/
net.go
72 lines (65 loc) · 1.34 KB
/
net.go
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package socks
import (
"bytes"
"errors"
"fmt"
"net"
"strconv"
"time"
)
type requestBuilder struct {
bytes.Buffer
}
func (b *requestBuilder) add(data ...byte) {
_, _ = b.Write(data)
}
func (c *config) sendReceive(conn net.Conn, req []byte) (resp []byte, err error) {
if c.Timeout > 0 {
if err := conn.SetWriteDeadline(time.Now().Add(c.Timeout)); err != nil {
return nil, err
}
}
_, err = conn.Write(req)
if err != nil {
return
}
resp, err = c.readAll(conn)
return
}
func (c *config) readAll(conn net.Conn) (resp []byte, err error) {
resp = make([]byte, 1024)
if c.Timeout > 0 {
if err := conn.SetReadDeadline(time.Now().Add(c.Timeout)); err != nil {
return nil, err
}
}
n, err := conn.Read(resp)
resp = resp[:n]
return
}
func lookupIP(host string) (net.IP, error) {
ips, err := net.LookupIP(host)
if err != nil {
return nil, err
}
if len(ips) == 0 {
return nil, fmt.Errorf("cannot resolve host: %s", host)
}
ip := ips[0].To4()
if len(ip) != net.IPv4len {
return nil, errors.New("ipv6 is not supported by SOCKS4")
}
return ip, nil
}
func splitHostPort(addr string) (host string, port uint16, err error) {
host, portStr, err := net.SplitHostPort(addr)
if err != nil {
return "", 0, err
}
portInt, err := strconv.ParseUint(portStr, 10, 16)
if err != nil {
return "", 0, err
}
port = uint16(portInt)
return
}