diff options
Diffstat (limited to 'crypto/gcm.c')
-rw-r--r-- | crypto/gcm.c | 116 |
1 files changed, 97 insertions, 19 deletions
diff --git a/crypto/gcm.c b/crypto/gcm.c index 13ccbda34ff..43e1fb05ea5 100644 --- a/crypto/gcm.c +++ b/crypto/gcm.c @@ -37,8 +37,14 @@ struct crypto_rfc4106_ctx { 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]; }; @@ -1094,21 +1100,36 @@ static int crypto_rfc4543_setauthsize(struct crypto_aead *parent, 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, - int enc) + 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 *dst = req->dst; + 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 *dstp; - u8 *vdst; + struct page *srcp; + u8 *vsrc; u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child), crypto_aead_alignmask(ctx->child) + 1); @@ -1119,19 +1140,19 @@ static struct aead_request *crypto_rfc4543_crypt(struct aead_request *req, if (enc) memset(rctx->auth_tag, 0, authsize); else - scatterwalk_map_and_copy(rctx->auth_tag, dst, + scatterwalk_map_and_copy(rctx->auth_tag, src, req->cryptlen - authsize, authsize, 0); sg_init_one(cipher, rctx->auth_tag, authsize); /* construct the aad */ - dstp = sg_page(dst); - vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset; + 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, dst, vdst == req->iv + 8, 2); + scatterwalk_crypto_chain(payload, src, vsrc == req->iv + 8, 2); assoclen += 8 + req->cryptlen - (enc ? 0 : authsize); if (req->assoc->length == req->assoclen) { @@ -1150,14 +1171,27 @@ static struct aead_request *crypto_rfc4543_crypt(struct aead_request *req, scatterwalk_crypto_chain(assoc, payload, 0, 2); aead_request_set_tfm(subreq, ctx->child); - aead_request_set_callback(subreq, req->base.flags, req->base.complete, - req->base.data); + 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); @@ -1165,7 +1199,13 @@ static int crypto_rfc4543_encrypt(struct aead_request *req) struct aead_request *subreq; int err; - subreq = crypto_rfc4543_crypt(req, 1); + 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; @@ -1178,7 +1218,15 @@ static int crypto_rfc4543_encrypt(struct aead_request *req) static int crypto_rfc4543_decrypt(struct aead_request *req) { - req = crypto_rfc4543_crypt(req, 0); + 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); } @@ -1186,16 +1234,25 @@ static int crypto_rfc4543_decrypt(struct aead_request *req) static int crypto_rfc4543_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_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); @@ -1205,6 +1262,10 @@ static int crypto_rfc4543_init_tfm(struct crypto_tfm *tfm) align + 16; return 0; + +err_free_aead: + crypto_free_aead(aead); + return err; } static void crypto_rfc4543_exit_tfm(struct crypto_tfm *tfm) @@ -1212,6 +1273,7 @@ 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) @@ -1220,6 +1282,7 @@ static struct crypto_instance *crypto_rfc4543_alloc(struct rtattr **tb) 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; @@ -1234,11 +1297,12 @@ static struct crypto_instance *crypto_rfc4543_alloc(struct rtattr **tb) if (IS_ERR(ccm_name)) return ERR_CAST(ccm_name); - inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL); if (!inst) return ERR_PTR(-ENOMEM); - spawn = crypto_instance_ctx(inst); + 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)); @@ -1247,15 +1311,23 @@ static struct crypto_instance *crypto_rfc4543_alloc(struct rtattr **tb) 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_alg; + goto out_drop_ecbnull; /* Not a stream cipher? */ if (alg->cra_blocksize != 1) - goto out_drop_alg; + goto out_drop_ecbnull; err = -ENAMETOOLONG; if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, @@ -1263,7 +1335,7 @@ static struct crypto_instance *crypto_rfc4543_alloc(struct rtattr **tb) snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "rfc4543(%s)", alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME) - goto out_drop_alg; + goto out_drop_ecbnull; inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD; inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC; @@ -1290,6 +1362,8 @@ static struct crypto_instance *crypto_rfc4543_alloc(struct rtattr **tb) out: return inst; +out_drop_ecbnull: + crypto_drop_skcipher(&ctx->null); out_drop_alg: crypto_drop_aead(spawn); out_free_inst: @@ -1300,7 +1374,11 @@ out_free_inst: static void crypto_rfc4543_free(struct crypto_instance *inst) { - crypto_drop_spawn(crypto_instance_ctx(inst)); + struct crypto_rfc4543_instance_ctx *ctx = crypto_instance_ctx(inst); + + crypto_drop_aead(&ctx->aead); + crypto_drop_skcipher(&ctx->null); + kfree(inst); } |