// IfsMail.decl - Interim File System Interim Mail System // Copyright Xerox Corporation 1979, 1980, 1981 // Last modified April 1, 1981 10:04 AM by Taft // Overview // // Mail arrives either from a mail user program such as Laurel, or // from another mail system such as another Ifs or Maxc, or from // some job inside IFS (mailer, printer, etc). // The Mail Transfer Protocol is spoken over a Byte Stream Protocol // connection after rendezvousing at the well known Mail Server socket. // The IFS mail system uses two types of job: MTPServers and MailJob. // An MTPServer accepts mail from the net and queues it for MailJob. // MailJob sorts newly arrived mail and forwards queued mail. // Sorting consists of enumerating new mail files and appending copies // either to a local mailbox or to a queue file for another mail server. // Forwarding consists of enumerating the queue files and trying to send // them to remote mail servers. MailJob is an MTP user. // Control // // The entire Mail system can be turned on or off by toggling MS.enabled. // If this bit is off, all mail-related activity is disabled: // no mail will be stored or retrieved, // no mail will be sorted to local mail boxes, and // no mail will be forwarded to other sites. // The Forwarder can be turned on or off by toggling MS.forward. // Disabling forwarding allows IFS to support a closed mail community. // If this bit is off: // no mail will be accepted for non-local mailboxes, and // no mail will be forwarded to other sites. // Distribution lists // // A mail server is also an Ftp server. Requests to retrieve a file // are intercepted. The job is logged in as "Mail", and the requested // filename is prefixed with a system parameter string and postfixed // with ".dl". The retrieve is then allowed to proceed. // Grapevine support // // Two system parameters permit an IFS mail server to cooperate with // the new mail system which will eventually replace it. // If a 'registry' string is specified, recipients ending in ".registry" // will be treated as if the registry resolved to the mail server address. // If a 'gvName' string is specified, all mail for non-local // mailboxes is forwarded there. If this string is not set by the // mail system administrator, mail is forwarded to the recipient // name's registry. // Undeliverable mail // // If a message is undeliverable, then it is returned to its sender. // If the recipient of an undeliverable message is the dead letter // department, then the message is discarded without a trace. // The name of the dead letter department is a system parameter. // Otherwise, a new message is created with the following contents: // // To: (sender eq Mailer.ThisHost? DeadLetter, Sender) // From: Mailer.ThisHost // Subject: Undeliverable mail // // Undeliverable to: <list of recipients> // ----------------------- // <message> // Statistics // // Statistics are kept on five items; three things are recorded: // Samples: total number of times a value was recorded. // Average: average value of the statistic. // Histogarm: eight slot logarithmically scaled histogram of values. // The five items are: // Length (characters) - length of a message received by the mail server. // Recipients - the number of recipients (To: plus cc:) of a message. // Sort delay (sec) - time between receiving a message and appending // copies to local mailboxes or queueing copies for forwarding. // Fwd delay (sec) - time between queueing a message for a remote // mail server and sucessfully delivering it. // Retrieve delay (min) - time between appending a message to a mailbox // and the recipient retrieving it. // Messages that are discarded as undeliverable are counted. // File conventions // // A Mail File consists of 0 or more Messages. // A Message consists of a Header, some Blocks and some Text. // A Header (structure MH) describes a message. // It contains pointers to the Block and Text areas, lengths, etc. // A Block (structure MB) consists of a Type, a Length, and a Body. // The Type describes the format of the block. // The Length is the length of the block IN WORDS including itself. // The Body is arbitrary stuff whose format depends on the block type. // The Text is a sequence of bytes. Its length may be odd, // in which case it is followed by a garbage padding byte. // // 32-bit byte positions are used in the header. // All components (Message, Header, Block, Text, etc.) begin on // word boundaries and are even numbers of bytes long. // // <Mail>New>Mail!* is mail awaiting sorting by MailJob. // <Mail>Box>User!1 is mail awaiting retrieval by User. // <Mail>Fwd>Host!1 is mail awaiting forwarding to Host. manifest [ socketMail = 7 // well known Pup socket mhSeal = 110b // MH seal mhVersion = 2 // MH format version msVersion = 1 // MS format version msStatsVersion = 2 // MS.stats format version deliveryTimeout = 48 // hours after which a msg is deemed undeliverable jobInterval = 5*60 // seconds between background MailJob activations minSortInterval = 5*60 // attempt to sort file no more often than this minForwardInterval = 10*60 // attempt to forward file no more often than this eventInterval = 5 // seconds between Mail Events openTimeout = 5 // seconds to open a file, retrying once a second maxMailParamChars = 39 // max string length in MS structure lenMailParamString = (maxMailParamChars+2) rshift 1 fPropTypeMsgID = 300b // FPROP type private to IFS mail server // MailBox Exception codes ecUnspecified = 700 // 0 Unspecified failure ecCantLocate = 701 // 1 Can't locate mailbox ecNotResident = 702 // 2 Mailbox isn't local & forwarding disabled ecNameToAddress = 704 // 4 Unable to convert registry name to address ecDeliveryTimeout = 705 // Undeliverable after 48 hours ecIllegalRegistry = 706 // 4 Registry does not resolve to MTP socket ecNoRegistry = 707 // 4 Name does not contain a registry ecFwdLoop = 708 // 4 Message forwarding in a loop // Mail Transfer Protocol No codes ecMlbxRequired = 710 // 40 MLBX property required. ecMlbxNotUnamOrCnam = 711 // 41 Mailbox must be User-Name or Connect-Name. ecNoMailbox = 712 // 41 No mailbox by that name here. ecMailNotRetrieved = 713 // 110 Mail not retrieved: $P ecMailNotStored = 714 // 110 Mail not stored: $P ecSndrRequired = 715 // 110 Sender property missing ecAnonRetrieve = 716 // 3 Mail-server Retrieve not allowed ecNoValidMlbx = 717 // 40 No valid recipients for message ecZeroLengthMsg = 718 // 110 Message has zero length ecRegistryNotLocal = 719 // 100 Registry is not local // Mail system IFS error codes ecBadMsgSeal = 720 // Bad MH.seal in msg $1O ecEofInHdr = 721 // Unexpected EOF in Hdr area of msg $1O ecEofInBlk = 722 // Unexpected EOF in Blk area of msg $1O ecEofInTxt = 723 // Unexpected EOF in Txt area of msg $1O ecMlbxIndex = 724 // Can't find mlbx index $1D in msg $2O ecLeaderProps = 725 // FPROP area in leader page $1O overflowed ecMlbxDelFailed = 726 // Failed to delete mailbox ] //--------------------------------------------------------------------------- structure Mail: // Mail System state kept in core //--------------------------------------------------------------------------- [ wake word // eventIntervals until next MailJob creation ctx word // -> MailJob ctx or 0 if not active ui word // -> ui: userName = System, connName = mail rs word // -> MTP Rendezvous socket (NOT a -> PupSoc) msgID word 2 // message ID flags word = [ enabled bit // mail system is enabled forward bit // forwarding is enabled workToDo bit // there is work for MailJob blank bit 13 ] ] manifest lenMail = size Mail/16 //---------------------------------------------------------------------------- structure MSE: // Mail Statistics Entry //---------------------------------------------------------------------------- [ max bit 4 // = 7, max histogram entry index grain bit 4 // log(2) ratio between successive entries scale bit 4 // log(2) value of first entry scaleTotal bit 4 // log(2) scale factor for total calls↑0,1 word // total number of samples total↑0,1 word // (sum of sample values)/(2↑totalScale) histogram↑0,7 word 2 ] manifest lenMSE = size MSE/16 //---------------------------------------------------------------------------- structure MS: // Mail System state kept in file <System>Info //---------------------------------------------------------------------------- [ flags word = [ enabled bit // mail system enabled forward bit // inter-site forwarding enabled blank bit 6 version byte // = msVersion ] deadLtr word lenMailParamString // name of dead letter destination nameDirDL word lenMailParamString // directory containing distribution lists registry word lenMailParamString // grapevine registry we are part of gvName word lenMailParamString // name of grapevine server blank word 128-4*lenMailParamString statsVersion word // = msStatsVersion stats word = [ timeReset word 2 // time statistics were last reset discard word 2 // number of messages discarded mseLen @MSE // length of message in bytes mseMlbx @MSE // number of mailboxes mseSort @MSE // time spent in <Mail>New>Mail mseRetr @MSE // time spent in <Mail>Box>User mseFwd @MSE // time spent in <Mail>Fwd>Host ] ] manifest lenMS = size MS/16 manifest lenMSStats = lenMS - offset MS.stats/16 manifest // Mail Stat types [ msTypeDiscard = 1 msTypeLen = 2 msTypeMlbx = 3 msTypeSort = 4 msTypeRetr = 5 msTypeFwd = 6 ] //--------------------------------------------------------------------------- structure MH: // Message Header //--------------------------------------------------------------------------- [ seal byte // = mhSeal version byte // = mhVersion date word 2 // date msg was put in this file posBlk word 2 // byte pos of first block posSndr word 2 // byte pos of sender block numActive word // number of active recipients posTxt word 2 // byte pos of text lenTxt word 2 // length of text in bytes posBegin word 2 // byte pos of beginning of this message posEnd word 2 // byte pos of end of this message+1 ] manifest lenMH = size MH/16 //--------------------------------------------------------------------------- structure Msg: // An MH with some in-core state added //--------------------------------------------------------------------------- [ stream word // -> disk stream hostQ: // a queue of HQIs [ head word tail word ] gvHQI word // -> HQI for gvName, if there is one uMsg word // -> undeliverable message msg or zero if none mh word = @MH // Message Header from file ] manifest lenMsg = size Msg/16 //--------------------------------------------------------------------------- structure HQI: // Host Queue Item - built by CheckName //--------------------------------------------------------------------------- [ link word ec word // exception code flags word = [ isLocal bit // name maps to our address or matches MS.registry isPartner bit // name maps to address of host giving us mail used bit // at least one recipient name mentions this registry blank bit 13 ] name word // name string begins here ] manifest lenHQI = size HQI/16 //--------------------------------------------------------------------------- structure MB: // Message Block //--------------------------------------------------------------------------- [ type byte // defines format of following words length byte // of block in words including this word ] manifest maxLenMB = 1 lshift size MB.length manifest // MB.type values [ mbTypeFree = 1 // Free block mbTypeMlbx = 2 // MLBX name mbTypeSndr = 3 // SNDR name mbTypeExcp = 4 // Mailbox exception mbTypeTempFree = 5 // See IfsMailForward mbTypeTempExcp = 6 // " ] //--------------------------------------------------------------------------- structure MNB: // MB containing a MailBox or Sender name //--------------------------------------------------------------------------- [ @MB blank word // currently zero ec word // exception code name word 128 // MLBX or SNDR string ] manifest lenMNBHdr = offset MNB.name/16 //--------------------------------------------------------------------------- structure FPropMsgID: // leader page file property //--------------------------------------------------------------------------- [ type bit 8 length bit 8 msgID word 2 ] manifest lenFPropMsgID = size FPropMsgID/16