---

monitor.c

// Copyright (c) PLUMgrid, Inc. // Licensed under the Apache License, Version 2.0 (the "License") #include <bcc/proto.h> struct ipkey { u32 inner_sip; u32 inner_dip; u32 outer_sip; u32 outer_dip; u32 vni; }; struct counters { u64 tx_pkts; u64 rx_pkts; u64 tx_bytes; u64 rx_bytes; }; BPF_HASH(stats, struct ipkey, struct counters, 1024); BPF_PROG_ARRAY(parser, 10); enum cb_index { CB_FLAGS = 0, CB_SIP, CB_DIP, CB_VNI, CB_OFFSET, }; // helper func to swap two memory locations static inline void swap32(u32 *a, u32 *b) { u32 t = *a; *a = *b; *b = t; } // helper to swap the fields in an ipkey to give consistent ordering static inline void swap_ipkey(struct ipkey *key) { swap32(&key->outer_sip, &key->outer_dip); swap32(&key->inner_sip, &key->inner_dip); } #define IS_INGRESS 0x1 // initial handler for each packet on an ingress tc filter int handle_ingress(struct __sk_buff *skb) { skb->cb[CB_FLAGS] = IS_INGRESS; parser.call(skb, 1); // jump to generic packet parser return 1; } // initial handler for each packet on an egress tc filter int handle_egress(struct __sk_buff *skb) { skb->cb[CB_FLAGS] = 0; parser.call(skb, 1); // jump to generic packet parser return 1; } // parse the outer vxlan frame int handle_outer(struct __sk_buff *skb) { u8 *cursor = 0; struct ethernet_t *ethernet = cursor_advance(cursor, sizeof(*ethernet)); // filter bcast/mcast from the stats if (ethernet->dst & (1ull << 40)) goto finish; switch (ethernet->type) { case 0x0800: goto ip; default: goto finish; } ip: ; struct ip_t *ip = cursor_advance(cursor, sizeof(*ip)); skb->cb[CB_SIP] = ip->src; skb->cb[CB_DIP] = ip->dst; switch (ip->nextp) { case 17: goto udp; default: goto finish; } udp: ; struct udp_t *udp = cursor_advance(cursor, sizeof(*udp)); switch (udp->dport) { case 4789: goto vxlan; default: goto finish; } vxlan: ; struct vxlan_t *vxlan = cursor_advance(cursor, sizeof(*vxlan)); skb->cb[CB_VNI] = vxlan->key; skb->cb[CB_OFFSET] = (u64)vxlan + sizeof(*vxlan); parser.call(skb, 2); finish: return 1; } // Parse the inner frame, whatever it may be. If it is ipv4, add the inner // source/dest ip to the key, for finer grained stats int handle_inner(struct __sk_buff *skb) { int is_ingress = skb->cb[CB_FLAGS] & IS_INGRESS; struct ipkey key = { .vni=skb->cb[CB_VNI], .outer_sip = skb->cb[CB_SIP], .outer_dip = skb->cb[CB_DIP] }; u8 *cursor = (u8 *)(u64)skb->cb[CB_OFFSET]; struct ethernet_t *ethernet = cursor_advance(cursor, sizeof(*ethernet)); switch (ethernet->type) { case 0x0800: goto ip; default: goto finish; } ip: ; struct ip_t *ip = cursor_advance(cursor, sizeof(*ip)); key.inner_sip = ip->src; key.inner_dip = ip->dst; finish: // consistent ordering if (key.outer_dip < key.outer_sip) swap_ipkey(&key); struct counters zleaf = {0}; struct counters *leaf = stats.lookup_or_try_init(&key, &zleaf); if (leaf) { if (is_ingress) { lock_xadd(&leaf->rx_pkts, 1); lock_xadd(&leaf->rx_bytes, skb->len); } else { lock_xadd(&leaf->tx_pkts, 1); lock_xadd(&leaf->tx_bytes, skb->len); } } return 1; }

---

docroot: /var/www/469ed2f6-4d4b-4a8a-9f5e-ee4ef04d3bc8/public_html

---

curdir: /usr/share/doc/bpfcc-tools/examples/networking/tunnel_monitor

	.		4096
	..		4096
X	README.md		2611
X	chord.png		66306
X	main.py		3412
X	monitor.c		3221
X	monitor.py		2892
X	setup.sh		716
X	simulation.py		5257
X	traffic.sh		1306
X	vxlan.jpg		188797