Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!cbosgd!ulysses!bellcore!decvax!decwrl!pyramid!pesnta!amd!amdcad!lll-crg!seismo!brl-adm!ron From: ron@brl-adm.UUCP Newsgroups: mod.sources.doc Subject: rfc822 (5 of 5) Message-ID: <726@brl-adm.ARPA> Date: Tue, 20-May-86 00:00:14 EDT Article-I.D.: brl-adm.726 Posted: Tue May 20 00:00:14 1986 Date-Received: Sat, 24-May-86 22:27:45 EDT Distribution: net Organization: Ballistic Research Lab Lines: 580 Approved: RON@BRL.ARPA Standard for ARPA Internet Text Messages enumeration of The Committee, he would not have gotten an implicit reply; the presence of the "Reply-to" field SUPER- SEDES the sending of a reply to the person named in the "From" field. A.2.5. Secretary acting as full agent of author George Jones asks his secretary (Secy@Host) to send a message for him in his capacity as Group. He wants his secre- tary to handle all replies. From: George Jones Sender: Secy@Host Reply-To: Secy@Host A.2.6. Agent for user without online mailbox A friend of George's, Sarah, is visiting. George's secretary sends some mail to a friend of Sarah in computer- land. Replies should go to George, whose mailbox is Jones at Registry. From: Sarah Friendly Sender: Secy-Name Reply-To: Jones@Registry. A.2.7. Agent for member of a committee George's secretary sends out a message which was authored jointly by all the members of a committee. Note that the name of the committee cannot be specified, since names are not permitted in the From field. From: Jones@Host, Smith@Other-Host, Doe@Somewhere-Else Sender: Secy@SHost August 13, 1982 - 38 - RFC #822 Standard for ARPA Internet Text Messages A.3. COMPLETE HEADERS A.3.1. Minimum required Date: 26 Aug 76 1429 EDT Date: 26 Aug 76 1429 EDT From: Jones@Registry.Org or From: Jones@Registry.Org Bcc: To: Smith@Registry.Org Note that the "Bcc" field may be empty, while the "To" field is required to have at least one address. A.3.2. Using some of the additional fields Date: 26 Aug 76 1430 EDT From: George Jones Sender: Secy@SHOST To: "Al Neuman"@Mad-Host, Sam.Irving@Other-Host Message-ID: A.3.3. About as complex as you're going to get Date : 27 Aug 76 0932 PDT From : Ken Davis Subject : Re: The Syntax in the RFC Sender : KSecy@Other-Host Reply-To : Sam.Irving@Reg.Organization To : George Jones , Al.Neuman@MAD.Publisher cc : Important folk: Tom Softwood , "Sam Irving"@Other-Host;, Standard Distribution: /main/davis/people/standard@Other-Host, "standard.dist.3"@Tops-20-Host>; Comment : Sam is away on business. He asked me to handle his mail for him. He'll be able to provide a more accurate explanation when he returns next week. In-Reply-To: , George's message X-Special-action: This is a sample of user-defined field- names. There could also be a field-name "Special-action", but its name might later be preempted Message-ID: <4231.629.XYzi-What@Other-Host> August 13, 1982 - 39 - RFC #822 Standard for ARPA Internet Text Messages B. SIMPLE FIELD PARSING Some mail-reading software systems may wish to perform only minimal processing, ignoring the internal syntax of structured field-bodies and treating them the same as unstructured-field- bodies. Such software will need only to distinguish: o Header fields from the message body, o Beginnings of fields from lines which continue fields, o Field-names from field-contents. The abbreviated set of syntactic rules which follows will suffice for this purpose. It describes a limited view of mes- sages and is a subset of the syntactic rules provided in the main part of this specification. One small exception is that the con- tents of field-bodies consist only of text: B.1. SYNTAX message = *field *(CRLF *text) field = field-name ":" [field-body] CRLF field-name = 1* field-body = *text [CRLF LWSP-char field-body] B.2. SEMANTICS Headers occur before the message body and are terminated by a null line (i.e., two contiguous CRLFs). A line which continues a header field begins with a SPACE or HTAB character, while a line beginning a field starts with a printable character which is not a colon. A field-name consists of one or more printable characters (excluding colon, space, and control-characters). A field-name MUST be contained on one line. Upper and lower case are not dis- tinguished when comparing field-names. August 13, 1982 - 40 - RFC #822 Standard for ARPA Internet Text Messages C. DIFFERENCES FROM RFC #733 The following summarizes the differences between this stan- dard and the one specified in Arpanet Request for Comments #733, "Standard for the Format of ARPA Network Text Messages". The differences are listed in the order of their occurrence in the current specification. C.1. FIELD DEFINITIONS C.1.1. FIELD NAMES These now must be a sequence of printable characters. They may not contain any LWSP-chars. C.2. LEXICAL TOKENS C.2.1. SPECIALS The characters period ("."), left-square bracket ("["), and right-square bracket ("]") have been added. For presentation purposes, and when passing a specification to a system that does not conform to this standard, periods are to be contigu- ous with their surrounding lexical tokens. No linear-white- space is permitted between them. The presence of one LWSP- char between other tokens is still directed. C.2.2. ATOM Atoms may not contain SPACE. C.2.3. SPECIAL TEXT ctext and qtext have had backslash ("\") added to the list of prohibited characters. C.2.4. DOMAINS The lexical tokens and have been added. C.3. MESSAGE SPECIFICATION C.3.1. TRACE The "Return-path:" and "Received:" fields have been specified. August 13, 1982 - 41 - RFC #822 Standard for ARPA Internet Text Messages C.3.2. FROM The "From" field must contain machine-usable addresses (addr- spec). Multiple addresses may be specified, but named-lists (groups) may not. C.3.3. RESENT The meta-construct of prefacing field names with the string "Resent-" has been added, to indicate that a message has been forwarded by an intermediate recipient. C.3.4. DESTINATION A message must contain at least one destination address field. "To" and "CC" are required to contain at least one address. C.3.5. IN-REPLY-TO The field-body is no longer a comma-separated list, although a sequence is still permitted. C.3.6. REFERENCE The field-body is no longer a comma-separated list, although a sequence is still permitted. C.3.7. ENCRYPTED A field has been specified that permits senders to indicate that the body of a message has been encrypted. C.3.8. EXTENSION-FIELD Extension fields are prohibited from beginning with the char- acters "X-". C.4. DATE AND TIME SPECIFICATION C.4.1. SIMPLIFICATION Fewer optional forms are permitted and the list of three- letter time zones has been shortened. C.5. ADDRESS SPECIFICATION August 13, 1982 - 42 - RFC #822 Standard for ARPA Internet Text Messages C.5.1. ADDRESS The use of quoted-string, and the ":"-atom-":" construct, have been removed. An address now is either a single mailbox reference or is a named list of addresses. The latter indi- cates a group distribution. C.5.2. GROUPS Group lists are now required to to have a name. Group lists may not be nested. C.5.3. MAILBOX A mailbox specification may indicate a person's name, as before. Such a named list no longer may specify multiple mailboxes and may not be nested. C.5.4. ROUTE ADDRESSING Addresses now are taken to be absolute, global specifications, independent of transmission paths. The construct has been provided, to permit explicit specification of transmis- sion path. RFC #733's use of multiple at-signs ("@") was intended as a general syntax for indicating routing and/or hierarchical addressing. The current standard separates these specifications and only one at-sign is permitted. C.5.5. AT-SIGN The string " at " no longer is used as an address delimiter. Only at-sign ("@") serves the function. C.5.6. DOMAINS Hierarchical, logical name-domains have been added. C.6. RESERVED ADDRESS The local-part "Postmaster" has been reserved, so that users can be guaranteed at least one valid address at a site. August 13, 1982 - 43 - RFC #822 Standard for ARPA Internet Text Messages D. ALPHABETICAL LISTING OF SYNTAX RULES address = mailbox ; one addressee / group ; named list addr-spec = local-part "@" domain ; global address ALPHA = ; (101-132, 65.- 90.) ; (141-172, 97.-122.) atom = 1* authentic = "From" ":" mailbox ; Single author / ( "Sender" ":" mailbox ; Actual submittor "From" ":" 1#mailbox) ; Multiple authors ; or not sender CHAR = ; ( 0-177, 0.-127.) comment = "(" *(ctext / quoted-pair / comment) ")" CR = ; ( 15, 13.) CRLF = CR LF ctext = may be folded ")", "\" & CR, & including linear-white-space> CTL = ; ( 177, 127.) date = 1*2DIGIT month 2DIGIT ; day month year ; e.g. 20 Jun 82 dates = orig-date ; Original [ resent-date ] ; Forwarded date-time = [ day "," ] date time ; dd mm yy ; hh:mm:ss zzz day = "Mon" / "Tue" / "Wed" / "Thu" / "Fri" / "Sat" / "Sun" delimiters = specials / linear-white-space / comment destination = "To" ":" 1#address ; Primary / "Resent-To" ":" 1#address / "cc" ":" 1#address ; Secondary / "Resent-cc" ":" 1#address / "bcc" ":" #address ; Blind carbon / "Resent-bcc" ":" #address DIGIT = ; ( 60- 71, 48.- 57.) domain = sub-domain *("." sub-domain) domain-literal = "[" *(dtext / quoted-pair) "]" domain-ref = atom ; symbolic reference dtext = may be folded "]", "\" & CR, & including linear-white-space> extension-field = August 13, 1982 - 44 - RFC #822 Standard for ARPA Internet Text Messages field = field-name ":" [ field-body ] CRLF fields = dates ; Creation time, source ; author id & one 1*destination ; address required *optional-field ; others optional field-body = field-body-contents [CRLF LWSP-char field-body] field-body-contents = field-name = 1* group = phrase ":" [#mailbox] ";" hour = 2DIGIT ":" 2DIGIT [":" 2DIGIT] ; 00:00:00 - 23:59:59 HTAB = ; ( 11, 9.) LF = ; ( 12, 10.) linear-white-space = 1*([CRLF] LWSP-char) ; semantics = SPACE ; CRLF => folding local-part = word *("." word) ; uninterpreted ; case-preserved LWSP-char = SPACE / HTAB ; semantics = SPACE mailbox = addr-spec ; simple address / phrase route-addr ; name & addr-spec message = fields *( CRLF *text ) ; Everything after ; first null line ; is message body month = "Jan" / "Feb" / "Mar" / "Apr" / "May" / "Jun" / "Jul" / "Aug" / "Sep" / "Oct" / "Nov" / "Dec" msg-id = "<" addr-spec ">" ; Unique message id optional-field = / "Message-ID" ":" msg-id / "Resent-Message-ID" ":" msg-id / "In-Reply-To" ":" *(phrase / msg-id) / "References" ":" *(phrase / msg-id) / "Keywords" ":" #phrase / "Subject" ":" *text / "Comments" ":" *text / "Encrypted" ":" 1#2word / extension-field ; To be defined / user-defined-field ; May be pre-empted orig-date = "Date" ":" date-time originator = authentic ; authenticated addr [ "Reply-To" ":" 1#address] ) phrase = 1*word ; Sequence of words August 13, 1982 - 45 - RFC #822 Standard for ARPA Internet Text Messages qtext = , ; => may be folded "\" & CR, and including linear-white-space> quoted-pair = "\" CHAR ; may quote any char quoted-string = <"> *(qtext/quoted-pair) <">; Regular qtext or ; quoted chars. received = "Received" ":" ; one per relay ["from" domain] ; sending host ["by" domain] ; receiving host ["via" atom] ; physical path *("with" atom) ; link/mail protocol ["id" msg-id] ; receiver msg id ["for" addr-spec] ; initial form ";" date-time ; time received resent = resent-authentic [ "Resent-Reply-To" ":" 1#address] ) resent-authentic = = "Resent-From" ":" mailbox / ( "Resent-Sender" ":" mailbox "Resent-From" ":" 1#mailbox ) resent-date = "Resent-Date" ":" date-time return = "Return-path" ":" route-addr ; return address route = 1#("@" domain) ":" ; path-relative route-addr = "<" [route] addr-spec ">" source = [ trace ] ; net traversals originator ; original mail [ resent ] ; forwarded SPACE = ; ( 40, 32.) specials = "(" / ")" / "<" / ">" / "@" ; Must be in quoted- / "," / ";" / ":" / "\" / <"> ; string, to use / "." / "[" / "]" ; within a word. sub-domain = domain-ref / domain-literal text = atoms, specials, CR & bare LF, but NOT ; comments and including CRLF> ; quoted-strings are ; NOT recognized. time = hour zone ; ANSI and Military trace = return ; path to sender 1*received ; receipt tags user-defined-field = word = atom / quoted-string August 13, 1982 - 46 - RFC #822 Standard for ARPA Internet Text Messages zone = "UT" / "GMT" ; Universal Time ; North American : UT / "EST" / "EDT" ; Eastern: - 5/ - 4 / "CST" / "CDT" ; Central: - 6/ - 5 / "MST" / "MDT" ; Mountain: - 7/ - 6 / "PST" / "PDT" ; Pacific: - 8/ - 7 / 1ALPHA ; Military: Z = UT; <"> = ; ( 42, 34.) August 13, 1982 - 47 - RFC #822