1 /*
2  * Copyright (c) 2016 Chelsio Communications, Inc. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *	  copyright notice, this list of conditions and the following
16  *	  disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *	  copyright notice, this list of conditions and the following
20  *	  disclaimer in the documentation and/or other materials
21  *	  provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <linux/tcp.h>
34 #include <linux/ipv6.h>
35 #include <net/route.h>
36 #include <net/ip6_route.h>
37 
38 #include "libcxgb_cm.h"
39 
40 void
41 cxgb_get_4tuple(struct cpl_pass_accept_req *req, enum chip_type type,
42 		int *iptype, __u8 *local_ip, __u8 *peer_ip,
43 		__be16 *local_port, __be16 *peer_port)
44 {
45 	int eth_len = (CHELSIO_CHIP_VERSION(type) <= CHELSIO_T5) ?
46 		      ETH_HDR_LEN_G(be32_to_cpu(req->hdr_len)) :
47 		      T6_ETH_HDR_LEN_G(be32_to_cpu(req->hdr_len));
48 	int ip_len = (CHELSIO_CHIP_VERSION(type) <= CHELSIO_T5) ?
49 		     IP_HDR_LEN_G(be32_to_cpu(req->hdr_len)) :
50 		     T6_IP_HDR_LEN_G(be32_to_cpu(req->hdr_len));
51 	struct iphdr *ip = (struct iphdr *)((u8 *)(req + 1) + eth_len);
52 	struct ipv6hdr *ip6 = (struct ipv6hdr *)((u8 *)(req + 1) + eth_len);
53 	struct tcphdr *tcp = (struct tcphdr *)
54 			     ((u8 *)(req + 1) + eth_len + ip_len);
55 
56 	if (ip->version == 4) {
57 		pr_debug("%s saddr 0x%x daddr 0x%x sport %u dport %u\n",
58 			 __func__, ntohl(ip->saddr), ntohl(ip->daddr),
59 			 ntohs(tcp->source), ntohs(tcp->dest));
60 		*iptype = 4;
61 		memcpy(peer_ip, &ip->saddr, 4);
62 		memcpy(local_ip, &ip->daddr, 4);
63 	} else {
64 		pr_debug("%s saddr %pI6 daddr %pI6 sport %u dport %u\n",
65 			 __func__, ip6->saddr.s6_addr, ip6->daddr.s6_addr,
66 			 ntohs(tcp->source), ntohs(tcp->dest));
67 		*iptype = 6;
68 		memcpy(peer_ip, ip6->saddr.s6_addr, 16);
69 		memcpy(local_ip, ip6->daddr.s6_addr, 16);
70 	}
71 	*peer_port = tcp->source;
72 	*local_port = tcp->dest;
73 }
74 EXPORT_SYMBOL(cxgb_get_4tuple);
75 
76 static bool
77 cxgb_our_interface(struct cxgb4_lld_info *lldi,
78 		   struct net_device *(*get_real_dev)(struct net_device *),
79 		   struct net_device *egress_dev)
80 {
81 	int i;
82 
83 	egress_dev = get_real_dev(egress_dev);
84 	for (i = 0; i < lldi->nports; i++)
85 		if (lldi->ports[i] == egress_dev)
86 			return true;
87 	return false;
88 }
89 
90 struct dst_entry *
91 cxgb_find_route(struct cxgb4_lld_info *lldi,
92 		struct net_device *(*get_real_dev)(struct net_device *),
93 		__be32 local_ip, __be32 peer_ip, __be16 local_port,
94 		__be16 peer_port, u8 tos)
95 {
96 	struct rtable *rt;
97 	struct flowi4 fl4;
98 	struct neighbour *n;
99 
100 	rt = ip_route_output_ports(&init_net, &fl4, NULL, peer_ip, local_ip,
101 				   peer_port, local_port, IPPROTO_TCP,
102 				   tos, 0);
103 	if (IS_ERR(rt))
104 		return NULL;
105 	n = dst_neigh_lookup(&rt->dst, &peer_ip);
106 	if (!n)
107 		return NULL;
108 	if (!cxgb_our_interface(lldi, get_real_dev, n->dev) &&
109 	    !(n->dev->flags & IFF_LOOPBACK)) {
110 		neigh_release(n);
111 		dst_release(&rt->dst);
112 		return NULL;
113 	}
114 	neigh_release(n);
115 	return &rt->dst;
116 }
117 EXPORT_SYMBOL(cxgb_find_route);
118 
119 struct dst_entry *
120 cxgb_find_route6(struct cxgb4_lld_info *lldi,
121 		 struct net_device *(*get_real_dev)(struct net_device *),
122 		 __u8 *local_ip, __u8 *peer_ip, __be16 local_port,
123 		 __be16 peer_port, u8 tos, __u32 sin6_scope_id)
124 {
125 	struct dst_entry *dst = NULL;
126 
127 	if (IS_ENABLED(CONFIG_IPV6)) {
128 		struct flowi6 fl6;
129 
130 		memset(&fl6, 0, sizeof(fl6));
131 		memcpy(&fl6.daddr, peer_ip, 16);
132 		memcpy(&fl6.saddr, local_ip, 16);
133 		if (ipv6_addr_type(&fl6.daddr) & IPV6_ADDR_LINKLOCAL)
134 			fl6.flowi6_oif = sin6_scope_id;
135 		dst = ip6_route_output(&init_net, NULL, &fl6);
136 		if (dst->error ||
137 		    (!cxgb_our_interface(lldi, get_real_dev,
138 					 ip6_dst_idev(dst)->dev) &&
139 		     !(ip6_dst_idev(dst)->dev->flags & IFF_LOOPBACK))) {
140 			dst_release(dst);
141 			return NULL;
142 		}
143 	}
144 
145 	return dst;
146 }
147 EXPORT_SYMBOL(cxgb_find_route6);
148