From: Eric Biggers <ebiggers@xxxxxxxxxx>
The new convention for akcipher_alg::verify makes it unclear which
values are the lengths of the signature and digest. Add local variables
to make it clearer what is going on.
Also rename the digest_size variable in pkcs1pad_sign(), as it is
actually the digest *info* size, not the digest size which is different.
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
crypto/rsa-pkcs1pad.c | 31 ++++++++++++++++---------------
1 file changed, 16 insertions(+), 15 deletions(-)
diff --git a/crypto/rsa-pkcs1pad.c b/crypto/rsa-pkcs1pad.c
index 9d804831c8b3f..3285e3af43e14 100644
--- a/crypto/rsa-pkcs1pad.c
+++ b/crypto/rsa-pkcs1pad.c
@@ -385,15 +385,15 @@ static int pkcs1pad_sign(struct akcipher_request *req)
struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
const struct rsa_asn1_template *digest_info = ictx->digest_info;
int err;
- unsigned int ps_end, digest_size = 0;
+ unsigned int ps_end, digest_info_size = 0;
if (!ctx->key_size)
return -EINVAL;
if (digest_info)
- digest_size = digest_info->size;
+ digest_info_size = digest_info->size;
- if (req->src_len + digest_size > ctx->key_size - 11)
+ if (req->src_len + digest_info_size > ctx->key_size - 11)
return -EOVERFLOW;
if (req->dst_len < ctx->key_size) {
@@ -406,7 +406,7 @@ static int pkcs1pad_sign(struct akcipher_request *req)
if (!req_ctx->in_buf)
return -ENOMEM;
- ps_end = ctx->key_size - digest_size - req->src_len - 2;
+ ps_end = ctx->key_size - digest_info_size - req->src_len - 2;
req_ctx->in_buf[0] = 0x01;
memset(req_ctx->in_buf + 1, 0xff, ps_end - 1);
req_ctx->in_buf[ps_end] = 0x00;
@@ -441,6 +441,8 @@ static int pkcs1pad_verify_complete(struct akcipher_request *req, int err)
struct akcipher_instance *inst = akcipher_alg_instance(tfm);
struct pkcs1pad_inst_ctx *ictx = akcipher_instance_ctx(inst);
const struct rsa_asn1_template *digest_info = ictx->digest_info;
+ const unsigned int sig_size = req->src_len;
+ const unsigned int digest_size = req->dst_len;
unsigned int dst_len;
unsigned int pos;
u8 *out_buf;
@@ -487,20 +489,19 @@ static int pkcs1pad_verify_complete(struct akcipher_request *req, int err)
err = 0;
- if (req->dst_len != dst_len - pos) {
+ if (digest_size != dst_len - pos) {
err = -EKEYREJECTED;
req->dst_len = dst_len - pos;
goto done;
}
/* Extract appended digest. */
sg_pcopy_to_buffer(req->src,
- sg_nents_for_len(req->src,
- req->src_len + req->dst_len),
+ sg_nents_for_len(req->src, sig_size + digest_size),
req_ctx->out_buf + ctx->key_size,
- req->dst_len, req->src_len);
+ digest_size, sig_size);
/* Do the actual verification step. */
if (memcmp(req_ctx->out_buf + ctx->key_size, out_buf + pos,
- req->dst_len) != 0)
+ digest_size) != 0)
err = -EKEYREJECTED;
done:
kfree_sensitive(req_ctx->out_buf);
@@ -536,14 +537,15 @@ static int pkcs1pad_verify(struct akcipher_request *req)
struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req);
struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm);
struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req);
+ const unsigned int sig_size = req->src_len;
+ const unsigned int digest_size = req->dst_len;
int err;
- if (WARN_ON(req->dst) ||
- WARN_ON(!req->dst_len) ||
- !ctx->key_size || req->src_len != ctx->key_size)
+ if (WARN_ON(req->dst) || WARN_ON(!digest_size) ||
+ !ctx->key_size || sig_size != ctx->key_size)
return -EINVAL;
- req_ctx->out_buf = kmalloc(ctx->key_size + req->dst_len, GFP_KERNEL);
+ req_ctx->out_buf = kmalloc(ctx->key_size + digest_size, GFP_KERNEL);
if (!req_ctx->out_buf)
return -ENOMEM;
@@ -556,8 +558,7 @@ static int pkcs1pad_verify(struct akcipher_request *req)
/* Reuse input buffer, output to a new buffer */
akcipher_request_set_crypt(&req_ctx->child_req, req->src,
- req_ctx->out_sg, req->src_len,
- ctx->key_size);
+ req_ctx->out_sg, sig_size, ctx->key_size);
err = crypto_akcipher_encrypt(&req_ctx->child_req);
if (err != -EINPROGRESS && err != -EBUSY)
--
2.34.1
