fscan/Plugins/services/ssh/exploiter.go

package ssh

import (
	"context"
	"fmt"
	"github.com/shadow1ng/fscan/common"
	"github.com/shadow1ng/fscan/common/i18n"
	"github.com/shadow1ng/fscan/plugins/base"
	"golang.org/x/crypto/ssh"
	"strings"
)

// SSHExploiter SSH利用器实现
type SSHExploiter struct {
	*base.BaseExploiter
	connector *SSHConnector
}

// NewSSHExploiter 创建SSH利用器
func NewSSHExploiter() *SSHExploiter {
	exploiter := &SSHExploiter{
		BaseExploiter: base.NewBaseExploiter("ssh"),
		connector:     NewSSHConnector(),
	}
	
	// 添加利用方法
	exploiter.setupExploitMethods()
	
	return exploiter
}

// setupExploitMethods 设置利用方法
func (e *SSHExploiter) setupExploitMethods() {
	// 1. 系统信息收集
	infoMethod := base.NewExploitMethod(base.ExploitDataExtraction, "system_info").
		WithDescription("收集系统信息").
		WithPriority(8).
		WithConditions("has_credentials").
		WithHandler(e.exploitSystemInfo).
		Build()
	e.AddExploitMethod(infoMethod)
	
	// 2. 命令执行测试
	cmdMethod := base.NewExploitMethod(base.ExploitCommandExec, "command_test").
		WithDescription("测试命令执行能力").
		WithPriority(9).
		WithConditions("has_credentials").
		WithHandler(e.exploitCommandTest).
		Build()
	e.AddExploitMethod(cmdMethod)
	
	// 3. 用户权限检查
	privMethod := base.NewExploitMethod(base.ExploitDataExtraction, "privilege_check").
		WithDescription("检查用户权限").
		WithPriority(7).
		WithConditions("has_credentials").
		WithHandler(e.exploitPrivilegeCheck).
		Build()
	e.AddExploitMethod(privMethod)
}

// exploitSystemInfo 系统信息收集利用
func (e *SSHExploiter) exploitSystemInfo(ctx context.Context, info *common.HostInfo, creds *base.Credential) (*base.ExploitResult, error) {
	client, err := e.connectSSH(ctx, info, creds)
	if err != nil {
		return base.CreateFailedExploitResult(base.ExploitDataExtraction, "system_info", err), nil
	}
	defer client.Close()
	
	result := base.CreateSuccessExploitResult(base.ExploitDataExtraction, "system_info")
	
	// 收集系统信息的命令
	commands := map[string]string{
		"hostname": "hostname",
		"os":       "cat /etc/os-release 2>/dev/null || uname -a",
		"whoami":   "whoami",
		"id":       "id",
		"uptime":   "uptime",
		"pwd":      "pwd",
	}
	
	for name, cmd := range commands {
		output, err := e.executeCommand(client, cmd)
		if err == nil && output != "" {
			base.AddOutputToResult(result, i18n.GetText("ssh_command_result", name, strings.TrimSpace(output)))
			result.Extra[name] = strings.TrimSpace(output)
		}
	}
	
	return result, nil
}

// exploitCommandTest 命令执行测试利用
func (e *SSHExploiter) exploitCommandTest(ctx context.Context, info *common.HostInfo, creds *base.Credential) (*base.ExploitResult, error) {
	client, err := e.connectSSH(ctx, info, creds)
	if err != nil {
		return base.CreateFailedExploitResult(base.ExploitCommandExec, "command_test", err), nil
	}
	defer client.Close()
	
	result := base.CreateSuccessExploitResult(base.ExploitCommandExec, "command_test")
	
	// 测试基本命令执行
	testCommands := []string{"echo 'SSH_COMMAND_TEST'", "date", "whoami"}
	
	for _, cmd := range testCommands {
		output, err := e.executeCommand(client, cmd)
		if err == nil && output != "" {
			base.AddOutputToResult(result, i18n.GetText("ssh_test_command", cmd, strings.TrimSpace(output)))
		}
	}
	
	return result, nil
}

// exploitPrivilegeCheck 权限检查利用
func (e *SSHExploiter) exploitPrivilegeCheck(ctx context.Context, info *common.HostInfo, creds *base.Credential) (*base.ExploitResult, error) {
	client, err := e.connectSSH(ctx, info, creds)
	if err != nil {
		return base.CreateFailedExploitResult(base.ExploitDataExtraction, "privilege_check", err), nil
	}
	defer client.Close()
	
	result := base.CreateSuccessExploitResult(base.ExploitDataExtraction, "privilege_check")
	
	// 检查sudo权限
	sudoOutput, err := e.executeCommand(client, "sudo -l 2>/dev/null")
	if err == nil && sudoOutput != "" && !strings.Contains(sudoOutput, "may not run sudo") {
		base.AddOutputToResult(result, i18n.GetText("ssh_sudo_check", strings.TrimSpace(sudoOutput)))
		result.Extra["sudo_privileges"] = strings.TrimSpace(sudoOutput)
	}
	
	// 检查是否为root用户
	whoami, err := e.executeCommand(client, "whoami")
	if err == nil && strings.TrimSpace(whoami) == "root" {
		base.AddOutputToResult(result, i18n.GetText("ssh_root_access"))
		result.Extra["is_root"] = true
	}
	
	// 检查用户组
	groups, err := e.executeCommand(client, "groups")
	if err == nil && groups != "" {
		base.AddOutputToResult(result, i18n.GetText("ssh_user_groups", strings.TrimSpace(groups)))
		result.Extra["groups"] = strings.TrimSpace(groups)
	}
	
	return result, nil
}

// =============================================================================
// SSH操作辅助函数
// =============================================================================

// connectSSH 使用凭据连接SSH
func (e *SSHExploiter) connectSSH(ctx context.Context, info *common.HostInfo, creds *base.Credential) (*ssh.Client, error) {
	config := &ssh.ClientConfig{
		Timeout:         0, // 禁用SSH库超时，使用Context控制
		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
	}
	
	// 设置认证方法
	if creds.KeyData != nil && len(creds.KeyData) > 0 {
		// 密钥认证
		signer, err := ssh.ParsePrivateKey(creds.KeyData)
		if err != nil {
			return nil, fmt.Errorf("解析私钥失败: %v", err)
		}
		config.User = creds.Username
		config.Auth = []ssh.AuthMethod{ssh.PublicKeys(signer)}
	} else {
		// 密码认证
		config.User = creds.Username
		config.Auth = []ssh.AuthMethod{ssh.Password(creds.Password)}
	}
	
	// 直接使用传入的Context，它已经包含了正确的超时设置
	target := fmt.Sprintf("%s:%s", info.Host, info.Ports)
	
	// 使用Context控制超时
	type sshResult struct {
		client *ssh.Client
		err    error
	}
	
	resultChan := make(chan sshResult, 1)
	
	go func() {
		client, err := ssh.Dial("tcp", target, config)
		resultChan <- sshResult{client: client, err: err}
	}()
	
	// 等待结果或超时
	select {
	case result := <-resultChan:
		if result.err != nil {
			return nil, fmt.Errorf("SSH连接失败: %v", result.err)
		}
		return result.client, nil
	case <-ctx.Done():
		return nil, fmt.Errorf("SSH连接超时: %v", ctx.Err())
	}
}

// executeCommand 执行SSH命令
func (e *SSHExploiter) executeCommand(client *ssh.Client, command string) (string, error) {
	session, err := client.NewSession()
	if err != nil {
		return "", err
	}
	defer session.Close()
	
	output, err := session.CombinedOutput(command)
	if err != nil {
		return "", err
	}
	
	return string(output), nil
}