diff options
Diffstat (limited to 'libgo/go/golang_org/x/crypto/poly1305/sum_s390x.go')
-rw-r--r-- | libgo/go/golang_org/x/crypto/poly1305/sum_s390x.go | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/libgo/go/golang_org/x/crypto/poly1305/sum_s390x.go b/libgo/go/golang_org/x/crypto/poly1305/sum_s390x.go new file mode 100644 index 0000000..7a266ce --- /dev/null +++ b/libgo/go/golang_org/x/crypto/poly1305/sum_s390x.go @@ -0,0 +1,49 @@ +// Copyright 2018 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. + +// +build s390x,go1.11,!gccgo,!appengine + +package poly1305 + +// hasVectorFacility reports whether the machine supports +// the vector facility (vx). +func hasVectorFacility() bool + +// hasVMSLFacility reports whether the machine supports +// Vector Multiply Sum Logical (VMSL). +func hasVMSLFacility() bool + +var hasVX = hasVectorFacility() +var hasVMSL = hasVMSLFacility() + +// poly1305vx is an assembly implementation of Poly1305 that uses vector +// instructions. It must only be called if the vector facility (vx) is +// available. +//go:noescape +func poly1305vx(out *[16]byte, m *byte, mlen uint64, key *[32]byte) + +// poly1305vmsl is an assembly implementation of Poly1305 that uses vector +// instructions, including VMSL. It must only be called if the vector facility (vx) is +// available and if VMSL is supported. +//go:noescape +func poly1305vmsl(out *[16]byte, m *byte, mlen uint64, key *[32]byte) + +// Sum generates an authenticator for m using a one-time key and puts the +// 16-byte result into out. Authenticating two different messages with the same +// key allows an attacker to forge messages at will. +func Sum(out *[16]byte, m []byte, key *[32]byte) { + if hasVX { + var mPtr *byte + if len(m) > 0 { + mPtr = &m[0] + } + if hasVMSL && len(m) > 256 { + poly1305vmsl(out, mPtr, uint64(len(m)), key) + } else { + poly1305vx(out, mPtr, uint64(len(m)), key) + } + } else { + sumGeneric(out, m, key) + } +} |