Revision 04ff01ef
Added by osmith about 4 years ago
| docs/imsi-pseudo-spec.adoc | ||
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6.2). When an SMS from the HLR/HSS in the structure of <<sms-structure>> arrives, |
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the applet must verify that the SMS is not outdated by comparing `imsi_pseudo_i` |
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from the SMS with the last `imsi_pseudo_i` that was used when changing the IMSI |
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(initially 1 as in <<hlr-imsi-pseudo-i>>). The new value must be higher, |
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otherwise the SMS should not be processed further. |
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(initially 1 as in <<hlr-imsi-pseudo-i>>). The new value must be higher. The |
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SIM applet must also verify, that the pseudonymous IMSI arriving in the SMS is |
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different from the currently active IMSI. If any of the checks fail, the SMS |
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must not be processed further. |
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The SIM applet registers a timer with `min_sleep_time` from the SMS. When the |
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timer triggers, EF~IMSI~ of the SIM/USIM is overwritten with the new pseudonymous |
Also available in: Unified diff
spec: SIM applet: verify: next IMSI is different
Suggested by ROS, so it would not be possible for the HLR to send the
same pseudonymous IMSI with an increased counter.
Seems like a good idea to me, if there was a bug in the HLR and it would
send the same pseudo IMSI for that reason, the SIM would not reset the
imsi_pseudo_lu counter.