Module:IPblock

-- Calculate the minimum-sized blocks of IP addresses that cover each -- IPv4 or IPv6 address entered in the arguments.

local bit32 = require('bit32')

local Collection -- a table to hold items Collection = { add = function (self, item) if item ~= nil then self.n = self.n + 1 self[self.n] = item end end, join = function (self, sep) return table.concat(self, sep) end, remove = function (self, pos) if self.n > 0 and (pos == nil or (0 < pos and pos <= self.n)) then self.n = self.n - 1 return table.remove(self, pos) end end, sort = function (self, comp) table.sort(self, comp) end, new = function return setmetatable({n = 0}, Collection) end } Collection.__index = Collection

local function empty(text) -- Return true if text is nil or empty (assuming a string). return text == nil or text == '' end

local timestamps = {} -- cache local function start_date(code, months) -- Return a timestamp string for a URL to list user contributions -- on and after the returned date. -- The code specifies the wanted format. -- For this module, only recent contributions are wanted, so the -- timestamp is today's date less the given number of months (1 to 12). local key = code .. months if not timestamps[key] then local date = os.date('!*t') -- today's UTC date local y, m, d = date.year, date.month, date.day -- full year, month (1-12), day (1-31) m = m - months if m <= 0 then m = m + 12 y = y - 1 end local limit = m == 2 and 28 or 30 if d > limit then d = limit -- good enough to ensure date is valid end timestamps['y-m-d' .. months] = string.format('%d-%02d-%02d', y, m, d) timestamps['ymdHMS' .. months] = string.format('%d%02d%02d000000', y, m, d)	end return timestamps[key] or '' end

local note_text = { range = '*Links for ranges show the contributions in the previous %s.', gadget = [=[ }
 * Contributions links for IPv6 ranges need the " Allow /16, /24 and /27 – /32 CIDR ranges on Special:Contributions forms " gadget enabled in Special:Preferences, and scripting enabled in the browser.]=],

local function make_note(strings, key) -- Record the fact that a particular note is needed, and return -- wikitext for a link to the note or '' if no link needed. if not strings.nonote then strings.notes = strings.notes or {} if not strings.notes[key] then if key == 'gadget' then strings.notes[key] = note_text[key] elseif key == 'range' then local when = 'month' if strings.months > 1 then when = strings.months .. ' months' end strings.notes[key] = string.format(note_text.range, when) else error('make_note: unexpected key') end end if key == 'gadget' then return ' [note]' end end return '' end

local function describe_total(total, isalloc) -- Return text describing given number of addresses or /64 allocations. if total <= 9999 then -- Can have fractions if total is the number of /64 allocations. if total < 9 then return (string.format('%.1f', total):gsub('%.0$', '')) end return string.format('%.0f', total) end if not isalloc then local alloc = 2^64 if total >= alloc then return describe_total(total / alloc, true) .. ' /64'		end end total = total/1024 local suffix = 'K'	if total >= 1024 then total = total/1024 suffix = 'M'		if total >= 1024 then total = total/1024 suffix = 'G'			if total > 64 then return '>64G' end end end return string.format('%.0f', total) .. suffix end

local function describe_size(ipsize, size) -- Return text describing how many IPs are in a range with size = prefix length. local function numtext(n) if n <= 16 then return tostring(2^n) end if n <= 19 then return tostring(2^(n - 10)) .. 'K'		end if n <= 29 then return tostring(2^(n - 20)) .. 'M'		end if n <= 36 then return tostring(2^(n - 30)) .. 'G'		end return '>64G' end local host = ipsize - size if host <= 32 then -- IPv4 or IPv6. return numtext(host) end -- Must be IPv6. if host <= 64 then local s = ({			[64] = '1', [63] = '50%', [62] = '25%', [61] = '12%',			[60] = '6%', [59] = '3%',  [58] = '2%'		})[host] or '<1%' return s .. ' /64'	end -- IPv6 with size < 64. return numtext(host - 64) .. ' /64' end

local function ipv6_string(ip) -- Return a string equivalent to the given IPv6 address. local z1, z2 -- indices of run of zeros to be displayed as "::" local zstart, zcount for i = 1, 9 do -- Find left-most occurrence of longest run of two or more zeros. if i < 9 and ip[i] == 0 then if zstart then zcount = zcount + 1 else zstart = i				zcount = 1 end else if zcount and zcount > 1 then if not z1 or zcount > z2 - z1 + 1 then z1 = zstart z2 = zstart + zcount - 1 end end zstart = nil zcount = nil end end local parts = Collection.new for i = 1, 8 do		if z1 and z1 <= i and i <= z2 then if i == z1 then if z1 == 1 or z2 == 8 then if z1 == 1 and z2 == 8 then return '::' end parts:add(':') else parts:add('') end end else parts:add(string.format('%x', ip[i])) end end return parts:join(':') end

local function ip_string(ip) -- Return a string equivalent to given IP address (IPv4 or IPv6). if ip.n == 2 then -- IPv4. local parts = {} for i = 1, 2 do			local w = ip[i] local q = i == 1 and 1 or 3 parts[q] = math.floor(w / 256) parts[q+1] = w % 256 end return table.concat(parts, '.') end return ipv6_string(ip) end

-- Metatable for some operations on IP addresses. local ipmt = { __eq = function (lhs, rhs) -- Return true if values in numbered tables match. if lhs.n == rhs.n then for i = 1, lhs.n do				if lhs[i] ~= rhs[i] then return false end end return true end return false end, __lt = function (lhs, rhs) -- Return true if lhs < rhs; for sort. if lhs.n == rhs.n then for i = 1, lhs.n do				if lhs[i] ~= rhs[i] then return lhs[i] < rhs[i] end end return false end return lhs.n < rhs.n -- sort IPv4 before IPv6, although not needed end, }

local function ipv4_address(ip_str) -- Return a collection of two 16-bit words (numbers) equivalent -- to the IPv4 address given as a quad-dotted string, or -- return nil if invalid. -- This representation is for compatibility with IPv6 addresses. local parts = Collection.new local s = ip_str:match('^%s*(.-)%s*$') .. '.'	for item in s:gmatch('(.-)%.') do		parts:add(item) end if parts.n == 4 then for i, s in ipairs(parts) do			if s:match('^%d+$') then local num = tonumber(s) if 0 <= num and num <= 255 then if num > 0 and s:match('^0') then -- A redundant leading zero is an error because it is for an IP in octal. return nil end parts[i] = num else return nil end else return nil end end local result = Collection.new for i = 1, 3, 2 do			result:add(parts[i] * 256 + parts[i+1]) end return setmetatable(result, ipmt) end return nil end

local function ipv6_address(ip_str) -- Return a collection of eight 16-bit words (numbers) equivalent -- to the IPv6 address given as a colon-delimited string, or -- return nil if invalid. local _, n = ip_str:gsub(':', ':') if n < 7 then ip_str, n = ip_str:gsub('::', string.rep(':', 9 - n)) end local parts = Collection.new for item in (ip_str .. ':'):gmatch('(.-):') do		parts:add(item) end if parts.n == 8 then for i, s in ipairs(parts) do			if s == '' then parts[i] = 0 else local num = tonumber('0x' .. s)				if num and 0 <= num and num <= 65535 then parts[i] = num else return nil end end end return setmetatable(parts, ipmt) end return nil end

local function common_length(num1, num2, nr_bits) -- Return number of prefix bits that two integers have in common. -- Number of bits in each number is nr_bits = 16, 8, 4, 2 or 1. if nr_bits <= 1 then return num1 == num2 and 1 or 0 end local half = nr_bits / 2 local splitter = 2^half local upper1, lower1 = math.modf(num1 / splitter) local upper2, lower2 = math.modf(num2 / splitter) if upper1 == upper2 then lower1 = math.floor(lower1 * splitter + 0.5) lower2 = math.floor(lower2 * splitter + 0.5) return half + common_length(lower1, lower2, half) end return common_length(upper1, upper2, half) end

local function common_prefix_length(ip1, ip2) -- Return number of prefix bits that two IPs have in common. -- Caller ensures that both IPs are IPv4 or both are IPv6. local size = 0 for i = 1, ip1.n do		local w1, w2 = ip1[i], ip2[i] if w1 == w2 then size = size + 16 else return size + common_length(w1, w2, 16) end end return size end

local function ip_prefix(ip, length) -- Return a copy of ip masked to contain only the prefix of given length. local result = { n = ip.n } for i = 1, ip.n do		if length > 0 then if length >= 16 then result[i] = ip[i] length = length - 16 else result[i] = bit32.band(ip[i], bit32.arshift(0xffff8000, length - 1)) length = 0 end else result[i] = 0 end end return setmetatable(result, ipmt) end

local function ip_incremented(ip) -- Return a new IP equal to ip + 1. -- Will wraparound (255.255.255.255 + 1 = 0.0.0.0)! local result = { n = ip.n } local carry = 1 for i = ip.n, 1, -1 do		local sum = ip[i] + carry if sum >= 0x10000 then carry = 1 sum = sum - 0x10000 else carry = 0 end result[i] = sum end return setmetatable(result, ipmt) end

local function is_next_ip(ip1, ip2) -- Return true if ip2 is the next IP after ip1 (ip2 == ip1 + 1). -- IPs are sorted and unique so ip1 < ip2 and can ignore wrapping to zero. -- This is lower overhead than making a new incremented IP then comparing. if ip1 and ip2 then local carry = 1 for i = ip1.n, 1, -1 do			local sum = ip1[i] + carry if sum >= 0x10000 then carry = 1 sum = sum - 0x10000 else carry = 0 end if sum ~= ip2[i] then return false end end return true end end

-- Each IP in a range except for the last IP has a 'common' field which is -- a number specifying how many bits are common between the prefixes of this -- IP and the next IP (0 if this IP starts with 0 and the next starts with 1). -- Each non-empty range has exactly one "minimum common", that is, its value -- of common is smaller than all others. That there is only one minimum common -- follows from the fact that the IPs are unique and sorted. local function make_range(iplist, ifirst, ilast) -- Return a table for the range of IPs from iplist[ifirst] to iplist[ilast] inclusive. local imin, vmin, done if ifirst < ilast then for i = ifirst, ilast - 1 do -- Find the (unique) minimum of common lengths. local common = iplist[i].common if vmin then if vmin > common then vmin = common imin = i				end else vmin = common imin = i			end end else vmin = iplist.ipsize imin = ifirst done = true end if vmin > iplist.allocation then -- For IPv6, the default allocation is /64 and there is no point having -- more precise ranges as they add unnecessary complexity. -- However, using results=all sets allocation = 128 so vmin is not changed. vmin = iplist.allocation end return { ifirst = ifirst, -- index of first IP		ilast = ilast,    -- index of last IP		imin = imin,      -- index of IP with minimum common size = vmin,     -- number of common bits in prefix (the minimum) prefix = ip_prefix(iplist[imin], vmin), -- IP table of the base IP		done = done,      -- true if know that this range cannot be improved } end

local function split_range(iplist, range, depth) -- Return a table of two or more ranges that more precisely target -- the IPs in range, or return nothing if unable to improve range. depth = depth and depth + 1 or 0 if depth <= 20 and -- 20 examines 1M contiguous addresses down to individual IPs not range.done and range.size < iplist.allocation and range.ifirst < range.ilast then local imin = range.imin assert(imin and range.ifirst <= imin and imin < range.ilast) local r1 = make_range(iplist, range.ifirst, range.imin) local r2 = make_range(iplist, range.imin + 1, range.ilast) local pointless = range.size + 1 if r1.size > pointless or r2.size > pointless then return { r1, r2 } end local result = Collection.new local function store_split(range) local split = split_range(iplist, range, depth) if split then for _, r in ipairs(split) do					result:add(r) end return true else result:add(range) end end local improved1 = store_split(r1) local improved2 = store_split(r2) if improved1 or improved2 then return result end end range.done = true end

local function better_summary(iplist, summary) -- Return a better summary that more precisely targets the specified IPs, -- or return nil if unable to improve the summary. local better = Collection.new local improved for _, range in ipairs(summary) do		local split = split_range(iplist, range) if split then improved = true for _, r in ipairs(split) do				better:add(r) end else better:add(range) end end return improved and better end

local function make_summaries(iplist) -- Return a collection where each item is a summary. -- A summary is a table of one or more ranges. -- A summary covers all the given IPs and probably more. -- A range is a table representing a CIDR block such as 1.2.248.0/21. -- The first summary found is a single range; each subsequent summary -- (if any) uses more ranges to better target the given IPs. -- The result omits any summary with a range size that is too small (too many IPs). local function good_size(summary) for _, range in ipairs(summary) do			if range.size < iplist.minsize then return false end end return true end local summaries = Collection.new if iplist.n > 0 then for i = 1, iplist.n - 1 do -- Set length of prefixes common between each pair of IPs. iplist[i].common = common_prefix_length(iplist[i], iplist[i+1]) end local summary = { make_range(iplist, 1, iplist.n) } while summary and summaries.n < iplist.maxresults do			if good_size(summary) then summaries:add(summary) end summary = better_summary(iplist, summary) end end return summaries end

local function extract_ipv4(result, omitted, line) -- Extract any IPv4 addresses from given line or throw error. -- Accept CIDR /n to specify a range (only accept 16 to 32). -- Addresses must be delimited with whitespace to reduce false positives. local function store(hit) local n = 32 local lhs, rhs = hit:match('^(.-)/(%d+)$') if lhs then hit = lhs n = tonumber(rhs) if not (n and 16 <= n and n <= 32) then error('CIDR /n only accepts n = 16 to 32, invalid: ' .. lhs .. '/' .. rhs, 0) end end local ip = ipv4_address(hit) if ip then if n == 32 then result:add(ip) else if ip ~= ip_prefix(ip, n) then error('Invalid base address (host bits should be zero): ' .. hit, 0) end for _ = 1, 2^(32 - n) do					result:add(ip) ip = ip_incremented(ip) end end else omitted:add(hit) end end line = line:gsub(':', ' ') -- so wikitext indents or other colons don't obscure an IVp4 address for hit in line:gmatch('%S+') do		if hit:match('^%d+%.%d+[%.%d/]+$') then local _, n = hit:gsub('%.', '.') if n >= 3 then store(hit) end end end end

local function extract_ipv6(result, omitted, line) -- Extract any IPv6 addresses from given line or throw error. -- Addresses must be delimited with whitespace to reduce false positives. -- Want to accept all valid IPv6 despite the fact that contributors will -- not have an address starting with ':'. -- Also want to be able to parse arbitrary wikitext which might use colons -- for indenting. To achieve that, if an address at the start of a line -- is valid, use it; otherwise strip any leading colons and try again. for pos, hit in line:gmatch('(%S+)') do		local ipstr, length = hit:match('^([:%x]+)(/?%d*)$') if ipstr then local _, n = ipstr:gsub(':', ':') if n >= 2 then local ip = ipv6_address(ipstr) if not ip and pos == 1 then ipstr, n = ipstr:gsub('^:+', '') if n > 0 then ip = ipv6_address(ipstr) end end if ip then if length and #length > 0 then error('CIDR /n not accepted for IPv6: ' .. hit, 0) end result:add(ip) else omitted:add(hit) end end end end end

local function contribs(address, strings, ipbase, size) -- Return a URL or wikilink to list the contributions for an IP or IP range, -- or return an empty string if cannot do anything useful. -- The given address is a string of either a single IP or a CIDR range. -- If using old system: --  For IPv6 CIDR, return a Special:Contributions link using an asterisk --  wildcard which should work if the user has enabled the gadget --  "Allow /16, /24 and /27 – /32 CIDR ranges on Special:Contributions". local encoded, count = address:gsub('/', '%%2F') if strings.want_old and count > 0 then make_note(strings, 'range') if address:find(':', 1, true) then if ipbase and size then local digits = math.floor(size / 4) if digits < 3 then digits = 3 end local wildcard = digits % 4 == 0 and ':*' or '*' local parts = {} for i = 1, 8 do					local hex = string.format('%X', ipbase[i]) -- must be uppercase if digits >= 4 then parts[i] = hex digits = digits - 4 if digits <= 0 then break end else local nz -- number of leading zeros in this group of four digits if hex == '0' then nz = 4 else nz = 4 - #hex end if digits <= nz then -- Cannot properly handle this case; have to omit group -- because "0" never occurs as the first digit. wildcard = ':*' else hex = string.rep('0', nz) .. hex -- four digits parts[i] = hex:sub(1, digits) end break end end address = table.concat(parts, ':') .. wildcard local url = 'contribs' -- %s = IPv6 prefix address in uppercase with '*' wildcard at end -- %s = Start date formatted 'yyyymmdd000000' return string.format(url, address, start_date('ymdHMS', strings.months)) .. make_note(strings, 'gadget') end return '' -- no contributions link available end local url = 'contribs' -- %s = IPv4 CIDR range with '/' changed to '%2F' -- %s = Start date formatted 'yyyy-mm-dd' return string.format(url, encoded, start_date('y-m-d', strings.months)) end return 'contribs' end

-- Strings for results using plain text. -- The pre tags used are html which do not provide "nowiki", -- but that is not required by the text used. local plaintext = {

header = [=[ Total      Affected     Given        Range]=],

footer = ' ',

sumfirst = [=[ -- %s%-12s %-12s %-11d %s%s]=], -- %s = empty string (dummy for compatibility) -- %s = total affected -- %s = affected -- %d = given (number of addresses given in input covered by this range) -- %s = IP address range -- %s = empty string

sumnext = [=[ %-12s %-11d %s%s]=], -- %s = affected -- %d = given -- %s = IP address range -- %s = empty string

}

-- Strings for results using a table in wikitext. local wikitable = {

header = [=[ {| class="wikitable" ! Total affected !! Affected addresses !! Given addresses !! Range !! Contribs]=],

footer = '|}',

sumfirst = [=[ -- %s = string of number of ranges in summary (number of rows) -- %s = total affected -- %s = affected -- %d = given -- %s = IP address range -- %s = contributions link
 * - style="background: darkgray; height: 6px;"
 * colspan="5" |
 * - style="vertical-align: top;"
 * rowspan="%s" |%s ||%s ||%d ||%s ||%s]=],

sumnext = [=[ -- %s = affected -- %d = given -- %s = IP address range -- %s = contributions link
 * %s ||%d ||%s ||%s]=],
 * %s ||%d ||%s ||%s]=],

}

local function show_summary(lines, strings, iplist, summary) -- Show the summary by adding table wikitext or plain text to lines. local want_plain = iplist.want_plain local total = 0 for _, range in ipairs(summary) do -- A number is a double which easily handles 2^128 = 3.4e38. total = total + 2^(iplist.ipsize - range.size) end for i, range in ipairs(summary) do		local prefix = ip_string(range.prefix) local size = range.size local affected = describe_size(iplist.ipsize, size) local given = range.ilast - range.ifirst + 1 local address local link = '' if size == iplist.ipsize then address = prefix if not want_plain then link = contribs(address, strings) end else address = prefix .. '/' .. size if not want_plain then link = contribs(address, strings, range.prefix, size) end end local s		if i == 1 then s = string.format(strings.sumfirst,					want_plain and '' or tostring(#summary),					describe_total(total),					affected, given, address, link) else s = string.format(strings.sumnext,					affected, given, address, link) end -- Pre tags returned by a module are html tags, not like wikitext ... .		lines:add(want_plain and mw.text.nowiki(s) or s)	end end

local function process_ips(lines, iplist, omitted) -- Process a list of IP addresses, adding text of results to lines. -- The list should contain either all IPv4 addresses, or all IPv6 (not a mixture). local seq1, seq2, seqmany local function show_sequence if seq1 and seq2 then local text = ip_string(seq1) if seqmany then seqmany = false text = text .. ' – ' .. ip_string(seq2) end seq1 = nil seq2 = nil local markup = text:sub(1, 1) == ':' and ': ' or ':' lines:add(markup .. text) end end local function show_ip(ip) -- Show IP or record it to be included in a "from to" sequence of IPs. if is_next_ip(seq2, ip) then seq2 = ip			seqmany = true else show_sequence seq1 = ip			seq2 = ip			seqmany = false end end if iplist.n < 1 then return end if lines.n > 0 then lines:add('') end if omitted.n > 0 then lines:add('Warning, omitted as invalid: ' .. omitted:join(' ')) lines:add('') end local heading_line if not iplist.nolist then lines:add('') -- this blank line is replaced with a heading heading_line = lines.n	end local duplicates = Collection.new local previous iplist:sort -- Check for duplicates which can interfere with method to get ranges. for i, ip in ipairs(iplist) do		if previous == ip then duplicates:add(i) -- index to omit duplicate later elseif not iplist.nolist then show_ip(ip) end previous = ip	end show_sequence local duplicate_text = '' if duplicates.n > 0 then duplicate_text = ' (after omitting some duplicates)' for i = duplicates.n, 1, -1 do			iplist:remove(duplicates[i]) end end local heading_text = string.format('Sorted %d %s address%s',		iplist.n,		iplist.ipname,		iplist.n == 1 and '' or 'es'		) if heading_line then lines[heading_line] = heading_text .. duplicate_text .. ':'	end local strings = iplist.want_plain and plaintext or wikitable strings.notes = nil -- needed when module is kept loaded for multiple tests strings.want_old = iplist.want_old strings.nonote = iplist.nonote strings.months = iplist.months lines:add(strings.header) local upto = lines.n	for _, summary in ipairs(make_summaries(iplist)) do		show_summary(lines, strings, iplist, summary) end lines:add(strings.footer) if upto + 1 == lines.n then -- Show message in the very unlikely event that no results are found. lines:add('') lines:add('No suitable ranges found; use  to see all ranges.') end if strings.notes then lines:add('') lines:add("Notes") for _, key in ipairs({'range', 'gadget'}) do			if strings.notes[key] then lines:add(strings.notes[key]) end end end end

local function make_options(args) -- Return table of options from validated args or throw error. local options = {} if not empty(args.comment) then options.comment = args.comment end -- Parameter 'months' is only used if 'old' is also used. local months = math.floor(tonumber(args.months) or tonumber(args.month) or 1) if months < 1 then months = 1 elseif months > 12 then months = 12 end options.months = months -- silently ignore invalid input local allocation if not empty(args.allocation) then allocation = tonumber(args.allocation) if not (allocation and 48 <= allocation and allocation <= 128) then error('Invalid allocation "' .. args.allocation .. '" (should be 48 to 128; default is 64)', 0) end end local maxresults if not empty(args.results) then if args.results == 'all' then options.all = true allocation = allocation or 128 maxresults = 1000 else maxresults = tonumber(args.results) if not (maxresults and 1 <= maxresults and maxresults <= 100) then error('Invalid results "' .. args.results .. '" (should be 1 to 100)', 0) end end end options.allocation = allocation or 64 options.maxresults = maxresults or 10 local keywords = { -- Table of k, v strings. -- If an argument matches k, an option named v is set to true. ok = 'noannounce', old = 'want_old', nolist = 'nolist', nonote = 'nonote', text = 'text', }	local want_old for i, arg in ipairs(args) do		local flag = keywords[arg:match('^%s*(%w+)%s*$')] if flag then options[i] = 'skip' options[flag] = true if flag == 'want_old' then want_old = true end end end if not want_old then options.nonote = true end return options end

local function _IPblock(args) -- Process given args; can be called from another module. -- Throw an error if need to report a problem. local options = make_options(args) local v4list, v4omitted = Collection.new, Collection.new local v6list, v6omitted = Collection.new, Collection.new v4list.ipsize = 32 v4list.ipname = 'IPv4' v6list.ipsize = 128 v6list.ipname = 'IPv6' v4list.allocation = 32 v6list.allocation = options.allocation if options.all then v4list.minsize = 0 v6list.minsize = 0 else v4list.minsize = 16 -- cannot block more IPs than /16 for IPv4 v6list.minsize = 19 -- or /19 for IPv6 ($wgBlockCIDRLimit) end for _, k in ipairs({'maxresults', 'months', 'want_old', 'nolist', 'nonote'}) do		v4list[k] = options[k] v6list[k] = options[k] end if options.text then v4list.want_plain = true v6list.want_plain = true end for i, arg in ipairs(args) do		if options[i] ~= 'skip' then for line in string.gmatch(arg .. '\n', '[\t ]*(.-)[\t\r ]*\n') do -- Skip line if is empty or a comment. if line ~= '' then local comment = options.comment if not (comment and line:sub(1, #comment) == comment) then line = line :gsub('[Ss]pecial:[Cc]ontrib%w*/', ' ') -- so input "Special:Contributions/1.2.3.4" works :gsub('[Tt]alk:', ' ') :gsub('[Uu]ser:', ' ') :gsub('[!"#&\'+,%-;<=>?[%]_{|}]', ' ') -- replace accepted delimiters with a space							:gsub('\226\128\142', ' ')  -- replace LTR marks (U+200E)						extract_ipv4(v4list, v4omitted, line)						extract_ipv6(v6list, v6omitted, line)					end				end			end		end	end	if v4list.n < 1 and v6list.n < 1 then		error('No valid IPv4 or IPv6 address in arguments', 0)	end	local lines = Collection.new	if not options.noannounce then		-- 1: Commented out April 2016 as expired.		-- 1: lines:add("Please see this announcement.")		-- 2: Commented out December 2017 as expired.		-- 2: lines:add("By default, links now use Special:Contributions per this announcement.")	end	process_ips(lines, v4list, v4omitted)	process_ips(lines, v6list, v6omitted)	return lines:join('\n') end

local function IPblock(frame) -- Return wikitext to display the smallest IPv4 or IPv6 CIDR range that -- covers each address given in the arguments, or return error text. -- Input can have any mixture of IPs; IPv4 and IPv6 are processed separately. local ok, msg = pcall(_IPblock, frame:getParent.args) if ok then return msg end return ' Error: ' .. msg .. ' ' end

local function sha1(frame) -- Return SHA-1 hash of first parameter. -- This is for use at User:Johnuniq/Security to generate hash of a password. local text = (frame.args[1] or ''):match("^%s*(.-)%s*$") if text ~= '' then return 'SHA-1 hash after removing any leading or trailing whitespace is ' end return 'Usage:  to display the SHA-1 hash of  .' end

return { IPblock = IPblock, _IPblock = _IPblock, sha1 = sha1, }