Don't update MK, we still need the original for storing new fast reauth IDs

diff --git a/src/lib/eap_aka_sim/crypto.c b/src/lib/eap_aka_sim/crypto.c
index 2b851e718e0052c6c38bc645730ea180b587a9c1..4a283b3872c295ab7ac7de601d3f32c752c1ac55 100644 (file)
--- a/src/lib/eap_aka_sim/crypto.c
+++ b/src/lib/eap_aka_sim/crypto.c
@@ -1132,7 +1132,7 @@ int fr_aka_sim_crypto_umts_kdf_1_reauth(fr_aka_sim_keys_t *keys)
 {
 #define KDF_1_S_REAUTH_STATIC  "EAP-AKA' re-auth"
        uint8_t s[(sizeof(KDF_1_S_REAUTH_STATIC) - 1) + AKA_SIM_MAX_STRING_LENGTH + sizeof(uint16_t) + AKA_SIM_NONCE_S_SIZE];
-
+       uint8_t         mk[AKA_PRIME_MK_SIZE];
        fr_dbuff_t      dbuff;
 
        if (!fr_cond_assert(((sizeof(KDF_1_S_REAUTH_STATIC) - 1) +
@@ -1189,13 +1189,17 @@ int fr_aka_sim_crypto_umts_kdf_1_reauth(fr_aka_sim_keys_t *keys)
 
        /*
         *      Feed into PRF
+        *
+        *      Note, we don't update the mk in the keys structure
+        *      as the original MK needs to be written into session
+        *      store, it doesn't change between re-authentication
+        *      rounds.
         */
-       keys->mk_len = AKA_PRIME_MK_SIZE;
-       if (aka_prime_prf(keys->mk, keys->mk_len, keys->k_re, sizeof(keys->k_re),
+       if (aka_prime_prf(mk, sizeof(mk), keys->k_re, sizeof(keys->k_re),
                          fr_dbuff_start(&dbuff), fr_dbuff_used(&dbuff)) < 0) return -1;
-       FR_PROTO_HEX_DUMP(keys->mk, keys->mk_len, "mk");
+       FR_PROTO_HEX_DUMP(mk, sizeof(mk), "mk");
 
-       fr_dbuff_init(&dbuff, keys->mk, keys->mk_len);                          /* dbuff now points to mk */
+       fr_dbuff_init(&dbuff, mk, sizeof(mk));                                  /* dbuff now points to mk */
 
        fr_dbuff_out_memcpy(keys->msk, &dbuff, sizeof(keys->msk));              /* 64 bytes for msk */
        FR_PROTO_HEX_DUMP(keys->msk, sizeof(keys->msk), "K_msk");