850 lines
21 KiB
Go
850 lines
21 KiB
Go
// Copyright 2010 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// TLS low level connection and record layer
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package tls
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import (
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"bytes"
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"crypto/cipher"
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"crypto/subtle"
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"crypto/x509"
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"errors"
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"io"
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"net"
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"sync"
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)
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// A Conn represents a secured connection.
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// It implements the net.Conn interface.
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type Conn struct {
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// constant
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conn net.Conn
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isClient bool
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// constant after handshake; protected by handshakeMutex
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handshakeMutex sync.Mutex // handshakeMutex < in.Mutex, out.Mutex, errMutex
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vers uint16 // TLS version
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haveVers bool // version has been negotiated
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config *Config // configuration passed to constructor
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handshakeComplete bool
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cipherSuite uint16
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ocspResponse []byte // stapled OCSP response
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peerCertificates []*x509.Certificate
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// verifiedChains contains the certificate chains that we built, as
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// opposed to the ones presented by the server.
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verifiedChains [][]*x509.Certificate
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// serverName contains the server name indicated by the client, if any.
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serverName string
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clientProtocol string
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clientProtocolFallback bool
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// first permanent error
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errMutex sync.Mutex
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err error
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// input/output
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in, out halfConn // in.Mutex < out.Mutex
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rawInput *block // raw input, right off the wire
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input *block // application data waiting to be read
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hand bytes.Buffer // handshake data waiting to be read
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tmp [16]byte
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}
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func (c *Conn) setError(err error) error {
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c.errMutex.Lock()
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defer c.errMutex.Unlock()
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if c.err == nil {
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c.err = err
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}
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return err
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}
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func (c *Conn) error() error {
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c.errMutex.Lock()
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defer c.errMutex.Unlock()
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return c.err
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}
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// Access to net.Conn methods.
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// Cannot just embed net.Conn because that would
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// export the struct field too.
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// LocalAddr returns the local network address.
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func (c *Conn) LocalAddr() net.Addr {
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return c.conn.LocalAddr()
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}
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// RemoteAddr returns the remote network address.
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func (c *Conn) RemoteAddr() net.Addr {
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return c.conn.RemoteAddr()
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}
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// SetTimeout sets the read deadline associated with the connection.
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// There is no write deadline.
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func (c *Conn) SetTimeout(nsec int64) error {
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return c.conn.SetTimeout(nsec)
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}
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// SetReadTimeout sets the time (in nanoseconds) that
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// Read will wait for data before returning a net.Error
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// with Timeout() == true.
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// Setting nsec == 0 (the default) disables the deadline.
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func (c *Conn) SetReadTimeout(nsec int64) error {
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return c.conn.SetReadTimeout(nsec)
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}
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// SetWriteTimeout exists to satisfy the net.Conn interface
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// but is not implemented by TLS. It always returns an error.
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func (c *Conn) SetWriteTimeout(nsec int64) error {
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return errors.New("TLS does not support SetWriteTimeout")
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}
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// A halfConn represents one direction of the record layer
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// connection, either sending or receiving.
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type halfConn struct {
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sync.Mutex
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version uint16 // protocol version
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cipher interface{} // cipher algorithm
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mac macFunction
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seq [8]byte // 64-bit sequence number
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bfree *block // list of free blocks
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nextCipher interface{} // next encryption state
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nextMac macFunction // next MAC algorithm
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// used to save allocating a new buffer for each MAC.
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inDigestBuf, outDigestBuf []byte
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}
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// prepareCipherSpec sets the encryption and MAC states
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// that a subsequent changeCipherSpec will use.
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func (hc *halfConn) prepareCipherSpec(version uint16, cipher interface{}, mac macFunction) {
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hc.version = version
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hc.nextCipher = cipher
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hc.nextMac = mac
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}
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// changeCipherSpec changes the encryption and MAC states
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// to the ones previously passed to prepareCipherSpec.
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func (hc *halfConn) changeCipherSpec() error {
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if hc.nextCipher == nil {
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return alertInternalError
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}
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hc.cipher = hc.nextCipher
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hc.mac = hc.nextMac
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hc.nextCipher = nil
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hc.nextMac = nil
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return nil
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}
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// incSeq increments the sequence number.
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func (hc *halfConn) incSeq() {
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for i := 7; i >= 0; i-- {
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hc.seq[i]++
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if hc.seq[i] != 0 {
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return
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}
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}
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// Not allowed to let sequence number wrap.
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// Instead, must renegotiate before it does.
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// Not likely enough to bother.
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panic("TLS: sequence number wraparound")
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}
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// resetSeq resets the sequence number to zero.
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func (hc *halfConn) resetSeq() {
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for i := range hc.seq {
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hc.seq[i] = 0
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}
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}
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// removePadding returns an unpadded slice, in constant time, which is a prefix
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// of the input. It also returns a byte which is equal to 255 if the padding
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// was valid and 0 otherwise. See RFC 2246, section 6.2.3.2
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func removePadding(payload []byte) ([]byte, byte) {
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if len(payload) < 1 {
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return payload, 0
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}
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paddingLen := payload[len(payload)-1]
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t := uint(len(payload)-1) - uint(paddingLen)
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// if len(payload) >= (paddingLen - 1) then the MSB of t is zero
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good := byte(int32(^t) >> 31)
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toCheck := 255 // the maximum possible padding length
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// The length of the padded data is public, so we can use an if here
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if toCheck+1 > len(payload) {
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toCheck = len(payload) - 1
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}
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for i := 0; i < toCheck; i++ {
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t := uint(paddingLen) - uint(i)
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// if i <= paddingLen then the MSB of t is zero
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mask := byte(int32(^t) >> 31)
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b := payload[len(payload)-1-i]
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good &^= mask&paddingLen ^ mask&b
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}
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// We AND together the bits of good and replicate the result across
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// all the bits.
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good &= good << 4
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good &= good << 2
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good &= good << 1
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good = uint8(int8(good) >> 7)
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toRemove := good&paddingLen + 1
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return payload[:len(payload)-int(toRemove)], good
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}
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// removePaddingSSL30 is a replacement for removePadding in the case that the
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// protocol version is SSLv3. In this version, the contents of the padding
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// are random and cannot be checked.
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func removePaddingSSL30(payload []byte) ([]byte, byte) {
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if len(payload) < 1 {
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return payload, 0
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}
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paddingLen := int(payload[len(payload)-1]) + 1
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if paddingLen > len(payload) {
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return payload, 0
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}
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return payload[:len(payload)-paddingLen], 255
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}
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func roundUp(a, b int) int {
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return a + (b-a%b)%b
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}
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// decrypt checks and strips the mac and decrypts the data in b.
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func (hc *halfConn) decrypt(b *block) (bool, alert) {
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// pull out payload
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payload := b.data[recordHeaderLen:]
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macSize := 0
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if hc.mac != nil {
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macSize = hc.mac.Size()
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}
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paddingGood := byte(255)
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// decrypt
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if hc.cipher != nil {
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switch c := hc.cipher.(type) {
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case cipher.Stream:
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c.XORKeyStream(payload, payload)
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case cipher.BlockMode:
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blockSize := c.BlockSize()
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if len(payload)%blockSize != 0 || len(payload) < roundUp(macSize+1, blockSize) {
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return false, alertBadRecordMAC
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}
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c.CryptBlocks(payload, payload)
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if hc.version == versionSSL30 {
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payload, paddingGood = removePaddingSSL30(payload)
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} else {
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payload, paddingGood = removePadding(payload)
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}
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b.resize(recordHeaderLen + len(payload))
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// note that we still have a timing side-channel in the
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// MAC check, below. An attacker can align the record
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// so that a correct padding will cause one less hash
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// block to be calculated. Then they can iteratively
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// decrypt a record by breaking each byte. See
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// "Password Interception in a SSL/TLS Channel", Brice
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// Canvel et al.
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//
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// However, our behavior matches OpenSSL, so we leak
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// only as much as they do.
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default:
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panic("unknown cipher type")
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}
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}
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// check, strip mac
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if hc.mac != nil {
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if len(payload) < macSize {
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return false, alertBadRecordMAC
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}
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// strip mac off payload, b.data
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n := len(payload) - macSize
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b.data[3] = byte(n >> 8)
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b.data[4] = byte(n)
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b.resize(recordHeaderLen + n)
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remoteMAC := payload[n:]
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localMAC := hc.mac.MAC(hc.inDigestBuf, hc.seq[0:], b.data)
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hc.incSeq()
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if subtle.ConstantTimeCompare(localMAC, remoteMAC) != 1 || paddingGood != 255 {
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return false, alertBadRecordMAC
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}
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hc.inDigestBuf = localMAC
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}
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return true, 0
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}
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// padToBlockSize calculates the needed padding block, if any, for a payload.
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// On exit, prefix aliases payload and extends to the end of the last full
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// block of payload. finalBlock is a fresh slice which contains the contents of
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// any suffix of payload as well as the needed padding to make finalBlock a
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// full block.
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func padToBlockSize(payload []byte, blockSize int) (prefix, finalBlock []byte) {
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overrun := len(payload) % blockSize
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paddingLen := blockSize - overrun
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prefix = payload[:len(payload)-overrun]
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finalBlock = make([]byte, blockSize)
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copy(finalBlock, payload[len(payload)-overrun:])
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for i := overrun; i < blockSize; i++ {
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finalBlock[i] = byte(paddingLen - 1)
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}
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return
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}
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// encrypt encrypts and macs the data in b.
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func (hc *halfConn) encrypt(b *block) (bool, alert) {
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// mac
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if hc.mac != nil {
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mac := hc.mac.MAC(hc.outDigestBuf, hc.seq[0:], b.data)
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hc.incSeq()
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n := len(b.data)
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b.resize(n + len(mac))
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copy(b.data[n:], mac)
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hc.outDigestBuf = mac
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}
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payload := b.data[recordHeaderLen:]
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// encrypt
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if hc.cipher != nil {
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switch c := hc.cipher.(type) {
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case cipher.Stream:
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c.XORKeyStream(payload, payload)
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case cipher.BlockMode:
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prefix, finalBlock := padToBlockSize(payload, c.BlockSize())
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b.resize(recordHeaderLen + len(prefix) + len(finalBlock))
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c.CryptBlocks(b.data[recordHeaderLen:], prefix)
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c.CryptBlocks(b.data[recordHeaderLen+len(prefix):], finalBlock)
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default:
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panic("unknown cipher type")
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}
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}
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// update length to include MAC and any block padding needed.
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n := len(b.data) - recordHeaderLen
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b.data[3] = byte(n >> 8)
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b.data[4] = byte(n)
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return true, 0
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}
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// A block is a simple data buffer.
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type block struct {
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data []byte
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off int // index for Read
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link *block
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}
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// resize resizes block to be n bytes, growing if necessary.
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func (b *block) resize(n int) {
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if n > cap(b.data) {
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b.reserve(n)
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}
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b.data = b.data[0:n]
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}
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// reserve makes sure that block contains a capacity of at least n bytes.
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func (b *block) reserve(n int) {
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if cap(b.data) >= n {
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return
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}
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m := cap(b.data)
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if m == 0 {
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m = 1024
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}
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for m < n {
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m *= 2
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}
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data := make([]byte, len(b.data), m)
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copy(data, b.data)
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b.data = data
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}
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// readFromUntil reads from r into b until b contains at least n bytes
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// or else returns an error.
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func (b *block) readFromUntil(r io.Reader, n int) error {
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// quick case
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if len(b.data) >= n {
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return nil
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}
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// read until have enough.
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b.reserve(n)
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for {
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m, err := r.Read(b.data[len(b.data):cap(b.data)])
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b.data = b.data[0 : len(b.data)+m]
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if len(b.data) >= n {
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break
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}
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if err != nil {
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return err
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}
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}
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return nil
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}
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func (b *block) Read(p []byte) (n int, err error) {
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n = copy(p, b.data[b.off:])
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b.off += n
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return
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}
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// newBlock allocates a new block, from hc's free list if possible.
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func (hc *halfConn) newBlock() *block {
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b := hc.bfree
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if b == nil {
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return new(block)
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}
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hc.bfree = b.link
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b.link = nil
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b.resize(0)
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return b
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}
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// freeBlock returns a block to hc's free list.
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// The protocol is such that each side only has a block or two on
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// its free list at a time, so there's no need to worry about
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// trimming the list, etc.
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func (hc *halfConn) freeBlock(b *block) {
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b.link = hc.bfree
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hc.bfree = b
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}
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// splitBlock splits a block after the first n bytes,
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// returning a block with those n bytes and a
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// block with the remainder. the latter may be nil.
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func (hc *halfConn) splitBlock(b *block, n int) (*block, *block) {
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if len(b.data) <= n {
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return b, nil
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}
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bb := hc.newBlock()
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bb.resize(len(b.data) - n)
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copy(bb.data, b.data[n:])
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b.data = b.data[0:n]
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return b, bb
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}
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// readRecord reads the next TLS record from the connection
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// and updates the record layer state.
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// c.in.Mutex <= L; c.input == nil.
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func (c *Conn) readRecord(want recordType) error {
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// Caller must be in sync with connection:
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// handshake data if handshake not yet completed,
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// else application data. (We don't support renegotiation.)
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switch want {
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default:
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return c.sendAlert(alertInternalError)
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case recordTypeHandshake, recordTypeChangeCipherSpec:
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if c.handshakeComplete {
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return c.sendAlert(alertInternalError)
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}
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case recordTypeApplicationData:
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if !c.handshakeComplete {
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return c.sendAlert(alertInternalError)
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}
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}
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Again:
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if c.rawInput == nil {
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c.rawInput = c.in.newBlock()
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}
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b := c.rawInput
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// Read header, payload.
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if err := b.readFromUntil(c.conn, recordHeaderLen); err != nil {
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// RFC suggests that EOF without an alertCloseNotify is
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// an error, but popular web sites seem to do this,
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// so we can't make it an error.
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// if err == io.EOF {
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// err = io.ErrUnexpectedEOF
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// }
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if e, ok := err.(net.Error); !ok || !e.Temporary() {
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c.setError(err)
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}
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return err
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}
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typ := recordType(b.data[0])
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vers := uint16(b.data[1])<<8 | uint16(b.data[2])
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n := int(b.data[3])<<8 | int(b.data[4])
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if c.haveVers && vers != c.vers {
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return c.sendAlert(alertProtocolVersion)
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}
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if n > maxCiphertext {
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return c.sendAlert(alertRecordOverflow)
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}
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if !c.haveVers {
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// First message, be extra suspicious:
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// this might not be a TLS client.
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// Bail out before reading a full 'body', if possible.
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// The current max version is 3.1.
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// If the version is >= 16.0, it's probably not real.
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// Similarly, a clientHello message encodes in
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// well under a kilobyte. If the length is >= 12 kB,
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// it's probably not real.
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if (typ != recordTypeAlert && typ != want) || vers >= 0x1000 || n >= 0x3000 {
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return c.sendAlert(alertUnexpectedMessage)
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}
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}
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if err := b.readFromUntil(c.conn, recordHeaderLen+n); err != nil {
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if err == io.EOF {
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err = io.ErrUnexpectedEOF
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}
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if e, ok := err.(net.Error); !ok || !e.Temporary() {
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c.setError(err)
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}
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return err
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}
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// Process message.
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b, c.rawInput = c.in.splitBlock(b, recordHeaderLen+n)
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b.off = recordHeaderLen
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if ok, err := c.in.decrypt(b); !ok {
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return c.sendAlert(err)
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}
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data := b.data[b.off:]
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if len(data) > maxPlaintext {
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c.sendAlert(alertRecordOverflow)
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c.in.freeBlock(b)
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return c.error()
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}
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switch typ {
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default:
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c.sendAlert(alertUnexpectedMessage)
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case recordTypeAlert:
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if len(data) != 2 {
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c.sendAlert(alertUnexpectedMessage)
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break
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}
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if alert(data[1]) == alertCloseNotify {
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c.setError(io.EOF)
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break
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}
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switch data[0] {
|
|
case alertLevelWarning:
|
|
// drop on the floor
|
|
c.in.freeBlock(b)
|
|
goto Again
|
|
case alertLevelError:
|
|
c.setError(&net.OpError{Op: "remote error", Err: alert(data[1])})
|
|
default:
|
|
c.sendAlert(alertUnexpectedMessage)
|
|
}
|
|
|
|
case recordTypeChangeCipherSpec:
|
|
if typ != want || len(data) != 1 || data[0] != 1 {
|
|
c.sendAlert(alertUnexpectedMessage)
|
|
break
|
|
}
|
|
err := c.in.changeCipherSpec()
|
|
if err != nil {
|
|
c.sendAlert(err.(alert))
|
|
}
|
|
|
|
case recordTypeApplicationData:
|
|
if typ != want {
|
|
c.sendAlert(alertUnexpectedMessage)
|
|
break
|
|
}
|
|
c.input = b
|
|
b = nil
|
|
|
|
case recordTypeHandshake:
|
|
// TODO(rsc): Should at least pick off connection close.
|
|
if typ != want {
|
|
return c.sendAlert(alertNoRenegotiation)
|
|
}
|
|
c.hand.Write(data)
|
|
}
|
|
|
|
if b != nil {
|
|
c.in.freeBlock(b)
|
|
}
|
|
return c.error()
|
|
}
|
|
|
|
// sendAlert sends a TLS alert message.
|
|
// c.out.Mutex <= L.
|
|
func (c *Conn) sendAlertLocked(err alert) error {
|
|
c.tmp[0] = alertLevelError
|
|
if err == alertNoRenegotiation {
|
|
c.tmp[0] = alertLevelWarning
|
|
}
|
|
c.tmp[1] = byte(err)
|
|
c.writeRecord(recordTypeAlert, c.tmp[0:2])
|
|
// closeNotify is a special case in that it isn't an error:
|
|
if err != alertCloseNotify {
|
|
return c.setError(&net.OpError{Op: "local error", Err: err})
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// sendAlert sends a TLS alert message.
|
|
// L < c.out.Mutex.
|
|
func (c *Conn) sendAlert(err alert) error {
|
|
c.out.Lock()
|
|
defer c.out.Unlock()
|
|
return c.sendAlertLocked(err)
|
|
}
|
|
|
|
// writeRecord writes a TLS record with the given type and payload
|
|
// to the connection and updates the record layer state.
|
|
// c.out.Mutex <= L.
|
|
func (c *Conn) writeRecord(typ recordType, data []byte) (n int, err error) {
|
|
b := c.out.newBlock()
|
|
for len(data) > 0 {
|
|
m := len(data)
|
|
if m > maxPlaintext {
|
|
m = maxPlaintext
|
|
}
|
|
b.resize(recordHeaderLen + m)
|
|
b.data[0] = byte(typ)
|
|
vers := c.vers
|
|
if vers == 0 {
|
|
vers = maxVersion
|
|
}
|
|
b.data[1] = byte(vers >> 8)
|
|
b.data[2] = byte(vers)
|
|
b.data[3] = byte(m >> 8)
|
|
b.data[4] = byte(m)
|
|
copy(b.data[recordHeaderLen:], data)
|
|
c.out.encrypt(b)
|
|
_, err = c.conn.Write(b.data)
|
|
if err != nil {
|
|
break
|
|
}
|
|
n += m
|
|
data = data[m:]
|
|
}
|
|
c.out.freeBlock(b)
|
|
|
|
if typ == recordTypeChangeCipherSpec {
|
|
err = c.out.changeCipherSpec()
|
|
if err != nil {
|
|
// Cannot call sendAlert directly,
|
|
// because we already hold c.out.Mutex.
|
|
c.tmp[0] = alertLevelError
|
|
c.tmp[1] = byte(err.(alert))
|
|
c.writeRecord(recordTypeAlert, c.tmp[0:2])
|
|
c.err = &net.OpError{Op: "local error", Err: err}
|
|
return n, c.err
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
// readHandshake reads the next handshake message from
|
|
// the record layer.
|
|
// c.in.Mutex < L; c.out.Mutex < L.
|
|
func (c *Conn) readHandshake() (interface{}, error) {
|
|
for c.hand.Len() < 4 {
|
|
if c.err != nil {
|
|
return nil, c.err
|
|
}
|
|
if err := c.readRecord(recordTypeHandshake); err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
|
|
data := c.hand.Bytes()
|
|
n := int(data[1])<<16 | int(data[2])<<8 | int(data[3])
|
|
if n > maxHandshake {
|
|
c.sendAlert(alertInternalError)
|
|
return nil, c.err
|
|
}
|
|
for c.hand.Len() < 4+n {
|
|
if c.err != nil {
|
|
return nil, c.err
|
|
}
|
|
if err := c.readRecord(recordTypeHandshake); err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
data = c.hand.Next(4 + n)
|
|
var m handshakeMessage
|
|
switch data[0] {
|
|
case typeClientHello:
|
|
m = new(clientHelloMsg)
|
|
case typeServerHello:
|
|
m = new(serverHelloMsg)
|
|
case typeCertificate:
|
|
m = new(certificateMsg)
|
|
case typeCertificateRequest:
|
|
m = new(certificateRequestMsg)
|
|
case typeCertificateStatus:
|
|
m = new(certificateStatusMsg)
|
|
case typeServerKeyExchange:
|
|
m = new(serverKeyExchangeMsg)
|
|
case typeServerHelloDone:
|
|
m = new(serverHelloDoneMsg)
|
|
case typeClientKeyExchange:
|
|
m = new(clientKeyExchangeMsg)
|
|
case typeCertificateVerify:
|
|
m = new(certificateVerifyMsg)
|
|
case typeNextProtocol:
|
|
m = new(nextProtoMsg)
|
|
case typeFinished:
|
|
m = new(finishedMsg)
|
|
default:
|
|
c.sendAlert(alertUnexpectedMessage)
|
|
return nil, alertUnexpectedMessage
|
|
}
|
|
|
|
// The handshake message unmarshallers
|
|
// expect to be able to keep references to data,
|
|
// so pass in a fresh copy that won't be overwritten.
|
|
data = append([]byte(nil), data...)
|
|
|
|
if !m.unmarshal(data) {
|
|
c.sendAlert(alertUnexpectedMessage)
|
|
return nil, alertUnexpectedMessage
|
|
}
|
|
return m, nil
|
|
}
|
|
|
|
// Write writes data to the connection.
|
|
func (c *Conn) Write(b []byte) (n int, err error) {
|
|
if err = c.Handshake(); err != nil {
|
|
return
|
|
}
|
|
|
|
c.out.Lock()
|
|
defer c.out.Unlock()
|
|
|
|
if !c.handshakeComplete {
|
|
return 0, alertInternalError
|
|
}
|
|
if c.err != nil {
|
|
return 0, c.err
|
|
}
|
|
return c.writeRecord(recordTypeApplicationData, b)
|
|
}
|
|
|
|
// Read can be made to time out and return a net.Error with Timeout() == true
|
|
// after a fixed time limit; see SetTimeout and SetReadTimeout.
|
|
func (c *Conn) Read(b []byte) (n int, err error) {
|
|
if err = c.Handshake(); err != nil {
|
|
return
|
|
}
|
|
|
|
c.in.Lock()
|
|
defer c.in.Unlock()
|
|
|
|
for c.input == nil && c.err == nil {
|
|
if err := c.readRecord(recordTypeApplicationData); err != nil {
|
|
// Soft error, like EAGAIN
|
|
return 0, err
|
|
}
|
|
}
|
|
if c.err != nil {
|
|
return 0, c.err
|
|
}
|
|
n, err = c.input.Read(b)
|
|
if c.input.off >= len(c.input.data) {
|
|
c.in.freeBlock(c.input)
|
|
c.input = nil
|
|
}
|
|
return n, nil
|
|
}
|
|
|
|
// Close closes the connection.
|
|
func (c *Conn) Close() error {
|
|
var alertErr error
|
|
|
|
c.handshakeMutex.Lock()
|
|
defer c.handshakeMutex.Unlock()
|
|
if c.handshakeComplete {
|
|
alertErr = c.sendAlert(alertCloseNotify)
|
|
}
|
|
|
|
if err := c.conn.Close(); err != nil {
|
|
return err
|
|
}
|
|
return alertErr
|
|
}
|
|
|
|
// Handshake runs the client or server handshake
|
|
// protocol if it has not yet been run.
|
|
// Most uses of this package need not call Handshake
|
|
// explicitly: the first Read or Write will call it automatically.
|
|
func (c *Conn) Handshake() error {
|
|
c.handshakeMutex.Lock()
|
|
defer c.handshakeMutex.Unlock()
|
|
if err := c.error(); err != nil {
|
|
return err
|
|
}
|
|
if c.handshakeComplete {
|
|
return nil
|
|
}
|
|
if c.isClient {
|
|
return c.clientHandshake()
|
|
}
|
|
return c.serverHandshake()
|
|
}
|
|
|
|
// ConnectionState returns basic TLS details about the connection.
|
|
func (c *Conn) ConnectionState() ConnectionState {
|
|
c.handshakeMutex.Lock()
|
|
defer c.handshakeMutex.Unlock()
|
|
|
|
var state ConnectionState
|
|
state.HandshakeComplete = c.handshakeComplete
|
|
if c.handshakeComplete {
|
|
state.NegotiatedProtocol = c.clientProtocol
|
|
state.NegotiatedProtocolIsMutual = !c.clientProtocolFallback
|
|
state.CipherSuite = c.cipherSuite
|
|
state.PeerCertificates = c.peerCertificates
|
|
state.VerifiedChains = c.verifiedChains
|
|
state.ServerName = c.serverName
|
|
}
|
|
|
|
return state
|
|
}
|
|
|
|
// OCSPResponse returns the stapled OCSP response from the TLS server, if
|
|
// any. (Only valid for client connections.)
|
|
func (c *Conn) OCSPResponse() []byte {
|
|
c.handshakeMutex.Lock()
|
|
defer c.handshakeMutex.Unlock()
|
|
|
|
return c.ocspResponse
|
|
}
|
|
|
|
// VerifyHostname checks that the peer certificate chain is valid for
|
|
// connecting to host. If so, it returns nil; if not, it returns an error
|
|
// describing the problem.
|
|
func (c *Conn) VerifyHostname(host string) error {
|
|
c.handshakeMutex.Lock()
|
|
defer c.handshakeMutex.Unlock()
|
|
if !c.isClient {
|
|
return errors.New("VerifyHostname called on TLS server connection")
|
|
}
|
|
if !c.handshakeComplete {
|
|
return errors.New("TLS handshake has not yet been performed")
|
|
}
|
|
return c.peerCertificates[0].VerifyHostname(host)
|
|
}
|