diff --git a/TODO-RELEASE b/TODO-RELEASE
index 7785711e..0c3e87ee 100644
--- a/TODO-RELEASE
+++ b/TODO-RELEASE
@@ -17,3 +17,4 @@ libosmo-sigtran	ABI change	struct osmo_xua_server: new field(s) at the end
 libosmo-sigtran	API added	osmo_ss7_asp_get_trans_proto()
 libosmo-sigtran	API added	osmo_ss7_asp_{find2,find_or_create2}()
 libosmo-sigtran	API added	osmo_ss7_xua_server_{find2,create2}()
+libosmo-netif >1.4.0	osmo_io SCTP support
diff --git a/src/osmo_ss7_asp.c b/src/osmo_ss7_asp.c
index 5bab5ffc..e023880f 100644
--- a/src/osmo_ss7_asp.c
+++ b/src/osmo_ss7_asp.c
@@ -601,9 +601,9 @@ void osmo_ss7_asp_destroy(struct osmo_ss7_asp *asp)
 	talloc_free(asp);
 }
 
-static int xua_cli_read_cb(struct osmo_stream_cli *conn);
-static int ipa_cli_read_cb(struct osmo_stream_cli *conn);
-static int m3ua_tcp_cli_read_cb(struct osmo_stream_cli *conn);
+static int xua_cli_read_cb(struct osmo_stream_cli *conn, struct msgb *msg);
+static int ipa_cli_read_cb(struct osmo_stream_cli *conn, struct msgb *msg);
+static int m3ua_tcp_cli_read_cb(struct osmo_stream_cli *conn, struct msgb *msg);
 static int xua_cli_connect_cb(struct osmo_stream_cli *cli);
 
 int osmo_ss7_asp_restart(struct osmo_ss7_asp *asp)
@@ -645,19 +645,22 @@ int osmo_ss7_asp_restart(struct osmo_ss7_asp *asp)
 		switch (asp->cfg.proto) {
 		case OSMO_SS7_ASP_PROT_IPA:
 			OSMO_ASSERT(asp->cfg.trans_proto == IPPROTO_TCP);
-			osmo_stream_cli_set_read_cb(asp->client, ipa_cli_read_cb);
+			osmo_stream_cli_set_read_cb2(asp->client, ipa_cli_read_cb);
+			osmo_stream_cli_set_segmentation_cb(asp->client, osmo_ipa_segmentation_cb);
 			break;
 		case OSMO_SS7_ASP_PROT_M3UA:
-			if (asp->cfg.trans_proto == IPPROTO_SCTP)
-				osmo_stream_cli_set_read_cb(asp->client, xua_cli_read_cb);
-			else if (asp->cfg.trans_proto == IPPROTO_TCP)
-				osmo_stream_cli_set_read_cb(asp->client, m3ua_tcp_cli_read_cb);
-			else
+			if (asp->cfg.trans_proto == IPPROTO_SCTP) {
+				osmo_stream_cli_set_read_cb2(asp->client, xua_cli_read_cb);
+				osmo_stream_cli_set_segmentation_cb(asp->client, NULL);
+			} else if (asp->cfg.trans_proto == IPPROTO_TCP) {
+				osmo_stream_cli_set_read_cb2(asp->client, m3ua_tcp_cli_read_cb);
+				osmo_stream_cli_set_segmentation_cb(asp->client, xua_segmentation_cb);
+			} else
 				OSMO_ASSERT(0);
 			break;
 		default:
 			OSMO_ASSERT(asp->cfg.trans_proto == IPPROTO_SCTP);
-			osmo_stream_cli_set_read_cb(asp->client, xua_cli_read_cb);
+			osmo_stream_cli_set_read_cb2(asp->client, xua_cli_read_cb);
 			break;
 		}
 		osmo_stream_cli_set_data(asp->client, asp);
@@ -789,33 +792,11 @@ static void log_sctp_notification(struct osmo_ss7_asp *asp, const char *pfx,
 }
 
 /* netif code tells us we can read something from the socket */
-int ss7_asp_ipa_srv_conn_cb(struct osmo_stream_srv *conn)
+int ss7_asp_ipa_srv_conn_cb(struct osmo_stream_srv *conn, struct msgb *msg)
 {
 	int fd = osmo_stream_srv_get_fd(conn);
 	struct osmo_ss7_asp *asp = osmo_stream_srv_get_data(conn);
-	struct msgb *msg = NULL;
-	int rc;
 
-	OSMO_ASSERT(fd >= 0);
-
-	/* read IPA message from socket and process it */
-	rc = ipa_msg_recv_buffered(fd, &msg, &asp->pending_msg);
-	LOGPASP(asp, DLSS7, LOGL_DEBUG, "%s(): ipa_msg_recv_buffered() returned %d\n",
-		__func__, rc);
-	if (rc <= 0) {
-		if (rc == -EAGAIN) {
-			/* more data needed */
-			return 0;
-		}
-		osmo_stream_srv_destroy(conn);
-		return rc;
-	}
-	if (osmo_ipa_process_msg(msg) < 0) {
-		LOGPASP(asp, DLSS7, LOGL_ERROR, "Bad IPA message\n");
-		osmo_stream_srv_destroy(conn);
-		msgb_free(msg);
-		return -1;
-	}
 	msg->dst = asp;
 	rate_ctr_inc2(asp->ctrg, SS7_ASP_CTR_PKT_RX_TOTAL);
 	/* we can use the 'fd' return value of osmo_stream_srv_get_fd() here unverified as all we do
@@ -824,19 +805,14 @@ int ss7_asp_ipa_srv_conn_cb(struct osmo_stream_srv *conn)
 }
 
 /* netif code tells us we can read something from the socket */
-int ss7_asp_xua_srv_conn_cb(struct osmo_stream_srv *conn)
+int ss7_asp_xua_srv_conn_cb(struct osmo_stream_srv *conn, struct msgb *msg)
 {
 	struct osmo_ss7_asp *asp = osmo_stream_srv_get_data(conn);
-	struct msgb *msg = m3ua_msgb_alloc("xUA Server Rx");
 	unsigned int ppid;
 	int flags;
-	int rc;
+	int rc = 0;
 
-	if (!msg)
-		return -ENOMEM;
-
-	/* read xUA message from socket and process it */
-	rc = osmo_stream_srv_recv(conn, msg);
+	/* process the received xUA message */
 	flags = msgb_sctp_msg_flags(msg);
 
 	LOGPASP(asp, DLSS7, LOGL_DEBUG, "%s(): sctp_recvmsg() returned %d (flags=0x%x)\n",
@@ -855,22 +831,6 @@ int ss7_asp_xua_srv_conn_cb(struct osmo_stream_srv *conn)
 		default:
 			break;
 		}
-
-		if (rc == 0) {
-			osmo_stream_srv_destroy(conn);
-			rc = -EBADF;
-		} else {
-			rc = 0;
-		}
-		goto out;
-	}
-	if (rc < 0) {
-		osmo_stream_srv_destroy(conn);
-		rc = -EBADF;
-		goto out;
-	} else if (rc == 0) {
-		osmo_stream_srv_destroy(conn);
-		rc = -EBADF;
 		goto out;
 	}
 
@@ -890,73 +850,38 @@ out:
 	return rc;
 }
 
-/* netif code tells us we can read something from the socket */
-int ss7_asp_m3ua_tcp_srv_conn_cb(struct osmo_stream_srv *conn)
+int xua_segmentation_cb(struct msgb *msg)
 {
-	struct osmo_ss7_asp *asp = osmo_stream_srv_get_data(conn);
-	int fd = osmo_stream_srv_get_fd(conn);
-	struct msgb *msg = asp->pending_msg;
 	const struct xua_common_hdr *hdr;
 	size_t msg_length;
-	int rc;
 
-	OSMO_ASSERT(fd >= 0);
+	if (msgb_length(msg) < sizeof(*hdr))
+		return -EAGAIN;
 
-	if (msg == NULL) {
-		msg = m3ua_msgb_alloc(__func__);
-		asp->pending_msg = msg;
-	}
-
-	/* read message header first */
-	if (msg->len < sizeof(*hdr)) {
-		errno = 0;
-		rc = recv(fd, msg->tail, sizeof(*hdr) - msg->len, 0);
-		if (rc <= 0) {
-			if (errno == EAGAIN || errno == EINTR)
-				return 0; /* need more data */
-			osmo_stream_srv_destroy(conn);
-			asp->pending_msg = NULL;
-			msgb_free(msg);
-			return rc;
-		}
-
-		msgb_put(msg, rc);
-		if (msg->len < sizeof(*hdr))
-			return 0; /* need more data */
-	}
-
-	hdr = (const struct xua_common_hdr *)msg->data;
+	hdr = (const struct xua_common_hdr *) msg->data;
 	msg_length = ntohl(hdr->msg_length); /* includes sizeof(*hdr) */
 
-	/* read the rest of the message */
-	if (msg->len < msg_length) {
-		errno = 0;
-		rc = recv(fd, msg->tail, msg_length - msg->len, 0);
-		if (rc <= 0) {
-			if (errno == EAGAIN || errno == EINTR)
-				return 0; /* need more data */
-			osmo_stream_srv_destroy(conn);
-			asp->pending_msg = NULL;
-			msgb_free(msg);
-			return rc;
-		}
+	return msg_length;
+}
 
-		msgb_put(msg, rc);
-		if (msg->len < msg_length)
-			return 0; /* need more data */
-	}
+/* netif code tells us we can read something from the socket */
+int ss7_asp_m3ua_tcp_srv_conn_cb(struct osmo_stream_srv *conn, struct msgb *msg)
+{
+	struct osmo_ss7_asp *asp = osmo_stream_srv_get_data(conn);
+	const struct xua_common_hdr *hdr;
+	int rc;
 
 	msg->dst = asp;
 	rate_ctr_inc2(asp->ctrg, SS7_ASP_CTR_PKT_RX_TOTAL);
 
 	/* spoof SCTP Stream ID */
+	hdr = (const struct xua_common_hdr *)msg->data;
 	if (hdr->msg_class == M3UA_MSGC_XFER)
 		msgb_sctp_stream(msg) = 1;
 	else
 		msgb_sctp_stream(msg) = 0;
 
 	rc = m3ua_rx_msg(asp, msg);
-	asp->pending_msg = NULL;
 	msgb_free(msg);
 
 	return rc;
@@ -1016,33 +941,17 @@ static void xua_cli_close_and_reconnect(struct osmo_stream_cli *cli)
 }
 
 /* read call-back for IPA/SCCPlite socket */
-static int ipa_cli_read_cb(struct osmo_stream_cli *conn)
+static int ipa_cli_read_cb(struct osmo_stream_cli *conn, struct msgb *msg)
 {
 	int fd = osmo_stream_cli_get_fd(conn);
 	struct osmo_ss7_asp *asp = osmo_stream_cli_get_data(conn);
-	struct msgb *msg = NULL;
-	int rc;
 
-	OSMO_ASSERT(fd >= 0);
-
-	/* read IPA message from socket and process it */
-	rc = ipa_msg_recv_buffered(fd, &msg, &asp->pending_msg);
-	LOGPASP(asp, DLSS7, LOGL_DEBUG, "%s(): ipa_msg_recv_buffered() returned %d\n",
-		__func__, rc);
-	if (rc <= 0) {
-		if (rc == -EAGAIN) {
-			/* more data needed */
-			return 0;
-		}
-		xua_cli_close_and_reconnect(conn);
-		return rc;
-	}
-	if (osmo_ipa_process_msg(msg) < 0) {
-		LOGPASP(asp, DLSS7, LOGL_ERROR, "Bad IPA message\n");
-		xua_cli_close_and_reconnect(conn);
+	if (msgb_length(msg) == 0) {
+		xua_cli_close_and_reconnect(asp->client);
 		msgb_free(msg);
-		return -1;
+		return 0;
 	}
+
 	msg->dst = asp;
 	rate_ctr_inc2(asp->ctrg, SS7_ASP_CTR_PKT_RX_TOTAL);
 	/* we can use the 'fd' return value of osmo_stream_srv_get_fd() here unverified as all we do
@@ -1051,94 +960,34 @@ static int ipa_cli_read_cb(struct osmo_stream_cli *conn)
 }
 
 /* read call-back for M3UA-over-TCP socket */
-static int m3ua_tcp_cli_read_cb(struct osmo_stream_cli *conn)
+static int m3ua_tcp_cli_read_cb(struct osmo_stream_cli *conn, struct msgb *msg)
 {
-	struct osmo_ss7_asp *asp = osmo_stream_cli_get_data(conn);
-	int fd = osmo_stream_cli_get_fd(conn);
-	struct msgb *msg = asp->pending_msg;
 	const struct xua_common_hdr *hdr;
-	size_t msg_length;
-	int rc;
 
-	OSMO_ASSERT(fd >= 0);
-
-	if (msg == NULL) {
-		msg = m3ua_msgb_alloc(__func__);
-		asp->pending_msg = msg;
-	}
-
-	/* read message header first */
-	if (msg->len < sizeof(*hdr)) {
-		errno = 0;
-		rc = recv(fd, msg->tail, sizeof(*hdr) - msg->len, 0);
-		if (rc <= 0) {
-			if (errno == EAGAIN || errno == EINTR)
-				return 0; /* need more data */
-			xua_cli_close_and_reconnect(conn);
-			asp->pending_msg = NULL;
-			msgb_free(msg);
-			return rc;
-		}
-
-		msgb_put(msg, rc);
-		if (msg->len < sizeof(*hdr))
-			return 0; /* need more data */
-	}
-
-	hdr = (const struct xua_common_hdr *)msg->data;
-	msg_length = ntohl(hdr->msg_length); /* includes sizeof(*hdr) */
-
-	/* read the rest of the message */
-	if (msg->len < msg_length) {
-		errno = 0;
-		rc = recv(fd, msg->tail, msg_length - msg->len, 0);
-		if (rc <= 0) {
-			if (errno == EAGAIN || errno == EINTR)
-				return 0; /* need more data */
-			xua_cli_close_and_reconnect(conn);
-			asp->pending_msg = NULL;
-			msgb_free(msg);
-			return rc;
-		}
-
-		msgb_put(msg, rc);
-		if (msg->len < msg_length)
-			return 0; /* need more data */
-	}
-
-	msg->dst = asp;
-	rate_ctr_inc2(asp->ctrg, SS7_ASP_CTR_PKT_RX_TOTAL);
+	/* spoof SCTP PPID */
+	msgb_sctp_ppid(msg) = M3UA_PPID;
 
 	/* spoof SCTP Stream ID */
+	hdr = (const struct xua_common_hdr *) msg->data;
 	if (hdr->msg_class == M3UA_MSGC_XFER)
 		msgb_sctp_stream(msg) = 1;
 	else
 		msgb_sctp_stream(msg) = 0;
 
-	rc = m3ua_rx_msg(asp, msg);
-	asp->pending_msg = NULL;
-	msgb_free(msg);
-
-	return rc;
+	return xua_cli_read_cb(conn, msg);
 }
 
-static int xua_cli_read_cb(struct osmo_stream_cli *conn)
+static int xua_cli_read_cb(struct osmo_stream_cli *conn, struct msgb *msg)
 {
 	struct osmo_ss7_asp *asp = osmo_stream_cli_get_data(conn);
-	struct msgb *msg = m3ua_msgb_alloc("xUA Client Rx");
 	unsigned int ppid;
 	int flags;
 	int rc;
 
-	if (!msg)
-		return -ENOMEM;
-
-	/* read xUA message from socket and process it */
-	rc = osmo_stream_cli_recv(conn, msg);
 	flags = msgb_sctp_msg_flags(msg);
 
 	LOGPASP(asp, DLSS7, LOGL_DEBUG, "%s(): sctp_recvmsg() returned %d (flags=0x%x)\n",
-		__func__, rc, flags);
+		__func__, msgb_length(msg), flags);
 
 	if (flags & OSMO_STREAM_SCTP_MSG_FLAGS_NOTIFICATION) {
 		union sctp_notification *notif = (union sctp_notification *) msgb_data(msg);
@@ -1153,17 +1002,12 @@ static int xua_cli_read_cb(struct osmo_stream_cli *conn)
 		default:
 			break;
 		}
-
-		if (rc == 0)
-			xua_cli_close_and_reconnect(conn);
-		rc = 0;
 		goto out;
 	}
-	if (rc < 0) {
-		xua_cli_close_and_reconnect(conn);
-		goto out;
-	} else if (rc == 0) {
+
+	if (msgb_length(msg) == 0) {
 		xua_cli_close_and_reconnect(conn);
+		rc = 0;
 		goto out;
 	}
 
diff --git a/src/osmo_ss7_xua_srv.c b/src/osmo_ss7_xua_srv.c
index 6da7b7ac..ce104484 100644
--- a/src/osmo_ss7_xua_srv.c
+++ b/src/osmo_ss7_xua_srv.c
@@ -67,32 +67,11 @@ static int xua_accept_cb(struct osmo_stream_srv_link *link, int fd)
 	struct osmo_ss7_asp *asp;
 	char *sock_name = osmo_sock_get_name(link, fd);
 	const char *proto_name = get_value_string(osmo_ss7_asp_protocol_vals, oxs->cfg.proto);
-	int (*read_cb)(struct osmo_stream_srv *conn) = NULL;
 	int rc = 0;
 
 	LOGP(DLSS7, LOGL_INFO, "%s: New %s connection accepted\n", sock_name, proto_name);
 
-	switch (oxs->cfg.proto) {
-	case OSMO_SS7_ASP_PROT_IPA:
-		OSMO_ASSERT(oxs->cfg.trans_proto == IPPROTO_TCP);
-		read_cb = &ss7_asp_ipa_srv_conn_cb;
-		break;
-	case OSMO_SS7_ASP_PROT_M3UA:
-		if (oxs->cfg.trans_proto == IPPROTO_SCTP)
-			read_cb = &ss7_asp_xua_srv_conn_cb;
-		else if (oxs->cfg.trans_proto == IPPROTO_TCP)
-			read_cb = &ss7_asp_m3ua_tcp_srv_conn_cb;
-		else
-			OSMO_ASSERT(0);
-		break;
-	default:
-		OSMO_ASSERT(oxs->cfg.trans_proto == IPPROTO_SCTP);
-		read_cb = &ss7_asp_xua_srv_conn_cb;
-		break;
-	}
-
-	srv = osmo_stream_srv_create(oxs, link, fd, read_cb,
-				     &ss7_asp_xua_srv_conn_closed_cb, NULL);
+	srv = osmo_stream_srv_create2(oxs, link, fd, NULL);
 	if (!srv) {
 		LOGP(DLSS7, LOGL_ERROR, "%s: Unable to create stream server "
 		     "for connection\n", sock_name);
@@ -101,6 +80,28 @@ static int xua_accept_cb(struct osmo_stream_srv_link *link, int fd)
 		return -1;
 	}
 
+	switch (oxs->cfg.proto) {
+	case OSMO_SS7_ASP_PROT_IPA:
+		osmo_stream_srv_set_read_cb(srv, ss7_asp_ipa_srv_conn_cb);
+		osmo_stream_srv_set_segmentation_cb(srv, osmo_ipa_segmentation_cb);
+		break;
+	case OSMO_SS7_ASP_PROT_M3UA:
+		if (oxs->cfg.trans_proto == IPPROTO_SCTP)
+			osmo_stream_srv_set_read_cb(srv, &ss7_asp_xua_srv_conn_cb);
+		else if (oxs->cfg.trans_proto == IPPROTO_TCP) {
+			osmo_stream_srv_set_read_cb(srv, &ss7_asp_m3ua_tcp_srv_conn_cb);
+			osmo_stream_srv_set_segmentation_cb(srv, xua_segmentation_cb);
+		} else
+			OSMO_ASSERT(0);
+		break;
+	default:
+		OSMO_ASSERT(oxs->cfg.trans_proto == IPPROTO_SCTP);
+		osmo_stream_srv_set_read_cb(srv, &ss7_asp_xua_srv_conn_cb);
+		osmo_stream_srv_set_segmentation_cb(srv, NULL);
+		break;
+	}
+	osmo_stream_srv_set_closed_cb(srv, ss7_asp_xua_srv_conn_closed_cb);
+
 	asp = ss7_asp_find_by_socket_addr(fd, oxs->cfg.trans_proto);
 	if (asp) {
 		LOGP(DLSS7, LOGL_INFO, "%s: matched connection to ASP %s\n",
diff --git a/src/ss7_internal.h b/src/ss7_internal.h
index 758da90f..b737fa2a 100644
--- a/src/ss7_internal.h
+++ b/src/ss7_internal.h
@@ -24,9 +24,9 @@ struct osmo_ss7_asp *ss7_asp_find_by_socket_addr(int fd, int trans_proto);
 
 bool ss7_asp_protocol_check_trans_proto(enum osmo_ss7_asp_protocol proto, int trans_proto);
 int ss7_default_trans_proto_for_asp_proto(enum osmo_ss7_asp_protocol proto);
-int ss7_asp_ipa_srv_conn_cb(struct osmo_stream_srv *conn);
-int ss7_asp_xua_srv_conn_cb(struct osmo_stream_srv *conn);
-int ss7_asp_m3ua_tcp_srv_conn_cb(struct osmo_stream_srv *conn);
+int ss7_asp_ipa_srv_conn_cb(struct osmo_stream_srv *conn, struct msgb *msg);
+int ss7_asp_xua_srv_conn_cb(struct osmo_stream_srv *conn, struct msgb *msg);
+int ss7_asp_m3ua_tcp_srv_conn_cb(struct osmo_stream_srv *conn, struct msgb *msg);
 int ss7_asp_xua_srv_conn_closed_cb(struct osmo_stream_srv *srv);
 int ss7_asp_apply_peer_primary_address(const struct osmo_ss7_asp *asp);
 int ss7_asp_apply_primary_address(const struct osmo_ss7_asp *asp);
@@ -38,6 +38,8 @@ int ss7_asp_peer_find_host(const struct osmo_ss7_asp_peer *peer, const char *hos
 
 bool ss7_xua_server_set_default_local_hosts(struct osmo_xua_server *oxs);
 
+int xua_segmentation_cb(struct msgb *msg);
+
 enum ss7_as_ctr {
 	SS7_AS_CTR_RX_MSU_TOTAL,
 	SS7_AS_CTR_TX_MSU_TOTAL,