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 /* Only the frames received over the interlink port will assign a 71 * sequence number and require synchronisation vs other sender. 72 */ 73 if (port->type == HSR_PT_INTERLINK) { 74 spin_lock_bh(&hsr->seqnr_lock); 75 hsr_forward_skb(skb, port); 76 spin_unlock_bh(&hsr->seqnr_lock); 77 } else { 78 hsr_forward_skb(skb, port); 79 } 80 81 finish_consume: 82 return RX_HANDLER_CONSUMED; 83 84 finish_pass: 85 return RX_HANDLER_PASS; 86 } 87 88 bool hsr_port_exists(const struct net_device *dev) 89 { 90 return rcu_access_pointer(dev->rx_handler) == hsr_handle_frame; 91 } 92 93 static int hsr_check_dev_ok(struct net_device *dev, 94 struct netlink_ext_ack *extack) 95 { 96 /* Don't allow HSR on non-ethernet like devices */ 97 if ((dev->flags & IFF_LOOPBACK) || dev->type != ARPHRD_ETHER || 98 dev->addr_len != ETH_ALEN) { 99 NL_SET_ERR_MSG_MOD(extack, "Cannot use loopback or non-ethernet device as HSR slave."); 100 return -EINVAL; 101 } 102 103 /* Don't allow enslaving hsr devices */ 104 if (is_hsr_master(dev)) { 105 NL_SET_ERR_MSG_MOD(extack, 106 "Cannot create trees of HSR devices."); 107 return -EINVAL; 108 } 109 110 if (hsr_port_exists(dev)) { 111 NL_SET_ERR_MSG_MOD(extack, 112 "This device is already a HSR slave."); 113 return -EINVAL; 114 } 115 116 if (is_vlan_dev(dev)) { 117 NL_SET_ERR_MSG_MOD(extack, "HSR on top of VLAN is not yet supported in this driver."); 118 return -EINVAL; 119 } 120 121 if (dev->priv_flags & IFF_DONT_BRIDGE) { 122 NL_SET_ERR_MSG_MOD(extack, 123 "This device does not support bridging."); 124 return -EOPNOTSUPP; 125 } 126 127 /* HSR over bonded devices has not been tested, but I'm not sure it 128 * won't work... 129 */ 130 131 return 0; 132 } 133 134 /* Setup device to be added to the HSR bridge. */ 135 static int hsr_portdev_setup(struct hsr_priv *hsr, struct net_device *dev, 136 struct hsr_port *port, 137 struct netlink_ext_ack *extack) 138 139 { 140 struct net_device *hsr_dev; 141 struct hsr_port *master; 142 int res; 143 144 /* Don't use promiscuous mode for offload since L2 frame forward 145 * happens at the offloaded hardware. 146 */ 147 if (!port->hsr->fwd_offloaded) { 148 res = dev_set_promiscuity(dev, 1); 149 if (res) 150 return res; 151 } 152 153 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 154 hsr_dev = master->dev; 155 156 res = netdev_upper_dev_link(dev, hsr_dev, extack); 157 if (res) 158 goto fail_upper_dev_link; 159 160 res = netdev_rx_handler_register(dev, hsr_handle_frame, port); 161 if (res) 162 goto fail_rx_handler; 163 dev_disable_lro(dev); 164 165 return 0; 166 167 fail_rx_handler: 168 netdev_upper_dev_unlink(dev, hsr_dev); 169 fail_upper_dev_link: 170 if (!port->hsr->fwd_offloaded) 171 dev_set_promiscuity(dev, -1); 172 173 return res; 174 } 175 176 int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev, 177 enum hsr_port_type type, struct netlink_ext_ack *extack) 178 { 179 struct hsr_port *port, *master; 180 int res; 181 182 if (type != HSR_PT_MASTER) { 183 res = hsr_check_dev_ok(dev, extack); 184 if (res) 185 return res; 186 } 187 188 port = hsr_port_get_hsr(hsr, type); 189 if (port) 190 return -EBUSY; /* This port already exists */ 191 192 port = kzalloc(sizeof(*port), GFP_KERNEL); 193 if (!port) 194 return -ENOMEM; 195 196 port->hsr = hsr; 197 port->dev = dev; 198 port->type = type; 199 200 if (type != HSR_PT_MASTER) { 201 res = hsr_portdev_setup(hsr, dev, port, extack); 202 if (res) 203 goto fail_dev_setup; 204 } 205 206 list_add_tail_rcu(&port->port_list, &hsr->ports); 207 synchronize_rcu(); 208 209 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 210 netdev_update_features(master->dev); 211 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 212 213 return 0; 214 215 fail_dev_setup: 216 kfree(port); 217 return res; 218 } 219 220 void hsr_del_port(struct hsr_port *port) 221 { 222 struct hsr_priv *hsr; 223 struct hsr_port *master; 224 225 hsr = port->hsr; 226 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 227 list_del_rcu(&port->port_list); 228 229 if (port != master) { 230 netdev_update_features(master->dev); 231 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 232 netdev_rx_handler_unregister(port->dev); 233 if (!port->hsr->fwd_offloaded) 234 dev_set_promiscuity(port->dev, -1); 235 netdev_upper_dev_unlink(port->dev, master->dev); 236 } 237 238 synchronize_rcu(); 239 240 kfree(port); 241 } 242