From bd9957e6e28506c4431ce8d3cadbc0a04905b15e Mon Sep 17 00:00:00 2001 From: Adam Langley Date: Tue, 23 Jun 2015 16:28:07 -0700 Subject: Handle RDRAND failures. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit I mistakenly believed that only RDSEED could fail. However, the Intel manuals state that RDRAND can fail too. This change cherry-picks the following BoringSSL changes: 2cac3506 – Handle RDRAND failures. 248abbd7 – Add missing comma in .type pragma for rdrand code. Change-Id: Icdc56a50ce36e9c525063583882c676a5312d313 --- win-x86_64/crypto/rand/rdrand-x86_64.asm | 50 +++++++++++++++++++++++++++++++- 1 file changed, 49 insertions(+), 1 deletion(-) (limited to 'win-x86_64/crypto') diff --git a/win-x86_64/crypto/rand/rdrand-x86_64.asm b/win-x86_64/crypto/rand/rdrand-x86_64.asm index a63ea69..4c03791 100644 --- a/win-x86_64/crypto/rand/rdrand-x86_64.asm +++ b/win-x86_64/crypto/rand/rdrand-x86_64.asm @@ -5,6 +5,9 @@ default rel section .text code align=64 + + + global CRYPTO_rdrand ALIGN 16 @@ -16,7 +19,52 @@ $L$SEH_begin_CRYPTO_rdrand: mov rdi,rcx -DB 0x48,0x0f,0xc7,0xf0 + xor rax,rax + + +DB 0x48,0x0f,0xc7,0xf1 + + adc rax,rax + mov QWORD[rdi],rcx + mov rdi,QWORD[8+rsp] ;WIN64 epilogue + mov rsi,QWORD[16+rsp] + DB 0F3h,0C3h ;repret + + + + + +global CRYPTO_rdrand_multiple8_buf + +ALIGN 16 +CRYPTO_rdrand_multiple8_buf: + mov QWORD[8+rsp],rdi ;WIN64 prologue + mov QWORD[16+rsp],rsi + mov rax,rsp +$L$SEH_begin_CRYPTO_rdrand_multiple8_buf: + mov rdi,rcx + mov rsi,rdx + + + test rsi,rsi + jz NEAR $L$out + mov rdx,8 +$L$loop: + + +DB 0x48,0x0f,0xc7,0xf1 + jnc NEAR $L$err + mov QWORD[rdi],rcx + add rdi,rdx + sub rsi,rdx + jnz NEAR $L$loop +$L$out: + mov rax,1 + mov rdi,QWORD[8+rsp] ;WIN64 epilogue + mov rsi,QWORD[16+rsp] + DB 0F3h,0C3h ;repret +$L$err: + xor rax,rax mov rdi,QWORD[8+rsp] ;WIN64 epilogue mov rsi,QWORD[16+rsp] DB 0F3h,0C3h ;repret -- cgit v1.1