graph TB
    Client["Claude Desktop<br/>(or any MCP client)"]
    Server["SSH MCP Server"]
    MCP["MCP SDK<br/>(stdio)"]
    Router["Tool Router<br/>(index.ts)"]
    Security["Security Module<br/>- Dangerous cmd detection<br/>- Audit logging"]
    SSH["SSH Client (ssh2)"]
    Exec["exec()<br/>- Commands<br/>- cat (read)"]
    Interactive["exec() + PTY<br/>- Interactive commands<br/>- Auto prompt response"]
    Shell["shell() + PTY<br/>- Persistent sessions<br/>- REPLs / multi-step"]
    SFTP["SFTP (lazy init)<br/>- upload / download<br/>- ls / write / readdir"]
    Remote["Remote Server<br/>(Linux/Unix)"]

    Client -->|"stdio (JSON-RPC)"| Server
    Server --- MCP
    MCP --> Router
    Router --> Security
    Router --> SSH
    SSH --- Exec
    SSH --- Interactive
    SSH --- Shell
    SSH --- SFTP
    SSH -->|"SSH (TCP :22)"| Remote

flowchart TD
    Start([Start]) --> ListProfiles["ssh_list_profiles<br/>View available profiles"]
    ListProfiles --> Connect["ssh_connect<br/>(profile name)"]
    Connect -->|Password not found| Error["Error: env var<br/>SSH_PASSWORD_NAME missing"]
    Connect -->|OK| Active["Active Connection<br/>(1 profile at a time)"]

    Active --> ExecBranch["ssh_exec<br/>(command)"]
    Active --> InteractiveBranch["ssh_exec_interactive<br/>(command + auto-responses)"]
    Active --> ShellBranch["Shell Sessions<br/>start / send / read / close"]
    Active --> SFTPBranch["SFTP operations<br/>upload / download<br/>ls / read / write"]
    Active --> StatusBranch["ssh_status<br/>ssh_disconnect"]

    ExecBranch --> DangerCheck{"Dangerous<br/>command?<br/>(regex)"}
    InteractiveBranch --> DangerCheck
    DangerCheck -->|No| Execute["Execute command"]
    DangerCheck -->|Yes| ConfirmCheck{"confirm:<br/>true?"}
    ConfirmCheck -->|Yes| Execute
    ConfirmCheck -->|No| Warning["WARNING<br/>(not executed)"]

    ShellBranch -->|"send (raw:false)"| DangerCheck
    ShellBranch -->|"send (raw:true)"| Execute

    Execute --> Audit["audit.log"]
    SFTPBranch --> Audit
    Warning --> Audit

flowchart LR
    Input["Command received"] --> Check["isDangerousCommand()<br/>(16 regex patterns)"]
    Check -->|Safe| Exec["Execute command"]
    Check -->|Dangerous| Confirm{"confirm: true?"}
    Confirm -->|Yes| Exec
    Confirm -->|No| Warn["WARNING returned<br/>(command NOT executed)"]
    Exec --> Log["audit.log"]
    Warn --> Log

    subgraph Detected Patterns
        P1["rm -rf /"]
        P2["mkfs.*"]
        P3["dd if="]
        P4["reboot / shutdown / halt"]
        P5["chmod 777 / chown -R"]
        P6["fork bomb"]
        P7["systemctl stop/disable"]
        P8["killall / iptables -F"]
    end

s01_ssh_mcp/
├── src/
│   ├── index.ts       # SSHMCPServer class — tool router, SSH logic, interactive/shell handlers
│   ├── tools.ts       # MCP tool definitions (17 tools, JSON schemas)
│   ├── profiles.ts    # Profile loading + password injection from env
│   ├── security.ts    # Dangerous command detection + AuditLogger
│   └── types.ts       # Interfaces: SSHProfile, AuditEntry, PromptResponse, ShellSession, CommandRecord, ReverseInfo
├── dist/              # Compiled output (generated by tsc)
├── profiles.json      # SSH server configuration
├── .env               # Passwords (not versioned)
├── audit.log          # Audit log (generated at runtime)
├── package.json
└── tsconfig.json

{
  "production": {
    "host": "192.168.1.100",
    "port": 22,
    "username": "deploy"
  },
  "staging": {
    "host": "192.168.1.101",
    "port": 22,
    "username": "deploy"
  }
}

SSH_PASSWORD_PRODUCTION=your_password
SSH_PASSWORD_STAGING=your_password

npm install
npm run build
npm start

{
  "mcpServers": {
    "ssh": {
      "command": "npx",
      "args": ["-y", "s01-ssh-mcp"],
      "env": {
        "SSH_PASSWORD_PRODUCTION": "your_password",
        "SSH_PASSWORD_STAGING": "your_password"
      }
    }
  }
}

{
  "mcpServers": {
    "ssh": {
      "command": "node",
      "args": ["/path/to/s01_ssh_mcp/dist/index.js"],
      "env": {
        "SSH_PASSWORD_PRODUCTION": "your_password",
        "SSH_PASSWORD_STAGING": "your_password"
      }
    }
  }
}

[timestamp] [profile] [tool] [parameters] [RESULT: ok|error]

[2026-03-04T10:30:00.000Z] [production] [ssh_exec] [ls -la /var/log] [RESULT: ok]
[2026-03-04T10:31:00.000Z] [production] [ssh_upload] [./app.tar.gz -> /tmp/app.tar.gz] [RESULT: ok]