3 -- Copyright (c) 2009 Mauro Iazzi
5 -- Permission is hereby granted, free of charge, to any person
6 -- obtaining a copy of this software and associated documentation
7 -- files (the "Software"), to deal in the Software without
8 -- restriction, including without limitation the rights to use,
9 -- copy, modify, merge, publish, distribute, sublicense, and/or sell
10 -- copies of the Software, and to permit persons to whom the
11 -- Software is furnished to do so, subject to the following
14 -- The above copyright notice and this permission notice shall be
15 -- included in all copies or substantial portions of the Software.
17 -- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 -- EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
19 -- OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 -- NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
21 -- HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
22 -- WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
23 -- FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
24 -- OTHER DEALINGS IN THE SOFTWARE.
30 -- MIME implementation in Lua
32 -- XXX: at section 3.4
37 local tostring = tostring
39 local setfenv
= setfenv
44 -- this creates a named and substitution capture for the given pattern
45 lpeg
.Csg
= function (patt
)
46 return #lpeg
.Cs(patt
) * lpeg
.Ct(patt
)
48 -- this collects both the table of named captures and the
49 -- substitution captureof the given pattern
50 lpeg
.Cst
= function (patt
)
51 return (#lpeg
.Cs(patt
) * lpeg
.Ct(patt
)) / function (s
, t
)
54 for k
, v
in pairs(t
) do
55 if type(k
)~='number' then
63 -- rfc2822 Section 2.1:
65 -- A message consists of header fields (collectively called "the header
66 -- of the message") followed, optionally, by a body. The header is a
67 -- sequence of lines of characters with special syntax as defined in
68 -- this standard. The body is simply a sequence of characters that
69 -- follows the header and is separated from the header by an empty line
70 -- (i.e., a line with nothing preceding the CRLF).
72 local split_content
= function (c
)
73 -- NOTE: there is no guarantee that the CRLF separating header
74 -- and body is the first one. However no headers admit a blank
76 local h
, b
= string.match(c
, '^(.-)'..CRLF
..CRLF
..'(.*)$')
77 assert(type(h
)=='string' and type(b
)=='string')
81 -- rfc2822 Section 2.2.3
83 -- The process of moving from this folded multiple-line representation
84 -- of a header field to its single line representation is called
85 -- "unfolding". Unfolding is accomplished by simply removing any CRLF
86 -- that is immediately followed by WSP. Each header field should be
87 -- treated in its unfolded form for further syntactic and semantic
90 local unfold_header
= function (h
)
91 return string.gsub(h
, CRLF
..'[ \t]', ' ')
94 -- rfc2822 Section 2.1
96 -- At the most basic level, a message is a series of characters. A
97 -- message that is conformant with this standard is comprised of
98 -- characters with values in the range 1 through 127 and interpreted as
99 -- US-ASCII characters [ASCII]. For brevity, this document sometimes
100 -- refers to this range of characters as simply "US-ASCII characters".
103 -- rfc2822 Section 2.1.1
105 -- There are two limits that this standard places on the number of
106 -- characters in a line. Each line of characters MUST be no more than
107 -- 998 characters, and SHOULD be no more than 78 characters, excluding
110 local check_content
= function (c
)
112 -- TODO: implement in a portable way
116 -- rfc2822 Section 2.3
118 -- The body of a message is simply lines of US-ASCII characters. The
119 -- only two limitations on the body are as follows:
121 -- - CR and LF MUST only occur together as CRLF; they MUST NOT appear
122 -- independently in the body.
124 -- - Lines of characters in the body MUST be limited to 998 characters,
126 -- and SHOULD be limited to 78 characters, excluding the CRLF.
128 local check_body
= function (b
)
134 -- some core values (not implemented literally)
135 -- see RFC 2234 Section 6.1
136 local core_values
= {
137 ["ALPHA"] = lpeg
.R("AZ", "az"),
138 ["BIT"] = lpeg
.P("0") + lpeg
.P("1"),
139 ["CHAR"] = lpeg
.R("\01\127"),
140 ["CR"] = lpeg
.P("\13"),
141 ["CRLF"] = lpeg
.P("\13\10"),
142 ["DIGIT"] = lpeg
.R("09"),
143 ["LF"] = lpeg
.P("\10"),
144 ["WSP"] = lpeg
.S("\32\09"),
147 -- lexical tokens used in the specification
148 -- TODO: could be optimized
149 -- check for non-obfuscated optimizations
150 -- TODO: write in a less obfuscated way
151 -- check if parenthesis can be removed
152 local lex_tokens
= function ()
155 -- control characters without whitespaces
156 ["NO-WS-CTL"] = R("\1\8") +
160 P("\127"), -- RFC 2822 Section 3.2.1
161 -- a character in a text
162 ["text"] = R("\1\9") +
165 R("\14\127"), -- RFC 2822 Section 3.2.1
166 -- a special character
167 ["specials"] = P("(") + P(")") +
173 P("\""), -- RFC 2822 Section 3.2.1
174 -- a quoted pair should return only the second character
175 ["quoted-pair"] = (P("\\")/'' * V("text")) + V("obs-qp"), -- RFC 2822 Section 3.2.2
176 -- a folding white space (a whitespace that can include a CRLF)
177 -- should be substituted by a single whitespace
178 ["FWS"] = (((V("WSP")^
0 * V("CRLF"))^
-1 * V("WSP")^
1) + V("obs-FWS")) / " ", -- RFC 2822 Section 3.2.3
179 -- a text character allowed inside a comment
180 ["ctext"] = V("NO-WS-CTL") +
183 R("\93\126"), -- RFC 2822 Section 3.2.3
184 -- the content of a comment (comments can nest)
185 ["ccontent"] = V("ctext") + V("quoted-pair") + V("comment"), -- RFC 2822 Section 3.2.3
187 -- should be substituted by a single whitespace
188 ["comment"] = (P("(") * (V("FWS")^
-1 * V("ccontent"))^
0 * V("FWS")^
-1 * P(")")) / " ", -- RFC 2822 Section 3.2.3
189 -- a comment or a folding white space
190 -- should be substituted by a single whitespace
192 -- Folding white spaces should not be placed in a way that
193 -- creates lines containing only whitespaces.
194 -- This requirement Is not necessarily enforced by this grammar
195 ["CFWS"] = ( (V("FWS") + (V("comment")*V("FWS")^
-1)) * (V("comment")*V("FWS")^
-1)^
0 ) / " ", -- RFC 2822 Section 3.2.3
196 -- character that can appear in an atom
197 ["atext"] = V("ALPHA") + V("DIGIT") +
207 P("~"), -- RFC 2822 Section 3.2.4
208 -- an atom is equal to the content only discarding comments and whitespace
209 ["atom"] = V("CFWS")^
-1 * C(V("atext")^
1) * V("CFWS")^
-1, -- RFC 2822 Section 3.2.4
210 -- an atom with dots is only the content, discarding CFWSs
211 ["dot-atom"] = Cs((V("CFWS")^
-1/'') * C(V("dot-atom-text")) * (V("CFWS")^
-1/'')), -- RFC 2822 Section 3.2.4
212 -- the content of an atom text with dots
213 ["dot-atom-text"] = V("atext")^
1 * (P(".") * V("atext")^
1)^
0, -- RFC 2822 Section 3.2.4
214 -- character that can appear in a quoted string
215 ["qtext"] = V("NO-WS-CTL") +
218 R("\93\126"), -- RFC 2822 Section 3.2.5
219 -- character or quoted pair (both can appear in a quoted string)
220 -- it is equivalent to the character itself or to the result of the
222 ["qcontent"] = C(V("qtext")) + V("quoted-pair"), -- RFC 2822 Section 3.2.5
223 -- a quoted string is equal to its content
224 ["quoted-string"] = V("CFWS")^
-1 *
225 P("\"") * (V("FWS")^
-1 * V("qcontent"))^
0 * V("FWS")^
-1 * P("\"") * V("CFWS")^
-1, -- RFC 2822 Section 3.2.5
226 -- unstructured patterns for unspecified headers
227 -- what should these be equal to?
230 ["word"] = V("atom") + V("quoted-string"), -- RFC 2822 Section 3.2.6
232 ["phrase"] = V("word")^
1 + V("obs-phrase"), -- RFC 2822 Section 3.2.6
233 -- a character for unstructured text
234 ["utext"] = V("NO-WS-CTL") + R("\33\126") + V("obs-utext"), -- RFC 2822 Section 3.2.6
235 -- an unstructured text
236 ["unstructured"] = (V("FWS")^
-1 * V("utext"))^
0 * V("FWS")^
-1, -- RFC 2822 Section 3.2.6
241 local deb
= function(...) for i
=1,select('#',...) do local v
=select(i
,...)print(type(v
), v
)end end
243 local date_time
= function ()
246 -- date and time specification
247 -- dates and times should be valid
248 -- this grammar does not enforce this yet
249 ["date-time"] = Cst(( V
"day-of-week" * P
"," )^
-1 * V
"date" * V
"FWS" * V
"time" * V
"CFWS"^
-1), -- RFC 2822 Section 3.3
250 ["day-of-week"] = ( V
"FWS"^
-1 * V
"day-name" ) + V
"obs-day-of-week", -- RFC 2822 Section 3.3
251 ["day-name"] = Cg(P
"Mon" + P
"Tue" + P
"Wed" + P
"Thu" + P
"Fri" + P
"Sat" + P
"Sun", "weekday"), -- RFC 2822 Section 3.3
252 ["date"] = V
"day" * V
"month" * V
"year", -- RFC 2822 Section 3.3
253 ["year"] = Cg(C(V
"DIGIT"^
4), "year") + V
"obs-year", -- RFC 2822 Section 3.3
254 ["month"] = (V
"FWS" * V
"month-name" * V
"FWS") + V
"obs-month", -- RFC 2822 Section 3.3
255 ["month-name"] = Cg(C
"Jan" + C
"Feb" + C
"Mar" + C
"Apr" + C
"May" + C
"Jun" + C
"Jul" + C
"Aug" + C
"Sep" + C
"Oct" + C
"Nov" + C
"Dec", "month"), -- RFC 2822 Section 3.3
256 ["day"] = (V
"FWS"^
-1 * Cg(C(V
"DIGIT" * V
"DIGIT"^
-1), "day")) + V
"obs-day", -- RFC 2822 Section 3.3
257 ["time"] = V
"time-of-day" * V
"FWS" * V
"zone", -- RFC 2822 Section 3.3
258 ["time-of-day"] = V
"hour" * P
":" * V
"minute" * (P
":" * V
"second")^
-1, -- RFC 2822 Section 3.3
259 ["hour"] = Cg(C(V
"DIGIT" * V
"DIGIT"), "hour") + V
"obs-hour", -- RFC 2822 Section 3.3
260 ["minute"] = Cg((V
"DIGIT" * V
"DIGIT"), "minute") + V
"obs-minute", -- RFC 2822 Section 3.3
261 ["second"] = Cg((V
"DIGIT" * V
"DIGIT"), "second") + V
"obs-second", -- RFC 2822 Section 3.3
262 ["zone"] = Cg( (P
"+" + P
"-") * V
"DIGIT" * V
"DIGIT" * V
"DIGIT" * V
"DIGIT", "zone" ) + V
"obs-zone", -- RFC 2822 Section 3.3
266 local address
= function ()
269 -- address specification
270 -- dates and times should be valid
271 -- this grammar does not enforce this yet
272 ["address"] = V
"mailbox" + V
"group", -- RFC 2822 Section 3.4
273 ["mailbox"] = V
"name-addr" + V
"addr-spec", -- RFC 2822 Section 3.4
274 ["name-addr"] = V
"display-name"^
-1 * V
"angle-addr", -- RFC 2822 Section 3.4
275 ["angle-addr"] = (V
"CFWS"^
-1 * P
"<" * V
"addr-spec" * P
">" * V
"CFWS"^
-1) + V
"obs-angle-addr", -- RFC 2822 Section 3.4
276 ["group"] = V
"display-name" * P
":" * (V
"mailbox-list" + V
"CFWS") * P
";" * V
"CFWS"^
-1, -- RFC 2822 Section 3.4
277 ["display-name"] = V
"phrase", -- RFC 2822 Section 3.4
278 ["mailbox-list"] = (V
"mailbox" * (P
"," * V
"mailbox")^
0) + V
"obs-mailbox-list", -- RFC 2822 Section 3.4
279 ["address-list"] = (V
"address" * (P
"," * V
"address")^
0) + V
"obs-address-list", -- RFC 2822 Section 3.4
280 -- address specification (name@host.domain)
281 ["addr-spec"] = Cst(V
"local-part" * P
"@" * V
"domain"), -- RFC 2822 Section 3.4.1
282 ["local-part"] = Csg(V
"dot-atom" + V
"quoted-string" + V
"obs-local-part", "box"), -- RFC 2822 Section 3.4.1
283 ["domain"] = Cg(V
"dot-atom" + V
"domain-literal" + V
"obs-domain", "domain"), -- RFC 2822 Section 3.4.1
284 ["domain-literal"] = V
"CFWS"^
-1 * P
"[" * (V
"FWS"^
-1 * V
"dcontent")^
0 * V
"FWS"^
-1 * P
"]" * V
"CFWS"^
-1, -- RFC 2822 Section 3.4.1
285 ["dcontent"] = V
"dtext" + V
"quoted-pair", -- RFC 2822 Section 3.4.1
286 ["dtext"] = V
"NO-WS-CTL" + R
"\33\90" + R
"\94\126", -- RFC 2822 Section 3.4.1
290 local overall_message
= function ()
293 -- overall message specification
295 -- RRC 2822 Section 3.5:
297 -- A message consists of header fields, optionally followed by a message
298 -- body. Lines in a message MUST be a maximum of 998 characters
299 -- excluding the CRLF, but it is RECOMMENDED that lines be limited to 78
300 -- characters excluding the CRLF.
302 -- this grammar does not enforce the 78 chars limit yet
303 ["message"] = (V
"fields" + V
"obs-fields") * (V
"CRLF" * V
"body")^
-1, -- RFC 2822 Section 3.5
304 ["body"] = (V
"text"^
-998 * V
"CRLF")^
0 * V
"text"^
-998, -- RFC 2822 Section 3.5
308 local fields
= function ()
311 -- spec for all fields in the header
313 -- RRC 2822 Section 3.6
315 --the "fields" rule is incomplete
316 ["fields"] = -- trace fields missing
317 (V
"orig-date" + V
"from" + V
"sender" + V
"reply-to" + V
"to" + V
"cc" + V
"bcc"
318 + V
"message-id" + V
"in-reply-to" + V
"to" + V
"cc" + V
"bcc")^
0, -- RFC 2822 Section 3.6
319 -- origination date field: the time at which the author decided
320 -- the message was ready to be sent (e.g. hit the button)
321 ["orig-date"] = P
"Date:" * V
"date-time" * V
"CRLF", -- RFC 2822 Section 3.6.1
322 -- the author of the message
323 ["from"] = P
"From:" * V
"mailbox-list" * V
"CRLF", -- RFC 2822 Section 3.6.2
324 -- the actual agent that sent the message
325 ["sender"] = P
"Sender:" * V
"mailbox" * V
"CRLF", -- RFC 2822 Section 3.6.2
326 -- address which should be replied to
327 -- see Section 3.6.3 for forming replies
328 ["reply-to"] = P
"Reply-To:" * V
"address-list" * V
"CRLF", -- RFC 2822 Section 3.6.2
329 -- The "To:" field contains the address(es) of the primary recipient(s)
331 ["to"] = P
"To:" * V
"address-list" * V
"CRLF", -- RFC 2822 Section 3.6.3
332 -- The "Cc:" field contains the addresses of others who are to receive
333 -- the message, though the content of the message may not be directed
335 ["cc"] = P
"Cc:" * V
"address-list" * V
"CRLF", -- RFC 2822 Section 3.6.3
336 -- The "Bcc:" field contains addresses of recipients of the message
337 -- whose addresses are not to be revealed to other recipients of the
339 ["bcc"] = P
"Bcc:" * (V
"address-list" + V
"CFWS") * V
"CRLF", -- RFC 2822 Section 3.6.3
340 ["message-id"] = P
"Message-Id:" * V
"msg-id" * V
"CRLF", -- RFC 2822 Section 3.6.4
341 ["in-reply-to"] = P
"In-Reply-To:" * V
"msg-id"^
1 * V
"CRLF", -- RFC 2822 Section 3.6.4
342 ["references"] = P
"References:" * V
"msg-id"^
1 * V
"CRLF", -- RFC 2822 Section 3.6.4
343 ["msg-id"] = V
"CFWS"^
-1 * P
"<" * V
"id-left" * P
"@" * V
"id-right" * P
">" * V
"CFWS"^
-1, -- RFC 2822 Section 3.6.4
344 ["id-left"] = V
"dot-atom-text" + V
"no-fold-quote" + V
"obs-id-left", -- RFC 2822 Section 3.6.4
345 ["id-right"] = V
"dot-atom-text" + V
"no-fold-literal" + V
"obs-id-right", -- RFC 2822 Section 3.6.4
346 ["no-fold-quote"] = P
"\"" * (V
"qtext" + V
"quoted-pair")^
0 * P
"\"", -- RFC 2822 Section 3.6.4
347 ["no-fold-literal"] = P
"[" * (V
"dtext" + V
"quoted-pair")^
0 * P
"]", -- RFC 2822 Section 3.6.4
352 ["obs-FWS"] = lpeg
.P(false),
353 ["obs-qp"] = lpeg
.P(false),
354 ["obs-phrase"] = lpeg
.P(false),
355 ["obs-utext"] = lpeg
.P(false),
356 ["obs-day-of-week"] = lpeg
.P(false),
357 ["obs-year"] = lpeg
.P(false),
358 ["obs-month"] = lpeg
.P(false),
359 ["obs-day"] = lpeg
.P(false),
360 ["obs-hour"] = lpeg
.P(false),
361 ["obs-minute"] = lpeg
.P(false),
362 ["obs-second"] = lpeg
.P(false),
363 ["obs-zone"] = lpeg
.P(false),
364 ["obs-angle-addr"] = lpeg
.P(false),
365 ["obs-mailbox-list"] = lpeg
.P(false),
366 ["obs-address-list"] = lpeg
.P(false),
367 ["obs-local-part"] = lpeg
.P(false),
368 ["obs-domain"] = lpeg
.P(false),
369 ["obs-fields"] = lpeg
.P(false),
370 ["obs-id-left"] = lpeg
.P(false),
371 ["obs-id-right"] = lpeg
.P(false),
374 local os
= setmetatable({}, {__index
= function() return lpeg
.P(false) end})
376 local join_set
= function (...)
377 local n
= select('#', ...)
380 local t
= select(i
, ...)
381 if type(t
)=='table' then
382 for k
, v
in pairs(t
) do
385 elseif type(t
)=='string' then
387 elseif type(t
)=='boolean' then
388 -- TODO: check no overwrite
390 error('join_set: bad argument number '..i
..' of type '..type(t
))
396 local gr
= join_set(core_values
, lex_tokens(), date_time(), address(), overall_message(), fields(), obs_strict
)