confd: add the ability to set speed, duplex and autoneg

Add the ability to configure interface speed, duplex and autoneg.
Initially this was pared with YANG model deviations that restricted
explicit interface speed and duplex when autoneg was enabled. But due
to conflicting default states in YANG, this code was dropped.

Signed-off-by: Richard Alpe <richard@bit42.se>

src/confd/src/ietf-interfaces.c

@@ -653,6 +653,193 @@ skip_mtu:
 	return err;
 }
 
+static int netdag_write_ethtool(struct dagger *net, const char *ifname,
+				const char *fmt, ...)
+{
+	va_list ap;
+	FILE *fp;
+
+	fp = dagger_fopen_next(net, "init", ifname, 65, "ethtool.sh");
+	if (!fp)
+		return -EIO;
+
+	va_start(ap, fmt);
+	vfprintf(fp, fmt, ap);
+	va_end(ap);
+
+	fclose(fp);
+
+	return 0;
+}
+
+static const char *lyd_get_autoneg(struct lyd_node *cif)
+{
+	struct lydx_diff nd;
+	struct lyd_node *node;
+
+	node = lydx_get_descendant(lyd_child(cif), "ethernet", "auto-negotiation", "enable", NULL);
+	if (node && lydx_get_diff(node, &nd) && nd.new)
+		return (strcmp(nd.val, "true") == 0) ? "on" : "off";
+
+	return NULL;
+}
+
+static const char *lyd_get_duplex(struct lyd_node *cif)
+{
+	struct lydx_diff nd;
+	struct lyd_node *node;
+
+	node = lydx_get_descendant(lyd_child(cif), "ethernet", "duplex", NULL);
+	if (node && lydx_get_diff(node, &nd) && nd.new)
+		return nd.val;
+
+	return NULL;
+}
+
+static int lyd_get_speed(struct lyd_node *cif)
+{
+	struct lydx_diff nd;
+	struct lyd_node *n;
+
+	n = lydx_get_descendant(lyd_child(cif), "ethernet", "speed", NULL);
+	if (n && lydx_get_diff(n, &nd) && nd.new)
+		return (int)(atof(nd.val) * 1000);
+
+	return 0;
+}
+
+static int lyd_speed_has_changed(struct lyd_node *dif)
+{
+	struct lydx_diff nd;
+	struct lyd_node *n;
+
+	n = lydx_get_descendant(lyd_child(dif), "ethernet", "speed", NULL);
+	return (n && lydx_get_diff(n, &nd));
+}
+
+static int lyd_duplex_has_changed(struct lyd_node *dif)
+{
+	struct lydx_diff nd;
+	struct lyd_node *n;
+
+	n = lydx_get_descendant(lyd_child(dif), "ethernet", "duplex", NULL);
+	return (n && lydx_get_diff(n, &nd));
+}
+
+static int lyd_autoneg_has_changed(struct lyd_node *dif)
+{
+	struct lydx_diff nd;
+	struct lyd_node *n;
+
+	n = lydx_get_descendant(lyd_child(dif), "ethernet", "auto-negotiation", "enable", NULL);
+	return (n && lydx_get_diff(n, &nd));
+}
+
+static int lyd_autoneg_is_on(struct lyd_node *cif)
+{
+	const char *val;
+
+	val = lyd_get_autoneg(cif);
+	if (!val) {
+		/* TODO Change this to error when auto-neg is true in factory config */
+		return 1;
+	}
+	return (strcmp(val, "on") == 0);
+}
+
+static int netdag_set_autoneg_off(struct dagger *net, const char *ifname,
+				  const char *duplex, int speed)
+{
+	if (!speed || !duplex) {
+		sr_session_set_error_message(net->session,
+					     "Autoneg off requires explicit speed and duplex");
+		return SR_ERR_INVAL_ARG;
+	}
+
+	return netdag_write_ethtool(net, ifname,
+				    "ethtool -s %s autoneg off duplex %s speed %d\n",
+				    ifname, duplex, speed);
+}
+
+static int netdag_set_autoneg_on(struct dagger *net, const char *ifname)
+{
+	return netdag_write_ethtool(net, ifname, "ethtool -s %s autoneg on\n", ifname);
+}
+
+static int netdag_set_autoneg(struct dagger *net, const char *ifname, struct lyd_node *cif)
+{
+	const char *autoneg = lyd_get_autoneg(cif);
+	const char *duplex = lyd_get_duplex(cif);
+	int speed = lyd_get_speed(cif);
+
+	if (!autoneg)
+		return SR_ERR_INVAL_ARG;
+
+	if (strcmp(autoneg, "off") == 0)
+		return netdag_set_autoneg_off(net, ifname, duplex, speed);
+
+	return netdag_set_autoneg_on(net, ifname);
+}
+
+static int netdag_set_speed(struct dagger *net, const char *ifname, struct lyd_node *cif)
+{
+	int speed = lyd_get_speed(cif);
+
+	if (!speed && !lyd_autoneg_is_on(cif)) {
+		sr_session_set_error_message(net->session,
+					     "Can't remove speed when autoneg is disabled");
+		return SR_ERR_INVAL_ARG;
+	}
+
+	return netdag_write_ethtool(net, ifname, "ethtool -s %s speed %d\n",
+				    ifname, speed);
+}
+
+static int netdag_set_duplex(struct dagger *net, const char *ifname, struct lyd_node *cif)
+{
+	const char *duplex = lyd_get_duplex(cif);
+
+	/**
+	 * Duplex has a default value, no need to check if autoneg is off and
+	 * the duplex is removed, which would be a problem otherwise.
+	 */
+
+	return netdag_write_ethtool(net, ifname, "ethtool -s %s duplex %s\n",
+				    ifname, duplex);
+}
+
+static int netdag_gen_ethtool(struct dagger *net, struct lyd_node *cif, struct lyd_node *dif)
+{
+	const char *ifname = lydx_get_cattr(cif, "name");
+	int err;
+
+	if (!strcmp(ifname, "lo"))
+		return SR_ERR_OK;
+
+	/**
+	 * Autoneg on means duplex and speed doesn't matter.
+	 * Autoneg off requires and set both speed and duplex.
+	 *
+	 * Either way, if autoneg has changed duplex and speed are handled.
+	 */
+	if (lyd_autoneg_has_changed(dif))
+		return netdag_set_autoneg(net, ifname, cif);
+
+	if (lyd_duplex_has_changed(dif)) {
+		err = netdag_set_duplex(net, ifname, cif);
+		if (err)
+			return err;
+	}
+
+	if (lyd_speed_has_changed(dif)) {
+		err = netdag_set_speed(net, ifname, cif);
+		if (err)
+			return err;
+	}
+
+	return SR_ERR_OK;
+}
+
 static int bridge_diff_vlan_port(struct dagger *net, FILE *br, const char *brname, int vid,
 				       const char *brport, int tagged, enum lydx_op op)
 {
@@ -1140,6 +1327,8 @@ static sr_error_t netdag_gen_iface(struct dagger *net,
 
 	err = err ? : netdag_gen_sysctl(net, cif, dif);
 
+	err = err ? : netdag_gen_ethtool(net, cif, dif);
+
 err_close_ip:
 	fclose(ip);
 err: