diff --git a/go.mod b/go.mod index 44a589e..3ac05cb 100644 --- a/go.mod +++ b/go.mod @@ -9,7 +9,7 @@ require ( github.com/spf13/cobra v1.10.2 github.com/spf13/viper v1.21.0 go.uber.org/zap v1.24.0 - golang.org/x/crypto v0.47.0 + golang.org/x/crypto v0.53.0 ) require ( @@ -24,8 +24,8 @@ require ( github.com/subosito/gotenv v1.6.0 // indirect go.uber.org/atomic v1.11.0 // indirect go.uber.org/multierr v1.11.0 // indirect - golang.org/x/sys v0.41.0 // indirect - golang.org/x/text v0.34.0 // indirect + golang.org/x/sys v0.46.0 // indirect + golang.org/x/text v0.38.0 // indirect ) require ( @@ -34,8 +34,11 @@ require ( github.com/mholt/acmez v1.0.4 // indirect github.com/miekg/dns v1.1.50 // indirect go.yaml.in/yaml/v3 v3.0.4 // indirect - golang.org/x/mod v0.32.0 // indirect - golang.org/x/net v0.49.0 // indirect - golang.org/x/sync v0.19.0 // indirect - golang.org/x/tools v0.41.0 // indirect + golang.org/x/mobile v0.0.0-20260611195102-4dd8f1dbf5d2 // indirect + golang.org/x/mod v0.37.0 // indirect + golang.org/x/net v0.56.0 // indirect + golang.org/x/sync v0.21.0 // indirect + golang.org/x/tools v0.46.0 // indirect ) + +tool golang.org/x/mobile/cmd/gobind diff --git a/go.sum b/go.sum index 7973fee..d6c226a 100644 --- a/go.sum +++ b/go.sum @@ -84,10 +84,16 @@ golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACk golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI= golang.org/x/crypto v0.47.0 h1:V6e3FRj+n4dbpw86FJ8Fv7XVOql7TEwpHapKoMJ/GO8= golang.org/x/crypto v0.47.0/go.mod h1:ff3Y9VzzKbwSSEzWqJsJVBnWmRwRSHt/6Op5n9bQc4A= +golang.org/x/crypto v0.53.0 h1:QZ4Muo8THX6CizN2vPPd5fBGHyogrdK9fG4wLPFUsto= +golang.org/x/crypto v0.53.0/go.mod h1:DNLU434OwVakk9PzuwV8w62mAJpRJL3vsgcfp4Qnsio= golang.org/x/lint v0.0.0-20190930215403-16217165b5de/go.mod h1:6SW0HCj/g11FgYtHlgUYUwCkIfeOF89ocIRzGO/8vkc= +golang.org/x/mobile v0.0.0-20260611195102-4dd8f1dbf5d2 h1:zoM1gIKhVkcQNm43kad8OHLgPNoJ12xIqmxHtKr8Mug= +golang.org/x/mobile v0.0.0-20260611195102-4dd8f1dbf5d2/go.mod h1:QGMqsqLn6orFQ/ksqYMf+Fa33Soa1vPoHEd0Pj7N+lQ= golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA= golang.org/x/mod v0.32.0 h1:9F4d3PHLljb6x//jOyokMv3eX+YDeepZSEo3mFJy93c= golang.org/x/mod v0.32.0/go.mod h1:SgipZ/3h2Ci89DlEtEXWUk/HteuRin+HHhN+WbNhguU= +golang.org/x/mod v0.37.0 h1:vF1DjpVEshcIqoEaauuHebaLk1O1forxjxBaVn884JQ= +golang.org/x/mod v0.37.0/go.mod h1:m8S8VeM9r4dzDwjrKO0a1sZP3YjeMamRRlD+fmR2Q/0= golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg= golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg= golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s= @@ -96,10 +102,14 @@ golang.org/x/net v0.0.0-20210726213435-c6fcb2dbf985/go.mod h1:9nx3DQGgdP8bBQD5qx golang.org/x/net v0.0.0-20220630215102-69896b714898/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c= golang.org/x/net v0.49.0 h1:eeHFmOGUTtaaPSGNmjBKpbng9MulQsJURQUAfUwY++o= golang.org/x/net v0.49.0/go.mod h1:/ysNB2EvaqvesRkuLAyjI1ycPZlQHM3q01F02UY/MV8= +golang.org/x/net v0.56.0 h1:Rw8j/hFzGvJUZwNBXnAtf5sVDVt+65SK2C7IxCxZt5o= +golang.org/x/net v0.56.0/go.mod h1:D3Ku6r+V6JROoZK144D2XfMHFcMq/0zSfLelVTCFKec= golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM= golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM= golang.org/x/sync v0.19.0 h1:vV+1eWNmZ5geRlYjzm2adRgW2/mcpevXNg50YZtPCE4= golang.org/x/sync v0.19.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI= +golang.org/x/sync v0.21.0 h1:HLII4xRRTtCRkxYp4HNFF0Js/Og6q2i++KXbg0gHCwM= +golang.org/x/sync v0.21.0/go.mod h1:9xrNwdLfx4jkKbNva9FpL6vEN7evnE43NNNJQ2LF3+0= golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY= golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs= golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs= @@ -112,6 +122,8 @@ golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBc golang.org/x/sys v0.0.0-20220704084225-05e143d24a9e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k= golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks= +golang.org/x/sys v0.46.0 h1:noSf2Fq6F8DBgS+LysIkx7rIExoNHJsxOAtPp4rthXw= +golang.org/x/sys v0.46.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw= golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo= golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8= golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ= @@ -120,6 +132,8 @@ golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ= golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ= golang.org/x/text v0.34.0 h1:oL/Qq0Kdaqxa1KbNeMKwQq0reLCCaFtqu2eNuSeNHbk= golang.org/x/text v0.34.0/go.mod h1:homfLqTYRFyVYemLBFl5GgL/DWEiH5wcsQ5gSh1yziA= +golang.org/x/text v0.38.0 h1:sXmwo9DwP3OK9EZ7PqAdaooSGozfl/3a6/xJcbzPRhE= +golang.org/x/text v0.38.0/go.mod h1:YXZt3QhHUKYT53r2lLKFIVi6Ao1jdzrTR/KQ09qyxF4= golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ= golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs= golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo= @@ -127,6 +141,8 @@ golang.org/x/tools v0.1.5/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk= golang.org/x/tools v0.1.6-0.20210726203631-07bc1bf47fb2/go.mod h1:o0xws9oXOQQZyjljx8fwUC0k7L1pTE6eaCbjGeHmOkk= golang.org/x/tools v0.41.0 h1:a9b8iMweWG+S0OBnlU36rzLp20z1Rp10w+IY2czHTQc= golang.org/x/tools v0.41.0/go.mod h1:XSY6eDqxVNiYgezAVqqCeihT4j1U2CCsqvH3WhQpnlg= +golang.org/x/tools v0.46.0 h1:7jTurBkPZu4moS/Uy4OQT1M+QBlsj3wejyZwsT8Z7rk= +golang.org/x/tools v0.46.0/go.mod h1:FrD85F8l+NWL+9XWBSyVSHO6Ne4jutsfIFba7AWQ5Ys= golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0= golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0= golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0= diff --git a/internal/server/server.go b/internal/server/server.go index efc77d5..ddfd9bd 100644 --- a/internal/server/server.go +++ b/internal/server/server.go @@ -138,7 +138,8 @@ func (s *Server) setupTLS() (*tls.Config, error) { if len(s.cfg.ACME.Domains) == 0 || s.cfg.ACME.Email == "" { s.logger.Warn("ACME not configured, starting without TLS (insecure)") return &tls.Config{ - MinVersion: tls.VersionTLS13, + MinVersion: tls.VersionTLS13, + NextProtos: []string{"qcc"}, InsecureSkipVerify: true, }, nil } diff --git a/internal/transport/server.go b/internal/transport/server.go index 4d8b44e..e638d2d 100644 --- a/internal/transport/server.go +++ b/internal/transport/server.go @@ -107,6 +107,7 @@ func NewTLSConfig(domains []string, email, caType string, dnsSolver *certmagic.D return &tls.Config{ MinVersion: tls.VersionTLS13, + NextProtos: []string{"qcc"}, GetCertificate: cmCfg.GetCertificate, }, nil } diff --git a/mobile/client.go b/mobile/client.go new file mode 100644 index 0000000..398f7c7 --- /dev/null +++ b/mobile/client.go @@ -0,0 +1,706 @@ +package mobile + +import ( + "context" + "crypto/ed25519" + "crypto/rand" + "crypto/sha256" + "crypto/tls" + "crypto/x509" + "encoding/binary" + "fmt" + "io" + "net" + "sync" + "time" + + "github.com/apernet/quic-go" + "github.com/niko/qcc/internal/auth" + "github.com/niko/qcc/internal/protocol" + "github.com/niko/qcc/pkg/types" + "golang.org/x/crypto/chacha20poly1305" + "golang.org/x/crypto/curve25519" + "golang.org/x/crypto/hkdf" +) + +type Client struct { + mu sync.Mutex + conn *quic.Conn + transport *quic.Transport + udpConn net.PacketConn + + privKey ed25519.PrivateKey + pubKey ed25519.PublicKey + + number string + certDER []byte + caCertDER []byte + + serverAddr string + + callbacks Callbacks + + ctx context.Context + cancel context.CancelFunc + + e2eePriv [32]byte + e2eePub [32]byte + mediaKey []byte + activeCall bool + callID uint64 + + authOpened bool +} + +type Callbacks interface { + OnIncomingCall(number string) + OnCallAccepted() + OnCallEnded() + OnCallRejected() + OnError(msg string) + OnMedia(data []byte) +} + +func NewClient() *Client { + pub, priv, _ := ed25519.GenerateKey(rand.Reader) + return &Client{ + privKey: priv, + pubKey: pub, + } +} + +func (c *Client) SetCallbacks(cbs Callbacks) { + c.mu.Lock() + defer c.mu.Unlock() + c.callbacks = cbs +} + +func (c *Client) Connect(addr string) error { + c.mu.Lock() + defer c.mu.Unlock() + + c.serverAddr = addr + + host, _, err := net.SplitHostPort(addr) + if err != nil { + host = addr + } + + tlsConf := &tls.Config{ + ServerName: host, + InsecureSkipVerify: true, + NextProtos: []string{"qcc"}, + MinVersion: tls.VersionTLS13, + } + + udpAddr, err := net.ResolveUDPAddr("udp", addr) + if err != nil { + return fmt.Errorf("resolve addr: %w", err) + } + + udpConn, err := net.ListenUDP("udp", nil) + if err != nil { + return fmt.Errorf("listen udp: %w", err) + } + c.udpConn = udpConn + + tr := &quic.Transport{Conn: udpConn} + c.transport = tr + + ctx := context.Background() + conn, err := tr.Dial(ctx, udpAddr, tlsConf, &quic.Config{ + EnableDatagrams: true, + KeepAlivePeriod: 15 * time.Second, + }) + if err != nil { + udpConn.Close() + c.transport = nil + c.udpConn = nil + return fmt.Errorf("quic dial: %w", err) + } + + c.conn = conn + c.ctx, c.cancel = context.WithCancel(ctx) + + return nil +} + +func (c *Client) Authenticate() (string, error) { + c.mu.Lock() + conn := c.conn + c.mu.Unlock() + + if conn == nil { + return "", fmt.Errorf("not connected") + } + + authSt, err := conn.OpenStream() + if err != nil { + return "", fmt.Errorf("open auth stream: %w", err) + } + + if err := protocol.WriteFrame(authSt, byte(types.OpGetChallenge), nil); err != nil { + authSt.Close() + return "", fmt.Errorf("send challenge: %w", err) + } + + frame, err := protocol.ReadFrame(authSt) + if err != nil { + authSt.Close() + return "", fmt.Errorf("read challenge: %w", err) + } + + if types.OpCode(frame.OpCode) != types.OpChallenge { + authSt.Close() + return "", fmt.Errorf("expected challenge, got op=%x", frame.OpCode) + } + + challenge := auth.UnmarshalChallenge(frame.Payload) + if challenge == nil { + authSt.Close() + return "", fmt.Errorf("invalid challenge payload") + } + + solution := c.solvePoW(challenge) + if solution == nil { + authSt.Close() + return "", fmt.Errorf("PoW solve failed") + } + + solnPayload := make([]byte, 40) + copy(solnPayload[0:8], solution.ClientNonce[:]) + copy(solnPayload[8:40], solution.ClientPubKey[:]) + + if err := protocol.WriteFrame(authSt, byte(types.OpSolve), solnPayload); err != nil { + authSt.Close() + return "", fmt.Errorf("send solution: %w", err) + } + + frame, err = protocol.ReadFrame(authSt) + if err != nil { + authSt.Close() + return "", fmt.Errorf("read response: %w", err) + } + + if types.OpCode(frame.OpCode) == types.OpError { + authSt.Close() + errMsg := parseError(frame.Payload) + return "", fmt.Errorf("server error: %s", errMsg) + } + + if types.OpCode(frame.OpCode) != types.OpIdentity { + authSt.Close() + return "", fmt.Errorf("expected identity, got op=%x", frame.OpCode) + } + + number, certDER, caCertDER := parseIdentityPayload(frame.Payload) + if number == "" { + authSt.Close() + return "", fmt.Errorf("invalid identity payload") + } + + c.mu.Lock() + c.number = number + c.certDER = certDER + c.caCertDER = caCertDER + c.authOpened = true + c.mu.Unlock() + + go c.handleIncomingStreams() + + return number, nil +} + +func (c *Client) solvePoW(challenge *auth.PoWChallenge) *auth.PoWSolution { + bits := challenge.Bits + var nonceCounter uint64 + + var solution auth.PoWSolution + copy(solution.ClientPubKey[:], c.pubKey) + + hashInput := make([]byte, 32) + binary.BigEndian.PutUint64(hashInput[0:8], uint64(challenge.Timestamp)) + copy(hashInput[8:16], challenge.ServerNonce[:]) + + for { + binary.BigEndian.PutUint64(hashInput[16:24], nonceCounter) + copy(hashInput[24:], solution.ClientPubKey[:]) + + hash := sha256.Sum256(hashInput) + + leadingZeros := 0 + for i := 0; i < 32; i++ { + if hash[i] == 0 { + leadingZeros += 8 + } else { + for b := byte(0x80); b != 0; b >>= 1 { + if hash[i]&b == 0 { + leadingZeros++ + } else { + goto checkDone + } + } + } + } + checkDone: + if leadingZeros >= bits { + binary.BigEndian.PutUint64(solution.ClientNonce[:], nonceCounter) + return &solution + } + nonceCounter++ + } +} + +func (c *Client) MyNumber() string { + c.mu.Lock() + defer c.mu.Unlock() + return c.number +} + +func (c *Client) ServerAddr() string { + c.mu.Lock() + defer c.mu.Unlock() + return c.serverAddr +} + +func (c *Client) IsConnected() bool { + c.mu.Lock() + defer c.mu.Unlock() + return c.conn != nil +} + +func (c *Client) Disconnect() { + c.mu.Lock() + defer c.mu.Unlock() + + if c.cancel != nil { + c.cancel() + } + if c.conn != nil { + c.conn.CloseWithError(0, "client disconnect") + } + if c.transport != nil { + c.transport.Close() + } + if c.udpConn != nil { + c.udpConn.Close() + } + c.conn = nil + c.transport = nil + c.udpConn = nil + c.number = "" + c.certDER = nil + c.caCertDER = nil + c.activeCall = false + c.callID = 0 + c.mediaKey = nil + c.authOpened = false +} + +func (c *Client) handleIncomingStreams() { + c.mu.Lock() + conn := c.conn + ctx := c.ctx + c.mu.Unlock() + + if conn == nil { + return + } + + for { + st, err := conn.AcceptStream(ctx) + if err != nil { + return + } + go c.handleStream(st) + } +} + +func (c *Client) handleStream(st *quic.Stream) { + defer st.Close() + + for { + frame, err := protocol.ReadFrame(st) + if err != nil { + return + } + + switch types.OpCode(frame.OpCode) { + case types.OpRing: + number, callerE2EE := parseRingPayload(frame.Payload) + c.mu.Lock() + c.e2eePub = callerE2EE + c.mu.Unlock() + if c.callbacks != nil { + c.callbacks.OnIncomingCall(number) + } + + case types.OpPeerAccept: + var peerE2EE [32]byte + if len(frame.Payload) >= 32 { + copy(peerE2EE[:], frame.Payload[:32]) + } + c.mu.Lock() + c.e2eePub = peerE2EE + c.deriveMediaKey() + c.activeCall = true + c.mu.Unlock() + if c.callbacks != nil { + c.callbacks.OnCallAccepted() + } + + case types.OpPeerEnd: + c.mu.Lock() + c.activeCall = false + c.callID = 0 + c.mediaKey = nil + c.mu.Unlock() + if c.callbacks != nil { + c.callbacks.OnCallEnded() + } + + case types.OpError: + errMsg := parseError(frame.Payload) + if c.callbacks != nil { + c.callbacks.OnError(errMsg) + } + return + } + } +} + +func (c *Client) handleDatagrams() { + c.mu.Lock() + conn := c.conn + ctx := c.ctx + c.mu.Unlock() + + if conn == nil { + return + } + + for { + data, err := conn.ReceiveDatagram(ctx) + if err != nil { + return + } + + pkt, ok := protocol.UnmarshalMediaPacket(data) + if !ok { + continue + } + + c.mu.Lock() + cid := c.callID + key := c.mediaKey + c.mu.Unlock() + + if pkt.CallID != cid { + continue + } + + if key != nil && len(pkt.Payload) > 0 { + decrypted, err := decryptE2EE(key, pkt.Payload) + if err == nil { + if c.callbacks != nil { + c.callbacks.OnMedia(decrypted) + } + } + } + } +} + +func (c *Client) Dial(number string) error { + c.mu.Lock() + conn := c.conn + c.mu.Unlock() + if conn == nil { + return fmt.Errorf("not connected") + } + + e2eeKP, err := generateE2EEKey() + if err != nil { + return fmt.Errorf("generate e2ee key: %w", err) + } + + c.mu.Lock() + c.e2eePriv = e2eeKP.PrivateKey + c.mu.Unlock() + + payload := make([]byte, 1+len(number)+32) + payload[0] = byte(len(number)) + copy(payload[1:], number) + copy(payload[1+len(number):], e2eeKP.PublicKey[:]) + + st, err := conn.OpenStream() + if err != nil { + return fmt.Errorf("open call stream: %w", err) + } + + if err := protocol.WriteFrame(st, byte(types.OpDial), payload); err != nil { + st.Close() + return fmt.Errorf("send dial: %w", err) + } + + go func() { + defer st.Close() + c.handleStream(st) + }() + + return nil +} + +func (c *Client) AcceptCall() error { + e2eeKP, err := generateE2EEKey() + if err != nil { + return err + } + + c.mu.Lock() + c.e2eePriv = e2eeKP.PrivateKey + c.mu.Unlock() + + payload := make([]byte, 32) + copy(payload, e2eeKP.PublicKey[:]) + + c.mu.Lock() + conn := c.conn + c.mu.Unlock() + if conn == nil { + return fmt.Errorf("not connected") + } + + st, err := conn.OpenStream() + if err != nil { + return fmt.Errorf("open stream: %w", err) + } + + if err := protocol.WriteFrame(st, byte(types.OpAccept), payload); err != nil { + st.Close() + return fmt.Errorf("send accept: %w", err) + } + + go func() { + defer st.Close() + c.handleStream(st) + }() + + return nil +} + +func (c *Client) RejectCall() error { + c.mu.Lock() + conn := c.conn + c.mu.Unlock() + if conn == nil { + return nil + } + + st, err := conn.OpenStream() + if err != nil { + return err + } + defer st.Close() + + return protocol.WriteFrame(st, byte(types.OpReject), nil) +} + +func (c *Client) EndCall() error { + c.mu.Lock() + conn := c.conn + c.activeCall = false + c.callID = 0 + c.mediaKey = nil + c.mu.Unlock() + + if conn == nil { + return nil + } + + st, err := conn.OpenStream() + if err != nil { + return err + } + defer st.Close() + + return protocol.WriteFrame(st, byte(types.OpEnd), nil) +} + +func (c *Client) SendMedia(data []byte) error { + c.mu.Lock() + if !c.activeCall { + c.mu.Unlock() + return fmt.Errorf("no active call") + } + key := c.mediaKey + cid := c.callID + conn := c.conn + c.mu.Unlock() + + if key == nil { + return fmt.Errorf("no media key") + } + if conn == nil { + return fmt.Errorf("not connected") + } + + encrypted, err := encryptE2EE(key, data) + if err != nil { + return fmt.Errorf("encrypt: %w", err) + } + + pkt := &protocol.MediaPacket{ + CallID: cid, + Payload: encrypted, + } + + raw := protocol.MarshalMediaPacket(pkt) + return conn.SendDatagram(raw) +} + +func (c *Client) StartMediaLoop() { + go c.handleDatagrams() +} + +func (c *Client) deriveMediaKey() { + shared, err := curve25519.X25519(c.e2eePriv[:], c.e2eePub[:]) + if err != nil { + return + } + salt := make([]byte, 32) + info := []byte("qcc-e2ee-media-key") + kdf := hkdf.New(sha256.New, shared, salt, info) + key := make([]byte, 32) + if _, err := io.ReadFull(kdf, key); err != nil { + return + } + c.mediaKey = key +} + +type e2eeKeypair struct { + PrivateKey [32]byte + PublicKey [32]byte +} + +func generateE2EEKey() (*e2eeKeypair, error) { + priv := make([]byte, 32) + if _, err := io.ReadFull(rand.Reader, priv); err != nil { + return nil, err + } + priv[0] &= 248 + priv[31] &= 127 + priv[31] |= 64 + + pub, err := curve25519.X25519(priv, curve25519.Basepoint) + if err != nil { + return nil, err + } + + var result e2eeKeypair + copy(result.PrivateKey[:], priv) + copy(result.PublicKey[:], pub) + return &result, nil +} + +func encryptE2EE(key, plaintext []byte) ([]byte, error) { + aead, err := chacha20poly1305.New(key) + if err != nil { + return nil, err + } + nonce := make([]byte, chacha20poly1305.NonceSizeX) + if _, err := io.ReadFull(rand.Reader, nonce); err != nil { + return nil, err + } + return aead.Seal(nonce, nonce, plaintext, nil), nil +} + +func decryptE2EE(key, ciphertext []byte) ([]byte, error) { + aead, err := chacha20poly1305.New(key) + if err != nil { + return nil, err + } + if len(ciphertext) < chacha20poly1305.NonceSizeX { + return nil, io.ErrUnexpectedEOF + } + nonce := ciphertext[:chacha20poly1305.NonceSizeX] + return aead.Open(nil, nonce, ciphertext[chacha20poly1305.NonceSizeX:], nil) +} + +func parseError(payload []byte) string { + if len(payload) < 2 { + return "unknown error" + } + return string(payload[2:]) +} + +func parseIdentityPayload(data []byte) (string, []byte, []byte) { + if len(data) < 3 { + return "", nil, nil + } + off := 0 + for off < len(data) && data[off] != 0 { + off++ + } + if off >= len(data) { + return "", nil, nil + } + number := string(data[:off]) + off++ + + if off+2 > len(data) { + return number, nil, nil + } + certLen := int(binary.BigEndian.Uint16(data[off:])) + off += 2 + if off+certLen > len(data) { + return number, nil, nil + } + certDER := make([]byte, certLen) + copy(certDER, data[off:off+certLen]) + off += certLen + + caCertDER := make([]byte, len(data)-off) + copy(caCertDER, data[off:]) + + return number, certDER, caCertDER +} + +func parseRingPayload(data []byte) (string, [32]byte) { + if len(data) < 1 { + return "", [32]byte{} + } + numLen := int(data[0]) + if len(data) < 1+numLen+32 { + return "", [32]byte{} + } + number := string(data[1 : 1+numLen]) + var e2eePub [32]byte + copy(e2eePub[:], data[1+numLen:1+numLen+32]) + return number, e2eePub +} + +func (c *Client) VerifyCertificate() bool { + if len(c.caCertDER) == 0 || len(c.certDER) == 0 { + return false + } + + caCert, err := x509.ParseCertificate(c.caCertDER) + if err != nil { + return false + } + + cert, err := x509.ParseCertificate(c.certDER) + if err != nil { + return false + } + + roots := x509.NewCertPool() + roots.AddCert(caCert) + + opts := x509.VerifyOptions{ + Roots: roots, + } + + _, err = cert.Verify(opts) + return err == nil +}