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 19 bool hsr_invalid_dan_ingress_frame(__be16 protocol) 20 { 21 return (protocol != htons(ETH_P_PRP) && protocol != htons(ETH_P_HSR)); 22 } 23 24 static 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 (unless the device offloads 52 * HSR tag removal), but for PRP there could be non tagged frames as 53 * well from Single attached nodes (SANs). 54 */ 55 protocol = eth_hdr(skb)->h_proto; 56 57 if (!(port->dev->features & NETIF_F_HW_HSR_TAG_RM) && 58 port->type != HSR_PT_INTERLINK && 59 hsr->proto_ops->invalid_dan_ingress_frame && 60 hsr->proto_ops->invalid_dan_ingress_frame(protocol)) 61 goto finish_pass; 62 63 skb_push(skb, ETH_HLEN); 64 skb_reset_mac_header(skb); 65 if ((!hsr->prot_version && protocol == htons(ETH_P_PRP)) || 66 protocol == htons(ETH_P_HSR)) 67 skb_set_network_header(skb, ETH_HLEN + HSR_HLEN); 68 skb_reset_mac_len(skb); 69 70 hsr_forward_skb(skb, port); 71 72 finish_consume: 73 return RX_HANDLER_CONSUMED; 74 75 finish_pass: 76 return RX_HANDLER_PASS; 77 } 78 79 bool hsr_port_exists(const struct net_device *dev) 80 { 81 return rcu_access_pointer(dev->rx_handler) == hsr_handle_frame; 82 } 83 84 static int hsr_check_dev_ok(struct net_device *dev, 85 struct netlink_ext_ack *extack) 86 { 87 /* Don't allow HSR on non-ethernet like devices */ 88 if ((dev->flags & IFF_LOOPBACK) || dev->type != ARPHRD_ETHER || 89 dev->addr_len != ETH_ALEN) { 90 NL_SET_ERR_MSG_MOD(extack, "Cannot use loopback or non-ethernet device as HSR slave."); 91 return -EINVAL; 92 } 93 94 /* Don't allow enslaving hsr devices */ 95 if (is_hsr_master(dev)) { 96 NL_SET_ERR_MSG_MOD(extack, 97 "Cannot create trees of HSR devices."); 98 return -EINVAL; 99 } 100 101 if (hsr_port_exists(dev)) { 102 NL_SET_ERR_MSG_MOD(extack, 103 "This device is already a HSR slave."); 104 return -EINVAL; 105 } 106 107 if (is_vlan_dev(dev)) { 108 NL_SET_ERR_MSG_MOD(extack, "HSR on top of VLAN is not yet supported in this driver."); 109 return -EINVAL; 110 } 111 112 if (dev->priv_flags & IFF_DONT_BRIDGE) { 113 NL_SET_ERR_MSG_MOD(extack, 114 "This device does not support bridging."); 115 return -EOPNOTSUPP; 116 } 117 118 /* HSR over bonded devices has not been tested, but I'm not sure it 119 * won't work... 120 */ 121 122 return 0; 123 } 124 125 /* Setup device to be added to the HSR bridge. */ 126 static int hsr_portdev_setup(struct hsr_priv *hsr, struct net_device *dev, 127 struct hsr_port *port, 128 struct netlink_ext_ack *extack) 129 130 { 131 struct net_device *hsr_dev; 132 struct hsr_port *master; 133 int res; 134 135 /* Don't use promiscuous mode for offload since L2 frame forward 136 * happens at the offloaded hardware. 137 */ 138 if (!port->hsr->fwd_offloaded) { 139 res = dev_set_promiscuity(dev, 1); 140 if (res) 141 return res; 142 } 143 144 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 145 hsr_dev = master->dev; 146 147 res = netdev_upper_dev_link(dev, hsr_dev, extack); 148 if (res) 149 goto fail_upper_dev_link; 150 151 res = netdev_rx_handler_register(dev, hsr_handle_frame, port); 152 if (res) 153 goto fail_rx_handler; 154 dev_disable_lro(dev); 155 156 return 0; 157 158 fail_rx_handler: 159 netdev_upper_dev_unlink(dev, hsr_dev); 160 fail_upper_dev_link: 161 if (!port->hsr->fwd_offloaded) 162 dev_set_promiscuity(dev, -1); 163 164 return res; 165 } 166 167 int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev, 168 enum hsr_port_type type, struct netlink_ext_ack *extack) 169 { 170 struct hsr_port *port, *master; 171 int res; 172 173 if (type != HSR_PT_MASTER) { 174 res = hsr_check_dev_ok(dev, extack); 175 if (res) 176 return res; 177 } 178 179 port = hsr_port_get_hsr(hsr, type); 180 if (port) 181 return -EBUSY; /* This port already exists */ 182 183 port = kzalloc(sizeof(*port), GFP_KERNEL); 184 if (!port) 185 return -ENOMEM; 186 187 port->hsr = hsr; 188 port->dev = dev; 189 port->type = type; 190 191 if (type != HSR_PT_MASTER) { 192 res = hsr_portdev_setup(hsr, dev, port, extack); 193 if (res) 194 goto fail_dev_setup; 195 } 196 197 list_add_tail_rcu(&port->port_list, &hsr->ports); 198 synchronize_rcu(); 199 200 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 201 netdev_update_features(master->dev); 202 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 203 204 return 0; 205 206 fail_dev_setup: 207 kfree(port); 208 return res; 209 } 210 211 void hsr_del_port(struct hsr_port *port) 212 { 213 struct hsr_priv *hsr; 214 struct hsr_port *master; 215 216 hsr = port->hsr; 217 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 218 list_del_rcu(&port->port_list); 219 220 if (port != master) { 221 netdev_update_features(master->dev); 222 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 223 netdev_rx_handler_unregister(port->dev); 224 if (!port->hsr->fwd_offloaded) 225 dev_set_promiscuity(port->dev, -1); 226 netdev_upper_dev_unlink(port->dev, master->dev); 227 } 228 229 synchronize_rcu(); 230 231 kfree(port); 232 } 233