Transports over UDP is intended to encapsulate TCP and other transport protocols directly and securely in UDP.
The goal of this work is twofold: 1) Allow applications to run their own transport layer stack (i.e.from userspace). This eliminates dependencies on the OS (e.g. solves a major dependency issue for Facebook on clients). 2) Make transport layer headers (all of L4) invisible to the network so that they can't do intrusive actions at L4. This will be enforced with DTLS in use. Note that #1 is really about running a transport stack in userspace applications in clients, not necessarily servers. For servers we intend to modified the kernel stack in order to leverage existing implementation for building scalable serves (hence these patches). This is described in more detail in the Internet Draft: https://tools.ietf.org/html/draft-herbert-transports-over-udp-00 In Part I we implement a straightforward encapsulation of TCP in GUE. The implements the basic mechanics of TOU encapsulation for TCP, however does not yet implement the IP addressing interactions so therefore so this is not robust to use in the presence of NAT. TOU is enabled per socket with a new socket option. This implementation includes GSO, GRO, and RCO support. These patches also establish the baseline performance of TOU and isolate the performance cost of UDP encapsulation. Performance results are below. Tested: Various cases of TOU with IPv4, IPv6 using TCP_STREAM and TCP_RR. Also, tested IPIP for comparing TOU encapsulation to IP tunneling. - IPv6 native 1 TCP_STREAM 8394 tps 200 TCP_RR 1726825 tps 100/177/361 90/95/99% latencies - IPv6 TOU with RCO 1 TCP_STREAM 7410 tps 200 TCP_RR 1445603 tps 121/211/395 90/95/99% latencies - IPv4 native 1 TCP_STREAM 8525 tps 200 TCP_RR 1826729 tps 94/166/345 90/95/99% latencies - IPv4 TOU with RCO 1 TCP_STREAM 7624 tps 200 TCP_RR 1599642 tps 108/190/377 90/95/99% latencies - IPIP with GUE and RCO 1 TCP_STREAM 5092 tps 200 TCP_RR 1276716 tps 137/237/445 90/95/99% latencies Tom Herbert (8): net: Change SKB_GSO_DODGY to be a tx_flag fou: Change ip_tunnel_encap to take net argument tou: Base infrastructure for Transport over UDP ipv4: Support TOU tcp: Support for TOU ipv6: Support TOU tcp6: Support for TOU tou: Support for GSO drivers/net/xen-netfront.c | 2 +- include/linux/netdev_features.h | 4 +- include/linux/netdevice.h | 2 +- include/linux/skbuff.h | 6 +- include/linux/virtio_net.h | 2 +- include/net/fou.h | 4 +- include/net/inet_sock.h | 2 + include/net/ip6_tunnel.h | 5 +- include/net/ip_tunnels.h | 6 +- include/net/udp.h | 2 + include/uapi/linux/if_tunnel.h | 10 +++ include/uapi/linux/in.h | 1 + include/uapi/linux/in6.h | 1 + net/core/dev.c | 2 +- net/core/skbuff.c | 2 +- net/ipv4/Makefile | 3 +- net/ipv4/af_inet.c | 4 + net/ipv4/fou.c | 20 ++--- net/ipv4/ip_output.c | 44 +++++++++-- net/ipv4/ip_sockglue.c | 7 ++ net/ipv4/tcp_ipv4.c | 9 ++- net/ipv4/tou.c | 140 +++++++++++++++++++++++++++++++++ net/ipv4/udp_offload.c | 163 +++++++++++++++++++++++++++++++++++++-- net/ipv6/fou6.c | 8 +- net/ipv6/inet6_connection_sock.c | 61 +++++++++++++-- net/ipv6/ipv6_sockglue.c | 7 ++ net/ipv6/tcp_ipv6.c | 11 +-- net/ipv6/udp_offload.c | 128 +++++++++++++++--------------- net/packet/af_packet.c | 2 +- 29 files changed, 538 insertions(+), 120 deletions(-) create mode 100644 net/ipv4/tou.c -- 2.8.0.rc2
