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