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			489 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			489 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
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|  *
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|  * Licensed under the Apache License 2.0 (the "License").  You may not use
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|  * this file except in compliance with the License.  You can obtain a copy
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|  * in the file LICENSE in the source distribution or at
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|  * https://www.openssl.org/source/license.html
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|  */
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| 
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| /*
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|  * This module is meant to be used as template for non-x87 floating-
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|  * point assembly modules. The template itself is x86_64-specific
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|  * though, as it was debugged on x86_64. So that implementor would
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|  * have to recognize platform-specific parts, UxTOy and inline asm,
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|  * and act accordingly.
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|  *
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|  * Huh? x86_64-specific code as template for non-x87? Note seven, which
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|  * is not a typo, but reference to 80-bit precision. This module on the
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|  * other hand relies on 64-bit precision operations, which are default
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|  * for x86_64 code. And since we are at it, just for sense of it,
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|  * large-block performance in cycles per processed byte for *this* code
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|  * is:
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|  *                      gcc-4.8         icc-15.0        clang-3.4(*)
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|  *
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|  * Westmere             4.96            5.09            4.37
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|  * Sandy Bridge         4.95            4.90            4.17
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|  * Haswell              4.92            4.87            3.78
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|  * Bulldozer            4.67            4.49            4.68
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|  * VIA Nano             7.07            7.05            5.98
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|  * Silvermont           10.6            9.61            12.6
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|  *
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|  * (*)  clang managed to discover parallelism and deployed SIMD;
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|  *
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|  * And for range of other platforms with unspecified gcc versions:
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|  *
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|  * Freescale e300       12.5
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|  * PPC74x0              10.8
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|  * POWER6               4.92
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|  * POWER7               4.50
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|  * POWER8               4.10
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|  *
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|  * z10                  11.2
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|  * z196+                7.30
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|  *
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|  * UltraSPARC III       16.0
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|  * SPARC T4             16.1
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|  */
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| 
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| #if !(defined(__GNUC__) && __GNUC__>=2)
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| # error "this is gcc-specific template"
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| #endif
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| 
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| #include <stdlib.h>
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| 
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| typedef unsigned char u8;
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| typedef unsigned int u32;
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| typedef unsigned long long u64;
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| typedef union { double d; u64 u; } elem64;
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| 
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| #define TWO(p)          ((double)(1ULL<<(p)))
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| #define TWO0            TWO(0)
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| #define TWO32           TWO(32)
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| #define TWO64           (TWO32*TWO(32))
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| #define TWO96           (TWO64*TWO(32))
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| #define TWO130          (TWO96*TWO(34))
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| 
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| #define EXP(p)          ((1023ULL+(p))<<52)
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| 
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| #if defined(__x86_64__) || (defined(__PPC__) && defined(__LITTLE_ENDIAN__))
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| # define U8TOU32(p)     (*(const u32 *)(p))
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| # define U32TO8(p,v)    (*(u32 *)(p) = (v))
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| #elif defined(__PPC__)
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| # define U8TOU32(p)     ({u32 ret; asm ("lwbrx	%0,0,%1":"=r"(ret):"b"(p)); ret; })
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| # define U32TO8(p,v)    asm ("stwbrx %0,0,%1"::"r"(v),"b"(p):"memory")
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| #elif defined(__s390x__)
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| # define U8TOU32(p)     ({u32 ret; asm ("lrv	%0,%1":"=d"(ret):"m"(*(u32 *)(p))); ret; })
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| # define U32TO8(p,v)    asm ("strv	%1,%0":"=m"(*(u32 *)(p)):"d"(v))
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| #endif
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| 
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| #ifndef U8TOU32
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| # define U8TOU32(p)     ((u32)(p)[0]     | (u32)(p)[1]<<8 |     \
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|                          (u32)(p)[2]<<16 | (u32)(p)[3]<<24  )
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| #endif
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| #ifndef U32TO8
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| # define U32TO8(p,v)    ((p)[0] = (u8)(v),       (p)[1] = (u8)((v)>>8), \
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|                          (p)[2] = (u8)((v)>>16), (p)[3] = (u8)((v)>>24) )
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| #endif
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| 
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| typedef struct {
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|     elem64 h[4];
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|     double r[8];
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|     double s[6];
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| } poly1305_internal;
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| 
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| /* "round toward zero (truncate), mask all exceptions" */
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| #if defined(__x86_64__)
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| static const u32 mxcsr = 0x7f80;
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| #elif defined(__PPC__)
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| static const u64 one = 1;
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| #elif defined(__s390x__)
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| static const u32 fpc = 1;
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| #elif defined(__sparc__)
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| static const u64 fsr = 1ULL<<30;
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| #elif defined(__mips__)
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| static const u32 fcsr = 1;
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| #else
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| #error "unrecognized platform"
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| #endif
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| 
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| int poly1305_init(void *ctx, const unsigned char key[16])
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| {
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|     poly1305_internal *st = (poly1305_internal *) ctx;
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|     elem64 r0, r1, r2, r3;
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| 
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|     /* h = 0, biased */
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| #if 0
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|     st->h[0].d = TWO(52)*TWO0;
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|     st->h[1].d = TWO(52)*TWO32;
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|     st->h[2].d = TWO(52)*TWO64;
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|     st->h[3].d = TWO(52)*TWO96;
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| #else
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|     st->h[0].u = EXP(52+0);
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|     st->h[1].u = EXP(52+32);
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|     st->h[2].u = EXP(52+64);
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|     st->h[3].u = EXP(52+96);
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| #endif
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| 
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|     if (key) {
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|         /*
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|          * set "truncate" rounding mode
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|          */
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| #if defined(__x86_64__)
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|         u32 mxcsr_orig;
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| 
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|         asm volatile ("stmxcsr	%0":"=m"(mxcsr_orig));
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|         asm volatile ("ldmxcsr	%0"::"m"(mxcsr));
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| #elif defined(__PPC__)
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|         double fpscr_orig, fpscr = *(double *)&one;
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| 
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|         asm volatile ("mffs	%0":"=f"(fpscr_orig));
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|         asm volatile ("mtfsf	255,%0"::"f"(fpscr));
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| #elif defined(__s390x__)
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|         u32 fpc_orig;
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| 
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|         asm volatile ("stfpc	%0":"=m"(fpc_orig));
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|         asm volatile ("lfpc	%0"::"m"(fpc));
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| #elif defined(__sparc__)
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|         u64 fsr_orig;
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| 
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|         asm volatile ("stx	%%fsr,%0":"=m"(fsr_orig));
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|         asm volatile ("ldx	%0,%%fsr"::"m"(fsr));
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| #elif defined(__mips__)
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|         u32 fcsr_orig;
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| 
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|         asm volatile ("cfc1	%0,$31":"=r"(fcsr_orig));
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|         asm volatile ("ctc1	%0,$31"::"r"(fcsr));
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| #endif
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| 
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|         /* r &= 0xffffffc0ffffffc0ffffffc0fffffff */
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|         r0.u = EXP(52+0)  | (U8TOU32(&key[0])  & 0x0fffffff);
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|         r1.u = EXP(52+32) | (U8TOU32(&key[4])  & 0x0ffffffc);
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|         r2.u = EXP(52+64) | (U8TOU32(&key[8])  & 0x0ffffffc);
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|         r3.u = EXP(52+96) | (U8TOU32(&key[12]) & 0x0ffffffc);
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| 
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|         st->r[0] = r0.d - TWO(52)*TWO0;
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|         st->r[2] = r1.d - TWO(52)*TWO32;
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|         st->r[4] = r2.d - TWO(52)*TWO64;
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|         st->r[6] = r3.d - TWO(52)*TWO96;
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| 
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|         st->s[0] = st->r[2] * (5.0/TWO130);
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|         st->s[2] = st->r[4] * (5.0/TWO130);
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|         st->s[4] = st->r[6] * (5.0/TWO130);
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| 
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|         /*
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|          * base 2^32 -> base 2^16
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|          */
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|         st->r[1] = (st->r[0] + TWO(52)*TWO(16)*TWO0) -
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|                                TWO(52)*TWO(16)*TWO0;
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|         st->r[0] -= st->r[1];
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| 
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|         st->r[3] = (st->r[2] + TWO(52)*TWO(16)*TWO32) -
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|                                TWO(52)*TWO(16)*TWO32;
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|         st->r[2] -= st->r[3];
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| 
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|         st->r[5] = (st->r[4] + TWO(52)*TWO(16)*TWO64) -
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|                                TWO(52)*TWO(16)*TWO64;
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|         st->r[4] -= st->r[5];
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| 
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|         st->r[7] = (st->r[6] + TWO(52)*TWO(16)*TWO96) -
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|                                TWO(52)*TWO(16)*TWO96;
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|         st->r[6] -= st->r[7];
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| 
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|         st->s[1] = (st->s[0] + TWO(52)*TWO(16)*TWO0/TWO96) -
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|                                TWO(52)*TWO(16)*TWO0/TWO96;
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|         st->s[0] -= st->s[1];
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| 
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|         st->s[3] = (st->s[2] + TWO(52)*TWO(16)*TWO32/TWO96) -
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|                                TWO(52)*TWO(16)*TWO32/TWO96;
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|         st->s[2] -= st->s[3];
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| 
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|         st->s[5] = (st->s[4] + TWO(52)*TWO(16)*TWO64/TWO96) -
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|                                TWO(52)*TWO(16)*TWO64/TWO96;
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|         st->s[4] -= st->s[5];
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| 
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|         /*
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|          * restore original FPU control register
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|          */
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| #if defined(__x86_64__)
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|         asm volatile ("ldmxcsr	%0"::"m"(mxcsr_orig));
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| #elif defined(__PPC__)
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|         asm volatile ("mtfsf	255,%0"::"f"(fpscr_orig));
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| #elif defined(__s390x__)
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|         asm volatile ("lfpc	%0"::"m"(fpc_orig));
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| #elif defined(__sparc__)
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|         asm volatile ("ldx	%0,%%fsr"::"m"(fsr_orig));
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| #elif defined(__mips__)
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|         asm volatile ("ctc1	%0,$31"::"r"(fcsr_orig));
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| #endif
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|     }
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| 
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|     return 0;
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| }
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| 
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| void poly1305_blocks(void *ctx, const unsigned char *inp, size_t len,
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|                      int padbit)
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| {
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|     poly1305_internal *st = (poly1305_internal *)ctx;
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|     elem64 in0, in1, in2, in3;
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|     u64 pad = (u64)padbit<<32;
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| 
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|     double x0, x1, x2, x3;
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|     double h0lo, h0hi, h1lo, h1hi, h2lo, h2hi, h3lo, h3hi;
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|     double c0lo, c0hi, c1lo, c1hi, c2lo, c2hi, c3lo, c3hi;
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| 
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|     const double r0lo = st->r[0];
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|     const double r0hi = st->r[1];
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|     const double r1lo = st->r[2];
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|     const double r1hi = st->r[3];
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|     const double r2lo = st->r[4];
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|     const double r2hi = st->r[5];
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|     const double r3lo = st->r[6];
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|     const double r3hi = st->r[7];
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| 
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|     const double s1lo = st->s[0];
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|     const double s1hi = st->s[1];
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|     const double s2lo = st->s[2];
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|     const double s2hi = st->s[3];
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|     const double s3lo = st->s[4];
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|     const double s3hi = st->s[5];
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| 
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|     /*
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|      * set "truncate" rounding mode
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|      */
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| #if defined(__x86_64__)
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|     u32 mxcsr_orig;
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| 
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|     asm volatile ("stmxcsr	%0":"=m"(mxcsr_orig));
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|     asm volatile ("ldmxcsr	%0"::"m"(mxcsr));
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| #elif defined(__PPC__)
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|     double fpscr_orig, fpscr = *(double *)&one;
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| 
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|     asm volatile ("mffs		%0":"=f"(fpscr_orig));
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|     asm volatile ("mtfsf	255,%0"::"f"(fpscr));
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| #elif defined(__s390x__)
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|     u32 fpc_orig;
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| 
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|     asm volatile ("stfpc	%0":"=m"(fpc_orig));
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|     asm volatile ("lfpc		%0"::"m"(fpc));
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| #elif defined(__sparc__)
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|     u64 fsr_orig;
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| 
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|     asm volatile ("stx		%%fsr,%0":"=m"(fsr_orig));
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|     asm volatile ("ldx		%0,%%fsr"::"m"(fsr));
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| #elif defined(__mips__)
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|     u32 fcsr_orig;
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| 
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|     asm volatile ("cfc1		%0,$31":"=r"(fcsr_orig));
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|     asm volatile ("ctc1		%0,$31"::"r"(fcsr));
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| #endif
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| 
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|     /*
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|      * load base 2^32 and de-bias
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|      */
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|     h0lo = st->h[0].d - TWO(52)*TWO0;
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|     h1lo = st->h[1].d - TWO(52)*TWO32;
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|     h2lo = st->h[2].d - TWO(52)*TWO64;
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|     h3lo = st->h[3].d - TWO(52)*TWO96;
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| 
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| #ifdef __clang__
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|     h0hi = 0;
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|     h1hi = 0;
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|     h2hi = 0;
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|     h3hi = 0;
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| #else
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|     in0.u = EXP(52+0)  | U8TOU32(&inp[0]);
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|     in1.u = EXP(52+32) | U8TOU32(&inp[4]);
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|     in2.u = EXP(52+64) | U8TOU32(&inp[8]);
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|     in3.u = EXP(52+96) | U8TOU32(&inp[12]) | pad;
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| 
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|     x0 = in0.d - TWO(52)*TWO0;
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|     x1 = in1.d - TWO(52)*TWO32;
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|     x2 = in2.d - TWO(52)*TWO64;
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|     x3 = in3.d - TWO(52)*TWO96;
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| 
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|     x0 += h0lo;
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|     x1 += h1lo;
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|     x2 += h2lo;
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|     x3 += h3lo;
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| 
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|     goto fast_entry;
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| #endif
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| 
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|     do {
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|         in0.u = EXP(52+0)  | U8TOU32(&inp[0]);
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|         in1.u = EXP(52+32) | U8TOU32(&inp[4]);
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|         in2.u = EXP(52+64) | U8TOU32(&inp[8]);
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|         in3.u = EXP(52+96) | U8TOU32(&inp[12]) | pad;
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| 
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|         x0 = in0.d - TWO(52)*TWO0;
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|         x1 = in1.d - TWO(52)*TWO32;
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|         x2 = in2.d - TWO(52)*TWO64;
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|         x3 = in3.d - TWO(52)*TWO96;
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| 
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|         /*
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|          * note that there are multiple ways to accumulate input, e.g.
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|          * one can as well accumulate to h0lo-h1lo-h1hi-h2hi...
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|          */
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|         h0lo += x0;
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|         h0hi += x1;
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|         h2lo += x2;
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|         h2hi += x3;
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| 
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|         /*
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|          * carries that cross 32n-bit (and 130-bit) boundaries
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|          */
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|         c0lo = (h0lo + TWO(52)*TWO32)  - TWO(52)*TWO32;
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|         c1lo = (h1lo + TWO(52)*TWO64)  - TWO(52)*TWO64;
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|         c2lo = (h2lo + TWO(52)*TWO96)  - TWO(52)*TWO96;
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|         c3lo = (h3lo + TWO(52)*TWO130) - TWO(52)*TWO130;
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| 
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|         c0hi = (h0hi + TWO(52)*TWO32)  - TWO(52)*TWO32;
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|         c1hi = (h1hi + TWO(52)*TWO64)  - TWO(52)*TWO64;
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|         c2hi = (h2hi + TWO(52)*TWO96)  - TWO(52)*TWO96;
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|         c3hi = (h3hi + TWO(52)*TWO130) - TWO(52)*TWO130;
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| 
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|         /*
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|          * base 2^48 -> base 2^32 with last reduction step
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|          */
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|         x1 =  (h1lo - c1lo) + c0lo;
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|         x2 =  (h2lo - c2lo) + c1lo;
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|         x3 =  (h3lo - c3lo) + c2lo;
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|         x0 =  (h0lo - c0lo) + c3lo * (5.0/TWO130);
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| 
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|         x1 += (h1hi - c1hi) + c0hi;
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|         x2 += (h2hi - c2hi) + c1hi;
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|         x3 += (h3hi - c3hi) + c2hi;
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|         x0 += (h0hi - c0hi) + c3hi * (5.0/TWO130);
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| 
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| #ifndef __clang__
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|     fast_entry:
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| #endif
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|         /*
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|          * base 2^32 * base 2^16 = base 2^48
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|          */
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|         h0lo = s3lo * x1 + s2lo * x2 + s1lo * x3 + r0lo * x0;
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|         h1lo = r0lo * x1 + s3lo * x2 + s2lo * x3 + r1lo * x0;
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|         h2lo = r1lo * x1 + r0lo * x2 + s3lo * x3 + r2lo * x0;
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|         h3lo = r2lo * x1 + r1lo * x2 + r0lo * x3 + r3lo * x0;
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| 
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|         h0hi = s3hi * x1 + s2hi * x2 + s1hi * x3 + r0hi * x0;
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|         h1hi = r0hi * x1 + s3hi * x2 + s2hi * x3 + r1hi * x0;
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|         h2hi = r1hi * x1 + r0hi * x2 + s3hi * x3 + r2hi * x0;
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|         h3hi = r2hi * x1 + r1hi * x2 + r0hi * x3 + r3hi * x0;
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| 
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|         inp += 16;
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|         len -= 16;
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| 
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|     } while (len >= 16);
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| 
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|     /*
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|      * carries that cross 32n-bit (and 130-bit) boundaries
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|      */
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|     c0lo = (h0lo + TWO(52)*TWO32)  - TWO(52)*TWO32;
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|     c1lo = (h1lo + TWO(52)*TWO64)  - TWO(52)*TWO64;
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|     c2lo = (h2lo + TWO(52)*TWO96)  - TWO(52)*TWO96;
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|     c3lo = (h3lo + TWO(52)*TWO130) - TWO(52)*TWO130;
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| 
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|     c0hi = (h0hi + TWO(52)*TWO32)  - TWO(52)*TWO32;
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|     c1hi = (h1hi + TWO(52)*TWO64)  - TWO(52)*TWO64;
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|     c2hi = (h2hi + TWO(52)*TWO96)  - TWO(52)*TWO96;
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|     c3hi = (h3hi + TWO(52)*TWO130) - TWO(52)*TWO130;
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| 
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|     /*
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|      * base 2^48 -> base 2^32 with last reduction step
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|      */
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|     x1 =  (h1lo - c1lo) + c0lo;
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|     x2 =  (h2lo - c2lo) + c1lo;
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|     x3 =  (h3lo - c3lo) + c2lo;
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|     x0 =  (h0lo - c0lo) + c3lo * (5.0/TWO130);
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| 
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|     x1 += (h1hi - c1hi) + c0hi;
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|     x2 += (h2hi - c2hi) + c1hi;
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|     x3 += (h3hi - c3hi) + c2hi;
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|     x0 += (h0hi - c0hi) + c3hi * (5.0/TWO130);
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| 
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|     /*
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|      * store base 2^32, with bias
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|      */
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|     st->h[1].d = x1 + TWO(52)*TWO32;
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|     st->h[2].d = x2 + TWO(52)*TWO64;
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|     st->h[3].d = x3 + TWO(52)*TWO96;
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|     st->h[0].d = x0 + TWO(52)*TWO0;
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| 
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|     /*
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|      * restore original FPU control register
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|      */
 | |
| #if defined(__x86_64__)
 | |
|     asm volatile ("ldmxcsr	%0"::"m"(mxcsr_orig));
 | |
| #elif defined(__PPC__)
 | |
|     asm volatile ("mtfsf	255,%0"::"f"(fpscr_orig));
 | |
| #elif defined(__s390x__)
 | |
|     asm volatile ("lfpc		%0"::"m"(fpc_orig));
 | |
| #elif defined(__sparc__)
 | |
|     asm volatile ("ldx		%0,%%fsr"::"m"(fsr_orig));
 | |
| #elif defined(__mips__)
 | |
|     asm volatile ("ctc1		%0,$31"::"r"(fcsr_orig));
 | |
| #endif
 | |
| }
 | |
| 
 | |
| void poly1305_emit(void *ctx, unsigned char mac[16], const u32 nonce[4])
 | |
| {
 | |
|     poly1305_internal *st = (poly1305_internal *) ctx;
 | |
|     u64 h0, h1, h2, h3, h4;
 | |
|     u32 g0, g1, g2, g3, g4;
 | |
|     u64 t;
 | |
|     u32 mask;
 | |
| 
 | |
|     /*
 | |
|      * thanks to bias masking exponent gives integer result
 | |
|      */
 | |
|     h0 = st->h[0].u & 0x000fffffffffffffULL;
 | |
|     h1 = st->h[1].u & 0x000fffffffffffffULL;
 | |
|     h2 = st->h[2].u & 0x000fffffffffffffULL;
 | |
|     h3 = st->h[3].u & 0x000fffffffffffffULL;
 | |
| 
 | |
|     /*
 | |
|      * can be partially reduced, so reduce...
 | |
|      */
 | |
|     h4 = h3>>32; h3 &= 0xffffffffU;
 | |
|     g4 = h4&-4;
 | |
|     h4 &= 3;
 | |
|     g4 += g4>>2;
 | |
| 
 | |
|     h0 += g4;
 | |
|     h1 += h0>>32; h0 &= 0xffffffffU;
 | |
|     h2 += h1>>32; h1 &= 0xffffffffU;
 | |
|     h3 += h2>>32; h2 &= 0xffffffffU;
 | |
| 
 | |
|     /* compute h + -p */
 | |
|     g0 = (u32)(t = h0 + 5);
 | |
|     g1 = (u32)(t = h1 + (t >> 32));
 | |
|     g2 = (u32)(t = h2 + (t >> 32));
 | |
|     g3 = (u32)(t = h3 + (t >> 32));
 | |
|     g4 = h4 + (u32)(t >> 32);
 | |
| 
 | |
|     /* if there was carry, select g0-g3 */
 | |
|     mask = 0 - (g4 >> 2);
 | |
|     g0 &= mask;
 | |
|     g1 &= mask;
 | |
|     g2 &= mask;
 | |
|     g3 &= mask;
 | |
|     mask = ~mask;
 | |
|     g0 |= (h0 & mask);
 | |
|     g1 |= (h1 & mask);
 | |
|     g2 |= (h2 & mask);
 | |
|     g3 |= (h3 & mask);
 | |
| 
 | |
|     /* mac = (h + nonce) % (2^128) */
 | |
|     g0 = (u32)(t = (u64)g0 + nonce[0]);
 | |
|     g1 = (u32)(t = (u64)g1 + (t >> 32) + nonce[1]);
 | |
|     g2 = (u32)(t = (u64)g2 + (t >> 32) + nonce[2]);
 | |
|     g3 = (u32)(t = (u64)g3 + (t >> 32) + nonce[3]);
 | |
| 
 | |
|     U32TO8(mac + 0, g0);
 | |
|     U32TO8(mac + 4, g1);
 | |
|     U32TO8(mac + 8, g2);
 | |
|     U32TO8(mac + 12, g3);
 | |
| }
 |