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120f1c857a
The following splat is easy to reproduce upstream as well as in -stable kernels. Florian Westphal provided the following commit:d1dab4f71d
("net: add and use __skb_get_hash_symmetric_net") but this complementary fix has been also suggested by Willem de Bruijn and it can be easily backported to -stable kernel which consists in using DEBUG_NET_WARN_ON_ONCE instead to silence the following splat given __skb_get_hash() is used by the nftables tracing infrastructure to to identify packets in traces. [69133.561393] ------------[ cut here ]------------ [69133.561404] WARNING: CPU: 0 PID: 43576 at net/core/flow_dissector.c:1104 __skb_flow_dissect+0x134f/ [...] [69133.561944] CPU: 0 PID: 43576 Comm: socat Not tainted 6.10.0-rc7+ #379 [69133.561959] RIP: 0010:__skb_flow_dissect+0x134f/0x2ad0 [69133.561970] Code: 83 f9 04 0f 84 b3 00 00 00 45 85 c9 0f 84 aa 00 00 00 41 83 f9 02 0f 84 81 fc ff ff 44 0f b7 b4 24 80 00 00 00 e9 8b f9 ff ff <0f> 0b e9 20 f3 ff ff 41 f6 c6 20 0f 84 e4 ef ff ff 48 8d 7b 12 e8 [69133.561979] RSP: 0018:ffffc90000006fc0 EFLAGS: 00010246 [69133.561988] RAX: 0000000000000000 RBX: ffffffff82f33e20 RCX: ffffffff81ab7e19 [69133.561994] RDX: dffffc0000000000 RSI: ffffc90000007388 RDI: ffff888103a1b418 [69133.562001] RBP: ffffc90000007310 R08: 0000000000000000 R09: 0000000000000000 [69133.562007] R10: ffffc90000007388 R11: ffffffff810cface R12: ffff888103a1b400 [69133.562013] R13: 0000000000000000 R14: ffffffff82f33e2a R15: ffffffff82f33e28 [69133.562020] FS: 00007f40f7131740(0000) GS:ffff888390800000(0000) knlGS:0000000000000000 [69133.562027] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [69133.562033] CR2: 00007f40f7346ee0 CR3: 000000015d200001 CR4: 00000000001706f0 [69133.562040] Call Trace: [69133.562044] <IRQ> [69133.562049] ? __warn+0x9f/0x1a0 [ 1211.841384] ? __skb_flow_dissect+0x107e/0x2860 [...] [ 1211.841496] ? bpf_flow_dissect+0x160/0x160 [ 1211.841753] __skb_get_hash+0x97/0x280 [ 1211.841765] ? __skb_get_hash_symmetric+0x230/0x230 [ 1211.841776] ? mod_find+0xbf/0xe0 [ 1211.841786] ? get_stack_info_noinstr+0x12/0xe0 [ 1211.841798] ? bpf_ksym_find+0x56/0xe0 [ 1211.841807] ? __rcu_read_unlock+0x2a/0x70 [ 1211.841819] nft_trace_init+0x1b9/0x1c0 [nf_tables] [ 1211.841895] ? nft_trace_notify+0x830/0x830 [nf_tables] [ 1211.841964] ? get_stack_info+0x2b/0x80 [ 1211.841975] ? nft_do_chain_arp+0x80/0x80 [nf_tables] [ 1211.842044] nft_do_chain+0x79c/0x850 [nf_tables] Fixes:9b52e3f267
("flow_dissector: handle no-skb use case") Suggested-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20240715141442.43775-1-pablo@netfilter.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2092 lines
56 KiB
C
2092 lines
56 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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#include <linux/kernel.h>
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#include <linux/skbuff.h>
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#include <linux/export.h>
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#include <linux/ip.h>
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#include <linux/ipv6.h>
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#include <linux/if_vlan.h>
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#include <linux/filter.h>
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#include <net/dsa.h>
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#include <net/dst_metadata.h>
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#include <net/ip.h>
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#include <net/ipv6.h>
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#include <net/gre.h>
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#include <net/pptp.h>
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#include <net/tipc.h>
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#include <linux/igmp.h>
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#include <linux/icmp.h>
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#include <linux/sctp.h>
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#include <linux/dccp.h>
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#include <linux/if_tunnel.h>
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#include <linux/if_pppox.h>
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#include <linux/ppp_defs.h>
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#include <linux/stddef.h>
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#include <linux/if_ether.h>
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#include <linux/if_hsr.h>
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#include <linux/mpls.h>
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#include <linux/tcp.h>
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#include <linux/ptp_classify.h>
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#include <net/flow_dissector.h>
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#include <net/pkt_cls.h>
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#include <scsi/fc/fc_fcoe.h>
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#include <uapi/linux/batadv_packet.h>
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#include <linux/bpf.h>
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#if IS_ENABLED(CONFIG_NF_CONNTRACK)
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#include <net/netfilter/nf_conntrack_core.h>
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#include <net/netfilter/nf_conntrack_labels.h>
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#endif
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#include <linux/bpf-netns.h>
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static void dissector_set_key(struct flow_dissector *flow_dissector,
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enum flow_dissector_key_id key_id)
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{
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flow_dissector->used_keys |= (1ULL << key_id);
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}
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void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
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const struct flow_dissector_key *key,
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unsigned int key_count)
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{
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unsigned int i;
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memset(flow_dissector, 0, sizeof(*flow_dissector));
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for (i = 0; i < key_count; i++, key++) {
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/* User should make sure that every key target offset is within
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* boundaries of unsigned short.
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*/
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BUG_ON(key->offset > USHRT_MAX);
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BUG_ON(dissector_uses_key(flow_dissector,
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key->key_id));
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dissector_set_key(flow_dissector, key->key_id);
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flow_dissector->offset[key->key_id] = key->offset;
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}
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/* Ensure that the dissector always includes control and basic key.
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* That way we are able to avoid handling lack of these in fast path.
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*/
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BUG_ON(!dissector_uses_key(flow_dissector,
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FLOW_DISSECTOR_KEY_CONTROL));
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BUG_ON(!dissector_uses_key(flow_dissector,
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FLOW_DISSECTOR_KEY_BASIC));
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}
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EXPORT_SYMBOL(skb_flow_dissector_init);
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#ifdef CONFIG_BPF_SYSCALL
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int flow_dissector_bpf_prog_attach_check(struct net *net,
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struct bpf_prog *prog)
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{
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enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
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if (net == &init_net) {
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/* BPF flow dissector in the root namespace overrides
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* any per-net-namespace one. When attaching to root,
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* make sure we don't have any BPF program attached
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* to the non-root namespaces.
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*/
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struct net *ns;
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for_each_net(ns) {
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if (ns == &init_net)
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continue;
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if (rcu_access_pointer(ns->bpf.run_array[type]))
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return -EEXIST;
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}
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} else {
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/* Make sure root flow dissector is not attached
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* when attaching to the non-root namespace.
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*/
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if (rcu_access_pointer(init_net.bpf.run_array[type]))
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return -EEXIST;
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}
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return 0;
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}
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#endif /* CONFIG_BPF_SYSCALL */
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/**
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* __skb_flow_get_ports - extract the upper layer ports and return them
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* @skb: sk_buff to extract the ports from
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* @thoff: transport header offset
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* @ip_proto: protocol for which to get port offset
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* @data: raw buffer pointer to the packet, if NULL use skb->data
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* @hlen: packet header length, if @data is NULL use skb_headlen(skb)
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*
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* The function will try to retrieve the ports at offset thoff + poff where poff
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* is the protocol port offset returned from proto_ports_offset
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*/
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__be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
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const void *data, int hlen)
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{
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int poff = proto_ports_offset(ip_proto);
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if (!data) {
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data = skb->data;
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hlen = skb_headlen(skb);
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}
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if (poff >= 0) {
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__be32 *ports, _ports;
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ports = __skb_header_pointer(skb, thoff + poff,
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sizeof(_ports), data, hlen, &_ports);
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if (ports)
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return *ports;
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}
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return 0;
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}
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EXPORT_SYMBOL(__skb_flow_get_ports);
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static bool icmp_has_id(u8 type)
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{
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switch (type) {
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case ICMP_ECHO:
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case ICMP_ECHOREPLY:
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case ICMP_TIMESTAMP:
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case ICMP_TIMESTAMPREPLY:
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case ICMPV6_ECHO_REQUEST:
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case ICMPV6_ECHO_REPLY:
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return true;
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}
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return false;
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}
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/**
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* skb_flow_get_icmp_tci - extract ICMP(6) Type, Code and Identifier fields
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* @skb: sk_buff to extract from
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* @key_icmp: struct flow_dissector_key_icmp to fill
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* @data: raw buffer pointer to the packet
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* @thoff: offset to extract at
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* @hlen: packet header length
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*/
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void skb_flow_get_icmp_tci(const struct sk_buff *skb,
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struct flow_dissector_key_icmp *key_icmp,
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const void *data, int thoff, int hlen)
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{
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struct icmphdr *ih, _ih;
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ih = __skb_header_pointer(skb, thoff, sizeof(_ih), data, hlen, &_ih);
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if (!ih)
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return;
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key_icmp->type = ih->type;
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key_icmp->code = ih->code;
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/* As we use 0 to signal that the Id field is not present,
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* avoid confusion with packets without such field
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*/
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if (icmp_has_id(ih->type))
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key_icmp->id = ih->un.echo.id ? ntohs(ih->un.echo.id) : 1;
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else
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key_icmp->id = 0;
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}
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EXPORT_SYMBOL(skb_flow_get_icmp_tci);
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/* If FLOW_DISSECTOR_KEY_ICMP is set, dissect an ICMP packet
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* using skb_flow_get_icmp_tci().
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*/
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static void __skb_flow_dissect_icmp(const struct sk_buff *skb,
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struct flow_dissector *flow_dissector,
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void *target_container, const void *data,
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int thoff, int hlen)
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{
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struct flow_dissector_key_icmp *key_icmp;
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if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ICMP))
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return;
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key_icmp = skb_flow_dissector_target(flow_dissector,
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FLOW_DISSECTOR_KEY_ICMP,
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target_container);
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skb_flow_get_icmp_tci(skb, key_icmp, data, thoff, hlen);
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}
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static void __skb_flow_dissect_ah(const struct sk_buff *skb,
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struct flow_dissector *flow_dissector,
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void *target_container, const void *data,
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int nhoff, int hlen)
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{
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struct flow_dissector_key_ipsec *key_ah;
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struct ip_auth_hdr _hdr, *hdr;
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if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
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return;
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hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
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if (!hdr)
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return;
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key_ah = skb_flow_dissector_target(flow_dissector,
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FLOW_DISSECTOR_KEY_IPSEC,
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target_container);
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key_ah->spi = hdr->spi;
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}
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static void __skb_flow_dissect_esp(const struct sk_buff *skb,
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struct flow_dissector *flow_dissector,
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void *target_container, const void *data,
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int nhoff, int hlen)
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{
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struct flow_dissector_key_ipsec *key_esp;
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struct ip_esp_hdr _hdr, *hdr;
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if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPSEC))
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return;
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hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
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if (!hdr)
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return;
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key_esp = skb_flow_dissector_target(flow_dissector,
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FLOW_DISSECTOR_KEY_IPSEC,
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target_container);
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key_esp->spi = hdr->spi;
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}
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static void __skb_flow_dissect_l2tpv3(const struct sk_buff *skb,
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struct flow_dissector *flow_dissector,
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void *target_container, const void *data,
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int nhoff, int hlen)
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{
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struct flow_dissector_key_l2tpv3 *key_l2tpv3;
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struct {
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__be32 session_id;
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} *hdr, _hdr;
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if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_L2TPV3))
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return;
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hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
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if (!hdr)
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return;
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key_l2tpv3 = skb_flow_dissector_target(flow_dissector,
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FLOW_DISSECTOR_KEY_L2TPV3,
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target_container);
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key_l2tpv3->session_id = hdr->session_id;
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}
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void skb_flow_dissect_meta(const struct sk_buff *skb,
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struct flow_dissector *flow_dissector,
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void *target_container)
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{
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struct flow_dissector_key_meta *meta;
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if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_META))
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return;
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meta = skb_flow_dissector_target(flow_dissector,
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FLOW_DISSECTOR_KEY_META,
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target_container);
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meta->ingress_ifindex = skb->skb_iif;
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#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
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if (tc_skb_ext_tc_enabled()) {
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struct tc_skb_ext *ext;
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ext = skb_ext_find(skb, TC_SKB_EXT);
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if (ext)
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meta->l2_miss = ext->l2_miss;
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}
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#endif
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}
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EXPORT_SYMBOL(skb_flow_dissect_meta);
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static void
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skb_flow_dissect_set_enc_control(enum flow_dissector_key_id type,
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u32 ctrl_flags,
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struct flow_dissector *flow_dissector,
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void *target_container)
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{
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struct flow_dissector_key_control *ctrl;
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if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_CONTROL))
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return;
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ctrl = skb_flow_dissector_target(flow_dissector,
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FLOW_DISSECTOR_KEY_ENC_CONTROL,
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target_container);
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ctrl->addr_type = type;
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ctrl->flags = ctrl_flags;
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}
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void
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skb_flow_dissect_ct(const struct sk_buff *skb,
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struct flow_dissector *flow_dissector,
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void *target_container, u16 *ctinfo_map,
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size_t mapsize, bool post_ct, u16 zone)
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{
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#if IS_ENABLED(CONFIG_NF_CONNTRACK)
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struct flow_dissector_key_ct *key;
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enum ip_conntrack_info ctinfo;
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struct nf_conn_labels *cl;
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struct nf_conn *ct;
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if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CT))
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return;
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ct = nf_ct_get(skb, &ctinfo);
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if (!ct && !post_ct)
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return;
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key = skb_flow_dissector_target(flow_dissector,
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FLOW_DISSECTOR_KEY_CT,
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target_container);
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if (!ct) {
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key->ct_state = TCA_FLOWER_KEY_CT_FLAGS_TRACKED |
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TCA_FLOWER_KEY_CT_FLAGS_INVALID;
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key->ct_zone = zone;
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return;
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}
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if (ctinfo < mapsize)
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key->ct_state = ctinfo_map[ctinfo];
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#if IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)
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key->ct_zone = ct->zone.id;
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#endif
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#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
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key->ct_mark = READ_ONCE(ct->mark);
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#endif
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cl = nf_ct_labels_find(ct);
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if (cl)
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memcpy(key->ct_labels, cl->bits, sizeof(key->ct_labels));
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#endif /* CONFIG_NF_CONNTRACK */
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}
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EXPORT_SYMBOL(skb_flow_dissect_ct);
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void
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skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
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struct flow_dissector *flow_dissector,
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void *target_container)
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{
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struct ip_tunnel_info *info;
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struct ip_tunnel_key *key;
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u32 ctrl_flags = 0;
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/* A quick check to see if there might be something to do. */
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if (!dissector_uses_key(flow_dissector,
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FLOW_DISSECTOR_KEY_ENC_KEYID) &&
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!dissector_uses_key(flow_dissector,
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FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) &&
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!dissector_uses_key(flow_dissector,
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FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS) &&
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!dissector_uses_key(flow_dissector,
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FLOW_DISSECTOR_KEY_ENC_CONTROL) &&
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!dissector_uses_key(flow_dissector,
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FLOW_DISSECTOR_KEY_ENC_PORTS) &&
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!dissector_uses_key(flow_dissector,
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FLOW_DISSECTOR_KEY_ENC_IP) &&
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!dissector_uses_key(flow_dissector,
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FLOW_DISSECTOR_KEY_ENC_OPTS))
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return;
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info = skb_tunnel_info(skb);
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if (!info)
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return;
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key = &info->key;
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if (test_bit(IP_TUNNEL_CSUM_BIT, key->tun_flags))
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ctrl_flags |= FLOW_DIS_F_TUNNEL_CSUM;
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if (test_bit(IP_TUNNEL_DONT_FRAGMENT_BIT, key->tun_flags))
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ctrl_flags |= FLOW_DIS_F_TUNNEL_DONT_FRAGMENT;
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if (test_bit(IP_TUNNEL_OAM_BIT, key->tun_flags))
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ctrl_flags |= FLOW_DIS_F_TUNNEL_OAM;
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if (test_bit(IP_TUNNEL_CRIT_OPT_BIT, key->tun_flags))
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ctrl_flags |= FLOW_DIS_F_TUNNEL_CRIT_OPT;
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switch (ip_tunnel_info_af(info)) {
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case AF_INET:
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skb_flow_dissect_set_enc_control(FLOW_DISSECTOR_KEY_IPV4_ADDRS,
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ctrl_flags, flow_dissector,
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target_container);
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if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS)) {
|
|
struct flow_dissector_key_ipv4_addrs *ipv4;
|
|
|
|
ipv4 = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
|
|
target_container);
|
|
ipv4->src = key->u.ipv4.src;
|
|
ipv4->dst = key->u.ipv4.dst;
|
|
}
|
|
break;
|
|
case AF_INET6:
|
|
skb_flow_dissect_set_enc_control(FLOW_DISSECTOR_KEY_IPV6_ADDRS,
|
|
ctrl_flags, flow_dissector,
|
|
target_container);
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS)) {
|
|
struct flow_dissector_key_ipv6_addrs *ipv6;
|
|
|
|
ipv6 = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS,
|
|
target_container);
|
|
ipv6->src = key->u.ipv6.src;
|
|
ipv6->dst = key->u.ipv6.dst;
|
|
}
|
|
break;
|
|
default:
|
|
skb_flow_dissect_set_enc_control(0, ctrl_flags, flow_dissector,
|
|
target_container);
|
|
break;
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
|
|
struct flow_dissector_key_keyid *keyid;
|
|
|
|
keyid = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ENC_KEYID,
|
|
target_container);
|
|
keyid->keyid = tunnel_id_to_key32(key->tun_id);
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
|
|
struct flow_dissector_key_ports *tp;
|
|
|
|
tp = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ENC_PORTS,
|
|
target_container);
|
|
tp->src = key->tp_src;
|
|
tp->dst = key->tp_dst;
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_IP)) {
|
|
struct flow_dissector_key_ip *ip;
|
|
|
|
ip = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ENC_IP,
|
|
target_container);
|
|
ip->tos = key->tos;
|
|
ip->ttl = key->ttl;
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_OPTS)) {
|
|
struct flow_dissector_key_enc_opts *enc_opt;
|
|
IP_TUNNEL_DECLARE_FLAGS(flags) = { };
|
|
u32 val;
|
|
|
|
enc_opt = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ENC_OPTS,
|
|
target_container);
|
|
|
|
if (!info->options_len)
|
|
return;
|
|
|
|
enc_opt->len = info->options_len;
|
|
ip_tunnel_info_opts_get(enc_opt->data, info);
|
|
|
|
ip_tunnel_set_options_present(flags);
|
|
ip_tunnel_flags_and(flags, info->key.tun_flags, flags);
|
|
|
|
val = find_next_bit(flags, __IP_TUNNEL_FLAG_NUM,
|
|
IP_TUNNEL_GENEVE_OPT_BIT);
|
|
enc_opt->dst_opt_type = val < __IP_TUNNEL_FLAG_NUM ? val : 0;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);
|
|
|
|
void skb_flow_dissect_hash(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container)
|
|
{
|
|
struct flow_dissector_key_hash *key;
|
|
|
|
if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_HASH))
|
|
return;
|
|
|
|
key = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_HASH,
|
|
target_container);
|
|
|
|
key->hash = skb_get_hash_raw(skb);
|
|
}
|
|
EXPORT_SYMBOL(skb_flow_dissect_hash);
|
|
|
|
static enum flow_dissect_ret
|
|
__skb_flow_dissect_mpls(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const void *data, int nhoff,
|
|
int hlen, int lse_index, bool *entropy_label)
|
|
{
|
|
struct mpls_label *hdr, _hdr;
|
|
u32 entry, label, bos;
|
|
|
|
if (!dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
|
|
!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
|
|
if (lse_index >= FLOW_DIS_MPLS_MAX)
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
|
|
hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
|
|
hlen, &_hdr);
|
|
if (!hdr)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
entry = ntohl(hdr->entry);
|
|
label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
|
|
bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
|
|
|
|
if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
|
|
struct flow_dissector_key_mpls *key_mpls;
|
|
struct flow_dissector_mpls_lse *lse;
|
|
|
|
key_mpls = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_MPLS,
|
|
target_container);
|
|
lse = &key_mpls->ls[lse_index];
|
|
|
|
lse->mpls_ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
|
|
lse->mpls_bos = bos;
|
|
lse->mpls_tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
|
|
lse->mpls_label = label;
|
|
dissector_set_mpls_lse(key_mpls, lse_index);
|
|
}
|
|
|
|
if (*entropy_label &&
|
|
dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) {
|
|
struct flow_dissector_key_keyid *key_keyid;
|
|
|
|
key_keyid = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
|
|
target_container);
|
|
key_keyid->keyid = cpu_to_be32(label);
|
|
}
|
|
|
|
*entropy_label = label == MPLS_LABEL_ENTROPY;
|
|
|
|
return bos ? FLOW_DISSECT_RET_OUT_GOOD : FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
}
|
|
|
|
static enum flow_dissect_ret
|
|
__skb_flow_dissect_arp(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const void *data,
|
|
int nhoff, int hlen)
|
|
{
|
|
struct flow_dissector_key_arp *key_arp;
|
|
struct {
|
|
unsigned char ar_sha[ETH_ALEN];
|
|
unsigned char ar_sip[4];
|
|
unsigned char ar_tha[ETH_ALEN];
|
|
unsigned char ar_tip[4];
|
|
} *arp_eth, _arp_eth;
|
|
const struct arphdr *arp;
|
|
struct arphdr _arp;
|
|
|
|
if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
|
|
arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
|
|
hlen, &_arp);
|
|
if (!arp)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
|
|
arp->ar_pro != htons(ETH_P_IP) ||
|
|
arp->ar_hln != ETH_ALEN ||
|
|
arp->ar_pln != 4 ||
|
|
(arp->ar_op != htons(ARPOP_REPLY) &&
|
|
arp->ar_op != htons(ARPOP_REQUEST)))
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
|
|
sizeof(_arp_eth), data,
|
|
hlen, &_arp_eth);
|
|
if (!arp_eth)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
key_arp = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ARP,
|
|
target_container);
|
|
|
|
memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
|
|
memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));
|
|
|
|
/* Only store the lower byte of the opcode;
|
|
* this covers ARPOP_REPLY and ARPOP_REQUEST.
|
|
*/
|
|
key_arp->op = ntohs(arp->ar_op) & 0xff;
|
|
|
|
ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
|
|
ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
|
|
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
}
|
|
|
|
static enum flow_dissect_ret
|
|
__skb_flow_dissect_cfm(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const void *data,
|
|
int nhoff, int hlen)
|
|
{
|
|
struct flow_dissector_key_cfm *key, *hdr, _hdr;
|
|
|
|
if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CFM))
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
|
|
hdr = __skb_header_pointer(skb, nhoff, sizeof(*key), data, hlen, &_hdr);
|
|
if (!hdr)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
key = skb_flow_dissector_target(flow_dissector, FLOW_DISSECTOR_KEY_CFM,
|
|
target_container);
|
|
|
|
key->mdl_ver = hdr->mdl_ver;
|
|
key->opcode = hdr->opcode;
|
|
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
}
|
|
|
|
static enum flow_dissect_ret
|
|
__skb_flow_dissect_gre(const struct sk_buff *skb,
|
|
struct flow_dissector_key_control *key_control,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const void *data,
|
|
__be16 *p_proto, int *p_nhoff, int *p_hlen,
|
|
unsigned int flags)
|
|
{
|
|
struct flow_dissector_key_keyid *key_keyid;
|
|
struct gre_base_hdr *hdr, _hdr;
|
|
int offset = 0;
|
|
u16 gre_ver;
|
|
|
|
hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
|
|
data, *p_hlen, &_hdr);
|
|
if (!hdr)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
/* Only look inside GRE without routing */
|
|
if (hdr->flags & GRE_ROUTING)
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
|
|
/* Only look inside GRE for version 0 and 1 */
|
|
gre_ver = ntohs(hdr->flags & GRE_VERSION);
|
|
if (gre_ver > 1)
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
|
|
*p_proto = hdr->protocol;
|
|
if (gre_ver) {
|
|
/* Version1 must be PPTP, and check the flags */
|
|
if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
}
|
|
|
|
offset += sizeof(struct gre_base_hdr);
|
|
|
|
if (hdr->flags & GRE_CSUM)
|
|
offset += sizeof_field(struct gre_full_hdr, csum) +
|
|
sizeof_field(struct gre_full_hdr, reserved1);
|
|
|
|
if (hdr->flags & GRE_KEY) {
|
|
const __be32 *keyid;
|
|
__be32 _keyid;
|
|
|
|
keyid = __skb_header_pointer(skb, *p_nhoff + offset,
|
|
sizeof(_keyid),
|
|
data, *p_hlen, &_keyid);
|
|
if (!keyid)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_GRE_KEYID)) {
|
|
key_keyid = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_GRE_KEYID,
|
|
target_container);
|
|
if (gre_ver == 0)
|
|
key_keyid->keyid = *keyid;
|
|
else
|
|
key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
|
|
}
|
|
offset += sizeof_field(struct gre_full_hdr, key);
|
|
}
|
|
|
|
if (hdr->flags & GRE_SEQ)
|
|
offset += sizeof_field(struct pptp_gre_header, seq);
|
|
|
|
if (gre_ver == 0) {
|
|
if (*p_proto == htons(ETH_P_TEB)) {
|
|
const struct ethhdr *eth;
|
|
struct ethhdr _eth;
|
|
|
|
eth = __skb_header_pointer(skb, *p_nhoff + offset,
|
|
sizeof(_eth),
|
|
data, *p_hlen, &_eth);
|
|
if (!eth)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
*p_proto = eth->h_proto;
|
|
offset += sizeof(*eth);
|
|
|
|
/* Cap headers that we access via pointers at the
|
|
* end of the Ethernet header as our maximum alignment
|
|
* at that point is only 2 bytes.
|
|
*/
|
|
if (NET_IP_ALIGN)
|
|
*p_hlen = *p_nhoff + offset;
|
|
}
|
|
} else { /* version 1, must be PPTP */
|
|
u8 _ppp_hdr[PPP_HDRLEN];
|
|
u8 *ppp_hdr;
|
|
|
|
if (hdr->flags & GRE_ACK)
|
|
offset += sizeof_field(struct pptp_gre_header, ack);
|
|
|
|
ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
|
|
sizeof(_ppp_hdr),
|
|
data, *p_hlen, _ppp_hdr);
|
|
if (!ppp_hdr)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
switch (PPP_PROTOCOL(ppp_hdr)) {
|
|
case PPP_IP:
|
|
*p_proto = htons(ETH_P_IP);
|
|
break;
|
|
case PPP_IPV6:
|
|
*p_proto = htons(ETH_P_IPV6);
|
|
break;
|
|
default:
|
|
/* Could probably catch some more like MPLS */
|
|
break;
|
|
}
|
|
|
|
offset += PPP_HDRLEN;
|
|
}
|
|
|
|
*p_nhoff += offset;
|
|
key_control->flags |= FLOW_DIS_ENCAPSULATION;
|
|
if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
|
|
return FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
}
|
|
|
|
/**
|
|
* __skb_flow_dissect_batadv() - dissect batman-adv header
|
|
* @skb: sk_buff to with the batman-adv header
|
|
* @key_control: flow dissectors control key
|
|
* @data: raw buffer pointer to the packet, if NULL use skb->data
|
|
* @p_proto: pointer used to update the protocol to process next
|
|
* @p_nhoff: pointer used to update inner network header offset
|
|
* @hlen: packet header length
|
|
* @flags: any combination of FLOW_DISSECTOR_F_*
|
|
*
|
|
* ETH_P_BATMAN packets are tried to be dissected. Only
|
|
* &struct batadv_unicast packets are actually processed because they contain an
|
|
* inner ethernet header and are usually followed by actual network header. This
|
|
* allows the flow dissector to continue processing the packet.
|
|
*
|
|
* Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
|
|
* FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
|
|
* otherwise FLOW_DISSECT_RET_OUT_BAD
|
|
*/
|
|
static enum flow_dissect_ret
|
|
__skb_flow_dissect_batadv(const struct sk_buff *skb,
|
|
struct flow_dissector_key_control *key_control,
|
|
const void *data, __be16 *p_proto, int *p_nhoff,
|
|
int hlen, unsigned int flags)
|
|
{
|
|
struct {
|
|
struct batadv_unicast_packet batadv_unicast;
|
|
struct ethhdr eth;
|
|
} *hdr, _hdr;
|
|
|
|
hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr), data, hlen,
|
|
&_hdr);
|
|
if (!hdr)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
if (hdr->batadv_unicast.version != BATADV_COMPAT_VERSION)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
if (hdr->batadv_unicast.packet_type != BATADV_UNICAST)
|
|
return FLOW_DISSECT_RET_OUT_BAD;
|
|
|
|
*p_proto = hdr->eth.h_proto;
|
|
*p_nhoff += sizeof(*hdr);
|
|
|
|
key_control->flags |= FLOW_DIS_ENCAPSULATION;
|
|
if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
|
|
return FLOW_DISSECT_RET_OUT_GOOD;
|
|
|
|
return FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
}
|
|
|
|
static void
|
|
__skb_flow_dissect_tcp(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const void *data,
|
|
int thoff, int hlen)
|
|
{
|
|
struct flow_dissector_key_tcp *key_tcp;
|
|
struct tcphdr *th, _th;
|
|
|
|
if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_TCP))
|
|
return;
|
|
|
|
th = __skb_header_pointer(skb, thoff, sizeof(_th), data, hlen, &_th);
|
|
if (!th)
|
|
return;
|
|
|
|
if (unlikely(__tcp_hdrlen(th) < sizeof(_th)))
|
|
return;
|
|
|
|
key_tcp = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_TCP,
|
|
target_container);
|
|
key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
|
|
}
|
|
|
|
static void
|
|
__skb_flow_dissect_ports(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const void *data,
|
|
int nhoff, u8 ip_proto, int hlen)
|
|
{
|
|
enum flow_dissector_key_id dissector_ports = FLOW_DISSECTOR_KEY_MAX;
|
|
struct flow_dissector_key_ports *key_ports;
|
|
|
|
if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
|
|
dissector_ports = FLOW_DISSECTOR_KEY_PORTS;
|
|
else if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_PORTS_RANGE))
|
|
dissector_ports = FLOW_DISSECTOR_KEY_PORTS_RANGE;
|
|
|
|
if (dissector_ports == FLOW_DISSECTOR_KEY_MAX)
|
|
return;
|
|
|
|
key_ports = skb_flow_dissector_target(flow_dissector,
|
|
dissector_ports,
|
|
target_container);
|
|
key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
|
|
data, hlen);
|
|
}
|
|
|
|
static void
|
|
__skb_flow_dissect_ipv4(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const void *data,
|
|
const struct iphdr *iph)
|
|
{
|
|
struct flow_dissector_key_ip *key_ip;
|
|
|
|
if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
|
|
return;
|
|
|
|
key_ip = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_IP,
|
|
target_container);
|
|
key_ip->tos = iph->tos;
|
|
key_ip->ttl = iph->ttl;
|
|
}
|
|
|
|
static void
|
|
__skb_flow_dissect_ipv6(const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const void *data,
|
|
const struct ipv6hdr *iph)
|
|
{
|
|
struct flow_dissector_key_ip *key_ip;
|
|
|
|
if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
|
|
return;
|
|
|
|
key_ip = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_IP,
|
|
target_container);
|
|
key_ip->tos = ipv6_get_dsfield(iph);
|
|
key_ip->ttl = iph->hop_limit;
|
|
}
|
|
|
|
/* Maximum number of protocol headers that can be parsed in
|
|
* __skb_flow_dissect
|
|
*/
|
|
#define MAX_FLOW_DISSECT_HDRS 15
|
|
|
|
static bool skb_flow_dissect_allowed(int *num_hdrs)
|
|
{
|
|
++*num_hdrs;
|
|
|
|
return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
|
|
}
|
|
|
|
static void __skb_flow_bpf_to_target(const struct bpf_flow_keys *flow_keys,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container)
|
|
{
|
|
struct flow_dissector_key_ports *key_ports = NULL;
|
|
struct flow_dissector_key_control *key_control;
|
|
struct flow_dissector_key_basic *key_basic;
|
|
struct flow_dissector_key_addrs *key_addrs;
|
|
struct flow_dissector_key_tags *key_tags;
|
|
|
|
key_control = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_CONTROL,
|
|
target_container);
|
|
key_control->thoff = flow_keys->thoff;
|
|
if (flow_keys->is_frag)
|
|
key_control->flags |= FLOW_DIS_IS_FRAGMENT;
|
|
if (flow_keys->is_first_frag)
|
|
key_control->flags |= FLOW_DIS_FIRST_FRAG;
|
|
if (flow_keys->is_encap)
|
|
key_control->flags |= FLOW_DIS_ENCAPSULATION;
|
|
|
|
key_basic = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_BASIC,
|
|
target_container);
|
|
key_basic->n_proto = flow_keys->n_proto;
|
|
key_basic->ip_proto = flow_keys->ip_proto;
|
|
|
|
if (flow_keys->addr_proto == ETH_P_IP &&
|
|
dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
|
|
key_addrs = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_IPV4_ADDRS,
|
|
target_container);
|
|
key_addrs->v4addrs.src = flow_keys->ipv4_src;
|
|
key_addrs->v4addrs.dst = flow_keys->ipv4_dst;
|
|
key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
|
|
} else if (flow_keys->addr_proto == ETH_P_IPV6 &&
|
|
dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
|
|
key_addrs = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_IPV6_ADDRS,
|
|
target_container);
|
|
memcpy(&key_addrs->v6addrs.src, &flow_keys->ipv6_src,
|
|
sizeof(key_addrs->v6addrs.src));
|
|
memcpy(&key_addrs->v6addrs.dst, &flow_keys->ipv6_dst,
|
|
sizeof(key_addrs->v6addrs.dst));
|
|
key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
|
|
key_ports = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_PORTS,
|
|
target_container);
|
|
else if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_PORTS_RANGE))
|
|
key_ports = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_PORTS_RANGE,
|
|
target_container);
|
|
|
|
if (key_ports) {
|
|
key_ports->src = flow_keys->sport;
|
|
key_ports->dst = flow_keys->dport;
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
|
|
key_tags = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_FLOW_LABEL,
|
|
target_container);
|
|
key_tags->flow_label = ntohl(flow_keys->flow_label);
|
|
}
|
|
}
|
|
|
|
u32 bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
|
|
__be16 proto, int nhoff, int hlen, unsigned int flags)
|
|
{
|
|
struct bpf_flow_keys *flow_keys = ctx->flow_keys;
|
|
u32 result;
|
|
|
|
/* Pass parameters to the BPF program */
|
|
memset(flow_keys, 0, sizeof(*flow_keys));
|
|
flow_keys->n_proto = proto;
|
|
flow_keys->nhoff = nhoff;
|
|
flow_keys->thoff = flow_keys->nhoff;
|
|
|
|
BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG !=
|
|
(int)FLOW_DISSECTOR_F_PARSE_1ST_FRAG);
|
|
BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL !=
|
|
(int)FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
|
|
BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP !=
|
|
(int)FLOW_DISSECTOR_F_STOP_AT_ENCAP);
|
|
flow_keys->flags = flags;
|
|
|
|
result = bpf_prog_run_pin_on_cpu(prog, ctx);
|
|
|
|
flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
|
|
flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
|
|
flow_keys->nhoff, hlen);
|
|
|
|
return result;
|
|
}
|
|
|
|
static bool is_pppoe_ses_hdr_valid(const struct pppoe_hdr *hdr)
|
|
{
|
|
return hdr->ver == 1 && hdr->type == 1 && hdr->code == 0;
|
|
}
|
|
|
|
/**
|
|
* __skb_flow_dissect - extract the flow_keys struct and return it
|
|
* @net: associated network namespace, derived from @skb if NULL
|
|
* @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
|
|
* @flow_dissector: list of keys to dissect
|
|
* @target_container: target structure to put dissected values into
|
|
* @data: raw buffer pointer to the packet, if NULL use skb->data
|
|
* @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
|
|
* @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
|
|
* @hlen: packet header length, if @data is NULL use skb_headlen(skb)
|
|
* @flags: flags that control the dissection process, e.g.
|
|
* FLOW_DISSECTOR_F_STOP_AT_ENCAP.
|
|
*
|
|
* The function will try to retrieve individual keys into target specified
|
|
* by flow_dissector from either the skbuff or a raw buffer specified by the
|
|
* rest parameters.
|
|
*
|
|
* Caller must take care of zeroing target container memory.
|
|
*/
|
|
bool __skb_flow_dissect(const struct net *net,
|
|
const struct sk_buff *skb,
|
|
struct flow_dissector *flow_dissector,
|
|
void *target_container, const void *data,
|
|
__be16 proto, int nhoff, int hlen, unsigned int flags)
|
|
{
|
|
struct flow_dissector_key_control *key_control;
|
|
struct flow_dissector_key_basic *key_basic;
|
|
struct flow_dissector_key_addrs *key_addrs;
|
|
struct flow_dissector_key_tags *key_tags;
|
|
struct flow_dissector_key_vlan *key_vlan;
|
|
enum flow_dissect_ret fdret;
|
|
enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
|
|
bool mpls_el = false;
|
|
int mpls_lse = 0;
|
|
int num_hdrs = 0;
|
|
u8 ip_proto = 0;
|
|
bool ret;
|
|
|
|
if (!data) {
|
|
data = skb->data;
|
|
proto = skb_vlan_tag_present(skb) ?
|
|
skb->vlan_proto : skb->protocol;
|
|
nhoff = skb_network_offset(skb);
|
|
hlen = skb_headlen(skb);
|
|
#if IS_ENABLED(CONFIG_NET_DSA)
|
|
if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) &&
|
|
proto == htons(ETH_P_XDSA))) {
|
|
struct metadata_dst *md_dst = skb_metadata_dst(skb);
|
|
const struct dsa_device_ops *ops;
|
|
int offset = 0;
|
|
|
|
ops = skb->dev->dsa_ptr->tag_ops;
|
|
/* Only DSA header taggers break flow dissection */
|
|
if (ops->needed_headroom &&
|
|
(!md_dst || md_dst->type != METADATA_HW_PORT_MUX)) {
|
|
if (ops->flow_dissect)
|
|
ops->flow_dissect(skb, &proto, &offset);
|
|
else
|
|
dsa_tag_generic_flow_dissect(skb,
|
|
&proto,
|
|
&offset);
|
|
hlen -= offset;
|
|
nhoff += offset;
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/* It is ensured by skb_flow_dissector_init() that control key will
|
|
* be always present.
|
|
*/
|
|
key_control = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_CONTROL,
|
|
target_container);
|
|
|
|
/* It is ensured by skb_flow_dissector_init() that basic key will
|
|
* be always present.
|
|
*/
|
|
key_basic = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_BASIC,
|
|
target_container);
|
|
|
|
if (skb) {
|
|
if (!net) {
|
|
if (skb->dev)
|
|
net = dev_net(skb->dev);
|
|
else if (skb->sk)
|
|
net = sock_net(skb->sk);
|
|
}
|
|
}
|
|
|
|
DEBUG_NET_WARN_ON_ONCE(!net);
|
|
if (net) {
|
|
enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
|
|
struct bpf_prog_array *run_array;
|
|
|
|
rcu_read_lock();
|
|
run_array = rcu_dereference(init_net.bpf.run_array[type]);
|
|
if (!run_array)
|
|
run_array = rcu_dereference(net->bpf.run_array[type]);
|
|
|
|
if (run_array) {
|
|
struct bpf_flow_keys flow_keys;
|
|
struct bpf_flow_dissector ctx = {
|
|
.flow_keys = &flow_keys,
|
|
.data = data,
|
|
.data_end = data + hlen,
|
|
};
|
|
__be16 n_proto = proto;
|
|
struct bpf_prog *prog;
|
|
u32 result;
|
|
|
|
if (skb) {
|
|
ctx.skb = skb;
|
|
/* we can't use 'proto' in the skb case
|
|
* because it might be set to skb->vlan_proto
|
|
* which has been pulled from the data
|
|
*/
|
|
n_proto = skb->protocol;
|
|
}
|
|
|
|
prog = READ_ONCE(run_array->items[0].prog);
|
|
result = bpf_flow_dissect(prog, &ctx, n_proto, nhoff,
|
|
hlen, flags);
|
|
if (result == BPF_FLOW_DISSECTOR_CONTINUE)
|
|
goto dissect_continue;
|
|
__skb_flow_bpf_to_target(&flow_keys, flow_dissector,
|
|
target_container);
|
|
rcu_read_unlock();
|
|
return result == BPF_OK;
|
|
}
|
|
dissect_continue:
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
|
|
struct ethhdr *eth = eth_hdr(skb);
|
|
struct flow_dissector_key_eth_addrs *key_eth_addrs;
|
|
|
|
key_eth_addrs = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_ETH_ADDRS,
|
|
target_container);
|
|
memcpy(key_eth_addrs, eth, sizeof(*key_eth_addrs));
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_NUM_OF_VLANS)) {
|
|
struct flow_dissector_key_num_of_vlans *key_num_of_vlans;
|
|
|
|
key_num_of_vlans = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
|
|
target_container);
|
|
key_num_of_vlans->num_of_vlans = 0;
|
|
}
|
|
|
|
proto_again:
|
|
fdret = FLOW_DISSECT_RET_CONTINUE;
|
|
|
|
switch (proto) {
|
|
case htons(ETH_P_IP): {
|
|
const struct iphdr *iph;
|
|
struct iphdr _iph;
|
|
|
|
iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
|
|
if (!iph || iph->ihl < 5) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
nhoff += iph->ihl * 4;
|
|
|
|
ip_proto = iph->protocol;
|
|
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
|
|
key_addrs = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_IPV4_ADDRS,
|
|
target_container);
|
|
|
|
memcpy(&key_addrs->v4addrs.src, &iph->saddr,
|
|
sizeof(key_addrs->v4addrs.src));
|
|
memcpy(&key_addrs->v4addrs.dst, &iph->daddr,
|
|
sizeof(key_addrs->v4addrs.dst));
|
|
key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
|
|
}
|
|
|
|
__skb_flow_dissect_ipv4(skb, flow_dissector,
|
|
target_container, data, iph);
|
|
|
|
if (ip_is_fragment(iph)) {
|
|
key_control->flags |= FLOW_DIS_IS_FRAGMENT;
|
|
|
|
if (iph->frag_off & htons(IP_OFFSET)) {
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
} else {
|
|
key_control->flags |= FLOW_DIS_FIRST_FRAG;
|
|
if (!(flags &
|
|
FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
break;
|
|
}
|
|
case htons(ETH_P_IPV6): {
|
|
const struct ipv6hdr *iph;
|
|
struct ipv6hdr _iph;
|
|
|
|
iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
|
|
if (!iph) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
ip_proto = iph->nexthdr;
|
|
nhoff += sizeof(struct ipv6hdr);
|
|
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
|
|
key_addrs = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_IPV6_ADDRS,
|
|
target_container);
|
|
|
|
memcpy(&key_addrs->v6addrs.src, &iph->saddr,
|
|
sizeof(key_addrs->v6addrs.src));
|
|
memcpy(&key_addrs->v6addrs.dst, &iph->daddr,
|
|
sizeof(key_addrs->v6addrs.dst));
|
|
key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
|
|
}
|
|
|
|
if ((dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
|
|
(flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
|
|
ip6_flowlabel(iph)) {
|
|
__be32 flow_label = ip6_flowlabel(iph);
|
|
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
|
|
key_tags = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_FLOW_LABEL,
|
|
target_container);
|
|
key_tags->flow_label = ntohl(flow_label);
|
|
}
|
|
if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
}
|
|
|
|
__skb_flow_dissect_ipv6(skb, flow_dissector,
|
|
target_container, data, iph);
|
|
|
|
break;
|
|
}
|
|
case htons(ETH_P_8021AD):
|
|
case htons(ETH_P_8021Q): {
|
|
const struct vlan_hdr *vlan = NULL;
|
|
struct vlan_hdr _vlan;
|
|
__be16 saved_vlan_tpid = proto;
|
|
|
|
if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX &&
|
|
skb && skb_vlan_tag_present(skb)) {
|
|
proto = skb->protocol;
|
|
} else {
|
|
vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
|
|
data, hlen, &_vlan);
|
|
if (!vlan) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
proto = vlan->h_vlan_encapsulated_proto;
|
|
nhoff += sizeof(*vlan);
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_NUM_OF_VLANS) &&
|
|
!(key_control->flags & FLOW_DIS_ENCAPSULATION)) {
|
|
struct flow_dissector_key_num_of_vlans *key_nvs;
|
|
|
|
key_nvs = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
|
|
target_container);
|
|
key_nvs->num_of_vlans++;
|
|
}
|
|
|
|
if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
|
|
dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
|
|
} else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {
|
|
dissector_vlan = FLOW_DISSECTOR_KEY_CVLAN;
|
|
} else {
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
break;
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector, dissector_vlan)) {
|
|
key_vlan = skb_flow_dissector_target(flow_dissector,
|
|
dissector_vlan,
|
|
target_container);
|
|
|
|
if (!vlan) {
|
|
key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
|
|
key_vlan->vlan_priority = skb_vlan_tag_get_prio(skb);
|
|
} else {
|
|
key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
|
|
VLAN_VID_MASK;
|
|
key_vlan->vlan_priority =
|
|
(ntohs(vlan->h_vlan_TCI) &
|
|
VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
|
|
}
|
|
key_vlan->vlan_tpid = saved_vlan_tpid;
|
|
key_vlan->vlan_eth_type = proto;
|
|
}
|
|
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
break;
|
|
}
|
|
case htons(ETH_P_PPP_SES): {
|
|
struct {
|
|
struct pppoe_hdr hdr;
|
|
__be16 proto;
|
|
} *hdr, _hdr;
|
|
u16 ppp_proto;
|
|
|
|
hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
|
|
if (!hdr) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
if (!is_pppoe_ses_hdr_valid(&hdr->hdr)) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
/* least significant bit of the most significant octet
|
|
* indicates if protocol field was compressed
|
|
*/
|
|
ppp_proto = ntohs(hdr->proto);
|
|
if (ppp_proto & 0x0100) {
|
|
ppp_proto = ppp_proto >> 8;
|
|
nhoff += PPPOE_SES_HLEN - 1;
|
|
} else {
|
|
nhoff += PPPOE_SES_HLEN;
|
|
}
|
|
|
|
if (ppp_proto == PPP_IP) {
|
|
proto = htons(ETH_P_IP);
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
} else if (ppp_proto == PPP_IPV6) {
|
|
proto = htons(ETH_P_IPV6);
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
} else if (ppp_proto == PPP_MPLS_UC) {
|
|
proto = htons(ETH_P_MPLS_UC);
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
} else if (ppp_proto == PPP_MPLS_MC) {
|
|
proto = htons(ETH_P_MPLS_MC);
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
} else if (ppp_proto_is_valid(ppp_proto)) {
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
} else {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_PPPOE)) {
|
|
struct flow_dissector_key_pppoe *key_pppoe;
|
|
|
|
key_pppoe = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_PPPOE,
|
|
target_container);
|
|
key_pppoe->session_id = hdr->hdr.sid;
|
|
key_pppoe->ppp_proto = htons(ppp_proto);
|
|
key_pppoe->type = htons(ETH_P_PPP_SES);
|
|
}
|
|
break;
|
|
}
|
|
case htons(ETH_P_TIPC): {
|
|
struct tipc_basic_hdr *hdr, _hdr;
|
|
|
|
hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
|
|
data, hlen, &_hdr);
|
|
if (!hdr) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
if (dissector_uses_key(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_TIPC)) {
|
|
key_addrs = skb_flow_dissector_target(flow_dissector,
|
|
FLOW_DISSECTOR_KEY_TIPC,
|
|
target_container);
|
|
key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
|
|
key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
|
|
}
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
|
|
case htons(ETH_P_MPLS_UC):
|
|
case htons(ETH_P_MPLS_MC):
|
|
fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
|
|
target_container, data,
|
|
nhoff, hlen, mpls_lse,
|
|
&mpls_el);
|
|
nhoff += sizeof(struct mpls_label);
|
|
mpls_lse++;
|
|
break;
|
|
case htons(ETH_P_FCOE):
|
|
if ((hlen - nhoff) < FCOE_HEADER_LEN) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
nhoff += FCOE_HEADER_LEN;
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
|
|
case htons(ETH_P_ARP):
|
|
case htons(ETH_P_RARP):
|
|
fdret = __skb_flow_dissect_arp(skb, flow_dissector,
|
|
target_container, data,
|
|
nhoff, hlen);
|
|
break;
|
|
|
|
case htons(ETH_P_BATMAN):
|
|
fdret = __skb_flow_dissect_batadv(skb, key_control, data,
|
|
&proto, &nhoff, hlen, flags);
|
|
break;
|
|
|
|
case htons(ETH_P_1588): {
|
|
struct ptp_header *hdr, _hdr;
|
|
|
|
hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
|
|
hlen, &_hdr);
|
|
if (!hdr) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
nhoff += sizeof(struct ptp_header);
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
|
|
case htons(ETH_P_PRP):
|
|
case htons(ETH_P_HSR): {
|
|
struct hsr_tag *hdr, _hdr;
|
|
|
|
hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen,
|
|
&_hdr);
|
|
if (!hdr) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
proto = hdr->encap_proto;
|
|
nhoff += HSR_HLEN;
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
break;
|
|
}
|
|
|
|
case htons(ETH_P_CFM):
|
|
fdret = __skb_flow_dissect_cfm(skb, flow_dissector,
|
|
target_container, data,
|
|
nhoff, hlen);
|
|
break;
|
|
|
|
default:
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
/* Process result of proto processing */
|
|
switch (fdret) {
|
|
case FLOW_DISSECT_RET_OUT_GOOD:
|
|
goto out_good;
|
|
case FLOW_DISSECT_RET_PROTO_AGAIN:
|
|
if (skb_flow_dissect_allowed(&num_hdrs))
|
|
goto proto_again;
|
|
goto out_good;
|
|
case FLOW_DISSECT_RET_CONTINUE:
|
|
case FLOW_DISSECT_RET_IPPROTO_AGAIN:
|
|
break;
|
|
case FLOW_DISSECT_RET_OUT_BAD:
|
|
default:
|
|
goto out_bad;
|
|
}
|
|
|
|
ip_proto_again:
|
|
fdret = FLOW_DISSECT_RET_CONTINUE;
|
|
|
|
switch (ip_proto) {
|
|
case IPPROTO_GRE:
|
|
if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
|
|
fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
|
|
target_container, data,
|
|
&proto, &nhoff, &hlen, flags);
|
|
break;
|
|
|
|
case NEXTHDR_HOP:
|
|
case NEXTHDR_ROUTING:
|
|
case NEXTHDR_DEST: {
|
|
u8 _opthdr[2], *opthdr;
|
|
|
|
if (proto != htons(ETH_P_IPV6))
|
|
break;
|
|
|
|
opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
|
|
data, hlen, &_opthdr);
|
|
if (!opthdr) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
ip_proto = opthdr[0];
|
|
nhoff += (opthdr[1] + 1) << 3;
|
|
|
|
fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
|
|
break;
|
|
}
|
|
case NEXTHDR_FRAGMENT: {
|
|
struct frag_hdr _fh, *fh;
|
|
|
|
if (proto != htons(ETH_P_IPV6))
|
|
break;
|
|
|
|
fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
|
|
data, hlen, &_fh);
|
|
|
|
if (!fh) {
|
|
fdret = FLOW_DISSECT_RET_OUT_BAD;
|
|
break;
|
|
}
|
|
|
|
key_control->flags |= FLOW_DIS_IS_FRAGMENT;
|
|
|
|
nhoff += sizeof(_fh);
|
|
ip_proto = fh->nexthdr;
|
|
|
|
if (!(fh->frag_off & htons(IP6_OFFSET))) {
|
|
key_control->flags |= FLOW_DIS_FIRST_FRAG;
|
|
if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
|
|
fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
|
|
break;
|
|
}
|
|
}
|
|
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
case IPPROTO_IPIP:
|
|
if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
|
|
proto = htons(ETH_P_IP);
|
|
|
|
key_control->flags |= FLOW_DIS_ENCAPSULATION;
|
|
if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
break;
|
|
|
|
case IPPROTO_IPV6:
|
|
if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
|
|
proto = htons(ETH_P_IPV6);
|
|
|
|
key_control->flags |= FLOW_DIS_ENCAPSULATION;
|
|
if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
|
|
fdret = FLOW_DISSECT_RET_OUT_GOOD;
|
|
break;
|
|
}
|
|
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
break;
|
|
|
|
|
|
case IPPROTO_MPLS:
|
|
proto = htons(ETH_P_MPLS_UC);
|
|
fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
|
|
break;
|
|
|
|
case IPPROTO_TCP:
|
|
__skb_flow_dissect_tcp(skb, flow_dissector, target_container,
|
|
data, nhoff, hlen);
|
|
break;
|
|
|
|
case IPPROTO_ICMP:
|
|
case IPPROTO_ICMPV6:
|
|
__skb_flow_dissect_icmp(skb, flow_dissector, target_container,
|
|
data, nhoff, hlen);
|
|
break;
|
|
case IPPROTO_L2TP:
|
|
__skb_flow_dissect_l2tpv3(skb, flow_dissector, target_container,
|
|
data, nhoff, hlen);
|
|
break;
|
|
case IPPROTO_ESP:
|
|
__skb_flow_dissect_esp(skb, flow_dissector, target_container,
|
|
data, nhoff, hlen);
|
|
break;
|
|
case IPPROTO_AH:
|
|
__skb_flow_dissect_ah(skb, flow_dissector, target_container,
|
|
data, nhoff, hlen);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
if (!(key_control->flags & FLOW_DIS_IS_FRAGMENT))
|
|
__skb_flow_dissect_ports(skb, flow_dissector, target_container,
|
|
data, nhoff, ip_proto, hlen);
|
|
|
|
/* Process result of IP proto processing */
|
|
switch (fdret) {
|
|
case FLOW_DISSECT_RET_PROTO_AGAIN:
|
|
if (skb_flow_dissect_allowed(&num_hdrs))
|
|
goto proto_again;
|
|
break;
|
|
case FLOW_DISSECT_RET_IPPROTO_AGAIN:
|
|
if (skb_flow_dissect_allowed(&num_hdrs))
|
|
goto ip_proto_again;
|
|
break;
|
|
case FLOW_DISSECT_RET_OUT_GOOD:
|
|
case FLOW_DISSECT_RET_CONTINUE:
|
|
break;
|
|
case FLOW_DISSECT_RET_OUT_BAD:
|
|
default:
|
|
goto out_bad;
|
|
}
|
|
|
|
out_good:
|
|
ret = true;
|
|
|
|
out:
|
|
key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
|
|
key_basic->n_proto = proto;
|
|
key_basic->ip_proto = ip_proto;
|
|
|
|
return ret;
|
|
|
|
out_bad:
|
|
ret = false;
|
|
goto out;
|
|
}
|
|
EXPORT_SYMBOL(__skb_flow_dissect);
|
|
|
|
static siphash_aligned_key_t hashrnd;
|
|
static __always_inline void __flow_hash_secret_init(void)
|
|
{
|
|
net_get_random_once(&hashrnd, sizeof(hashrnd));
|
|
}
|
|
|
|
static const void *flow_keys_hash_start(const struct flow_keys *flow)
|
|
{
|
|
BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % SIPHASH_ALIGNMENT);
|
|
return &flow->FLOW_KEYS_HASH_START_FIELD;
|
|
}
|
|
|
|
static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
|
|
{
|
|
size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
|
|
|
|
BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
|
|
|
|
switch (flow->control.addr_type) {
|
|
case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
|
|
diff -= sizeof(flow->addrs.v4addrs);
|
|
break;
|
|
case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
|
|
diff -= sizeof(flow->addrs.v6addrs);
|
|
break;
|
|
case FLOW_DISSECTOR_KEY_TIPC:
|
|
diff -= sizeof(flow->addrs.tipckey);
|
|
break;
|
|
}
|
|
return sizeof(*flow) - diff;
|
|
}
|
|
|
|
__be32 flow_get_u32_src(const struct flow_keys *flow)
|
|
{
|
|
switch (flow->control.addr_type) {
|
|
case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
|
|
return flow->addrs.v4addrs.src;
|
|
case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
|
|
return (__force __be32)ipv6_addr_hash(
|
|
&flow->addrs.v6addrs.src);
|
|
case FLOW_DISSECTOR_KEY_TIPC:
|
|
return flow->addrs.tipckey.key;
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(flow_get_u32_src);
|
|
|
|
__be32 flow_get_u32_dst(const struct flow_keys *flow)
|
|
{
|
|
switch (flow->control.addr_type) {
|
|
case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
|
|
return flow->addrs.v4addrs.dst;
|
|
case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
|
|
return (__force __be32)ipv6_addr_hash(
|
|
&flow->addrs.v6addrs.dst);
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(flow_get_u32_dst);
|
|
|
|
/* Sort the source and destination IP and the ports,
|
|
* to have consistent hash within the two directions
|
|
*/
|
|
static inline void __flow_hash_consistentify(struct flow_keys *keys)
|
|
{
|
|
int addr_diff, i;
|
|
|
|
switch (keys->control.addr_type) {
|
|
case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
|
|
if ((__force u32)keys->addrs.v4addrs.dst <
|
|
(__force u32)keys->addrs.v4addrs.src)
|
|
swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
|
|
|
|
if ((__force u16)keys->ports.dst <
|
|
(__force u16)keys->ports.src) {
|
|
swap(keys->ports.src, keys->ports.dst);
|
|
}
|
|
break;
|
|
case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
|
|
addr_diff = memcmp(&keys->addrs.v6addrs.dst,
|
|
&keys->addrs.v6addrs.src,
|
|
sizeof(keys->addrs.v6addrs.dst));
|
|
if (addr_diff < 0) {
|
|
for (i = 0; i < 4; i++)
|
|
swap(keys->addrs.v6addrs.src.s6_addr32[i],
|
|
keys->addrs.v6addrs.dst.s6_addr32[i]);
|
|
}
|
|
if ((__force u16)keys->ports.dst <
|
|
(__force u16)keys->ports.src) {
|
|
swap(keys->ports.src, keys->ports.dst);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
static inline u32 __flow_hash_from_keys(struct flow_keys *keys,
|
|
const siphash_key_t *keyval)
|
|
{
|
|
u32 hash;
|
|
|
|
__flow_hash_consistentify(keys);
|
|
|
|
hash = siphash(flow_keys_hash_start(keys),
|
|
flow_keys_hash_length(keys), keyval);
|
|
if (!hash)
|
|
hash = 1;
|
|
|
|
return hash;
|
|
}
|
|
|
|
u32 flow_hash_from_keys(struct flow_keys *keys)
|
|
{
|
|
__flow_hash_secret_init();
|
|
return __flow_hash_from_keys(keys, &hashrnd);
|
|
}
|
|
EXPORT_SYMBOL(flow_hash_from_keys);
|
|
|
|
u32 flow_hash_from_keys_seed(struct flow_keys *keys,
|
|
const siphash_key_t *keyval)
|
|
{
|
|
return __flow_hash_from_keys(keys, keyval);
|
|
}
|
|
EXPORT_SYMBOL(flow_hash_from_keys_seed);
|
|
|
|
static inline u32 ___skb_get_hash(const struct sk_buff *skb,
|
|
struct flow_keys *keys,
|
|
const siphash_key_t *keyval)
|
|
{
|
|
skb_flow_dissect_flow_keys(skb, keys,
|
|
FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
|
|
|
|
return __flow_hash_from_keys(keys, keyval);
|
|
}
|
|
|
|
struct _flow_keys_digest_data {
|
|
__be16 n_proto;
|
|
u8 ip_proto;
|
|
u8 padding;
|
|
__be32 ports;
|
|
__be32 src;
|
|
__be32 dst;
|
|
};
|
|
|
|
void make_flow_keys_digest(struct flow_keys_digest *digest,
|
|
const struct flow_keys *flow)
|
|
{
|
|
struct _flow_keys_digest_data *data =
|
|
(struct _flow_keys_digest_data *)digest;
|
|
|
|
BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
|
|
|
|
memset(digest, 0, sizeof(*digest));
|
|
|
|
data->n_proto = flow->basic.n_proto;
|
|
data->ip_proto = flow->basic.ip_proto;
|
|
data->ports = flow->ports.ports;
|
|
data->src = flow->addrs.v4addrs.src;
|
|
data->dst = flow->addrs.v4addrs.dst;
|
|
}
|
|
EXPORT_SYMBOL(make_flow_keys_digest);
|
|
|
|
static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
|
|
|
|
u32 __skb_get_hash_symmetric_net(const struct net *net, const struct sk_buff *skb)
|
|
{
|
|
struct flow_keys keys;
|
|
|
|
__flow_hash_secret_init();
|
|
|
|
memset(&keys, 0, sizeof(keys));
|
|
__skb_flow_dissect(net, skb, &flow_keys_dissector_symmetric,
|
|
&keys, NULL, 0, 0, 0, 0);
|
|
|
|
return __flow_hash_from_keys(&keys, &hashrnd);
|
|
}
|
|
EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric_net);
|
|
|
|
/**
|
|
* __skb_get_hash_net: calculate a flow hash
|
|
* @net: associated network namespace, derived from @skb if NULL
|
|
* @skb: sk_buff to calculate flow hash from
|
|
*
|
|
* This function calculates a flow hash based on src/dst addresses
|
|
* and src/dst port numbers. Sets hash in skb to non-zero hash value
|
|
* on success, zero indicates no valid hash. Also, sets l4_hash in skb
|
|
* if hash is a canonical 4-tuple hash over transport ports.
|
|
*/
|
|
void __skb_get_hash_net(const struct net *net, struct sk_buff *skb)
|
|
{
|
|
struct flow_keys keys;
|
|
u32 hash;
|
|
|
|
memset(&keys, 0, sizeof(keys));
|
|
|
|
__skb_flow_dissect(net, skb, &flow_keys_dissector,
|
|
&keys, NULL, 0, 0, 0,
|
|
FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
|
|
|
|
__flow_hash_secret_init();
|
|
|
|
hash = __flow_hash_from_keys(&keys, &hashrnd);
|
|
|
|
__skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
|
|
}
|
|
EXPORT_SYMBOL(__skb_get_hash_net);
|
|
|
|
__u32 skb_get_hash_perturb(const struct sk_buff *skb,
|
|
const siphash_key_t *perturb)
|
|
{
|
|
struct flow_keys keys;
|
|
|
|
return ___skb_get_hash(skb, &keys, perturb);
|
|
}
|
|
EXPORT_SYMBOL(skb_get_hash_perturb);
|
|
|
|
u32 __skb_get_poff(const struct sk_buff *skb, const void *data,
|
|
const struct flow_keys_basic *keys, int hlen)
|
|
{
|
|
u32 poff = keys->control.thoff;
|
|
|
|
/* skip L4 headers for fragments after the first */
|
|
if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
|
|
!(keys->control.flags & FLOW_DIS_FIRST_FRAG))
|
|
return poff;
|
|
|
|
switch (keys->basic.ip_proto) {
|
|
case IPPROTO_TCP: {
|
|
/* access doff as u8 to avoid unaligned access */
|
|
const u8 *doff;
|
|
u8 _doff;
|
|
|
|
doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
|
|
data, hlen, &_doff);
|
|
if (!doff)
|
|
return poff;
|
|
|
|
poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
|
|
break;
|
|
}
|
|
case IPPROTO_UDP:
|
|
case IPPROTO_UDPLITE:
|
|
poff += sizeof(struct udphdr);
|
|
break;
|
|
/* For the rest, we do not really care about header
|
|
* extensions at this point for now.
|
|
*/
|
|
case IPPROTO_ICMP:
|
|
poff += sizeof(struct icmphdr);
|
|
break;
|
|
case IPPROTO_ICMPV6:
|
|
poff += sizeof(struct icmp6hdr);
|
|
break;
|
|
case IPPROTO_IGMP:
|
|
poff += sizeof(struct igmphdr);
|
|
break;
|
|
case IPPROTO_DCCP:
|
|
poff += sizeof(struct dccp_hdr);
|
|
break;
|
|
case IPPROTO_SCTP:
|
|
poff += sizeof(struct sctphdr);
|
|
break;
|
|
}
|
|
|
|
return poff;
|
|
}
|
|
|
|
/**
|
|
* skb_get_poff - get the offset to the payload
|
|
* @skb: sk_buff to get the payload offset from
|
|
*
|
|
* The function will get the offset to the payload as far as it could
|
|
* be dissected. The main user is currently BPF, so that we can dynamically
|
|
* truncate packets without needing to push actual payload to the user
|
|
* space and can analyze headers only, instead.
|
|
*/
|
|
u32 skb_get_poff(const struct sk_buff *skb)
|
|
{
|
|
struct flow_keys_basic keys;
|
|
|
|
if (!skb_flow_dissect_flow_keys_basic(NULL, skb, &keys,
|
|
NULL, 0, 0, 0, 0))
|
|
return 0;
|
|
|
|
return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
|
|
}
|
|
|
|
__u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
|
|
{
|
|
memset(keys, 0, sizeof(*keys));
|
|
|
|
memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
|
|
sizeof(keys->addrs.v6addrs.src));
|
|
memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
|
|
sizeof(keys->addrs.v6addrs.dst));
|
|
keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
|
|
keys->ports.src = fl6->fl6_sport;
|
|
keys->ports.dst = fl6->fl6_dport;
|
|
keys->keyid.keyid = fl6->fl6_gre_key;
|
|
keys->tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
|
|
keys->basic.ip_proto = fl6->flowi6_proto;
|
|
|
|
return flow_hash_from_keys(keys);
|
|
}
|
|
EXPORT_SYMBOL(__get_hash_from_flowi6);
|
|
|
|
static const struct flow_dissector_key flow_keys_dissector_keys[] = {
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_CONTROL,
|
|
.offset = offsetof(struct flow_keys, control),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_BASIC,
|
|
.offset = offsetof(struct flow_keys, basic),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
|
|
.offset = offsetof(struct flow_keys, addrs.v4addrs),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
|
|
.offset = offsetof(struct flow_keys, addrs.v6addrs),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_TIPC,
|
|
.offset = offsetof(struct flow_keys, addrs.tipckey),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_PORTS,
|
|
.offset = offsetof(struct flow_keys, ports),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_VLAN,
|
|
.offset = offsetof(struct flow_keys, vlan),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
|
|
.offset = offsetof(struct flow_keys, tags),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
|
|
.offset = offsetof(struct flow_keys, keyid),
|
|
},
|
|
};
|
|
|
|
static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_CONTROL,
|
|
.offset = offsetof(struct flow_keys, control),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_BASIC,
|
|
.offset = offsetof(struct flow_keys, basic),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
|
|
.offset = offsetof(struct flow_keys, addrs.v4addrs),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
|
|
.offset = offsetof(struct flow_keys, addrs.v6addrs),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_PORTS,
|
|
.offset = offsetof(struct flow_keys, ports),
|
|
},
|
|
};
|
|
|
|
static const struct flow_dissector_key flow_keys_basic_dissector_keys[] = {
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_CONTROL,
|
|
.offset = offsetof(struct flow_keys, control),
|
|
},
|
|
{
|
|
.key_id = FLOW_DISSECTOR_KEY_BASIC,
|
|
.offset = offsetof(struct flow_keys, basic),
|
|
},
|
|
};
|
|
|
|
struct flow_dissector flow_keys_dissector __read_mostly;
|
|
EXPORT_SYMBOL(flow_keys_dissector);
|
|
|
|
struct flow_dissector flow_keys_basic_dissector __read_mostly;
|
|
EXPORT_SYMBOL(flow_keys_basic_dissector);
|
|
|
|
static int __init init_default_flow_dissectors(void)
|
|
{
|
|
skb_flow_dissector_init(&flow_keys_dissector,
|
|
flow_keys_dissector_keys,
|
|
ARRAY_SIZE(flow_keys_dissector_keys));
|
|
skb_flow_dissector_init(&flow_keys_dissector_symmetric,
|
|
flow_keys_dissector_symmetric_keys,
|
|
ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
|
|
skb_flow_dissector_init(&flow_keys_basic_dissector,
|
|
flow_keys_basic_dissector_keys,
|
|
ARRAY_SIZE(flow_keys_basic_dissector_keys));
|
|
return 0;
|
|
}
|
|
core_initcall(init_default_flow_dissectors);
|