Hi Herbert, Ted, The following patch set provides a different approach to /dev/random which I call Linux Random Number Generator (LRNG) to collect entropy within the Linux kernel. The main improvements compared to the legacy /dev/random is to provide sufficient entropy during boot time as well as in virtual environments and when using SSDs. A secondary design goal is to limit the impact of the entropy collection on massive parallel systems and also allow the use accelerated cryptographic primitives. Also, all steps of the entropic data processing are testable. Finally massive performance improvements are visible at /dev/urandom and get_random_bytes.
The design and implementation is driven by a set of goals described in [1] that the LRNG completely implements. Furthermore, [1] includes a comparison with RNG design suggestions such as SP800-90B, SP800-90C, and AIS20/31. Changes v2: * Removal of the Jitter RNG fast noise source as requested by Ted * Addition of processing of add_input_randomness as suggested by Ted * Update documentation and testing in [1] to cover the updates * Addition of a SystemTap script to test add_input_randomness * To clarify the question whether sufficient entropy is present during boot I added one more test in 3.3.1 [1] which demonstrates the providing of sufficient entropy during initialization. In the worst case of no fast noise sources, in the worst case of a virtual machine with only very few hardware devices, the testing shows that the secondary DRBG is fully seeded with 256 bits of entropy before user space injects the random data obtained during shutdown of the previous boot (i.e. the requirement phrased by the legacy /dev/random implementation). As the writing of the random data into /dev/random by user space will happen before any cryptographic service is initialized in user space, this test demonstrates that sufficient entropy is already present in the LRNG at the time user space requires it for seeding cryptographic daemons. Note, this test result was obtained for different architectures, such as x86 64 bit, x86 32 bit, ARM 32 bit and MIPS 32 bit. [1] http://www.chronox.de/lrng/doc/lrng.pdf [2] http://www.chronox.de/lrng.html Stephan Mueller (6): crypto: DRBG - externalize DRBG functions for LRNG random: conditionally compile code depending on LRNG crypto: Linux Random Number Generator crypto: LRNG - enable compile crypto: LRNG - hook LRNG into interrupt handler hyperv IRQ handler: trigger LRNG crypto/Kconfig | 10 + crypto/Makefile | 1 + crypto/drbg.c | 11 +- crypto/lrng.c | 1743 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/char/random.c | 8 + drivers/hv/vmbus_drv.c | 3 + include/crypto/drbg.h | 7 + include/linux/genhd.h | 5 + include/linux/random.h | 9 +- kernel/irq/handle.c | 1 + 10 files changed, 1791 insertions(+), 7 deletions(-) create mode 100644 crypto/lrng.c -- 2.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
