ajarbot/mcp_servers/mcp_ssh.py

"""SSH MCP Server for remote command execution via SSH.

Provides SSH access to remote hosts for the bot.
"""

import asyncio
from typing import Any, Dict

try:
    import paramiko
    PARAMIKO_AVAILABLE = True
except ImportError:
    PARAMIKO_AVAILABLE = False

from claude_agent_sdk import tool, create_sdk_mcp_server


@tool(
    name="ssh_execute",
    description="Execute a command on a remote host via SSH. Returns stdout, stderr, and exit code.",
    input_schema={
        "host": str,
        "username": str,
        "password": str,
        "key_filename": str,
        "command": str,
        "port": int,
    },
)
async def ssh_execute(args: Dict[str, Any]) -> Dict[str, Any]:
    """Execute a command on a remote host via SSH."""
    if not PARAMIKO_AVAILABLE:
        return {
            "content": [{"type": "text", "text": "Error: paramiko not installed. Run: pip install paramiko"}],
            "isError": True
        }

    host = args.get("host")
    username = args.get("username")
    password = args.get("password")
    key_filename = args.get("key_filename")
    command = args.get("command")
    port = args.get("port", 22)

    if not all([host, username, command]):
        return {
            "content": [{"type": "text", "text": "Error: Missing required parameters: host, username, command"}],
            "isError": True
        }

    if not password and not key_filename:
        return {
            "content": [{"type": "text", "text": "Error: Must provide either password or key_filename for authentication"}],
            "isError": True
        }

    try:
        # Run SSH command in thread pool to avoid blocking
        loop = asyncio.get_event_loop()
        result = await loop.run_in_executor(
            None,
            _execute_ssh_sync,
            host,
            port,
            username,
            password,
            key_filename,
            command
        )

        # Format result as MCP-compliant text content
        if result["success"]:
            output_parts = [f"SSH command executed on {result['host']} (auth: {result['auth_method']})"]
            output_parts.append(f"Exit code: {result['exit_code']}")

            if result["stdout"]:
                stdout = result["stdout"]
                if len(stdout) > 5000:
                    stdout = stdout[:5000] + "\n... (stdout truncated)"
                output_parts.append(f"\nSTDOUT:\n{stdout}")

            if result["stderr"]:
                stderr = result["stderr"]
                if len(stderr) > 5000:
                    stderr = stderr[:5000] + "\n... (stderr truncated)"
                output_parts.append(f"\nSTDERR:\n{stderr}")

            if not result["stdout"] and not result["stderr"]:
                output_parts.append("\n(no output)")

            return {
                "content": [{"type": "text", "text": "\n".join(output_parts)}],
                "isError": result["exit_code"] != 0
            }
        else:
            return {
                "content": [{"type": "text", "text": f"SSH Error: {result['error']}"}],
                "isError": True
            }

    except Exception as e:
        return {
            "content": [{"type": "text", "text": f"SSH execution failed: {str(e)}"}],
            "isError": True
        }


def _execute_ssh_sync(host: str, port: int, username: str, password: str, key_filename: str, command: str) -> Dict[str, Any]:
    """Synchronous SSH execution (runs in thread pool)."""
    client = paramiko.SSHClient()
    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())

    try:
        # Build connection parameters
        connect_kwargs = {
            "hostname": host,
            "port": port,
            "username": username,
            "timeout": 30,
        }

        # Use key-based auth if key_filename provided, otherwise use password
        if key_filename:
            connect_kwargs["key_filename"] = key_filename
        else:
            connect_kwargs["password"] = password

        client.connect(**connect_kwargs)

        stdin, stdout, stderr = client.exec_command(command)

        stdout_text = stdout.read().decode('utf-8')
        stderr_text = stderr.read().decode('utf-8')
        exit_code = stdout.channel.recv_exit_status()

        return {
            "success": True,
            "stdout": stdout_text,
            "stderr": stderr_text,
            "exit_code": exit_code,
            "host": host,
            "auth_method": "key" if key_filename else "password",
        }
    finally:
        client.close()


@tool(
    name="ssh_file_upload",
    description="Upload a file to a remote host via SFTP. Returns success status and file paths.",
    input_schema={
        "host": str,
        "username": str,
        "password": str,
        "key_filename": str,
        "local_path": str,
        "remote_path": str,
        "port": int,
    },
)
async def ssh_file_upload(args: Dict[str, Any]) -> Dict[str, Any]:
    """Upload a file to a remote host via SFTP."""
    if not PARAMIKO_AVAILABLE:
        return {
            "content": [{"type": "text", "text": "Error: paramiko not installed. Run: pip install paramiko"}],
            "isError": True
        }

    host = args.get("host")
    username = args.get("username")
    password = args.get("password")
    key_filename = args.get("key_filename")
    local_path = args.get("local_path")
    remote_path = args.get("remote_path")
    port = args.get("port", 22)

    if not all([host, username, local_path, remote_path]):
        return {
            "content": [{"type": "text", "text": "Error: Missing required parameters: host, username, local_path, remote_path"}],
            "isError": True
        }

    if not password and not key_filename:
        return {
            "content": [{"type": "text", "text": "Error: Must provide either password or key_filename for authentication"}],
            "isError": True
        }

    try:
        loop = asyncio.get_event_loop()
        result = await loop.run_in_executor(
            None,
            _upload_file_sync,
            host,
            port,
            username,
            password,
            key_filename,
            local_path,
            remote_path
        )

        # Format result as MCP-compliant text content
        if result["success"]:
            text = (
                f"File uploaded successfully via SFTP\n"
                f"Host: {result['host']}\n"
                f"Auth: {result['auth_method']}\n"
                f"Local: {result['local_path']}\n"
                f"Remote: {result['remote_path']}"
            )
            return {
                "content": [{"type": "text", "text": text}]
            }
        else:
            return {
                "content": [{"type": "text", "text": f"SFTP Error: {result['error']}"}],
                "isError": True
            }

    except Exception as e:
        return {
            "content": [{"type": "text", "text": f"SFTP upload failed: {str(e)}"}],
            "isError": True
        }


def _upload_file_sync(host: str, port: int, username: str, password: str, key_filename: str, local_path: str, remote_path: str) -> Dict[str, Any]:
    """Synchronous SFTP upload (runs in thread pool)."""
    transport = paramiko.Transport((host, port))

    try:
        # Use key-based auth if key_filename provided, otherwise use password
        if key_filename:
            private_key = paramiko.RSAKey.from_private_key_file(key_filename)
            transport.connect(username=username, pkey=private_key)
        else:
            transport.connect(username=username, password=password)

        sftp = paramiko.SFTPClient.from_transport(transport)

        sftp.put(local_path, remote_path)

        return {
            "success": True,
            "local_path": local_path,
            "remote_path": remote_path,
            "host": host,
            "auth_method": "key" if key_filename else "password",
        }
    finally:
        sftp.close() if 'sftp' in locals() else None
        transport.close()


# Create the MCP server
ssh_mcp_server = create_sdk_mcp_server(
    name="ssh",
    version="1.0.0",
    tools=[ssh_execute, ssh_file_upload],
)