Auth: Import milenage implementation from hostap (Jouni Malinen)
... and add integration into the osmo_auth core.
diff --git a/src/gsm/auth_milenage.c b/src/gsm/auth_milenage.c
new file mode 100644
index 0000000..2630350
--- /dev/null
+++ b/src/gsm/auth_milenage.c
@@ -0,0 +1,110 @@
+/* GSM/GPRS/3G authentication core infrastructure */
+
+/* (C) 2011 by Harald Welte <laforge@gnumonks.org>
+ *
+ * All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include <osmocom/crypt/auth.h>
+#include "milenage/common.h"
+#include "milenage/milenage.h"
+
+static void sqn_u64_to_48bit(uint8_t *sqn, const uint64_t sqn64)
+{
+ sqn[5] = (sqn64 >> 0) & 0xff;
+ sqn[4] = (sqn64 >> 8) & 0xff;
+ sqn[3] = (sqn64 >> 16) & 0xff;
+ sqn[2] = (sqn64 >> 24) & 0xff;
+ sqn[1] = (sqn64 >> 32) & 0xff;
+ sqn[0] = (sqn64 >> 40) & 0xff;
+}
+
+static uint64_t sqn_48bit_to_u64(const uint8_t *sqn)
+{
+ uint64_t sqn64;
+
+ sqn64 = sqn[0];
+ sqn64 <<= 8;
+ sqn64 |= sqn[1];
+ sqn64 <<= 8;
+ sqn64 |= sqn[2];
+ sqn64 <<= 8;
+ sqn64 |= sqn[3];
+ sqn64 <<= 8;
+ sqn64 |= sqn[4];
+ sqn64 <<= 8;
+ sqn64 |= sqn[5];
+
+ return sqn64;
+}
+
+
+static int milenage_gen_vec(struct osmo_auth_vector *vec,
+ struct osmo_sub_auth_data *aud,
+ const uint8_t *_rand)
+{
+ size_t res_len = sizeof(vec->res);
+ uint8_t sqn[6];
+ int rc;
+
+ sqn_u64_to_48bit(sqn, aud->umts.sqn);
+ milenage_generate(aud->umts.opc, aud->umts.amf, aud->umts.k,
+ sqn, _rand,
+ vec->autn, vec->ik, vec->ck, vec->res, &res_len);
+ vec->res_len = res_len;
+ rc = gsm_milenage(aud->umts.opc, aud->umts.k, _rand, vec->sres, vec->kc);
+ if (rc < 0)
+ return rc;
+
+ vec->auth_types = OSMO_AUTH_TYPE_UMTS | OSMO_AUTH_TYPE_GSM;
+ memcpy(vec->rand, _rand, sizeof(vec->rand));
+ aud->umts.sqn++;
+
+ return 0;
+}
+
+static int milenage_gen_vec_auts(struct osmo_auth_vector *vec,
+ struct osmo_sub_auth_data *aud,
+ const uint8_t *auts, const uint8_t *rand_auts,
+ const uint8_t *_rand)
+{
+ uint8_t sqn_out[6];
+ int rc;
+
+ rc = milenage_auts(aud->umts.opc, aud->umts.k,
+ rand_auts, auts, sqn_out);
+ if (rc < 0)
+ return rc;
+
+ aud->umts.sqn = sqn_48bit_to_u64(sqn_out) + 1;
+
+ return milenage_gen_vec(vec, aud, _rand);
+}
+
+static struct osmo_auth_impl milenage_alg = {
+ .algo = OSMO_AUTH_ALG_MILENAGE,
+ .name = "MILENAGE (libosmogsm built-in)",
+ .priority = 1000,
+ .gen_vec = &milenage_gen_vec,
+ .gen_vec_auts = &milenage_gen_vec_auts,
+};
+
+static __attribute__((constructor)) void on_dso_load_milenage(void)
+{
+ osmo_auth_register(&milenage_alg);
+}