1// SPDX-License-Identifier: GPL-2.0 2/* Copyright 2011-2014 Autronica Fire and Security AS 3 * 4 * Author(s): 5 * 2011-2014 Arvid Brodin, arvid.brodin@alten.se 6 * 7 * Frame handler other utility functions for HSR and PRP. 8 */ 9 10#include "hsr_slave.h" 11#include <linux/etherdevice.h> 12#include <linux/if_arp.h> 13#include <linux/if_vlan.h> 14#include "hsr_main.h" 15#include "hsr_device.h" 16#include "hsr_forward.h" 17#include "hsr_framereg.h" 18 19bool hsr_invalid_dan_ingress_frame(__be16 protocol) 20{ 21 return (protocol != htons(ETH_P_PRP) && protocol != htons(ETH_P_HSR)); 22} 23 24static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb) 25{ 26 struct sk_buff *skb = *pskb; 27 struct hsr_port *port; 28 struct hsr_priv *hsr; 29 __be16 protocol; 30 31 /* Packets from dev_loopback_xmit() do not have L2 header, bail out */ 32 if (unlikely(skb->pkt_type == PACKET_LOOPBACK)) 33 return RX_HANDLER_PASS; 34 35 if (!skb_mac_header_was_set(skb)) { 36 WARN_ONCE(1, "%s: skb invalid", __func__); 37 return RX_HANDLER_PASS; 38 } 39 40 port = hsr_port_get_rcu(skb->dev); 41 if (!port) 42 goto finish_pass; 43 hsr = port->hsr; 44 45 if (hsr_addr_is_self(port->hsr, eth_hdr(skb)->h_source)) { 46 /* Directly kill frames sent by ourselves */ 47 kfree_skb(skb); 48 goto finish_consume; 49 } 50 51 /* For HSR, only tagged frames are expected, but for PRP 52 * there could be non tagged frames as well from Single 53 * attached nodes (SANs). 54 */ 55 protocol = eth_hdr(skb)->h_proto; 56 if (hsr->proto_ops->invalid_dan_ingress_frame && 57 hsr->proto_ops->invalid_dan_ingress_frame(protocol)) 58 goto finish_pass; 59 60 skb_push(skb, ETH_HLEN); 61 skb_reset_mac_header(skb); 62 if ((!hsr->prot_version && protocol == htons(ETH_P_PRP)) || 63 protocol == htons(ETH_P_HSR)) 64 skb_set_network_header(skb, ETH_HLEN + HSR_HLEN); 65 skb_reset_mac_len(skb); 66 67 hsr_forward_skb(skb, port); 68 69finish_consume: 70 return RX_HANDLER_CONSUMED; 71 72finish_pass: 73 return RX_HANDLER_PASS; 74} 75 76bool hsr_port_exists(const struct net_device *dev) 77{ 78 return rcu_access_pointer(dev->rx_handler) == hsr_handle_frame; 79} 80 81static int hsr_check_dev_ok(struct net_device *dev, 82 struct netlink_ext_ack *extack) 83{ 84 /* Don't allow HSR on non-ethernet like devices */ 85 if ((dev->flags & IFF_LOOPBACK) || dev->type != ARPHRD_ETHER || 86 dev->addr_len != ETH_ALEN) { 87 NL_SET_ERR_MSG_MOD(extack, "Cannot use loopback or non-ethernet device as HSR slave."); 88 return -EINVAL; 89 } 90 91 /* Don't allow enslaving hsr devices */ 92 if (is_hsr_master(dev)) { 93 NL_SET_ERR_MSG_MOD(extack, 94 "Cannot create trees of HSR devices."); 95 return -EINVAL; 96 } 97 98 if (hsr_port_exists(dev)) { 99 NL_SET_ERR_MSG_MOD(extack, 100 "This device is already a HSR slave."); 101 return -EINVAL; 102 } 103 104 if (is_vlan_dev(dev)) { 105 NL_SET_ERR_MSG_MOD(extack, "HSR on top of VLAN is not yet supported in this driver."); 106 return -EINVAL; 107 } 108 109 if (dev->priv_flags & IFF_DONT_BRIDGE) { 110 NL_SET_ERR_MSG_MOD(extack, 111 "This device does not support bridging."); 112 return -EOPNOTSUPP; 113 } 114 115 /* HSR over bonded devices has not been tested, but I'm not sure it 116 * won't work... 117 */ 118 119 return 0; 120} 121 122/* Setup device to be added to the HSR bridge. */ 123static int hsr_portdev_setup(struct hsr_priv *hsr, struct net_device *dev, 124 struct hsr_port *port, 125 struct netlink_ext_ack *extack) 126 127{ 128 struct net_device *hsr_dev; 129 struct hsr_port *master; 130 int res; 131 132 res = dev_set_promiscuity(dev, 1); 133 if (res) 134 return res; 135 136 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 137 hsr_dev = master->dev; 138 139 res = netdev_upper_dev_link(dev, hsr_dev, extack); 140 if (res) 141 goto fail_upper_dev_link; 142 143 res = netdev_rx_handler_register(dev, hsr_handle_frame, port); 144 if (res) 145 goto fail_rx_handler; 146 dev_disable_lro(dev); 147 148 return 0; 149 150fail_rx_handler: 151 netdev_upper_dev_unlink(dev, hsr_dev); 152fail_upper_dev_link: 153 dev_set_promiscuity(dev, -1); 154 return res; 155} 156 157int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev, 158 enum hsr_port_type type, struct netlink_ext_ack *extack) 159{ 160 struct hsr_port *port, *master; 161 int res; 162 163 if (type != HSR_PT_MASTER) { 164 res = hsr_check_dev_ok(dev, extack); 165 if (res) 166 return res; 167 } 168 169 port = hsr_port_get_hsr(hsr, type); 170 if (port) 171 return -EBUSY; /* This port already exists */ 172 173 port = kzalloc(sizeof(*port), GFP_KERNEL); 174 if (!port) 175 return -ENOMEM; 176 177 port->hsr = hsr; 178 port->dev = dev; 179 port->type = type; 180 181 if (type != HSR_PT_MASTER) { 182 res = hsr_portdev_setup(hsr, dev, port, extack); 183 if (res) 184 goto fail_dev_setup; 185 } 186 187 list_add_tail_rcu(&port->port_list, &hsr->ports); 188 synchronize_rcu(); 189 190 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 191 netdev_update_features(master->dev); 192 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 193 194 return 0; 195 196fail_dev_setup: 197 kfree(port); 198 return res; 199} 200 201void hsr_del_port(struct hsr_port *port) 202{ 203 struct hsr_priv *hsr; 204 struct hsr_port *master; 205 206 hsr = port->hsr; 207 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 208 list_del_rcu(&port->port_list); 209 210 if (port != master) { 211 netdev_update_features(master->dev); 212 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 213 netdev_rx_handler_unregister(port->dev); 214 dev_set_promiscuity(port->dev, -1); 215 netdev_upper_dev_unlink(port->dev, master->dev); 216 } 217 218 synchronize_rcu(); 219 220 kfree(port); 221} 222