Commit Graph

9 Commits

Author SHA1 Message Date
Lukas Wunner
4b6beff3c0 crypto: ecdsa - Avoid signed integer overflow on signature decoding
[ Upstream commit 3b0565c703 ]

When extracting a signature component r or s from an ASN.1-encoded
integer, ecdsa_get_signature_rs() subtracts the expected length
"bufsize" from the ASN.1 length "vlen" (both of unsigned type size_t)
and stores the result in "diff" (of signed type ssize_t).

This results in a signed integer overflow if vlen > SSIZE_MAX + bufsize.

The kernel is compiled with -fno-strict-overflow, which implies -fwrapv,
meaning signed integer overflow is not undefined behavior.  And the
function does check for overflow:

       if (-diff >= bufsize)
               return -EINVAL;

So the code is fine in principle but not very obvious.  In the future it
might trigger a false-positive with CONFIG_UBSAN_SIGNED_WRAP=y.

Avoid by comparing the two unsigned variables directly and erroring out
if "vlen" is too large.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-09 13:31:41 +01:00
Stefan Berger
ec64889179 crypto: ecdsa - Use ecc_digits_from_bytes to convert signature
[ Upstream commit 546ce0bdc9 ]

Since ecc_digits_from_bytes will provide zeros when an insufficient number
of bytes are passed in the input byte array, use it to convert the r and s
components of the signature to digits directly from the input byte
array. This avoids going through an intermediate byte array that has the
first few bytes filled with zeros.

Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stable-dep-of: 3b0565c703 ("crypto: ecdsa - Avoid signed integer overflow on signature decoding")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-09 13:31:41 +01:00
Stefan Berger
1afc7acbed crypto: ecdsa - Rename keylen to bufsize where necessary
[ Upstream commit 703ca5cda1 ]

In cases where 'keylen' was referring to the size of the buffer used by
a curve's digits, it does not reflect the purpose of the variable anymore
once NIST P521 is used. What it refers to then is the size of the buffer,
which may be a few bytes larger than the size a coordinate of a key.
Therefore, rename keylen to bufsize where appropriate.

Tested-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stable-dep-of: 3b0565c703 ("crypto: ecdsa - Avoid signed integer overflow on signature decoding")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-09 13:31:40 +01:00
Stefan Berger
e7fcd5d696 crypto: ecdsa - Convert byte arrays with key coordinates to digits
[ Upstream commit d67c96fb97 ]

For NIST P192/256/384 the public key's x and y parameters could be copied
directly from a given array since both parameters filled 'ndigits' of
digits (a 'digit' is a u64). For support of NIST P521 the key parameters
need to have leading zeros prepended to the most significant digit since
only 2 bytes of the most significant digit are provided.

Therefore, implement ecc_digits_from_bytes to convert a byte array into an
array of digits and use this function in ecdsa_set_pub_key where an input
byte array needs to be converted into digits.

Suggested-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stable-dep-of: 3b0565c703 ("crypto: ecdsa - Avoid signed integer overflow on signature decoding")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-01-09 13:31:40 +01:00
Stefan Berger
cc3306fb04 crypto: ecdsa - Fix module auto-load on add-key
commit 48e4fd6d54 upstream.

Add module alias with the algorithm cra_name similar to what we have for
RSA-related and other algorithms.

The kernel attempts to modprobe asymmetric algorithms using the names
"crypto-$cra_name" and "crypto-$cra_name-all." However, since these
aliases are currently missing, the modules are not loaded. For instance,
when using the `add_key` function, the hash algorithm is typically
loaded automatically, but the asymmetric algorithm is not.

Steps to test:

1. Create certificate

  openssl req -x509 -sha256 -newkey ec \
  -pkeyopt "ec_paramgen_curve:secp384r1" -keyout key.pem -days 365 \
  -subj '/CN=test' -nodes -outform der -out nist-p384.der

2. Optionally, trace module requests with: trace-cmd stream -e module &

3. Trigger add_key call for the cert:

   # keyctl padd asymmetric "" @u < nist-p384.der
   641069229
   # lsmod | head -2
   Module                  Size  Used by
   ecdsa_generic          16384  0

Fixes: c12d448ba9 ("crypto: ecdsa - Register NIST P384 and extend test suite")
Cc: stable@vger.kernel.org
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-06-16 13:47:39 +02:00
Xiu Jianfeng
33837be333 crypto: add __init/__exit annotations to init/exit funcs
Add missing __init/__exit annotations to init/exit funcs.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2022-09-24 16:14:43 +08:00
Daniele Alessandrelli
a745d3ace3 crypto: ecc - Move ecc.h to include/crypto/internal
Move ecc.h header file to 'include/crypto/internal' so that it can be
easily imported from everywhere in the kernel tree.

This change is done to allow crypto device drivers to re-use the symbols
exported by 'crypto/ecc.c', thus avoiding code duplication.

Signed-off-by: Daniele Alessandrelli <daniele.alessandrelli@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-10-29 21:04:03 +08:00
Saulo Alessandre
c12d448ba9 crypto: ecdsa - Register NIST P384 and extend test suite
Register NIST P384 as an akcipher and extend the testmgr with
NIST P384-specific test vectors.

Summary of changes:

* crypto/ecdsa.c
  - add ecdsa_nist_p384_init_tfm
  - register and unregister P384 tfm

* crypto/testmgr.c
  - add test vector for P384 on vector of tests

* crypto/testmgr.h
  - add test vector params for P384(sha1, sha224, sha256, sha384
    and sha512)

Signed-off-by: Saulo Alessandre <saulo.alessandre@tse.jus.br>
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-03-26 19:41:58 +11:00
Stefan Berger
4e6602916b crypto: ecdsa - Add support for ECDSA signature verification
Add support for parsing the parameters of a NIST P256 or NIST P192 key.
Enable signature verification using these keys. The new module is
enabled with CONFIG_ECDSA:
  Elliptic Curve Digital Signature Algorithm (NIST P192, P256 etc.)
  is A NIST cryptographic standard algorithm. Only signature verification
  is implemented.

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-03-26 19:41:58 +11:00