Rsa Encryption, probably bugged

This commit is contained in:
Pablu23
2023-12-08 20:39:52 +01:00
parent 6dfdd7f459
commit ca9320f5ee
9 changed files with 398 additions and 172 deletions

3
.gitignore vendored
View File

@@ -1,4 +1,5 @@
bin/
testFiles/
out/
sha512sums.txt
sha512sums.txt
pubkey.pem

View File

@@ -5,7 +5,7 @@ server:
go run cmd/uftp/main.go server
test:
go run cmd/uftp/main.go client testFiles/testFile 0.0.0.0:13374
go run cmd/uftp/main.go client testFiles/testFile 0.0.0.0
win:
GOOS=windows GOARCH=amd64 go build -o bin/app-amd64.exe cmd/uftp/main.go

View File

@@ -2,19 +2,23 @@ package client
import (
"crypto/rand"
"crypto/x509"
"encoding/hex"
"encoding/pem"
"errors"
"fmt"
"io"
"net"
"os"
"time"
"github.com/Pablu23/Uftp/internal/common"
"github.com/kelindar/bitmap"
"github.com/Pablu23/Uftp/internal/common"
)
func SendPacket(pck *common.Packet, key [32]byte, conn *net.UDPConn) {
secPck := common.NewSymetricSecurePacket(key, pck)
secPck := common.NewSymmetricSecurePacket(key, pck)
if _, err := conn.Write(secPck.ToBytes()); err != nil {
panic(err)
}
@@ -27,9 +31,11 @@ func ReceivePacket(key [32]byte, conn *net.UDPConn) common.Packet {
panic(err)
}
secPck := common.SecurePacketFromBytes(bytes)
secPck, err := common.SecurePacketFromBytes(bytes)
if err != nil {
panic(err)
}
pck, err := secPck.ExtractPacket(key)
if err != nil {
fmt.Println(bytes)
panic(err)
@@ -55,7 +61,10 @@ func ReceivePacketWithTimeout(key [32]byte, conn *net.UDPConn) (common.Packet, b
return common.Packet{}, false
}
secPck := common.SecurePacketFromBytes(bytes)
secPck, err := common.SecurePacketFromBytes(bytes)
if err != nil {
panic(err)
}
pck, err := secPck.ExtractPacket(key)
if err != nil {
panic(err)
@@ -64,6 +73,33 @@ func ReceivePacketWithTimeout(key [32]byte, conn *net.UDPConn) (common.Packet, b
return pck, true
}
func StartConnection(sid common.SessionID, key [32]byte, address string) {
pubkey, err := os.ReadFile("pubkey.pem")
if err != nil {
panic(err)
}
block, _ := pem.Decode(pubkey)
pKey, _ := x509.ParsePKCS1PublicKey(block.Bytes)
keyExchangePck, err := common.NewRsaPacket(pKey, key, sid)
if err != nil {
panic(err)
}
var d net.Dialer
conn, err := d.Dial("tcp", address)
if err != nil {
panic(err)
}
defer conn.Close()
conn.Write(keyExchangePck.ToBytes())
var buf [1024]byte
_, err = conn.Read(buf[:])
if err != nil && !errors.Is(err, io.EOF) {
panic(err)
}
}
func GetFile(path string, address string) {
request := common.NewRequest(path)
@@ -73,11 +109,11 @@ func GetFile(path string, address string) {
panic(err)
}
key := [32]byte(k)
keyExchangePck := common.NewRsaPacket(request.Sid, key)
StartConnection(request.Sid, key, fmt.Sprintf("%v:13375", address))
// udpAddr, err := net.ResolveUDPAddr("udp", "0.0.0.0:13374")
udpAddr, err := net.ResolveUDPAddr("udp", address)
udpAddr, err := net.ResolveUDPAddr("udp", fmt.Sprintf("%v:13374", address))
if err != nil {
fmt.Println(err)
os.Exit(1)
@@ -90,11 +126,6 @@ func GetFile(path string, address string) {
os.Exit(1)
}
_, err = conn.Write(keyExchangePck.ToBytes())
if err != nil {
panic(err)
}
SendPacket(request, key, conn)
file, err := os.Create("out/" + hex.EncodeToString(request.Sid[:]) + ".recv")

View File

@@ -0,0 +1,23 @@
package common
const PacketSize = 504
const (
HeaderSize int = 1 + 4
SecureHeaderSize int = 24 + 8 + 4
)
const MaxDataSize = PacketSize - HeaderSize - SecureHeaderSize - 16 // AEAD Overhead
type SessionID [8]byte
type HeaderFlag uint8
const (
Request HeaderFlag = iota
PTE HeaderFlag = iota
Ack HeaderFlag = iota
File HeaderFlag = iota
End HeaderFlag = iota
Resend HeaderFlag = iota
)

View File

@@ -5,27 +5,8 @@ import (
"encoding/binary"
"errors"
"fmt"
"golang.org/x/crypto/chacha20poly1305"
)
const PacketSize = 504
const HeaderSize int = 1 + 4
const SecureHeaderSize int = 1 + 24 + 8 + 4
const MaxDataSize = PacketSize - HeaderSize - SecureHeaderSize - 16 // AEAD Overhead
type SessionID [8]byte
type SecurePacket struct {
IsRsa byte // 0 = false everything else is true
Nonce [24]byte
Sid SessionID
DataLength uint32
EncryptedData []byte
}
type Packet struct {
Flag HeaderFlag
Sync uint32
@@ -36,88 +17,6 @@ type Packet struct {
DataLength uint32
}
func NewSymetricSecurePacket(key [32]byte, pck *Packet) *SecurePacket {
sid := pck.Sid
data := pck.ToBytes()
aead, err := chacha20poly1305.NewX(key[:])
if err != nil {
panic(err)
}
nonce := make([]byte, 24)
if _, err = rand.Read(nonce); err != nil {
panic(err)
}
encrypted := make([]byte, len(data)+aead.Overhead())
encrypted = aead.Seal(nil, nonce, data, nil)
return &SecurePacket{
IsRsa: 0,
Nonce: [24]byte(nonce),
Sid: sid,
DataLength: uint32(len(encrypted)),
EncryptedData: encrypted,
}
}
func SecurePacketFromBytes(bytes []byte) SecurePacket {
isRsa := bytes[0]
nonce := bytes[1:25]
sid := SessionID(bytes[25:33])
length := binary.LittleEndian.Uint32(bytes[33:37])
enc := bytes[37 : SecureHeaderSize+int(length)]
return SecurePacket{
IsRsa: isRsa,
Nonce: [24]byte(nonce),
Sid: sid,
DataLength: length,
EncryptedData: enc,
}
}
func (secPck *SecurePacket) ToBytes() []byte {
encSize := int(secPck.DataLength)
arr := make([]byte, SecureHeaderSize+encSize)
arr[0] = secPck.IsRsa
copy(arr[1:25], secPck.Nonce[:])
copy(arr[25:33], secPck.Sid[:])
binary.LittleEndian.PutUint32(arr[33:37], secPck.DataLength)
copy(arr[37:SecureHeaderSize+encSize], secPck.EncryptedData)
return arr
}
func (secPck *SecurePacket) ExtractPacket(key [32]byte) (Packet, error) {
aead, err := chacha20poly1305.NewX(key[:])
if err != nil {
panic(err)
}
data, err := aead.Open(nil, secPck.Nonce[:], secPck.EncryptedData, nil)
if err != nil {
return Packet{}, err
}
// fmt.Println(data)
packet := PacketFromBytes(data, secPck.DataLength-uint32(HeaderSize)-uint32(aead.Overhead()), secPck.Sid)
return packet, nil
}
func NewRsaPacket(sid SessionID, key [32]byte) *SecurePacket {
return &SecurePacket{
IsRsa: 1,
Nonce: [24]byte(make([]byte, 24)),
Sid: sid,
EncryptedData: key[:],
DataLength: 32,
}
}
func (secPck *SecurePacket) ExtractKey( /*RSA HERE LATER*/ ) []byte {
return secPck.EncryptedData[:32]
}
func PacketFromBytes(bytes []byte, dataLength uint32, sid SessionID) Packet {
flag := HeaderFlag(bytes[0])
sync := binary.LittleEndian.Uint32(bytes[1:5])
@@ -240,14 +139,3 @@ func (pck *Packet) ToBytes() []byte {
return arr
}
type HeaderFlag uint8
const (
Request HeaderFlag = iota
PTE HeaderFlag = iota
Ack HeaderFlag = iota
File HeaderFlag = iota
End HeaderFlag = iota
Resend HeaderFlag = iota
)

View File

@@ -55,9 +55,42 @@ func TestSymetricSecurePacket(t *testing.T) {
DataLength: 3,
}
key := [32]byte{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}
key := [32]byte{
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
}
secPck := NewSymetricSecurePacket(key, &expect)
secPck := NewSymmetricSecurePacket(key, &expect)
packet, err := secPck.ExtractPacket(key)
if err != nil {
@@ -71,8 +104,6 @@ func TestSymetricSecurePacket(t *testing.T) {
func TestSecurePacketFromBytes(t *testing.T) {
bytes := []byte{
//IsRsa
0,
// Nonce
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
// Sid
@@ -83,16 +114,44 @@ func TestSecurePacketFromBytes(t *testing.T) {
101, 10, 1,
}
secPck := SecurePacketFromBytes(bytes)
expect := SecurePacket{
IsRsa: 0,
Nonce: [24]byte{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1},
Nonce: [24]byte{
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
},
Sid: [8]byte{255, 255, 255, 255, 255, 255, 255, 255},
DataLength: 3,
EncryptedData: []byte{101, 10, 1},
}
secPck, err := SecurePacketFromBytes(bytes)
if err != nil {
t.Fail()
}
if !cmp.Equal(secPck, expect) {
t.Fail()
}
@@ -100,8 +159,6 @@ func TestSecurePacketFromBytes(t *testing.T) {
func TestSecurePacketToBytes(t *testing.T) {
expect := []byte{
//IsRsa
0,
// Nonce
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
// Sid
@@ -113,8 +170,32 @@ func TestSecurePacketToBytes(t *testing.T) {
}
secPck := SecurePacket{
IsRsa: 0,
Nonce: [24]byte{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1},
Nonce: [24]byte{
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
1,
},
Sid: [8]byte{255, 255, 255, 255, 255, 255, 255, 255},
DataLength: 3,
EncryptedData: []byte{101, 10, 1},

View File

@@ -0,0 +1,63 @@
package common
import (
"crypto"
"crypto/rand"
"crypto/rsa"
"crypto/sha256"
"encoding/binary"
)
type RsaPacket struct {
Sid SessionID
DataLength uint32
EncryptedKey []byte
}
func NewRsaPacket(pubKey *rsa.PublicKey, key [32]byte, sid SessionID) (*RsaPacket, error) {
enc, err := rsa.EncryptOAEP(sha256.New(), rand.Reader, pubKey, key[:], nil)
if err != nil {
return nil, err
}
pck := RsaPacket{
Sid: sid,
DataLength: uint32(len(enc)),
EncryptedKey: enc,
}
return &pck, nil
}
func (rsaPck *RsaPacket) ToBytes() []byte {
bytes := make([]byte, rsaPck.DataLength+8+4)
copy(bytes[0:8], rsaPck.Sid[:])
binary.LittleEndian.PutUint32(bytes[8:12], rsaPck.DataLength)
copy(bytes[12:], rsaPck.EncryptedKey[:])
return bytes
}
func RsaPacketFromBytes(bytes []byte) *RsaPacket {
sid := SessionID(bytes[0:8])
dLen := binary.LittleEndian.Uint32(bytes[8:12])
data := bytes[12 : 12+dLen]
return &RsaPacket{
Sid: sid,
DataLength: dLen,
EncryptedKey: data,
}
}
func (rsaPck *RsaPacket) ExtractKey(priv *rsa.PrivateKey) ([32]byte, error) {
// key, err := rsa.DecryptOAEP(sha256.New(), rand.Reader, priv, rsaPck.EncryptedKey, nil)
key, err := priv.Decrypt(
rand.Reader,
rsaPck.EncryptedKey,
&rsa.OAEPOptions{Hash: crypto.SHA256},
)
if err != nil {
return [32]byte{}, err
}
return [32]byte(key[0:32]), nil
}

View File

@@ -0,0 +1,87 @@
package common
import (
"crypto/rand"
"encoding/binary"
"errors"
"golang.org/x/crypto/chacha20poly1305"
)
type SecurePacket struct {
Nonce [24]byte
Sid SessionID
DataLength uint32
EncryptedData []byte
}
func NewSymmetricSecurePacket(key [32]byte, pck *Packet) *SecurePacket {
sid := pck.Sid
data := pck.ToBytes()
aead, err := chacha20poly1305.NewX(key[:])
if err != nil {
panic(err)
}
nonce := make([]byte, 24)
if _, err = rand.Read(nonce); err != nil {
panic(err)
}
encrypted := make([]byte, len(data)+aead.Overhead())
encrypted = aead.Seal(nil, nonce, data, nil)
return &SecurePacket{
Nonce: [24]byte(nonce),
Sid: sid,
DataLength: uint32(len(encrypted)),
EncryptedData: encrypted,
}
}
func SecurePacketFromBytes(bytes []byte) (*SecurePacket, error) {
nonce := bytes[:24]
sid := SessionID(bytes[24:32])
length := binary.LittleEndian.Uint32(bytes[32:36])
if SecureHeaderSize+int(length) > PacketSize {
return nil, errors.New("Packet too large")
}
enc := bytes[36 : SecureHeaderSize+int(length)]
return &SecurePacket{
Nonce: [24]byte(nonce),
Sid: sid,
DataLength: length,
EncryptedData: enc,
}, nil
}
func (secPck *SecurePacket) ToBytes() []byte {
encSize := int(secPck.DataLength)
arr := make([]byte, SecureHeaderSize+encSize)
copy(arr[0:24], secPck.Nonce[:])
copy(arr[24:32], secPck.Sid[:])
binary.LittleEndian.PutUint32(arr[32:36], secPck.DataLength)
copy(arr[36:SecureHeaderSize+encSize], secPck.EncryptedData)
return arr
}
func (secPck *SecurePacket) ExtractPacket(key [32]byte) (Packet, error) {
aead, err := chacha20poly1305.NewX(key[:])
if err != nil {
panic(err)
}
data, err := aead.Open(nil, secPck.Nonce[:], secPck.EncryptedData, nil)
if err != nil {
return Packet{}, err
}
// fmt.Println(data)
packet := PacketFromBytes(
data,
secPck.DataLength-uint32(HeaderSize)-uint32(aead.Overhead()),
secPck.Sid,
)
return packet, nil
}

View File

@@ -1,9 +1,12 @@
package server
import (
"bufio"
"crypto/rand"
"crypto/rsa"
"crypto/x509"
"encoding/hex"
"encoding/pem"
"errors"
"io"
"net"
@@ -12,9 +15,9 @@ import (
"sync"
"time"
"github.com/Pablu23/Uftp/internal/common"
log "github.com/sirupsen/logrus"
"github.com/Pablu23/Uftp/internal/common"
)
type info struct {
@@ -33,7 +36,6 @@ type Server struct {
func New() (*Server, error) {
key, err := rsa.GenerateKey(rand.Reader, 4096)
if err != nil {
return nil, err
}
@@ -48,6 +50,20 @@ func New() (*Server, error) {
}, nil
}
func (server *Server) SavePublicKeyPem() error {
file, err := os.Create("pubkey.pem")
if err != nil {
return err
}
defer file.Close()
publicKeyPEM := &pem.Block{
Type: "RSA PUBLIC KEY",
Bytes: x509.MarshalPKCS1PublicKey(&server.rsa.PublicKey),
}
pem.Encode(file, publicKeyPEM)
return nil
}
func (server *Server) sendPacket(conn *net.UDPConn, addr *net.UDPAddr, pck *common.Packet) {
server.mu.Lock()
var key [32]byte
@@ -61,7 +77,7 @@ func (server *Server) sendPacket(conn *net.UDPConn, addr *net.UDPAddr, pck *comm
return
}
secPck := common.NewSymetricSecurePacket(key, pck)
secPck := common.NewSymmetricSecurePacket(key, pck)
if _, err := conn.WriteToUDP(secPck.ToBytes(), addr); err != nil {
log.Error("Could not write Packet to UDP")
return
@@ -154,7 +170,6 @@ func (server *Server) handleAck(conn *net.UDPConn, addr *net.UDPAddr, pck *commo
server.mu.Unlock()
return
}
}
func (server *Server) sendPTE(conn *net.UDPConn, addr *net.UDPAddr, pck *common.Packet) {
@@ -189,7 +204,6 @@ func (server *Server) sendPTE(conn *net.UDPConn, addr *net.UDPAddr, pck *common.
}
func (server *Server) sendData(conn *net.UDPConn, addr *net.UDPAddr, pck *common.Packet) {
var path string
server.mu.Lock()
if info, ok := server.sessions[pck.Sid]; ok {
@@ -282,9 +296,51 @@ func (server *Server) handleShutdown(stop chan bool) {
}()
}
func (server *Server) handleConnection(conn net.Conn) {
reader := bufio.NewReader(conn)
var buf [2048]byte
r, err := reader.Read(buf[:])
if err != nil {
log.WithError(err).Warn("Could not read from Connection")
conn.Close()
return
}
// fmt.Println(buf)
rsaPck := common.RsaPacketFromBytes(buf[0:r])
key, err := rsaPck.ExtractKey(server.rsa)
if err != nil && !errors.Is(err, io.EOF) {
log.WithError(err).Warn("Could not extract Key")
return
}
server.mu.Lock()
server.sessions[rsaPck.Sid] = &info{
key: key,
}
server.mu.Unlock()
conn.Write([]byte("Yep"))
conn.Close()
}
func (server *Server) startManagement() {
listener, err := net.Listen("tcp", "0.0.0.0:13375")
if err != nil {
log.Fatal("Could not start listening on TCP 0.0.0.0:13375")
}
defer listener.Close()
for {
conn, err := listener.Accept()
if err != nil {
log.WithError(err).Warn("Could not accept TCP Connection")
}
go server.handleConnection(conn)
}
}
func (server *Server) Serve() {
udpAddr, err := net.ResolveUDPAddr("udp", "0.0.0.0:13374")
if err != nil {
log.Fatal("Could not resolve UDP Address")
}
@@ -301,6 +357,7 @@ func (server *Server) Serve() {
c := make(chan bool)
server.handleShutdown(c)
go server.startTimeout(c)
go server.startManagement()
for {
var buf [common.PacketSize]byte
@@ -310,32 +367,27 @@ func (server *Server) Serve() {
continue
}
secPck := common.SecurePacketFromBytes(buf[:])
if secPck.IsRsa == 0 {
var key [32]byte
server.mu.Lock()
if info, ok := server.sessions[secPck.Sid]; ok {
key = info.key
} else {
log.WithField("SessionID", hex.EncodeToString(secPck.Sid[:])).Warn("Invalid Session")
server.mu.Unlock()
continue
}
server.mu.Unlock()
pck, err := secPck.ExtractPacket(key)
if err != nil {
log.Error("Could not extract Packet from Secure Packet")
}
go server.handlePacket(conn, addr, &pck)
} else {
key := secPck.ExtractKey()
log.WithField("SessionID", hex.EncodeToString(secPck.Sid[:])).Info("New Session")
server.sessions[secPck.Sid] = &info{
key: [32]byte(key),
}
secPck, err := common.SecurePacketFromBytes(buf[:])
if err != nil {
log.WithError(err).Warn("Received invalid Packet")
continue
}
var key [32]byte
server.mu.Lock()
if info, ok := server.sessions[secPck.Sid]; ok {
key = info.key
} else {
log.WithField("SessionID", hex.EncodeToString(secPck.Sid[:])).Warn("Invalid Session")
server.mu.Unlock()
continue
}
pck, err := secPck.ExtractPacket(key)
if err != nil {
log.Error("Could not extract Packet from Secure Packet")
}
server.mu.Unlock()
go server.handlePacket(conn, addr, &pck)
}
}