httpproxy

package module
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 Go to latest Published: Apr 17, 2018 License: BSD-3-Clause Imports: 25 Imported by: 0

README

Go HTTP proxy server library

GoDoc

Package httpproxy provides a customizable HTTP proxy; supports HTTP, HTTPS through CONNECT. And also provides HTTPS connection using "Man in the Middle" style attack.

It's easy to use. httpproxy.Proxy implements Handler interface of net/http package to offer http.ListenAndServe function.

Installing

go get -u github.com/go-httpproxy/httpproxy
# or
go get -u gopkg.in/httpproxy.v1

Usage

Library has two significant structs: Proxy and Context.

Proxy struct
// Proxy defines parameters for running an HTTP Proxy. It implements
// http.Handler interface for ListenAndServe function. If you need, you must
// set Proxy struct before handling requests.
type Proxy struct {
	// Session number of last proxy request.
	SessionNo int64

	// RoundTripper interface to obtain remote response.
	// By default, it uses &http.Transport{}.
	Rt http.RoundTripper

	// Certificate key pair.
	Ca tls.Certificate

	// User data to use free.
	UserData interface{}

	// Error callback.
	OnError func(ctx *Context, where string, err *Error, opErr error)

	// Accept callback. It greets proxy request like ServeHTTP function of
	// http.Handler.
	// If it returns true, stops processing proxy request.
	OnAccept func(ctx *Context, w http.ResponseWriter, r *http.Request) bool

	// Auth callback. If you need authentication, set this callback.
	// If it returns true, authentication succeeded.
	OnAuth func(ctx *Context, authType string, user string, pass string) bool

	// Connect callback. It sets connect action and new host.
	// If len(newhost) > 0, host changes.
	OnConnect func(ctx *Context, host string) (ConnectAction ConnectAction,
		newHost string)

	// Request callback. It greets remote request.
	// If it returns non-nil response, stops processing remote request.
	OnRequest func(ctx *Context, req *http.Request) (resp *http.Response)

	// Response callback. It greets remote response.
	// Remote response sends after this callback.
	OnResponse func(ctx *Context, req *http.Request, resp *http.Response)

	// If ConnectAction is ConnectMitm, it sets chunked to Transfer-Encoding.
	// By default, true.
	MitmChunked bool

	// HTTP Authentication type. If it's not specified (""), uses "Basic".
	// By default, "".
	AuthType string
}
Context struct
// Context keeps context of each proxy request.
type Context struct {
	// Pointer of Proxy struct handled this context.
	// It's using internally. Don't change in Context struct!
	Prx *Proxy

	// Session number of this context obtained from Proxy struct.
	SessionNo int64

	// Sub session number of processing remote connection.
	SubSessionNo int64

	// Original Proxy request.
	// It's using internally. Don't change in Context struct!
	Req *http.Request

	// Original Proxy request, if proxy request method is CONNECT.
	// It's using internally. Don't change in Context struct!
	ConnectReq *http.Request

	// Action of after the CONNECT, if proxy request method is CONNECT.
	// It's using internally. Don't change in Context struct!
	ConnectAction ConnectAction

	// Remote host, if proxy request method is CONNECT.
	// It's using internally. Don't change in Context struct!
	ConnectHost string

	// User data to use free.
	UserData interface{}
}

Examples

For more examples, examples/

examples/go-httpproxy-simple
package main

import (
	"log"
	"net/http"

	"github.com/go-httpproxy/httpproxy"
)

func OnError(ctx *httpproxy.Context, where string,
	err *httpproxy.Error, opErr error) {
	// Log errors.
	log.Printf("ERR: %s: %s [%s]", where, err, opErr)
}

func OnAccept(ctx *httpproxy.Context, w http.ResponseWriter,
	r *http.Request) bool {
	// Handle local request has path "/info"
	if r.Method == "GET" && !r.URL.IsAbs() && r.URL.Path == "/info" {
		w.Write([]byte("This is go-httpproxy."))
		return true
	}
	return false
}

func OnAuth(ctx *httpproxy.Context, authType string, user string, pass string) bool {
	// Auth test user.
	if user == "test" && pass == "1234" {
		return true
	}
	return false
}

func OnConnect(ctx *httpproxy.Context, host string) (
	ConnectAction httpproxy.ConnectAction, newHost string) {
	// Apply "Man in the Middle" to all ssl connections. Never change host.
	return httpproxy.ConnectMitm, host
}

func OnRequest(ctx *httpproxy.Context, req *http.Request) (
	resp *http.Response) {
	// Log proxying requests.
	log.Printf("INFO: Proxy: %s %s", req.Method, req.URL.String())
	return
}

func OnResponse(ctx *httpproxy.Context, req *http.Request,
	resp *http.Response) {
	// Add header "Via: go-httpproxy".
	resp.Header.Add("Via", "go-httpproxy")
}

func main() {
	// Create a new proxy with default certificate pair.
	prx, _ := httpproxy.NewProxy()

	// Set handlers.
	prx.OnError = OnError
	prx.OnAccept = OnAccept
	prx.OnAuth = OnAuth
	prx.OnConnect = OnConnect
	prx.OnRequest = OnRequest
	prx.OnResponse = OnResponse

	// Listen...
	http.ListenAndServe(":8080", prx)
}

Documentation

Overview

Package httpproxy provides a customizable HTTP proxy; supports HTTP, HTTPS through CONNECT. And also provides HTTPS connection using "Man in the Middle" style attack.

It's easy to use. `httpproxy.Proxy` implements `Handler` interface of `net/http` package to offer `http.ListenAndServe` function.

Index

Constants

View Source 
const (
	// ConnectNone specifies that proxy request is not CONNECT.
	// If it returned in OnConnect, proxy connection closes immediately.
	ConnectNone = ConnectAction(iota)

	// ConnectProxy specifies directly socket proxy after the CONNECT.
	ConnectProxy

	// ConnectMitm specifies proxy "Man in the Middle" style attack
	// after the CONNECT.
	ConnectMitm
)

Constants of ConnectAction type.

Variables

View Source 
var (
	ErrPanic                       = NewError("panic")
	ErrResponseWrite               = NewError("response write")
	ErrRequestRead                 = NewError("request read")
	ErrRemoteConnect               = NewError("remote connect")
	ErrNotSupportHijacking         = NewError("hijacking not supported")
	ErrTLSSignHost                 = NewError("TLS sign host")
	ErrTLSHandshake                = NewError("TLS handshake")
	ErrAbsURLAfterCONNECT          = NewError("absolute URL after CONNECT")
	ErrRoundTrip                   = NewError("round trip")
	ErrUnsupportedTransferEncoding = NewError("unsupported transfer encoding")
	ErrNotSupportHTTPVer           = NewError("http version not supported")
)

Library specific errors.

View Source 
var DefaultCaCert = []byte(`-----BEGIN CERTIFICATE-----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za71dL9OcWeTzx0mJKmsIZzzSfNKPgqn8TJzHa1u3DhO9L+GN9VNz5bCPjOmjM2z
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IIJR4bz/vIQ/8QFbTi5ddS69bmvJ6PhI2pSc/RxWQVMLjc+cmsUMHiKtoM9QAn7C
6/As+YLBQYZ0+sJUcFFcIayVzi8bwQ09yY8R0U5xXGvDYapVJUMZufy8UKOQxAP2
Y2wEJAEFxUPoMozTlkxwZdvhDq/JwdCuc94cXLQ8oCu8zVgajb8WfYPKgwviHyZ+
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oyC3UQzcjvD8/yYnO9BTJXNNBfNbTVxi6UqMUMDnJccuZOXO02DbW8uI/hECAwEA
AaNQME4wHQYDVR0OBBYEFIGx22SSLgTh1NCzKxg4uTUfahqiMB8GA1UdIwQYMBaA
FIGx22SSLgTh1NCzKxg4uTUfahqiMAwGA1UdEwQFMAMBAf8wDQYJKoZIhvcNAQEL
BQADggIBAIMxUgLHrc1e4JDsttJfU9BlWI3y2kX90ss1r84pUq+Cg9pneRl5iq6K
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8i5FKzo3HDXsSPTCLN7TctnMg31OsaIO75ryIPjmkUZe9xn9g0qvDa8kMrNwRCKX
N9Xk9uXUHhM/Mf+3gknAiEBfjFnWIfw87y63jI4c98XBhxbGzcoonxNNa0ql7yrx
knQ7ST2huX4HTvN//lzmgcNWzvPg/sdbr9JTFZyPKCcWGrLsG2uN2g1/P6Mi1T/M
ToXw/R9Lu0AK2h1o7FJjoJndokH7Ha0fShpCbfEYieTNvZbwkpzMYR8+IEFPkvKm
Dox1P6CqdLNyHBikLCxcQM7AQmuijdciXyYwHOVr/1r0jZqM0zI51t9Kyuw5kn0K
b2Ir0ERgrXx8eMQBrW6eseIAtqSHXDK+RKkU38xnYTBe6Jbg6r1F8zk/mzUye4IO
34LC38AY9if1kCwegkEFMmaTY8Z4YD3sxmezvEbxeWaHk4TfMGISmKQ3U41T2yEJ
Ii9Vb07WDMQXou0ZZs7rnjAKo+sfFElTFewtS1wif4ZYBUJN1ln9G8qKaxbAiElm
MgzNfZ7WlnaJf2rfHJbvK9VqJ9z6dLRYPjCHhakJBtzsMdxysEGJ
-----END CERTIFICATE-----`)

DefaultCaCert provides default CA certificate.

View Source 
var DefaultCaKey = []byte(`-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----`)

DefaultCaKey provides default CA key.

Functions

func InMemoryResponse 

func InMemoryResponse(code int, header http.Header, body []byte) *http.Response

InMemoryResponse creates new HTTP response given arguments.

func ServeInMemory 

func ServeInMemory(w http.ResponseWriter, code int, header http.Header, body []byte) error

ServeInMemory serves HTTP response given arguments to http.ResponseWriter.

func ServeResponse 

func ServeResponse(w http.ResponseWriter, resp *http.Response) error

ServeResponse serves HTTP response to http.ResponseWriter.

func SignHosts 

func SignHosts(ca tls.Certificate, hosts []string) (*tls.Certificate, error)

SignHosts generates TLS certificate given hosts, signed by CA certificate.

Types

type CaSigner 

type CaSigner struct {
	// Ca specifies CA certificate. You must set before using.
	Ca *tls.Certificate
	// contains filtered or unexported fields
}

CaSigner is a certificate signer by CA certificate. It supports caching.

func NewCaSigner 

func NewCaSigner() *CaSigner

NewCaSigner returns a new CaSigner without caching.

func NewCaSignerCache 

func NewCaSignerCache(max int) *CaSigner

NewCaSignerCache returns a new CaSigner with caching given max.

func (*CaSigner) SignHost 

func (c *CaSigner) SignHost(host string) (cert *tls.Certificate)

SignHost generates TLS certificate given single host, signed by CA certificate.

type ConnResponseWriter 

type ConnResponseWriter struct {
	Conn net.Conn
	// contains filtered or unexported fields
}

ConnResponseWriter implements http.ResponseWriter interface to use hijacked HTTP connection.

func NewConnResponseWriter 

func NewConnResponseWriter(conn net.Conn) *ConnResponseWriter

NewConnResponseWriter returns a new ConnResponseWriter.

func (*ConnResponseWriter) Close 

func (c *ConnResponseWriter) Close() error

Close closes network connection.

func (*ConnResponseWriter) Header 

func (c *ConnResponseWriter) Header() http.Header

Header returns the header map that will be sent by WriteHeader.

func (*ConnResponseWriter) Write 

func (c *ConnResponseWriter) Write(body []byte) (int, error)

Write writes the data to the connection as part of an HTTP reply.

func (*ConnResponseWriter) WriteHeader 

func (c *ConnResponseWriter) WriteHeader(statusCode int)

WriteHeader sends an HTTP response header with status code.

type ConnectAction 

type ConnectAction int

ConnectAction specifies action of after the CONNECT.

type Context 

type Context struct {
	// Pointer of Proxy struct handled this context.
	// It's using internally. Don't change in Context struct!
	Prx *Proxy

	// Session number of this context obtained from Proxy struct.
	SessionNo int64

	// Sub session number of processing remote connection.
	SubSessionNo int64

	// Original Proxy request.
	// It's using internally. Don't change in Context struct!
	Req *http.Request

	// Original Proxy request, if proxy request method is CONNECT.
	// It's using internally. Don't change in Context struct!
	ConnectReq *http.Request

	// Action of after the CONNECT, if proxy request method is CONNECT.
	// It's using internally. Don't change in Context struct!
	ConnectAction ConnectAction

	// Remote host, if proxy request method is CONNECT.
	// It's using internally. Don't change in Context struct!
	ConnectHost string

	// User data to use free.
	UserData interface{}
	// contains filtered or unexported fields
}

Context keeps context of each proxy request.

type Error 

type Error struct {
	ErrString string
}

Error struct is base of library specific errors.

func NewError 

func NewError(errString string) *Error

NewError returns a new Error.

func (*Error) Error 

func (e *Error) Error() string

Error implements error interface.

type Proxy 

type Proxy struct {
	// Session number of last proxy request.
	SessionNo int64

	// RoundTripper interface to obtain remote response.
	// By default, it uses &http.Transport{}.
	Rt http.RoundTripper

	// Certificate key pair.
	Ca tls.Certificate

	// User data to use free.
	UserData interface{}

	// Error callback.
	OnError func(ctx *Context, where string, err *Error, opErr error)

	// Accept callback. It greets proxy request like ServeHTTP function of
	// http.Handler.
	// If it returns true, stops processing proxy request.
	OnAccept func(ctx *Context, w http.ResponseWriter, r *http.Request) bool

	// Auth callback. If you need authentication, set this callback.
	// If it returns true, authentication succeeded.
	OnAuth func(ctx *Context, authType string, user string, pass string) bool

	// Connect callback. It sets connect action and new host.
	// If len(newhost) > 0, host changes.
	OnConnect func(ctx *Context, host string) (ConnectAction ConnectAction,
		newHost string)

	// Request callback. It greets remote request.
	// If it returns non-nil response, stops processing remote request.
	OnRequest func(ctx *Context, req *http.Request) (resp *http.Response)

	// Response callback. It greets remote response.
	// Remote response sends after this callback.
	OnResponse func(ctx *Context, req *http.Request, resp *http.Response)

	// If ConnectAction is ConnectMitm, it sets chunked to Transfer-Encoding.
	// By default, true.
	MitmChunked bool

	// HTTP Authentication type. If it's not specified (""), uses "Basic".
	// By default, "".
	AuthType string
	// contains filtered or unexported fields
}

Proxy defines parameters for running an HTTP Proxy. It implements http.Handler interface for ListenAndServe function. If you need, you must set Proxy struct before handling requests.

func NewProxy 

func NewProxy() (*Proxy, error)

NewProxy returns a new Proxy has default CA certificate and key.

func NewProxyCert 

func NewProxyCert(caCert, caKey []byte) (*Proxy, error)

NewProxyCert returns a new Proxy given CA certificate and key.

func (*Proxy) ServeHTTP 

func (prx *Proxy) ServeHTTP(w http.ResponseWriter, r *http.Request)

ServeHTTP implements http.Handler.

Source Files

View all Source files

Directories

Path Synopsis
examples
go-httpproxy-demo
go-httpproxy-demo is an example for HTTP and HTTPS web proxy.
 go-httpproxy-demo is an example for HTTP and HTTPS web proxy.
go-httpproxy-simple

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