glider/proxy/http/http.go
2022-03-14 13:06:26 +08:00

122 lines
2.4 KiB
Go

// https://developer.mozilla.org/en-US/docs/Web/HTTP/Messages
// NOTE: never keep-alive so the implementation can be much easier.
// Package http implements a http proxy.
package http
import (
"encoding/base64"
"io"
"net/textproto"
"net/url"
"strings"
"github.com/nadoo/glider/pkg/log"
"github.com/nadoo/glider/proxy"
)
// HTTP struct.
type HTTP struct {
dialer proxy.Dialer
proxy proxy.Proxy
addr string
user string
password string
pretend bool
}
func init() {
proxy.RegisterDialer("http", NewHTTPDialer)
proxy.RegisterServer("http", NewHTTPServer)
}
// NewHTTP returns a http proxy.
func NewHTTP(s string, d proxy.Dialer, p proxy.Proxy) (*HTTP, error) {
u, err := url.Parse(s)
if err != nil {
log.F("parse err: %s", err)
return nil, err
}
addr := u.Host
user := u.User.Username()
pass, _ := u.User.Password()
h := &HTTP{
dialer: d,
proxy: p,
addr: addr,
user: user,
password: pass,
pretend: false,
}
if u.Query().Get("pretend") == "true" {
h.pretend = true
}
return h, nil
}
// parseStartLine parses "GET /foo HTTP/1.1" OR "HTTP/1.1 200 OK" into its three parts.
func parseStartLine(line string) (r1, r2, r3 string, ok bool) {
s1 := strings.Index(line, " ")
s2 := strings.Index(line[s1+1:], " ")
if s1 < 0 || s2 < 0 {
return
}
s2 += s1 + 1
return line[:s1], line[s1+1 : s2], line[s2+1:], true
}
func cleanHeaders(header textproto.MIMEHeader) {
header.Del("Proxy-Connection")
header.Del("Connection")
header.Del("Keep-Alive")
header.Del("Proxy-Authenticate")
header.Del("Proxy-Authorization")
header.Del("TE")
header.Del("Trailers")
header.Del("Transfer-Encoding")
header.Del("Upgrade")
}
func writeStartLine(w io.Writer, s1, s2, s3 string) {
io.WriteString(w, s1+" "+s2+" "+s3+"\r\n")
}
func writeHeaders(w io.Writer, header textproto.MIMEHeader) {
for key, values := range header {
for _, v := range values {
io.WriteString(w, key+": "+v+"\r\n")
}
}
io.WriteString(w, "\r\n")
}
func extractUserPass(auth string) (username, password string, ok bool) {
if !strings.HasPrefix(auth, "Basic ") {
return
}
b, err := base64.StdEncoding.DecodeString(strings.TrimPrefix(auth, "Basic "))
if err != nil {
return
}
s := string(b)
idx := strings.IndexByte(s, ':')
if idx < 0 {
return
}
return s[:idx], s[idx+1:], true
}
func init() {
proxy.AddUsage("http", `
Http scheme:
http://[user:pass@]host:port
`)
}