gobuster/gobustervhost/gobustervhost.go

package gobustervhost

import (
	"bufio"
	"bytes"
	"context"
	"fmt"
	"net/url"
	"strings"
	"text/tabwriter"

	"github.com/OJ/gobuster/v3/libgobuster"
	"github.com/google/uuid"
)

// GobusterVhost is the main type to implement the interface
type GobusterVhost struct {
	options    *OptionsVhost
	globalopts *libgobuster.Options
	http       *libgobuster.HTTPClient
	domain     string
	baseline1  []byte
	baseline2  []byte
}

// NewGobusterVhost creates a new initialized GobusterDir
func NewGobusterVhost(cont context.Context, globalopts *libgobuster.Options, opts *OptionsVhost) (*GobusterVhost, error) {
	if globalopts == nil {
		return nil, fmt.Errorf("please provide valid global options")
	}

	if opts == nil {
		return nil, fmt.Errorf("please provide valid plugin options")
	}

	g := GobusterVhost{
		options:    opts,
		globalopts: globalopts,
	}

	basicOptions := libgobuster.BasicHTTPOptions{
		Proxy:     opts.Proxy,
		Timeout:   opts.Timeout,
		UserAgent: opts.UserAgent,
	}

	httpOpts := libgobuster.HTTPOptions{
		BasicHTTPOptions: basicOptions,
		FollowRedirect:   opts.FollowRedirect,
		NoTLSValidation:  opts.NoTLSValidation,
		Username:         opts.Username,
		Password:         opts.Password,
		Headers:          opts.Headers,
		Cookies:          opts.Cookies,
		Method:           opts.Method,
	}

	h, err := libgobuster.NewHTTPClient(cont, &httpOpts)
	if err != nil {
		return nil, err
	}
	g.http = h
	return &g, nil
}

// Name should return the name of the plugin
func (v *GobusterVhost) Name() string {
	return "VHOST enumeration"
}

// RequestsPerRun returns the number of requests this plugin makes per single wordlist item
func (v *GobusterVhost) RequestsPerRun() int {
	return 1
}

// PreRun is the pre run implementation of gobusterdir
func (v *GobusterVhost) PreRun() error {
	// add trailing slash
	if !strings.HasSuffix(v.options.URL, "/") {
		v.options.URL = fmt.Sprintf("%s/", v.options.URL)
	}

	urlParsed, err := url.Parse(v.options.URL)
	if err != nil {
		return fmt.Errorf("invalid url %s: %w", v.options.URL, err)
	}
	v.domain = urlParsed.Host

	// request default vhost for baseline1
	_, _, _, tmp, err := v.http.Request(v.options.URL, libgobuster.RequestOptions{ReturnBody: true})
	if err != nil {
		return fmt.Errorf("unable to connect to %s: %w", v.options.URL, err)
	}
	v.baseline1 = tmp

	// request non existent vhost for baseline2
	subdomain := fmt.Sprintf("%s.%s", uuid.New(), v.domain)
	_, _, _, tmp, err = v.http.Request(v.options.URL, libgobuster.RequestOptions{Host: subdomain, ReturnBody: true})
	if err != nil {
		return fmt.Errorf("unable to connect to %s: %w", v.options.URL, err)
	}
	v.baseline2 = tmp
	return nil
}

// Run is the process implementation of gobusterdir
func (v *GobusterVhost) Run(word string, resChannel chan<- libgobuster.Result) error {
	var subdomain string
	if v.options.AppendDomain {
		subdomain = fmt.Sprintf("%s.%s", word, v.domain)
	} else {
		// wordlist needs to include full domains
		subdomain = word
	}
	status, size, header, body, err := v.http.Request(v.options.URL, libgobuster.RequestOptions{Host: subdomain, ReturnBody: true})
	if err != nil {
		return err
	}

	// subdomain must not match default vhost and non existent vhost
	// or verbose mode is enabled
	found := !bytes.Equal(body, v.baseline1) && !bytes.Equal(body, v.baseline2)
	if found || v.globalopts.Verbose {
		resultStatus := false
		if found {
			resultStatus = true
		}
		resChannel <- Result{
			Found:      resultStatus,
			Vhost:      subdomain,
			StatusCode: *status,
			Size:       size,
			Header:     header,
		}
	}
	return nil
}

// GetConfigString returns the string representation of the current config
func (v *GobusterVhost) GetConfigString() (string, error) {
	var buffer bytes.Buffer
	bw := bufio.NewWriter(&buffer)
	tw := tabwriter.NewWriter(bw, 0, 5, 3, ' ', 0)
	o := v.options
	if _, err := fmt.Fprintf(tw, "[+] Url:\t%s\n", o.URL); err != nil {
		return "", err
	}

	if _, err := fmt.Fprintf(tw, "[+] Method:\t%s\n", o.Method); err != nil {
		return "", err
	}

	if _, err := fmt.Fprintf(tw, "[+] Threads:\t%d\n", v.globalopts.Threads); err != nil {
		return "", err
	}

	if v.globalopts.Delay > 0 {
		if _, err := fmt.Fprintf(tw, "[+] Delay:\t%s\n", v.globalopts.Delay); err != nil {
			return "", err
		}
	}

	wordlist := "stdin (pipe)"
	if v.globalopts.Wordlist != "-" {
		wordlist = v.globalopts.Wordlist
	}
	if _, err := fmt.Fprintf(tw, "[+] Wordlist:\t%s\n", wordlist); err != nil {
		return "", err
	}

	if v.globalopts.PatternFile != "" {
		if _, err := fmt.Fprintf(tw, "[+] Patterns:\t%s (%d entries)\n", v.globalopts.PatternFile, len(v.globalopts.Patterns)); err != nil {
			return "", err
		}
	}

	if o.Proxy != "" {
		if _, err := fmt.Fprintf(tw, "[+] Proxy:\t%s\n", o.Proxy); err != nil {
			return "", err
		}
	}

	if o.Cookies != "" {
		if _, err := fmt.Fprintf(tw, "[+] Cookies:\t%s\n", o.Cookies); err != nil {
			return "", err
		}
	}

	if o.UserAgent != "" {
		if _, err := fmt.Fprintf(tw, "[+] User Agent:\t%s\n", o.UserAgent); err != nil {
			return "", err
		}
	}

	if o.Username != "" {
		if _, err := fmt.Fprintf(tw, "[+] Auth User:\t%s\n", o.Username); err != nil {
			return "", err
		}
	}

	if v.globalopts.Verbose {
		if _, err := fmt.Fprintf(tw, "[+] Verbose:\ttrue\n"); err != nil {
			return "", err
		}
	}

	if _, err := fmt.Fprintf(tw, "[+] Timeout:\t%s\n", o.Timeout.String()); err != nil {
		return "", err
	}

	if err := tw.Flush(); err != nil {
		return "", fmt.Errorf("error on tostring: %w", err)
	}

	if err := bw.Flush(); err != nil {
		return "", fmt.Errorf("error on tostring: %w", err)
	}

	return strings.TrimSpace(buffer.String()), nil
}