ctxsize = sizeof(struct crypto_rfc4543_ctx); inst->alg.ivsize = GCM_RFC4543_IV_SIZE; inst->alg.chunksize = crypto_aead_alg_chunksize(alg); inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg); inst->alg.init = crypto_rfc4543_init_tfm; inst->alg.exit = crypto_rfc4543_exit_tfm; inst->alg.setkey = crypto_rfc4543_setkey; inst->alg.setauthsize = crypto_rfc4543_setauthsize; inst->alg.encrypt = crypto_rfc4543_encrypt; inst->alg.decrypt = crypto_rfc4543_decrypt; inst->free = crypto_rfc4543_free, err = aead_register_instance(tmpl, inst); if (err) goto out_drop_alg; out: return err; out_drop_alg: crypto_drop_aead(spawn); out_free_inst: kfree(inst); goto out; } static struct crypto_template crypto_rfc4543_tmpl = { .name = "rfc4543", .create = crypto_rfc4543_create, .module = THIS_MODULE, }; static int __init crypto_gcm_module_init(void) { int err; gcm_zeroes = kzalloc(sizeof(*gcm_zeroes), GFP_KERNEL); if (!gcm_zeroes) return -ENOMEM; sg_init_one(&gcm_zeroes->sg, gcm_zeroes->buf, sizeof(gcm_zeroes->buf)); 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");