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 64 if (skb_mac_header(skb) != skb->data) { 65 WARN_ONCE(1, "%s:%d: Malformed frame at source port %s)\n", 66 __func__, __LINE__, port->dev->name); 67 goto finish_consume; 68 } 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 res = dev_set_promiscuity(dev, 1); 136 if (res) 137 return res; 138 139 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 140 hsr_dev = master->dev; 141 142 res = netdev_upper_dev_link(dev, hsr_dev, extack); 143 if (res) 144 goto fail_upper_dev_link; 145 146 res = netdev_rx_handler_register(dev, hsr_handle_frame, port); 147 if (res) 148 goto fail_rx_handler; 149 dev_disable_lro(dev); 150 151 return 0; 152 153 fail_rx_handler: 154 netdev_upper_dev_unlink(dev, hsr_dev); 155 fail_upper_dev_link: 156 dev_set_promiscuity(dev, -1); 157 return res; 158 } 159 160 int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev, 161 enum hsr_port_type type, struct netlink_ext_ack *extack) 162 { 163 struct hsr_port *port, *master; 164 int res; 165 166 if (type != HSR_PT_MASTER) { 167 res = hsr_check_dev_ok(dev, extack); 168 if (res) 169 return res; 170 } 171 172 port = hsr_port_get_hsr(hsr, type); 173 if (port) 174 return -EBUSY; /* This port already exists */ 175 176 port = kzalloc(sizeof(*port), GFP_KERNEL); 177 if (!port) 178 return -ENOMEM; 179 180 port->hsr = hsr; 181 port->dev = dev; 182 port->type = type; 183 184 if (type != HSR_PT_MASTER) { 185 res = hsr_portdev_setup(hsr, dev, port, extack); 186 if (res) 187 goto fail_dev_setup; 188 } 189 190 list_add_tail_rcu(&port->port_list, &hsr->ports); 191 synchronize_rcu(); 192 193 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 194 netdev_update_features(master->dev); 195 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 196 197 return 0; 198 199 fail_dev_setup: 200 kfree(port); 201 return res; 202 } 203 204 void hsr_del_port(struct hsr_port *port) 205 { 206 struct hsr_priv *hsr; 207 struct hsr_port *master; 208 209 hsr = port->hsr; 210 master = hsr_port_get_hsr(hsr, HSR_PT_MASTER); 211 list_del_rcu(&port->port_list); 212 213 if (port != master) { 214 netdev_update_features(master->dev); 215 dev_set_mtu(master->dev, hsr_get_max_mtu(hsr)); 216 netdev_rx_handler_unregister(port->dev); 217 dev_set_promiscuity(port->dev, -1); 218 netdev_upper_dev_unlink(port->dev, master->dev); 219 } 220 221 synchronize_rcu(); 222 223 kfree(port); 224 } 225