hashfile

README

hash file

This filter hashes the content of a file.

{
  "filter": [
    {
      "type": "hashfile",
      "field": "file_name",
      "output": "hash",
      "buf_size": 20000,
      "algos": [
        "crc32",
        "md5",
        "sha256",
        "fnv1a",
        "sha512"
      ]
    }
  ]
}

The file to hash is found in the event specified by "field". Alogs are the list of hashes to use. If blank then all supported hashes will be used. The filter will not load if an unknown filter is specified.

The output hash is in its binary form encoded as base64.

Example output:

{
  "hash": {
    "fnv1a": "OObfHVMzKKqDlPRRHpcI3Q==",
    "crc32": "UNbFkg==",
    "md5": "12UcXohM6INPDmCieDpsaQ==",
    "sha256": "5TU5z8hTPQr2yjPaPbWXcvFF7xsUdCBiv/71SCEbynU=",
    "sha512": "R+W447AH2dO4aADxUG2IdyhE5Vg+u4LDHl7pbimYV62FszO+rqkKND+2jQuvzTT1P9lLoJYJZvwcjnL0m8EMZA=="
  }
}

Documentation

Index

• Constants
• Variables
• func InitHandler(ctx context.Context, raw config.ConfigRaw, control config.Control) (config.TypeFilterConfig, error)
• type FilterConfig
  • func DefaultFilterConfig() FilterConfig
  • func (f *FilterConfig) Event(ctx context.Context, event logevent.LogEvent) (logevent.LogEvent, bool)
• type Hash

Constants

const ErrorTag = "gogstash_filter_hashfile_error"

ErrorTag tag added to event when process module failed

const ModuleName = "hashfile"

ModuleName is the name used in config file

Variables

var SupportedHashes map[string]func(interface{}) Hash = make(map[string]func(interface{}) Hash)

SupportedHashes the list of supported hashes and their init functions

Functions

func InitHandler

func InitHandler(ctx context.Context, raw config.ConfigRaw, control config.Control) (config.TypeFilterConfig, error)

InitHandler initialize the filter plugin

Types

type FilterConfig

type FilterConfig struct {
	config.FilterConfig

	Field   string   `json:"field" yaml:"field"`       // field name of file to hash
	Output  string   `json:"output" yaml:"output"`     // field name to store output to
	Algos   []string `json:"algos" yaml:"algos"`       // hash algos to hash on
	BufSize int      `json:"buf_size" yaml:"buf_size"` // buffer size for copy
}

FilterConfig holds the configuration json fields and internal objects

func DefaultFilterConfig

func DefaultFilterConfig() FilterConfig

DefaultFilterConfig returns an FilterConfig struct with default values

func (*FilterConfig) Event

func (f *FilterConfig) Event(ctx context.Context, event logevent.LogEvent) (logevent.LogEvent, bool)

Event the main filter event

type Hash

type Hash interface {
	io.Writer
	Sum() []byte
}

Hash is our interface to a hash. Each hash that implements this interface will work with the module.