memcached

Documentation

Overview

Package memcached implements fingerprinting for Memcached distributed memory cache servers.

Memcached Wire Protocol Detection

This plugin implements Memcached fingerprinting using the text (ASCII) protocol to ensure compatibility across all Memcached versions from 1.4.x to 1.6.x+.

Detection Strategy:

PHASE 1 - DETECTION (determines if the service is Memcached):
  PRIMARY PATH: version command
    - Send: version\r\n
    - Expected: VERSION <version>\r\n
    - Works on ALL Memcached versions (1.0+ to 1.6.x+)
    - Directly provides version string (100% confidence)

  SECONDARY PATH (FALLBACK): stats command
    - Send: stats\r\n
    - Expected: STAT <key> <value>\r\n ... END\r\n
    - Contains "STAT version <version>" line
    - Works on ALL Memcached versions

PHASE 2 - ENRICHMENT (extracts version information):
  After Memcached is detected, version is already extracted from the detection response.
  No additional enrichment needed (unlike Redis INFO or MongoDB buildInfo).

Memcached Text Protocol:

version Command:

Request:  version\r\n
Response: VERSION <version>\r\n

Example:
  Request:  version\r\n
  Response: VERSION 1.6.22\r\n

stats Command (Fallback):

Request:  stats\r\n
Response: STAT <name> <value>\r\n
          STAT <name> <value>\r\n
          ...
          END\r\n

Example:
  Request:  stats\r\n
  Response: STAT pid 1162\r\n
            STAT uptime 5022\r\n
            STAT version 1.6.22\r\n
            ...
            END\r\n

Error Responses:

• ERROR\r\n - Unknown command (indicates NOT Memcached)
• CLIENT_ERROR <error>\r\n - Invalid command format
• SERVER_ERROR <error>\r\n - Server error

Version Compatibility Matrix:

• Memcached 1.4.x: Text + Binary protocols, UDP enabled
• Memcached 1.5.x: Text + Binary protocols, UDP disabled by default, TLS added
• Memcached 1.6.x: Text + Meta protocols, Binary deprecated, extstore support

Note: The text protocol (including version and stats commands) is supported across all versions and will be maintained indefinitely per Memcached project.

Index

• Constants
• func DetectMemcached(conn net.Conn, timeout time.Duration) (string, bool, error)
• type MEMCACHEDPlugin
  • func (p *MEMCACHEDPlugin) Name() string
  • func (p *MEMCACHEDPlugin) PortPriority(port uint16) bool
  • func (p *MEMCACHEDPlugin) Priority() int
  • func (p *MEMCACHEDPlugin) Run(conn net.Conn, timeout time.Duration, target plugins.Target) (*plugins.Service, error)
  • func (p *MEMCACHEDPlugin) Type() plugins.Protocol

Constants

const DEFAULT_PORT = 11211

Memcached default port

const MEMCACHED = "memcached"

Functions

func DetectMemcached

func DetectMemcached(conn net.Conn, timeout time.Duration) (string, bool, error)

DetectMemcached performs Memcached fingerprinting using the text protocol.

Detection Strategy:

1. DETECTION PHASE: Use version command to detect Memcached and extract version - PRIMARY PATH: Send "version\r\n" command Works on ALL Memcached versions (1.0+ to 1.6.x+) Directly provides version string (100% confidence)
2. FALLBACK: If version command fails, try stats command - Send "stats\r\n" command - Extract version from "STAT version <version>" line

Parameters:

• conn: Network connection to the Memcached server
• timeout: Timeout duration for network operations

Returns:

• string: Version string if detected, empty string otherwise
• bool: true if this appears to be Memcached
• error: Error details if detection failed

Types

type MEMCACHEDPlugin

type MEMCACHEDPlugin struct{}

func (*MEMCACHEDPlugin) Name

func (p *MEMCACHEDPlugin) Name() string

func (*MEMCACHEDPlugin) PortPriority

func (p *MEMCACHEDPlugin) PortPriority(port uint16) bool

func (*MEMCACHEDPlugin) Priority

func (p *MEMCACHEDPlugin) Priority() int

func (*MEMCACHEDPlugin) Run

func (p *MEMCACHEDPlugin) Run(conn net.Conn, timeout time.Duration, target plugins.Target) (*plugins.Service, error)

func (*MEMCACHEDPlugin) Type

func (p *MEMCACHEDPlugin) Type() plugins.Protocol