mirror of https://github.com/asterisk/asterisk
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
471 lines
20 KiB
471 lines
20 KiB
|
|
* Application SMS
|
|
|
|
The SMS module for Asterisk was developed by Adrian Kennard, and is an
|
|
implementation of the ETSI specification for landline SMS, ETSI ES 201
|
|
912, which is available from www.etsi.org. Landline SMS is starting to
|
|
be available in various parts of Europe, and is available from BT in
|
|
the UK. However, Asterisk would allow gateways to be created in other
|
|
locations such as the US, and use of SMS capable phones such as the
|
|
Magic Messenger. SMS works using analogue or ISDN lines.
|
|
|
|
Background
|
|
|
|
Short Message Service (SMS), or texting is very popular between mobile
|
|
phones. A message can be sent between two phones, and normally
|
|
contains 160 characters. There are ways in which various types of data
|
|
can be encoded in a text message such as ring tones, and small
|
|
graphic, etc. Text messaging is being used for voting and
|
|
competitions, and also SPAM...
|
|
Sending a message involves the mobile phone contacting a message
|
|
centre (SMSC) and passing the message to it. The message centre then
|
|
contacts the destination mobile to deliver the message. The SMSC is
|
|
responsible for storing the message and trying to send it until the
|
|
destination mobile is available, or a timeout.
|
|
Landline SMS works in basically the same way. You would normally have
|
|
a suitable text capable landline phone, or a separate texting box such
|
|
as a Magic Messenger on your phone line. This sends a message to a
|
|
message centre your telco provides by making a normal call and sending
|
|
the data using 1200 Baud FSK signaling according to the ETSI spec. To
|
|
receive a message the message centre calls the line with a specific
|
|
calling number, and the text capable phone answers the call and
|
|
receives the data using 1200 Baud FSK signaling. This works
|
|
particularly well in the UK as the calling line identity is sent
|
|
before the first ring, so no phones in the house would ring when a
|
|
message arrives.
|
|
|
|
Typical use with Asterisk
|
|
|
|
Sending messages from an Asterisk box can be used for a variety of
|
|
reasons, including notification from any monitoring systems, email
|
|
subject lines, etc.
|
|
Receiving messages to an Asterisk box is typically used just to email
|
|
the messages to someone appropriate - we email and texts that are
|
|
received to our direct numbers to the appropriate person. Received
|
|
messages could also be used to control applications, manage
|
|
competitions, votes, post items to IRC, anything.
|
|
Using a terminal such as a magic messenger, an Asterisk box could ask
|
|
as a message centre sending messages to the terminal, which will beep
|
|
and pop up the message (and remember 100 or so messages in its
|
|
memory).
|
|
|
|
Terminology
|
|
|
|
SMS
|
|
Short Message Service
|
|
i.e. text messages
|
|
SMSC
|
|
Short Message Service Centre
|
|
The system responsible for storing and forwarding messages
|
|
MO
|
|
Mobile Originated
|
|
A message on its way from a mobile or landline device to the SMSC
|
|
MT
|
|
Mobile Terminated
|
|
A message on its way from the SMSC to the mobile or landline device
|
|
RX
|
|
Receive
|
|
A message coming in to the Asterisk box
|
|
TX
|
|
Transmit
|
|
A message going out of the Asterisk box
|
|
|
|
Sub address
|
|
|
|
When sending a message to a landline, you simply send to the landline
|
|
number. In the UK, all of the mobile operators (bar one) understand
|
|
sending messages to landlines and pass the messages to the BTText
|
|
system for delivery to the landline.
|
|
The specification for landline SMS allows for the possibility of more
|
|
than one device on a single landline. These can be configured with Sub
|
|
addresses which are a single digit. To send a message to a specific
|
|
device the message is sent to the landline number with an extra digit
|
|
appended to the end. The telco can define a default sub address (9 in
|
|
the UK) which is used when the extra digit is not appended to the end.
|
|
When the call comes in, part of the calling line ID is the sub
|
|
address, so that only one device on the line answers the call and
|
|
receives the message.
|
|
Sub addresses also work for outgoing messages. Part of the number
|
|
called by the device to send a message is its sub address. Sending
|
|
from the default sub address (9 in the UK) means the message is
|
|
delivered with the sender being the normal landline number. Sending
|
|
from any other sub address makes the sender the landline number with
|
|
an extra digit on the end.
|
|
Using Asterisk, you can make use of the sub addresses for sending and
|
|
receiving messages. Using DDI (DID, i.e. multiple numbers on the line
|
|
on ISDN) you can also make use of many different numbers for SMS.
|
|
|
|
Build / installation
|
|
|
|
app_sms.c is included in the Asterisk source apps directory and is
|
|
included in the object list (app_sms.so) in apps/Makefile.
|
|
smsq.c is a stand alone helper application which is used to send SMSs
|
|
from the command line. It uses the popt library. A line for your make
|
|
file is:-
|
|
smsq: smsq.c
|
|
cc -O -o smsq smsq.c -lpopt
|
|
|
|
extensions.conf
|
|
|
|
The following contexts are recommended.
|
|
; Mobile Terminated, RX. This is used when an incoming call from the SMS arrive
|
|
s, with the queue (called number and sub address) in ${EXTEN}
|
|
; Running an app after receipt of the text allows the app to find all messages
|
|
in the queue and handle them, e.g. email them.
|
|
; The app may be something like smsq --process=somecommand --queue=${EXTEN}
|
|
to run a command for each received message
|
|
; See below for usage
|
|
[smsmtrx]
|
|
exten = _X.,1, SMS(${EXTEN}|a)
|
|
exten = _X.,2,System("someapptohandleincomingsms ${EXTEN}")
|
|
exten = _X.,3,Hangup
|
|
; Mobile originated, RX. This is receiving a message from a device, e.g. a Magi
|
|
c Messenger on a sip extension
|
|
; Running an app after receipt of the text allows the app to find all messages
|
|
in the queue and handle then, e.g. sending them to the public SMSC
|
|
; The app may be something like smsq --process=somecommand --queue=${EXTEN}
|
|
to run a command for each received message
|
|
; See below for example usage
|
|
[smsmorx]
|
|
exten = _X.,1, SMS(${EXTEN}|sa)
|
|
exten = _X.,2,System("someapptohandlelocalsms ${EXTEN}")
|
|
exten = _X.,3,Hangup
|
|
|
|
smsmtrx is normally accessed by an incoming call from the SMSC. In the
|
|
UK this call is from a CLI of 080058752X0 where X is the sub address.
|
|
As such a typical usage in the extensions.conf at the point of
|
|
handling an incoming call is:-
|
|
exten = _X./8005875290,1,Goto(smsmtrx,${EXTEN},1)
|
|
exten = _X./_80058752[0-8]0,1,Goto(smsmtrx,${EXTEN}-${CALLERIDNUM:8:1},1)
|
|
|
|
Alternatively, if you have the correct national prefix on incoming
|
|
CLI, e.g. using zaphfc, you might use:-
|
|
exten = _X./08005875290,1,Goto(smsmtrx,${EXTEN},1)
|
|
exten = _X./_080058752[0-8]0,1,Goto(smsmtrx,${EXTEN}-${CALLERIDNUM:9:1},1)
|
|
|
|
smsmorx is normally accessed by a call from a local sip device
|
|
connected to a Magic Messenger. It could however by that you are
|
|
operating Asterisk as a message centre for calls from outside. Either
|
|
way, you look at the called number and goto smsmorx. In the UK, the
|
|
SMSC number that would be dialed is 1709400X where X is the caller sub
|
|
address. As such typical usage in extension.config at the point of
|
|
handling a call from a sip phone is:-
|
|
exten = 17094009,1,Goto(smsmorx,${CALLERIDNUM},1)
|
|
exten = _1709400[0-8],1,Goto(smsmorx,${CALLERIDNUM}-{EXTEN:7:1},1)
|
|
|
|
Using smsq
|
|
|
|
smsq is a simple helper application designed to make it easy to send
|
|
messages from a command line. it is intended to run on the Asterisk
|
|
box and have direct access to the queue directories for SMS and for
|
|
Asterisk.
|
|
In its simplest form you can send an SMS by a command such as
|
|
smsq 0123456789 This is a test to 0123456789
|
|
This would create a queue file for a mobile originated TX message in
|
|
queue 0 to send the text "This is a test to 0123456789" to 0123456789.
|
|
It would then place a file in the /var/spool/asterisk/outgoing
|
|
directory to initiate a call to 17094009 (the default message centre
|
|
in smsq) attached to application SMS with argument of the queue name
|
|
(0).
|
|
Normally smsq will queue a message ready to send, and will then create
|
|
a file in the Asterisk outgoing directory causing Asterisk to actually
|
|
connect to the message centre or device and actually send the pending
|
|
message(s).
|
|
Using --process, smsq can however be used on received queues to run a
|
|
command for each file (matching the queue if specified) with various
|
|
environment variables set based on the message (see below);
|
|
smsq options:-
|
|
|
|
--help
|
|
Show help text
|
|
--usage
|
|
Show usage
|
|
--queue
|
|
-q
|
|
Specify a specific queue
|
|
In no specified, messages are queued under queue "0"
|
|
--da
|
|
-d
|
|
Specify destination address
|
|
--oa
|
|
-o
|
|
Specify originating address
|
|
This also implies that we are generating a mobile terminated message
|
|
--ud
|
|
-m
|
|
Specify the actual message
|
|
--ud-file
|
|
-f
|
|
Specify a file to be read for the context of the message
|
|
A blank filename (e.g. --ud-file= on its own) means read stdin. Very
|
|
useful when using via ssh where command line parsing could mess up the
|
|
message.
|
|
--mt
|
|
-t
|
|
Mobile terminated message to be generated
|
|
--mo
|
|
Mobile originated message to be generated
|
|
Default
|
|
--tx
|
|
Transmit message
|
|
Default
|
|
--rx
|
|
-r
|
|
Generate a message in the receive queue
|
|
--UTF-8
|
|
Treat the file as UTF-8 encoded (default)
|
|
--UCS-1
|
|
Treat the file as raw 8 bit UCS-1 data, not UTF-8 encoded
|
|
--UCS-2
|
|
Treat the file as raw 16 bit bigendian USC-2 data
|
|
--process
|
|
Specific a command to process for each file in the queue
|
|
Implies --rx and --mt if not otherwise specified.
|
|
Sets environment variables for every possible variable, and also ud,
|
|
ud8 (USC-1 hex), and ud16 (USC-2 hex) for each call. Removes files.
|
|
--motx-channel
|
|
Specify the channel for motx calls
|
|
May contain X to use sub address based on queue name or may be full
|
|
number
|
|
Default is Local/1709400X
|
|
--motx-callerid
|
|
Specify the caller ID for motx calls
|
|
The default is the queue name without -X suffix
|
|
--motx-wait
|
|
Wait time for motx call
|
|
Default 10
|
|
--motx-delay
|
|
Retry time for motx call
|
|
Default 1
|
|
--motx-retries
|
|
Retries for motx call
|
|
Default 10
|
|
--mttx-channel
|
|
Specify the channel for mttx calls
|
|
Default is Local/ and the queue name without -X suffix
|
|
--mtttx-callerid
|
|
Specify the callerid for mttx calls
|
|
May include X to use sub address based on queue name or may be full
|
|
number
|
|
Default is 080058752X0
|
|
--mttx-wait
|
|
Wait time for mttx call
|
|
Default 10
|
|
--mttx-delay
|
|
Retry time for mttx call
|
|
Default 30
|
|
--mttx-retries
|
|
Retries for mttx call
|
|
Default 100
|
|
--default-sub-address
|
|
The default sub address assumed (e.g. for X in CLI and dialled numbers
|
|
as above) when none added (-X) to queue
|
|
Default 9
|
|
--no-dial
|
|
-x
|
|
Create queue, but do not dial to send message
|
|
--no-wait
|
|
Do not wait if a call appears to be in progress
|
|
This could have a small window where a mesdsage is queued but not
|
|
sent, so regular calls to smsq should be done to pick up any missed
|
|
messages
|
|
--concurrent
|
|
How many concurrent calls to allow (per queue), default 1
|
|
--mr
|
|
-n
|
|
Message reference
|
|
--pid
|
|
-p
|
|
Protocol ID
|
|
--dcs
|
|
Data coding scheme
|
|
--udh
|
|
Specific hex string of user data header specified (not including the
|
|
initial length byte)
|
|
May be a blank string to indicate header is included in the user data
|
|
already but user data header indication to be set.
|
|
--srr
|
|
Status report requested
|
|
--rp
|
|
Return path requested
|
|
--vp
|
|
Specify validity period (seconds)
|
|
--scts
|
|
Specify timestamp (YYYY-MM-DDTHH:MM:SS)
|
|
--spool-dir
|
|
Spool dir (in which sms and outgoing are found)
|
|
Default /var/spool/asterisk
|
|
|
|
Other arguments starting '-' or '--' are invalid and will cause an
|
|
error. Any trailing arguments are processed as follows:-
|
|
* If the message is mobile originating and no destination address
|
|
has been specified, then the first argument is assumed to be a
|
|
destination address
|
|
* If the message is mobile terminating and no destination address
|
|
has been specified, then the first argument is assumed to be the
|
|
queue name
|
|
* If there is no user data, or user data file specified, then any
|
|
following arguments are assumed to be the message, which are
|
|
concatenated.
|
|
* If no user data is specified, then no message is sent. However,
|
|
unless --no-dial is specified, smsq checks for pending messages
|
|
and generates an outgoing anyway
|
|
|
|
Note that when smsq attempts to make a file in
|
|
/var/spool/asterisk/outgoing, it checks if there is already a call
|
|
queued for that queue. It will try several filenames, up to the
|
|
--concorrent setting. If these files exists, then this means Asterisk
|
|
is already queued to send all messages for that queue, and so Asterisk
|
|
should pick up the message just queued. However, this alone could
|
|
create a race condition, so if the files exist then smsq will wait up
|
|
to 3 seconds to confirm it still exists or if the queued messages have
|
|
been sent already. The --no-wait turns off this behaviour. Basically,
|
|
this means that if you have a lot of messages to send all at once,
|
|
Asterisk will not make unlimited concurrent calls to the same message
|
|
centre or device for the same queue. This is because it is generally
|
|
more efficient to make one call and send all of the messages one after
|
|
the other.
|
|
smsq can be used with no arguments, or with a queue name only, and it
|
|
will check for any pending messages and cause an outgoing if there are
|
|
any. It only sets up one outgoing call at a time based on the first
|
|
queued message it finds. A outgoing call will normally send all queued
|
|
messages for that queue. One way to use smsq would be to run with no
|
|
queue name (so any queue) every minute or every few seconds to send
|
|
pending message. This is not normally necessary unless --no-dial is
|
|
selected. Note that smsq does only check motx or mttx depending on the
|
|
options selected, so it would need to be called twice as a general
|
|
check.
|
|
UTF-8 is used to parse command line arguments for user data, and is
|
|
the default when reading a file. If an invalid UTF-8 sequence is
|
|
found, it is treated as UCS-1 data (i.e, as is).
|
|
The --process option causes smsq to scan the specified queue (default
|
|
is mtrx) for messages (matching the queue specified, or any if queue
|
|
not specified) and run a command and delete the file. The command is
|
|
run with a number of environment variables set as follows. Note that
|
|
these are unset if not needed and not just taken from the calling
|
|
environment. This allows simple processing of incoming messages
|
|
|
|
$queue
|
|
Set if a queue specified
|
|
$?srr
|
|
srr is set (to blank) if srr defined and has value 1.
|
|
$?rp
|
|
rp is set (to blank) if rp defined and has value 1.
|
|
$ud
|
|
User data, UTF-8 encoding, including any control characters, but with
|
|
nulls stripped out
|
|
Useful for the content of emails, for example, as it includes any
|
|
newlines, etc.
|
|
$ude
|
|
User data, escaped UTF-8, including all characters, but control
|
|
characters \n, \r, \t, \f, \xxx and \ is escaped as \\
|
|
Useful fGuaranteed one line printable text, so useful in Subject lines
|
|
of emails, etc
|
|
$ud8
|
|
Hex UCS-1 coding of user data (2 hex digits per character)
|
|
Present only if all user data is in range U+0000 to U+00FF
|
|
$ud16
|
|
Hex UCS-2 coding of user data (4 hex digits per chartacter)
|
|
other
|
|
Other fields set using their field name, e.g. mr, pid, dcs, etc. udh
|
|
is a hex byte string
|
|
|
|
File formats
|
|
|
|
By default all queues are held in a director /var/spool/asterisk/sms.
|
|
Within this directory are sub directories mtrx, mttx, morx, motx which
|
|
hold the received messages and the messages ready to send. Also,
|
|
/var/log/asterisk/sms is a log file of all messages handled.
|
|
The file name in each queue directory starts with the queue parameter
|
|
to SMS which is normally the CLI used for an outgoing message or the
|
|
called number on an incoming message, and may have -X (X being sub
|
|
address) appended. If no queue ID is known, then 0 is used by smsq by
|
|
default. After this is a dot, and then any text. Files are scanned for
|
|
matching queue ID and a dot at the start. This means temporary files
|
|
being created can be given a different name not starting with a queue
|
|
(we recommend a . on the start of the file name for temp files).
|
|
Files in these queues are in the form of a simple text file where each
|
|
line starts with a keyword and an = and then data. udh and ud have
|
|
options for hex encoding, see below.
|
|
UTF-8. The user data (ud) field is treated as being UTF-8 encoded
|
|
unless the DCS is specified indicating 8 bit formart. If 8 bit format
|
|
is specified then the user data is sent as is.
|
|
The keywords are as follows:-
|
|
|
|
oa Originating address
|
|
The phone number from which the message came
|
|
Present on mobile terminated messages and is the CLI for morx messages
|
|
da
|
|
Destination Address
|
|
The phone number to which the message is sent
|
|
Present on mobile originated messages
|
|
scts
|
|
The service centre time stamp
|
|
Format YYYY-MM-DDTHH:MM:SS
|
|
Present on mobile terminated messages
|
|
pid
|
|
One byte decimal protocol ID
|
|
See GSM specs for more details
|
|
Normally 0 or absent
|
|
dcs
|
|
One byte decimal data coding scheme
|
|
If omitted, a sensible default is used (see below)
|
|
See GSM specs for more details
|
|
mr
|
|
One byte decimal message reference
|
|
Present on mobile originated messages, added by default if absent
|
|
srr
|
|
0 or 1 for status report request
|
|
Does not work in UK yet, not implemented in app_sms yet
|
|
rp
|
|
0 or 1 return path
|
|
See GSM specs for details
|
|
vp
|
|
Validity period in seconds
|
|
Does not work in UK yet
|
|
udh
|
|
Hex string of user data header prepended to the SMS contents,
|
|
excluding initial length byte.
|
|
Consistent with ud, this is specified as udh# rather than udh=
|
|
If blank, this means that the udhi flag will be set but any user data
|
|
header must be in the ud field
|
|
ud
|
|
User data, may be text, or hex, see below
|
|
|
|
udh is specified as as udh# followed by hex (2 hex digits per byte).
|
|
If present, then the user data header indicator bit is set, and the
|
|
length plus the user data header is added to the start of the user
|
|
data, with padding if necessary (to septet boundary in 7 bit format).
|
|
User data can hold an USC character codes U+0000 to U+FFFF. Any other
|
|
characters are coded as U+FEFF
|
|
ud can be specified as ud= followed by UTF-8 encoded text if it
|
|
contains no control characters, i.e. only (U+0020 to U+FFFF). Any
|
|
invalid UTF-8 sequences are treated as is (U+0080-U+00FF).
|
|
ud can also be specified as ud# followed by hex (2 hex digits per
|
|
byte) containing characters U+0000 to U+00FF only.
|
|
ud can also be specified as ud## followed by hex (4 hex digits per
|
|
byte) containing UCS-2 characters.
|
|
When written by app_sms (e.g. incoming messages), the file is written
|
|
with ud= if it can be (no control characters). If it cannot, the a
|
|
comment line ;ud= is used to show the user data for human readability
|
|
and ud# or ud## is used.
|
|
|
|
Delivery reports
|
|
|
|
The SMS specification allows for delivery reports. These are requested
|
|
using the srr bit. However, as these do not work in the UK yet they
|
|
are not fully implemented in this application. If anyone has a telco
|
|
that does implement these, please let me know. BT in the UK have a non
|
|
standard way to do this by starting the message with *0#, and so this
|
|
application may have a UK specific bodge in the near future to handle
|
|
these.
|
|
The main changes that are proposed for delivery report handling are :-
|
|
* New queues for sent messages, one file for each destination
|
|
address and message reference.
|
|
* New field in message format, user reference, allowing applications
|
|
to tie up their original message with a report.
|
|
* Handling of the delivery confirmation/rejection and connecting to
|
|
the outgoing message - the received message file would then have
|
|
fields for the original outgoing message and user reference
|
|
allowing applications to handle confirmations better.
|