# jpr5/ngrep

ngrep is like GNU grep applied to the network layer. It's a PCAP-based tool that allows you to specify an extended regular or hexadecimal expression to match against data payloads of packets. It understands many kinds of protocols, including IPv4/6, TCP, UDP, ICMPv4/6, IGMP and Raw, across a wide variety of interface types, and understands BPF filter logic in the same fashion as more common packet sniffing tools, such as tcpdump and snoop.

Repository: https://github.com/jpr5/ngrep
Canonical: https://ross.abutalabs.com/products/ngrep
Homepage: https://github.com/jpr5/ngrep
Language: C
License: NOASSERTION
License Family: other
Topics: sniffer, grepping
Last push: 2026-02-08T03:34:33+00:00

## Health v2 (maintenance only)
Score: 74/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 66, release rhythm 69, longevity 100
- inputs: {"age_days": 6090, "days_push": 206, "days_rel": 206, "gap_med": 8, "n_releases_24m": 4}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1020, forks 106 (observed 2026-08-28T04:03:15.555337+00:00)

## What it is
ngrep is a PCAP-based command-line tool that applies GNU grep-style regular or hexadecimal expression matching to network packet payloads. It understands IPv4/6, TCP, UDP, ICMPv4/6, IGMP and Raw protocols and supports BPF filter logic like tcpdump.

## Use cases
- grep network traffic for a pattern
- debug plaintext protocol interactions like HTTP, DNS, SIP
- search pcap dump files for specific data
- analyze anomalous network communications from malware
- sniff packets matching a BPF filter
- inspect HTTP requests on port 80

## When to choose
- you need to search live traffic or pcap files for payload patterns with regex
- you want tcpdump-style BPF filtering combined with grep-style matching
- you're debugging plaintext protocols like HTTP, IMAP, or DNS

## When to avoid
- you need deep protocol dissection or GUI analysis (use Wireshark)
- traffic is encrypted and you need to inspect decrypted content
- you need long-term traffic monitoring or alerting rather than ad-hoc matching

## Facets
- artifact type: cli-tool
- maturity: active
- function: search-engine, networking, security, developer-tools, cli
- domain: networking, security, developer-tools
- platform: windows, cli, cross-platform
- tags: packet-sniffer, pcap, grep, network-debugging, bpf-filter, tcpdump, traffic-analysis, command-line, linux, macos, docker

## Member repositories
- jpr5/ngrep (main) score 74

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:15.555337+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T07:09:17.867897+00:00, confidence not recorded.
  - readme: https://github.com/jpr5/ngrep (fetched 2026-08-28T04:03:15.555337+00:00, sha 7bfb4c8bf3dc)
  - homepage: https://github.com/jpr5/ngrep (fetched 2026-08-29T13:09:16.605524+00:00, sha f124a8d9369e)
- Data as of 2026-08-30T08:39:29.467469+00:00.