Merge remote-tracking branch 'security/next'
crypto: authencesn - Simplify key parsing Use the common helper function crypto_authenc_extractkeys() for key parsing. Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Mathias Krause <mathias.krause@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto: authenc - Export key parsing helper function AEAD key parsing is duplicated to multiple places in the kernel. Add a common helper function to consolidate that functionality. Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Mathias Krause <mathias.krause@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto: crypto_memneq - add equality testing of memory regions w/o timing leaks When comparing MAC hashes, AEAD authentication tags, or other hash values in the context of authentication or integrity checking, it is important not to leak timing information to a potential attacker, i.e. when communication happens over a network. Bytewise memory comparisons (such as memcmp) are usually optimized so that they return a nonzero value as soon as a mismatch is found. E.g, on x86_64/i5 for 512 bytes this can be ~50 cyc for a full mismatch and up to ~850 cyc for a full match (cold). This early-return behavior can leak timing information as a side channel, allowing an attacker to iteratively guess the correct result. This patch adds a new method crypto_memneq ("memory not equal to each other") to the crypto API that compares memory areas of the same length in roughly "constant time" (cache misses could change the timing, but since they don't reveal information about the content of the strings being compared, they are effectively benign). Iow, best and worst case behaviour take the same amount of time to complete (in contrast to memcmp). Note that crypto_memneq (unlike memcmp) can only be used to test for equality or inequality, NOT for lexicographical order. This, however, is not an issue for its use-cases within the crypto API. We tried to locate all of the places in the crypto API where memcmp was being used for authentication or integrity checking, and convert them over to crypto_memneq. crypto_memneq is declared noinline, placed in its own source file, and compiled with optimizations that might increase code size disabled ("Os") because a smart compiler (or LTO) might notice that the return value is always compared against zero/nonzero, and might then reintroduce the same early-return optimization that we are trying to avoid. Using #pragma or __attribute__ optimization annotations of the code for disabling optimization was avoided as it seems to be considered broken or unmaintained for long time in GCC [1]. Therefore, we work around that by specifying the compile flag for memneq.o directly in the Makefile. We found that this seems to be most appropriate. As we use ("Os"), this patch also provides a loop-free "fast-path" for frequently used 16 byte digests. Similarly to kernel library string functions, leave an option for future even further optimized architecture specific assembler implementations. This was a joint work of James Yonan and Daniel Borkmann. Also thanks for feedback from Florian Weimer on this and earlier proposals [2]. [1] http://gcc.gnu.org/ml/gcc/2012-07/msg00211.html [2] https://lkml.org/lkml/2013/2/10/131 Signed-off-by: James Yonan <james@openvpn.net> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Florian Weimer <fw@deneb.enyo.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto: ablk_helper - Replace memcpy with struct assignment tree: git://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master head: 48e6dc1b2a1ad8186d48968d5018912bdacac744 commit: a62b01cd6cc1feb5e80d64d6937c291473ed82cb [20/24] crypto: create generic version of ablk_helper coccinelle warnings: (new ones prefixed by >>) >> crypto/ablk_helper.c:97:2-8: Replace memcpy with struct assignment >> crypto/ablk_helper.c:78:2-8: Replace memcpy with struct assignment Please consider folding the attached diff :-) Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ARM: add support for bit sliced AES using NEON instructions Bit sliced AES gives around 45% speedup on Cortex-A15 for encryption and around 25% for decryption. This implementation of the AES algorithm does not rely on any lookup tables so it is believed to be invulnerable to cache timing attacks. This algorithm processes up to 8 blocks in parallel in constant time. This means that it is not usable by chaining modes that are strictly sequential in nature, such as CBC encryption. CBC decryption, however, can benefit from this implementation and runs about 25% faster. The other chaining modes implemented in this module, XTS and CTR, can execute fully in parallel in both directions. The core code has been adopted from the OpenSSL project (in collaboration with the original author, on cc). For ease of maintenance, this version is identical to the upstream OpenSSL code, i.e., all modifications that were required to make it suitable for inclusion into the kernel have been made upstream. The original can be found here: http://git.openssl.org/gitweb/?p=openssl.git;a=commit;h=6f6a6130 Note to integrators: While this implementation is significantly faster than the existing table based ones (generic or ARM asm), especially in CTR mode, the effects on power efficiency are unclear as of yet. This code does fundamentally more work, by calculating values that the table based code obtains by a simple lookup; only by doing all of that work in a SIMD fashion, it manages to perform better. Cc: Andy Polyakov <appro@openssl.org> Acked-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
KEYS: verify a certificate is signed by a 'trusted' key Only public keys, with certificates signed by an existing 'trusted' key on the system trusted keyring, should be added to a trusted keyring. This patch adds support for verifying a certificate's signature. This is derived from David Howells pkcs7_request_asymmetric_key() patch. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Signed-off-by: David Howells <dhowells@redhat.com>
KEYS: Set the asymmetric-key type default search method The keyring expansion patches introduces a new search method by which key_search() attempts to walk directly to the key that has exactly the same description as the requested one. However, this causes inexact matching of asymmetric keys to fail. The solution to this is to select iterative rather than direct search as the default search type for asymmetric keys. As an example, the kernel might have a key like this: Magrathea: Glacier signing key: 6a2a0f82bad7e396665f465e4e3e1f9bd24b1226 and: keyctl search <keyring-ID> asymmetric id:d24b1226 should find the key, despite that not being its exact description. Signed-off-by: David Howells <dhowells@redhat.com>
X.509: Remove certificate date checks Remove the certificate date checks that are performed when a certificate is parsed. There are two checks: a valid from and a valid to. The first check is causing a lot of problems with system clocks that don't keep good time and the second places an implicit expiry date upon the kernel when used for module signing, so do we really need them? Signed-off-by: David Howells <dhowells@redhat.com> cc: David Woodhouse <dwmw2@infradead.org> cc: Rusty Russell <rusty@rustcorp.com.au> cc: Josh Boyer <jwboyer@redhat.com> cc: Alexander Holler <holler@ahsoftware.de> cc: stable@vger.kernel.org
X.509: Handle certificates that lack an authorityKeyIdentifier field Handle certificates that lack an authorityKeyIdentifier field by assuming they're self-signed and checking their signatures against themselves. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Josh Boyer <jwboyer@redhat.com>
X.509: Check the algorithm IDs obtained from parsing an X.509 certificate Check that the algorithm IDs obtained from the ASN.1 parse by OID lookup corresponds to algorithms that are available to us. Reported-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Howells <dhowells@redhat.com>
X.509: Embed public_key_signature struct and create filler function Embed a public_key_signature struct in struct x509_certificate, eliminating now unnecessary fields, and split x509_check_signature() to create a filler function for it that attaches a digest of the signed data and an MPI that represents the signature data. x509_free_certificate() is then modified to deal with these. Whilst we're at it, export both x509_check_signature() and the new x509_get_sig_params(). Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Josh Boyer <jwboyer@redhat.com>
X.509: struct x509_certificate needs struct tm declaring struct x509_certificate needs struct tm declaring by #inclusion of linux/time.h prior to its definition. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Josh Boyer <jwboyer@redhat.com>
KEYS: Split public_key_verify_signature() and make available Modify public_key_verify_signature() so that it now takes a public_key struct rather than a key struct and supply a wrapper that takes a key struct. The wrapper is then used by the asymmetric key subtype and the modified function is used by X.509 self-signature checking and can be used by other things also. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Josh Boyer <jwboyer@redhat.com>
KEYS: Store public key algo ID in public_key struct Store public key algo ID in public_key struct for reference purposes. This allows it to be removed from the x509_certificate struct and used to find a default in public_key_verify_signature(). Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Josh Boyer <jwboyer@redhat.com>
KEYS: Move the algorithm pointer array from x509 to public_key.c Move the public-key algorithm pointer array from x509_public_key.c to public_key.c as it isn't X.509 specific. Note that to make this configure correctly, the public key part must be dependent on the RSA module rather than the other way round. This needs a further patch to make use of the crypto module loading stuff rather than using a fixed table. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Josh Boyer <jwboyer@redhat.com>