In rsa_get_n(), if the buffer contained all 0's and "FIPS mode" is
enabled, we would read one byte past the end of the buffer while
scanning the leading zeroes. Fix it by checking 'n_sz' before '!*ptr'.
This bug was reachable by adding a specially crafted key of type
"asymmetric" (requires CONFIG_RSA and CONFIG_X509_CERTIFICATE_PARSER).
KASAN report:
BUG: KASAN: slab-out-of-bounds in rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33
Read of size 1 at addr ffff88003501a708 by task keyctl/196
CPU: 1 PID: 196 Comm: keyctl Not tainted 4.14.0-09238-g1d3b78bbc6e9 #26
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
Call Trace:
rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33
asn1_ber_decoder+0x82a/0x1fd0 lib/asn1_decoder.c:328
rsa_set_pub_key+0xd3/0x320 crypto/rsa.c:278
crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline]
pkcs1pad_set_pub_key+0xae/0x200 crypto/rsa-pkcs1pad.c:117
crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline]
public_key_verify_signature+0x270/0x9d0 crypto/asymmetric_keys/public_key.c:106
x509_check_for_self_signed+0x2ea/0x480 crypto/asymmetric_keys/x509_public_key.c:141
x509_cert_parse+0x46a/0x620 crypto/asymmetric_keys/x509_cert_parser.c:129
x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174
asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388
key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850
SYSC_add_key security/keys/keyctl.c:122 [inline]
SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62
entry_SYSCALL_64_fastpath+0x1f/0x96
Allocated by task 196:
__do_kmalloc mm/slab.c:3711 [inline]
__kmalloc_track_caller+0x118/0x2e0 mm/slab.c:3726
kmemdup+0x17/0x40 mm/util.c:118
kmemdup ./include/linux/string.h:414 [inline]
x509_cert_parse+0x2cb/0x620 crypto/asymmetric_keys/x509_cert_parser.c:106
x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174
asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388
key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850
SYSC_add_key security/keys/keyctl.c:122 [inline]
SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62
entry_SYSCALL_64_fastpath+0x1f/0x96
Fixes: 5a7de97309 ("crypto: rsa - return raw integers for the ASN.1 parser")
Cc: <stable@vger.kernel.org> # v4.8+
Cc: Tudor Ambarus <tudor-dan.ambarus@nxp.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
With a public notification, NIST now allows the use of RSA keys with a
modulus >= 2048 bits. The new rule allows any modulus size >= 2048 bits
provided that either 2048 or 3072 bits are supported at least so that
the entire RSA implementation can be CAVS tested.
This patch fixes the inability to boot the kernel in FIPS mode, because
certs/x509.genkey defines a 4096 bit RSA key per default. This key causes
the RSA signature verification to fail in FIPS mode without the patch
below.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When parsing a private key, store all non-optional fields. These
are required for enabling CRT mode for decrypt and verify
Signed-off-by: Salvatore Benedetto <salvatore.benedetto@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Return the raw key with no other processing so that the caller
can copy it or MPI parse it, etc.
The scope is to have only one ANS.1 parser for all RSA
implementations.
Update the RSA software implementation so that it does
the MPI conversion on top.
Signed-off-by: Tudor Ambarus <tudor-dan.ambarus@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Setkey function has been split into set_priv_key and set_pub_key.
Akcipher requests takes sgl for src and dst instead of void *.
Users of the API i.e. two existing RSA implementation and
test mgr code have been updated accordingly.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The condition checking allowed key length was invalid.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add a new rsa generic SW implementation.
This implements only cryptographic primitives.
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Added select on ASN1.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Eric Biggers