README
¶
milter
A golang library for milter support heavily inspired from https://github.com/andybalholm/milter For example how to use the library see https://github.com/phalaaxx/pf-milters - postfix milter for email classification with bogofilter and blacklisting messages which contain files with executable extensions.
Documentation
¶
Overview ¶
Modifier object instance is provided to milter handlers to modify email messages
Index ¶
- Constants
- Variables
- func DecodeCStrings(data []byte) []string
- func ReadCString(data []byte) string
- func RunServer(server net.Listener, init MilterInit) error
- type CustomResponse
- type Message
- type Milter
- type MilterInit
- type MilterSession
- type Modifier
- func (m *Modifier) AddHeader(name, value string) error
- func (m *Modifier) AddRecipient(r string) error
- func (m *Modifier) ChangeHeader(index int, name, value string) error
- func (m *Modifier) DeleteRecipient(r string) error
- func (m *Modifier) Quarantine(reason string) error
- func (m *Modifier) ReplaceBody(body []byte) error
- type Response
- type SimpleResponse
Constants ¶
const ( Accept = 'a' Continue = 'c' Discard = 'd' Reject = 'r' TempFail = 't' )
Define milter response codes
const ( RespAccept = SimpleResponse(Accept) RespContinue = SimpleResponse(Continue) RespDiscard = SimpleResponse(Discard) RespReject = SimpleResponse(Reject) RespTempFail = SimpleResponse(TempFail) )
Define standard responses with no data
const ( // negotiation actions OptAddHeader = 1 << iota OptChangeBody OptAddRcpt OptRemoveRcpt OptChangeHeader OptQuarantine OptChangeFrom OptAddRcptWithArgs OptSetMacroList )
const ( // undesired protocol content OptNoConnect = 1 << iota OptNoHelo OptNoMailFrom OptNoRcptTo OptNoBody OptNoHeaders OptNoEOH OptNoReplyToHeaders OptNoUnknown OptNoData OptSkipEventNextTime OptWithRejectedRcpt OptNoReplyToConnect OptNoReplyToHelo OptNoReplyToMail OptNoReplyToRcpt OptNoReplyToData OptNoReplyToUnkn OptNoReplyToEOH OptNoReplyToBody OptHeaderValuesWithLeadingSpace )
const NULL = "\x00"
NULL terminator
Variables ¶
var ( ECloseSession = errors.New("Stop current milter processing") EMacroNoData = errors.New("Macro definition with no data") )
pre-defined errors
Functions ¶
func DecodeCStrings ¶
DecodeCStrings splits c style strings into golang slice
func ReadCString ¶
ReadCString reads and returs c style string from []byte
Types ¶
type CustomResponse ¶
CustomResponse is a response object used by callback handlers to indicate how the milter should continue processing of current message
func NewResponse ¶
func NewResponse(code byte, data []byte) *CustomResponse
NewResponse generates a new CustomRespanse suitable for WritePacket
func NewResponseStr ¶
func NewResponseStr(code byte, data string) *CustomResponse
NewResponseStr generates a new CustomResponse with string payload
func (*CustomResponse) Continue ¶
func (c *CustomResponse) Continue() bool
Continue returns false if milter chain should be stopped, true otherwise
func (*CustomResponse) Response ¶
func (c *CustomResponse) Response() *Message
Response returns message object with data
type Milter ¶
type Milter interface {
// Connect is called to provide SMTP connection data for incoming message
// supress with NoConnect
Connect(string, string, uint16, net.IP, *Modifier) (Response, error)
// Helo is called to process any HELO/EHLO related filters
// supress with NoHelo
Helo(string, *Modifier) (Response, error)
// MailFrom is called to process filters on envelope FROM address
// supress with NoMailForm
MailFrom(string, *Modifier) (Response, error)
// RcptTo is called to process filters on envelope TO address
// supress with NoRcptTo
RcptTo(string, *Modifier) (Response, error)
// Header is called once for each header in incoming message
// supress with NoHeaders
Header(string, string, *Modifier) (Response, error)
// Headers is called when all message headers have been processed
// supress with NoHeaders
Headers(textproto.MIMEHeader, *Modifier) (Response, error)
// BodyChunk is called to process next message body chunk data (up to 64KB in size)
// supress with NoBody
BodyChunk([]byte, *Modifier) (Response, error)
// Body is called when entire message body has been passed to milter
// supress with NoBody
Body(*Modifier) (Response, error)
}
Milter is an interface for milter callback handlers
type MilterInit ¶
MilterInit is a function that initializes milter object options
type MilterSession ¶
type MilterSession struct {
Actions uint32
Protocol uint32
Sock io.ReadWriteCloser
Headers textproto.MIMEHeader
Macros map[string]string
Milter Milter
}
MilterSession is keeps session state during MTA communication
func (*MilterSession) HandleMilterCommands ¶
func (m *MilterSession) HandleMilterCommands()
process all milter commands in the same connection
func (*MilterSession) Process ¶
func (m *MilterSession) Process(msg *Message) (Response, error)
Process incoming milter command
func (*MilterSession) ReadPacket ¶
func (c *MilterSession) ReadPacket() (*Message, error)
ReadPacket reads incoming milter packet
func (*MilterSession) WritePacket ¶
func (m *MilterSession) WritePacket(msg *Message) error
WritePacket sends a milter response packet to socket stream
type Modifier ¶
type Modifier struct {
Macros map[string]string
Headers textproto.MIMEHeader
WritePacket func(*Message) error
}
Modifier provides access to Macros, Headers and Body data to callback handlers. It also defines a
number of functions that can be used by callback handlers to modify processing of the email message
func NewModifier ¶
func NewModifier(s *MilterSession) *Modifier
NewModifier creates a new Modifier object from MilterSession
func (*Modifier) AddRecipient ¶
AddRecipient appends a new envelope recipient for current message
func (*Modifier) ChangeHeader ¶
ChangeHeader replaces the header at the pecified position with a new one
func (*Modifier) DeleteRecipient ¶
DeleteRecipient removes an envelope recipient address from message
func (*Modifier) Quarantine ¶
Quarantine a message by giving a reason to hold it
func (*Modifier) ReplaceBody ¶
ReplaceBody substitutes message body with provided body
type Response ¶
Response represents a response structure returned by callback
handlers to indicate how the milter server should proceed
type SimpleResponse ¶
type SimpleResponse byte
SimpleResponse interface to define list of pre-defined responses
func (SimpleResponse) Continue ¶
func (r SimpleResponse) Continue() bool
Continue to process milter messages only if current code is Continue
func (SimpleResponse) Response ¶
func (r SimpleResponse) Response() *Message
Response returns a Message object reference
Source Files