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* crypto: jitter - update implementation to 2.1.2Stephan Müller2019-06-061-223/+82
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Jitter RNG implementation is updated to comply with upstream version 2.1.2. The change covers the following aspects: * Time variation measurement is conducted over the LFSR operation instead of the XOR folding * Invcation of stuck test during initialization * Removal of the stirring functionality and the Von-Neumann unbiaser as the LFSR using a primitive and irreducible polynomial generates an identical distribution of random bits This implementation was successfully used in FIPS 140-2 validations as well as in German BSI evaluations. This kernel implementation was tested as follows: * The unchanged kernel code file jitterentropy.c is compiled as part of user space application to generate raw unconditioned noise data. That data is processed with the NIST SP800-90B non-IID test tool to verify that the kernel code exhibits an equal amount of noise as the upstream Jitter RNG version 2.1.2. * Using AF_ALG with the libkcapi tool of kcapi-rng the Jitter RNG was output tested with dieharder to verify that the output does not exhibit statistical weaknesses. The following command was used: kcapi-rng -n "jitterentropy_rng" -b 100000000000 | dieharder -a -g 200 * The unchanged kernel code file jitterentropy.c is compiled as part of user space application to test the LFSR implementation. The LFSR is injected a monotonically increasing counter as input and the output is fed into dieharder to verify that the LFSR operation does not exhibit statistical weaknesses. * The patch was tested on the Muen separation kernel which returns a more coarse time stamp to verify that the Jitter RNG does not cause regressions with its initialization test considering that the Jitter RNG depends on a high-resolution timer. Tested-by: Reto Buerki <reet@codelabs.ch> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: jitterentropy - Delete unnecessary checks before the function call ↵Markus Elfring2015-06-251-4/+2
| | | | | | | | | | | | "kzfree" The kzfree() function tests whether its argument is NULL and then returns immediately. Thus the test around the call is not needed. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: jitterentropy - avoid compiler warningsStephan Mueller2015-06-251-176/+37
| | | | | | | | | | | | | | | | The core of the Jitter RNG is intended to be compiled with -O0. To ensure that the Jitter RNG can be compiled on all architectures, separate out the RNG core into a stand-alone C file that can be compiled with -O0 which does not depend on any kernel include file. As no kernel includes can be used in the C file implementing the core RNG, any dependencies on kernel code must be extracted. A second file provides the link to the kernel and the kernel crypto API that can be compiled with the regular compile options of the kernel. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: drbg - use pragmas for disabling optimizationStephan Mueller2015-06-091-4/+26
| | | | | | | | | | | | Replace the global -O0 compiler flag from the Makefile with GCC pragmas to mark only the functions required to be compiled without optimizations. This patch also adds a comment describing the rationale for the functions chosen to be compiled without optimizations. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: jitterentropy - remove timekeeping_valid_for_hresStephan Mueller2015-05-281-3/+0
| | | | | | | | | | | | | The patch removes the use of timekeeping_valid_for_hres which is now marked as internal for the time keeping subsystem. The jitterentropy does not really require this verification as a coarse timer (when random_get_entropy is absent) is discovered by the initialization test of jent_entropy_init, which would cause the jitter rng to not load in that case. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* crypto: jitterentropy - add jitterentropy RNGStephan Mueller2015-05-271-0/+909
The CPU Jitter RNG provides a source of good entropy by collecting CPU executing time jitter. The entropy in the CPU execution time jitter is magnified by the CPU Jitter Random Number Generator. The CPU Jitter Random Number Generator uses the CPU execution timing jitter to generate a bit stream which complies with different statistical measurements that determine the bit stream is random. The CPU Jitter Random Number Generator delivers entropy which follows information theoretical requirements. Based on these studies and the implementation, the caller can assume that one bit of data extracted from the CPU Jitter Random Number Generator holds one bit of entropy. The CPU Jitter Random Number Generator provides a decentralized source of entropy, i.e. every caller can operate on a private state of the entropy pool. The RNG does not have any dependencies on any other service in the kernel. The RNG only needs a high-resolution time stamp. Further design details, the cryptographic assessment and large array of test results are documented at http://www.chronox.de/jent.html. CC: Andreas Steffen <andreas.steffen@strongswan.org> CC: Theodore Ts'o <tytso@mit.edu> CC: Sandy Harris <sandyinchina@gmail.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>