1 files changed, 176 insertions, 0 deletions
diff --git a/internal/nymclient/manager.go b/internal/nymclient/manager.go
new file mode 100644
index 0000000..3c0b15d
--- /dev/null
+++ b/internal/nymclient/manager.go
@@ -0,0 +1,176 @@
+package nymclient
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"net"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+)
+
+type Config struct {
+	Binary           string
+	Provider         string
+	HomeDir          string
+	ClientID         string
+	SocksAddr        string
+	AnonymousReplies bool
+	StartupTimeout   time.Duration
+	LogOutput        io.Writer
+}
+
+type Manager struct {
+	cfg Config
+	cmd *exec.Cmd
+	mu  sync.Mutex
+}
+
+func New(cfg Config) (*Manager, error) {
+	if cfg.Binary == "" {
+		cfg.Binary = "nym-socks5-client"
+	}
+	if cfg.HomeDir == "" {
+		return nil, fmt.Errorf("nym home dir is required")
+	}
+	if cfg.ClientID == "" {
+		cfg.ClientID = "n2usenet"
+	}
+	if cfg.SocksAddr == "" {
+		cfg.SocksAddr = "127.0.0.1:11080"
+	}
+	if cfg.Provider == "" {
+		return nil, fmt.Errorf("nym provider is required")
+	}
+	if cfg.StartupTimeout <= 0 {
+		cfg.StartupTimeout = 120 * time.Second
+	}
+	if cfg.LogOutput == nil {
+		cfg.LogOutput = os.Stderr
+	}
+	return &Manager{cfg: cfg}, nil
+}
+
+func (m *Manager) Init(ctx context.Context) error {
+	binary, err := exec.LookPath(m.cfg.Binary)
+	if err != nil {
+		if _, statErr := os.Stat(m.cfg.Binary); statErr != nil {
+			return fmt.Errorf("find nym-socks5-client: %w", err)
+		}
+		binary = m.cfg.Binary
+	}
+	m.cfg.Binary = binary
+
+	if err := os.MkdirAll(m.cfg.HomeDir, 0700); err != nil {
+		return fmt.Errorf("create nym home: %w", err)
+	}
+
+	configFile := filepath.Join(m.cfg.HomeDir, ".nym", "socks5-clients", m.cfg.ClientID, "config", "config.toml")
+	if data, err := os.ReadFile(configFile); err == nil {
+		if !strings.Contains(string(data), m.cfg.Provider) {
+			return fmt.Errorf("existing nym client config uses a different provider; remove %s to reinitialize intentionally", filepath.Dir(filepath.Dir(configFile)))
+		}
+		return nil
+	}
+
+	host, port, err := net.SplitHostPort(m.cfg.SocksAddr)
+	if err != nil {
+		return fmt.Errorf("split socks addr: %w", err)
+	}
+
+	args := []string{
+		"init",
+		"--id", m.cfg.ClientID,
+		"--provider", m.cfg.Provider,
+		"--host", host,
+		"--port", port,
+	}
+	if m.cfg.AnonymousReplies {
+		args = append(args, "--use-reply-surbs", "true")
+	}
+
+	cmd := exec.CommandContext(ctx, m.cfg.Binary, args...)
+	cmd.Env = append(os.Environ(), "HOME="+m.cfg.HomeDir)
+	cmd.Stdout = m.cfg.LogOutput
+	cmd.Stderr = m.cfg.LogOutput
+	if err := cmd.Run(); err != nil {
+		return fmt.Errorf("nym-socks5-client init: %w", err)
+	}
+	return nil
+}
+
+func (m *Manager) Start(ctx context.Context) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if m.cmd != nil {
+		return nil
+	}
+
+	host, port, err := net.SplitHostPort(m.cfg.SocksAddr)
+	if err != nil {
+		return fmt.Errorf("split socks addr: %w", err)
+	}
+
+	args := []string{"run", "--id", m.cfg.ClientID, "--host", host, "--port", port}
+	if m.cfg.AnonymousReplies {
+		args = append(args, "--use-anonymous-replies", "true")
+	}
+
+	cmd := exec.CommandContext(ctx, m.cfg.Binary, args...)
+	cmd.Env = append(os.Environ(), "HOME="+m.cfg.HomeDir)
+	cmd.Stdout = m.cfg.LogOutput
+	cmd.Stderr = m.cfg.LogOutput
+	if err := cmd.Start(); err != nil {
+		return fmt.Errorf("start nym-socks5-client: %w", err)
+	}
+	m.cmd = cmd
+
+	go func() {
+		_ = cmd.Wait()
+	}()
+
+	deadline := time.Now().Add(m.cfg.StartupTimeout)
+	for {
+		dialCtx, cancel := context.WithTimeout(ctx, 500*time.Millisecond)
+		conn, err := (&net.Dialer{}).DialContext(dialCtx, "tcp", m.cfg.SocksAddr)
+		cancel()
+		if err == nil {
+			_ = conn.Close()
+			return nil
+		}
+		if time.Now().After(deadline) {
+			m.Stop()
+			return fmt.Errorf("nym-socks5-client did not open %s within %s", m.cfg.SocksAddr, m.cfg.StartupTimeout)
+		}
+		select {
+		case <-ctx.Done():
+			m.Stop()
+			return ctx.Err()
+		case <-time.After(500 * time.Millisecond):
+		}
+	}
+}
+
+func (m *Manager) Stop() {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if m.cmd == nil || m.cmd.Process == nil {
+		return
+	}
+	_ = m.cmd.Process.Signal(os.Interrupt)
+	done := make(chan struct{})
+	go func() {
+		_ = m.cmd.Wait()
+		close(done)
+	}()
+	select {
+	case <-done:
+	case <-time.After(5 * time.Second):
+		_ = m.cmd.Process.Kill()
+	}
+	m.cmd = nil
+}