From: Roberto Sassu <roberto.sassu@huawei.com>
To: <dhowells@redhat.com>, <dwmw2@infradead.org>,
<herbert@gondor.apana.org.au>, <davem@davemloft.net>
Cc: <keyrings@vger.kernel.org>, <linux-crypto@vger.kernel.org>,
<linux-integrity@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
<silviu.vlasceanu@huawei.com>,
Roberto Sassu <roberto.sassu@huawei.com>
Subject: [RFC][PATCH 01/12] mpi: introduce mpi_key_length()
Date: Mon, 12 Nov 2018 11:24:12 +0100 [thread overview]
Message-ID: <20181112102423.30415-2-roberto.sassu@huawei.com> (raw)
In-Reply-To: <20181112102423.30415-1-roberto.sassu@huawei.com>
Introduce the new function to get the number of bits and bytes from an MPI.
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
---
include/linux/mpi.h | 2 ++
lib/mpi/mpicoder.c | 33 ++++++++++++++++++++++++++-------
2 files changed, 28 insertions(+), 7 deletions(-)
diff --git a/include/linux/mpi.h b/include/linux/mpi.h
index 7cd1473c64a4..56187bb57c78 100644
--- a/include/linux/mpi.h
+++ b/include/linux/mpi.h
@@ -61,6 +61,8 @@ int mpi_resize(MPI a, unsigned nlimbs);
/*-- mpicoder.c --*/
MPI mpi_read_raw_data(const void *xbuffer, size_t nbytes);
+int mpi_key_length(const void *xbuffer, unsigned int ret_nread,
+ unsigned int *nbits_arg, unsigned int *nbytes_arg);
MPI mpi_read_from_buffer(const void *buffer, unsigned *ret_nread);
MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int len);
void *mpi_get_buffer(MPI a, unsigned *nbytes, int *sign);
diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index eead4b339466..207cb3b91a51 100644
--- a/lib/mpi/mpicoder.c
+++ b/lib/mpi/mpicoder.c
@@ -78,22 +78,41 @@ MPI mpi_read_raw_data(const void *xbuffer, size_t nbytes)
}
EXPORT_SYMBOL_GPL(mpi_read_raw_data);
-MPI mpi_read_from_buffer(const void *xbuffer, unsigned *ret_nread)
+int mpi_key_length(const void *xbuffer, unsigned int ret_nread,
+ unsigned int *nbits_arg, unsigned int *nbytes_arg)
{
const uint8_t *buffer = xbuffer;
- unsigned int nbits, nbytes;
- MPI val;
+ unsigned int nbits;
- if (*ret_nread < 2)
- return ERR_PTR(-EINVAL);
+ if (ret_nread < 2)
+ return -EINVAL;
nbits = buffer[0] << 8 | buffer[1];
if (nbits > MAX_EXTERN_MPI_BITS) {
pr_info("MPI: mpi too large (%u bits)\n", nbits);
- return ERR_PTR(-EINVAL);
+ return -EINVAL;
}
- nbytes = DIV_ROUND_UP(nbits, 8);
+ if (nbits_arg)
+ *nbits_arg = nbits;
+ if (nbytes_arg)
+ *nbytes_arg = DIV_ROUND_UP(nbits, 8);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mpi_key_length);
+
+MPI mpi_read_from_buffer(const void *xbuffer, unsigned *ret_nread)
+{
+ const uint8_t *buffer = xbuffer;
+ unsigned int nbytes;
+ MPI val;
+ int ret;
+
+ ret = mpi_key_length(xbuffer, *ret_nread, NULL, &nbytes);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
if (nbytes + 2 > *ret_nread) {
pr_info("MPI: mpi larger than buffer nbytes=%u ret_nread=%u\n",
nbytes, *ret_nread);
--
2.17.1
next prev parent reply other threads:[~2018-11-12 10:28 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-12 10:24 [RFC][PATCH 00/12] keys: add support for PGP keys and signatures Roberto Sassu
2018-11-12 10:24 ` Roberto Sassu [this message]
2018-11-12 10:24 ` [RFC][PATCH 02/12] rsa: add parser of raw format Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 03/12] PGPLIB: PGP definitions (RFC 4880) Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 04/12] PGPLIB: Basic packet parser Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 05/12] PGPLIB: Signature parser Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 06/12] KEYS: PGP data parser Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 07/12] KEYS: Provide PGP key description autogeneration Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 08/12] KEYS: PGP-based public key signature verification Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 09/12] verification: introduce verify_pgp_signature() Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 10/12] PGP: Provide a key type for testing PGP signatures Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 11/12] KEYS: Provide a function to load keys from a PGP keyring blob Roberto Sassu
2018-11-12 10:24 ` [RFC][PATCH 12/12] KEYS: Introduce load_pgp_public_keyring() Roberto Sassu
2018-11-12 12:31 ` [RFC][PATCH 04/12] PGPLIB: Basic packet parser David Howells
2018-11-12 12:35 ` [RFC][PATCH 05/12] PGPLIB: Signature parser David Howells
2018-11-12 12:43 ` [RFC][PATCH 08/12] KEYS: PGP-based public key signature verification David Howells
2018-11-12 14:22 ` Roberto Sassu
2018-12-10 16:58 ` David Howells
2018-12-10 18:04 ` Roberto Sassu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20181112102423.30415-2-roberto.sassu@huawei.com \
--to=roberto.sassu@huawei.com \
--cc=davem@davemloft.net \
--cc=dhowells@redhat.com \
--cc=dwmw2@infradead.org \
--cc=herbert@gondor.apana.org.au \
--cc=keyrings@vger.kernel.org \
--cc=linux-crypto@vger.kernel.org \
--cc=linux-integrity@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=silviu.vlasceanu@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).