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path: root/libgo/go/crypto/tls/handshake_server.go
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Diffstat (limited to 'libgo/go/crypto/tls/handshake_server.go')
-rw-r--r--libgo/go/crypto/tls/handshake_server.go285
1 files changed, 285 insertions, 0 deletions
diff --git a/libgo/go/crypto/tls/handshake_server.go b/libgo/go/crypto/tls/handshake_server.go
new file mode 100644
index 0000000000..955811ada3
--- /dev/null
+++ b/libgo/go/crypto/tls/handshake_server.go
@@ -0,0 +1,285 @@
+// Copyright 2009 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 tls
+
+import (
+ "crypto/rsa"
+ "crypto/subtle"
+ "crypto/x509"
+ "io"
+ "os"
+)
+
+func (c *Conn) serverHandshake() os.Error {
+ config := c.config
+ msg, err := c.readHandshake()
+ if err != nil {
+ return err
+ }
+ clientHello, ok := msg.(*clientHelloMsg)
+ if !ok {
+ return c.sendAlert(alertUnexpectedMessage)
+ }
+ vers, ok := mutualVersion(clientHello.vers)
+ if !ok {
+ return c.sendAlert(alertProtocolVersion)
+ }
+ c.vers = vers
+ c.haveVers = true
+
+ finishedHash := newFinishedHash()
+ finishedHash.Write(clientHello.marshal())
+
+ hello := new(serverHelloMsg)
+
+ supportedCurve := false
+Curves:
+ for _, curve := range clientHello.supportedCurves {
+ switch curve {
+ case curveP256, curveP384, curveP521:
+ supportedCurve = true
+ break Curves
+ }
+ }
+
+ supportedPointFormat := false
+ for _, pointFormat := range clientHello.supportedPoints {
+ if pointFormat == pointFormatUncompressed {
+ supportedPointFormat = true
+ break
+ }
+ }
+
+ ellipticOk := supportedCurve && supportedPointFormat
+
+ var suite *cipherSuite
+ var suiteId uint16
+ for _, id := range clientHello.cipherSuites {
+ for _, supported := range config.cipherSuites() {
+ if id == supported {
+ suite = cipherSuites[id]
+ // Don't select a ciphersuite which we can't
+ // support for this client.
+ if suite.elliptic && !ellipticOk {
+ continue
+ }
+ suiteId = id
+ break
+ }
+ }
+ }
+
+ foundCompression := false
+ // We only support null compression, so check that the client offered it.
+ for _, compression := range clientHello.compressionMethods {
+ if compression == compressionNone {
+ foundCompression = true
+ break
+ }
+ }
+
+ if suite == nil || !foundCompression {
+ return c.sendAlert(alertHandshakeFailure)
+ }
+
+ hello.vers = vers
+ hello.cipherSuite = suiteId
+ t := uint32(config.time())
+ hello.random = make([]byte, 32)
+ hello.random[0] = byte(t >> 24)
+ hello.random[1] = byte(t >> 16)
+ hello.random[2] = byte(t >> 8)
+ hello.random[3] = byte(t)
+ _, err = io.ReadFull(config.rand(), hello.random[4:])
+ if err != nil {
+ return c.sendAlert(alertInternalError)
+ }
+ hello.compressionMethod = compressionNone
+ if clientHello.nextProtoNeg {
+ hello.nextProtoNeg = true
+ hello.nextProtos = config.NextProtos
+ }
+
+ finishedHash.Write(hello.marshal())
+ c.writeRecord(recordTypeHandshake, hello.marshal())
+
+ if len(config.Certificates) == 0 {
+ return c.sendAlert(alertInternalError)
+ }
+
+ certMsg := new(certificateMsg)
+ certMsg.certificates = config.Certificates[0].Certificate
+ finishedHash.Write(certMsg.marshal())
+ c.writeRecord(recordTypeHandshake, certMsg.marshal())
+
+ keyAgreement := suite.ka()
+
+ skx, err := keyAgreement.generateServerKeyExchange(config, clientHello, hello)
+ if err != nil {
+ c.sendAlert(alertHandshakeFailure)
+ return err
+ }
+ if skx != nil {
+ finishedHash.Write(skx.marshal())
+ c.writeRecord(recordTypeHandshake, skx.marshal())
+ }
+
+ if config.AuthenticateClient {
+ // Request a client certificate
+ certReq := new(certificateRequestMsg)
+ certReq.certificateTypes = []byte{certTypeRSASign}
+ // An empty list of certificateAuthorities signals to
+ // the client that it may send any certificate in response
+ // to our request.
+
+ finishedHash.Write(certReq.marshal())
+ c.writeRecord(recordTypeHandshake, certReq.marshal())
+ }
+
+ helloDone := new(serverHelloDoneMsg)
+ finishedHash.Write(helloDone.marshal())
+ c.writeRecord(recordTypeHandshake, helloDone.marshal())
+
+ var pub *rsa.PublicKey
+ if config.AuthenticateClient {
+ // Get client certificate
+ msg, err = c.readHandshake()
+ if err != nil {
+ return err
+ }
+ certMsg, ok = msg.(*certificateMsg)
+ if !ok {
+ return c.sendAlert(alertUnexpectedMessage)
+ }
+ finishedHash.Write(certMsg.marshal())
+
+ certs := make([]*x509.Certificate, len(certMsg.certificates))
+ for i, asn1Data := range certMsg.certificates {
+ cert, err := x509.ParseCertificate(asn1Data)
+ if err != nil {
+ c.sendAlert(alertBadCertificate)
+ return os.ErrorString("could not parse client's certificate: " + err.String())
+ }
+ certs[i] = cert
+ }
+
+ // TODO(agl): do better validation of certs: max path length, name restrictions etc.
+ for i := 1; i < len(certs); i++ {
+ if err := certs[i-1].CheckSignatureFrom(certs[i]); err != nil {
+ c.sendAlert(alertBadCertificate)
+ return os.ErrorString("could not validate certificate signature: " + err.String())
+ }
+ }
+
+ if len(certs) > 0 {
+ key, ok := certs[0].PublicKey.(*rsa.PublicKey)
+ if !ok {
+ return c.sendAlert(alertUnsupportedCertificate)
+ }
+ pub = key
+ c.peerCertificates = certs
+ }
+ }
+
+ // Get client key exchange
+ msg, err = c.readHandshake()
+ if err != nil {
+ return err
+ }
+ ckx, ok := msg.(*clientKeyExchangeMsg)
+ if !ok {
+ return c.sendAlert(alertUnexpectedMessage)
+ }
+ finishedHash.Write(ckx.marshal())
+
+ // If we received a client cert in response to our certificate request message,
+ // the client will send us a certificateVerifyMsg immediately after the
+ // clientKeyExchangeMsg. This message is a MD5SHA1 digest of all preceeding
+ // handshake-layer messages that is signed using the private key corresponding
+ // to the client's certificate. This allows us to verify that the client is in
+ // posession of the private key of the certificate.
+ if len(c.peerCertificates) > 0 {
+ msg, err = c.readHandshake()
+ if err != nil {
+ return err
+ }
+ certVerify, ok := msg.(*certificateVerifyMsg)
+ if !ok {
+ return c.sendAlert(alertUnexpectedMessage)
+ }
+
+ digest := make([]byte, 36)
+ copy(digest[0:16], finishedHash.serverMD5.Sum())
+ copy(digest[16:36], finishedHash.serverSHA1.Sum())
+ err = rsa.VerifyPKCS1v15(pub, rsa.HashMD5SHA1, digest, certVerify.signature)
+ if err != nil {
+ c.sendAlert(alertBadCertificate)
+ return os.ErrorString("could not validate signature of connection nonces: " + err.String())
+ }
+
+ finishedHash.Write(certVerify.marshal())
+ }
+
+ preMasterSecret, err := keyAgreement.processClientKeyExchange(config, ckx)
+ if err != nil {
+ c.sendAlert(alertHandshakeFailure)
+ return err
+ }
+
+ masterSecret, clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
+ keysFromPreMasterSecret10(preMasterSecret, clientHello.random, hello.random, suite.macLen, suite.keyLen, suite.ivLen)
+
+ clientCipher := suite.cipher(clientKey, clientIV, true /* for reading */ )
+ clientHash := suite.mac(clientMAC)
+ c.in.prepareCipherSpec(clientCipher, clientHash)
+ c.readRecord(recordTypeChangeCipherSpec)
+ if err := c.error(); err != nil {
+ return err
+ }
+
+ if hello.nextProtoNeg {
+ msg, err = c.readHandshake()
+ if err != nil {
+ return err
+ }
+ nextProto, ok := msg.(*nextProtoMsg)
+ if !ok {
+ return c.sendAlert(alertUnexpectedMessage)
+ }
+ finishedHash.Write(nextProto.marshal())
+ c.clientProtocol = nextProto.proto
+ }
+
+ msg, err = c.readHandshake()
+ if err != nil {
+ return err
+ }
+ clientFinished, ok := msg.(*finishedMsg)
+ if !ok {
+ return c.sendAlert(alertUnexpectedMessage)
+ }
+
+ verify := finishedHash.clientSum(masterSecret)
+ if len(verify) != len(clientFinished.verifyData) ||
+ subtle.ConstantTimeCompare(verify, clientFinished.verifyData) != 1 {
+ return c.sendAlert(alertHandshakeFailure)
+ }
+
+ finishedHash.Write(clientFinished.marshal())
+
+ serverCipher := suite.cipher(serverKey, serverIV, false /* not for reading */ )
+ serverHash := suite.mac(serverMAC)
+ c.out.prepareCipherSpec(serverCipher, serverHash)
+ c.writeRecord(recordTypeChangeCipherSpec, []byte{1})
+
+ finished := new(finishedMsg)
+ finished.verifyData = finishedHash.serverSum(masterSecret)
+ c.writeRecord(recordTypeHandshake, finished.marshal())
+
+ c.handshakeComplete = true
+ c.cipherSuite = suiteId
+
+ return nil
+}