root/luci/trunk/libs/sys/luasrc/sys.lua @ 8673

--[[
LuCI - System library

Description:
Utilities for interaction with the Linux system

FileId:
$Id$

License:
Copyright 2008 Steven Barth <steven@midlink.org>

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 io     = require "io"
local os     = require "os"
local table  = require "table"
local nixio  = require "nixio"
local fs     = require "nixio.fs"
local uci    = require "luci.model.uci"

local luci  = {}
luci.util   = require "luci.util"
luci.ip     = require "luci.ip"

local tonumber, ipairs, pairs, pcall, type, next, setmetatable, require =
    tonumber, ipairs, pairs, pcall, type, next, setmetatable, require


--- LuCI Linux and POSIX system utilities.
module "luci.sys"

--- Execute a given shell command and return the error code
-- @class       function
-- @name        call
-- @param       ...     Command to call
-- @return      Error code of the command
function call(...)
    return os.execute(...) / 256
end

--- Execute a given shell command and capture its standard output
-- @class       function
-- @name        exec
-- @param command   Command to call
-- @return          String containg the return the output of the command
exec = luci.util.exec

--- Retrieve information about currently mounted file systems.
-- @return  Table containing mount information
function mounts()
    local data = {}
    local k = {"fs", "blocks", "used", "available", "percent", "mountpoint"}
    local ps = luci.util.execi("df")

    if not ps then
        return
    else
        ps()
    end

    for line in ps do
        local row = {}

        local j = 1
        for value in line:gmatch("[^%s]+") do
            row[k[j]] = value
            j = j + 1
        end

        if row[k[1]] then

            -- this is a rather ugly workaround to cope with wrapped lines in
            -- the df output:
            --
            --  /dev/scsi/host0/bus0/target0/lun0/part3
            --                   114382024  93566472  15005244  86% /mnt/usb
            --

            if not row[k[2]] then
                j = 2
                line = ps()
                for value in line:gmatch("[^%s]+") do
                    row[k[j]] = value
                    j = j + 1
                end
            end

            table.insert(data, row)
        end
    end

    return data
end

--- Retrieve environment variables. If no variable is given then a table
-- containing the whole environment is returned otherwise this function returns
-- the corresponding string value for the given name or nil if no such variable
-- exists.
-- @class       function
-- @name        getenv
-- @param var   Name of the environment variable to retrieve (optional)
-- @return      String containg the value of the specified variable
-- @return      Table containing all variables if no variable name is given
getenv = nixio.getenv

--- Get or set the current hostname.
-- @param       String containing a new hostname to set (optional)
-- @return      String containing the system hostname
function hostname(newname)
    if type(newname) == "string" and #newname > 0 then
        fs.writefile( "/proc/sys/kernel/hostname", newname )
        return newname
    else
        return nixio.uname().nodename
    end
end

--- Returns the contents of a documented referred by an URL.
-- @param url    The URL to retrieve
-- @param stream Return a stream instead of a buffer
-- @param target Directly write to target file name
-- @return      String containing the contents of given the URL
function httpget(url, stream, target)
    if not target then
        local source = stream and io.popen or luci.util.exec
        return source("wget -qO- '"..url:gsub("'", "").."'")
    else
        return os.execute("wget -qO '%s' '%s'" %
            {target:gsub("'", ""), url:gsub("'", "")})
    end
end

--- Returns the system load average values.
-- @return  String containing the average load value 1 minute ago
-- @return  String containing the average load value 5 minutes ago
-- @return  String containing the average load value 15 minutes ago
function loadavg()
    local info = nixio.sysinfo()
    return info.loads[1], info.loads[2], info.loads[3]
end

--- Initiate a system reboot.
-- @return  Return value of os.execute()
function reboot()
    return os.execute("reboot >/dev/null 2>&1")
end

--- Returns the system type, cpu name and installed physical memory.
-- @return  String containing the system or platform identifier
-- @return  String containing hardware model information
-- @return  String containing the total memory amount in kB
-- @return  String containing the memory used for caching in kB
-- @return  String containing the memory used for buffering in kB
-- @return  String containing the free memory amount in kB
-- @return  String containing the cpu bogomips (number)
function sysinfo()
    local cpuinfo = fs.readfile("/proc/cpuinfo")
    local meminfo = fs.readfile("/proc/meminfo")

    local memtotal = tonumber(meminfo:match("MemTotal:%s*(%d+)"))
    local memcached = tonumber(meminfo:match("\nCached:%s*(%d+)"))
    local memfree = tonumber(meminfo:match("MemFree:%s*(%d+)"))
    local membuffers = tonumber(meminfo:match("Buffers:%s*(%d+)"))
    local bogomips = tonumber(cpuinfo:match("[Bb]ogo[Mm][Ii][Pp][Ss].-: ([^\n]+)")) or 0

    local system =
        cpuinfo:match("system type\t+: ([^\n]+)") or
        cpuinfo:match("Processor\t+: ([^\n]+)") or
        cpuinfo:match("model name\t+: ([^\n]+)")

    local model =
        luci.util.pcdata(fs.readfile("/tmp/sysinfo/model")) or
        cpuinfo:match("machine\t+: ([^\n]+)") or
        cpuinfo:match("Hardware\t+: ([^\n]+)") or
        luci.util.pcdata(fs.readfile("/proc/diag/model")) or
        nixio.uname().machine or
        system

    return system, model, memtotal, memcached, membuffers, memfree, bogomips
end

--- Retrieves the output of the "logread" command.
-- @return  String containing the current log buffer
function syslog()
    return luci.util.exec("logread")
end

--- Retrieves the output of the "dmesg" command.
-- @return  String containing the current log buffer
function dmesg()
    return luci.util.exec("dmesg")
end

--- Generates a random id with specified length.
-- @param bytes Number of bytes for the unique id
-- @return      String containing hex encoded id
function uniqueid(bytes)
    local rand = fs.readfile("/dev/urandom", bytes)
    return rand and nixio.bin.hexlify(rand)
end

--- Returns the current system uptime stats.
-- @return  String containing total uptime in seconds
function uptime()
    return nixio.sysinfo().uptime
end


--- LuCI system utilities / network related functions.
-- @class   module
-- @name    luci.sys.net
net = {}

--- Returns the current arp-table entries as two-dimensional table.
-- @return  Table of table containing the current arp entries.
--          The following fields are defined for arp entry objects:
--          { "IP address", "HW address", "HW type", "Flags", "Mask", "Device" }
function net.arptable(callback)
    return _parse_delimited_table(io.lines("/proc/net/arp"), "%s%s+", callback)
end

--- Returns conntrack information
-- @return  Table with the currently tracked IP connections
function net.conntrack(callback)
    local connt = {}
    if fs.access("/proc/net/nf_conntrack", "r") then
        for line in io.lines("/proc/net/nf_conntrack") do
            line = line:match "^(.-( [^ =]+=).-)%2"
            local entry, flags = _parse_mixed_record(line, " +")
            if flags[6] ~= "TIME_WAIT" then
                entry.layer3 = flags[1]
                entry.layer4 = flags[3]
                for i=1, #entry do
                    entry[i] = nil
                end

                if callback then
                    callback(entry)
                else
                    connt[#connt+1] = entry
                end
            end
        end
    elseif fs.access("/proc/net/ip_conntrack", "r") then
        for line in io.lines("/proc/net/ip_conntrack") do
            line = line:match "^(.-( [^ =]+=).-)%2"
            local entry, flags = _parse_mixed_record(line, " +")
            if flags[4] ~= "TIME_WAIT" then
                entry.layer3 = "ipv4"
                entry.layer4 = flags[1]
                for i=1, #entry do
                    entry[i] = nil
                end

                if callback then
                    callback(entry)
                else
                    connt[#connt+1] = entry
                end
            end
        end
    else
        return nil
    end
    return connt
end

--- Determine the current IPv4 default route. If multiple default routes exist,
-- return the one with the lowest metric.
-- @return  Table with the properties of the current default route.
--          The following fields are defined:
--          { "dest", "gateway", "metric", "refcount", "usecount", "irtt",
--            "flags", "device" }
function net.defaultroute()
    local route

    net.routes(function(rt)
        if rt.dest:prefix() == 0 and (not route or route.metric > rt.metric) then
            route = rt
        end
    end)

    return route
end

--- Determine the current IPv6 default route. If multiple default routes exist,
-- return the one with the lowest metric.
-- @return  Table with the properties of the current default route.
--          The following fields are defined:
--          { "source", "dest", "nexthop", "metric", "refcount", "usecount",
--            "flags", "device" }
function net.defaultroute6()
    local route

    net.routes6(function(rt)
        if rt.dest:prefix() == 0 and rt.device ~= "lo" and
           (not route or route.metric > rt.metric)
        then
            route = rt
        end
    end)

    if not route then
        local global_unicast = luci.ip.IPv6("2000::/3")
        net.routes6(function(rt)
            if rt.dest:equal(global_unicast) and
               (not route or route.metric > rt.metric)
            then
                route = rt
            end
        end)
    end

    return route
end

--- Determine the names of available network interfaces.
-- @return  Table containing all current interface names
function net.devices()
    local devs = {}
    for k, v in ipairs(nixio.getifaddrs()) do
        if v.family == "packet" then
            devs[#devs+1] = v.name
        end
    end
    return devs
end


--- Return information about available network interfaces.
-- @return  Table containing all current interface names and their information
function net.deviceinfo()
    local devs = {}
    for k, v in ipairs(nixio.getifaddrs()) do
        if v.family == "packet" then
            local d = v.data
            d[1] = d.rx_bytes
            d[2] = d.rx_packets
            d[3] = d.rx_errors
            d[4] = d.rx_dropped
            d[5] = 0
            d[6] = 0
            d[7] = 0
            d[8] = d.multicast
            d[9] = d.tx_bytes
            d[10] = d.tx_packets
            d[11] = d.tx_errors
            d[12] = d.tx_dropped
            d[13] = 0
            d[14] = d.collisions
            d[15] = 0
            d[16] = 0
            devs[v.name] = d
        end
    end
    return devs
end


-- Determine the MAC address belonging to the given IP address.
-- @param ip    IPv4 address
-- @return      String containing the MAC address or nil if it cannot be found
function net.ip4mac(ip)
    local mac = nil
    net.arptable(function(e)
        if e["IP address"] == ip then
            mac = e["HW address"]
        end
    end)
    return mac
end

--- Returns the current kernel routing table entries.
-- @return  Table of tables with properties of the corresponding routes.
--          The following fields are defined for route entry tables:
--          { "dest", "gateway", "metric", "refcount", "usecount", "irtt",
--            "flags", "device" }
function net.routes(callback)
    local routes = { }

    for line in io.lines("/proc/net/route") do

        local dev, dst_ip, gateway, flags, refcnt, usecnt, metric,
              dst_mask, mtu, win, irtt = line:match(
            "([^%s]+)\t([A-F0-9]+)\t([A-F0-9]+)\t([A-F0-9]+)\t" ..
            "(%d+)\t(%d+)\t(%d+)\t([A-F0-9]+)\t(%d+)\t(%d+)\t(%d+)"
        )

        if dev then
            gateway  = luci.ip.Hex( gateway,  32, luci.ip.FAMILY_INET4 )
            dst_mask = luci.ip.Hex( dst_mask, 32, luci.ip.FAMILY_INET4 )
            dst_ip   = luci.ip.Hex(
                dst_ip, dst_mask:prefix(dst_mask), luci.ip.FAMILY_INET4
            )

            local rt = {
                dest     = dst_ip,
                gateway  = gateway,
                metric   = tonumber(metric),
                refcount = tonumber(refcnt),
                usecount = tonumber(usecnt),
                mtu      = tonumber(mtu),
                window   = tonumber(window),
                irtt     = tonumber(irtt),
                flags    = tonumber(flags, 16),
                device   = dev
            }

            if callback then
                callback(rt)
            else
                routes[#routes+1] = rt
            end
        end
    end

    return routes
end

--- Returns the current ipv6 kernel routing table entries.
-- @return  Table of tables with properties of the corresponding routes.
--          The following fields are defined for route entry tables:
--          { "source", "dest", "nexthop", "metric", "refcount", "usecount",
--            "flags", "device" }
function net.routes6(callback)
    if fs.access("/proc/net/ipv6_route", "r") then
        local routes = { }

        for line in io.lines("/proc/net/ipv6_route") do

            local dst_ip, dst_prefix, src_ip, src_prefix, nexthop,
                  metric, refcnt, usecnt, flags, dev = line:match(
                "([a-f0-9]+) ([a-f0-9]+) " ..
                "([a-f0-9]+) ([a-f0-9]+) " ..
                "([a-f0-9]+) ([a-f0-9]+) " ..
                "([a-f0-9]+) ([a-f0-9]+) " ..
                "([a-f0-9]+) +([^%s]+)"
            )

            src_ip = luci.ip.Hex(
                src_ip, tonumber(src_prefix, 16), luci.ip.FAMILY_INET6, false
            )

            dst_ip = luci.ip.Hex(
                dst_ip, tonumber(dst_prefix, 16), luci.ip.FAMILY_INET6, false
            )

            nexthop = luci.ip.Hex( nexthop, 128, luci.ip.FAMILY_INET6, false )

            local rt = {
                source   = src_ip,
                dest     = dst_ip,
                nexthop  = nexthop,
                metric   = tonumber(metric, 16),
                refcount = tonumber(refcnt, 16),
                usecount = tonumber(usecnt, 16),
                flags    = tonumber(flags, 16),
                device   = dev,

                -- lua number is too small for storing the metric
                -- add a metric_raw field with the original content
                metric_raw = metric
            }

            if callback then
                callback(rt)
            else
                routes[#routes+1] = rt
            end
        end

        return routes
    end
end

--- Tests whether the given host responds to ping probes.
-- @param host  String containing a hostname or IPv4 address
-- @return      Number containing 0 on success and >= 1 on error
function net.pingtest(host)
    return os.execute("ping -c1 '"..host:gsub("'", '').."' >/dev/null 2>&1")
end


--- LuCI system utilities / process related functions.
-- @class   module
-- @name    luci.sys.process
process = {}

--- Get the current process id.
-- @class function
-- @name  process.info
-- @return  Number containing the current pid
function process.info(key)
    local s = {uid = nixio.getuid(), gid = nixio.getgid()}
    return not key and s or s[key]
end

--- Retrieve information about currently running processes.
-- @return  Table containing process information
function process.list()
    local data = {}
    local k
    local ps = luci.util.execi("top -bn1")

    if not ps then
        return
    end

    while true do
        local line = ps()
        if not line then
            return
        end

        k = luci.util.split(luci.util.trim(line), "%s+", nil, true)
        if k[6] == "%VSZ" then
            k[6] = "%MEM"
        end
        if k[1] == "PID" then
            break
        end
    end

    for line in ps do
        local row = {}

        line = luci.util.trim(line)
        for i, value in ipairs(luci.util.split(line, "%s+", #k-1, true)) do
            row[k[i]] = value
        end

        local pid = tonumber(row[k[1]])
        if pid then
            data[pid] = row
        end
    end

    return data
end

--- Set the gid of a process identified by given pid.
-- @param gid   Number containing the Unix group id
-- @return      Boolean indicating successful operation
-- @return      String containing the error message if failed
-- @return      Number containing the error code if failed
function process.setgroup(gid)
    return nixio.setgid(gid)
end

--- Set the uid of a process identified by given pid.
-- @param uid   Number containing the Unix user id
-- @return      Boolean indicating successful operation
-- @return      String containing the error message if failed
-- @return      Number containing the error code if failed
function process.setuser(uid)
    return nixio.setuid(uid)
end

--- Send a signal to a process identified by given pid.
-- @class function
-- @name  process.signal
-- @param pid   Number containing the process id
-- @param sig   Signal to send (default: 15 [SIGTERM])
-- @return      Boolean indicating successful operation
-- @return      Number containing the error code if failed
process.signal = nixio.kill


--- LuCI system utilities / user related functions.
-- @class   module
-- @name    luci.sys.user
user = {}

--- Retrieve user informations for given uid.
-- @class       function
-- @name        getuser
-- @param uid   Number containing the Unix user id
-- @return      Table containing the following fields:
--              { "uid", "gid", "name", "passwd", "dir", "shell", "gecos" }
user.getuser = nixio.getpw

--- Retrieve the current user password hash.
-- @param username  String containing the username to retrieve the password for
-- @return          String containing the hash or nil if no password is set.
function user.getpasswd(username)
    local pwe = nixio.getsp and nixio.getsp(username) or nixio.getpw(username)
    local pwh = pwe and (pwe.pwdp or pwe.passwd)
    if not pwh or #pwh < 1 or pwh == "!" or pwh == "x" then
        return nil
    else
        return pwh
    end
end

--- Test whether given string matches the password of a given system user.
-- @param username  String containing the Unix user name
-- @param pass      String containing the password to compare
-- @return          Boolean indicating wheather the passwords are equal
function user.checkpasswd(username, pass)
    local pwh = user.getpasswd(username)
    if pwh and nixio.crypt(pass, pwh) ~= pwh then
        return false
    else
        return true
    end
end

--- Change the password of given user.
-- @param username  String containing the Unix user name
-- @param password  String containing the password to compare
-- @return          Number containing 0 on success and >= 1 on error
function user.setpasswd(username, password)
    if password then
        password = password:gsub("'", [['"'"']])
    end

    if username then
        username = username:gsub("'", [['"'"']])
    end

    return os.execute(
        "(echo '" .. password .. "'; sleep 1; echo '" .. password .. "') | " ..
        "passwd '" .. username .. "' >/dev/null 2>&1"
    )
end


--- LuCI system utilities / wifi related functions.
-- @class   module
-- @name    luci.sys.wifi
wifi = {}

--- Get wireless information for given interface.
-- @param ifname        String containing the interface name
-- @return              A wrapped iwinfo object instance
function wifi.getiwinfo(ifname)
    local stat, iwinfo = pcall(require, "iwinfo")

    if ifname then
        local c = 0
        local u = uci.cursor_state()
        local d, n = ifname:match("^(%w+)%.network(%d+)")
        if d and n then
            n = tonumber(n)
            u:foreach("wireless", "wifi-iface",
                function(s)
                    if s.device == d then
                        c = c + 1
                        if c == n then
                            ifname = s.ifname or s.device
                            return false
                        end
                    end
                end)
        elseif u:get("wireless", ifname) == "wifi-device" then
            u:foreach("wireless", "wifi-iface",
                function(s)
                    if s.device == ifname and s.ifname then
                        ifname = s.ifname
                        return false
                    end
                end)
        end

        local t = stat and iwinfo.type(ifname)
        local x = t and iwinfo[t] or { }
        return setmetatable({}, {
            __index = function(t, k)
                if k == "ifname" then
                    return ifname
                elseif x[k] then
                    return x[k](ifname)
                end
            end
        })
    end
end

--- Get iwconfig output for all wireless devices.
-- @return  Table of tables containing the iwconfing output for each wifi device
function wifi.getiwconfig()
    local cnt = luci.util.exec("PATH=/sbin:/usr/sbin iwconfig 2>/dev/null")
    local iwc = {}

    for i, l in pairs(luci.util.split(luci.util.trim(cnt), "\n\n")) do
        local k = l:match("^(.-) ")
        l = l:gsub("^(.-) +", "", 1)
        if k then
            local entry, flags = _parse_mixed_record(l)
            if entry then
                entry.flags = flags
            end
            iwc[k] = entry
        end
    end

    return iwc
end

--- Get iwlist scan output from all wireless devices.
-- @return  Table of tables contaiing all scan results
function wifi.iwscan(iface)
    local siface = iface or ""
    local cnt = luci.util.exec("iwlist "..siface.." scan 2>/dev/null")
    local iws = {}

    for i, l in pairs(luci.util.split(luci.util.trim(cnt), "\n\n")) do
        local k = l:match("^(.-) ")
        l = l:gsub("^[^\n]+", "", 1)
        l = luci.util.trim(l)
        if k then
            iws[k] = {}
            for j, c in pairs(luci.util.split(l, "\n          Cell")) do
                c = c:gsub("^(.-)- ", "", 1)
                c = luci.util.split(c, "\n", 7)
                c = table.concat(c, "\n", 1)
                local entry, flags = _parse_mixed_record(c)
                if entry then
                    entry.flags = flags
                end
                table.insert(iws[k], entry)
            end
        end
    end

    return iface and (iws[iface] or {}) or iws
end

--- Get available channels from given wireless iface.
-- @param iface Wireless interface (optional)
-- @return      Table of available channels
function wifi.channels(iface)
    local stat, iwinfo = pcall(require, "iwinfo")
    local cns

    if stat then
        local t = iwinfo.type(iface or "")
        if iface and t and iwinfo[t] then
            cns = iwinfo[t].freqlist(iface)
        end
    end

    if not cns or #cns == 0 then
        cns = {
            {channel =  1, mhz = 2412},
            {channel =  2, mhz = 2417},
            {channel =  3, mhz = 2422},
            {channel =  4, mhz = 2427},
            {channel =  5, mhz = 2432},
            {channel =  6, mhz = 2437},
            {channel =  7, mhz = 2442},
            {channel =  8, mhz = 2447},
            {channel =  9, mhz = 2452},
            {channel = 10, mhz = 2457},
            {channel = 11, mhz = 2462}
        }
    end

    return cns
end


--- LuCI system utilities / init related functions.
-- @class   module
-- @name    luci.sys.init
init = {}
init.dir = "/etc/init.d/"

--- Get the names of all installed init scripts
-- @return  Table containing the names of all inistalled init scripts
function init.names()
    local names = { }
    for name in fs.glob(init.dir.."*") do
        names[#names+1] = fs.basename(name)
    end
    return names
end

--- Get the index of he given init script
-- @param name  Name of the init script
-- @return      Numeric index value
function init.index(name)
    if fs.access(init.dir..name) then
        return call("env -i sh -c 'source %s%s enabled; exit ${START:-255}' >/dev/null"
            %{ init.dir, name })
    end
end

local function init_action(action, name)
    if fs.access(init.dir..name) then
        return call("env -i %s%s %s >/dev/null" %{ init.dir, name, action })
    end
end

--- Test whether the given init script is enabled
-- @param name  Name of the init script
-- @return      Boolean indicating whether init is enabled
function init.enabled(name)
    return (init_action("enabled", name) == 0)
end

--- Enable the given init script
-- @param name  Name of the init script
-- @return      Boolean indicating success
function init.enable(name)
    return (init_action("enable", name) == 1)
end

--- Disable the given init script
-- @param name  Name of the init script
-- @return      Boolean indicating success
function init.disable(name)
    return (init_action("disable", name) == 0)
end

--- Start the given init script
-- @param name  Name of the init script
-- @return      Boolean indicating success
function init.start(name)
    return (init_action("start", name) == 0)
end

--- Stop the given init script
-- @param name  Name of the init script
-- @return      Boolean indicating success
function init.stop(name)
    return (init_action("stop", name) == 0)
end


-- Internal functions

function _parse_delimited_table(iter, delimiter, callback)
    delimiter = delimiter or "%s+"

    local data  = {}
    local trim  = luci.util.trim
    local split = luci.util.split

    local keys = split(trim(iter()), delimiter, nil, true)
    for i, j in pairs(keys) do
        keys[i] = trim(keys[i])
    end

    for line in iter do
        local row = {}
        line = trim(line)
        if #line > 0 then
            for i, j in pairs(split(line, delimiter, nil, true)) do
                if keys[i] then
                    row[keys[i]] = j
                end
            end
        end

        if callback then
            callback(row)
        else
            data[#data+1] = row
        end
    end

    return data
end

function _parse_mixed_record(cnt, delimiter)
    delimiter = delimiter or "  "
    local data = {}
    local flags = {}

    for i, l in pairs(luci.util.split(luci.util.trim(cnt), "\n")) do
        for j, f in pairs(luci.util.split(luci.util.trim(l), delimiter, nil, true)) do
            local k, x, v = f:match('([^%s][^:=]*) *([:=]*) *"*([^\n"]*)"*')

            if k then
                if x == "" then
                    table.insert(flags, k)
                else
                    data[k] = v
                end
            end
        end
    end

    return data, flags
end