diff options
author | Austin Clements <austin@google.com> | 2014-10-22 13:25:37 -0400 |
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committer | Austin Clements <austin@google.com> | 2014-10-22 13:25:37 -0400 |
commit | 800a826ae560191d4dbb6c529eea15cf4349a06f (patch) | |
tree | c4206bb02365c3b9c66e2946031b86f0ee527faf /src/crypto/tls/ticket.go | |
parent | 2c586384223e980fd3303625ea6b02ed5d9fb9c0 (diff) | |
parent | 1678ee65674b332e900a703de296eb66fbadcf45 (diff) | |
download | go-800a826ae560191d4dbb6c529eea15cf4349a06f.tar.gz |
build: merge the great pkg/ rename into dev.power64
This also removes pkg/runtime/traceback_lr.c, which was ported
to Go in an earlier commit and then moved to
runtime/traceback.go.
Reviewer: rsc@golang.org
rsc: LGTM
Diffstat (limited to 'src/crypto/tls/ticket.go')
-rw-r--r-- | src/crypto/tls/ticket.go | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/src/crypto/tls/ticket.go b/src/crypto/tls/ticket.go new file mode 100644 index 000000000..4cfc5a53f --- /dev/null +++ b/src/crypto/tls/ticket.go @@ -0,0 +1,182 @@ +// Copyright 2012 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package tls + +import ( + "bytes" + "crypto/aes" + "crypto/cipher" + "crypto/hmac" + "crypto/sha256" + "crypto/subtle" + "errors" + "io" +) + +// sessionState contains the information that is serialized into a session +// ticket in order to later resume a connection. +type sessionState struct { + vers uint16 + cipherSuite uint16 + masterSecret []byte + certificates [][]byte +} + +func (s *sessionState) equal(i interface{}) bool { + s1, ok := i.(*sessionState) + if !ok { + return false + } + + if s.vers != s1.vers || + s.cipherSuite != s1.cipherSuite || + !bytes.Equal(s.masterSecret, s1.masterSecret) { + return false + } + + if len(s.certificates) != len(s1.certificates) { + return false + } + + for i := range s.certificates { + if !bytes.Equal(s.certificates[i], s1.certificates[i]) { + return false + } + } + + return true +} + +func (s *sessionState) marshal() []byte { + length := 2 + 2 + 2 + len(s.masterSecret) + 2 + for _, cert := range s.certificates { + length += 4 + len(cert) + } + + ret := make([]byte, length) + x := ret + x[0] = byte(s.vers >> 8) + x[1] = byte(s.vers) + x[2] = byte(s.cipherSuite >> 8) + x[3] = byte(s.cipherSuite) + x[4] = byte(len(s.masterSecret) >> 8) + x[5] = byte(len(s.masterSecret)) + x = x[6:] + copy(x, s.masterSecret) + x = x[len(s.masterSecret):] + + x[0] = byte(len(s.certificates) >> 8) + x[1] = byte(len(s.certificates)) + x = x[2:] + + for _, cert := range s.certificates { + x[0] = byte(len(cert) >> 24) + x[1] = byte(len(cert) >> 16) + x[2] = byte(len(cert) >> 8) + x[3] = byte(len(cert)) + copy(x[4:], cert) + x = x[4+len(cert):] + } + + return ret +} + +func (s *sessionState) unmarshal(data []byte) bool { + if len(data) < 8 { + return false + } + + s.vers = uint16(data[0])<<8 | uint16(data[1]) + s.cipherSuite = uint16(data[2])<<8 | uint16(data[3]) + masterSecretLen := int(data[4])<<8 | int(data[5]) + data = data[6:] + if len(data) < masterSecretLen { + return false + } + + s.masterSecret = data[:masterSecretLen] + data = data[masterSecretLen:] + + if len(data) < 2 { + return false + } + + numCerts := int(data[0])<<8 | int(data[1]) + data = data[2:] + + s.certificates = make([][]byte, numCerts) + for i := range s.certificates { + if len(data) < 4 { + return false + } + certLen := int(data[0])<<24 | int(data[1])<<16 | int(data[2])<<8 | int(data[3]) + data = data[4:] + if certLen < 0 { + return false + } + if len(data) < certLen { + return false + } + s.certificates[i] = data[:certLen] + data = data[certLen:] + } + + if len(data) > 0 { + return false + } + + return true +} + +func (c *Conn) encryptTicket(state *sessionState) ([]byte, error) { + serialized := state.marshal() + encrypted := make([]byte, aes.BlockSize+len(serialized)+sha256.Size) + iv := encrypted[:aes.BlockSize] + macBytes := encrypted[len(encrypted)-sha256.Size:] + + if _, err := io.ReadFull(c.config.rand(), iv); err != nil { + return nil, err + } + block, err := aes.NewCipher(c.config.SessionTicketKey[:16]) + if err != nil { + return nil, errors.New("tls: failed to create cipher while encrypting ticket: " + err.Error()) + } + cipher.NewCTR(block, iv).XORKeyStream(encrypted[aes.BlockSize:], serialized) + + mac := hmac.New(sha256.New, c.config.SessionTicketKey[16:32]) + mac.Write(encrypted[:len(encrypted)-sha256.Size]) + mac.Sum(macBytes[:0]) + + return encrypted, nil +} + +func (c *Conn) decryptTicket(encrypted []byte) (*sessionState, bool) { + if len(encrypted) < aes.BlockSize+sha256.Size { + return nil, false + } + + iv := encrypted[:aes.BlockSize] + macBytes := encrypted[len(encrypted)-sha256.Size:] + + mac := hmac.New(sha256.New, c.config.SessionTicketKey[16:32]) + mac.Write(encrypted[:len(encrypted)-sha256.Size]) + expected := mac.Sum(nil) + + if subtle.ConstantTimeCompare(macBytes, expected) != 1 { + return nil, false + } + + block, err := aes.NewCipher(c.config.SessionTicketKey[:16]) + if err != nil { + return nil, false + } + ciphertext := encrypted[aes.BlockSize : len(encrypted)-sha256.Size] + plaintext := ciphertext + cipher.NewCTR(block, iv).XORKeyStream(plaintext, ciphertext) + + state := new(sessionState) + ok := state.unmarshal(plaintext) + return state, ok +} |