From de6d2c524430287c699aaa898c1325da6afea539 Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Wed, 20 Jun 2018 22:39:07 +0100 Subject: Update dependencies --- vendor/golang.org/x/crypto/poly1305/sum_ref.go | 139 +++++++++++++++++++++++++ 1 file changed, 139 insertions(+) create mode 100644 vendor/golang.org/x/crypto/poly1305/sum_ref.go (limited to 'vendor/golang.org/x/crypto/poly1305/sum_ref.go') diff --git a/vendor/golang.org/x/crypto/poly1305/sum_ref.go b/vendor/golang.org/x/crypto/poly1305/sum_ref.go new file mode 100644 index 0000000..c4d59bd --- /dev/null +++ b/vendor/golang.org/x/crypto/poly1305/sum_ref.go @@ -0,0 +1,139 @@ +// Copyright 2012 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package poly1305 + +import "encoding/binary" + +// sumGeneric generates an authenticator for msg using a one-time key and +// puts the 16-byte result into out. This is the generic implementation of +// Sum and should be called if no assembly implementation is available. +func sumGeneric(out *[TagSize]byte, msg []byte, key *[32]byte) { + var ( + h0, h1, h2, h3, h4 uint32 // the hash accumulators + r0, r1, r2, r3, r4 uint64 // the r part of the key + ) + + r0 = uint64(binary.LittleEndian.Uint32(key[0:]) & 0x3ffffff) + r1 = uint64((binary.LittleEndian.Uint32(key[3:]) >> 2) & 0x3ffff03) + r2 = uint64((binary.LittleEndian.Uint32(key[6:]) >> 4) & 0x3ffc0ff) + r3 = uint64((binary.LittleEndian.Uint32(key[9:]) >> 6) & 0x3f03fff) + r4 = uint64((binary.LittleEndian.Uint32(key[12:]) >> 8) & 0x00fffff) + + R1, R2, R3, R4 := r1*5, r2*5, r3*5, r4*5 + + for len(msg) >= TagSize { + // h += msg + h0 += binary.LittleEndian.Uint32(msg[0:]) & 0x3ffffff + h1 += (binary.LittleEndian.Uint32(msg[3:]) >> 2) & 0x3ffffff + h2 += (binary.LittleEndian.Uint32(msg[6:]) >> 4) & 0x3ffffff + h3 += (binary.LittleEndian.Uint32(msg[9:]) >> 6) & 0x3ffffff + h4 += (binary.LittleEndian.Uint32(msg[12:]) >> 8) | (1 << 24) + + // h *= r + d0 := (uint64(h0) * r0) + (uint64(h1) * R4) + (uint64(h2) * R3) + (uint64(h3) * R2) + (uint64(h4) * R1) + d1 := (d0 >> 26) + (uint64(h0) * r1) + (uint64(h1) * r0) + (uint64(h2) * R4) + (uint64(h3) * R3) + (uint64(h4) * R2) + d2 := (d1 >> 26) + (uint64(h0) * r2) + (uint64(h1) * r1) + (uint64(h2) * r0) + (uint64(h3) * R4) + (uint64(h4) * R3) + d3 := (d2 >> 26) + (uint64(h0) * r3) + (uint64(h1) * r2) + (uint64(h2) * r1) + (uint64(h3) * r0) + (uint64(h4) * R4) + d4 := (d3 >> 26) + (uint64(h0) * r4) + (uint64(h1) * r3) + (uint64(h2) * r2) + (uint64(h3) * r1) + (uint64(h4) * r0) + + // h %= p + h0 = uint32(d0) & 0x3ffffff + h1 = uint32(d1) & 0x3ffffff + h2 = uint32(d2) & 0x3ffffff + h3 = uint32(d3) & 0x3ffffff + h4 = uint32(d4) & 0x3ffffff + + h0 += uint32(d4>>26) * 5 + h1 += h0 >> 26 + h0 = h0 & 0x3ffffff + + msg = msg[TagSize:] + } + + if len(msg) > 0 { + var block [TagSize]byte + off := copy(block[:], msg) + block[off] = 0x01 + + // h += msg + h0 += binary.LittleEndian.Uint32(block[0:]) & 0x3ffffff + h1 += (binary.LittleEndian.Uint32(block[3:]) >> 2) & 0x3ffffff + h2 += (binary.LittleEndian.Uint32(block[6:]) >> 4) & 0x3ffffff + h3 += (binary.LittleEndian.Uint32(block[9:]) >> 6) & 0x3ffffff + h4 += (binary.LittleEndian.Uint32(block[12:]) >> 8) + + // h *= r + d0 := (uint64(h0) * r0) + (uint64(h1) * R4) + (uint64(h2) * R3) + (uint64(h3) * R2) + (uint64(h4) * R1) + d1 := (d0 >> 26) + (uint64(h0) * r1) + (uint64(h1) * r0) + (uint64(h2) * R4) + (uint64(h3) * R3) + (uint64(h4) * R2) + d2 := (d1 >> 26) + (uint64(h0) * r2) + (uint64(h1) * r1) + (uint64(h2) * r0) + (uint64(h3) * R4) + (uint64(h4) * R3) + d3 := (d2 >> 26) + (uint64(h0) * r3) + (uint64(h1) * r2) + (uint64(h2) * r1) + (uint64(h3) * r0) + (uint64(h4) * R4) + d4 := (d3 >> 26) + (uint64(h0) * r4) + (uint64(h1) * r3) + (uint64(h2) * r2) + (uint64(h3) * r1) + (uint64(h4) * r0) + + // h %= p + h0 = uint32(d0) & 0x3ffffff + h1 = uint32(d1) & 0x3ffffff + h2 = uint32(d2) & 0x3ffffff + h3 = uint32(d3) & 0x3ffffff + h4 = uint32(d4) & 0x3ffffff + + h0 += uint32(d4>>26) * 5 + h1 += h0 >> 26 + h0 = h0 & 0x3ffffff + } + + // h %= p reduction + h2 += h1 >> 26 + h1 &= 0x3ffffff + h3 += h2 >> 26 + h2 &= 0x3ffffff + h4 += h3 >> 26 + h3 &= 0x3ffffff + h0 += 5 * (h4 >> 26) + h4 &= 0x3ffffff + h1 += h0 >> 26 + h0 &= 0x3ffffff + + // h - p + t0 := h0 + 5 + t1 := h1 + (t0 >> 26) + t2 := h2 + (t1 >> 26) + t3 := h3 + (t2 >> 26) + t4 := h4 + (t3 >> 26) - (1 << 26) + t0 &= 0x3ffffff + t1 &= 0x3ffffff + t2 &= 0x3ffffff + t3 &= 0x3ffffff + + // select h if h < p else h - p + t_mask := (t4 >> 31) - 1 + h_mask := ^t_mask + h0 = (h0 & h_mask) | (t0 & t_mask) + h1 = (h1 & h_mask) | (t1 & t_mask) + h2 = (h2 & h_mask) | (t2 & t_mask) + h3 = (h3 & h_mask) | (t3 & t_mask) + h4 = (h4 & h_mask) | (t4 & t_mask) + + // h %= 2^128 + h0 |= h1 << 26 + h1 = ((h1 >> 6) | (h2 << 20)) + h2 = ((h2 >> 12) | (h3 << 14)) + h3 = ((h3 >> 18) | (h4 << 8)) + + // s: the s part of the key + // tag = (h + s) % (2^128) + t := uint64(h0) + uint64(binary.LittleEndian.Uint32(key[16:])) + h0 = uint32(t) + t = uint64(h1) + uint64(binary.LittleEndian.Uint32(key[20:])) + (t >> 32) + h1 = uint32(t) + t = uint64(h2) + uint64(binary.LittleEndian.Uint32(key[24:])) + (t >> 32) + h2 = uint32(t) + t = uint64(h3) + uint64(binary.LittleEndian.Uint32(key[28:])) + (t >> 32) + h3 = uint32(t) + + binary.LittleEndian.PutUint32(out[0:], h0) + binary.LittleEndian.PutUint32(out[4:], h1) + binary.LittleEndian.PutUint32(out[8:], h2) + binary.LittleEndian.PutUint32(out[12:], h3) +} -- cgit v1.2.3