From 8c12c6939aab9106db14ec2d11d983bc5b29fb2c Mon Sep 17 00:00:00 2001 From: Niall Sheridan Date: Sun, 7 Jul 2019 21:33:44 +0100 Subject: Switch to modules --- vendor/golang.org/x/crypto/ssh/transport.go | 353 ---------------------------- 1 file changed, 353 deletions(-) delete mode 100644 vendor/golang.org/x/crypto/ssh/transport.go (limited to 'vendor/golang.org/x/crypto/ssh/transport.go') diff --git a/vendor/golang.org/x/crypto/ssh/transport.go b/vendor/golang.org/x/crypto/ssh/transport.go deleted file mode 100644 index f6fae1d..0000000 --- a/vendor/golang.org/x/crypto/ssh/transport.go +++ /dev/null @@ -1,353 +0,0 @@ -// 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 ( - "bufio" - "bytes" - "errors" - "io" - "log" -) - -// debugTransport if set, will print packet types as they go over the -// wire. No message decoding is done, to minimize the impact on timing. -const debugTransport = false - -const ( - gcmCipherID = "aes128-gcm@openssh.com" - aes128cbcID = "aes128-cbc" - tripledescbcID = "3des-cbc" -) - -// packetConn represents a transport that implements packet based -// operations. -type packetConn interface { - // Encrypt and send a packet of data to the remote peer. - writePacket(packet []byte) error - - // Read a packet from the connection. The read is blocking, - // i.e. if error is nil, then the returned byte slice is - // always non-empty. - readPacket() ([]byte, error) - - // Close closes the write-side of the connection. - Close() error -} - -// transport is the keyingTransport that implements the SSH packet -// protocol. -type transport struct { - reader connectionState - writer connectionState - - bufReader *bufio.Reader - bufWriter *bufio.Writer - rand io.Reader - isClient bool - io.Closer -} - -// packetCipher represents a combination of SSH encryption/MAC -// protocol. A single instance should be used for one direction only. -type packetCipher interface { - // writePacket encrypts the packet and writes it to w. The - // contents of the packet are generally scrambled. - writePacket(seqnum uint32, w io.Writer, rand io.Reader, packet []byte) error - - // readPacket reads and decrypts a packet of data. The - // returned packet may be overwritten by future calls of - // readPacket. - readPacket(seqnum uint32, r io.Reader) ([]byte, error) -} - -// connectionState represents one side (read or write) of the -// connection. This is necessary because each direction has its own -// keys, and can even have its own algorithms -type connectionState struct { - packetCipher - seqNum uint32 - dir direction - pendingKeyChange chan packetCipher -} - -// prepareKeyChange sets up key material for a keychange. The key changes in -// both directions are triggered by reading and writing a msgNewKey packet -// respectively. -func (t *transport) prepareKeyChange(algs *algorithms, kexResult *kexResult) error { - ciph, err := newPacketCipher(t.reader.dir, algs.r, kexResult) - if err != nil { - return err - } - t.reader.pendingKeyChange <- ciph - - ciph, err = newPacketCipher(t.writer.dir, algs.w, kexResult) - if err != nil { - return err - } - t.writer.pendingKeyChange <- ciph - - return nil -} - -func (t *transport) printPacket(p []byte, write bool) { - if len(p) == 0 { - return - } - who := "server" - if t.isClient { - who = "client" - } - what := "read" - if write { - what = "write" - } - - log.Println(what, who, p[0]) -} - -// Read and decrypt next packet. -func (t *transport) readPacket() (p []byte, err error) { - for { - p, err = t.reader.readPacket(t.bufReader) - if err != nil { - break - } - if len(p) == 0 || (p[0] != msgIgnore && p[0] != msgDebug) { - break - } - } - if debugTransport { - t.printPacket(p, false) - } - - return p, err -} - -func (s *connectionState) readPacket(r *bufio.Reader) ([]byte, error) { - packet, err := s.packetCipher.readPacket(s.seqNum, r) - s.seqNum++ - if err == nil && len(packet) == 0 { - err = errors.New("ssh: zero length packet") - } - - if len(packet) > 0 { - switch packet[0] { - case msgNewKeys: - select { - case cipher := <-s.pendingKeyChange: - s.packetCipher = cipher - default: - return nil, errors.New("ssh: got bogus newkeys message") - } - - case msgDisconnect: - // Transform a disconnect message into an - // error. Since this is lowest level at which - // we interpret message types, doing it here - // ensures that we don't have to handle it - // elsewhere. - var msg disconnectMsg - if err := Unmarshal(packet, &msg); err != nil { - return nil, err - } - return nil, &msg - } - } - - // The packet may point to an internal buffer, so copy the - // packet out here. - fresh := make([]byte, len(packet)) - copy(fresh, packet) - - return fresh, err -} - -func (t *transport) writePacket(packet []byte) error { - if debugTransport { - t.printPacket(packet, true) - } - return t.writer.writePacket(t.bufWriter, t.rand, packet) -} - -func (s *connectionState) writePacket(w *bufio.Writer, rand io.Reader, packet []byte) error { - changeKeys := len(packet) > 0 && packet[0] == msgNewKeys - - err := s.packetCipher.writePacket(s.seqNum, w, rand, packet) - if err != nil { - return err - } - if err = w.Flush(); err != nil { - return err - } - s.seqNum++ - if changeKeys { - select { - case cipher := <-s.pendingKeyChange: - s.packetCipher = cipher - default: - panic("ssh: no key material for msgNewKeys") - } - } - return err -} - -func newTransport(rwc io.ReadWriteCloser, rand io.Reader, isClient bool) *transport { - t := &transport{ - bufReader: bufio.NewReader(rwc), - bufWriter: bufio.NewWriter(rwc), - rand: rand, - reader: connectionState{ - packetCipher: &streamPacketCipher{cipher: noneCipher{}}, - pendingKeyChange: make(chan packetCipher, 1), - }, - writer: connectionState{ - packetCipher: &streamPacketCipher{cipher: noneCipher{}}, - pendingKeyChange: make(chan packetCipher, 1), - }, - Closer: rwc, - } - t.isClient = isClient - - if isClient { - t.reader.dir = serverKeys - t.writer.dir = clientKeys - } else { - t.reader.dir = clientKeys - t.writer.dir = serverKeys - } - - return t -} - -type direction struct { - ivTag []byte - keyTag []byte - macKeyTag []byte -} - -var ( - serverKeys = direction{[]byte{'B'}, []byte{'D'}, []byte{'F'}} - clientKeys = direction{[]byte{'A'}, []byte{'C'}, []byte{'E'}} -) - -// setupKeys sets the cipher and MAC keys from kex.K, kex.H and sessionId, as -// described in RFC 4253, section 6.4. direction should either be serverKeys -// (to setup server->client keys) or clientKeys (for client->server keys). -func newPacketCipher(d direction, algs directionAlgorithms, kex *kexResult) (packetCipher, error) { - cipherMode := cipherModes[algs.Cipher] - macMode := macModes[algs.MAC] - - iv := make([]byte, cipherMode.ivSize) - key := make([]byte, cipherMode.keySize) - macKey := make([]byte, macMode.keySize) - - generateKeyMaterial(iv, d.ivTag, kex) - generateKeyMaterial(key, d.keyTag, kex) - generateKeyMaterial(macKey, d.macKeyTag, kex) - - return cipherModes[algs.Cipher].create(key, iv, macKey, algs) -} - -// generateKeyMaterial fills out with key material generated from tag, K, H -// and sessionId, as specified in RFC 4253, section 7.2. -func generateKeyMaterial(out, tag []byte, r *kexResult) { - var digestsSoFar []byte - - h := r.Hash.New() - for len(out) > 0 { - h.Reset() - h.Write(r.K) - h.Write(r.H) - - if len(digestsSoFar) == 0 { - h.Write(tag) - h.Write(r.SessionID) - } else { - h.Write(digestsSoFar) - } - - digest := h.Sum(nil) - n := copy(out, digest) - out = out[n:] - if len(out) > 0 { - digestsSoFar = append(digestsSoFar, digest...) - } - } -} - -const packageVersion = "SSH-2.0-Go" - -// Sends and receives a version line. The versionLine string should -// be US ASCII, start with "SSH-2.0-", and should not include a -// newline. exchangeVersions returns the other side's version line. -func exchangeVersions(rw io.ReadWriter, versionLine []byte) (them []byte, err error) { - // Contrary to the RFC, we do not ignore lines that don't - // start with "SSH-2.0-" to make the library usable with - // nonconforming servers. - for _, c := range versionLine { - // The spec disallows non US-ASCII chars, and - // specifically forbids null chars. - if c < 32 { - return nil, errors.New("ssh: junk character in version line") - } - } - if _, err = rw.Write(append(versionLine, '\r', '\n')); err != nil { - return - } - - them, err = readVersion(rw) - return them, err -} - -// maxVersionStringBytes is the maximum number of bytes that we'll -// accept as a version string. RFC 4253 section 4.2 limits this at 255 -// chars -const maxVersionStringBytes = 255 - -// Read version string as specified by RFC 4253, section 4.2. -func readVersion(r io.Reader) ([]byte, error) { - versionString := make([]byte, 0, 64) - var ok bool - var buf [1]byte - - for length := 0; length < maxVersionStringBytes; length++ { - _, err := io.ReadFull(r, buf[:]) - if err != nil { - return nil, err - } - // The RFC says that the version should be terminated with \r\n - // but several SSH servers actually only send a \n. - if buf[0] == '\n' { - if !bytes.HasPrefix(versionString, []byte("SSH-")) { - // RFC 4253 says we need to ignore all version string lines - // except the one containing the SSH version (provided that - // all the lines do not exceed 255 bytes in total). - versionString = versionString[:0] - continue - } - ok = true - break - } - - // non ASCII chars are disallowed, but we are lenient, - // since Go doesn't use null-terminated strings. - - // The RFC allows a comment after a space, however, - // all of it (version and comments) goes into the - // session hash. - versionString = append(versionString, buf[0]) - } - - if !ok { - return nil, errors.New("ssh: overflow reading version string") - } - - // There might be a '\r' on the end which we should remove. - if len(versionString) > 0 && versionString[len(versionString)-1] == '\r' { - versionString = versionString[:len(versionString)-1] - } - return versionString, nil -} -- cgit v1.2.3