Class: Otto::Privacy::RedactedFingerprint

Inherits:
Object
  • Object
show all
Defined in:
lib/otto/privacy/redacted_fingerprint.rb

Overview

Immutable privacy-safe request fingerprint (aka CrappyFingerprint)

Contains anonymized information about a request that can be used for logging, analytics, and session tracking without storing personally identifiable information.

Examples:

Create from Rack environment

config = Otto::Privacy::Config.new
fingerprint = RedactedFingerprint.new(env, config)
fingerprint.masked_ip   # => '192.168.1.0'
fingerprint.country     # => 'US'

Constant Summary collapse

GEO_MASKED_FORWARDED_HEADERS =

IP-bearing forwarded headers overwritten with the masked IP in the geo-resolution env view. Mirrors the set IPPrivacyMiddleware#mask_forwarded_headers rewrites, so a custom resolver reading env sees masked values everywhere the middleware would. The structured RFC 7239 Forwarded header (HTTP_FORWARDED) is handled separately in #geo_env (dropped, not swapped, to keep valid syntax).

%w[
  HTTP_X_FORWARDED_FOR
  HTTP_X_REAL_IP
  HTTP_X_CLIENT_IP
].freeze

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(env, config, geo_headers_trusted: true) ⇒ RedactedFingerprint

Create a new RedactedFingerprint from a Rack environment

Parameters:

  • env (Hash) —

    Rack environment hash

  • config (Otto::Privacy::Config) —

    Privacy configuration

  • geo_headers_trusted (Boolean) (defaults to: true) —

    whether request geo headers may be trusted for this request. The middleware passes false for a non-trusted-proxy request when trusted proxies are configured, so spoofed geo headers are ignored. Defaults to true for standalone use.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 48

def initialize(env, config, geo_headers_trusted: true)
  remote_ip = env['REMOTE_ADDR']

  @session_id = SecureRandom.uuid
  @timestamp = Time.now.utc
  @masked_ip = IPPrivacy.mask_ip(remote_ip, config.octet_precision)
  @hashed_ip = IPPrivacy.hash_ip(remote_ip, config.rotation_key)
  # hashed_ip is computed above from the real IP; geo resolution then runs
  # against a MASKED view — the masked IP AND an env with the IP-bearing
  # headers masked — so neither a custom resolver nor the database can see
  # the unmasked address, via the argument or via env. Country-level
  # networks are >= /24, so the /24-masked IP resolves to the same country.
  @country = if config.geo_enabled
               GeoResolver.resolve(@masked_ip, geo_env(env), config, headers_trusted: geo_headers_trusted)
             end
  # ASN keeps the masked-IP contract: IPv4 routes are not announced longer
  # than /24, so a masked address falls in the same announced prefix and
  # therefore the same ASN.
  @asn = AsnResolver.resolve(@masked_ip, config) if config.asn_enabled
  # The anonymizer is the one lookup that gets the REAL address, for the
  # same reason hashed_ip above does: masking would destroy the answer.
  # Anonymizer databases list individual egress nodes at or near /32, so a
  # /24-masked lookup would report on the node's neighbours instead of the
  # node. Only the resulting label is retained — the address goes no
  # further than the resolver, exactly as it goes no further than hash_ip.
  @anonymizer = AnonymizerResolver.resolve(remote_ip, config) if config.anonymizer_enabled
  @anonymized_ua = anonymize_user_agent(env['HTTP_USER_AGENT'])
  @request_path = env['PATH_INFO']
  @request_method = env['REQUEST_METHOD']
  @referer = anonymize_referer(env['HTTP_REFERER'])

  freeze
end

Instance Attribute Details

#anonymized_ua ⇒ Object (readonly)

Returns the value of attribute anonymized_ua.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def anonymized_ua
  @anonymized_ua
end

#anonymizer ⇒ Object (readonly)

Returns the value of attribute anonymizer.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def anonymizer
  @anonymizer
end

#asn ⇒ Object (readonly)

Returns the value of attribute asn.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def asn
  @asn
end

#country ⇒ Object (readonly)

Returns the value of attribute country.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def country
  @country
end

#hashed_ip ⇒ Object (readonly)

Returns the value of attribute hashed_ip.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def hashed_ip
  @hashed_ip
end

#masked_ip ⇒ Object (readonly)

Returns the value of attribute masked_ip.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def masked_ip
  @masked_ip
end

#referer ⇒ Object (readonly)

Returns the value of attribute referer.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def referer
  @referer
end

#request_method ⇒ Object (readonly)

Returns the value of attribute request_method.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def request_method
  @request_method
end

#request_path ⇒ Object (readonly)

Returns the value of attribute request_path.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def request_path
  @request_path
end

#session_id ⇒ Object (readonly)

Returns the value of attribute session_id.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def session_id
  @session_id
end

#timestamp ⇒ Object (readonly)

Returns the value of attribute timestamp.



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 24

def timestamp
  @timestamp
end

Instance Method Details

#inspect ⇒ String

Inspect representation

Returns:

  • (String) —

    Detailed representation for debugging



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 119

def inspect
  '#<Otto::Privacy::RedactedFingerprint ' \
    "masked_ip=#{@masked_ip.inspect} " \
    "hashed_ip=#{@hashed_ip[0..15]}... " \
    "country=#{@country.inspect} " \
    "timestamp=#{@timestamp.inspect}>"
end

#to_h ⇒ Hash

Convert to hash for logging or serialization

Returns:

  • (Hash) —

    Hash representation of fingerprint



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 85

def to_h
  {
        session_id: @session_id,
         timestamp: @timestamp.iso8601,
         masked_ip: @masked_ip,
         hashed_ip: @hashed_ip,
           country: @country,
               asn: @asn,
        anonymizer: @anonymizer,
     anonymized_ua: @anonymized_ua,
    request_method: @request_method,
      request_path: @request_path,
           referer: @referer,
  }
end

#to_json(*_args) ⇒ String

Convert to JSON string

Returns:

  • (String) —

    JSON representation



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 104

def to_json(*_args)
  require 'json'
  to_h.to_json
end

#to_s ⇒ String

String representation

Returns:

  • (String) —

    Human-readable representation



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# File 'lib/otto/privacy/redacted_fingerprint.rb', line 112

def to_s
  "#<RedactedFingerprint #{@hashed_ip[0..15]}... #{@country} #{@timestamp}>"
end