smallwebwaf/docs/request-log.md

The request log's fields

The fields of the JSON object smallwebwaf writes for each request. "Request log" in SPEC.md says when a line is written and how the log is sent to a syslog server. A field that does not apply to a request is left out.

Example

{"type":"request","time":"2026-10-03T12:00:00.123Z","instance":"fsn1app1/gitea","client_ip":"203.0.113.9","method":"GET","scheme":"https","host":"app.example","path":"/","query":"","protocol":"HTTP/1.1","status":200,"request_bytes":0,"response_bytes":5120,"referer":"","user_agent":"curl/8.9.1","request_id":"7Q2NHZ4KJ3VXW5YB6R3MEFTD2A","peer_ip":"172.18.0.2","forwarded_for":"203.0.113.9","client_group":"203.0.113.9/32","asn":"AS64496","as_name":"Example Net","country":"DE","request_headers":{"accept":"*/*"},"response_content_type":"text/html; charset=utf-8","upstream_status":200,"action":"forward","counts":{"minute":1,"hour":12,"day":40,"minute_bytes":5120,"hour_bytes":61440,"day_bytes":204800},"duration_total":3.217,"duration_checks":0.041,"duration_upstream_connect":0.052,"duration_upstream_first_byte":2.874,"duration_upstream_total":3.104}

Every line

Every line has:

• type: request (the process's own messages have process);
• the standard web log fields;
• request_id, peer_ip and client_group;
• asn, as_name and country;
• action and duration_total.

Standard web log fields

• time: when the request arrived, RFC 3339 with milliseconds, in UTC;
• instance: SWWAF_INSTANCE_NAME;
• client_ip, method, scheme, host, path, query, protocol;
• status: what the client was sent, 0 if nothing;
• request_bytes and response_bytes: body bytes each way;
• referer and user_agent.

Request detail

• request_id: the X-Request-ID a trusted proxy sent, or a new random one of 26 letters and digits.
• peer_ip: the TCP peer, normally traefik.
• forwarded_for: the X-Forwarded-For header as received.
• client_group: the client as rate limiting counts it, an IPv4 address as a /32 or an IPv6 group.
• asn, as_name and country: the client's, as looked up. Each is empty when:
  • lookups are off;
  • the client is not looked up;
  • the source cannot place the client;
  • GeoJS had not answered by the time the request went on.
• content_type and content_length: the request's own.
• request_headers: the headers listed in SWWAF_LOG_REQUEST_HEADERS, by name in lower case.
• has_authorization and has_cookie: true when the request had those headers. Their values are never logged.
• websocket: true when the app switched the connection to another protocol.

Response detail

• upstream_status: what the app answered. It differs from status when smallwebwaf answered itself.
• response_content_type, cache_control and location: the answer's headers.
• aborted: true when the client went away early.

Decision

• action: what was done:

  • forward: passed to the app;
  • denied: refused for SWWAF_DENY_NETS, or for a reputation source with the action deny;
  • banned: refused under a ban, or for a ban rule, a trap path or a CrowdSec decision, each of which bans the client;
  • country_denied, rate_limited, rule_blocked and waf_blocked: refused by that check;
  • too_large and timed_out: a size or time limit was passed;
  • upstream_error: the app could not be reached, or its answer broke off;
  • admin: answered at one of smallwebwaf's own endpoints.

• would_action: in observe mode, what enforce mode would have done with a request it would have refused. action then names what was done, normally forward.

• limit_percent and limit_percent_setting: the client's percentage of the rate limits and the setting that lowered it, when one did. bytes_percent and bytes_percent_setting do the same for the byte limits.

• counts: the client's totals as rate limiting counts them, this request included. It is left out when rate limiting did not count the request. It holds:

  • minute, hour and day: requests;
  • minute_bytes, hour_bytes and day_bytes: bytes.

  A count can have a fraction (see "Counting method" in SPEC.md).

• limit_hit: the limit broken:

  • minute, hour or day for a rate limit;
  • minute_bytes, hour_bytes or day_bytes for a byte limit;
  • error_burst.

  A request whose bytes broke a limit was passed on whole, so its action stays forward.

• rule_ids: the rule file rules that matched, in order, up to the one that refused.

• waf_score and waf_rule_ids: the Core Rule Set's score and the rules that matched, for a request it inspected.

• reputation: the sources the client is on, in this order:

  • blocklist URLs;
  • the CrowdSec decision list's URL;
  • DNS blocklist zones;
  • abuseipdb.

• offence: limit, for a request that broke a limit.

• ban_expires: when the client's ban ends, for a request that made one or was refused under one: a time, or permanent.

Timings

All in milliseconds:

• duration_total: from the request's headers being read to its log line;
• duration_checks: to the end of the checks, before forwarding;
• duration_waf: the part of that the Core Rule Set took;
• duration_upstream_connect: from the hand-over to the app until there was a connection;
• duration_upstream_first_byte: until the first byte of the answer;
• duration_upstream_total: until the end of the answer.

servewaf's line

smallwebwaf servewaf writes one line for each question, once it has answered it, and one for each request to its own endpoints but a report. A report writes no line. A question's line has the fields above, with these meanings where they differ:

• client_ip: X-Smallwebwaf-Client.
• peer_ip: X-Smallwebwaf-Peer.
• host: the site the visitor asked for.
• protocol: the question's own, HTTP/1.1.
• content_length: X-Smallwebwaf-Content-Length.
• request_id: the id servewaf answers with on allow.
• status: what servewaf answered: 200 for allow, the status of deny, or 0 for close, as the visitor is then sent nothing.
• request_bytes: how much of the question's body the Core Rule Set read.
• response_bytes: the body of servewaf's answer.
• action: forward for allow, and admin for the 404 for a path under /_smallwebwaf/.
• aborted: true when rproxy went away before the answer.
• duration_total: from the question's headers being read to the line.

The line leaves out upstream_status, websocket and the duration_upstream_... fields, since servewaf passes nothing to the app. rproxy holds the visitor's status, the body bytes and the times of the app's answer. The request id joins the two.

The bytes of an allowed request are counted when its report comes, after its line. So counts holds the client's bytes without this request's. A report that breaks a byte limit writes a process message instead of limit_hit on the line: a report's bytes broke a byte limit, with request_id, client_ip, host, limit_hit and ban_expires.