Adding upstream version 7.94+git20230807.3be01efb1+dfsg.upstream/7.94+git20230807.3be01efb1+dfsgupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 252 insertions, 0 deletions

diff --git a/nselib/datetime.lua b/nselib/datetime.lua
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+--- Functions for dealing with dates and timestamps
+--
+-- @copyright Same as Nmap--See https://nmap.org/book/man-legal.html
+-- @class module
+-- @name datetime
+-- @author Daniel Miller
+
+local stdnse = require "stdnse"
+local os = require "os"
+local math = require "math"
+local string = require "string"
+_ENV = stdnse.module("datetime", stdnse.seeall)
+
+local difftime = os.difftime
+local time = os.time
+local date = os.date
+
+local floor = math.floor
+local fmod = math.fmod
+
+local format = string.format
+local match = string.match
+
+--- Record a time difference between the scanner and the target
+--
+-- The skew will be recorded in the host's registry for later retrieval and
+-- analysis. Adjusts for network distance by subtracting half the smoothed
+-- round-trip time.
+--
+--@param host The host being scanned
+--@param timestamp The target timestamp, in seconds.
+--@param received The local time the stamp was received, in seconds.
+function record_skew(host, timestamp, received)
+  local skew_tab = host.registry.datetime_skew
+  skew_tab = skew_tab or {}
+  -- No srtt? I suppose we'll ignore it, but this could cause problems
+  local srtt = host.times and host.times.srtt or 0
+  local adjusted = difftime(floor(timestamp), floor(received)) - srtt / 2.0
+  skew_tab[#skew_tab + 1] = adjusted
+  stdnse.debug2("record_skew: %s", adjusted)
+  host.registry.datetime_skew = skew_tab
+end
+
+-- Work around Windows error formatting time zones where 1970/1/1 UTC was 1969/12/31
+local utc_offset_seconds
+do
+  -- What does the calendar say locally?
+  local localtime = date("*t", 86400)
+  -- What does the calendar say in UTC?
+  local gmtime = date("!*t", 86400)
+  -- Interpret both as local calendar dates and find the difference.
+  utc_offset_seconds = difftime(time(localtime), time(gmtime))
+end
+
+-- The offset in seconds between local time and UTC.
+--
+-- That is, if we interpret a UTC date table as a local date table by passing
+-- it to os.time, how much must be added to the resulting integer timestamp to
+-- make it correct?
+--
+-- In other words, subtract this value from a timestamp if you intend to use it
+-- in os.date.
+function utc_offset() return utc_offset_seconds end
+
+--- Convert a date table into an integer timestamp.
+--
+-- Unlike os.time, this does not assume that the date table represents a local
+-- time. Rather, it takes an optional offset number of seconds representing the
+-- time zone, and returns the timestamp that would result using that time zone
+-- as local time. If the offset is omitted or 0, the date table is interpreted
+-- as a UTC date. For example, 4:00 UTC is the same as 5:00 UTC+1:
+-- <code>
+-- date_to_timestamp({year=1970,month=1,day=1,hour=4,min=0,sec=0})          --> 14400
+-- date_to_timestamp({year=1970,month=1,day=1,hour=4,min=0,sec=0}, 0)       --> 14400
+-- date_to_timestamp({year=1970,month=1,day=1,hour=5,min=0,sec=0}, 1*60*60) --> 14400
+-- </code>
+-- And 4:00 UTC+1 is an earlier time:
+-- <code>
+-- date_to_timestamp({year=1970,month=1,day=1,hour=4,min=0,sec=0}, 1*60*60) --> 10800
+-- </code>
+function date_to_timestamp(date_t, offset)
+  local status, tm = pcall(time, date_t)
+  if not status then
+    stdnse.debug1("Invalid date for this platform: %s", tm)
+    return nil
+  end
+  offset = offset or 0
+  return tm + utc_offset() - offset
+end
+
+local function format_tz(offset)
+  local sign, hh, mm
+
+  if not offset then
+    return ""
+  end
+  if offset < 0 then
+    sign = "-"
+    offset = -offset
+  else
+    sign = "+"
+  end
+  -- Truncate to minutes.
+  offset = floor(offset / 60)
+  hh = floor(offset / 60)
+  mm = floor(fmod(offset, 60))
+
+  return format("%s%02d:%02d", sign, hh, mm)
+end
+--- Format a date and time (and optional time zone) for structured output.
+--
+-- Formatting is done according to RFC 3339 (a profile of ISO 8601), except
+-- that a time zone may be omitted to signify an unspecified local time zone.
+-- Time zones are given as an integer number of seconds from UTC. Use
+-- <code>0</code> to mark UTC itself. Formatted strings with a time zone look
+-- like this:
+-- <code>
+-- format_timestamp(os.time(), 0)       --> "2012-09-07T23:37:42+00:00"
+-- format_timestamp(os.time(), 2*60*60) --> "2012-09-07T23:37:42+02:00"
+-- </code>
+-- Without a time zone they look like this:
+-- <code>
+-- format_timestamp(os.time())          --> "2012-09-07T23:37:42"
+-- </code>
+--
+-- This function should be used for all dates emitted as part of NSE structured
+-- output.
+function format_timestamp(t, offset)
+  if type(t) == "table" then
+    return format(
+      "%d-%02d-%02dT%02d:%02d:%02d",
+      t.year, t.month, t.day, t.hour, t.min, t.sec
+      )
+  else
+    local tz_string = format_tz(offset)
+    offset = offset or 0
+    local status, result = pcall(date, "!%Y-%m-%dT%H:%M:%S", floor(t + offset))
+    if not status then
+      local tmp = floor(t + offset)
+      local extra_years
+      local seconds_in_year = 31556926
+      if tmp > 0xffffffff then
+        -- Maybe too far in the future?
+        extra_years = (tmp  - 0xffffffff) // seconds_in_year + 1
+      elseif tmp < -utc_offset() then
+        -- Windows can't display times before the epoch
+        extra_years = tmp // seconds_in_year
+      end
+      if extra_years then
+        tmp = tmp - extra_years * seconds_in_year
+        status, result = pcall(date, "!*t", tmp)
+        if status then
+          -- seconds_in_year is imprecise, so we truncate to date only
+          result = format("%d-%02d-%02d?", result.year + extra_years, result.month, result.day)
+        end
+      end
+    end
+    if not status then
+      return ("Invalid timestamp: %s"):format(t)
+    end
+    return result .. tz_string
+  end
+end
+
+--- Format a time interval into a string
+--
+-- String is in the same format as format_difftime
+-- @param interval A time interval
+-- @param unit The time unit division as a number. If <code>interval</code> is
+--             in milliseconds, this is 1000 for instance. Default: 1 (seconds)
+-- @return The time interval in string format
+function format_time(interval, unit)
+  local sign = ""
+  if interval < 0 then
+    sign = "-"
+    interval = math.abs(interval)
+  end
+  unit = unit or 1
+  local precision = floor(math.log(unit, 10))
+
+  local sec = (interval % (60 * unit)) / unit
+  interval = interval // (60 * unit)
+  local min = interval % 60
+  interval = interval // 60
+  local hr = interval % 24
+  interval = interval // 24
+
+  local s = format("%.0fd%02.0fh%02.0fm%02.".. precision .."fs",
+    interval, hr, min, sec)
+  -- trim off leading 0 and "empty" units
+  return sign .. (match(s, "([1-9].*)") or format("%0.".. precision .."fs", 0))
+end
+
+--- Format the difference between times <code>t2</code> and <code>t1</code>
+-- into a string
+--
+-- String is in one of the forms (signs may vary):
+-- * 0s
+-- * -4s
+-- * +2m38s
+-- * -9h12m34s
+-- * +5d17h05m06s
+-- * -2y177d10h13m20s
+-- The string shows <code>t2</code> relative to <code>t1</code>; i.e., the
+-- calculation is <code>t2</code> minus <code>t1</code>.
+function format_difftime(t2, t1)
+  local d, s, sign, yeardiff
+
+  d = difftime(time(t2), time(t1))
+  if d > 0 then
+    sign = "+"
+  elseif d < 0 then
+    sign = "-"
+    t2, t1 = t1, t2
+    d = -d
+  else
+    sign = ""
+  end
+  -- t2 is always later than or equal to t1 here.
+
+  -- The year is a tricky case because it's not a fixed number of days
+  -- the way a day is a fixed number of hours or an hour is a fixed
+  -- number of minutes. For example, the difference between 2008-02-10
+  -- and 2009-02-10 is 366 days because 2008 was a leap year, but it
+  -- should be printed as 1y0d0h0m0s, not 1y1d0h0m0s. We advance t1 to be
+  -- the latest year such that it is still before t2, which means that its
+  -- year will be equal to or one less than t2's. The number of years
+  -- skipped is stored in yeardiff.
+  if t2.year > t1.year then
+    local tmpyear = t1.year
+    -- Put t1 in the same year as t2.
+    t1.year = t2.year
+    d = difftime(time(t2), time(t1))
+    if d < 0 then
+      -- Too far. Back off one year.
+      t1.year = t2.year - 1
+      d = difftime(time(t2), time(t1))
+    end
+    yeardiff = t1.year - tmpyear
+    t1.year = tmpyear
+  else
+    yeardiff = 0
+  end
+
+  local s = format_time(d)
+  if yeardiff == 0 then return sign .. s end
+  -- Years.
+  s = format("%dy", yeardiff) .. s
+  return sign .. s
+end
+
+return _ENV