Re: Unable to decode PDU for SMS-STATUS-REPORT

[Denis Kenzior <denkenz@gmail.com>]

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Hi Audric,

On 06/25/2012 11:10 AM, Audric Schiltknecht wrote:
> Hi guys.
>
> I'm having troubles with delivery reports.
>
> When I send a message with the property "UseDeliveryReports" set to "true",
> I can get the delivery report from the GSM modem, but ofono is unable to
> decode it:
>
> ofonod[677]: SMS: < \r\n+CDS:
> 32\r\n07913386094000F006DB0A810011223344216052714081802160527140228000\r\n
> ofonod[677]: drivers/atmodem/sms.c:at_cds_notify() Got new Status-Report
> PDU via CDS:
> 07913386094000F006DB0A810011223344216052714081802160527140228000, 32
> ofonod[677]: src/sms.c:ofono_sms_status_notify() len 32 tpdu len 32
> ofonod[677]: Unable to decode PDU
>
> The PDU is valid, since I can decode it using some online tool.
>
> It seems that sms_decode does not correctly handle the SMSCC part
> (913386094000F0),
> and tries to decode it as the sender address, which obviously fails.
>

Likely it is because your modem is being stupid.  3GPP 27.005 states:

<length> integer type value indicating in the text mode (+CMGF=1) the 
length of the message body <data> > (or <cdata>) in characters; or in 
PDU mode (+CMGF=0), the length of the actual TP data unit in octets 
(i.e. the RP layer SMSC address octets are not counted in the length)

So in the case above it should be reporting the length of the payload, 
not the length of the entire hex string.

See if the PDU is decoded successfully by setting tpdu_len to the 
appropriate value.

Regards,
-Denis