1 /* 2 * IPV4 GSO/GRO offload support 3 * Linux INET implementation 4 * 5 * Copyright (C) 2016 secunet Security Networks AG 6 * Author: Steffen Klassert <steffen.klassert@secunet.com> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms and conditions of the GNU General Public License, 10 * version 2, as published by the Free Software Foundation. 11 * 12 * ESP GRO support 13 */ 14 15 #include <linux/skbuff.h> 16 #include <linux/init.h> 17 #include <net/protocol.h> 18 #include <crypto/aead.h> 19 #include <crypto/authenc.h> 20 #include <linux/err.h> 21 #include <linux/module.h> 22 #include <net/ip.h> 23 #include <net/xfrm.h> 24 #include <net/esp.h> 25 #include <linux/scatterlist.h> 26 #include <linux/kernel.h> 27 #include <linux/slab.h> 28 #include <linux/spinlock.h> 29 #include <net/udp.h> 30 31 static struct sk_buff **esp4_gro_receive(struct sk_buff **head, 32 struct sk_buff *skb) 33 { 34 int offset = skb_gro_offset(skb); 35 struct xfrm_offload *xo; 36 struct xfrm_state *x; 37 __be32 seq; 38 __be32 spi; 39 int err; 40 41 skb_pull(skb, offset); 42 43 if ((err = xfrm_parse_spi(skb, IPPROTO_ESP, &spi, &seq)) != 0) 44 goto out; 45 46 err = secpath_set(skb); 47 if (err) 48 goto out; 49 50 if (skb->sp->len == XFRM_MAX_DEPTH) 51 goto out; 52 53 x = xfrm_state_lookup(dev_net(skb->dev), skb->mark, 54 (xfrm_address_t *)&ip_hdr(skb)->daddr, 55 spi, IPPROTO_ESP, AF_INET); 56 if (!x) 57 goto out; 58 59 skb->sp->xvec[skb->sp->len++] = x; 60 skb->sp->olen++; 61 62 xo = xfrm_offload(skb); 63 if (!xo) { 64 xfrm_state_put(x); 65 goto out; 66 } 67 xo->flags |= XFRM_GRO; 68 69 XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = NULL; 70 XFRM_SPI_SKB_CB(skb)->family = AF_INET; 71 XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr); 72 XFRM_SPI_SKB_CB(skb)->seq = seq; 73 74 /* We don't need to handle errors from xfrm_input, it does all 75 * the error handling and frees the resources on error. */ 76 xfrm_input(skb, IPPROTO_ESP, spi, -2); 77 78 return ERR_PTR(-EINPROGRESS); 79 out: 80 skb_push(skb, offset); 81 NAPI_GRO_CB(skb)->same_flow = 0; 82 NAPI_GRO_CB(skb)->flush = 1; 83 84 return NULL; 85 } 86 87 static const struct net_offload esp4_offload = { 88 .callbacks = { 89 .gro_receive = esp4_gro_receive, 90 }, 91 }; 92 93 static int __init esp4_offload_init(void) 94 { 95 return inet_add_offload(&esp4_offload, IPPROTO_ESP); 96 } 97 98 static void __exit esp4_offload_exit(void) 99 { 100 inet_del_offload(&esp4_offload, IPPROTO_ESP); 101 } 102 103 module_init(esp4_offload_init); 104 module_exit(esp4_offload_exit); 105 MODULE_LICENSE("GPL"); 106 MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>"); 107