From c411ed854584a71b0e86ac3019b60e4789d88086 Mon Sep 17 00:00:00 2001 From: Jiri Benc Date: Mon, 28 Aug 2017 21:43:24 +0200 Subject: [PATCH] nsh: add GSO support Add a new nsh/ directory. It currently holds only GSO functions but more will come: in particular, code shared by openvswitch and tc to manipulate NSH headers. For now, assume there's no hardware support for NSH segmentation. We can always introduce netdev->nsh_features later. Signed-off-by: Jiri Benc Signed-off-by: David S. Miller --- net/Kconfig | 1 + net/Makefile | 1 + net/nsh/Kconfig | 9 +++++ net/nsh/Makefile | 1 + net/nsh/nsh.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 103 insertions(+) create mode 100644 net/nsh/Kconfig create mode 100644 net/nsh/Makefile create mode 100644 net/nsh/nsh.c diff --git a/net/Kconfig b/net/Kconfig index 8614a9ccfbef..e0e7c62c88f0 100644 --- a/net/Kconfig +++ b/net/Kconfig @@ -235,6 +235,7 @@ source "net/openvswitch/Kconfig" source "net/vmw_vsock/Kconfig" source "net/netlink/Kconfig" source "net/mpls/Kconfig" +source "net/nsh/Kconfig" source "net/hsr/Kconfig" source "net/switchdev/Kconfig" source "net/l3mdev/Kconfig" diff --git a/net/Makefile b/net/Makefile index 3d3feff3643b..ae2fe2283d2f 100644 --- a/net/Makefile +++ b/net/Makefile @@ -75,6 +75,7 @@ obj-$(CONFIG_NET_IFE) += ife/ obj-$(CONFIG_OPENVSWITCH) += openvswitch/ obj-$(CONFIG_VSOCKETS) += vmw_vsock/ obj-$(CONFIG_MPLS) += mpls/ +obj-$(CONFIG_NET_NSH) += nsh/ obj-$(CONFIG_HSR) += hsr/ ifneq ($(CONFIG_NET_SWITCHDEV),) obj-y += switchdev/ diff --git a/net/nsh/Kconfig b/net/nsh/Kconfig new file mode 100644 index 000000000000..bafc3dd60c2c --- /dev/null +++ b/net/nsh/Kconfig @@ -0,0 +1,9 @@ +menuconfig NET_NSH + tristate "Network Service Header (NSH) protocol" + default n + ---help--- + Network Service Header is an implementation of Service Function + Chaining (RFC 7665). The current implementation in Linux supports + only MD type 1 and only with the openvswitch module. + + If unsure, say N. diff --git a/net/nsh/Makefile b/net/nsh/Makefile new file mode 100644 index 000000000000..c93c787385ca --- /dev/null +++ b/net/nsh/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_NET_NSH) += nsh.o diff --git a/net/nsh/nsh.c b/net/nsh/nsh.c new file mode 100644 index 000000000000..58fb827439a8 --- /dev/null +++ b/net/nsh/nsh.c @@ -0,0 +1,91 @@ +/* + * Network Service Header + * + * Copyright (c) 2017 Red Hat, Inc. -- Jiri Benc + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include + +static struct sk_buff *nsh_gso_segment(struct sk_buff *skb, + netdev_features_t features) +{ + struct sk_buff *segs = ERR_PTR(-EINVAL); + unsigned int nsh_len, mac_len; + __be16 proto; + int nhoff; + + skb_reset_network_header(skb); + + nhoff = skb->network_header - skb->mac_header; + mac_len = skb->mac_len; + + if (unlikely(!pskb_may_pull(skb, NSH_BASE_HDR_LEN))) + goto out; + nsh_len = nsh_hdr_len(nsh_hdr(skb)); + if (unlikely(!pskb_may_pull(skb, nsh_len))) + goto out; + + proto = tun_p_to_eth_p(nsh_hdr(skb)->np); + if (!proto) + goto out; + + __skb_pull(skb, nsh_len); + + skb_reset_mac_header(skb); + skb_reset_mac_len(skb); + skb->protocol = proto; + + features &= NETIF_F_SG; + segs = skb_mac_gso_segment(skb, features); + if (IS_ERR_OR_NULL(segs)) { + skb_gso_error_unwind(skb, htons(ETH_P_NSH), nsh_len, + skb->network_header - nhoff, + mac_len); + goto out; + } + + for (skb = segs; skb; skb = skb->next) { + skb->protocol = htons(ETH_P_NSH); + __skb_push(skb, nsh_len); + skb_set_mac_header(skb, -nhoff); + skb->network_header = skb->mac_header + mac_len; + skb->mac_len = mac_len; + } + +out: + return segs; +} + +static struct packet_offload nsh_packet_offload __read_mostly = { + .type = htons(ETH_P_NSH), + .priority = 15, + .callbacks = { + .gso_segment = nsh_gso_segment, + }, +}; + +static int __init nsh_init_module(void) +{ + dev_add_offload(&nsh_packet_offload); + return 0; +} + +static void __exit nsh_cleanup_module(void) +{ + dev_remove_offload(&nsh_packet_offload); +} + +module_init(nsh_init_module); +module_exit(nsh_cleanup_module); + +MODULE_AUTHOR("Jiri Benc "); +MODULE_DESCRIPTION("NSH protocol"); +MODULE_LICENSE("GPL v2"); -- 2.20.1