add osmo_auth_c3() (separate from gsm_milenage())
To send a Ciphering Mode Command, we may need to derive a Kc from UMTS AKA
tokens. gsm_milenage() derives Kc from 3G tokens, but also derives an SRES.
For SRES, it requires an OPC, which may need to be derived from OP first. All
we need is a Kc, so we could feed a zero OPC ... but to simplify the function
call for cases where just a Kc is required, separate the c3 function out from
gsm_milenage(), as osmo_auth_c3(). Obviously call osmo_auth_c3() from
gsm_milenage() (meaning that osmo-hlr's 55.205 derived auc tests still cover
exactly that implementation).
Prepares: If04e405426c55a81341747a9b450a69188525d5c (osmo-msc)
Related: OS#2745
Change-Id: I85a1d6ae95ad9e5ce9524ef7fc06414848afc2aa
diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index 6e6638a..d915234 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -340,6 +340,7 @@
osmo_auth_load;
osmo_auth_register;
osmo_auth_supported;
+osmo_auth_c3;
osmo_sub_auth_type_names;
osmo_rsl2sitype;