From 09ac5d87d11aa0b1fa0e0a4184ab03b3671a73e2 Mon Sep 17 00:00:00 2001 From: Werner Koch Date: Fri, 21 Dec 2012 17:26:06 +0100 Subject: Prepare for hardware feature detection on other platforms. * configure.ac (GCRYPT_HWF_MODULES): New. (HAVE_CPU_ARCH_X86, HAVE_CPU_ARCH_ALPHA, HAVE_CPU_ARCH_SPARC) (HAVE_CPU_ARCH_MIPS, HAVE_CPU_ARCH_M68K, HAVE_CPU_ARCH_PPC) (HAVE_CPU_ARCH_ARM): New AC_DEFINEs. * mpi/config.links (mpi_cpu_arch): New. * src/global.c (print_config): Print new tag "cpu-arch". * src/Makefile.am (libgcrypt_la_SOURCES): Add hwf-common.h (EXTRA_libgcrypt_la_SOURCES): New. (gcrypt_hwf_modules): New. (libgcrypt_la_DEPENDENCIES, libgcrypt_la_LIBADD): Add that one. * src/hwfeatures.c: Factor most code out to ... * src/hwf-x86.c: New file. (detect_x86_gnuc): Return the feature vector. (_gcry_hwf_detect_x86): New. * src/hwf-common.h: New. * src/hwfeatures.c (_gcry_detect_hw_features): Dispatch using HAVE_CPU_ARCH_ macros. Signed-off-by: Werner Koch --- src/hwf-x86.c | 226 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 226 insertions(+) create mode 100644 src/hwf-x86.c (limited to 'src/hwf-x86.c') diff --git a/src/hwf-x86.c b/src/hwf-x86.c new file mode 100644 index 00000000..b50b4b02 --- /dev/null +++ b/src/hwf-x86.c @@ -0,0 +1,226 @@ +/* hwf-x86.c - Detect hardware features - x86 part + * Copyright (C) 2007, 2011, 2012 Free Software Foundation, Inc. + * Copyright (C) 2012 Jussi Kivilinna + * + * This file is part of Libgcrypt. + * + * Libgcrypt is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * Libgcrypt is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this program; if not, see . + */ + +#include +#include +#include +#include +#include +#include + +#include "g10lib.h" +#include "hwf-common.h" + +#if !defined (__i386__) && !defined (__x86_64__) +# error Module build for wrong CPU. +#endif + +/* We use the next macro to decide whether we can test for certain + features. */ +#undef HAS_X86_CPUID + +#if defined (__i386__) && SIZEOF_UNSIGNED_LONG == 4 && defined (__GNUC__) +# define HAS_X86_CPUID 1 + +static int +is_cpuid_available(void) +{ + int has_cpuid = 0; + + /* Detect the CPUID feature by testing some undefined behaviour (16 + vs 32 bit pushf/popf). */ + asm volatile + ("pushf\n\t" /* Copy flags to EAX. */ + "popl %%eax\n\t" + "movl %%eax, %%ecx\n\t" /* Save flags into ECX. */ + "xorl $0x200000, %%eax\n\t" /* Toggle ID bit and copy it to the flags. */ + "pushl %%eax\n\t" + "popf\n\t" + "pushf\n\t" /* Copy changed flags again to EAX. */ + "popl %%eax\n\t" + "pushl %%ecx\n\t" /* Restore flags from ECX. */ + "popf\n\t" + "xorl %%eax, %%ecx\n\t" /* Compare flags against saved flags. */ + "jz .Lno_cpuid%=\n\t" /* Toggling did not work, thus no CPUID. */ + "movl $1, %0\n" /* Worked. true -> HAS_CPUID. */ + ".Lno_cpuid%=:\n\t" + : "+r" (has_cpuid) + : + : "%eax", "%ecx", "cc" + ); + + return has_cpuid; +} + +static void +get_cpuid(unsigned int in, unsigned int *eax, unsigned int *ebx, + unsigned int *ecx, unsigned int *edx) +{ + unsigned int regs[4]; + + asm volatile + ("pushl %%ebx\n\t" /* Save GOT register. */ + "cpuid\n\t" + "movl %%ebx, %1\n\t" + "popl %%ebx\n\t" /* Restore GOT register. */ + : "=a" (regs[0]), "=r" (regs[1]), "=c" (regs[2]), "=d" (regs[3]) + : "0" (in) + : "cc" + ); + + if (eax) + *eax = regs[0]; + if (ebx) + *ebx = regs[1]; + if (ecx) + *ecx = regs[2]; + if (edx) + *edx = regs[3]; +} +#endif /* i386 && GNUC */ + + +#if defined (__x86_64__) && defined (__GNUC__) +# define HAS_X86_CPUID 1 + +static int +is_cpuid_available(void) +{ + return 1; +} + +static void +get_cpuid(unsigned int in, unsigned int *eax, unsigned int *ebx, + unsigned int *ecx, unsigned int *edx) +{ + unsigned int regs[4]; + + asm volatile + ("cpuid\n\t" + : "=a" (regs[0]), "=b" (regs[1]), "=c" (regs[2]), "=d" (regs[3]) + : "0" (in) + : "cc" + ); + + if (eax) + *eax = regs[0]; + if (ebx) + *ebx = regs[1]; + if (ecx) + *ecx = regs[2]; + if (edx) + *edx = regs[3]; +} +#endif /* x86-64 && GNUC */ + + +#ifdef HAS_X86_CPUID +static unsigned int +detect_x86_gnuc (void) +{ + char vendor_id[12+1]; + unsigned int features; + unsigned int result = 0; + + if (!is_cpuid_available()) + return 0; + + get_cpuid(0, NULL, + (unsigned int *)&vendor_id[0], + (unsigned int *)&vendor_id[8], + (unsigned int *)&vendor_id[4]); + vendor_id[12] = 0; + + if (0) + ; /* Just to make "else if" and ifdef macros look pretty. */ +#ifdef ENABLE_PADLOCK_SUPPORT + else if (!strcmp (vendor_id, "CentaurHauls")) + { + /* This is a VIA CPU. Check what PadLock features we have. */ + + /* Check for extended centaur (EAX). */ + get_cpuid(0xC0000000, &features, NULL, NULL, NULL); + + /* Has extended centaur features? */ + if (features > 0xC0000000) + { + /* Ask for the extended feature flags (EDX). */ + get_cpuid(0xC0000001, NULL, NULL, NULL, &features); + + /* Test bits 2 and 3 to see whether the RNG exists and is enabled. */ + if ((features & 0x0C) == 0x0C) + result |= HWF_PADLOCK_RNG; + + /* Test bits 6 and 7 to see whether the ACE exists and is enabled. */ + if ((features & 0xC0) == 0xC0) + result |= HWF_PADLOCK_AES; + + /* Test bits 10 and 11 to see whether the PHE exists and is + enabled. */ + if ((features & 0xC00) == 0xC00) + result |= HWF_PADLOCK_SHA; + + /* Test bits 12 and 13 to see whether the MONTMUL exists and is + enabled. */ + if ((features & 0x3000) == 0x3000) + result |= HWF_PADLOCK_MMUL; + } + } +#endif /*ENABLE_PADLOCK_SUPPORT*/ + else if (!strcmp (vendor_id, "GenuineIntel")) + { + /* This is an Intel CPU. */ + } + else if (!strcmp (vendor_id, "AuthenticAMD")) + { + /* This is an AMD CPU. */ + } + + /* Detect Intel features, that might also be supported by other + vendors. */ + + /* Get CPU info and Intel feature flags (ECX). */ + get_cpuid(1, NULL, NULL, &features, NULL); + +#ifdef ENABLE_AESNI_SUPPORT + /* Test bit 25 for AES-NI. */ + if (features & 0x02000000) + result |= HWF_INTEL_AESNI; +#endif /*ENABLE_AESNI_SUPPORT*/ +#ifdef ENABLE_DRNG_SUPPORT + /* Test bit 30 for RDRAND. */ + if (features & 0x40000000) + result |= HWF_INTEL_RDRAND; +#endif /*ENABLE_DRNG_SUPPORT*/ + + return result; +} +#endif /* HAS_X86_CPUID */ + + +unsigned int +_gcry_hwf_detect_x86 (void) +{ +#if defined (HAS_X86_CPUID) + return detect_x86_gnuc (); +#else + return 0; +#endif +} -- cgit v1.2.1