From 5499b1a7311f5ec301ac2baa04a3482ee89ac0ab Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Thu, 9 Jul 2015 07:17:20 +0800 Subject: [PATCH] crypto: echainiv - Fix encryption convention This patch fixes a bug where we were incorrectly including the IV in the AD during encryption. The IV must remain in the plain text for it to be encrypted. During decryption there is no need to copy the IV to dst because it's now part of the AD. This patch removes an unncessary check on authsize which would be performed by the underlying decrypt call. Finally this patch makes use of the type-safe init/exit functions. Signed-off-by: Herbert Xu --- crypto/echainiv.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) diff --git a/crypto/echainiv.c b/crypto/echainiv.c index b6e43dc61356..d3896c7e634b 100644 --- a/crypto/echainiv.c +++ b/crypto/echainiv.c @@ -145,8 +145,8 @@ static int echainiv_encrypt(struct aead_request *req) aead_request_set_callback(subreq, req->base.flags, compl, data); aead_request_set_crypt(subreq, req->dst, req->dst, - req->cryptlen - ivsize, info); - aead_request_set_ad(subreq, req->assoclen + ivsize); + req->cryptlen, info); + aead_request_set_ad(subreq, req->assoclen); crypto_xor(info, ctx->salt, ivsize); scatterwalk_map_and_copy(info, req->dst, req->assoclen, ivsize, 1); @@ -166,7 +166,7 @@ static int echainiv_decrypt(struct aead_request *req) void *data; unsigned int ivsize = crypto_aead_ivsize(geniv); - if (req->cryptlen < ivsize + crypto_aead_authsize(geniv)) + if (req->cryptlen < ivsize) return -EINVAL; aead_request_set_tfm(subreq, ctx->geniv.child); @@ -180,16 +180,12 @@ static int echainiv_decrypt(struct aead_request *req) aead_request_set_ad(subreq, req->assoclen + ivsize); scatterwalk_map_and_copy(req->iv, req->src, req->assoclen, ivsize, 0); - if (req->src != req->dst) - scatterwalk_map_and_copy(req->iv, req->dst, - req->assoclen, ivsize, 1); return crypto_aead_decrypt(subreq); } -static int echainiv_init(struct crypto_tfm *tfm) +static int echainiv_init(struct crypto_aead *geniv) { - struct crypto_aead *geniv = __crypto_aead_cast(tfm); struct echainiv_ctx *ctx = crypto_aead_ctx(geniv); int err; @@ -212,7 +208,7 @@ static int echainiv_init(struct crypto_tfm *tfm) if (IS_ERR(ctx->null)) goto out; - err = aead_geniv_init(tfm); + err = aead_geniv_init(crypto_aead_tfm(geniv)); if (err) goto drop_null; @@ -227,9 +223,9 @@ drop_null: goto out; } -static void echainiv_exit(struct crypto_tfm *tfm) +static void echainiv_exit(struct crypto_aead *tfm) { - struct echainiv_ctx *ctx = crypto_tfm_ctx(tfm); + struct echainiv_ctx *ctx = crypto_aead_ctx(tfm); crypto_free_aead(ctx->geniv.child); crypto_put_default_null_skcipher(); @@ -262,13 +258,15 @@ static int echainiv_aead_create(struct crypto_template *tmpl, inst->alg.encrypt = echainiv_encrypt; inst->alg.decrypt = echainiv_decrypt; - inst->alg.base.cra_init = echainiv_init; - inst->alg.base.cra_exit = echainiv_exit; + inst->alg.init = echainiv_init; + inst->alg.exit = echainiv_exit; inst->alg.base.cra_alignmask |= __alignof__(u32) - 1; inst->alg.base.cra_ctxsize = sizeof(struct echainiv_ctx); inst->alg.base.cra_ctxsize += inst->alg.ivsize; + inst->free = aead_geniv_free; + done: err = aead_register_instance(tmpl, inst); if (err) -- 2.20.1