Commit c2a28fdb authored by Eric Biggers's avatar Eric Biggers Committed by Herbert Xu
Browse files

crypto: rsa-pkcs1pad - use clearer variable names 



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: default avatarEric Biggers <ebiggers@google.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent a24611ea

crypto/rsa-pkcs1pad.c

+16 −15
Original line number Diff line number Diff line
@@ -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)