matterbridge/vendor/github.com/Rhymen/go-whatsapp/session.go

390 lines
12 KiB
Go

package whatsapp
import (
"crypto/hmac"
"crypto/rand"
"crypto/sha256"
"encoding/base64"
"encoding/json"
"fmt"
"time"
"github.com/Rhymen/go-whatsapp/crypto/cbc"
"github.com/Rhymen/go-whatsapp/crypto/curve25519"
"github.com/Rhymen/go-whatsapp/crypto/hkdf"
)
/*
Session contains session individual information. To be able to resume the connection without scanning the qr code
every time you should save the Session returned by Login and use RestoreSession the next time you want to login.
Every successful created connection returns a new Session. The Session(ClientToken, ServerToken) is altered after
every re-login and should be saved every time.
*/
type Session struct {
ClientId string
ClientToken string
ServerToken string
EncKey []byte
MacKey []byte
Wid string
}
type Info struct {
Battery int
Platform string
Connected bool
Pushname string
Wid string
Lc string
Phone *PhoneInfo
Plugged bool
Tos int
Lg string
Is24h bool
}
type PhoneInfo struct {
Mcc string
Mnc string
OsVersion string
DeviceManufacturer string
DeviceModel string
OsBuildNumber string
WaVersion string
}
func newInfoFromReq(info map[string]interface{}) *Info {
phoneInfo := info["phone"].(map[string]interface{})
ret := &Info{
Battery: int(info["battery"].(float64)),
Platform: info["platform"].(string),
Connected: info["connected"].(bool),
Pushname: info["pushname"].(string),
Wid: info["wid"].(string),
Lc: info["lc"].(string),
Phone: &PhoneInfo{
phoneInfo["mcc"].(string),
phoneInfo["mnc"].(string),
phoneInfo["os_version"].(string),
phoneInfo["device_manufacturer"].(string),
phoneInfo["device_model"].(string),
phoneInfo["os_build_number"].(string),
phoneInfo["wa_version"].(string),
},
Plugged: info["plugged"].(bool),
Lg: info["lg"].(string),
Tos: int(info["tos"].(float64)),
}
if is24h, ok := info["is24h"]; ok {
ret.Is24h = is24h.(bool)
}
return ret
}
/*
SetClientName sets the long and short client names that are sent to WhatsApp when logging in and displayed in the
WhatsApp Web device list. As the values are only sent when logging in, changing them after logging in is not possible.
*/
func (wac *Conn) SetClientName(long, short string) error {
if wac.session != nil && (wac.session.EncKey != nil || wac.session.MacKey != nil) {
return fmt.Errorf("cannot change client name after logging in")
}
wac.longClientName, wac.shortClientName = long, short
return nil
}
/*
Login is the function that creates a new whatsapp session and logs you in. If you do not want to scan the qr code
every time, you should save the returned session and use RestoreSession the next time. Login takes a writable channel
as an parameter. This channel is used to push the data represented by the qr code back to the user. The received data
should be displayed as an qr code in a way you prefer. To print a qr code to console you can use:
github.com/Baozisoftware/qrcode-terminal-go Example login procedure:
wac, err := whatsapp.NewConn(5 * time.Second)
if err != nil {
panic(err)
}
qr := make(chan string)
go func() {
terminal := qrcodeTerminal.New()
terminal.Get(<-qr).Print()
}()
session, err := wac.Login(qr)
if err != nil {
fmt.Fprintf(os.Stderr, "error during login: %v\n", err)
}
fmt.Printf("login successful, session: %v\n", session)
*/
func (wac *Conn) Login(qrChan chan<- string) (Session, error) {
session := Session{}
if wac.session != nil && (wac.session.EncKey != nil || wac.session.MacKey != nil) {
return session, fmt.Errorf("already logged in")
}
clientId := make([]byte, 16)
_, err := rand.Read(clientId)
if err != nil {
return session, fmt.Errorf("error creating random ClientId: %v", err)
}
session.ClientId = base64.StdEncoding.EncodeToString(clientId)
//oldVersion=8691
login := []interface{}{"admin", "init", []int{0, 3, 225}, []string{wac.longClientName, wac.shortClientName}, session.ClientId, true}
loginChan, err := wac.write(login)
if err != nil {
return session, fmt.Errorf("error writing login: %v\n", err)
}
var r string
select {
case r = <-loginChan:
case <-time.After(wac.msgTimeout):
return session, fmt.Errorf("login connection timed out")
}
var resp map[string]interface{}
if err = json.Unmarshal([]byte(r), &resp); err != nil {
return session, fmt.Errorf("error decoding login resp: %v\n", err)
}
ref := resp["ref"].(string)
priv, pub, err := curve25519.GenerateKey()
if err != nil {
return session, fmt.Errorf("error generating keys: %v\n", err)
}
//listener for Login response
messageTag := "s1"
wac.listener[messageTag] = make(chan string, 1)
qrChan <- fmt.Sprintf("%v,%v,%v", ref, base64.StdEncoding.EncodeToString(pub[:]), session.ClientId)
var resp2 []interface{}
select {
case r1 := <-wac.listener[messageTag]:
if err := json.Unmarshal([]byte(r1), &resp2); err != nil {
return session, fmt.Errorf("error decoding qr code resp: %v", err)
}
case <-time.After(time.Duration(resp["ttl"].(float64)) * time.Millisecond):
return session, fmt.Errorf("qr code scan timed out")
}
info := resp2[1].(map[string]interface{})
wac.Info = newInfoFromReq(info)
session.ClientToken = info["clientToken"].(string)
session.ServerToken = info["serverToken"].(string)
session.Wid = info["wid"].(string)
s := info["secret"].(string)
decodedSecret, err := base64.StdEncoding.DecodeString(s)
if err != nil {
return session, fmt.Errorf("error decoding secret: %v", err)
}
var pubKey [32]byte
copy(pubKey[:], decodedSecret[:32])
sharedSecret := curve25519.GenerateSharedSecret(*priv, pubKey)
hash := sha256.New
nullKey := make([]byte, 32)
h := hmac.New(hash, nullKey)
h.Write(sharedSecret)
sharedSecretExtended, err := hkdf.Expand(h.Sum(nil), 80, "")
if err != nil {
return session, fmt.Errorf("hkdf error: %v", err)
}
//login validation
checkSecret := make([]byte, 112)
copy(checkSecret[:32], decodedSecret[:32])
copy(checkSecret[32:], decodedSecret[64:])
h2 := hmac.New(hash, sharedSecretExtended[32:64])
h2.Write(checkSecret)
if !hmac.Equal(h2.Sum(nil), decodedSecret[32:64]) {
return session, fmt.Errorf("abort login")
}
keysEncrypted := make([]byte, 96)
copy(keysEncrypted[:16], sharedSecretExtended[64:])
copy(keysEncrypted[16:], decodedSecret[64:])
keyDecrypted, err := cbc.Decrypt(sharedSecretExtended[:32], nil, keysEncrypted)
if err != nil {
return session, fmt.Errorf("error decryptAes: %v", err)
}
session.EncKey = keyDecrypted[:32]
session.MacKey = keyDecrypted[32:64]
wac.session = &session
return session, nil
}
/*
RestoreSession is the function that restores a given session. It will try to reestablish the connection to the
WhatsAppWeb servers with the provided session. If it succeeds it will return a new session. This new session has to be
saved because the Client and Server-Token will change after every login. Logging in with old tokens is possible, but not
suggested. If so, a challenge has to be resolved which is just another possible point of failure.
*/
func (wac *Conn) RestoreSession(session Session) (Session, error) {
if wac.session != nil && (wac.session.EncKey != nil || wac.session.MacKey != nil) {
return Session{}, fmt.Errorf("already logged in")
}
wac.session = &session
//listener for Conn or challenge; s1 is not allowed to drop
wac.listener["s1"] = make(chan string, 1)
//admin init
init := []interface{}{"admin", "init", []int{0, 3, 225}, []string{wac.longClientName, wac.shortClientName}, session.ClientId, true}
initChan, err := wac.write(init)
if err != nil {
wac.session = nil
return Session{}, fmt.Errorf("error writing admin init: %v\n", err)
}
//admin login with takeover
login := []interface{}{"admin", "login", session.ClientToken, session.ServerToken, session.ClientId, "takeover"}
loginChan, err := wac.write(login)
if err != nil {
wac.session = nil
return Session{}, fmt.Errorf("error writing admin login: %v\n", err)
}
select {
case r := <-initChan:
var resp map[string]interface{}
if err = json.Unmarshal([]byte(r), &resp); err != nil {
wac.session = nil
return Session{}, fmt.Errorf("error decoding login connResp: %v\n", err)
}
if int(resp["status"].(float64)) != 200 {
wac.session = nil
return Session{}, fmt.Errorf("init responded with %d", resp["status"])
}
case <-time.After(wac.msgTimeout):
wac.session = nil
return Session{}, fmt.Errorf("restore session init timed out")
}
//wait for s1
var connResp []interface{}
select {
case r1 := <-wac.listener["s1"]:
if err := json.Unmarshal([]byte(r1), &connResp); err != nil {
wac.session = nil
return Session{}, fmt.Errorf("error decoding s1 message: %v\n", err)
}
case <-time.After(wac.msgTimeout):
wac.session = nil
return Session{}, fmt.Errorf("restore session connection timed out")
}
//check if challenge is present
if len(connResp) == 2 && connResp[0] == "Cmd" && connResp[1].(map[string]interface{})["type"] == "challenge" {
wac.listener["s2"] = make(chan string, 1)
if err := wac.resolveChallenge(connResp[1].(map[string]interface{})["challenge"].(string)); err != nil {
wac.session = nil
return Session{}, fmt.Errorf("error resolving challenge: %v\n", err)
}
select {
case r := <-wac.listener["s2"]:
if err := json.Unmarshal([]byte(r), &connResp); err != nil {
wac.session = nil
return Session{}, fmt.Errorf("error decoding s2 message: %v\n", err)
}
case <-time.After(wac.msgTimeout):
wac.session = nil
return Session{}, fmt.Errorf("restore session challenge timed out")
}
}
//check for login 200 --> login success
select {
case r := <-loginChan:
var resp map[string]interface{}
if err = json.Unmarshal([]byte(r), &resp); err != nil {
wac.session = nil
return Session{}, fmt.Errorf("error decoding login connResp: %v\n", err)
}
if int(resp["status"].(float64)) != 200 {
wac.session = nil
return Session{}, fmt.Errorf("admin login responded with %d", resp["status"])
}
case <-time.After(wac.msgTimeout):
wac.session = nil
return Session{}, fmt.Errorf("restore session login timed out")
}
info := connResp[1].(map[string]interface{})
wac.Info = newInfoFromReq(info)
//set new tokens
session.ClientToken = info["clientToken"].(string)
session.ServerToken = info["serverToken"].(string)
session.Wid = info["wid"].(string)
return *wac.session, nil
}
func (wac *Conn) resolveChallenge(challenge string) error {
decoded, err := base64.StdEncoding.DecodeString(challenge)
if err != nil {
return err
}
h2 := hmac.New(sha256.New, wac.session.MacKey)
h2.Write([]byte(decoded))
ch := []interface{}{"admin", "challenge", base64.StdEncoding.EncodeToString(h2.Sum(nil)), wac.session.ServerToken, wac.session.ClientId}
challengeChan, err := wac.write(ch)
if err != nil {
return fmt.Errorf("error writing challenge: %v\n", err)
}
select {
case r := <-challengeChan:
var resp map[string]interface{}
if err := json.Unmarshal([]byte(r), &resp); err != nil {
return fmt.Errorf("error decoding login resp: %v\n", err)
}
if int(resp["status"].(float64)) != 200 {
return fmt.Errorf("challenge responded with %d\n", resp["status"])
}
case <-time.After(wac.msgTimeout):
return fmt.Errorf("connection timed out")
}
return nil
}
/*
Logout is the function to logout from a WhatsApp session. Logging out means invalidating the current session.
The session can not be resumed and will disappear on your phone in the WhatsAppWeb client list.
*/
func (wac *Conn) Logout() error {
login := []interface{}{"admin", "Conn", "disconnect"}
_, err := wac.write(login)
if err != nil {
return fmt.Errorf("error writing logout: %v\n", err)
}
return nil
}