Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * IP Payload Compression Protocol (IPComp) - RFC3173.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright (c) 2003 James Morris <jmorris@intercode.com.au>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7)  * Todo:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8)  *   - Tunable compression parameters.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9)  *   - Compression stats.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10)  *   - Adaptive compression.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/rtnetlink.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <net/ip.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <net/xfrm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include <net/icmp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) #include <net/ipcomp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) #include <net/protocol.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #include <net/sock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) static int ipcomp4_err(struct sk_buff *skb, u32 info)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 	struct net *net = dev_net(skb->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 	__be32 spi;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 	const struct iphdr *iph = (const struct iphdr *)skb->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 	struct ip_comp_hdr *ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 	struct xfrm_state *x;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 	switch (icmp_hdr(skb)->type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 	case ICMP_DEST_UNREACH:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 		if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 			return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	case ICMP_REDIRECT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 	default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 	spi = htonl(ntohs(ipch->cpi));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 			      spi, IPPROTO_COMP, AF_INET);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	if (!x)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 		ipv4_update_pmtu(skb, net, info, 0, IPPROTO_COMP);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 		ipv4_redirect(skb, net, 0, IPPROTO_COMP);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 	xfrm_state_put(x);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) /* We always hold one tunnel user reference to indicate a tunnel */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) static struct xfrm_state *ipcomp_tunnel_create(struct xfrm_state *x)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	struct net *net = xs_net(x);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	struct xfrm_state *t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	t = xfrm_state_alloc(net);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	if (!t)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 	t->id.proto = IPPROTO_IPIP;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 	t->id.spi = x->props.saddr.a4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	t->id.daddr.a4 = x->id.daddr.a4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 	memcpy(&t->sel, &x->sel, sizeof(t->sel));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 	t->props.family = AF_INET;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	t->props.mode = x->props.mode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 	t->props.saddr.a4 = x->props.saddr.a4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 	t->props.flags = x->props.flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 	t->props.extra_flags = x->props.extra_flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 	memcpy(&t->mark, &x->mark, sizeof(t->mark));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 	t->if_id = x->if_id;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	if (xfrm_init_state(t))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 		goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 	atomic_set(&t->tunnel_users, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 	return t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) error:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	t->km.state = XFRM_STATE_DEAD;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	xfrm_state_put(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	t = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92)  * Must be protected by xfrm_cfg_mutex.  State and tunnel user references are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93)  * always incremented on success.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) static int ipcomp_tunnel_attach(struct xfrm_state *x)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 	struct net *net = xs_net(x);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 	int err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	struct xfrm_state *t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 	u32 mark = x->mark.v & x->mark.m;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 	t = xfrm_state_lookup(net, mark, (xfrm_address_t *)&x->id.daddr.a4,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 			      x->props.saddr.a4, IPPROTO_IPIP, AF_INET);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 	if (!t) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 		t = ipcomp_tunnel_create(x);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 		if (!t) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 			err = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 		xfrm_state_insert(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 		xfrm_state_hold(t);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	x->tunnel = t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 	atomic_inc(&t->tunnel_users);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) static int ipcomp4_init_state(struct xfrm_state *x)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	int err = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 	x->props.header_len = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	switch (x->props.mode) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 	case XFRM_MODE_TRANSPORT:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	case XFRM_MODE_TUNNEL:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 		x->props.header_len += sizeof(struct iphdr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 	default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 	err = ipcomp_init_state(x);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 	if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 	if (x->props.mode == XFRM_MODE_TUNNEL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 		err = ipcomp_tunnel_attach(x);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 		if (err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 			goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 	err = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) static int ipcomp4_rcv_cb(struct sk_buff *skb, int err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) static const struct xfrm_type ipcomp_type = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	.description	= "IPCOMP4",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 	.owner		= THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	.proto	     	= IPPROTO_COMP,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	.init_state	= ipcomp4_init_state,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 	.destructor	= ipcomp_destroy,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 	.input		= ipcomp_input,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	.output		= ipcomp_output
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) static struct xfrm4_protocol ipcomp4_protocol = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	.handler	=	xfrm4_rcv,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	.input_handler	=	xfrm_input,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	.cb_handler	=	ipcomp4_rcv_cb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 	.err_handler	=	ipcomp4_err,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 	.priority	=	0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) static int __init ipcomp4_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 	if (xfrm_register_type(&ipcomp_type, AF_INET) < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 		pr_info("%s: can't add xfrm type\n", __func__);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 		return -EAGAIN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 	if (xfrm4_protocol_register(&ipcomp4_protocol, IPPROTO_COMP) < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 		pr_info("%s: can't add protocol\n", __func__);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 		xfrm_unregister_type(&ipcomp_type, AF_INET);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 		return -EAGAIN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) static void __exit ipcomp4_fini(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 	if (xfrm4_protocol_deregister(&ipcomp4_protocol, IPPROTO_COMP) < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 		pr_info("%s: can't remove protocol\n", __func__);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 	xfrm_unregister_type(&ipcomp_type, AF_INET);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) module_init(ipcomp4_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) module_exit(ipcomp4_fini);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp/IPv4) - RFC3173");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_COMP);