diff --git a/openbsc/include/openbsc/gprs_gsup_messages.h b/openbsc/include/openbsc/gprs_gsup_messages.h
index 8cbc809..66a75a8 100644
--- a/openbsc/include/openbsc/gprs_gsup_messages.h
+++ b/openbsc/include/openbsc/gprs_gsup_messages.h
@@ -104,8 +104,8 @@
 	enum gprs_gsup_cancel_type	cancel_type;
 	int				pdp_info_compl;
 	int				freeze_ptmsi;
-	struct gsm_auth_tuple		auth_tuples[GPRS_GSUP_MAX_NUM_AUTH_INFO];
-	size_t				num_auth_tuples;
+	struct osmo_auth_vector		auth_vectors[GPRS_GSUP_MAX_NUM_AUTH_INFO];
+	size_t				num_auth_vectors;
 	struct gprs_gsup_pdp_info	pdp_infos[GPRS_GSUP_MAX_NUM_PDP_INFO];
 	size_t				num_pdp_infos;
 	const uint8_t			*msisdn_enc;
diff --git a/openbsc/include/openbsc/gsm_data.h b/openbsc/include/openbsc/gsm_data.h
index 6d7aba3..f229e74 100644
--- a/openbsc/include/openbsc/gsm_data.h
+++ b/openbsc/include/openbsc/gsm_data.h
@@ -5,6 +5,7 @@
 
 #include <osmocom/core/timer.h>
 #include <osmocom/core/select.h>
+#include <osmocom/crypt/auth.h>
 
 #include <openbsc/rest_octets.h>
 
@@ -47,9 +48,7 @@
 struct gsm_auth_tuple {
 	int use_count;
 	int key_seq;
-	uint8_t rand[16];
-	uint8_t sres[4];
-	uint8_t kc[8];
+	struct osmo_auth_vector vec;
 };
 #define GSM_KEY_SEQ_INVAL	7	/* GSM 04.08 - 10.5.1.2 */
 
diff --git a/openbsc/src/gprs/gprs_gmm.c b/openbsc/src/gprs/gprs_gmm.c
index 5f0a5fd..6b6e741 100644
--- a/openbsc/src/gprs/gprs_gmm.c
+++ b/openbsc/src/gprs/gprs_gmm.c
@@ -512,9 +512,9 @@
 
 	at = &ctx->auth_triplet;
 
-	if (TLVP_LEN(&tp, GSM48_IE_GMM_AUTH_SRES) != sizeof(at->sres) ||
-	    memcmp(TLVP_VAL(&tp, GSM48_IE_GMM_AUTH_SRES), at->sres,
-		   sizeof(at->sres)) != 0) {
+	if (TLVP_LEN(&tp, GSM48_IE_GMM_AUTH_SRES) != sizeof(at->vec.sres) ||
+	    memcmp(TLVP_VAL(&tp, GSM48_IE_GMM_AUTH_SRES), at->vec.sres,
+		   sizeof(at->vec.sres)) != 0) {
 
 		LOGMMCTXP(LOGL_NOTICE, ctx, "Received SRES doesn't match\n");
 		rc = gsm48_tx_gmm_auth_ciph_rej(ctx);
@@ -637,7 +637,8 @@
 		struct gsm_auth_tuple *at = &ctx->auth_triplet;
 
 		mmctx_timer_start(ctx, 3360, sgsn->cfg.timers.T3360);
-		return gsm48_tx_gmm_auth_ciph_req(ctx, at->rand, at->key_seq,
+		return gsm48_tx_gmm_auth_ciph_req(ctx, at->vec.rand,
+						  at->key_seq,
 						  GPRS_ALGO_GEA0);
 	}
 
@@ -1468,7 +1469,8 @@
 		}
 		at = &mm->auth_triplet;
 
-		gsm48_tx_gmm_auth_ciph_req(mm, at->rand, at->key_seq, GPRS_ALGO_GEA0);
+		gsm48_tx_gmm_auth_ciph_req(mm, at->vec.rand, at->key_seq,
+					   GPRS_ALGO_GEA0);
 		osmo_timer_schedule(&mm->timer, sgsn->cfg.timers.T3360, 0);
 		break;
 	case 3370:	/* waiting for IDENTITY RESPONSE */
diff --git a/openbsc/src/gprs/gprs_gsup_messages.c b/openbsc/src/gprs/gprs_gsup_messages.c
index 07485f7..0b1dc9b 100644
--- a/openbsc/src/gprs/gprs_gsup_messages.c
+++ b/openbsc/src/gprs/gprs_gsup_messages.c
@@ -3,6 +3,7 @@
 /*
  * (C) 2014 by Sysmocom s.f.m.c. GmbH
  * (C) 2015 by Holger Hans Peter Freyther
+ * (C) 2016 by Harald Welte <laforge@gnumonks.org>
  * All Rights Reserved
  *
  * Author: Jacob Erlbeck
@@ -82,7 +83,7 @@
 }
 
 static int decode_auth_info(uint8_t *data, size_t data_len,
-			   struct gsm_auth_tuple *auth_tuple)
+			   struct osmo_auth_vector *auth_vector)
 {
 	int rc;
 	uint8_t tag;
@@ -100,24 +101,24 @@
 
 		switch (iei) {
 		case GPRS_GSUP_RAND_IE:
-			if (value_len != sizeof(auth_tuple->rand))
+			if (value_len != sizeof(auth_vector->rand))
 				goto parse_error;
 
-			memcpy(auth_tuple->rand, value, value_len);
+			memcpy(auth_vector->rand, value, value_len);
 			break;
 
 		case GPRS_GSUP_SRES_IE:
-			if (value_len != sizeof(auth_tuple->sres))
+			if (value_len != sizeof(auth_vector->sres))
 				goto parse_error;
 
-			memcpy(auth_tuple->sres, value, value_len);
+			memcpy(auth_vector->sres, value, value_len);
 			break;
 
 		case GPRS_GSUP_KC_IE:
-			if (value_len != sizeof(auth_tuple->kc))
+			if (value_len != sizeof(auth_vector->kc))
 				goto parse_error;
 
-			memcpy(auth_tuple->kc, value, value_len);
+			memcpy(auth_vector->kc, value, value_len);
 			break;
 
 		default:
@@ -149,7 +150,7 @@
 	uint8_t *value;
 	size_t value_len;
 	static const struct gprs_gsup_pdp_info empty_pdp_info = {0};
-	static const struct gsm_auth_tuple empty_auth_info = {0};
+	static const struct osmo_auth_vector empty_auth_info = {0};
 	static const struct gprs_gsup_message empty_gsup_message = {0};
 
 	*gsup_msg = empty_gsup_message;
@@ -183,7 +184,7 @@
 	while (data_len > 0) {
 		enum gprs_gsup_iei iei;
 		struct gprs_gsup_pdp_info pdp_info;
-		struct gsm_auth_tuple auth_info;
+		struct osmo_auth_vector auth_info;
 
 		rc = gprs_shift_tlv(&data, &data_len, &tag, &value, &value_len);
 		if (rc < 0)
@@ -252,7 +253,7 @@
 			break;
 
 		case GPRS_GSUP_AUTH_TUPLE_IE:
-			if (gsup_msg->num_auth_tuples >= GPRS_GSUP_MAX_NUM_AUTH_INFO) {
+			if (gsup_msg->num_auth_vectors >= GPRS_GSUP_MAX_NUM_AUTH_INFO) {
 				LOGP(DGPRS, LOGL_ERROR,
 				     "GSUP IE type %d (AUTH_INFO) max exceeded\n",
 				     iei);
@@ -260,13 +261,12 @@
 			}
 
 			auth_info = empty_auth_info;
-			auth_info.key_seq = gsup_msg->num_auth_tuples;
 
 			rc = decode_auth_info(value, value_len, &auth_info);
 			if (rc < 0)
 				return rc;
 
-			gsup_msg->auth_tuples[gsup_msg->num_auth_tuples++] =
+			gsup_msg->auth_vectors[gsup_msg->num_auth_vectors++] =
 				auth_info;
 			break;
 
@@ -325,7 +325,7 @@
 }
 
 static void encode_auth_info(struct msgb *msg, enum gprs_gsup_iei iei,
-			     const struct gsm_auth_tuple *auth_tuple)
+			     const struct osmo_auth_vector *auth_vector)
 {
 	uint8_t *len_field;
 	size_t old_len;
@@ -334,13 +334,13 @@
 	old_len = msgb_length(msg);
 
 	msgb_tlv_put(msg, GPRS_GSUP_RAND_IE,
-		     sizeof(auth_tuple->rand), auth_tuple->rand);
+		     sizeof(auth_vector->rand), auth_vector->rand);
 
 	msgb_tlv_put(msg, GPRS_GSUP_SRES_IE,
-		     sizeof(auth_tuple->sres), auth_tuple->sres);
+		     sizeof(auth_vector->sres), auth_vector->sres);
 
 	msgb_tlv_put(msg, GPRS_GSUP_KC_IE,
-		     sizeof(auth_tuple->kc), auth_tuple->kc);
+		     sizeof(auth_vector->kc), auth_vector->kc);
 
 	/* Update length field */
 	*len_field = msgb_length(msg) - old_len;
@@ -406,14 +406,11 @@
 		}
 	}
 
-	for (idx = 0; idx < gsup_msg->num_auth_tuples; idx++) {
-		const struct gsm_auth_tuple *auth_info;
+	for (idx = 0; idx < gsup_msg->num_auth_vectors; idx++) {
+		const struct osmo_auth_vector *auth_vector;
 
-		auth_info = &gsup_msg->auth_tuples[idx];
+		auth_vector = &gsup_msg->auth_vectors[idx];
 
-		if (auth_info->key_seq == GSM_KEY_SEQ_INVAL)
-			continue;
-
-		encode_auth_info(msg, GPRS_GSUP_AUTH_TUPLE_IE, auth_info);
+		encode_auth_info(msg, GPRS_GSUP_AUTH_TUPLE_IE, auth_vector);
 	}
 }
diff --git a/openbsc/src/gprs/gprs_subscriber.c b/openbsc/src/gprs/gprs_subscriber.c
index 3467293..678c1de 100644
--- a/openbsc/src/gprs/gprs_subscriber.c
+++ b/openbsc/src/gprs/gprs_subscriber.c
@@ -199,18 +199,18 @@
 	struct sgsn_subscriber_data *sdata = subscr->sgsn_data;
 
 	LOGGSUBSCRP(LOGL_INFO, subscr,
-		"Got SendAuthenticationInfoResult, num_auth_tuples = %zu\n",
-		gsup_msg->num_auth_tuples);
+		"Got SendAuthenticationInfoResult, num_auth_vectors = %zu\n",
+		gsup_msg->num_auth_vectors);
 
-	if (gsup_msg->num_auth_tuples > 0) {
+	if (gsup_msg->num_auth_vectors > 0) {
 		memset(sdata->auth_triplets, 0, sizeof(sdata->auth_triplets));
 
 		for (idx = 0; idx < ARRAY_SIZE(sdata->auth_triplets); idx++)
 			sdata->auth_triplets[idx].key_seq = GSM_KEY_SEQ_INVAL;
 	}
 
-	for (idx = 0; idx < gsup_msg->num_auth_tuples; idx++) {
-		size_t key_seq = gsup_msg->auth_tuples[idx].key_seq;
+	for (idx = 0; idx < gsup_msg->num_auth_vectors; idx++) {
+		size_t key_seq = idx;
 		LOGGSUBSCRP(LOGL_DEBUG, subscr,
 			"Adding auth tuple, cksn = %zu\n", key_seq);
 		if (key_seq >= ARRAY_SIZE(sdata->auth_triplets)) {
@@ -219,7 +219,8 @@
 				key_seq);
 			continue;
 		}
-		sdata->auth_triplets[key_seq] = gsup_msg->auth_tuples[idx];
+		sdata->auth_triplets[key_seq].vec = gsup_msg->auth_vectors[idx];
+		sdata->auth_triplets[key_seq].key_seq = key_seq;
 	}
 
 	sdata->auth_triplets_updated = 1;
diff --git a/openbsc/src/gprs/sgsn_vty.c b/openbsc/src/gprs/sgsn_vty.c
index 3f61163..50f0e8f 100644
--- a/openbsc/src/gprs/sgsn_vty.c
+++ b/openbsc/src/gprs/sgsn_vty.c
@@ -613,11 +613,11 @@
 		vty_out(vty, "     seq # : %d, ",
 			at->key_seq);
 		vty_out(vty, "     RAND  : %s, ",
-			osmo_hexdump(at->rand, sizeof(at->rand)));
+			osmo_hexdump(at->vec.rand, sizeof(at->vec.rand)));
 		vty_out(vty, "     SRES  : %s, ",
-			osmo_hexdump(at->sres, sizeof(at->sres)));
+			osmo_hexdump(at->vec.sres, sizeof(at->vec.sres)));
 		vty_out(vty, "     Kc    : %s%s",
-			osmo_hexdump(at->kc, sizeof(at->kc)),
+			osmo_hexdump(at->vec.kc, sizeof(at->vec.kc)),
 			VTY_NEWLINE);
 	}
 
@@ -704,17 +704,17 @@
 
 	OSMO_ASSERT(subscr->sgsn_data);
 
-	if (osmo_hexparse(sres_str, &at.sres[0], sizeof(at.sres)) < 0) {
+	if (osmo_hexparse(sres_str, &at.vec.sres[0], sizeof(at.vec.sres)) < 0) {
 		vty_out(vty, "%% invalid SRES value '%s'%s",
 			sres_str, VTY_NEWLINE);
 		goto failed;
 	}
-	if (osmo_hexparse(rand_str, &at.rand[0], sizeof(at.rand)) < 0) {
+	if (osmo_hexparse(rand_str, &at.vec.rand[0], sizeof(at.vec.rand)) < 0) {
 		vty_out(vty, "%% invalid RAND value '%s'%s",
 			rand_str, VTY_NEWLINE);
 		goto failed;
 	}
-	if (osmo_hexparse(kc_str, &at.kc[0], sizeof(at.kc)) < 0) {
+	if (osmo_hexparse(kc_str, &at.vec.kc[0], sizeof(at.vec.kc)) < 0) {
 		vty_out(vty, "%% invalid Kc value '%s'%s",
 			kc_str, VTY_NEWLINE);
 		goto failed;
diff --git a/openbsc/src/libmsc/auth.c b/openbsc/src/libmsc/auth.c
index f30d56d..9191ae8 100644
--- a/openbsc/src/libmsc/auth.c
+++ b/openbsc/src/libmsc/auth.c
@@ -54,9 +54,9 @@
 	}
 
 	for (i=0; i<4; i++)
-		atuple->sres[i] = atuple->rand[i] ^ ainfo->a3a8_ki[i];
+		atuple->vec.sres[i] = atuple->vec.rand[i] ^ ainfo->a3a8_ki[i];
 	for (i=4; i<12; i++)
-		atuple->kc[i-4] = atuple->rand[i] ^ ainfo->a3a8_ki[i];
+		atuple->vec.kc[i-4] = atuple->vec.rand[i] ^ ainfo->a3a8_ki[i];
 
 	return 0;
 }
@@ -71,7 +71,7 @@
 		return -1;
 	}
 
-	comp128(ainfo->a3a8_ki, atuple->rand, atuple->sres, atuple->kc);
+	comp128(ainfo->a3a8_ki, atuple->vec.rand, atuple->vec.sres, atuple->vec.kc);
 
 	return 0;
 }
@@ -122,7 +122,7 @@
 	}
 	atuple->use_count = 1;
 
-	if (RAND_bytes(atuple->rand, sizeof(atuple->rand)) != 1) {
+	if (RAND_bytes(atuple->vec.rand, sizeof(atuple->vec.rand)) != 1) {
 		LOGP(DMM, LOGL_NOTICE, "RAND_bytes failed, can't generate new auth tuple\n");
 		return AUTH_ERROR;
 	}
diff --git a/openbsc/src/libmsc/db.c b/openbsc/src/libmsc/db.c
index 267b5ef..a23ec89 100644
--- a/openbsc/src/libmsc/db.c
+++ b/openbsc/src/libmsc/db.c
@@ -700,25 +700,25 @@
 	atuple->key_seq = dbi_result_get_ulonglong(result, "key_seq");
 
 	len = dbi_result_get_field_length(result, "rand");
-	if (len != sizeof(atuple->rand))
+	if (len != sizeof(atuple->vec.rand))
 		goto err_size;
 
 	blob = dbi_result_get_binary(result, "rand");
-	memcpy(atuple->rand, blob, len);
+	memcpy(atuple->vec.rand, blob, len);
 
 	len = dbi_result_get_field_length(result, "sres");
-	if (len != sizeof(atuple->sres))
+	if (len != sizeof(atuple->vec.sres))
 		goto err_size;
 
 	blob = dbi_result_get_binary(result, "sres");
-	memcpy(atuple->sres, blob, len);
+	memcpy(atuple->vec.sres, blob, len);
 
 	len = dbi_result_get_field_length(result, "kc");
-	if (len != sizeof(atuple->kc))
+	if (len != sizeof(atuple->vec.kc))
 		goto err_size;
 
 	blob = dbi_result_get_binary(result, "kc");
-	memcpy(atuple->kc, blob, len);
+	memcpy(atuple->vec.kc, blob, len);
 
 	dbi_result_free(result);
 
@@ -759,11 +759,11 @@
 
 	/* Update / Insert */
 	dbi_conn_quote_binary_copy(conn,
-		atuple->rand, sizeof(atuple->rand), &rand_str);
+		atuple->vec.rand, sizeof(atuple->vec.rand), &rand_str);
 	dbi_conn_quote_binary_copy(conn,
-		atuple->sres, sizeof(atuple->sres), &sres_str);
+		atuple->vec.sres, sizeof(atuple->vec.sres), &sres_str);
 	dbi_conn_quote_binary_copy(conn,
-		atuple->kc, sizeof(atuple->kc), &kc_str);
+		atuple->vec.kc, sizeof(atuple->vec.kc), &kc_str);
 
 	if (!upd) {
 		result = dbi_conn_queryf(conn,
diff --git a/openbsc/src/libmsc/gsm_04_08.c b/openbsc/src/libmsc/gsm_04_08.c
index 05cb886..f02f784 100644
--- a/openbsc/src/libmsc/gsm_04_08.c
+++ b/openbsc/src/libmsc/gsm_04_08.c
@@ -234,11 +234,11 @@
 	/* Then do whatever is needed ... */
 	if (rc == AUTH_DO_AUTH_THEN_CIPH) {
 		/* Start authentication */
-		return gsm48_tx_mm_auth_req(conn, op->atuple.rand, op->atuple.key_seq);
+		return gsm48_tx_mm_auth_req(conn, op->atuple.vec.rand, op->atuple.key_seq);
 	} else if (rc == AUTH_DO_CIPH) {
 		/* Start ciphering directly */
 		return gsm0808_cipher_mode(conn, net->a5_encryption,
-		                           op->atuple.kc, 8, 0);
+		                           op->atuple.vec.kc, 8, 0);
 	}
 
 	return -EINVAL; /* not reached */
@@ -1102,12 +1102,12 @@
 	}
 
 	/* Validate SRES */
-	if (memcmp(conn->sec_operation->atuple.sres, ar->sres,4)) {
+	if (memcmp(conn->sec_operation->atuple.vec.sres, ar->sres,4)) {
 		int rc;
 		gsm_cbfn *cb = conn->sec_operation->cb;
 
 		DEBUGPC(DMM, "Invalid (expected %s)\n",
-			osmo_hexdump(conn->sec_operation->atuple.sres, 4));
+			osmo_hexdump(conn->sec_operation->atuple.vec.sres, 4));
 
 		if (cb)
 			cb(GSM_HOOK_RR_SECURITY, GSM_SECURITY_AUTH_FAILED,
@@ -1122,7 +1122,7 @@
 
 	/* Start ciphering */
 	return gsm0808_cipher_mode(conn, net->a5_encryption,
-	                           conn->sec_operation->atuple.kc, 8, 0);
+	                           conn->sec_operation->atuple.vec.kc, 8, 0);
 }
 
 /* Receive a GSM 04.08 Mobility Management (MM) message */
diff --git a/openbsc/src/libmsc/vty_interface_layer3.c b/openbsc/src/libmsc/vty_interface_layer3.c
index 790fedf..4c2088a 100644
--- a/openbsc/src/libmsc/vty_interface_layer3.c
+++ b/openbsc/src/libmsc/vty_interface_layer3.c
@@ -94,13 +94,13 @@
 		vty_out(vty, "     seq # : %d%s",
 			atuple.key_seq, VTY_NEWLINE);
 		vty_out(vty, "     RAND  : %s%s",
-			osmo_hexdump(atuple.rand, sizeof(atuple.rand)),
+			osmo_hexdump(atuple.vec.rand, sizeof(atuple.vec.rand)),
 			VTY_NEWLINE);
 		vty_out(vty, "     SRES  : %s%s",
-			osmo_hexdump(atuple.sres, sizeof(atuple.sres)),
+			osmo_hexdump(atuple.vec.sres, sizeof(atuple.vec.sres)),
 			VTY_NEWLINE);
 		vty_out(vty, "     Kc    : %s%s",
-			osmo_hexdump(atuple.kc, sizeof(atuple.kc)),
+			osmo_hexdump(atuple.vec.kc, sizeof(atuple.vec.kc)),
 			VTY_NEWLINE);
 	}
 
diff --git a/openbsc/tests/mm_auth/mm_auth_test.c b/openbsc/tests/mm_auth/mm_auth_test.c
index 34d96f1..b8777a8 100644
--- a/openbsc/tests/mm_auth/mm_auth_test.c
+++ b/openbsc/tests/mm_auth/mm_auth_test.c
@@ -26,9 +26,9 @@
 	print2buf("gsm_auth_tuple {\n");
 	print2buf("  .use_count = %d\n", atuple->use_count);
 	print2buf("  .key_seq = %d\n", atuple->key_seq);
-	print2buf("  .rand = %s\n", osmo_hexdump(atuple->rand, sizeof(atuple->rand)));
-	print2buf("  .sres = %s\n", osmo_hexdump(atuple->sres, sizeof(atuple->sres)));
-	print2buf("  .kc = %s\n", osmo_hexdump(atuple->kc, sizeof(atuple->kc)));
+	print2buf("  .rand = %s\n", osmo_hexdump(atuple->vec.rand, sizeof(atuple->vec.rand)));
+	print2buf("  .sres = %s\n", osmo_hexdump(atuple->vec.sres, sizeof(atuple->vec.sres)));
+	print2buf("  .kc = %s\n", osmo_hexdump(atuple->vec.kc, sizeof(atuple->vec.kc)));
 	print2buf("}\n");
 #undef print2buf
 
diff --git a/openbsc/tests/sgsn/sgsn_test.c b/openbsc/tests/sgsn/sgsn_test.c
index 1acd6f2..fe41e75 100644
--- a/openbsc/tests/sgsn/sgsn_test.c
+++ b/openbsc/tests/sgsn/sgsn_test.c
@@ -1132,7 +1132,7 @@
 int my_subscr_request_auth_info_real_auth(struct sgsn_mm_ctx *mmctx)
 {
 	struct gsm_auth_tuple at = {
-		.sres = {0x51, 0xe5, 0x51, 0xe5},
+		.vec.sres = {0x51, 0xe5, 0x51, 0xe5},
 		.key_seq = 0
 	};