diff options
Diffstat (limited to 'src/arch')
| -rw-r--r-- | src/arch/arm/include/bits/entropy.h | 12 | ||||
| -rw-r--r-- | src/arch/loong64/include/bits/entropy.h | 12 | ||||
| -rw-r--r-- | src/arch/x86/core/rdrand.c | 32 | ||||
| -rw-r--r-- | src/arch/x86/include/bits/entropy.h | 15 | ||||
| -rw-r--r-- | src/arch/x86/include/ipxe/rdrand.h | 37 | ||||
| -rw-r--r-- | src/arch/x86/include/ipxe/rtc_entropy.h | 62 | ||||
| -rw-r--r-- | src/arch/x86/interface/pcbios/rtc_entropy.c | 38 |
7 files changed, 48 insertions, 160 deletions
diff --git a/src/arch/arm/include/bits/entropy.h b/src/arch/arm/include/bits/entropy.h deleted file mode 100644 index 75fdc90ea..000000000 --- a/src/arch/arm/include/bits/entropy.h +++ /dev/null @@ -1,12 +0,0 @@ -#ifndef _BITS_ENTROPY_H -#define _BITS_ENTROPY_H - -/** @file - * - * ARM-specific entropy API implementations - * - */ - -FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); - -#endif /* _BITS_ENTROPY_H */ diff --git a/src/arch/loong64/include/bits/entropy.h b/src/arch/loong64/include/bits/entropy.h deleted file mode 100644 index 8d3726930..000000000 --- a/src/arch/loong64/include/bits/entropy.h +++ /dev/null @@ -1,12 +0,0 @@ -#ifndef _BITS_ENTROPY_H -#define _BITS_ENTROPY_H - -/** @file - * - * LoongArch64-specific entropy API implementations - * - */ - -FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); - -#endif /* _BITS_ENTROPY_H */ diff --git a/src/arch/x86/core/rdrand.c b/src/arch/x86/core/rdrand.c index 29605ab2f..850ab1f11 100644 --- a/src/arch/x86/core/rdrand.c +++ b/src/arch/x86/core/rdrand.c @@ -32,12 +32,15 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); #include <errno.h> #include <ipxe/cpuid.h> #include <ipxe/entropy.h> +#include <ipxe/drbg.h> + +struct entropy_source rdrand_entropy __entropy_source ( ENTROPY_PREFERRED ); /** Number of times to retry RDRAND instruction */ #define RDRAND_RETRY_COUNT 16 /** Colour for debug messages */ -#define colour CPUID_FEATURES_INTEL_ECX_RDRAND +#define colour &rdrand_entropy /** * Enable entropy gathering @@ -54,16 +57,15 @@ static int rdrand_entropy_enable ( void ) { return -ENOTSUP; } - return 0; -} - -/** - * Disable entropy gathering - * - */ -static void rdrand_entropy_disable ( void ) { + /* Data returned by RDRAND is theoretically full entropy, up + * to a security strength of 128 bits, so assume that each + * sample contains exactly 8 bits of entropy. + */ + if ( DRBG_SECURITY_STRENGTH > 128 ) + return -ENOTSUP; + entropy_init ( &rdrand_entropy, MIN_ENTROPY ( 8.0 ) ); - /* Nothing to do */ + return 0; } /** @@ -93,7 +95,9 @@ static int rdrand_get_noise ( noise_sample_t *noise ) { return 0; } -PROVIDE_ENTROPY_INLINE ( rdrand, min_entropy_per_sample ); -PROVIDE_ENTROPY ( rdrand, entropy_enable, rdrand_entropy_enable ); -PROVIDE_ENTROPY ( rdrand, entropy_disable, rdrand_entropy_disable ); -PROVIDE_ENTROPY ( rdrand, get_noise, rdrand_get_noise ); +/** Hardware random number generator entropy source */ +struct entropy_source rdrand_entropy __entropy_source ( ENTROPY_PREFERRED ) = { + .name = "rdrand", + .enable = rdrand_entropy_enable, + .get_noise = rdrand_get_noise, +}; diff --git a/src/arch/x86/include/bits/entropy.h b/src/arch/x86/include/bits/entropy.h deleted file mode 100644 index 7accea33f..000000000 --- a/src/arch/x86/include/bits/entropy.h +++ /dev/null @@ -1,15 +0,0 @@ -#ifndef _BITS_ENTROPY_H -#define _BITS_ENTROPY_H - -/** @file - * - * x86-specific entropy API implementations - * - */ - -FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); - -#include <ipxe/rtc_entropy.h> -#include <ipxe/rdrand.h> - -#endif /* _BITS_ENTROPY_H */ diff --git a/src/arch/x86/include/ipxe/rdrand.h b/src/arch/x86/include/ipxe/rdrand.h deleted file mode 100644 index c9c170fb0..000000000 --- a/src/arch/x86/include/ipxe/rdrand.h +++ /dev/null @@ -1,37 +0,0 @@ -#ifndef _IPXE_RDRAND_H -#define _IPXE_RDRAND_H - -/** @file - * - * Hardware random number generator - * - */ - -FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); - -#include <stdint.h> -#include <ipxe/drbg.h> - -#ifdef ENTROPY_RDRAND -#define ENTROPY_PREFIX_rdrand -#else -#define ENTROPY_PREFIX_rdrand __rdrand_ -#endif - -/** - * min-entropy per sample - * - * @ret min_entropy min-entropy of each sample - */ -static inline __always_inline min_entropy_t -ENTROPY_INLINE ( rdrand, min_entropy_per_sample ) ( void ) { - - /* Data returned by RDRAND is theoretically full entropy, up - * to a security strength of 128 bits. - */ - if ( DRBG_SECURITY_STRENGTH > 128 ) - return 0; - return MIN_ENTROPY ( 8 * sizeof ( noise_sample_t ) ); -} - -#endif /* _IPXE_RDRAND_H */ diff --git a/src/arch/x86/include/ipxe/rtc_entropy.h b/src/arch/x86/include/ipxe/rtc_entropy.h deleted file mode 100644 index 581abcd3e..000000000 --- a/src/arch/x86/include/ipxe/rtc_entropy.h +++ /dev/null @@ -1,62 +0,0 @@ -#ifndef _IPXE_RTC_ENTROPY_H -#define _IPXE_RTC_ENTROPY_H - -/** @file - * - * RTC-based entropy source - * - */ - -FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); - -#include <stdint.h> - -#ifdef ENTROPY_RTC -#define ENTROPY_PREFIX_rtc -#else -#define ENTROPY_PREFIX_rtc __rtc_ -#endif - -/** - * min-entropy per sample - * - * @ret min_entropy min-entropy of each sample - */ -static inline __always_inline min_entropy_t -ENTROPY_INLINE ( rtc, min_entropy_per_sample ) ( void ) { - - /* The min-entropy has been measured on several platforms - * using the entropy_sample test code. Modelling the samples - * as independent, and using a confidence level of 99.99%, the - * measurements were as follows: - * - * qemu-kvm : 7.38 bits - * VMware : 7.46 bits - * Physical hardware : 2.67 bits - * - * We choose the lowest of these (2.67 bits) and apply a 50% - * safety margin to allow for some potential non-independence - * of samples. - */ - return MIN_ENTROPY ( 1.3 ); -} - -extern uint8_t rtc_sample ( void ); - -/** - * Get noise sample - * - * @ret noise Noise sample - * @ret rc Return status code - */ -static inline __always_inline int -ENTROPY_INLINE ( rtc, get_noise ) ( noise_sample_t *noise ) { - - /* Get sample */ - *noise = rtc_sample(); - - /* Always successful */ - return 0; -} - -#endif /* _IPXE_RTC_ENTROPY_H */ diff --git a/src/arch/x86/interface/pcbios/rtc_entropy.c b/src/arch/x86/interface/pcbios/rtc_entropy.c index c400d8a78..8f47ff6b8 100644 --- a/src/arch/x86/interface/pcbios/rtc_entropy.c +++ b/src/arch/x86/interface/pcbios/rtc_entropy.c @@ -39,6 +39,8 @@ FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); #include <ipxe/cpuid.h> #include <ipxe/entropy.h> +struct entropy_source rtc_entropy __entropy_source ( ENTROPY_NORMAL ); + /** Maximum time to wait for an RTC interrupt, in milliseconds */ #define RTC_MAX_WAIT_MS 100 @@ -203,6 +205,21 @@ static int rtc_entropy_enable ( void ) { if ( ( rc = rtc_entropy_check() ) != 0 ) goto err_check; + /* The min-entropy has been measured on several platforms + * using the entropy_sample test code. Modelling the samples + * as independent, and using a confidence level of 99.99%, the + * measurements were as follows: + * + * qemu-kvm : 7.38 bits + * VMware : 7.46 bits + * Physical hardware : 2.67 bits + * + * We choose the lowest of these (2.67 bits) and apply a 50% + * safety margin to allow for some potential non-independence + * of samples. + */ + entropy_init ( &rtc_entropy, MIN_ENTROPY ( 1.3 ) ); + return 0; err_check: @@ -226,11 +243,12 @@ static void rtc_entropy_disable ( void ) { } /** - * Measure a single RTC tick + * Get noise sample * - * @ret delta Length of RTC tick (in TSC units) + * @ret noise Noise sample + * @ret rc Return status code */ -uint8_t rtc_sample ( void ) { +static int rtc_get_noise ( noise_sample_t *noise ) { uint32_t before; uint32_t after; uint32_t temp; @@ -265,10 +283,14 @@ uint8_t rtc_sample ( void ) { : "=a" ( after ), "=d" ( before ), "=Q" ( temp ) : "2" ( 0 ) ); - return ( after - before ); + *noise = ( after - before ); + return 0; } -PROVIDE_ENTROPY_INLINE ( rtc, min_entropy_per_sample ); -PROVIDE_ENTROPY ( rtc, entropy_enable, rtc_entropy_enable ); -PROVIDE_ENTROPY ( rtc, entropy_disable, rtc_entropy_disable ); -PROVIDE_ENTROPY_INLINE ( rtc, get_noise ); +/** RTC entropy source */ +struct entropy_source rtc_entropy __entropy_source ( ENTROPY_NORMAL ) = { + .name = "rtc", + .enable = rtc_entropy_enable, + .disable = rtc_entropy_disable, + .get_noise = rtc_get_noise, +}; |