1 #!/usr/bin/env perl 2 3 # Copyright (c) 2015, Google Inc. 4 # 5 # Permission to use, copy, modify, and/or distribute this software for any 6 # purpose with or without fee is hereby granted, provided that the above 7 # copyright notice and this permission notice appear in all copies. 8 # 9 # THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 12 # SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION 14 # OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN 15 # CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ 16 17 $flavour = shift; 18 $output = shift; 19 if ($flavour =~ /\./) { $output = $flavour; undef $flavour; } 20 21 $0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1; 22 ( $xlate="${dir}../../../perlasm/x86_64-xlate.pl" and -f $xlate) or 23 die "can't locate x86_64-xlate.pl"; 24 25 open OUT,"| \"$^X\" $xlate $flavour $output"; 26 *STDOUT=*OUT; 27 28 print<<___; 29 .text 30 31 # CRYPTO_rdrand writes eight bytes of random data from the hardware RNG to 32 # |out|. It returns one on success or zero on hardware failure. 33 # int CRYPTO_rdrand(uint8_t out[8]); 34 .globl CRYPTO_rdrand 35 .type CRYPTO_rdrand,\@function,1 36 .align 16 37 CRYPTO_rdrand: 38 xorq %rax, %rax 39 # This is rdrand %rcx. It sets rcx to a random value and sets the carry 40 # flag on success. 41 .byte 0x48, 0x0f, 0xc7, 0xf1 42 # An add-with-carry of zero effectively sets %rax to the carry flag. 43 adcq %rax, %rax 44 movq %rcx, 0(%rdi) 45 retq 46 47 # CRYPTO_rdrand_multiple8_buf fills |len| bytes at |buf| with random data from 48 # the hardware RNG. The |len| argument must be a multiple of eight. It returns 49 # one on success and zero on hardware failure. 50 # int CRYPTO_rdrand_multiple8_buf(uint8_t *buf, size_t len); 51 .globl CRYPTO_rdrand_multiple8_buf 52 .type CRYPTO_rdrand_multiple8_buf,\@function,2 53 .align 16 54 CRYPTO_rdrand_multiple8_buf: 55 test %rsi, %rsi 56 jz .Lout 57 movq \$8, %rdx 58 .Lloop: 59 # This is rdrand %rcx. It sets rcx to a random value and sets the carry 60 # flag on success. 61 .byte 0x48, 0x0f, 0xc7, 0xf1 62 jnc .Lerr 63 movq %rcx, 0(%rdi) 64 addq %rdx, %rdi 65 subq %rdx, %rsi 66 jnz .Lloop 67 .Lout: 68 movq \$1, %rax 69 retq 70 .Lerr: 71 xorq %rax, %rax 72 retq 73 ___ 74 75 close STDOUT; # flush 76
