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 if (!pskb_may_pull(skb, ETH_HLEN + HSR_HLEN)) { 68 kfree_skb(skb); 69 goto finish_consume; 70 } 71 72 skb_set_network_header(skb, ETH_HLEN + HSR_HLEN); 73 } 74 skb_reset_mac_len(skb); 75 76 /* Only the frames received over the interlink port will assign a 77 * sequence number and require synchronisation vs other sender. 78 */ 79 if (port->type == HSR_PT_INTERLINK) { 80 spin_lock_bh(&hsr->seqnr_lock); 81 hsr_forward_skb(skb, port); 82 spin_unlock_bh(&hsr->seqnr_lock); 83 } else { 84 hsr_forward_skb(skb, port); 85 } 86 87 finish_consume: 88 return RX_HANDLER_CONSUMED; 89 90 finish_pass: 91 return RX_HANDLER_PASS; 92 } 93 94 bool hsr_port_exists(const struct net_device *dev) 95 { 96 return rcu_access_pointer(dev->rx_handler) == hsr_handle_frame; 97 } 98 99 static int hsr_check_dev_ok(struct net_device *dev, 100 struct netlink_ext_ack *extack) 101 { 102 /* Don't allow HSR on non-ethernet like devices */ 103 if ((dev->flags & IFF_LOOPBACK) || dev->type != ARPHRD_ETHER || 104 dev->addr_len != ETH_ALEN) { 105 NL_SET_ERR_MSG_MOD(extack, "Cannot use loopback or non-ethernet device as HSR slave."); 106 return -EINVAL; 107 } 108 109 /* Don't allow enslaving hsr devices */ 110 if (is_hsr_master(dev)) { 111 NL_SET_ERR_MSG_MOD(extack, 112 "Cannot create trees of HSR devices."); 113 return -EINVAL; 114 } 115 116 if (hsr_port_exists(dev)) { 117 NL_SET_ERR_MSG_MOD(extack, 118 "This device is already a HSR slave."); 119 return -EINVAL; 120 } 121 122 if (is_vlan_dev(dev)) { 123 NL_SET_ERR_MSG_MOD(extack, "HSR on top of VLAN is not yet supported in this driver."); 124 return -EINVAL; 125 } 126 127 if (dev->priv_flags & IFF_DONT_BRIDGE) { 128 NL_SET_ERR_MSG_MOD(extack, 129 "This device does not support bridging."); 130 return -EOPNOTSUPP; 131 } 132 133 /* HSR over bonded devices has not been tested, but I'm not sure it 134 * won't work... 135 */ 136 137 return 0; 138 } 139 140 /* Setup device to be added to the HSR bridge. */ 141 static int hsr_portdev_setup(struct hsr_priv *hsr, struct net_device *dev, 142 struct hsr_port *port, 143 struct netlink_ext_ack *extack) 144 145 { 146 struct net_device *hsr_dev; 147 struct hsr_port *master; 148 int res; 149 150 /* Don't use promiscuous mode for offload since L2 frame forward 151 * happens at the offloaded hardware. 152 */ 153 if (!port->hsr->fwd_offloaded) { 154 res = dev_set_promiscuity(dev, 1); 155 if (res) 156 return res; 157 } 158 159 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 160 hsr_dev = master->dev; 161 162 res = netdev_upper_dev_link(dev, hsr_dev, extack); 163 if (res) 164 goto fail_upper_dev_link; 165 166 res = netdev_rx_handler_register(dev, hsr_handle_frame, port); 167 if (res) 168 goto fail_rx_handler; 169 dev_disable_lro(dev); 170 171 return 0; 172 173 fail_rx_handler: 174 netdev_upper_dev_unlink(dev, hsr_dev); 175 fail_upper_dev_link: 176 if (!port->hsr->fwd_offloaded) 177 dev_set_promiscuity(dev, -1); 178 179 return res; 180 } 181 182 int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev, 183 enum hsr_port_type type, struct netlink_ext_ack *extack) 184 { 185 struct hsr_port *port, *master; 186 int res; 187 188 if (type != HSR_PT_MASTER) { 189 res = hsr_check_dev_ok(dev, extack); 190 if (res) 191 return res; 192 } 193 194 port = hsr_port_get_hsr(hsr, type); 195 if (port) 196 return -EBUSY; /* This port already exists */ 197 198 port = kzalloc(sizeof(*port), GFP_KERNEL); 199 if (!port) 200 return -ENOMEM; 201 202 port->hsr = hsr; 203 port->dev = dev; 204 port->type = type; 205 ether_addr_copy(port->original_macaddress, dev->dev_addr); 206 207 if (type != HSR_PT_MASTER) { 208 res = hsr_portdev_setup(hsr, dev, port, extack); 209 if (res) 210 goto fail_dev_setup; 211 } 212 213 list_add_tail_rcu(&port->port_list, &hsr->ports); 214 215 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 216 netdev_update_features(master->dev); 217 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 218 219 return 0; 220 221 fail_dev_setup: 222 kfree(port); 223 return res; 224 } 225 226 void hsr_del_port(struct hsr_port *port) 227 { 228 struct hsr_priv *hsr; 229 struct hsr_port *master; 230 231 hsr = port->hsr; 232 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 233 list_del_rcu(&port->port_list); 234 235 if (port != master) { 236 netdev_update_features(master->dev); 237 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 238 netdev_rx_handler_unregister(port->dev); 239 if (!port->hsr->fwd_offloaded) 240 dev_set_promiscuity(port->dev, -1); 241 netdev_upper_dev_unlink(port->dev, master->dev); 242 eth_hw_addr_set(port->dev, port->original_macaddress); 243 } 244 245 kfree_rcu(port, rcu); 246 } 247