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 <herbert@gondor.apana.org.au>
diff --git a/crypto/echainiv.c b/crypto/echainiv.c
index b6e43dc..d3896c7 100644
--- a/crypto/echainiv.c
+++ b/crypto/echainiv.c
@@ -145,8 +145,8 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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)