libcxgb_cm.c

  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/inet_ecn.h>
 36#include <net/route.h>
 37#include <net/ip6_route.h>
 38
 39#include "libcxgb_cm.h"
 40
 41void
 42cxgb_get_4tuple(struct cpl_pass_accept_req *req, enum chip_type type,
 43		int *iptype, __u8 *local_ip, __u8 *peer_ip,
 44		__be16 *local_port, __be16 *peer_port)
 45{
 46	int eth_len = (CHELSIO_CHIP_VERSION(type) <= CHELSIO_T5) ?
 47		      ETH_HDR_LEN_G(be32_to_cpu(req->hdr_len)) :
 48		      T6_ETH_HDR_LEN_G(be32_to_cpu(req->hdr_len));
 49	int ip_len = (CHELSIO_CHIP_VERSION(type) <= CHELSIO_T5) ?
 50		     IP_HDR_LEN_G(be32_to_cpu(req->hdr_len)) :
 51		     T6_IP_HDR_LEN_G(be32_to_cpu(req->hdr_len));
 52	struct iphdr *ip = (struct iphdr *)((u8 *)(req + 1) + eth_len);
 53	struct ipv6hdr *ip6 = (struct ipv6hdr *)((u8 *)(req + 1) + eth_len);
 54	struct tcphdr *tcp = (struct tcphdr *)
 55			     ((u8 *)(req + 1) + eth_len + ip_len);
 56
 57	if (ip->version == 4) {
 58		pr_debug("%s saddr 0x%x daddr 0x%x sport %u dport %u\n",
 59			 __func__, ntohl(ip->saddr), ntohl(ip->daddr),
 60			 ntohs(tcp->source), ntohs(tcp->dest));
 61		*iptype = 4;
 62		memcpy(peer_ip, &ip->saddr, 4);
 63		memcpy(local_ip, &ip->daddr, 4);
 64	} else {
 65		pr_debug("%s saddr %pI6 daddr %pI6 sport %u dport %u\n",
 66			 __func__, ip6->saddr.s6_addr, ip6->daddr.s6_addr,
 67			 ntohs(tcp->source), ntohs(tcp->dest));
 68		*iptype = 6;
 69		memcpy(peer_ip, ip6->saddr.s6_addr, 16);
 70		memcpy(local_ip, ip6->daddr.s6_addr, 16);
 71	}
 72	*peer_port = tcp->source;
 73	*local_port = tcp->dest;
 74}
 75EXPORT_SYMBOL(cxgb_get_4tuple);
 76
 77static bool
 78cxgb_our_interface(struct cxgb4_lld_info *lldi,
 79		   struct net_device *(*get_real_dev)(struct net_device *),
 80		   struct net_device *egress_dev)
 81{
 82	int i;
 83
 84	egress_dev = get_real_dev(egress_dev);
 85	for (i = 0; i < lldi->nports; i++)
 86		if (lldi->ports[i] == egress_dev)
 87			return true;
 88	return false;
 89}
 90
 91struct dst_entry *
 92cxgb_find_route(struct cxgb4_lld_info *lldi,
 93		struct net_device *(*get_real_dev)(struct net_device *),
 94		__be32 local_ip, __be32 peer_ip, __be16 local_port,
 95		__be16 peer_port, u8 tos)
 96{
 97	struct rtable *rt;
 98	struct flowi4 fl4;
 99	struct neighbour *n;
100
101	rt = ip_route_output_ports(&init_net, &fl4, NULL, peer_ip, local_ip,
102				   peer_port, local_port, IPPROTO_TCP,
103				   tos & ~INET_ECN_MASK, 0);
104	if (IS_ERR(rt))
105		return NULL;
106	n = dst_neigh_lookup(&rt->dst, &peer_ip);
107	if (!n)
108		return NULL;
109	if (!cxgb_our_interface(lldi, get_real_dev, n->dev) &&
110	    !(n->dev->flags & IFF_LOOPBACK)) {
111		neigh_release(n);
112		dst_release(&rt->dst);
113		return NULL;
114	}
115	neigh_release(n);
116	return &rt->dst;
117}
118EXPORT_SYMBOL(cxgb_find_route);
119
120struct dst_entry *
121cxgb_find_route6(struct cxgb4_lld_info *lldi,
122		 struct net_device *(*get_real_dev)(struct net_device *),
123		 __u8 *local_ip, __u8 *peer_ip, __be16 local_port,
124		 __be16 peer_port, u8 tos, __u32 sin6_scope_id)
125{
126	struct dst_entry *dst = NULL;
127
128	if (IS_ENABLED(CONFIG_IPV6)) {
129		struct flowi6 fl6;
130
131		memset(&fl6, 0, sizeof(fl6));
132		memcpy(&fl6.daddr, peer_ip, 16);
133		memcpy(&fl6.saddr, local_ip, 16);
134		if (ipv6_addr_type(&fl6.daddr) & IPV6_ADDR_LINKLOCAL)
135			fl6.flowi6_oif = sin6_scope_id;
136		dst = ip6_route_output(&init_net, NULL, &fl6);
137		if (dst->error ||
138		    (!cxgb_our_interface(lldi, get_real_dev,
139					 ip6_dst_idev(dst)->dev) &&
140		     !(ip6_dst_idev(dst)->dev->flags & IFF_LOOPBACK))) {
141			dst_release(dst);
142			return NULL;
143		}
144	}
145
146	return dst;
147}
148EXPORT_SYMBOL(cxgb_find_route6);