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Fields reference

The Cloudflare Rules language supports a range of field types:

​​ Standard fields

Most standard fields use the same naming conventions as Wireshark display fields. However, there are some subtle differences between Cloudflare and Wireshark:

  • Wireshark supports CIDR (Classless Inter-Domain Routing) notation for expressing IP address ranges in equality comparisons (ip.src == 1.2.3.0/24, for example). Cloudflare does not.

    To evaluate a range of addresses using CIDR notation, use the in comparison operator as in this example: ip.src in {1.2.3.0/24 4.5.6.0/24}.

  • In Wireshark, ssl is a protocol field containing hundreds of other fields of various types that are available for comparison in multiple ways. However, in the Rules language ssl is a single Boolean field that indicates whether the connection from the client to Cloudflare is encrypted.

  • The Cloudflare Rules language does not support the slice operator.

The Cloudflare Rules language supports these standard fields:

FieldDescription
http.host
String

Represents the host name used in the full request URI.

Example value:
www.example.org

http.referer
String

Represents the HTTP Referer request header, which contains the address of the web page that linked to the currently requested page.

Example value:
Referer: htt­ps://developer.example.org/en-US/docs/Web/JavaScript

http.request.full_uri
String

Represents the full URI as received by the web server (does not include #fragment, which is not sent to web servers).

Example value:
htt­ps://www.example.org/articles/index?section=539061&expand=comments

http.request.method
String

Represents the HTTP method, returned as a string of uppercase characters.

Example value:
GET

http.request.cookies
Map<String><Array>

Represents the Cookie HTTP header associated with a request as a Map (associative array).

The cookie values are not pre-processed and retain the original case used in the request.

Decoding: The cookie names are URL decoded. If two cookies have the same name after decoding, their value arrays are merged.

Example:
any(http.request.cookies["app"][*] == "test")

Example value:
{"app": ["test"]}

http.request.timestamp.sec
Integer

Represents the timestamp when Cloudflare received the request, expressed as Unix time in seconds. This value is 10 digits long.

To obtain the timestamp milliseconds, use the http.request.timestamp.msec field.

Example value:
1484063137

When validating HMAC tokens in an expression, pass this field as the currentTimestamp argument to the is_timed_hmac_valid_v0() validation function.

http.request.timestamp.msec
Integer

Represents the millisecond when Cloudflare received the request, between 0 and 999.

To obtain the complete timestamp, use both http.request.timestamp.sec and http.request.timestamp.msec fields.

Example value:
857

http.request.uri
String

Represents the URI path and query string of the request.

Example value:
/articles/index?section=539061&expand=comments

http.request.uri.path
String

Represents the URI path of the request.

Example value:
/articles/index

http.request.uri.query
String

Represents the entire query string, without the ? delimiter.

Example value:
section=539061&expand=comments

http.user_agent
String

Represents the HTTP user agent, a request header that contains a characteristic string to allow identification of the client operating system and web browser.

Example value:
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36

http.request.version
String

Represents the version of the HTTP protocol used. Use this field when you require different checks for different versions.

Example Values:

  • HTTP/1.1
  • HTTP/3
http.x_forwarded_for
String

Represents the full X-Forwarded-For HTTP header.

Example value:
203.0.113.195, 70.41.3.18

ip.src
IP address

Represents the client TCP IP address, which may be adjusted to reflect the actual address of the client by using, for example, HTTP headers such as X-Forwarded-For or X-Real-IP.

Example value:
93.184.216.34

ip.src.lat
String

Represents the latitude associated with the client IP address.

Example value:
37.78044

ip.src.lon
String

Represents the longitude associated with the client IP address.

Example value:
-122.39055

ip.src.city
String

Represents the city associated with the client IP address.

Example value:
San Francisco

ip.src.postal_code
String

Represents the postal code associated with the incoming request.

Example value:
78701

ip.src.metro_code
String

Represents the metro code or Designated Market Area (DMA) code associated with the incoming request.

Example value:
635

ip.geoip.asnum
Number

Represents the 16- or 32-bit integer representing the Autonomous System (AS) number associated with client IP address.

ip.geoip.continent
String
Represents the continent code associated with client IP address:
  • AF – Africa
  • AN – Antarctica
  • AS – Asia
  • EU – Europe
  • NA – North America
  • OC – Oceania
  • SA – South America
  • T1 – Tor network
ip.geoip.country
String

Represents the 2-letter country code in ISO 3166-1 Alpha 2 format.

Example value:
GB

For more information on the ISO 3166-1 Alpha 2 format, refer to ISO 3166-1 Alpha 2 on Wikipedia.

ip.geoip.subdivision_1_iso_code
String

Represents the ISO 3166-2 code for the first level region associated with the IP address. When the actual value is not available, this field contains an empty string.

Example value:
GB-ENG

For more information on the ISO 3166-2 standard and the available regions, refer to ISO 3166-2 on Wikipedia.

ip.geoip.subdivision_2_iso_code
String

Represents the ISO 3166-2 code for the second level region associated with the IP address. When the actual value is not available, this field contains an empty string.

Example value:
GB-SWK

For more information on the ISO 3166-2 standard and the available regions, refer to ISO 3166-2 on Wikipedia.

ip.geoip.is_in_european_union
Boolean

Returns true when the request originates from an EU country.

raw.http.request.full_uri
String

Similar to the http.request.full_uri non-raw field. Represents the full URI as received by the web server without the URI fragment (if any) and without any transformation.

Note: This raw field may include some basic normalization done by Cloudflare's HTTP server. However, this can change in the future.

raw.http.request.uri
String

Similar to the http.request.uri non-raw field. Represents the URI path and query string of the request without any transformation.

Note: This raw field may include some basic normalization done by Cloudflare's HTTP server. However, this can change in the future.

raw.http.request.uri.path
String

Similar to the http.request.uri.path non-raw field. Represents the URI path of the request without any transformation.

Note: This raw field may include some basic normalization done by Cloudflare's HTTP server. However, this can change in the future.

raw.http.request.uri.query
String

Similar to the http.request.uri.query non-raw field. Represents the entire query string without the ? delimiter and without any transformation.

Note: This raw field may include some basic normalization done by Cloudflare's HTTP server. However, this can change in the future.

ssl
Boolean

Returnstrue when the HTTP connection to the client is encrypted.

​​ Dynamic fields

Dynamic fields represent computed or derived values, typically related to threat intelligence about an HTTP request.

The Cloudflare Rules language supports these dynamic fields:

Field NameDescription

cf.bot_management.verified_bot
Boolean

When true, this field indicates the request originated from a known good bot or crawler. Provides the same information as cf.client.bot.

cf.bot_management.score
Number

Represents the likelihood that a request originates from a bot using a score from 1–99.

A low score indicates that the request comes from a bot or an automated agent. A high score indicates that a human issued the request.

cf.bot_management.ja3_hash
String

Provides an SSL/TLS fingerprint to help you identify potential bot requests.

For more details, refer to JA3 Fingerprints.

cf.client.bot
Boolean

When true, this field indicates the request originated from a known good bot or crawler. Provides the same information as cf.bot_management.verified_bot.

cf.edge.server_ip
IP Address

Represents the edge IP address to which the HTTP request has resolved to.

This field is only meaningful for BYOIP customers.

cf.edge.server_port
Number

Represents the port number at which Cloudflare's network received the request.

Use this field to filter traffic on a specific port. The value is a port number in the range 1–65535.

cf.hostname.metadata
String

Returns the string representation of the per-hostname custom metadata JSON object set by SSL for SaaS customers.

cf.random_seed
Bytes

Returns per-request random bytes that you can use in the uuidv4() function.

cf.threat_score
Number

Represents a Cloudflare threat score from 0–100, where 0 indicates low risk. Values above 10 may represent spammers or bots, and values above 40 identify bad actors on the Internet.

It is rare to see values above 60. A common recommendation is to challenge requests with a score above 10 and to block those above 50.

cf.tls_client_auth.cert_revoked
Boolean

Returns true when a request presents a valid but revoked client certificate.

When true, the cf.tls_client_auth.cert_verified field is also true.

cf.tls_client_auth.cert_verified
Boolean

Returns true when a request presents a valid client certificate.

Also returns true when a request includes a valid certificate that was revoked (see cf.tls_client_auth.cert_revoked).

cf.worker.upstream_zone
String

Identifies whether a request comes from a worker or not.

When a request comes from a worker, this field will hold the name of the zone for that worker. Otherwise cf.worker.upstream_zone is empty.

js_score

Customers should not use js_score when creating Bot Management firewall rules because it will always be blank.

​​ Magic Firewall Fields

Field NameDescription

cf.colo.name
String

The data center that is handling this traffic.
Example value: sfo06

cf.colo.region
String

Region of the data center that is handling this traffic.
Example value: WNAM

icmp
String

The raw ICMP packet as a list of bytes. It should be used in conjunction with the bit_slice function when other structured fields are lacking.

icmp.type
Number

The ICMP type. Only applies to ICMP packets.
Example value: 8

icmp.code
Number

The ICMP code. Only applies to ICMP packets.
Example value: 2

ip
String

The raw IP packet as a list of bytes. It should be used in conjunction with the bit_slice function when other structured fields are lacking.

ip.dst
IP Address

The destination address as specified in the IP packet.
Example value: 192.0.2.2

ip.dst.country
String

Represents the 2-letter country code associated with the server IP address in ISO 3166-1 Alpha 2 format.
Example value: GB

For more information on the ISO 3166-1 Alpha 2 format, refer to ISO 3166-1 Alpha 2 on Wikipedia.

ip.geoip.country
String

Represents the 2-letter country code associated with the client IP address in ISO 3166-1 Alpha 2 format.
Example value: GB

For more information on the ISO 3166-1 Alpha 2 format, refer to ISO 3166-1 Alpha 2 on Wikipedia.

ip.hdr_len
Number

The length of the IPv4 header in bytes.
Example value: 5

ip.len
Number

The length of the packet including the header.
Example value: 60

ip.opt.type
Number

The first byte of IP options field, if the options field is set.
Example value: 25

ip.proto
String

The transport layer for the packet, if it can be determined.
Example values: icmp, tcp

ip.src
IP Address

The source address of the IP Packet.

ip.src.country
String

Represents the 2-letter country code associated with the client IP address in ISO 3166-1 Alpha 2 format.
Example value: GB

For more information on the ISO 3166-1 Alpha 2 format, refer to ISO 3166-1 Alpha 2 on Wikipedia.

ip.ttl
Number

The time-to-live of the IP Packet.
Example values: 54

tcp
String

The raw TCP packet as a list of bytes. It should be used in conjunction with the bit_slice function when other structured fields are lacking.

tcp.flags
Number

The numeric value of the TCP flags byte.

tcp.flags.ack
Boolean

TCP acknowledgment flag.

tcp.flags.cwr
Boolean

TCP congestion window reduced flag.

tcp.flags.ecn
Boolean

TCP ECN-Echo flag.

tcp.flags.fin
Boolean

TCP flag indicating this is the last packet from sender.

tcp.flags.push
Boolean

TCP push flag.

tcp.flags.reset
Boolean

TCP reset flag.

tcp.flags.syn
Boolean

TCP synchronize flag.

tcp.flags.urg
Boolean

TCP urgent flag.

tcp.srcport
Number

Source port number of the IP packet. Only applies to TCP packets.

tcp.dstport
Number

Destination port number of the IP packet. Only applies to TCP packets.

udp
String

The raw UDP packet as a list of bytes. It should be used in conjunction with the bit_slice function when other structured fields are lacking.

udp.dstport
Number

Destination port number of the IP packet. Only applies to UDP packets.

udp.srcport
Number

Source port number of the IP packet. Only applies to UDP packets.

​​ URI argument and value fields

The Cloudflare Rules language includes URI argument and value fields associated with HTTP requests. Many of these fields return arrays containing the respective values.

The Cloudflare Rules language supports these URI argument and value fields:

Field NameDescription
http.request.uri.args
Map<String><Array>

Represents the HTTP URI arguments associated with a request as a Map (associative array).

When an argument repeats, then the array contains multiple items in the order they appear in the request.

The values are not pre-processed and retain the original case used in the request.

Decoding: no decoding performed
Non-ASCII: preserved

Example:
any(http.request.uri.args["search"][*] == "red+apples")

Example value:
{"search": ["red+apples"]}

http.request.uri.args.names
Array<String>

Represents the names of the arguments in the HTTP URI query string. The names are not pre-processed and retain the original case used in the request.

When a name repeats, the array contains multiple items in the order that they appear in the request.

Decoding: no decoding performed
Non-ASCII: preserved

Example:
any(http.request.uri.args.names[*] == "search")

Example value:
["search"]

http.request.uri.args.values
Array<String>

Represents the values of arguments in the HTTP URI query string. The values are not pre-processed and retain the original case used in the request. They are in the same order as in the request.

Duplicated values are listed multiple times.

Decoding: no decoding performed
Non-ASCII: preserved

Example:
any(http.request.uri.args.values[*] == "red+apples")

Example value:
["red+apples"]

raw.http.request.uri.args
Map<String><Array>

Contains the same field values as http.request.uri.args.

raw.http.request.uri.args.names
Array<String>

Contains the same field values as http.request.uri.args.names.

raw.http.request.uri.args.values
Array<String>

Contains the same field values as http.request.uri.args.values.

​​ HTTP request header fields

The Rules language includes fields that represent properties of HTTP request headers. Many of these return arrays containing the respective values.

The Cloudflare Rules language supports these HTTP header fields:

Field NameDescription
http.request.headers
Map<String><Array>

Represents HTTP request headers as a Map (or associative array).

The keys of the associative array are the names of HTTP request headers converted to lowercase.

When there are repeating headers, the array includes them in the order they appear in the request.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

Example:
any(http.request.headers["content-type"][*] == "application/json")

Example value:
{"content-type": ["application/json"]}

http.request.headers.names
Array<String>

Represents the names of the headers in the HTTP request.

The names are not pre-processed and retain the original case used in the request.

Note: In HTTP/2 the names of HTTP headers are always in lowercase. Recent versions of the curl tool enable HTTP/2 by default for HTTPS connections.

The order of header names is not guaranteed but will match http.request.headers.values.

Duplicate headers are listed multiple times.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

Example:
any(http.request.headers.names[*] == "content-type")

Example value: ["content-type"]

http.request.headers.values
Array<String>

Represents the values of the headers in the HTTP request.

The values are not pre-processed and retain the original case used in the request.

The order of header values is not guaranteed but will match http.request.headers.names.

Duplicate headers are listed multiple times.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

Example 1:
any(http.request.headers.values[*] == "application/json")

Example value 1:
["application/json"]

Additionally used to match requests according to the specified operator and the length/size entered for the header value.

Example 2:
any(len(http.request.headers.values[*])[*] gt 10)

Example value 2:
["This header value is longer than 10 bytes"]

http.request.headers.truncated
Boolean

Returns true when the HTTP request contains too many headers; otherwise, returns false.

When true, http.request.headers, http.request.headers.names, and http.request.headers.values may not contain all of the headers sent in the HTTP request.

http.request.accepted_languages
Array<String>

Represents the list of language tags provided in the Accept-Language HTTP request header, sorted by weight (;q=<weight>, with a default weight of 1) in descending order.

If the HTTP header is not present in the request or is empty, http.request.accepted_languages[0] will return a "missing value", which the concat() function will handle as an empty string.

If the HTTP header includes the language tag * it will not be stored in the array.

Example 1:
Request with header Accept-Language: fr-CH, fr;q=0.8, en;q=0.9, de;q=0.7, *;q=0.5. In this case:
http.request.accepted_languages[0] == "fr-CH"
http.request.accepted_languages == ["fr-CH", "en", "fr", "de"]

Example 2:
Request without an Accept-Language HTTP header and a URI of https://www.example.com/my-path. In this case:
concat("/", http.request.accepted_languages[0], http.request.uri.path) == "//my-path".

Note: This field is only available in Transform Rules.

​​ HTTP request body fields

The Rules language includes fields that represent properties of an HTTP request body. Many of these return arrays containing the respective values.

The Cloudflare Rules language supports these HTTP body fields:

Field NameDescription
http.request.body.raw
String

Represents the unaltered HTTP request body.

When the value of http.request.body.truncated is true, the return value may be truncated.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

http.request.body.truncated
Boolean

Indicates whether the HTTP request body is truncated.

When true, http.request.body fields may not contain all of the HTTP request body.

http.request.body.form
Map<String><Array>

Represents the HTTP request body of a form as a Map (or associative array). Populated when the Content-Type header is application/x-www-form-urlencoded.

The values are not pre-processed and retain the original case used in the request.

When a field repeats, then the array contains multiple items in the order they are in the request.

The return value may be truncated if http.request.body.truncated is true.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

Example:
any(http.request.body.form["username"][*] == "admin")

Example value:
{username": ["admin"]}

http.request.body.form.names
Array<String>

Represents the names of the form fields in an HTTP request where the content type is application/x-www-form-urlencoded.

The names are not pre-processed and retain the original case used in the request. They are listed in the same order as in the request.

Duplicate names are listed multiple times.

The return value may be truncated if http.request.body.truncated is true.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

Example:
any(http.request.body.form.names[*] == "username")

Example value:
["username"]

http.request.body.form.values
Array<String>

Represents the values of the form fields in an HTTP request where the content type is application/x-www-form-urlencoded.

The values are not pre-processed and retain the original case used in the request. They are listed in the same order as in the request.

Duplicated values are listed multiple times.

The return value may be truncated if http.request.body.truncated is true.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

Example:
any(http.request.body.form.values[*] == "admin")

Example value:
["admin"]

http.request.body.mime
String

The MIME type of the request detected from the request body.

Supports the most common MIME types of the following general categories: video, audio, image, application, text.

Example:
image/jpeg

This field is available on all Cloudflare plans.

​​ HTTP response fields

The Rules language includes fields that represent properties of HTTP response returned by the origin or by a Worker script.

The Cloudflare Rules language supports these HTTP response fields:

Field NameDescription
http.response.code
Integer

Represents the HTTP status code returned by the origin.

Example value:
403

http.response.headers
Map<String><Array>

Represents HTTP response headers as a Map (or associative array).

When there are repeating headers, the array includes them in the order they appear in the response. The keys convert to lowercase.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

Example:
any(http.response.headers["server"][*] == "nginx")

Example value:
{"server": ["nginx"]}

http.response.headers.names
Array<String>

Represents the names of the headers in the HTTP response. The names are not pre-processed and retain the original case used in the response.

The order of header names is not guaranteed but will match http.response.headers.values.

Duplicate headers are listed multiple times.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

Example:
any(http.response.headers.names[*] == "content-type")

Example value: ["content-type"]

http.response.headers.values
Array<String>

Represents the values of the headers in the HTTP response.

The values are not pre-processed and retain the original case used in the response.

The order of header values is not guaranteed but will match http.response.headers.names.

Duplicate headers are listed multiple times.

Decoding: no decoding performed
Whitespace: preserved
Non-ASCII: preserved

Example 1:
any(http.response.headers.values[*] == "application/json")

Example value 1:
["application/json"]

Additionally used to match responses according to the specified operator and the length/size entered for the header value.

Example 2:
any(len(http.response.headers.values[*])[*] gt 10)

Example value 2:
["This header value is longer than 10 bytes"]

cf.response.1xxx_code
Integer

Contains the specific code for 1xxx Cloudflare errors. Use this field to differentiate between 1xxx errors associated with the same HTTP status code. The default value is 0. For a list of 1xxx errors, refer to Troubleshooting Cloudflare 1XXX errors.

Example value:
1020

Note: This field is only available in HTTP response header modifications and custom error responses.

cf.response.error_type
String

Contains a string with the type of error in the response being returned. The default value is an empty string ("").

The available values are the following:

  • managed_challenge
  • iuam_basic
  • legacy_challenge
  • ip_block
  • waf_block
  • 5xx
  • 1xxx
  • always_online
  • country_challenge
  • ratelimit

You can use this field to customize the response for a specific type of error (for example, all 1xxx errors or all WAF block actions).

Note: This field is only available in HTTP response header modifications and custom error responses.


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