diff options
Diffstat (limited to 'arch/x86/boot')
-rw-r--r-- | arch/x86/boot/compressed/kaslr.c | 76 |
1 files changed, 5 insertions, 71 deletions
diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 010ea16e5f77..a66854d99ee1 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -12,10 +12,6 @@ #include "misc.h" #include "error.h" -#include <asm/msr.h> -#include <asm/archrandom.h> -#include <asm/e820.h> - #include <generated/compile.h> #include <linux/module.h> #include <linux/uts.h> @@ -26,26 +22,6 @@ static const char build_str[] = UTS_RELEASE " (" LINUX_COMPILE_BY "@" LINUX_COMPILE_HOST ") (" LINUX_COMPILER ") " UTS_VERSION; -#define I8254_PORT_CONTROL 0x43 -#define I8254_PORT_COUNTER0 0x40 -#define I8254_CMD_READBACK 0xC0 -#define I8254_SELECT_COUNTER0 0x02 -#define I8254_STATUS_NOTREADY 0x40 -static inline u16 i8254(void) -{ - u16 status, timer; - - do { - outb(I8254_PORT_CONTROL, - I8254_CMD_READBACK | I8254_SELECT_COUNTER0); - status = inb(I8254_PORT_COUNTER0); - timer = inb(I8254_PORT_COUNTER0); - timer |= inb(I8254_PORT_COUNTER0) << 8; - } while (status & I8254_STATUS_NOTREADY); - - return timer; -} - static unsigned long rotate_xor(unsigned long hash, const void *area, size_t size) { @@ -62,7 +38,7 @@ static unsigned long rotate_xor(unsigned long hash, const void *area, } /* Attempt to create a simple but unpredictable starting entropy. */ -static unsigned long get_random_boot(void) +static unsigned long get_boot_seed(void) { unsigned long hash = 0; @@ -72,50 +48,8 @@ static unsigned long get_random_boot(void) return hash; } -static unsigned long get_random_long(const char *purpose) -{ -#ifdef CONFIG_X86_64 - const unsigned long mix_const = 0x5d6008cbf3848dd3UL; -#else - const unsigned long mix_const = 0x3f39e593UL; -#endif - unsigned long raw, random = get_random_boot(); - bool use_i8254 = true; - - debug_putstr(purpose); - debug_putstr(" KASLR using"); - - if (has_cpuflag(X86_FEATURE_RDRAND)) { - debug_putstr(" RDRAND"); - if (rdrand_long(&raw)) { - random ^= raw; - use_i8254 = false; - } - } - - if (has_cpuflag(X86_FEATURE_TSC)) { - debug_putstr(" RDTSC"); - raw = rdtsc(); - - random ^= raw; - use_i8254 = false; - } - - if (use_i8254) { - debug_putstr(" i8254"); - random ^= i8254(); - } - - /* Circular multiply for better bit diffusion */ - asm("mul %3" - : "=a" (random), "=d" (raw) - : "a" (random), "rm" (mix_const)); - random += raw; - - debug_putstr("...\n"); - - return random; -} +#define KASLR_COMPRESSED_BOOT +#include "../../lib/kaslr.c" struct mem_vector { unsigned long start; @@ -349,7 +283,7 @@ static unsigned long slots_fetch_random(void) if (slot_max == 0) return 0; - slot = get_random_long("Physical") % slot_max; + slot = kaslr_get_random_long("Physical") % slot_max; for (i = 0; i < slot_area_index; i++) { if (slot >= slot_areas[i].num) { @@ -479,7 +413,7 @@ static unsigned long find_random_virt_addr(unsigned long minimum, slots = (KERNEL_IMAGE_SIZE - minimum - image_size) / CONFIG_PHYSICAL_ALIGN + 1; - random_addr = get_random_long("Virtual") % slots; + random_addr = kaslr_get_random_long("Virtual") % slots; return random_addr * CONFIG_PHYSICAL_ALIGN + minimum; } |