diff options
author | Vsevolod Stakhov <vsevolod@highsecure.ru> | 2017-03-11 13:14:53 +0000 |
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committer | Vsevolod Stakhov <vsevolod@highsecure.ru> | 2017-03-11 13:14:53 +0000 |
commit | 256b3305e80f0bc6cbbc34e58d68ca1555719ab9 (patch) | |
tree | b0f1693e16d9c38ddd397c29afdb01b37b1cd9ce /rules | |
parent | 698d4c87099a1b65a01b7f6179cacc9c867d726d (diff) | |
download | rspamd-256b3305e80f0bc6cbbc34e58d68ca1555719ab9.tar.gz rspamd-256b3305e80f0bc6cbbc34e58d68ca1555719ab9.zip |
[Minor] Move rules from misc lua to headers and subject checks
Diffstat (limited to 'rules')
-rw-r--r-- | rules/headers_checks.lua | 562 | ||||
-rw-r--r-- | rules/misc.lua | 533 | ||||
-rw-r--r-- | rules/rspamd.lua | 2 | ||||
-rw-r--r-- | rules/subject_checks.lua | 68 |
4 files changed, 633 insertions, 532 deletions
diff --git a/rules/headers_checks.lua b/rules/headers_checks.lua new file mode 100644 index 000000000..765643c72 --- /dev/null +++ b/rules/headers_checks.lua @@ -0,0 +1,562 @@ +--[[ +Copyright (c) 2017, Vsevolod Stakhov <vsevolod@highsecure.ru> + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +]]-- + +local util = require "rspamd_util" +local ipairs = ipairs +local table = table +local fun = require "fun" +local E = {} + +rspamd_config.CHECK_RECEIVED = { + callback = function (task) + local received = task:get_received_headers() + received = fun.filter(function(h) + return not h['artificial'] + end, received):totable() + task:insert_result('RCVD_COUNT_' .. #received, 1.0) + end +} + +rspamd_config.HAS_X_PRIO = { + callback = function (task) + local xprio = task:get_header('X-Priority'); + if not xprio then return false end + local _,_,x = xprio:find('^%s?(%d+)'); + if (x) then + task:insert_result('HAS_X_PRIO_' .. x, 1.0) + end + end +} + +local check_replyto_id = rspamd_config:register_callback_symbol('CHECK_REPLYTO', 1.0, + function (task) + local replyto = task:get_header('Reply-To') + if not replyto then return false end + local rt = util.parse_mail_address(replyto) + if not (rt and rt[1]) then + task:insert_result('REPLYTO_UNPARSEABLE', 1.0) + return false + else + task:insert_result('HAS_REPLYTO', 1.0) + local rta = rt[1].addr + if rta then + -- Check if Reply-To address starts with title seen in display name + local sym = task:get_symbol('FROM_NAME_HAS_TITLE') + local title = (((sym or E)[1] or E).options or E)[1] + if title then + rta = rta:lower() + if rta:find('^' .. title) then + task:insert_result('REPLYTO_EMAIL_HAS_TITLE', 1.0) + end + end + end + end + + -- See if Reply-To matches From in some way + local from = task:get_from(2) + local from_h = task:get_header('From') + if not (from and from[1]) then return false end + if (from_h and from_h == replyto) then + -- From and Reply-To are identical + task:insert_result('REPLYTO_EQ_FROM', 1.0) + else + if (from and from[1]) then + -- See if From and Reply-To addresses match + if (from[1].addr:lower() == rt[1].addr:lower()) then + task:insert_result('REPLYTO_ADDR_EQ_FROM', 1.0) + elseif from[1].domain and rt[1].domain then + if (from[1].domain:lower() == rt[1].domain:lower()) then + task:insert_result('REPLYTO_DOM_EQ_FROM_DOM', 1.0) + else + task:insert_result('REPLYTO_DOM_NEQ_FROM_DOM', 1.0) + end + end + -- See if the Display Names match + if (from[1].name and rt[1].name and from[1].name:lower() == rt[1].name:lower()) then + task:insert_result('REPLYTO_DN_EQ_FROM_DN', 1.0) + end + end + end + end +) + +rspamd_config:register_symbol{ + name = 'REPLYTO_UNPARSEABLE', + score = 1.0, + parent = check_replyto_id, + type = 'virtual', + description = 'Reply-To header could not be parsed', + group = 'header', +} +rspamd_config:register_symbol{ + name = 'HAS_REPLYTO', + score = 0.0, + parent = check_replyto_id, + type = 'virtual', + description = 'Has Reply-To header', + group = 'header', +} +rspamd_config:register_symbol{ + name = 'REPLYTO_EQ_FROM', + score = 0.0, + parent = check_replyto_id, + type = 'virtual', + description = 'Reply-To header is identical to From header', + group = 'header', +} +rspamd_config:register_symbol{ + name = 'REPLYTO_ADDR_EQ_FROM', + score = 0.0, + parent = check_replyto_id, + type = 'virtual', + description = 'Reply-To header is identical to SMTP From', + group = 'header', +} +rspamd_config:register_symbol{ + name = 'REPLYTO_DOM_EQ_FROM_DOM', + score = 0.0, + parent = check_replyto_id, + type = 'virtual', + description = 'Reply-To domain matches the From domain', + group = 'header', +} +rspamd_config:register_symbol{ + name = 'REPLYTO_DOM_NEQ_FROM_DOM', + score = 0.0, + parent = check_replyto_id, + type = 'virtual', + description = 'Reply-To domain does not match the From domain', + group = 'header', +} +rspamd_config:register_symbol{ + name = 'REPLYTO_DN_EQ_FROM_DN', + score = 0.0, + parent = check_replyto_id, + type = 'virtual', + description = 'Reply-To display name matches From', + group = 'header', +} +rspamd_config:register_symbol{ + name = 'FROM_NAME_HAS_TITLE', + score = 2.0, + parent = check_replyto_id, + type = 'virtual', + description = 'Reply-To header has title', + group = 'header', +} +rspamd_config:register_dependency(check_replyto_id, 'FROM_NAME_HAS_TITLE') + +local check_mime_id = rspamd_config:register_callback_symbol('CHECK_MIME', 1.0, + function (task) + local parts = task:get_parts() + if not parts then return false end + + -- Make sure there is a MIME-Version header + local mv = task:get_header('MIME-Version') + local missing_mime = false + if (not mv) then + missing_mime = true + end + + local found_ma = false + local found_plain = false + local found_html = false + local cte_7bit = false + + for _,p in ipairs(parts) do + local mtype,subtype = p:get_type() + local ctype = mtype:lower() .. '/' .. subtype:lower() + if (ctype == 'multipart/alternative') then + found_ma = true + end + if (ctype == 'text/plain') then + if p:get_cte() == '7bit' then + cte_7bit = true + end + found_plain = true + end + if (ctype == 'text/html') then + if p:get_cte() == '7bit' then + cte_7bit = true + end + found_html = true + end + end + + if missing_mime then + if not (not found_ma and ((found_plain or found_html) and cte_7bit)) then + task:insert_result('MISSING_MIME_VERSION', 1.0) + end + end + + if (found_ma) then + if (not found_plain) then + task:insert_result('MIME_MA_MISSING_TEXT', 1.0) + end + if (not found_html) then + task:insert_result('MIME_MA_MISSING_HTML', 1.0) + end + end + end +) + +rspamd_config:register_symbol{ + name = 'MISSING_MIME_VERSION', + score = 2.0, + parent = check_mime_id, + type = 'virtual', + description = 'MIME-Version header is missing', + group = 'header', +} +rspamd_config:register_symbol{ + name = 'MIME_MA_MISSING_TEXT', + score = 2.0, + parent = check_mime_id, + type = 'virtual', + description = 'MIME multipart/alternative missing text/plain part', + group = 'header', +} +rspamd_config:register_symbol{ + name = 'MIME_MA_MISSING_HTML', + score = 1.0, + parent = check_mime_id, + type = 'virtual', + description = 'MIME multipart/alternative missing text/html part', + group = 'header', +} + +-- Used to be called IS_LIST +rspamd_config.PREVIOUSLY_DELIVERED = { + callback = function(task) + if not task:has_recipients(2) then return false end + local to = task:get_recipients(2) + local rcvds = task:get_header_full('Received') + if not rcvds then return false end + for _, rcvd in ipairs(rcvds) do + local _,_,addr = rcvd['decoded']:lower():find("%sfor%s<(.-)>") + if addr then + for _, toa in ipairs(to) do + if toa and toa.addr:lower() == addr then + return true, addr + end + end + return false + end + end + end, + description = 'Message either to a list or was forwarded', + score = 0.0 +} +rspamd_config.BROKEN_HEADERS = { + callback = function(task) + return task:has_flag('broken_headers') + end, + score = 10.0, + group = 'header', + description = 'Headers structure is likely broken' +} + +rspamd_config.BROKEN_CONTENT_TYPE = { + callback = function(task) + return fun.any(function(p) return p:is_broken() end, + task:get_parts()) + end, + score = 1.5, + group = 'header', + description = 'Message has part with broken content type' +} + +rspamd_config.HEADER_RCONFIRM_MISMATCH = { + callback = function (task) + local header_from = nil + local cread = task:get_header('X-Confirm-Reading-To') + + if task:has_from('mime') then + header_from = task:get_from('mime')[1] + end + + local header_cread = nil + if cread then + local headers_cread = util.parse_mail_address(cread) + if headers_cread then header_cread = headers_cread[1] end + end + + if header_from and header_cread then + if not string.find(header_from['addr'], header_cread['addr']) then + return true + end + end + + return false + end, + + score = 2.0, + group = 'header', + description = 'Read confirmation address is different to from address' +} + +rspamd_config.HEADER_FORGED_MDN = { + callback = function (task) + local mdn = task:get_header('Disposition-Notification-To') + if not mdn then return false end + local header_rp = nil + + if task:has_from('smtp') then + header_rp = task:get_from('smtp')[1] + end + + -- Parse mail addr + local headers_mdn = util.parse_mail_address(mdn) + + if headers_mdn and not header_rp then return true end + if header_rp and not headers_mdn then return false end + if not headers_mdn and not header_rp then return false end + + local found_match = false + for _, h in ipairs(headers_mdn) do + if util.strequal_caseless(h['addr'], header_rp['addr']) then + found_match = true + break + end + end + + return (not found_match) + end, + + score = 2.0, + group = 'header', + description = 'Read confirmation address is different to return path' +} + +local headers_unique = { + 'Content-Type', + 'Content-Transfer-Encoding', + -- https://tools.ietf.org/html/rfc5322#section-3.6 + 'Date', + 'From', + 'Sender', + 'Reply-To', + 'To', + 'Cc', + 'Bcc', + 'Message-ID', + 'In-Reply-To', + 'References', + 'Subject' +} + +rspamd_config.MULTIPLE_UNIQUE_HEADERS = { + callback = function(task) + local res = 0 + local res_tbl = {} + + for _,hdr in ipairs(headers_unique) do + local h = task:get_header_full(hdr) + + if h and #h > 1 then + res = res + 1 + table.insert(res_tbl, hdr) + end + end + + if res > 0 then + return true,res,table.concat(res_tbl, ',') + end + + return false + end, + + score = 5.0, + group = 'header', + description = 'Repeated unique headers' +} + +rspamd_config.MISSING_FROM = { + callback = function(task) + local from = task:get_header('From') + if from == nil or from == '' then + return true + end + return false + end, + score = 2.0, + group = 'header', + description = 'Missing From: header' +} +rspamd_config.MV_CASE = { + callback = function (task) + local mv = task:get_header('Mime-Version', true) + if (mv) then return true end + end, + description = 'Mime-Version .vs. MIME-Version', + score = 0.5 +} + +rspamd_config.FAKE_REPLY = { + callback = function (task) + local subject = task:get_header('Subject') + if (subject and subject:lower():find('^re:')) then + local ref = task:get_header('References') + local rt = task:get_header('In-Reply-To') + if (not (ref or rt)) then return true end + end + return false + end, + description = 'Fake reply', + score = 1.0 +} + +local check_from_id = rspamd_config:register_callback_symbol('CHECK_FROM', 1.0, + function(task) + local envfrom = task:get_from(1) + local from = task:get_from(2) + if (from and from[1] and not from[1].name) then + task:insert_result('FROM_NO_DN', 1.0) + elseif (from and from[1] and from[1].name and + from[1].name:lower() == from[1].addr:lower()) then + task:insert_result('FROM_DN_EQ_ADDR', 1.0) + elseif (from and from[1] and from[1].name) then + task:insert_result('FROM_HAS_DN', 1.0) + -- Look for Mr/Mrs/Dr titles + local n = from[1].name:lower() + local match, match_end + match, match_end = n:find('^mrs?[%.%s]') + if match then + task:insert_result('FROM_NAME_HAS_TITLE', 1.0, n:sub(match, match_end-1)) + end + match, match_end = n:find('^dr[%.%s]') + if match then + task:insert_result('FROM_NAME_HAS_TITLE', 1.0, n:sub(match, match_end-1)) + end + -- Check for excess spaces + if n:find('%s%s') then + task:insert_result('FROM_NAME_EXCESS_SPACE', 1.0) + end + end + if (envfrom and from and envfrom[1] and from[1] and + envfrom[1].addr:lower() == from[1].addr:lower()) + then + task:insert_result('FROM_EQ_ENVFROM', 1.0) + elseif (envfrom and envfrom[1] and envfrom[1].addr) then + task:insert_result('FROM_NEQ_ENVFROM', 1.0, from and from[1].addr or '', envfrom[1].addr) + end + + local to = task:get_recipients(2) + if not (to and to[1] and #to == 1 and from) then return false end + -- Check if FROM == TO + if (to[1].addr:lower() == from[1].addr:lower()) then + task:insert_result('TO_EQ_FROM', 1.0) + elseif (to[1].domain and from[1].domain and + to[1].domain:lower() == from[1].domain:lower()) then + task:insert_result('TO_DOM_EQ_FROM_DOM', 1.0) + end + end +) + +rspamd_config:register_virtual_symbol('FROM_NO_DN', 1.0, check_from_id) +rspamd_config:set_metric_symbol('FROM_NO_DN', 0, 'From header does not have a display name') +rspamd_config:register_virtual_symbol('FROM_DN_EQ_ADDR', 1.0, check_from_id) +rspamd_config:set_metric_symbol('FROM_DN_EQ_ADDR', 1.0, 'From header display name is the same as the address') +rspamd_config:register_virtual_symbol('FROM_HAS_DN', 1.0, check_from_id) +rspamd_config:set_metric_symbol('FROM_HAS_DN', 0, 'From header has a display name') +rspamd_config:register_virtual_symbol('FROM_NAME_EXCESS_SPACE', 1.0, check_from_id) +rspamd_config:set_metric_symbol('FROM_NAME_EXCESS_SPACE', 1.0, 'From header display name contains excess whitespace') +rspamd_config:register_virtual_symbol('FROM_NAME_HAS_TITLE', 1.0, check_from_id) +rspamd_config:set_metric_symbol('FROM_NAME_HAS_TITLE', 1.0, 'From header display name has a title (Mr/Mrs/Dr)') +rspamd_config:register_virtual_symbol('FROM_EQ_ENVFROM', 1.0, check_from_id) +rspamd_config:set_metric_symbol('FROM_EQ_ENVFROM', 0, 'From address is the same as the envelope') +rspamd_config:register_virtual_symbol('FROM_NEQ_ENVFROM', 1.0, check_from_id) +rspamd_config:set_metric_symbol('FROM_NEQ_ENVFROM', 0, 'From address is different to the envelope') +rspamd_config:register_virtual_symbol('TO_EQ_FROM', 1.0, check_from_id) +rspamd_config:set_metric_symbol('TO_EQ_FROM', 0, 'To address matches the From address') +rspamd_config:register_virtual_symbol('TO_DOM_EQ_FROM_DOM', 1.0, check_from_id) +rspamd_config:set_metric_symbol('TO_DOM_EQ_FROM_DOM', 0, 'To domain is the same as the From domain') + +local check_to_cc_id = rspamd_config:register_callback_symbol('CHECK_TO_CC', 1.0, + function(task) + local rcpts = task:get_recipients(1) + local to = task:get_recipients(2) + local to_match_envrcpt = 0 + if (not to) then return false end + -- Add symbol for recipient count + if (#to > 50) then + task:insert_result('RCPT_COUNT_GT_50', 1.0) + else + task:insert_result('RCPT_COUNT_' .. #to, 1.0) + end + -- Check for display names + local to_dn_count = 0 + local to_dn_eq_addr_count = 0 + for _, toa in ipairs(to) do + -- To: Recipients <noreply@dropbox.com> + if (toa['name'] and (toa['name']:lower() == 'recipient' + or toa['name']:lower() == 'recipients')) then + task:insert_result('TO_DN_RECIPIENTS', 1.0) + end + if (toa['name'] and toa['name']:lower() == toa['addr']:lower()) then + to_dn_eq_addr_count = to_dn_eq_addr_count + 1 + elseif (toa['name']) then + to_dn_count = to_dn_count + 1 + end + -- See if header recipients match envrcpts + if (rcpts) then + for _, rcpt in ipairs(rcpts) do + if (toa and toa['addr'] and rcpt and rcpt['addr'] and + rcpt['addr']:lower() == toa['addr']:lower()) + then + to_match_envrcpt = to_match_envrcpt + 1 + end + end + end + end + if (to_dn_count == 0 and to_dn_eq_addr_count == 0) then + task:insert_result('TO_DN_NONE', 1.0) + elseif (to_dn_count == #to) then + task:insert_result('TO_DN_ALL', 1.0) + elseif (to_dn_count > 0) then + task:insert_result('TO_DN_SOME', 1.0) + end + if (to_dn_eq_addr_count == #to) then + task:insert_result('TO_DN_EQ_ADDR_ALL', 1.0) + elseif (to_dn_eq_addr_count > 0) then + task:insert_result('TO_DN_EQ_ADDR_SOME', 1.0) + end + + -- See if header recipients match envelope recipients + if (to_match_envrcpt == #to) then + task:insert_result('TO_MATCH_ENVRCPT_ALL', 1.0) + elseif (to_match_envrcpt > 0) then + task:insert_result('TO_MATCH_ENVRCPT_SOME', 1.0) + end + end +) + +rspamd_config:register_virtual_symbol('TO_DN_RECIPIENTS', 1.0, check_to_cc_id) +rspamd_config:set_metric_symbol('TO_DN_RECIPIENTS', 2.0, 'To header display name is "Recipients"') +rspamd_config:register_virtual_symbol('TO_DN_NONE', 1.0, check_to_cc_id) +rspamd_config:set_metric_symbol('TO_DN_NONE', 0, 'None of the recipients have display names') +rspamd_config:register_virtual_symbol('TO_DN_ALL', 1.0, check_to_cc_id) +rspamd_config:set_metric_symbol('TO_DN_ALL', 0, 'All of the recipients have display names') +rspamd_config:register_virtual_symbol('TO_DN_SOME', 1.0, check_to_cc_id) +rspamd_config:set_metric_symbol('TO_DN_SOME', 0, 'Some of the recipients have display names') +rspamd_config:register_virtual_symbol('TO_DN_EQ_ADDR_ALL', 1.0, check_to_cc_id) +rspamd_config:set_metric_symbol('TO_DN_EQ_ADDR_ALL', 0, 'All of the recipients have display names that are the same as their address') +rspamd_config:register_virtual_symbol('TO_DN_EQ_ADDR_SOME', 1.0, check_to_cc_id) +rspamd_config:set_metric_symbol('TO_DN_EQ_ADDR_SOME', 0, 'Some of the recipients have display names that are the same as their address') +rspamd_config:register_virtual_symbol('TO_MATCH_ENVRCPT_ALL', 1.0, check_to_cc_id) +rspamd_config:set_metric_symbol('TO_MATCH_ENVRCPT_ALL', 0, 'All of the recipients match the envelope') +rspamd_config:register_virtual_symbol('TO_MATCH_ENVRCPT_SOME', 1.0, check_to_cc_id) +rspamd_config:set_metric_symbol('TO_MATCH_ENVRCPT_SOME', 0, 'Some of the recipients match the envelope')
\ No newline at end of file diff --git a/rules/misc.lua b/rules/misc.lua index 1c69b7243..30a3d57ba 100644 --- a/rules/misc.lua +++ b/rules/misc.lua @@ -1,5 +1,5 @@ --[[ -Copyright (c) 2011-2015, Vsevolod Stakhov <vsevolod@highsecure.ru> +Copyright (c) 2011-2017, Vsevolod Stakhov <vsevolod@highsecure.ru> Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. @@ -19,61 +19,6 @@ limitations under the License. local E = {} local fun = require "fun" local util = require "rspamd_util" -local rspamd_regexp = require "rspamd_regexp" - --- Uncategorized rules -local subject_re = rspamd_regexp.create('/^(?:(?:Re|Fwd|Fw|Aw|Antwort|Sv):\\s*)+(.+)$/i') - --- Local functions - - --- Subject issues -local function test_subject(task, check_function, rate) - local function normalize_linear(a, x) - local f = a * x - return true, (( f < 1 ) and f or 1), tostring(x) - end - - local sbj = task:get_header('Subject') - - if sbj then - local stripped_subject = subject_re:search(sbj, false, true) - if stripped_subject and stripped_subject[1] and stripped_subject[1][2] then - sbj = stripped_subject[1][2] - end - - local l = util.strlen_utf8(sbj) - if check_function(sbj, l) then - return normalize_linear(rate, l) - end - end - - return false -end - -rspamd_config.SUBJ_ALL_CAPS = { - callback = function(task) - local caps_test = function(sbj) - return util.is_uppercase(sbj) - end - return test_subject(task, caps_test, 1.0/40.0) - end, - score = 3.0, - group = 'subject', - description = 'All capital letters in subject' -} - -rspamd_config.LONG_SUBJ = { - callback = function(task) - local length_test = function(_, len) - return len > 200 - end - return test_subject(task, length_test, 1.0/400.0) - end, - score = 3.0, - group = 'subject', - description = 'Subject is too long' -} -- Different text parts rspamd_config.R_PARTS_DIFFER = { @@ -174,129 +119,6 @@ rspamd_config.R_SUSPICIOUS_URL = { group = 'url' } -rspamd_config.BROKEN_HEADERS = { - callback = function(task) - return task:has_flag('broken_headers') - end, - score = 10.0, - group = 'header', - description = 'Headers structure is likely broken' -} - -rspamd_config.BROKEN_CONTENT_TYPE = { - callback = function(task) - return fun.any(function(p) return p:is_broken() end, - task:get_parts()) - end, - score = 1.5, - group = 'header', - description = 'Message has part with broken content type' -} - -rspamd_config.HEADER_RCONFIRM_MISMATCH = { - callback = function (task) - local header_from = nil - local cread = task:get_header('X-Confirm-Reading-To') - - if task:has_from('mime') then - header_from = task:get_from('mime')[1] - end - - local header_cread = nil - if cread then - local headers_cread = util.parse_mail_address(cread) - if headers_cread then header_cread = headers_cread[1] end - end - - if header_from and header_cread then - if not string.find(header_from['addr'], header_cread['addr']) then - return true - end - end - - return false - end, - - score = 2.0, - group = 'header', - description = 'Read confirmation address is different to from address' -} - -rspamd_config.HEADER_FORGED_MDN = { - callback = function (task) - local mdn = task:get_header('Disposition-Notification-To') - if not mdn then return false end - local header_rp = nil - - if task:has_from('smtp') then - header_rp = task:get_from('smtp')[1] - end - - -- Parse mail addr - local headers_mdn = util.parse_mail_address(mdn) - - if headers_mdn and not header_rp then return true end - if header_rp and not headers_mdn then return false end - if not headers_mdn and not header_rp then return false end - - local found_match = false - for _, h in ipairs(headers_mdn) do - if util.strequal_caseless(h['addr'], header_rp['addr']) then - found_match = true - break - end - end - - return (not found_match) - end, - - score = 2.0, - group = 'header', - description = 'Read confirmation address is different to return path' -} - -local headers_unique = { - 'Content-Type', - 'Content-Transfer-Encoding', - -- https://tools.ietf.org/html/rfc5322#section-3.6 - 'Date', - 'From', - 'Sender', - 'Reply-To', - 'To', - 'Cc', - 'Bcc', - 'Message-ID', - 'In-Reply-To', - 'References', - 'Subject' -} - -rspamd_config.MULTIPLE_UNIQUE_HEADERS = { - callback = function (task) - local res = 0 - local res_tbl = {} - - for _,hdr in ipairs(headers_unique) do - local h = task:get_header_full(hdr) - - if h and #h > 1 then - res = res + 1 - table.insert(res_tbl, hdr) - end - end - - if res > 0 then - return true,res,table.concat(res_tbl, ',') - end - - return false - end, - - score = 5.0, - group = 'header', - description = 'Repeated unique headers' -} rspamd_config.ENVFROM_PRVS = { callback = function (task) @@ -391,19 +213,6 @@ rspamd_config.RCVD_TLS_ALL = { group = "encryption" } -rspamd_config.MISSING_FROM = { - callback = function(task) - local from = task:get_header('From') - if from == nil or from == '' then - return true - end - return false - end, - score = 2.0, - group = 'header', - description = 'Missing From: header' -} - rspamd_config.RCVD_HELO_USER = { callback = function (task) -- Check HELO argument from MTA @@ -453,346 +262,6 @@ rspamd_config.HAS_ATTACHMENT = { description = 'Message contains attachments' } -rspamd_config.MV_CASE = { - callback = function (task) - local mv = task:get_header('Mime-Version', true) - if (mv) then return true end - end, - description = 'Mime-Version .vs. MIME-Version', - score = 0.5 -} - -rspamd_config.FAKE_REPLY = { - callback = function (task) - local subject = task:get_header('Subject') - if (subject and subject:lower():find('^re:')) then - local ref = task:get_header('References') - local rt = task:get_header('In-Reply-To') - if (not (ref or rt)) then return true end - end - return false - end, - description = 'Fake reply', - score = 1.0 -} - -local check_from_id = rspamd_config:register_callback_symbol('CHECK_FROM', 1.0, - function(task) - local envfrom = task:get_from(1) - local from = task:get_from(2) - if (from and from[1] and not from[1].name) then - task:insert_result('FROM_NO_DN', 1.0) - elseif (from and from[1] and from[1].name and - from[1].name:lower() == from[1].addr:lower()) then - task:insert_result('FROM_DN_EQ_ADDR', 1.0) - elseif (from and from[1] and from[1].name) then - task:insert_result('FROM_HAS_DN', 1.0) - -- Look for Mr/Mrs/Dr titles - local n = from[1].name:lower() - local match, match_end - match, match_end = n:find('^mrs?[%.%s]') - if match then - task:insert_result('FROM_NAME_HAS_TITLE', 1.0, n:sub(match, match_end-1)) - end - match, match_end = n:find('^dr[%.%s]') - if match then - task:insert_result('FROM_NAME_HAS_TITLE', 1.0, n:sub(match, match_end-1)) - end - -- Check for excess spaces - if n:find('%s%s') then - task:insert_result('FROM_NAME_EXCESS_SPACE', 1.0) - end - end - if (envfrom and from and envfrom[1] and from[1] and - envfrom[1].addr:lower() == from[1].addr:lower()) - then - task:insert_result('FROM_EQ_ENVFROM', 1.0) - elseif (envfrom and envfrom[1] and envfrom[1].addr) then - task:insert_result('FROM_NEQ_ENVFROM', 1.0, from and from[1].addr or '', envfrom[1].addr) - end - - local to = task:get_recipients(2) - if not (to and to[1] and #to == 1 and from) then return false end - -- Check if FROM == TO - if (to[1].addr:lower() == from[1].addr:lower()) then - task:insert_result('TO_EQ_FROM', 1.0) - elseif (to[1].domain and from[1].domain and - to[1].domain:lower() == from[1].domain:lower()) then - task:insert_result('TO_DOM_EQ_FROM_DOM', 1.0) - end - end -) - -rspamd_config:register_virtual_symbol('FROM_NO_DN', 1.0, check_from_id) -rspamd_config:set_metric_symbol('FROM_NO_DN', 0, 'From header does not have a display name') -rspamd_config:register_virtual_symbol('FROM_DN_EQ_ADDR', 1.0, check_from_id) -rspamd_config:set_metric_symbol('FROM_DN_EQ_ADDR', 1.0, 'From header display name is the same as the address') -rspamd_config:register_virtual_symbol('FROM_HAS_DN', 1.0, check_from_id) -rspamd_config:set_metric_symbol('FROM_HAS_DN', 0, 'From header has a display name') -rspamd_config:register_virtual_symbol('FROM_NAME_EXCESS_SPACE', 1.0, check_from_id) -rspamd_config:set_metric_symbol('FROM_NAME_EXCESS_SPACE', 1.0, 'From header display name contains excess whitespace') -rspamd_config:register_virtual_symbol('FROM_NAME_HAS_TITLE', 1.0, check_from_id) -rspamd_config:set_metric_symbol('FROM_NAME_HAS_TITLE', 1.0, 'From header display name has a title (Mr/Mrs/Dr)') -rspamd_config:register_virtual_symbol('FROM_EQ_ENVFROM', 1.0, check_from_id) -rspamd_config:set_metric_symbol('FROM_EQ_ENVFROM', 0, 'From address is the same as the envelope') -rspamd_config:register_virtual_symbol('FROM_NEQ_ENVFROM', 1.0, check_from_id) -rspamd_config:set_metric_symbol('FROM_NEQ_ENVFROM', 0, 'From address is different to the envelope') -rspamd_config:register_virtual_symbol('TO_EQ_FROM', 1.0, check_from_id) -rspamd_config:set_metric_symbol('TO_EQ_FROM', 0, 'To address matches the From address') -rspamd_config:register_virtual_symbol('TO_DOM_EQ_FROM_DOM', 1.0, check_from_id) -rspamd_config:set_metric_symbol('TO_DOM_EQ_FROM_DOM', 0, 'To domain is the same as the From domain') - -local check_to_cc_id = rspamd_config:register_callback_symbol('CHECK_TO_CC', 1.0, - function(task) - local rcpts = task:get_recipients(1) - local to = task:get_recipients(2) - local to_match_envrcpt = 0 - if (not to) then return false end - -- Add symbol for recipient count - if (#to > 50) then - task:insert_result('RCPT_COUNT_GT_50', 1.0) - else - task:insert_result('RCPT_COUNT_' .. #to, 1.0) - end - -- Check for display names - local to_dn_count = 0 - local to_dn_eq_addr_count = 0 - for _, toa in ipairs(to) do - -- To: Recipients <noreply@dropbox.com> - if (toa['name'] and (toa['name']:lower() == 'recipient' - or toa['name']:lower() == 'recipients')) then - task:insert_result('TO_DN_RECIPIENTS', 1.0) - end - if (toa['name'] and toa['name']:lower() == toa['addr']:lower()) then - to_dn_eq_addr_count = to_dn_eq_addr_count + 1 - elseif (toa['name']) then - to_dn_count = to_dn_count + 1 - end - -- See if header recipients match envrcpts - if (rcpts) then - for _, rcpt in ipairs(rcpts) do - if (toa and toa['addr'] and rcpt and rcpt['addr'] and - rcpt['addr']:lower() == toa['addr']:lower()) - then - to_match_envrcpt = to_match_envrcpt + 1 - end - end - end - end - if (to_dn_count == 0 and to_dn_eq_addr_count == 0) then - task:insert_result('TO_DN_NONE', 1.0) - elseif (to_dn_count == #to) then - task:insert_result('TO_DN_ALL', 1.0) - elseif (to_dn_count > 0) then - task:insert_result('TO_DN_SOME', 1.0) - end - if (to_dn_eq_addr_count == #to) then - task:insert_result('TO_DN_EQ_ADDR_ALL', 1.0) - elseif (to_dn_eq_addr_count > 0) then - task:insert_result('TO_DN_EQ_ADDR_SOME', 1.0) - end - - -- See if header recipients match envelope recipients - if (to_match_envrcpt == #to) then - task:insert_result('TO_MATCH_ENVRCPT_ALL', 1.0) - elseif (to_match_envrcpt > 0) then - task:insert_result('TO_MATCH_ENVRCPT_SOME', 1.0) - end - end -) - -rspamd_config:register_virtual_symbol('TO_DN_RECIPIENTS', 1.0, check_to_cc_id) -rspamd_config:set_metric_symbol('TO_DN_RECIPIENTS', 2.0, 'To header display name is "Recipients"') -rspamd_config:register_virtual_symbol('TO_DN_NONE', 1.0, check_to_cc_id) -rspamd_config:set_metric_symbol('TO_DN_NONE', 0, 'None of the recipients have display names') -rspamd_config:register_virtual_symbol('TO_DN_ALL', 1.0, check_to_cc_id) -rspamd_config:set_metric_symbol('TO_DN_ALL', 0, 'All of the recipients have display names') -rspamd_config:register_virtual_symbol('TO_DN_SOME', 1.0, check_to_cc_id) -rspamd_config:set_metric_symbol('TO_DN_SOME', 0, 'Some of the recipients have display names') -rspamd_config:register_virtual_symbol('TO_DN_EQ_ADDR_ALL', 1.0, check_to_cc_id) -rspamd_config:set_metric_symbol('TO_DN_EQ_ADDR_ALL', 0, 'All of the recipients have display names that are the same as their address') -rspamd_config:register_virtual_symbol('TO_DN_EQ_ADDR_SOME', 1.0, check_to_cc_id) -rspamd_config:set_metric_symbol('TO_DN_EQ_ADDR_SOME', 0, 'Some of the recipients have display names that are the same as their address') -rspamd_config:register_virtual_symbol('TO_MATCH_ENVRCPT_ALL', 1.0, check_to_cc_id) -rspamd_config:set_metric_symbol('TO_MATCH_ENVRCPT_ALL', 0, 'All of the recipients match the envelope') -rspamd_config:register_virtual_symbol('TO_MATCH_ENVRCPT_SOME', 1.0, check_to_cc_id) -rspamd_config:set_metric_symbol('TO_MATCH_ENVRCPT_SOME', 0, 'Some of the recipients match the envelope') - -rspamd_config.CHECK_RECEIVED = { - callback = function (task) - local received = task:get_received_headers() - received = fun.filter(function(h) - return not h['artificial'] - end, received):totable() - task:insert_result('RCVD_COUNT_' .. #received, 1.0) - end -} - -rspamd_config.HAS_X_PRIO = { - callback = function (task) - local xprio = task:get_header('X-Priority'); - if not xprio then return false end - local _,_,x = xprio:find('^%s?(%d+)'); - if (x) then - task:insert_result('HAS_X_PRIO_' .. x, 1.0) - end - end -} - -local check_replyto_id = rspamd_config:register_callback_symbol('CHECK_REPLYTO', 1.0, - function (task) - local replyto = task:get_header('Reply-To') - if not replyto then return false end - local rt = util.parse_mail_address(replyto) - if not (rt and rt[1]) then - task:insert_result('REPLYTO_UNPARSEABLE', 1.0) - return false - else - task:insert_result('HAS_REPLYTO', 1.0) - local rta = rt[1].addr - if rta then - -- Check if Reply-To address starts with title seen in display name - local sym = task:get_symbol('FROM_NAME_HAS_TITLE') - local title = (((sym or E)[1] or E).options or E)[1] - if title then - rta = rta:lower() - if rta:find('^' .. title) then - task:insert_result('REPLYTO_EMAIL_HAS_TITLE', 1.0) - end - end - end - end - - -- See if Reply-To matches From in some way - local from = task:get_from(2) - local from_h = task:get_header('From') - if not (from and from[1]) then return false end - if (from_h and from_h == replyto) then - -- From and Reply-To are identical - task:insert_result('REPLYTO_EQ_FROM', 1.0) - else - if (from and from[1]) then - -- See if From and Reply-To addresses match - if (from[1].addr:lower() == rt[1].addr:lower()) then - task:insert_result('REPLYTO_ADDR_EQ_FROM', 1.0) - elseif from[1].domain and rt[1].domain then - if (from[1].domain:lower() == rt[1].domain:lower()) then - task:insert_result('REPLYTO_DOM_EQ_FROM_DOM', 1.0) - else - task:insert_result('REPLYTO_DOM_NEQ_FROM_DOM', 1.0) - end - end - -- See if the Display Names match - if (from[1].name and rt[1].name and from[1].name:lower() == rt[1].name:lower()) then - task:insert_result('REPLYTO_DN_EQ_FROM_DN', 1.0) - end - end - end - end -) - -rspamd_config:register_virtual_symbol('REPLYTO_UNPARSEABLE', 1.0, check_replyto_id) -rspamd_config:set_metric_symbol('REPLYTO_UNPARSEABLE', 1.0, 'Reply-To header could not be parsed') -rspamd_config:register_virtual_symbol('HAS_REPLYTO', 1.0, check_replyto_id) -rspamd_config:set_metric_symbol('HAS_REPLYTO', 0, 'Has Reply-To header') -rspamd_config:register_virtual_symbol('REPLYTO_EQ_FROM', 1.0, check_replyto_id) -rspamd_config:set_metric_symbol('REPLYTO_EQ_FROM', 0, 'Reply-To header is identical to From header') -rspamd_config:register_virtual_symbol('REPLYTO_ADDR_EQ_FROM', 1.0, check_replyto_id) -rspamd_config:set_metric_symbol('REPLYTO_ADDR_EQ_FROM', 0, 'Reply-To address is the same as From') -rspamd_config:register_virtual_symbol('REPLYTO_DOM_EQ_FROM_DOM', 1.0, check_replyto_id) -rspamd_config:set_metric_symbol('REPLYTO_DOM_EQ_FROM_DOM', 0, 'Reply-To domain matches the From domain') -rspamd_config:register_virtual_symbol('REPLYTO_DOM_NEQ_FROM_DOM', 1.0, check_replyto_id) -rspamd_config:set_metric_symbol('REPLYTO_DOM_NEQ_FROM_DOM', 0, 'Reply-To domain does not match the From domain') -rspamd_config:register_virtual_symbol('REPLYTO_DN_EQ_FROM_DN', 1.0, check_replyto_id) -rspamd_config:set_metric_symbol('REPLYTO_DN_EQ_FROM_DN', 0, 'Reply-To display name matches From') -rspamd_config:register_virtual_symbol('REPLYTO_EMAIL_HAS_TITLE', 1.0, check_replyto_id) -rspamd_config:set_metric_symbol('REPLYTO_EMAIL_HAS_TITLE', 2.0, check_replyto_id) -rspamd_config:register_dependency(check_replyto_id, 'FROM_NAME_HAS_TITLE') - -local check_mime_id = rspamd_config:register_callback_symbol('CHECK_MIME', 1.0, - function (task) - local parts = task:get_parts() - if not parts then return false end - - -- Make sure there is a MIME-Version header - local mv = task:get_header('MIME-Version') - local missing_mime = false - if (not mv) then - missing_mime = true - end - - local found_ma = false - local found_plain = false - local found_html = false - local cte_7bit = false - - for _,p in ipairs(parts) do - local mtype,subtype = p:get_type() - local ctype = mtype:lower() .. '/' .. subtype:lower() - if (ctype == 'multipart/alternative') then - found_ma = true - end - if (ctype == 'text/plain') then - if p:get_cte() == '7bit' then - cte_7bit = true - end - found_plain = true - end - if (ctype == 'text/html') then - if p:get_cte() == '7bit' then - cte_7bit = true - end - found_html = true - end - end - - if missing_mime then - if not (not found_ma and ((found_plain or found_html) and cte_7bit)) then - task:insert_result('MISSING_MIME_VERSION', 1.0) - end - end - - if (found_ma) then - if (not found_plain) then - task:insert_result('MIME_MA_MISSING_TEXT', 1.0) - end - if (not found_html) then - task:insert_result('MIME_MA_MISSING_HTML', 1.0) - end - end - end -) - -rspamd_config:register_virtual_symbol('MISSING_MIME_VERSION', 1.0, check_mime_id) -rspamd_config:set_metric_symbol('MISSING_MIME_VERSION', 2.0, 'MIME-Version header is missing') -rspamd_config:register_virtual_symbol('MIME_MA_MISSING_TEXT', 1.0, check_mime_id) -rspamd_config:set_metric_symbol('MIME_MA_MISSING_TEXT', 2.0, 'MIME multipart/alternative missing text/plain part') -rspamd_config:register_virtual_symbol('MIME_MA_MISSING_HTML', 1.0, check_mime_id) -rspamd_config:set_metric_symbol('MIME_MA_MISSING_HTML', 1.0, 'multipart/alternative missing text/html part') - --- Used to be called IS_LIST -rspamd_config.PREVIOUSLY_DELIVERED = { - callback = function(task) - if not task:has_recipients(2) then return false end - local to = task:get_recipients(2) - local rcvds = task:get_header_full('Received') - if not rcvds then return false end - for _, rcvd in ipairs(rcvds) do - local _,_,addr = rcvd['decoded']:lower():find("%sfor%s<(.-)>") - if addr then - for _, toa in ipairs(to) do - if toa and toa.addr:lower() == addr then - return true, addr - end - end - return false - end - end - end, - description = 'Message either to a list or was forwarded', - score = 0.0 -} - -- Requires freemail maps loaded in multimap local function freemail_reply_neq_from(task) local frt = task:get_symbol('FREEMAIL_REPLYTO') diff --git a/rules/rspamd.lua b/rules/rspamd.lua index a89f0a002..c17b8380e 100644 --- a/rules/rspamd.lua +++ b/rules/rspamd.lua @@ -30,6 +30,8 @@ dofile(local_rules .. '/regexp/misc.lua') dofile(local_rules .. '/regexp/upstream_spam_filters.lua') dofile(local_rules .. '/regexp/compromised_hosts.lua') dofile(local_rules .. '/html.lua') +dofile(local_rules .. '/headers_checks.lua') +dofile(local_rules .. '/subject_checks.lua') dofile(local_rules .. '/misc.lua') dofile(local_rules .. '/http_headers.lua') dofile(local_rules .. '/forwarding.lua') diff --git a/rules/subject_checks.lua b/rules/subject_checks.lua new file mode 100644 index 000000000..d5760ed25 --- /dev/null +++ b/rules/subject_checks.lua @@ -0,0 +1,68 @@ +--[[ +Copyright (c) 2017, Vsevolod Stakhov <vsevolod@highsecure.ru> + +Licensed under the Apache License, Version 2.0 (the "License"); +you may not use this file except in compliance with the License. +You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software +distributed under the License is distributed on an "AS IS" BASIS, +WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +See the License for the specific language governing permissions and +limitations under the License. +]]-- + +local rspamd_regexp = require "rspamd_regexp" +local util = require "rspamd_util" + +-- Uncategorized rules +local subject_re = rspamd_regexp.create('/^(?:(?:Re|Fwd|Fw|Aw|Antwort|Sv):\\s*)+(.+)$/i') + +local function test_subject(task, check_function, rate) + local function normalize_linear(a, x) + local f = a * x + return true, (( f < 1 ) and f or 1), tostring(x) + end + + local sbj = task:get_header('Subject') + + if sbj then + local stripped_subject = subject_re:search(sbj, false, true) + if stripped_subject and stripped_subject[1] and stripped_subject[1][2] then + sbj = stripped_subject[1][2] + end + + local l = util.strlen_utf8(sbj) + if check_function(sbj, l) then + return normalize_linear(rate, l) + end + end + + return false +end + +rspamd_config.SUBJ_ALL_CAPS = { + callback = function(task) + local caps_test = function(sbj) + return util.is_uppercase(sbj) + end + return test_subject(task, caps_test, 1.0/40.0) + end, + score = 3.0, + group = 'subject', + description = 'All capital letters in subject' +} + +rspamd_config.LONG_SUBJ = { + callback = function(task) + local length_test = function(_, len) + return len > 200 + end + return test_subject(task, length_test, 1.0/400.0) + end, + score = 3.0, + group = 'subject', + description = 'Subject is too long' +}
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