MCP SSH Server

Instructions

Implementation Reference

• src/index.ts:658-776 (handler)

  The handler function that executes the ssh_copy_file tool. It parses input with CopyFileSchema, handles four copy scenarios (local-local, local-remote, remote-local, remote-remote) using fs.copyFile, NodeSSH.putFile/getFile, creates directories if needed, and uses temp file for remote-remote transfers.

  private async handleSSHCopyFile(args: unknown) {
    const params = CopyFileSchema.parse(args);
    
    try {
      // Handle different copy scenarios
      if (params.sourceConnectionId === 'local' && params.targetConnectionId === 'local') {
        // Local to local copy
        await fs.copyFile(params.sourcePath, params.targetPath);
        return {
          content: [
            {
              type: 'text',
              text: `Successfully copied ${params.sourcePath} to ${params.targetPath} (local to local)`,
            },
          ],
        };
      } else if (params.sourceConnectionId === 'local') {
        // Local to remote
        const targetSSH = connectionPool.get(params.targetConnectionId);
        if (!targetSSH) {
          throw new McpError(
            ErrorCode.InvalidParams,
            `Target connection ID '${params.targetConnectionId}' not found`
          );
        }
  
        if (params.createDirectories) {
          const targetDir = path.dirname(params.targetPath);
          await targetSSH.execCommand(`mkdir -p "${targetDir}"`);
        }
  
        await targetSSH.putFile(params.sourcePath, params.targetPath);
        return {
          content: [
            {
              type: 'text',
              text: `Successfully copied ${params.sourcePath} to ${params.targetConnectionId}:${params.targetPath}`,
            },
          ],
        };
      } else if (params.targetConnectionId === 'local') {
        // Remote to local
        const sourceSSH = connectionPool.get(params.sourceConnectionId);
        if (!sourceSSH) {
          throw new McpError(
            ErrorCode.InvalidParams,
            `Source connection ID '${params.sourceConnectionId}' not found`
          );
        }
  
        if (params.createDirectories) {
          const targetDir = path.dirname(params.targetPath);
          await fs.mkdir(targetDir, { recursive: true });
        }
  
        await sourceSSH.getFile(params.targetPath, params.sourcePath);
        return {
          content: [
            {
              type: 'text',
              text: `Successfully copied ${params.sourceConnectionId}:${params.sourcePath} to ${params.targetPath}`,
            },
          ],
        };
      } else {
        // Remote to remote
        const sourceSSH = connectionPool.get(params.sourceConnectionId);
        const targetSSH = connectionPool.get(params.targetConnectionId);
        
        if (!sourceSSH) {
          throw new McpError(
            ErrorCode.InvalidParams,
            `Source connection ID '${params.sourceConnectionId}' not found`
          );
        }
        if (!targetSSH) {
          throw new McpError(
            ErrorCode.InvalidParams,
            `Target connection ID '${params.targetConnectionId}' not found`
          );
        }
  
        // Use a temporary local file for remote-to-remote transfer
        const tempFile = `/tmp/mcp-ssh-temp-${Date.now()}-${Math.random().toString(36).substr(2, 9)}`;
        
        try {
          await sourceSSH.getFile(tempFile, params.sourcePath);
          
          if (params.createDirectories) {
            const targetDir = path.dirname(params.targetPath);
            await targetSSH.execCommand(`mkdir -p "${targetDir}"`);
          }
          
          await targetSSH.putFile(tempFile, params.targetPath);
          await fs.unlink(tempFile); // Clean up temp file
          
          return {
            content: [
              {
                type: 'text',
                text: `Successfully copied ${params.sourceConnectionId}:${params.sourcePath} to ${params.targetConnectionId}:${params.targetPath}`,
              },
            ],
          };
        } catch (error) {
          // Clean up temp file on error
          try {
            await fs.unlink(tempFile);
          } catch {}
          throw error;
        }
      }
    } catch (error) {
      throw new McpError(
        ErrorCode.InternalError,
        `File copy failed: ${error instanceof Error ? error.message : String(error)}`
      );
    }
  }

• src/index.ts:80-86 (schema)

  Zod schema defining and validating the input parameters for the ssh_copy_file tool.

  const CopyFileSchema = z.object({
    sourceConnectionId: z.string().describe('Source SSH connection ID (use "local" for local files)'),
    sourcePath: z.string().describe('Source file path'),
    targetConnectionId: z.string().describe('Target SSH connection ID (use "local" for local files)'),
    targetPath: z.string().describe('Target file path'),
    createDirectories: z.boolean().default(true).describe('Create target directories if they don\'t exist')
  });

• src/index.ts:279-293 (registration)

  Tool registration in the ListToolsRequestSchema response, defining name, description, and input schema for ssh_copy_file.

  {
    name: 'ssh_copy_file',
    description: 'Copy files between local and remote servers or between remote servers',
    inputSchema: {
      type: 'object',
      properties: {
        sourceConnectionId: { type: 'string', description: 'Source SSH connection ID (use "local" for local files)' },
        sourcePath: { type: 'string', description: 'Source file path' },
        targetConnectionId: { type: 'string', description: 'Target SSH connection ID (use "local" for local files)' },
        targetPath: { type: 'string', description: 'Target file path' },
        createDirectories: { type: 'boolean', default: true, description: 'Create target directories if they don\'t exist' }
      },
      required: ['sourceConnectionId', 'sourcePath', 'targetConnectionId', 'targetPath']
    },
  },

• src/index.ts:491-492 (registration)

  Dispatch case in CallToolRequestSchema handler that routes ssh_copy_file calls to the handleSSHCopyFile method.

  case 'ssh_copy_file':
    return await this.handleSSHCopyFile(args);