package main

import (
  "fmt"
  "github.com/go-ldap/ldap"
  "os"
)

func usage(code int, err error) {
  if err != nil {
    os.Stderr.WriteString(fmt.Sprintf("error %s\n", err))
  }
  os.Stderr.WriteString(fmt.Sprintf("usage: %s [uri] [bind_dn] [bind_pw] [base_dn] [uid]\n", os.Args[0]))
  os.Exit(code)
}

func main() {
  if len(os.Args) != 6 {
    usage(1, nil)
  }

  var ldap_uri string      = os.Args[1]
  var ldap_bind_dn string  = os.Args[2]
  var ldap_bind_pw string  = os.Args[3]
  var ldap_base_dn string  = os.Args[4]
  var uid string           = os.Args[5]

  l, err := ldap.DialURL(ldap_uri)
  if err != nil {
    usage(2, err)
  }

  defer l.Close()

  err = l.Bind(ldap_bind_dn, ldap_bind_pw)
  if err != nil {
    usage(3, err)
  }

  search_request := ldap.NewSearchRequest(ldap_base_dn, ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false, fmt.Sprintf("(&(objectClass=posixAccount)(uid=%s))", uid), []string{"dn", "sshPublicKey"}, nil)
  sr, err := l.Search(search_request)
  if err != nil {
    usage(4, err)
  }

  for _, entry := range(sr.Entries) {
    fmt.Printf("%v", entry.GetAttributeValue("sshPublicKey"))
  }
}