Merge pull request #22037 from hashicorp/jbardin/ssh-alive

monitor ssh connection live-ness

communicator/ssh/communicator.go

@@ -27,17 +27,23 @@ import (
 const (
 	// DefaultShebang is added at the top of a SSH script file
 	DefaultShebang = "#!/bin/sh\n"
+)
+
+var (
+	// randShared is a global random generator object that is shared.  This must be
+	// shared since it is seeded by the current time and creating multiple can
+	// result in the same values. By using a shared RNG we assure different numbers
+	// per call.
+	randLock   sync.Mutex
+	randShared *rand.Rand
 
 	// enable ssh keeplive probes by default
 	keepAliveInterval = 2 * time.Second
-)
 
-// randShared is a global random generator object that is shared.
-// This must be shared since it is seeded by the current time and
-// creating multiple can result in the same values. By using a shared
-// RNG we assure different numbers per call.
-var randLock sync.Mutex
-var randShared *rand.Rand
+	// max time to wait for for a KeepAlive response before considering the
+	// connection to be dead.
+	maxKeepAliveDelay = 120 * time.Second
+)
 
 // Communicator represents the SSH communicator
 type Communicator struct {
@@ -225,20 +231,50 @@ func (c *Communicator) Connect(o terraform.UIOutput) (err error) {
 	// long-running commands.
 	log.Printf("[DEBUG] starting ssh KeepAlives")
 	go func() {
-		t := time.NewTicker(keepAliveInterval)
-		defer t.Stop()
-		for {
-			select {
-			case <-t.C:
-				// there's no useful response to these, just abort when there's
-				// an error.
-				_, _, err := c.client.SendRequest("keepalive@terraform.io", true, nil)
-				if err != nil {
+		defer cancelKeepAlive()
+		// Along with the KeepAlives generating packets to keep the tcp
+		// connection open, we will use the replies to verify liveness of the
+		// connection. This will prevent dead connections from blocking the
+		// provisioner indefinitely.
+		respCh := make(chan error, 1)
+
+		go func() {
+			t := time.NewTicker(keepAliveInterval)
+			defer t.Stop()
+			for {
+				select {
+				case <-t.C:
+					_, _, err := c.client.SendRequest("keepalive@terraform.io", true, nil)
+					respCh <- err
+				case <-ctx.Done():
 					return
 				}
+			}
+		}()
+
+		after := time.NewTimer(maxKeepAliveDelay)
+		defer after.Stop()
+
+		for {
+			select {
+			case err := <-respCh:
+				if err != nil {
+					log.Printf("[ERROR] ssh keepalive: %s", err)
+					sshConn.Close()
+					return
+				}
+			case <-after.C:
+				// abort after too many missed keepalives
+				log.Println("[ERROR] no reply from ssh server")
+				sshConn.Close()
+				return
 			case <-ctx.Done():
 				return
 			}
+			if !after.Stop() {
+				<-after.C
+			}
+			after.Reset(maxKeepAliveDelay)
 		}
 	}()
 

communicator/ssh/communicator_test.go

@@ -100,16 +100,19 @@ func newMockLineServer(t *testing.T, signer ssh.Signer, pubKey string) string {
 
 			go func(in <-chan *ssh.Request) {
 				for req := range in {
+					// since this channel's requests are serviced serially,
+					// this will block keepalive probes, and can simulate a
+					// hung connection.
+					if bytes.Contains(req.Payload, []byte("sleep")) {
+						time.Sleep(time.Second)
+					}
+
 					if req.WantReply {
 						req.Reply(true, nil)
 					}
 				}
 			}(requests)
 
-			go func(newChannel ssh.NewChannel) {
-				conn.OpenChannel(newChannel.ChannelType(), nil)
-			}(newChannel)
-
 			defer channel.Close()
 		}
 		conn.Close()
@@ -182,6 +185,10 @@ func TestStart(t *testing.T) {
 // TestKeepAlives verifies that the keepalive messages don't interfere with
 // normal operation of the client.
 func TestKeepAlives(t *testing.T) {
+	ivl := keepAliveInterval
+	keepAliveInterval = 250 * time.Millisecond
+	defer func() { keepAliveInterval = ivl }()
+
 	address := newMockLineServer(t, nil, testClientPublicKey)
 	parts := strings.Split(address, ":")
 
@@ -193,7 +200,6 @@ func TestKeepAlives(t *testing.T) {
 				"password": "pass",
 				"host":     parts[0],
 				"port":     parts[1],
-				"timeout":  "30s",
 			},
 		},
 	}
@@ -209,11 +215,11 @@ func TestKeepAlives(t *testing.T) {
 
 	var cmd remote.Cmd
 	stdout := new(bytes.Buffer)
-	cmd.Command = "echo foo"
+	cmd.Command = "sleep"
 	cmd.Stdout = stdout
 
 	// wait a bit before executing the command, so that at least 1 keepalive is sent
-	time.Sleep(3 * time.Second)
+	time.Sleep(500 * time.Millisecond)
 
 	err = c.Start(&cmd)
 	if err != nil {
@@ -221,6 +227,52 @@ func TestKeepAlives(t *testing.T) {
 	}
 }
 
+// TestDeadConnection verifies that failed keepalive messages will eventually
+// kill the connection.
+func TestFailedKeepAlives(t *testing.T) {
+	ivl := keepAliveInterval
+	del := maxKeepAliveDelay
+	maxKeepAliveDelay = 500 * time.Millisecond
+	keepAliveInterval = 250 * time.Millisecond
+	defer func() {
+		keepAliveInterval = ivl
+		maxKeepAliveDelay = del
+	}()
+
+	address := newMockLineServer(t, nil, testClientPublicKey)
+	parts := strings.Split(address, ":")
+
+	r := &terraform.InstanceState{
+		Ephemeral: terraform.EphemeralState{
+			ConnInfo: map[string]string{
+				"type":     "ssh",
+				"user":     "user",
+				"password": "pass",
+				"host":     parts[0],
+				"port":     parts[1],
+			},
+		},
+	}
+
+	c, err := New(r)
+	if err != nil {
+		t.Fatalf("error creating communicator: %s", err)
+	}
+
+	if err := c.Connect(nil); err != nil {
+		t.Fatal(err)
+	}
+	var cmd remote.Cmd
+	stdout := new(bytes.Buffer)
+	cmd.Command = "sleep"
+	cmd.Stdout = stdout
+
+	err = c.Start(&cmd)
+	if err == nil {
+		t.Fatal("expected connection error")
+	}
+}
+
 func TestLostConnection(t *testing.T) {
 	address := newMockLineServer(t, nil, testClientPublicKey)
 	parts := strings.Split(address, ":")

go.mod

@@ -120,7 +120,7 @@ require (
 	go.uber.org/atomic v1.3.2 // indirect
 	go.uber.org/multierr v1.1.0 // indirect
 	go.uber.org/zap v1.9.1 // indirect
-	golang.org/x/crypto v0.0.0-20190426145343-a29dc8fdc734
+	golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4
 	golang.org/x/net v0.0.0-20190502183928-7f726cade0ab
 	golang.org/x/oauth2 v0.0.0-20190220154721-9b3c75971fc9
 	google.golang.org/api v0.1.0

go.sum

@@ -451,6 +451,8 @@ golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2 h1:VklqNMn3ovrHsnt90Pveol
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20190426145343-a29dc8fdc734 h1:p/H982KKEjUnLJkM3tt/LemDnOc1GiZL5FCVlORJ5zo=
 golang.org/x/crypto v0.0.0-20190426145343-a29dc8fdc734/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4 h1:HuIa8hRrWRSrqYzx1qI49NNxhdi2PrY7gxVSq1JjLDc=
+golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/lint v0.0.0-20180702182130-06c8688daad7/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
 golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=

vendor/golang.org/x/crypto/ed25519/ed25519.go

@@ -2,6 +2,11 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// In Go 1.13, the ed25519 package was promoted to the standard library as
+// crypto/ed25519, and this package became a wrapper for the standard library one.
+//
+// +build !go1.13
+
 // Package ed25519 implements the Ed25519 signature algorithm. See
 // https://ed25519.cr.yp.to/.
 //

vendor/golang.org/x/crypto/ed25519/ed25519_go113.go

@@ -0,0 +1,73 @@
+// Copyright 2019 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 go1.13
+
+// Package ed25519 implements the Ed25519 signature algorithm. See
+// https://ed25519.cr.yp.to/.
+//
+// These functions are also compatible with the “Ed25519” function defined in
+// RFC 8032. However, unlike RFC 8032's formulation, this package's private key
+// representation includes a public key suffix to make multiple signing
+// operations with the same key more efficient. This package refers to the RFC
+// 8032 private key as the “seed”.
+//
+// Beginning with Go 1.13, the functionality of this package was moved to the
+// standard library as crypto/ed25519. This package only acts as a compatibility
+// wrapper.
+package ed25519
+
+import (
+	"crypto/ed25519"
+	"io"
+)
+
+const (
+	// PublicKeySize is the size, in bytes, of public keys as used in this package.
+	PublicKeySize = 32
+	// PrivateKeySize is the size, in bytes, of private keys as used in this package.
+	PrivateKeySize = 64
+	// SignatureSize is the size, in bytes, of signatures generated and verified by this package.
+	SignatureSize = 64
+	// SeedSize is the size, in bytes, of private key seeds. These are the private key representations used by RFC 8032.
+	SeedSize = 32
+)
+
+// PublicKey is the type of Ed25519 public keys.
+//
+// This type is an alias for crypto/ed25519's PublicKey type.
+// See the crypto/ed25519 package for the methods on this type.
+type PublicKey = ed25519.PublicKey
+
+// PrivateKey is the type of Ed25519 private keys. It implements crypto.Signer.
+//
+// This type is an alias for crypto/ed25519's PrivateKey type.
+// See the crypto/ed25519 package for the methods on this type.
+type PrivateKey = ed25519.PrivateKey
+
+// GenerateKey generates a public/private key pair using entropy from rand.
+// If rand is nil, crypto/rand.Reader will be used.
+func GenerateKey(rand io.Reader) (PublicKey, PrivateKey, error) {
+	return ed25519.GenerateKey(rand)
+}
+
+// NewKeyFromSeed calculates a private key from a seed. It will panic if
+// len(seed) is not SeedSize. This function is provided for interoperability
+// with RFC 8032. RFC 8032's private keys correspond to seeds in this
+// package.
+func NewKeyFromSeed(seed []byte) PrivateKey {
+	return ed25519.NewKeyFromSeed(seed)
+}
+
+// Sign signs the message with privateKey and returns a signature. It will
+// panic if len(privateKey) is not PrivateKeySize.
+func Sign(privateKey PrivateKey, message []byte) []byte {
+	return ed25519.Sign(privateKey, message)
+}
+
+// Verify reports whether sig is a valid signature of message by publicKey. It
+// will panic if len(publicKey) is not PublicKeySize.
+func Verify(publicKey PublicKey, message, sig []byte) bool {
+	return ed25519.Verify(publicKey, message, sig)
+}

vendor/golang.org/x/crypto/internal/chacha20/asm_ppc64le.s

@@ -0,0 +1,668 @@
+// Copyright 2019 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.
+
+// Based on CRYPTOGAMS code with the following comment:
+// # ====================================================================
+// # Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
+// # project. The module is, however, dual licensed under OpenSSL and
+// # CRYPTOGAMS licenses depending on where you obtain it. For further
+// # details see http://www.openssl.org/~appro/cryptogams/.
+// # ====================================================================
+
+// Original code can be found at the link below:
+// https://github.com/dot-asm/cryptogams/commit/a60f5b50ed908e91e5c39ca79126a4a876d5d8ff
+
+// There are some differences between CRYPTOGAMS code and this one. The round
+// loop for "_int" isn't the same as the original. Some adjustments were
+// necessary because there are less vector registers available.  For example, some
+// X variables (r12, r13, r14, and r15) share the same register used by the
+// counter. The original code uses ctr to name the counter. Here we use CNT
+// because golang uses CTR as the counter register name.
+
+// +build ppc64le,!gccgo,!appengine
+
+#include "textflag.h"
+
+#define OUT  R3
+#define INP  R4
+#define LEN  R5
+#define KEY  R6
+#define CNT  R7
+
+#define TEMP R8
+
+#define X0   R11
+#define X1   R12
+#define X2   R14
+#define X3   R15
+#define X4   R16
+#define X5   R17
+#define X6   R18
+#define X7   R19
+#define X8   R20
+#define X9   R21
+#define X10  R22
+#define X11  R23
+#define X12  R24
+#define X13  R25
+#define X14  R26
+#define X15  R27
+
+#define CON0 X0
+#define CON1 X1
+#define CON2 X2
+#define CON3 X3
+
+#define KEY0 X4
+#define KEY1 X5
+#define KEY2 X6
+#define KEY3 X7
+#define KEY4 X8
+#define KEY5 X9
+#define KEY6 X10
+#define KEY7 X11
+
+#define CNT0 X12
+#define CNT1 X13
+#define CNT2 X14
+#define CNT3 X15
+
+#define TMP0 R9
+#define TMP1 R10
+#define TMP2 R28
+#define TMP3 R29
+
+#define CONSTS  R8
+
+#define A0      V0
+#define B0      V1
+#define C0      V2
+#define D0      V3
+#define A1      V4
+#define B1      V5
+#define C1      V6
+#define D1      V7
+#define A2      V8
+#define B2      V9
+#define C2      V10
+#define D2      V11
+#define T0      V12
+#define T1      V13
+#define T2      V14
+
+#define K0      V15
+#define K1      V16
+#define K2      V17
+#define K3      V18
+#define K4      V19
+#define K5      V20
+
+#define FOUR    V21
+#define SIXTEEN V22
+#define TWENTY4 V23
+#define TWENTY  V24
+#define TWELVE  V25
+#define TWENTY5 V26
+#define SEVEN   V27
+
+#define INPPERM V28
+#define OUTPERM V29
+#define OUTMASK V30
+
+#define DD0     V31
+#define DD1     SEVEN
+#define DD2     T0
+#define DD3     T1
+#define DD4     T2
+
+DATA  ·consts+0x00(SB)/8, $0x3320646e61707865
+DATA  ·consts+0x08(SB)/8, $0x6b20657479622d32
+DATA  ·consts+0x10(SB)/8, $0x0000000000000001
+DATA  ·consts+0x18(SB)/8, $0x0000000000000000
+DATA  ·consts+0x20(SB)/8, $0x0000000000000004
+DATA  ·consts+0x28(SB)/8, $0x0000000000000000
+DATA  ·consts+0x30(SB)/8, $0x0a0b08090e0f0c0d
+DATA  ·consts+0x38(SB)/8, $0x0203000106070405
+DATA  ·consts+0x40(SB)/8, $0x090a0b080d0e0f0c
+DATA  ·consts+0x48(SB)/8, $0x0102030005060704
+GLOBL ·consts(SB), RODATA, $80
+
+//func chaCha20_ctr32_vmx(out, inp *byte, len int, key *[32]byte, counter *[16]byte)
+TEXT ·chaCha20_ctr32_vmx(SB),NOSPLIT|NOFRAME,$0
+	// Load the arguments inside the registers
+	MOVD out+0(FP), OUT
+	MOVD inp+8(FP), INP
+	MOVD len+16(FP), LEN
+	MOVD key+24(FP), KEY
+	MOVD counter+32(FP), CNT
+
+	MOVD $·consts(SB), CONSTS // point to consts addr
+
+	MOVD $16, X0
+	MOVD $32, X1
+	MOVD $48, X2
+	MOVD $64, X3
+	MOVD $31, X4
+	MOVD $15, X5
+
+	// Load key
+	LVX  (KEY)(R0), K1
+	LVSR (KEY)(R0), T0
+	LVX  (KEY)(X0), K2
+	LVX  (KEY)(X4), DD0
+
+	// Load counter
+	LVX  (CNT)(R0), K3
+	LVSR (CNT)(R0), T1
+	LVX  (CNT)(X5), DD1
+
+	// Load constants
+	LVX (CONSTS)(R0), K0
+	LVX (CONSTS)(X0), K5
+	LVX (CONSTS)(X1), FOUR
+	LVX (CONSTS)(X2), SIXTEEN
+	LVX (CONSTS)(X3), TWENTY4
+
+	// Align key and counter
+	VPERM K2,  K1, T0, K1
+	VPERM DD0, K2, T0, K2
+	VPERM DD1, K3, T1, K3
+
+	// Load counter to GPR
+	MOVWZ 0(CNT), CNT0
+	MOVWZ 4(CNT), CNT1
+	MOVWZ 8(CNT), CNT2
+	MOVWZ 12(CNT), CNT3
+
+	// Adjust vectors for the initial state
+	VADDUWM K3, K5, K3
+	VADDUWM K3, K5, K4
+	VADDUWM K4, K5, K5
+
+	// Synthesized constants
+	VSPLTISW $-12, TWENTY
+	VSPLTISW $12, TWELVE
+	VSPLTISW $-7, TWENTY5
+
+	VXOR T0, T0, T0
+	VSPLTISW $-1, OUTMASK
+	LVSR (INP)(R0), INPPERM
+	LVSL (OUT)(R0), OUTPERM
+	VPERM OUTMASK, T0, OUTPERM, OUTMASK
+
+loop_outer_vmx:
+	// Load constant
+	MOVD $0x61707865, CON0
+	MOVD $0x3320646e, CON1
+	MOVD $0x79622d32, CON2
+	MOVD $0x6b206574, CON3
+
+	VOR K0, K0, A0
+	VOR K0, K0, A1
+	VOR K0, K0, A2
+	VOR K1, K1, B0
+
+	MOVD $10, TEMP
+
+	// Load key to GPR
+	MOVWZ 0(KEY), X4
+	MOVWZ 4(KEY), X5
+	MOVWZ 8(KEY), X6
+	MOVWZ 12(KEY), X7
+	VOR K1, K1, B1
+	VOR K1, K1, B2
+	MOVWZ 16(KEY), X8
+	MOVWZ  0(CNT), X12
+	MOVWZ 20(KEY), X9
+	MOVWZ 4(CNT), X13
+	VOR K2, K2, C0
+	VOR K2, K2, C1
+	MOVWZ 24(KEY), X10
+	MOVWZ 8(CNT), X14
+	VOR K2, K2, C2
+	VOR K3, K3, D0
+	MOVWZ 28(KEY), X11
+	MOVWZ 12(CNT), X15
+	VOR K4, K4, D1
+	VOR K5, K5, D2
+
+	MOVD X4, TMP0
+	MOVD X5, TMP1
+	MOVD X6, TMP2
+	MOVD X7, TMP3
+	VSPLTISW $7, SEVEN
+
+	MOVD TEMP, CTR
+
+loop_vmx:
+	// CRYPTOGAMS uses a macro to create a loop using perl. This isn't possible
+	// using assembly macros.  Therefore, the macro expansion result was used
+	// in order to maintain the algorithm efficiency.
+	// This loop generates three keystream blocks using VMX instructions and,
+	// in parallel, one keystream block using scalar instructions.
+	ADD X4, X0, X0
+	ADD X5, X1, X1
+	VADDUWM A0, B0, A0
+	VADDUWM A1, B1, A1
+	ADD X6, X2, X2
+	ADD X7, X3, X3
+	VADDUWM A2, B2, A2
+	VXOR D0, A0, D0
+	XOR X0, X12, X12
+	XOR X1, X13, X13
+	VXOR D1, A1, D1
+	VXOR D2, A2, D2
+	XOR X2, X14, X14
+	XOR X3, X15, X15
+	VPERM D0, D0, SIXTEEN, D0
+	VPERM D1, D1, SIXTEEN, D1
+	ROTLW $16, X12, X12
+	ROTLW $16, X13, X13
+	VPERM D2, D2, SIXTEEN, D2
+	VADDUWM C0, D0, C0
+	ROTLW $16, X14, X14
+	ROTLW $16, X15, X15
+	VADDUWM C1, D1, C1
+	VADDUWM C2, D2, C2
+	ADD X12, X8, X8
+	ADD X13, X9, X9
+	VXOR B0, C0, T0
+	VXOR B1, C1, T1
+	ADD X14, X10, X10
+	ADD X15, X11, X11
+	VXOR B2, C2, T2
+	VRLW T0, TWELVE, B0
+	XOR X8, X4, X4
+	XOR X9, X5, X5
+	VRLW T1, TWELVE, B1
+	VRLW T2, TWELVE, B2
+	XOR X10, X6, X6
+	XOR X11, X7, X7
+	VADDUWM A0, B0, A0
+	VADDUWM A1, B1, A1
+	ROTLW $12, X4, X4
+	ROTLW $12, X5, X5
+	VADDUWM A2, B2, A2
+	VXOR D0, A0, D0
+	ROTLW $12, X6, X6
+	ROTLW $12, X7, X7
+	VXOR D1, A1, D1
+	VXOR D2, A2, D2
+	ADD X4, X0, X0
+	ADD X5, X1, X1
+	VPERM D0, D0, TWENTY4, D0
+	VPERM D1, D1, TWENTY4, D1
+	ADD X6, X2, X2
+	ADD X7, X3, X3
+	VPERM D2, D2, TWENTY4, D2
+	VADDUWM C0, D0, C0
+	XOR X0, X12, X12
+	XOR X1, X13, X13
+	VADDUWM C1, D1, C1
+	VADDUWM C2, D2, C2
+	XOR X2, X14, X14
+	XOR X3, X15, X15
+	VXOR B0, C0, T0
+	VXOR B1, C1, T1
+	ROTLW $8, X12, X12
+	ROTLW $8, X13, X13
+	VXOR B2, C2, T2
+	VRLW T0, SEVEN, B0
+	ROTLW $8, X14, X14
+	ROTLW $8, X15, X15
+	VRLW T1, SEVEN, B1
+	VRLW T2, SEVEN, B2
+	ADD X12, X8, X8
+	ADD X13, X9, X9
+	VSLDOI $8, C0, C0, C0
+	VSLDOI $8, C1, C1, C1
+	ADD X14, X10, X10
+	ADD X15, X11, X11
+	VSLDOI $8, C2, C2, C2
+	VSLDOI $12, B0, B0, B0
+	XOR X8, X4, X4
+	XOR X9, X5, X5
+	VSLDOI $12, B1, B1, B1
+	VSLDOI $12, B2, B2, B2
+	XOR X10, X6, X6
+	XOR X11, X7, X7
+	VSLDOI $4, D0, D0, D0
+	VSLDOI $4, D1, D1, D1
+	ROTLW $7, X4, X4
+	ROTLW $7, X5, X5
+	VSLDOI $4, D2, D2, D2
+	VADDUWM A0, B0, A0
+	ROTLW $7, X6, X6
+	ROTLW $7, X7, X7
+	VADDUWM A1, B1, A1
+	VADDUWM A2, B2, A2
+	ADD X5, X0, X0
+	ADD X6, X1, X1
+	VXOR D0, A0, D0
+	VXOR D1, A1, D1
+	ADD X7, X2, X2
+	ADD X4, X3, X3
+	VXOR D2, A2, D2
+	VPERM D0, D0, SIXTEEN, D0
+	XOR X0, X15, X15
+	XOR X1, X12, X12
+	VPERM D1, D1, SIXTEEN, D1
+	VPERM D2, D2, SIXTEEN, D2
+	XOR X2, X13, X13
+	XOR X3, X14, X14
+	VADDUWM C0, D0, C0
+	VADDUWM C1, D1, C1
+	ROTLW $16, X15, X15
+	ROTLW $16, X12, X12
+	VADDUWM C2, D2, C2
+	VXOR B0, C0, T0
+	ROTLW $16, X13, X13
+	ROTLW $16, X14, X14
+	VXOR B1, C1, T1
+	VXOR B2, C2, T2
+	ADD X15, X10, X10
+	ADD X12, X11, X11
+	VRLW T0, TWELVE, B0
+	VRLW T1, TWELVE, B1
+	ADD X13, X8, X8
+	ADD X14, X9, X9
+	VRLW T2, TWELVE, B2
+	VADDUWM A0, B0, A0
+	XOR X10, X5, X5
+	XOR X11, X6, X6
+	VADDUWM A1, B1, A1
+	VADDUWM A2, B2, A2
+	XOR X8, X7, X7
+	XOR X9, X4, X4
+	VXOR D0, A0, D0
+	VXOR D1, A1, D1
+	ROTLW $12, X5, X5
+	ROTLW $12, X6, X6
+	VXOR D2, A2, D2
+	VPERM D0, D0, TWENTY4, D0
+	ROTLW $12, X7, X7
+	ROTLW $12, X4, X4
+	VPERM D1, D1, TWENTY4, D1
+	VPERM D2, D2, TWENTY4, D2
+	ADD X5, X0, X0
+	ADD X6, X1, X1
+	VADDUWM C0, D0, C0
+	VADDUWM C1, D1, C1
+	ADD X7, X2, X2
+	ADD X4, X3, X3
+	VADDUWM C2, D2, C2
+	VXOR B0, C0, T0
+	XOR X0, X15, X15
+	XOR X1, X12, X12
+	VXOR B1, C1, T1
+	VXOR B2, C2, T2
+	XOR X2, X13, X13
+	XOR X3, X14, X14
+	VRLW T0, SEVEN, B0
+	VRLW T1, SEVEN, B1
+	ROTLW $8, X15, X15
+	ROTLW $8, X12, X12
+	VRLW T2, SEVEN, B2
+	VSLDOI $8, C0, C0, C0
+	ROTLW $8, X13, X13
+	ROTLW $8, X14, X14
+	VSLDOI $8, C1, C1, C1
+	VSLDOI $8, C2, C2, C2
+	ADD X15, X10, X10
+	ADD X12, X11, X11
+	VSLDOI $4, B0, B0, B0
+	VSLDOI $4, B1, B1, B1
+	ADD X13, X8, X8
+	ADD X14, X9, X9
+	VSLDOI $4, B2, B2, B2
+	VSLDOI $12, D0, D0, D0
+	XOR X10, X5, X5
+	XOR X11, X6, X6
+	VSLDOI $12, D1, D1, D1
+	VSLDOI $12, D2, D2, D2
+	XOR X8, X7, X7
+	XOR X9, X4, X4
+	ROTLW $7, X5, X5
+	ROTLW $7, X6, X6
+	ROTLW $7, X7, X7
+	ROTLW $7, X4, X4
+	BC 0x10, 0, loop_vmx
+
+	SUB $256, LEN, LEN
+
+	// Accumulate key block
+	ADD $0x61707865, X0, X0
+	ADD $0x3320646e, X1, X1
+	ADD $0x79622d32, X2, X2
+	ADD $0x6b206574, X3, X3
+	ADD TMP0, X4, X4
+	ADD TMP1, X5, X5
+	ADD TMP2, X6, X6
+	ADD TMP3, X7, X7
+	MOVWZ 16(KEY), TMP0
+	MOVWZ 20(KEY), TMP1
+	MOVWZ 24(KEY), TMP2
+	MOVWZ 28(KEY), TMP3
+	ADD TMP0, X8, X8
+	ADD TMP1, X9, X9
+	ADD TMP2, X10, X10
+	ADD TMP3, X11, X11
+
+	MOVWZ 12(CNT), TMP0
+	MOVWZ 8(CNT), TMP1
+	MOVWZ 4(CNT), TMP2
+	MOVWZ 0(CNT), TEMP
+	ADD TMP0, X15, X15
+	ADD TMP1, X14, X14
+	ADD TMP2, X13, X13
+	ADD TEMP, X12, X12
+
+	// Accumulate key block
+	VADDUWM A0, K0, A0
+	VADDUWM A1, K0, A1
+	VADDUWM A2, K0, A2
+	VADDUWM B0, K1, B0
+	VADDUWM B1, K1, B1
+	VADDUWM B2, K1, B2
+	VADDUWM C0, K2, C0
+	VADDUWM C1, K2, C1
+	VADDUWM C2, K2, C2
+	VADDUWM D0, K3, D0
+	VADDUWM D1, K4, D1
+	VADDUWM D2, K5, D2
+
+	// Increment counter
+	ADD $4, TEMP, TEMP
+	MOVW TEMP, 0(CNT)
+
+	VADDUWM K3, FOUR, K3
+	VADDUWM K4, FOUR, K4
+	VADDUWM K5, FOUR, K5
+
+	// XOR the input slice (INP) with the keystream, which is stored in GPRs (X0-X3).
+
+	// Load input (aligned or not)
+	MOVWZ 0(INP), TMP0
+	MOVWZ 4(INP), TMP1
+	MOVWZ 8(INP), TMP2
+	MOVWZ 12(INP), TMP3
+
+	// XOR with input
+	XOR TMP0, X0, X0
+	XOR TMP1, X1, X1
+	XOR TMP2, X2, X2
+	XOR TMP3, X3, X3
+	MOVWZ 16(INP), TMP0
+	MOVWZ 20(INP), TMP1
+	MOVWZ 24(INP), TMP2
+	MOVWZ 28(INP), TMP3
+	XOR TMP0, X4, X4
+	XOR TMP1, X5, X5
+	XOR TMP2, X6, X6
+	XOR TMP3, X7, X7
+	MOVWZ 32(INP), TMP0
+	MOVWZ 36(INP), TMP1
+	MOVWZ 40(INP), TMP2
+	MOVWZ 44(INP), TMP3
+	XOR TMP0, X8, X8
+	XOR TMP1, X9, X9
+	XOR TMP2, X10, X10
+	XOR TMP3, X11, X11
+	MOVWZ 48(INP), TMP0
+	MOVWZ 52(INP), TMP1
+	MOVWZ 56(INP), TMP2
+	MOVWZ 60(INP), TMP3
+	XOR TMP0, X12, X12
+	XOR TMP1, X13, X13
+	XOR TMP2, X14, X14
+	XOR TMP3, X15, X15
+
+	// Store output (aligned or not)
+	MOVW X0, 0(OUT)
+	MOVW X1, 4(OUT)
+	MOVW X2, 8(OUT)
+	MOVW X3, 12(OUT)
+
+	ADD $64, INP, INP // INP points to the end of the slice for the alignment code below
+
+	MOVW X4, 16(OUT)
+	MOVD $16, TMP0
+	MOVW X5, 20(OUT)
+	MOVD $32, TMP1
+	MOVW X6, 24(OUT)
+	MOVD $48, TMP2
+	MOVW X7, 28(OUT)
+	MOVD $64, TMP3
+	MOVW X8, 32(OUT)
+	MOVW X9, 36(OUT)
+	MOVW X10, 40(OUT)
+	MOVW X11, 44(OUT)
+	MOVW X12, 48(OUT)
+	MOVW X13, 52(OUT)
+	MOVW X14, 56(OUT)
+	MOVW X15, 60(OUT)
+	ADD $64, OUT, OUT
+
+	// Load input
+	LVX (INP)(R0), DD0
+	LVX (INP)(TMP0), DD1
+	LVX (INP)(TMP1), DD2
+	LVX (INP)(TMP2), DD3
+	LVX (INP)(TMP3), DD4
+	ADD $64, INP, INP
+
+	VPERM DD1, DD0, INPPERM, DD0 // Align input
+	VPERM DD2, DD1, INPPERM, DD1
+	VPERM DD3, DD2, INPPERM, DD2
+	VPERM DD4, DD3, INPPERM, DD3
+	VXOR A0, DD0, A0 // XOR with input
+	VXOR B0, DD1, B0
+	LVX (INP)(TMP0), DD1 // Keep loading input
+	VXOR C0, DD2, C0
+	LVX (INP)(TMP1), DD2
+	VXOR D0, DD3, D0
+	LVX (INP)(TMP2), DD3
+	LVX (INP)(TMP3), DD0
+	ADD $64, INP, INP
+	MOVD $63, TMP3 // 63 is not a typo
+	VPERM A0, A0, OUTPERM, A0
+	VPERM B0, B0, OUTPERM, B0
+	VPERM C0, C0, OUTPERM, C0
+	VPERM D0, D0, OUTPERM, D0
+
+	VPERM DD1, DD4, INPPERM, DD4 // Align input
+	VPERM DD2, DD1, INPPERM, DD1
+	VPERM DD3, DD2, INPPERM, DD2
+	VPERM DD0, DD3, INPPERM, DD3
+	VXOR A1, DD4, A1
+	VXOR B1, DD1, B1
+	LVX (INP)(TMP0), DD1 // Keep loading
+	VXOR C1, DD2, C1
+	LVX (INP)(TMP1), DD2
+	VXOR D1, DD3, D1
+	LVX (INP)(TMP2), DD3
+
+	// Note that the LVX address is always rounded down to the nearest 16-byte
+	// boundary, and that it always points to at most 15 bytes beyond the end of
+	// the slice, so we cannot cross a page boundary.
+	LVX (INP)(TMP3), DD4 // Redundant in aligned case.
+	ADD $64, INP, INP
+	VPERM A1, A1, OUTPERM, A1 // Pre-misalign output
+	VPERM B1, B1, OUTPERM, B1
+	VPERM C1, C1, OUTPERM, C1
+	VPERM D1, D1, OUTPERM, D1
+
+	VPERM DD1, DD0, INPPERM, DD0 // Align Input
+	VPERM DD2, DD1, INPPERM, DD1
+	VPERM DD3, DD2, INPPERM, DD2
+	VPERM DD4, DD3, INPPERM, DD3
+	VXOR A2, DD0, A2
+	VXOR B2, DD1, B2
+	VXOR C2, DD2, C2
+	VXOR D2, DD3, D2
+	VPERM A2, A2, OUTPERM, A2
+	VPERM B2, B2, OUTPERM, B2
+	VPERM C2, C2, OUTPERM, C2
+	VPERM D2, D2, OUTPERM, D2
+
+	ANDCC $15, OUT, X1 // Is out aligned?
+	MOVD OUT, X0
+
+	VSEL A0, B0, OUTMASK, DD0 // Collect pre-misaligned output
+	VSEL B0, C0, OUTMASK, DD1
+	VSEL C0, D0, OUTMASK, DD2
+	VSEL D0, A1, OUTMASK, DD3
+	VSEL A1, B1, OUTMASK, B0
+	VSEL B1, C1, OUTMASK, C0
+	VSEL C1, D1, OUTMASK, D0
+	VSEL D1, A2, OUTMASK, A1
+	VSEL A2, B2, OUTMASK, B1
+	VSEL B2, C2, OUTMASK, C1
+	VSEL C2, D2, OUTMASK, D1
+
+	STVX DD0, (OUT+TMP0)
+	STVX DD1, (OUT+TMP1)
+	STVX DD2, (OUT+TMP2)
+	ADD $64, OUT, OUT
+	STVX DD3, (OUT+R0)
+	STVX B0, (OUT+TMP0)
+	STVX C0, (OUT+TMP1)
+	STVX D0, (OUT+TMP2)
+	ADD $64, OUT, OUT
+	STVX A1, (OUT+R0)
+	STVX B1, (OUT+TMP0)
+	STVX C1, (OUT+TMP1)
+	STVX D1, (OUT+TMP2)
+	ADD $64, OUT, OUT
+
+	BEQ aligned_vmx
+
+	SUB X1, OUT, X2 // in misaligned case edges
+	MOVD $0, X3 // are written byte-by-byte
+
+unaligned_tail_vmx:
+	STVEBX D2, (X2+X3)
+	ADD $1, X3, X3
+	CMPW X3, X1
+	BNE unaligned_tail_vmx
+	SUB X1, X0, X2
+
+unaligned_head_vmx:
+	STVEBX A0, (X2+X1)
+	CMPW X1, $15
+	ADD $1, X1, X1
+	BNE unaligned_head_vmx
+
+	CMPU LEN, $255 // done with 256-byte block yet?
+	BGT loop_outer_vmx
+
+	JMP done_vmx
+
+aligned_vmx:
+	STVX A0, (X0+R0)
+	CMPU LEN, $255 // done with 256-byte block yet?
+	BGT loop_outer_vmx
+
+done_vmx:
+	RET

vendor/golang.org/x/crypto/internal/chacha20/chacha_noasm.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !arm64,!s390x arm64,!go1.11 gccgo appengine
+// +build !ppc64le,!arm64,!s390x arm64,!go1.11 gccgo appengine
 
 package chacha20
 

vendor/golang.org/x/crypto/internal/chacha20/chacha_ppc64le.go

@@ -0,0 +1,52 @@
+// Copyright 2019 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 ppc64le,!gccgo,!appengine
+
+package chacha20
+
+import "encoding/binary"
+
+const (
+	bufSize = 256
+	haveAsm = true
+)
+
+//go:noescape
+func chaCha20_ctr32_vmx(out, inp *byte, len int, key *[8]uint32, counter *uint32)
+
+func (c *Cipher) xorKeyStreamAsm(dst, src []byte) {
+	if len(src) >= bufSize {
+		chaCha20_ctr32_vmx(&dst[0], &src[0], len(src)-len(src)%bufSize, &c.key, &c.counter)
+	}
+	if len(src)%bufSize != 0 {
+		chaCha20_ctr32_vmx(&c.buf[0], &c.buf[0], bufSize, &c.key, &c.counter)
+		start := len(src) - len(src)%bufSize
+		ts, td, tb := src[start:], dst[start:], c.buf[:]
+		// Unroll loop to XOR 32 bytes per iteration.
+		for i := 0; i < len(ts)-32; i += 32 {
+			td, tb = td[:len(ts)], tb[:len(ts)] // bounds check elimination
+			s0 := binary.LittleEndian.Uint64(ts[0:8])
+			s1 := binary.LittleEndian.Uint64(ts[8:16])
+			s2 := binary.LittleEndian.Uint64(ts[16:24])
+			s3 := binary.LittleEndian.Uint64(ts[24:32])
+			b0 := binary.LittleEndian.Uint64(tb[0:8])
+			b1 := binary.LittleEndian.Uint64(tb[8:16])
+			b2 := binary.LittleEndian.Uint64(tb[16:24])
+			b3 := binary.LittleEndian.Uint64(tb[24:32])
+			binary.LittleEndian.PutUint64(td[0:8], s0^b0)
+			binary.LittleEndian.PutUint64(td[8:16], s1^b1)
+			binary.LittleEndian.PutUint64(td[16:24], s2^b2)
+			binary.LittleEndian.PutUint64(td[24:32], s3^b3)
+			ts, td, tb = ts[32:], td[32:], tb[32:]
+		}
+		td, tb = td[:len(ts)], tb[:len(ts)] // bounds check elimination
+		for i, v := range ts {
+			td[i] = tb[i] ^ v
+		}
+		c.len = bufSize - (len(src) % bufSize)
+
+	}
+
+}

vendor/golang.org/x/crypto/openpgp/keys.go

@@ -504,7 +504,7 @@ const defaultRSAKeyBits = 2048
 // which may be empty but must not contain any of "()<>\x00".
 // If config is nil, sensible defaults will be used.
 func NewEntity(name, comment, email string, config *packet.Config) (*Entity, error) {
-	currentTime := config.Now()
+	creationTime := config.Now()
 
 	bits := defaultRSAKeyBits
 	if config != nil && config.RSABits != 0 {
@@ -525,8 +525,8 @@ func NewEntity(name, comment, email string, config *packet.Config) (*Entity, err
 	}
 
 	e := &Entity{
-		PrimaryKey: packet.NewRSAPublicKey(currentTime, &signingPriv.PublicKey),
-		PrivateKey: packet.NewRSAPrivateKey(currentTime, signingPriv),
+		PrimaryKey: packet.NewRSAPublicKey(creationTime, &signingPriv.PublicKey),
+		PrivateKey: packet.NewRSAPrivateKey(creationTime, signingPriv),
 		Identities: make(map[string]*Identity),
 	}
 	isPrimaryId := true
@@ -534,7 +534,7 @@ func NewEntity(name, comment, email string, config *packet.Config) (*Entity, err
 		Name:   uid.Id,
 		UserId: uid,
 		SelfSignature: &packet.Signature{
-			CreationTime: currentTime,
+			CreationTime: creationTime,
 			SigType:      packet.SigTypePositiveCert,
 			PubKeyAlgo:   packet.PubKeyAlgoRSA,
 			Hash:         config.Hash(),
@@ -563,10 +563,10 @@ func NewEntity(name, comment, email string, config *packet.Config) (*Entity, err
 
 	e.Subkeys = make([]Subkey, 1)
 	e.Subkeys[0] = Subkey{
-		PublicKey:  packet.NewRSAPublicKey(currentTime, &encryptingPriv.PublicKey),
-		PrivateKey: packet.NewRSAPrivateKey(currentTime, encryptingPriv),
+		PublicKey:  packet.NewRSAPublicKey(creationTime, &encryptingPriv.PublicKey),
+		PrivateKey: packet.NewRSAPrivateKey(creationTime, encryptingPriv),
 		Sig: &packet.Signature{
-			CreationTime:              currentTime,
+			CreationTime:              creationTime,
 			SigType:                   packet.SigTypeSubkeyBinding,
 			PubKeyAlgo:                packet.PubKeyAlgoRSA,
 			Hash:                      config.Hash(),

vendor/golang.org/x/crypto/openpgp/packet/private_key.go

@@ -36,49 +36,49 @@ type PrivateKey struct {
 	iv            []byte
 }
 
-func NewRSAPrivateKey(currentTime time.Time, priv *rsa.PrivateKey) *PrivateKey {
+func NewRSAPrivateKey(creationTime time.Time, priv *rsa.PrivateKey) *PrivateKey {
 	pk := new(PrivateKey)
-	pk.PublicKey = *NewRSAPublicKey(currentTime, &priv.PublicKey)
+	pk.PublicKey = *NewRSAPublicKey(creationTime, &priv.PublicKey)
 	pk.PrivateKey = priv
 	return pk
 }
 
-func NewDSAPrivateKey(currentTime time.Time, priv *dsa.PrivateKey) *PrivateKey {
+func NewDSAPrivateKey(creationTime time.Time, priv *dsa.PrivateKey) *PrivateKey {
 	pk := new(PrivateKey)
-	pk.PublicKey = *NewDSAPublicKey(currentTime, &priv.PublicKey)
+	pk.PublicKey = *NewDSAPublicKey(creationTime, &priv.PublicKey)
 	pk.PrivateKey = priv
 	return pk
 }
 
-func NewElGamalPrivateKey(currentTime time.Time, priv *elgamal.PrivateKey) *PrivateKey {
+func NewElGamalPrivateKey(creationTime time.Time, priv *elgamal.PrivateKey) *PrivateKey {
 	pk := new(PrivateKey)
-	pk.PublicKey = *NewElGamalPublicKey(currentTime, &priv.PublicKey)
+	pk.PublicKey = *NewElGamalPublicKey(creationTime, &priv.PublicKey)
 	pk.PrivateKey = priv
 	return pk
 }
 
-func NewECDSAPrivateKey(currentTime time.Time, priv *ecdsa.PrivateKey) *PrivateKey {
+func NewECDSAPrivateKey(creationTime time.Time, priv *ecdsa.PrivateKey) *PrivateKey {
 	pk := new(PrivateKey)
-	pk.PublicKey = *NewECDSAPublicKey(currentTime, &priv.PublicKey)
+	pk.PublicKey = *NewECDSAPublicKey(creationTime, &priv.PublicKey)
 	pk.PrivateKey = priv
 	return pk
 }
 
 // NewSignerPrivateKey creates a PrivateKey from a crypto.Signer that
 // implements RSA or ECDSA.
-func NewSignerPrivateKey(currentTime time.Time, signer crypto.Signer) *PrivateKey {
+func NewSignerPrivateKey(creationTime time.Time, signer crypto.Signer) *PrivateKey {
 	pk := new(PrivateKey)
 	// In general, the public Keys should be used as pointers. We still
 	// type-switch on the values, for backwards-compatibility.
 	switch pubkey := signer.Public().(type) {
 	case *rsa.PublicKey:
-		pk.PublicKey = *NewRSAPublicKey(currentTime, pubkey)
+		pk.PublicKey = *NewRSAPublicKey(creationTime, pubkey)
 	case rsa.PublicKey:
-		pk.PublicKey = *NewRSAPublicKey(currentTime, &pubkey)
+		pk.PublicKey = *NewRSAPublicKey(creationTime, &pubkey)
 	case *ecdsa.PublicKey:
-		pk.PublicKey = *NewECDSAPublicKey(currentTime, pubkey)
+		pk.PublicKey = *NewECDSAPublicKey(creationTime, pubkey)
 	case ecdsa.PublicKey:
-		pk.PublicKey = *NewECDSAPublicKey(currentTime, &pubkey)
+		pk.PublicKey = *NewECDSAPublicKey(creationTime, &pubkey)
 	default:
 		panic("openpgp: unknown crypto.Signer type in NewSignerPrivateKey")
 	}

vendor/golang.org/x/crypto/poly1305/mac_noasm.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build !amd64 gccgo appengine
+// +build !amd64,!ppc64le gccgo appengine
 
 package poly1305
 

vendor/golang.org/x/crypto/poly1305/sum_noasm.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build s390x,!go1.11 !arm,!amd64,!s390x gccgo appengine nacl
+// +build s390x,!go1.11 !arm,!amd64,!s390x,!ppc64le gccgo appengine nacl
 
 package poly1305
 

vendor/golang.org/x/crypto/poly1305/sum_ppc64le.go

@@ -0,0 +1,68 @@
+// Copyright 2019 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 ppc64le,!gccgo,!appengine
+
+package poly1305
+
+//go:noescape
+func initialize(state *[7]uint64, key *[32]byte)
+
+//go:noescape
+func update(state *[7]uint64, msg []byte)
+
+//go:noescape
+func finalize(tag *[TagSize]byte, state *[7]uint64)
+
+// 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) {
+	h := newMAC(key)
+	h.Write(m)
+	h.Sum(out)
+}
+
+func newMAC(key *[32]byte) (h mac) {
+	initialize(&h.state, key)
+	return
+}
+
+type mac struct {
+	state [7]uint64 // := uint64{ h0, h1, h2, r0, r1, pad0, pad1 }
+
+	buffer [TagSize]byte
+	offset int
+}
+
+func (h *mac) Write(p []byte) (n int, err error) {
+	n = len(p)
+	if h.offset > 0 {
+		remaining := TagSize - h.offset
+		if n < remaining {
+			h.offset += copy(h.buffer[h.offset:], p)
+			return n, nil
+		}
+		copy(h.buffer[h.offset:], p[:remaining])
+		p = p[remaining:]
+		h.offset = 0
+		update(&h.state, h.buffer[:])
+	}
+	if nn := len(p) - (len(p) % TagSize); nn > 0 {
+		update(&h.state, p[:nn])
+		p = p[nn:]
+	}
+	if len(p) > 0 {
+		h.offset += copy(h.buffer[h.offset:], p)
+	}
+	return n, nil
+}
+
+func (h *mac) Sum(out *[16]byte) {
+	state := h.state
+	if h.offset > 0 {
+		update(&state, h.buffer[:h.offset])
+	}
+	finalize(out, &state)
+}

vendor/golang.org/x/crypto/poly1305/sum_ppc64le.s

@@ -0,0 +1,247 @@
+// Copyright 2019 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 ppc64le,!gccgo,!appengine
+
+#include "textflag.h"
+
+// This was ported from the amd64 implementation.
+
+#define POLY1305_ADD(msg, h0, h1, h2, t0, t1, t2) \
+	MOVD (msg), t0;  \
+	MOVD 8(msg), t1; \
+	MOVD $1, t2;     \
+	ADDC t0, h0, h0; \
+	ADDE t1, h1, h1; \
+	ADDE t2, h2;     \
+	ADD  $16, msg
+
+#define POLY1305_MUL(h0, h1, h2, r0, r1, t0, t1, t2, t3, t4, t5) \
+	MULLD  r0, h0, t0;  \
+	MULLD  r0, h1, t4;  \
+	MULHDU r0, h0, t1;  \
+	MULHDU r0, h1, t5;  \
+	ADDC   t4, t1, t1;  \
+	MULLD  r0, h2, t2;  \
+	ADDZE  t5;          \
+	MULHDU r1, h0, t4;  \
+	MULLD  r1, h0, h0;  \
+	ADD    t5, t2, t2;  \
+	ADDC   h0, t1, t1;  \
+	MULLD  h2, r1, t3;  \
+	ADDZE  t4, h0;      \
+	MULHDU r1, h1, t5;  \
+	MULLD  r1, h1, t4;  \
+	ADDC   t4, t2, t2;  \
+	ADDE   t5, t3, t3;  \
+	ADDC   h0, t2, t2;  \
+	MOVD   $-4, t4;     \
+	MOVD   t0, h0;      \
+	MOVD   t1, h1;      \
+	ADDZE  t3;          \
+	ANDCC  $3, t2, h2;  \
+	AND    t2, t4, t0;  \
+	ADDC   t0, h0, h0;  \
+	ADDE   t3, h1, h1;  \
+	SLD    $62, t3, t4; \
+	SRD    $2, t2;      \
+	ADDZE  h2;          \
+	OR     t4, t2, t2;  \
+	SRD    $2, t3;      \
+	ADDC   t2, h0, h0;  \
+	ADDE   t3, h1, h1;  \
+	ADDZE  h2
+
+DATA ·poly1305Mask<>+0x00(SB)/8, $0x0FFFFFFC0FFFFFFF
+DATA ·poly1305Mask<>+0x08(SB)/8, $0x0FFFFFFC0FFFFFFC
+GLOBL ·poly1305Mask<>(SB), RODATA, $16
+
+// func update(state *[7]uint64, msg []byte)
+
+TEXT ·update(SB), $0-32
+	MOVD state+0(FP), R3
+	MOVD msg_base+8(FP), R4
+	MOVD msg_len+16(FP), R5
+
+	MOVD 0(R3), R8   // h0
+	MOVD 8(R3), R9   // h1
+	MOVD 16(R3), R10 // h2
+	MOVD 24(R3), R11 // r0
+	MOVD 32(R3), R12 // r1
+
+	CMP R5, $16
+	BLT bytes_between_0_and_15
+
+loop:
+	POLY1305_ADD(R4, R8, R9, R10, R20, R21, R22)
+
+multiply:
+	POLY1305_MUL(R8, R9, R10, R11, R12, R16, R17, R18, R14, R20, R21)
+	ADD $-16, R5
+	CMP R5, $16
+	BGE loop
+
+bytes_between_0_and_15:
+	CMP  $0, R5
+	BEQ  done
+	MOVD $0, R16 // h0
+	MOVD $0, R17 // h1
+
+flush_buffer:
+	CMP R5, $8
+	BLE just1
+
+	MOVD $8, R21
+	SUB  R21, R5, R21
+
+	// Greater than 8 -- load the rightmost remaining bytes in msg
+	// and put into R17 (h1)
+	MOVD (R4)(R21), R17
+	MOVD $16, R22
+
+	// Find the offset to those bytes
+	SUB R5, R22, R22
+	SLD $3, R22
+
+	// Shift to get only the bytes in msg
+	SRD R22, R17, R17
+
+	// Put 1 at high end
+	MOVD $1, R23
+	SLD  $3, R21
+	SLD  R21, R23, R23
+	OR   R23, R17, R17
+
+	// Remainder is 8
+	MOVD $8, R5
+
+just1:
+	CMP R5, $8
+	BLT less8
+
+	// Exactly 8
+	MOVD (R4), R16
+
+	CMP $0, R17
+
+	// Check if we've already set R17; if not
+	// set 1 to indicate end of msg.
+	BNE  carry
+	MOVD $1, R17
+	BR   carry
+
+less8:
+	MOVD  $0, R16   // h0
+	MOVD  $0, R22   // shift count
+	CMP   R5, $4
+	BLT   less4
+	MOVWZ (R4), R16
+	ADD   $4, R4
+	ADD   $-4, R5
+	MOVD  $32, R22
+
+less4:
+	CMP   R5, $2
+	BLT   less2
+	MOVHZ (R4), R21
+	SLD   R22, R21, R21
+	OR    R16, R21, R16
+	ADD   $16, R22
+	ADD   $-2, R5
+	ADD   $2, R4
+
+less2:
+	CMP   $0, R5
+	BEQ   insert1
+	MOVBZ (R4), R21
+	SLD   R22, R21, R21
+	OR    R16, R21, R16
+	ADD   $8, R22
+
+insert1:
+	// Insert 1 at end of msg
+	MOVD $1, R21
+	SLD  R22, R21, R21
+	OR   R16, R21, R16
+
+carry:
+	// Add new values to h0, h1, h2
+	ADDC R16, R8
+	ADDE R17, R9
+	ADDE $0, R10
+	MOVD $16, R5
+	ADD  R5, R4
+	BR   multiply
+
+done:
+	// Save h0, h1, h2 in state
+	MOVD R8, 0(R3)
+	MOVD R9, 8(R3)
+	MOVD R10, 16(R3)
+	RET
+
+// func initialize(state *[7]uint64, key *[32]byte)
+TEXT ·initialize(SB), $0-16
+	MOVD state+0(FP), R3
+	MOVD key+8(FP), R4
+
+	// state[0...7] is initialized with zero
+	// Load key
+	MOVD 0(R4), R5
+	MOVD 8(R4), R6
+	MOVD 16(R4), R7
+	MOVD 24(R4), R8
+
+	// Address of key mask
+	MOVD $·poly1305Mask<>(SB), R9
+
+	// Save original key in state
+	MOVD R7, 40(R3)
+	MOVD R8, 48(R3)
+
+	// Get mask
+	MOVD (R9), R7
+	MOVD 8(R9), R8
+
+	// And with key
+	AND R5, R7, R5
+	AND R6, R8, R6
+
+	// Save masked key in state
+	MOVD R5, 24(R3)
+	MOVD R6, 32(R3)
+	RET
+
+// func finalize(tag *[TagSize]byte, state *[7]uint64)
+TEXT ·finalize(SB), $0-16
+	MOVD tag+0(FP), R3
+	MOVD state+8(FP), R4
+
+	// Get h0, h1, h2 from state
+	MOVD 0(R4), R5
+	MOVD 8(R4), R6
+	MOVD 16(R4), R7
+
+	// Save h0, h1
+	MOVD  R5, R8
+	MOVD  R6, R9
+	MOVD  $3, R20
+	MOVD  $-1, R21
+	SUBC  $-5, R5
+	SUBE  R21, R6
+	SUBE  R20, R7
+	MOVD  $0, R21
+	SUBZE R21
+
+	// Check for carry
+	CMP  $0, R21
+	ISEL $2, R5, R8, R5
+	ISEL $2, R6, R9, R6
+	MOVD 40(R4), R8
+	MOVD 48(R4), R9
+	ADDC R8, R5
+	ADDE R9, R6
+	MOVD R5, 0(R3)
+	MOVD R6, 8(R3)
+	RET

vendor/golang.org/x/crypto/ssh/client_auth.go

@@ -523,3 +523,117 @@ func (r *retryableAuthMethod) method() string {
 func RetryableAuthMethod(auth AuthMethod, maxTries int) AuthMethod {
 	return &retryableAuthMethod{authMethod: auth, maxTries: maxTries}
 }
+
+// GSSAPIWithMICAuthMethod is an AuthMethod with "gssapi-with-mic" authentication.
+// See RFC 4462 section 3
+// gssAPIClient is implementation of the GSSAPIClient interface, see the definition of the interface for details.
+// target is the server host you want to log in to.
+func GSSAPIWithMICAuthMethod(gssAPIClient GSSAPIClient, target string) AuthMethod {
+	if gssAPIClient == nil {
+		panic("gss-api client must be not nil with enable gssapi-with-mic")
+	}
+	return &gssAPIWithMICCallback{gssAPIClient: gssAPIClient, target: target}
+}
+
+type gssAPIWithMICCallback struct {
+	gssAPIClient GSSAPIClient
+	target       string
+}
+
+func (g *gssAPIWithMICCallback) auth(session []byte, user string, c packetConn, rand io.Reader) (authResult, []string, error) {
+	m := &userAuthRequestMsg{
+		User:    user,
+		Service: serviceSSH,
+		Method:  g.method(),
+	}
+	// The GSS-API authentication method is initiated when the client sends an SSH_MSG_USERAUTH_REQUEST.
+	// See RFC 4462 section 3.2.
+	m.Payload = appendU32(m.Payload, 1)
+	m.Payload = appendString(m.Payload, string(krb5OID))
+	if err := c.writePacket(Marshal(m)); err != nil {
+		return authFailure, nil, err
+	}
+	// The server responds to the SSH_MSG_USERAUTH_REQUEST with either an
+	// SSH_MSG_USERAUTH_FAILURE if none of the mechanisms are supported or
+	// with an SSH_MSG_USERAUTH_GSSAPI_RESPONSE.
+	// See RFC 4462 section 3.3.
+	// OpenSSH supports Kerberos V5 mechanism only for GSS-API authentication,so I don't want to check
+	// selected mech if it is valid.
+	packet, err := c.readPacket()
+	if err != nil {
+		return authFailure, nil, err
+	}
+	userAuthGSSAPIResp := &userAuthGSSAPIResponse{}
+	if err := Unmarshal(packet, userAuthGSSAPIResp); err != nil {
+		return authFailure, nil, err
+	}
+	// Start the loop into the exchange token.
+	// See RFC 4462 section 3.4.
+	var token []byte
+	defer g.gssAPIClient.DeleteSecContext()
+	for {
+		// Initiates the establishment of a security context between the application and a remote peer.
+		nextToken, needContinue, err := g.gssAPIClient.InitSecContext("host@"+g.target, token, false)
+		if err != nil {
+			return authFailure, nil, err
+		}
+		if len(nextToken) > 0 {
+			if err := c.writePacket(Marshal(&userAuthGSSAPIToken{
+				Token: nextToken,
+			})); err != nil {
+				return authFailure, nil, err
+			}
+		}
+		if !needContinue {
+			break
+		}
+		packet, err = c.readPacket()
+		if err != nil {
+			return authFailure, nil, err
+		}
+		switch packet[0] {
+		case msgUserAuthFailure:
+			var msg userAuthFailureMsg
+			if err := Unmarshal(packet, &msg); err != nil {
+				return authFailure, nil, err
+			}
+			if msg.PartialSuccess {
+				return authPartialSuccess, msg.Methods, nil
+			}
+			return authFailure, msg.Methods, nil
+		case msgUserAuthGSSAPIError:
+			userAuthGSSAPIErrorResp := &userAuthGSSAPIError{}
+			if err := Unmarshal(packet, userAuthGSSAPIErrorResp); err != nil {
+				return authFailure, nil, err
+			}
+			return authFailure, nil, fmt.Errorf("GSS-API Error:\n"+
+				"Major Status: %d\n"+
+				"Minor Status: %d\n"+
+				"Error Message: %s\n", userAuthGSSAPIErrorResp.MajorStatus, userAuthGSSAPIErrorResp.MinorStatus,
+				userAuthGSSAPIErrorResp.Message)
+		case msgUserAuthGSSAPIToken:
+			userAuthGSSAPITokenReq := &userAuthGSSAPIToken{}
+			if err := Unmarshal(packet, userAuthGSSAPITokenReq); err != nil {
+				return authFailure, nil, err
+			}
+			token = userAuthGSSAPITokenReq.Token
+		}
+	}
+	// Binding Encryption Keys.
+	// See RFC 4462 section 3.5.
+	micField := buildMIC(string(session), user, "ssh-connection", "gssapi-with-mic")
+	micToken, err := g.gssAPIClient.GetMIC(micField)
+	if err != nil {
+		return authFailure, nil, err
+	}
+	if err := c.writePacket(Marshal(&userAuthGSSAPIMIC{
+		MIC: micToken,
+	})); err != nil {
+		return authFailure, nil, err
+	}
+	return handleAuthResponse(c)
+}
+
+func (g *gssAPIWithMICCallback) method() string {
+	return "gssapi-with-mic"
+}

vendor/golang.org/x/crypto/ssh/common.go

@@ -51,6 +51,13 @@ var supportedKexAlgos = []string{
 	kexAlgoDH14SHA1, kexAlgoDH1SHA1,
 }
 
+// serverForbiddenKexAlgos contains key exchange algorithms, that are forbidden
+// for the server half.
+var serverForbiddenKexAlgos = map[string]struct{}{
+	kexAlgoDHGEXSHA1:   {}, // server half implementation is only minimal to satisfy the automated tests
+	kexAlgoDHGEXSHA256: {}, // server half implementation is only minimal to satisfy the automated tests
+}
+
 // supportedHostKeyAlgos specifies the supported host-key algorithms (i.e. methods
 // of authenticating servers) in preference order.
 var supportedHostKeyAlgos = []string{

vendor/golang.org/x/crypto/ssh/kex.go

@@ -10,7 +10,9 @@ import (
 	"crypto/elliptic"
 	"crypto/rand"
 	"crypto/subtle"
+	"encoding/binary"
 	"errors"
+	"fmt"
 	"io"
 	"math/big"
 
@@ -24,6 +26,12 @@ const (
 	kexAlgoECDH384          = "ecdh-sha2-nistp384"
 	kexAlgoECDH521          = "ecdh-sha2-nistp521"
 	kexAlgoCurve25519SHA256 = "curve25519-sha256@libssh.org"
+
+	// For the following kex only the client half contains a production
+	// ready implementation. The server half only consists of a minimal
+	// implementation to satisfy the automated tests.
+	kexAlgoDHGEXSHA1   = "diffie-hellman-group-exchange-sha1"
+	kexAlgoDHGEXSHA256 = "diffie-hellman-group-exchange-sha256"
 )
 
 // kexResult captures the outcome of a key exchange.
@@ -402,6 +410,8 @@ func init() {
 	kexAlgoMap[kexAlgoECDH384] = &ecdh{elliptic.P384()}
 	kexAlgoMap[kexAlgoECDH256] = &ecdh{elliptic.P256()}
 	kexAlgoMap[kexAlgoCurve25519SHA256] = &curve25519sha256{}
+	kexAlgoMap[kexAlgoDHGEXSHA1] = &dhGEXSHA{hashFunc: crypto.SHA1}
+	kexAlgoMap[kexAlgoDHGEXSHA256] = &dhGEXSHA{hashFunc: crypto.SHA256}
 }
 
 // curve25519sha256 implements the curve25519-sha256@libssh.org key
@@ -538,3 +548,242 @@ func (kex *curve25519sha256) Server(c packetConn, rand io.Reader, magics *handsh
 		Hash:      crypto.SHA256,
 	}, nil
 }
+
+// dhGEXSHA implements the diffie-hellman-group-exchange-sha1 and
+// diffie-hellman-group-exchange-sha256 key agreement protocols,
+// as described in RFC 4419
+type dhGEXSHA struct {
+	g, p     *big.Int
+	hashFunc crypto.Hash
+}
+
+const numMRTests = 64
+
+const (
+	dhGroupExchangeMinimumBits   = 2048
+	dhGroupExchangePreferredBits = 2048
+	dhGroupExchangeMaximumBits   = 8192
+)
+
+func (gex *dhGEXSHA) diffieHellman(theirPublic, myPrivate *big.Int) (*big.Int, error) {
+	if theirPublic.Sign() <= 0 || theirPublic.Cmp(gex.p) >= 0 {
+		return nil, fmt.Errorf("ssh: DH parameter out of bounds")
+	}
+	return new(big.Int).Exp(theirPublic, myPrivate, gex.p), nil
+}
+
+func (gex *dhGEXSHA) Client(c packetConn, randSource io.Reader, magics *handshakeMagics) (*kexResult, error) {
+	// Send GexRequest
+	kexDHGexRequest := kexDHGexRequestMsg{
+		MinBits:      dhGroupExchangeMinimumBits,
+		PreferedBits: dhGroupExchangePreferredBits,
+		MaxBits:      dhGroupExchangeMaximumBits,
+	}
+	if err := c.writePacket(Marshal(&kexDHGexRequest)); err != nil {
+		return nil, err
+	}
+
+	// Receive GexGroup
+	packet, err := c.readPacket()
+	if err != nil {
+		return nil, err
+	}
+
+	var kexDHGexGroup kexDHGexGroupMsg
+	if err = Unmarshal(packet, &kexDHGexGroup); err != nil {
+		return nil, err
+	}
+
+	// reject if p's bit length < dhGroupExchangeMinimumBits or > dhGroupExchangeMaximumBits
+	if kexDHGexGroup.P.BitLen() < dhGroupExchangeMinimumBits || kexDHGexGroup.P.BitLen() > dhGroupExchangeMaximumBits {
+		return nil, fmt.Errorf("ssh: server-generated gex p is out of range (%d bits)", kexDHGexGroup.P.BitLen())
+	}
+
+	gex.p = kexDHGexGroup.P
+	gex.g = kexDHGexGroup.G
+
+	// Check if p is safe by verifing that p and (p-1)/2 are primes
+	one := big.NewInt(1)
+	var pHalf = &big.Int{}
+	pHalf.Rsh(gex.p, 1)
+	if !gex.p.ProbablyPrime(numMRTests) || !pHalf.ProbablyPrime(numMRTests) {
+		return nil, fmt.Errorf("ssh: server provided gex p is not safe")
+	}
+
+	// Check if g is safe by verifing that g > 1 and g < p - 1
+	var pMinusOne = &big.Int{}
+	pMinusOne.Sub(gex.p, one)
+	if gex.g.Cmp(one) != 1 && gex.g.Cmp(pMinusOne) != -1 {
+		return nil, fmt.Errorf("ssh: server provided gex g is not safe")
+	}
+
+	// Send GexInit
+	x, err := rand.Int(randSource, pHalf)
+	if err != nil {
+		return nil, err
+	}
+	X := new(big.Int).Exp(gex.g, x, gex.p)
+	kexDHGexInit := kexDHGexInitMsg{
+		X: X,
+	}
+	if err := c.writePacket(Marshal(&kexDHGexInit)); err != nil {
+		return nil, err
+	}
+
+	// Receive GexReply
+	packet, err = c.readPacket()
+	if err != nil {
+		return nil, err
+	}
+
+	var kexDHGexReply kexDHGexReplyMsg
+	if err = Unmarshal(packet, &kexDHGexReply); err != nil {
+		return nil, err
+	}
+
+	kInt, err := gex.diffieHellman(kexDHGexReply.Y, x)
+	if err != nil {
+		return nil, err
+	}
+
+	// Check if k is safe by verifing that k > 1 and k < p - 1
+	if kInt.Cmp(one) != 1 && kInt.Cmp(pMinusOne) != -1 {
+		return nil, fmt.Errorf("ssh: derived k is not safe")
+	}
+
+	h := gex.hashFunc.New()
+	magics.write(h)
+	writeString(h, kexDHGexReply.HostKey)
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangeMinimumBits))
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangePreferredBits))
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangeMaximumBits))
+	writeInt(h, gex.p)
+	writeInt(h, gex.g)
+	writeInt(h, X)
+	writeInt(h, kexDHGexReply.Y)
+	K := make([]byte, intLength(kInt))
+	marshalInt(K, kInt)
+	h.Write(K)
+
+	return &kexResult{
+		H:         h.Sum(nil),
+		K:         K,
+		HostKey:   kexDHGexReply.HostKey,
+		Signature: kexDHGexReply.Signature,
+		Hash:      gex.hashFunc,
+	}, nil
+}
+
+// Server half implementation of the Diffie Hellman Key Exchange with SHA1 and SHA256.
+//
+// This is a minimal implementation to satisfy the automated tests.
+func (gex *dhGEXSHA) Server(c packetConn, randSource io.Reader, magics *handshakeMagics, priv Signer) (result *kexResult, err error) {
+	// Receive GexRequest
+	packet, err := c.readPacket()
+	if err != nil {
+		return
+	}
+	var kexDHGexRequest kexDHGexRequestMsg
+	if err = Unmarshal(packet, &kexDHGexRequest); err != nil {
+		return
+	}
+
+	// smoosh the user's preferred size into our own limits
+	if kexDHGexRequest.PreferedBits > dhGroupExchangeMaximumBits {
+		kexDHGexRequest.PreferedBits = dhGroupExchangeMaximumBits
+	}
+	if kexDHGexRequest.PreferedBits < dhGroupExchangeMinimumBits {
+		kexDHGexRequest.PreferedBits = dhGroupExchangeMinimumBits
+	}
+	// fix min/max if they're inconsistent.  technically, we could just pout
+	// and hang up, but there's no harm in giving them the benefit of the
+	// doubt and just picking a bitsize for them.
+	if kexDHGexRequest.MinBits > kexDHGexRequest.PreferedBits {
+		kexDHGexRequest.MinBits = kexDHGexRequest.PreferedBits
+	}
+	if kexDHGexRequest.MaxBits < kexDHGexRequest.PreferedBits {
+		kexDHGexRequest.MaxBits = kexDHGexRequest.PreferedBits
+	}
+
+	// Send GexGroup
+	// This is the group called diffie-hellman-group14-sha1 in RFC
+	// 4253 and Oakley Group 14 in RFC 3526.
+	p, _ := new(big.Int).SetString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
+	gex.p = p
+	gex.g = big.NewInt(2)
+
+	kexDHGexGroup := kexDHGexGroupMsg{
+		P: gex.p,
+		G: gex.g,
+	}
+	if err := c.writePacket(Marshal(&kexDHGexGroup)); err != nil {
+		return nil, err
+	}
+
+	// Receive GexInit
+	packet, err = c.readPacket()
+	if err != nil {
+		return
+	}
+	var kexDHGexInit kexDHGexInitMsg
+	if err = Unmarshal(packet, &kexDHGexInit); err != nil {
+		return
+	}
+
+	var pHalf = &big.Int{}
+	pHalf.Rsh(gex.p, 1)
+
+	y, err := rand.Int(randSource, pHalf)
+	if err != nil {
+		return
+	}
+
+	Y := new(big.Int).Exp(gex.g, y, gex.p)
+	kInt, err := gex.diffieHellman(kexDHGexInit.X, y)
+	if err != nil {
+		return nil, err
+	}
+
+	hostKeyBytes := priv.PublicKey().Marshal()
+
+	h := gex.hashFunc.New()
+	magics.write(h)
+	writeString(h, hostKeyBytes)
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangeMinimumBits))
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangePreferredBits))
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangeMaximumBits))
+	writeInt(h, gex.p)
+	writeInt(h, gex.g)
+	writeInt(h, kexDHGexInit.X)
+	writeInt(h, Y)
+
+	K := make([]byte, intLength(kInt))
+	marshalInt(K, kInt)
+	h.Write(K)
+
+	H := h.Sum(nil)
+
+	// H is already a hash, but the hostkey signing will apply its
+	// own key-specific hash algorithm.
+	sig, err := signAndMarshal(priv, randSource, H)
+	if err != nil {
+		return nil, err
+	}
+
+	kexDHGexReply := kexDHGexReplyMsg{
+		HostKey:   hostKeyBytes,
+		Y:         Y,
+		Signature: sig,
+	}
+	packet = Marshal(&kexDHGexReply)
+
+	err = c.writePacket(packet)
+
+	return &kexResult{
+		H:         H,
+		K:         K,
+		HostKey:   hostKeyBytes,
+		Signature: sig,
+		Hash:      gex.hashFunc,
+	}, err
+}

vendor/golang.org/x/crypto/ssh/messages.go

@@ -97,6 +97,36 @@ type kexDHReplyMsg struct {
 	Signature []byte
 }
 
+// See RFC 4419, section 5.
+const msgKexDHGexGroup = 31
+
+type kexDHGexGroupMsg struct {
+	P *big.Int `sshtype:"31"`
+	G *big.Int
+}
+
+const msgKexDHGexInit = 32
+
+type kexDHGexInitMsg struct {
+	X *big.Int `sshtype:"32"`
+}
+
+const msgKexDHGexReply = 33
+
+type kexDHGexReplyMsg struct {
+	HostKey   []byte `sshtype:"33"`
+	Y         *big.Int
+	Signature []byte
+}
+
+const msgKexDHGexRequest = 34
+
+type kexDHGexRequestMsg struct {
+	MinBits      uint32 `sshtype:"34"`
+	PreferedBits uint32
+	MaxBits      uint32
+}
+
 // See RFC 4253, section 10.
 const msgServiceRequest = 5
 
@@ -275,6 +305,42 @@ type userAuthPubKeyOkMsg struct {
 	PubKey []byte
 }
 
+// See RFC 4462, section 3
+const msgUserAuthGSSAPIResponse = 60
+
+type userAuthGSSAPIResponse struct {
+	SupportMech []byte `sshtype:"60"`
+}
+
+const msgUserAuthGSSAPIToken = 61
+
+type userAuthGSSAPIToken struct {
+	Token []byte `sshtype:"61"`
+}
+
+const msgUserAuthGSSAPIMIC = 66
+
+type userAuthGSSAPIMIC struct {
+	MIC []byte `sshtype:"66"`
+}
+
+// See RFC 4462, section 3.9
+const msgUserAuthGSSAPIErrTok = 64
+
+type userAuthGSSAPIErrTok struct {
+	ErrorToken []byte `sshtype:"64"`
+}
+
+// See RFC 4462, section 3.8
+const msgUserAuthGSSAPIError = 65
+
+type userAuthGSSAPIError struct {
+	MajorStatus uint32 `sshtype:"65"`
+	MinorStatus uint32
+	Message     string
+	LanguageTag string
+}
+
 // typeTags returns the possible type bytes for the given reflect.Type, which
 // should be a struct. The possible values are separated by a '|' character.
 func typeTags(structType reflect.Type) (tags []byte) {
@@ -756,6 +822,14 @@ func decode(packet []byte) (interface{}, error) {
 		msg = new(channelRequestSuccessMsg)
 	case msgChannelFailure:
 		msg = new(channelRequestFailureMsg)
+	case msgUserAuthGSSAPIToken:
+		msg = new(userAuthGSSAPIToken)
+	case msgUserAuthGSSAPIMIC:
+		msg = new(userAuthGSSAPIMIC)
+	case msgUserAuthGSSAPIErrTok:
+		msg = new(userAuthGSSAPIErrTok)
+	case msgUserAuthGSSAPIError:
+		msg = new(userAuthGSSAPIError)
 	default:
 		return nil, unexpectedMessageError(0, packet[0])
 	}

vendor/golang.org/x/crypto/ssh/server.go

@@ -45,6 +45,20 @@ type Permissions struct {
 	Extensions map[string]string
 }
 
+type GSSAPIWithMICConfig struct {
+	// AllowLogin, must be set, is called when gssapi-with-mic
+	// authentication is selected (RFC 4462 section 3). The srcName is from the
+	// results of the GSS-API authentication. The format is username@DOMAIN.
+	// GSSAPI just guarantees to the server who the user is, but not if they can log in, and with what permissions.
+	// This callback is called after the user identity is established with GSSAPI to decide if the user can login with
+	// which permissions. If the user is allowed to login, it should return a nil error.
+	AllowLogin func(conn ConnMetadata, srcName string) (*Permissions, error)
+
+	// Server must be set. It's the implementation
+	// of the GSSAPIServer interface. See GSSAPIServer interface for details.
+	Server GSSAPIServer
+}
+
 // ServerConfig holds server specific configuration data.
 type ServerConfig struct {
 	// Config contains configuration shared between client and server.
@@ -99,6 +113,10 @@ type ServerConfig struct {
 	// BannerCallback, if present, is called and the return string is sent to
 	// the client after key exchange completed but before authentication.
 	BannerCallback func(conn ConnMetadata) string
+
+	// GSSAPIWithMICConfig includes gssapi server and callback, which if both non-nil, is used
+	// when gssapi-with-mic authentication is selected (RFC 4462 section 3).
+	GSSAPIWithMICConfig *GSSAPIWithMICConfig
 }
 
 // AddHostKey adds a private key as a host key. If an existing host
@@ -175,6 +193,12 @@ func NewServerConn(c net.Conn, config *ServerConfig) (*ServerConn, <-chan NewCha
 	if fullConf.MaxAuthTries == 0 {
 		fullConf.MaxAuthTries = 6
 	}
+	// Check if the config contains any unsupported key exchanges
+	for _, kex := range fullConf.KeyExchanges {
+		if _, ok := serverForbiddenKexAlgos[kex]; ok {
+			return nil, nil, nil, fmt.Errorf("ssh: unsupported key exchange %s for server", kex)
+		}
+	}
 
 	s := &connection{
 		sshConn: sshConn{conn: c},
@@ -204,7 +228,9 @@ func (s *connection) serverHandshake(config *ServerConfig) (*Permissions, error)
 		return nil, errors.New("ssh: server has no host keys")
 	}
 
-	if !config.NoClientAuth && config.PasswordCallback == nil && config.PublicKeyCallback == nil && config.KeyboardInteractiveCallback == nil {
+	if !config.NoClientAuth && config.PasswordCallback == nil && config.PublicKeyCallback == nil &&
+		config.KeyboardInteractiveCallback == nil && (config.GSSAPIWithMICConfig == nil ||
+		config.GSSAPIWithMICConfig.AllowLogin == nil || config.GSSAPIWithMICConfig.Server == nil) {
 		return nil, errors.New("ssh: no authentication methods configured but NoClientAuth is also false")
 	}
 
@@ -295,6 +321,55 @@ func checkSourceAddress(addr net.Addr, sourceAddrs string) error {
 	return fmt.Errorf("ssh: remote address %v is not allowed because of source-address restriction", addr)
 }
 
+func gssExchangeToken(gssapiConfig *GSSAPIWithMICConfig, firstToken []byte, s *connection,
+	sessionID []byte, userAuthReq userAuthRequestMsg) (authErr error, perms *Permissions, err error) {
+	gssAPIServer := gssapiConfig.Server
+	defer gssAPIServer.DeleteSecContext()
+	var srcName string
+	for {
+		var (
+			outToken     []byte
+			needContinue bool
+		)
+		outToken, srcName, needContinue, err = gssAPIServer.AcceptSecContext(firstToken)
+		if err != nil {
+			return err, nil, nil
+		}
+		if len(outToken) != 0 {
+			if err := s.transport.writePacket(Marshal(&userAuthGSSAPIToken{
+				Token: outToken,
+			})); err != nil {
+				return nil, nil, err
+			}
+		}
+		if !needContinue {
+			break
+		}
+		packet, err := s.transport.readPacket()
+		if err != nil {
+			return nil, nil, err
+		}
+		userAuthGSSAPITokenReq := &userAuthGSSAPIToken{}
+		if err := Unmarshal(packet, userAuthGSSAPITokenReq); err != nil {
+			return nil, nil, err
+		}
+	}
+	packet, err := s.transport.readPacket()
+	if err != nil {
+		return nil, nil, err
+	}
+	userAuthGSSAPIMICReq := &userAuthGSSAPIMIC{}
+	if err := Unmarshal(packet, userAuthGSSAPIMICReq); err != nil {
+		return nil, nil, err
+	}
+	mic := buildMIC(string(sessionID), userAuthReq.User, userAuthReq.Service, userAuthReq.Method)
+	if err := gssAPIServer.VerifyMIC(mic, userAuthGSSAPIMICReq.MIC); err != nil {
+		return err, nil, nil
+	}
+	perms, authErr = gssapiConfig.AllowLogin(s, srcName)
+	return authErr, perms, nil
+}
+
 // ServerAuthError represents server authentication errors and is
 // sometimes returned by NewServerConn. It appends any authentication
 // errors that may occur, and is returned if all of the authentication
@@ -496,6 +571,49 @@ userAuthLoop:
 				authErr = candidate.result
 				perms = candidate.perms
 			}
+		case "gssapi-with-mic":
+			gssapiConfig := config.GSSAPIWithMICConfig
+			userAuthRequestGSSAPI, err := parseGSSAPIPayload(userAuthReq.Payload)
+			if err != nil {
+				return nil, parseError(msgUserAuthRequest)
+			}
+			// OpenSSH supports Kerberos V5 mechanism only for GSS-API authentication.
+			if userAuthRequestGSSAPI.N == 0 {
+				authErr = fmt.Errorf("ssh: Mechanism negotiation is not supported")
+				break
+			}
+			var i uint32
+			present := false
+			for i = 0; i < userAuthRequestGSSAPI.N; i++ {
+				if userAuthRequestGSSAPI.OIDS[i].Equal(krb5Mesh) {
+					present = true
+					break
+				}
+			}
+			if !present {
+				authErr = fmt.Errorf("ssh: GSSAPI authentication must use the Kerberos V5 mechanism")
+				break
+			}
+			// Initial server response, see RFC 4462 section 3.3.
+			if err := s.transport.writePacket(Marshal(&userAuthGSSAPIResponse{
+				SupportMech: krb5OID,
+			})); err != nil {
+				return nil, err
+			}
+			// Exchange token, see RFC 4462 section 3.4.
+			packet, err := s.transport.readPacket()
+			if err != nil {
+				return nil, err
+			}
+			userAuthGSSAPITokenReq := &userAuthGSSAPIToken{}
+			if err := Unmarshal(packet, userAuthGSSAPITokenReq); err != nil {
+				return nil, err
+			}
+			authErr, perms, err = gssExchangeToken(gssapiConfig, userAuthGSSAPITokenReq.Token, s, sessionID,
+				userAuthReq)
+			if err != nil {
+				return nil, err
+			}
 		default:
 			authErr = fmt.Errorf("ssh: unknown method %q", userAuthReq.Method)
 		}
@@ -522,6 +640,10 @@ userAuthLoop:
 		if config.KeyboardInteractiveCallback != nil {
 			failureMsg.Methods = append(failureMsg.Methods, "keyboard-interactive")
 		}
+		if config.GSSAPIWithMICConfig != nil && config.GSSAPIWithMICConfig.Server != nil &&
+			config.GSSAPIWithMICConfig.AllowLogin != nil {
+			failureMsg.Methods = append(failureMsg.Methods, "gssapi-with-mic")
+		}
 
 		if len(failureMsg.Methods) == 0 {
 			return nil, errors.New("ssh: no authentication methods configured but NoClientAuth is also false")

vendor/golang.org/x/crypto/ssh/ssh_gss.go

@@ -0,0 +1,139 @@
+// Copyright 2011 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 ssh
+
+import (
+	"encoding/asn1"
+	"errors"
+)
+
+var krb5OID []byte
+
+func init() {
+	krb5OID, _ = asn1.Marshal(krb5Mesh)
+}
+
+// GSSAPIClient provides the API to plug-in GSSAPI authentication for client logins.
+type GSSAPIClient interface {
+	// InitSecContext initiates the establishment of a security context for GSS-API between the
+	// ssh client and ssh server. Initially the token parameter should be specified as nil.
+	// The routine may return a outputToken which should be transferred to
+	// the ssh server, where the ssh server will present it to
+	// AcceptSecContext. If no token need be sent, InitSecContext will indicate this by setting
+	// needContinue to false. To complete the context
+	// establishment, one or more reply tokens may be required from the ssh
+	// server;if so, InitSecContext will return a needContinue which is true.
+	// In this case, InitSecContext should be called again when the
+	// reply token is received from the ssh server, passing the reply
+	// token to InitSecContext via the token parameters.
+	// See RFC 2743 section 2.2.1 and RFC 4462 section 3.4.
+	InitSecContext(target string, token []byte, isGSSDelegCreds bool) (outputToken []byte, needContinue bool, err error)
+	// GetMIC generates a cryptographic MIC for the SSH2 message, and places
+	// the MIC in a token for transfer to the ssh server.
+	// The contents of the MIC field are obtained by calling GSS_GetMIC()
+	// over the following, using the GSS-API context that was just
+	// established:
+	//  string    session identifier
+	//  byte      SSH_MSG_USERAUTH_REQUEST
+	//  string    user name
+	//  string    service
+	//  string    "gssapi-with-mic"
+	// See RFC 2743 section 2.3.1 and RFC 4462 3.5.
+	GetMIC(micFiled []byte) ([]byte, error)
+	// Whenever possible, it should be possible for
+	// DeleteSecContext() calls to be successfully processed even
+	// if other calls cannot succeed, thereby enabling context-related
+	// resources to be released.
+	// In addition to deleting established security contexts,
+	// gss_delete_sec_context must also be able to delete "half-built"
+	// security contexts resulting from an incomplete sequence of
+	// InitSecContext()/AcceptSecContext() calls.
+	// See RFC 2743 section 2.2.3.
+	DeleteSecContext() error
+}
+
+// GSSAPIServer provides the API to plug in GSSAPI authentication for server logins.
+type GSSAPIServer interface {
+	// AcceptSecContext allows a remotely initiated security context between the application
+	// and a remote peer to be established by the ssh client. The routine may return a
+	// outputToken which should be transferred to the ssh client,
+	// where the ssh client will present it to InitSecContext.
+	// If no token need be sent, AcceptSecContext will indicate this
+	// by setting the needContinue to false. To
+	// complete the context establishment, one or more reply tokens may be
+	// required from the ssh client. if so, AcceptSecContext
+	// will return a needContinue which is true, in which case it
+	// should be called again when the reply token is received from the ssh
+	// client, passing the token to AcceptSecContext via the
+	// token parameters.
+	// The srcName return value is the authenticated username.
+	// See RFC 2743 section 2.2.2 and RFC 4462 section 3.4.
+	AcceptSecContext(token []byte) (outputToken []byte, srcName string, needContinue bool, err error)
+	// VerifyMIC verifies that a cryptographic MIC, contained in the token parameter,
+	// fits the supplied message is received from the ssh client.
+	// See RFC 2743 section 2.3.2.
+	VerifyMIC(micField []byte, micToken []byte) error
+	// Whenever possible, it should be possible for
+	// DeleteSecContext() calls to be successfully processed even
+	// if other calls cannot succeed, thereby enabling context-related
+	// resources to be released.
+	// In addition to deleting established security contexts,
+	// gss_delete_sec_context must also be able to delete "half-built"
+	// security contexts resulting from an incomplete sequence of
+	// InitSecContext()/AcceptSecContext() calls.
+	// See RFC 2743 section 2.2.3.
+	DeleteSecContext() error
+}
+
+var (
+	// OpenSSH supports Kerberos V5 mechanism only for GSS-API authentication,
+	// so we also support the krb5 mechanism only.
+	// See RFC 1964 section 1.
+	krb5Mesh = asn1.ObjectIdentifier{1, 2, 840, 113554, 1, 2, 2}
+)
+
+// The GSS-API authentication method is initiated when the client sends an SSH_MSG_USERAUTH_REQUEST
+// See RFC 4462 section 3.2.
+type userAuthRequestGSSAPI struct {
+	N    uint32
+	OIDS []asn1.ObjectIdentifier
+}
+
+func parseGSSAPIPayload(payload []byte) (*userAuthRequestGSSAPI, error) {
+	n, rest, ok := parseUint32(payload)
+	if !ok {
+		return nil, errors.New("parse uint32 failed")
+	}
+	s := &userAuthRequestGSSAPI{
+		N:    n,
+		OIDS: make([]asn1.ObjectIdentifier, n),
+	}
+	for i := 0; i < int(n); i++ {
+		var (
+			desiredMech []byte
+			err         error
+		)
+		desiredMech, rest, ok = parseString(rest)
+		if !ok {
+			return nil, errors.New("parse string failed")
+		}
+		if rest, err = asn1.Unmarshal(desiredMech, &s.OIDS[i]); err != nil {
+			return nil, err
+		}
+
+	}
+	return s, nil
+}
+
+// See RFC 4462 section 3.6.
+func buildMIC(sessionID string, username string, service string, authMethod string) []byte {
+	out := make([]byte, 0, 0)
+	out = appendString(out, sessionID)
+	out = append(out, msgUserAuthRequest)
+	out = appendString(out, username)
+	out = appendString(out, service)
+	out = appendString(out, authMethod)
+	return out
+}

vendor/modules.txt

@@ -485,7 +485,7 @@ go.opencensus.io/trace/propagation
 go.opencensus.io
 go.opencensus.io/stats/internal
 go.opencensus.io/internal/tagencoding
-# golang.org/x/crypto v0.0.0-20190426145343-a29dc8fdc734
+# golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4
 golang.org/x/crypto/ssh
 golang.org/x/crypto/ssh/agent
 golang.org/x/crypto/ssh/knownhosts