projects / mirror_ovs.git / blame
| Commit | Line | Data |
|---|---|---|
| 96b82f6d YY |
1 | /* |
| 2 | * Network Service Header | |
| 3 | * | |
| 4 | * Copyright (c) 2017 Red Hat, Inc. -- Jiri Benc <jbenc@redhat.com> | |
| 5 | * | |
| 6 | * This program is free software; you can redistribute it and/or modify | |
| 7 | * it under the terms of the GNU General Public License version 2 as | |
| 8 | * published by the Free Software Foundation. | |
| 9 | */ | |
| 10 | ||
| 11 | #include <linux/netdevice.h> | |
| 12 | #include <linux/skbuff.h> | |
| 13 | #include <net/nsh.h> | |
| 14 | #include <net/tun_proto.h> | |
| 15 | ||
| 16 | int ovs_nsh_push(struct sk_buff *skb, const struct nshhdr *pushed_nh) | |
| 17 | { | |
| 18 | struct nshhdr *nh; | |
| 19 | size_t length = nsh_hdr_len(pushed_nh); | |
| 20 | u8 next_proto; | |
| 21 | ||
| 22 | if (skb->mac_len) { | |
| 23 | next_proto = TUN_P_ETHERNET; | |
| 24 | } else { | |
| 25 | next_proto = tun_p_from_eth_p(skb->protocol); | |
| 26 | if (!next_proto) | |
| 27 | return -EAFNOSUPPORT; | |
| 28 | } | |
| 29 | ||
| 30 | /* Add the NSH header */ | |
| 31 | if (skb_cow_head(skb, length) < 0) | |
| 32 | return -ENOMEM; | |
| 33 | ||
| 34 | skb_push(skb, length); | |
| 35 | nh = (struct nshhdr *)(skb->data); | |
| 36 | memcpy(nh, pushed_nh, length); | |
| 37 | nh->np = next_proto; | |
| 38 | skb_postpush_rcsum(skb, nh, length); | |
| 39 | ||
| 40 | skb->protocol = htons(ETH_P_NSH); | |
| 41 | skb_reset_mac_header(skb); | |
| 42 | skb_reset_network_header(skb); | |
| 43 | skb_reset_mac_len(skb); | |
| 44 | ||
| 45 | return 0; | |
| 46 | } | |
| 47 | EXPORT_SYMBOL_GPL(ovs_nsh_push); | |
| 48 | ||
| 49 | int ovs_nsh_pop(struct sk_buff *skb) | |
| 50 | { | |
| 51 | struct nshhdr *nh; | |
| 52 | size_t length; | |
| 53 | __be16 inner_proto; | |
| 54 | ||
| 55 | if (!pskb_may_pull(skb, NSH_BASE_HDR_LEN)) | |
| 56 | return -ENOMEM; | |
| 57 | nh = (struct nshhdr *)(skb->data); | |
| 58 | length = nsh_hdr_len(nh); | |
| 59 | inner_proto = tun_p_to_eth_p(nh->np); | |
| 60 | if (!pskb_may_pull(skb, length)) | |
| 61 | return -ENOMEM; | |
| 62 | ||
| 63 | if (!inner_proto) | |
| 64 | return -EAFNOSUPPORT; | |
| 65 | ||
| 66 | skb_pull_rcsum(skb, length); | |
| 67 | skb_reset_mac_header(skb); | |
| 68 | skb_reset_network_header(skb); | |
| 69 | skb_reset_mac_len(skb); | |
| 70 | skb->protocol = inner_proto; | |
| 71 | ||
| 72 | return 0; | |
| 73 | } | |
| 74 | EXPORT_SYMBOL_GPL(ovs_nsh_pop); | |
| 75 | ||
| 76 | static struct sk_buff *nsh_gso_segment(struct sk_buff *skb, | |
| 77 | netdev_features_t features) | |
| 78 | { | |
| 79 | struct sk_buff *segs = ERR_PTR(-EINVAL); | |
| 80 | unsigned int nsh_len, mac_len; | |
| 81 | __be16 proto; | |
| 82 | int nhoff; | |
| 83 | ||
| 84 | skb_reset_network_header(skb); | |
| 85 | ||
| 86 | nhoff = skb->network_header - skb->mac_header; | |
| 87 | mac_len = skb->mac_len; | |
| 88 | ||
| 89 | if (unlikely(!pskb_may_pull(skb, NSH_BASE_HDR_LEN))) | |
| 90 | goto out; | |
| 91 | nsh_len = nsh_hdr_len(nsh_hdr(skb)); | |
| 92 | if (unlikely(!pskb_may_pull(skb, nsh_len))) | |
| 93 | goto out; | |
| 94 | ||
| 95 | proto = tun_p_to_eth_p(nsh_hdr(skb)->np); | |
| 96 | if (!proto) | |
| 97 | goto out; | |
| 98 | ||
| 99 | __skb_pull(skb, nsh_len); | |
| 100 | ||
| 101 | skb_reset_mac_header(skb); | |
| 102 | skb_reset_mac_len(skb); | |
| 103 | skb->protocol = proto; | |
| 104 | ||
| 105 | features &= NETIF_F_SG; | |
| 106 | segs = skb_mac_gso_segment(skb, features); | |
| 107 | if (IS_ERR_OR_NULL(segs)) { | |
| 108 | skb_gso_error_unwind(skb, htons(ETH_P_NSH), nsh_len, | |
| 109 | skb->network_header - nhoff, | |
| 110 | mac_len); | |
| 111 | goto out; | |
| 112 | } | |
| 113 | ||
| 114 | for (skb = segs; skb; skb = skb->next) { | |
| 115 | skb->protocol = htons(ETH_P_NSH); | |
| 116 | __skb_push(skb, nsh_len); | |
| 117 | skb_set_mac_header(skb, -nhoff); | |
| 118 | skb->network_header = skb->mac_header + mac_len; | |
| 119 | skb->mac_len = mac_len; | |
| 120 | } | |
| 121 | ||
| 122 | out: | |
| 123 | return segs; | |
| 124 | } | |
| 125 | ||
| 126 | static struct packet_offload nsh_packet_offload __read_mostly = { | |
| 127 | .type = htons(ETH_P_NSH), | |
| 128 | .callbacks = { | |
| 129 | .gso_segment = nsh_gso_segment, | |
| 130 | }, | |
| 131 | }; | |
| 132 | ||
| 133 | int ovs_nsh_init(void) | |
| 134 | { | |
| 135 | dev_add_offload(&nsh_packet_offload); | |
| 136 | return 0; | |
| 137 | } | |
| 138 | ||
| 139 | void ovs_nsh_cleanup(void) | |
| 140 | { | |
| 141 | dev_remove_offload(&nsh_packet_offload); | |
| 142 | } |