119 lines
2.1 KiB
Go
119 lines
2.1 KiB
Go
package ssh
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import (
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"crypto/rand"
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"crypto/rsa"
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"crypto/x509"
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"encoding/binary"
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"encoding/pem"
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"fmt"
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"golang.org/x/crypto/ssh"
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)
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func signerFromBlock(block *pem.Block) (ssh.Signer, error) {
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var key interface{}
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var err error
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switch block.Type {
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case "RSA PRIVATE KEY":
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key, err = x509.ParsePKCS1PrivateKey(block.Bytes)
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case "EC PRIVATE KEY":
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key, err = x509.ParseECPrivateKey(block.Bytes)
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case "DSA PRIVATE KEY":
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key, err = ssh.ParseDSAPrivateKey(block.Bytes)
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default:
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return nil, fmt.Errorf("unsupported key type %q", block.Type)
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}
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if err != nil {
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return nil, err
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}
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signer, err := ssh.NewSignerFromKey(key)
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if err != nil {
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return nil, err
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}
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return signer, nil
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}
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func decodePemBlocks(pemData []byte) []*pem.Block {
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var blocks []*pem.Block
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var block *pem.Block
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for {
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block, pemData = pem.Decode(pemData)
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if block == nil {
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return blocks
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}
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blocks = append(blocks, block)
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}
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}
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func generateSigner() (ssh.Signer, error) {
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key, err := rsa.GenerateKey(rand.Reader, 768)
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if err != nil {
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return nil, err
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}
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return ssh.NewSignerFromKey(key)
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}
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func parsePtyRequest(s []byte) (width, height int, ok bool) {
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_, s, ok = parseString(s)
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if !ok {
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return
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}
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width32, s, ok := parseUint32(s)
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if !ok {
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return
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}
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height32, _, ok := parseUint32(s)
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width = int(width32)
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height = int(height32)
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if width < 1 {
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ok = false
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}
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if height < 1 {
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ok = false
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}
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return
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}
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func parseWinchRequest(s []byte) (width, height int, ok bool) {
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width32, _, ok := parseUint32(s)
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if !ok {
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return
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}
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height32, _, ok := parseUint32(s)
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if !ok {
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return
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}
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width = int(width32)
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height = int(height32)
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if width < 1 {
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ok = false
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}
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if height < 1 {
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ok = false
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}
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return
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}
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func parseString(in []byte) (out string, rest []byte, ok bool) {
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if len(in) < 4 {
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return
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}
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length := binary.BigEndian.Uint32(in)
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if uint32(len(in)) < 4+length {
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return
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}
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out = string(in[4 : 4+length])
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rest = in[4+length:]
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ok = true
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return
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}
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func parseUint32(in []byte) (uint32, []byte, bool) {
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if len(in) < 4 {
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return 0, nil, false
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}
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return binary.BigEndian.Uint32(in), in[4:], true
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}
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