mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-28 14:44:10 +08:00
[UDP]: Cleanup UDP encapsulation code
This cleanup fell out after adding L2TP support where a new encap_rcv funcptr was added to struct udp_sock. Have XFRM use the new encap_rcv funcptr, which allows us to move the XFRM encap code from udp.c into xfrm4_input.c. Make xfrm4_rcv_encap() static since it is no longer called externally. Signed-off-by: James Chapman <jchapman@katalix.com> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
James Chapman
David S. Miller
parent
93cce3d365
commit
067b207b28
@ -1003,7 +1003,7 @@ extern int xfrm6_find_1stfragopt(struct xfrm_state *x, struct sk_buff *skb,
|
||||
u8 **prevhdr);
|
||||
|
||||
#ifdef CONFIG_XFRM
|
||||
extern int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type);
|
||||
extern int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb);
|
||||
extern int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen);
|
||||
extern int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family);
|
||||
#else
|
||||
@ -1012,12 +1012,13 @@ static inline int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optv
|
||||
return -ENOPROTOOPT;
|
||||
}
|
||||
|
||||
static inline int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
|
||||
static inline int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb)
|
||||
{
|
||||
/* should not happen */
|
||||
kfree_skb(skb);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static inline int xfrm_dst_lookup(struct xfrm_dst **dst, struct flowi *fl, unsigned short family)
|
||||
{
|
||||
return -EINVAL;
|
||||
|
||||
154
net/ipv4/udp.c
154
net/ipv4/udp.c
@ -920,108 +920,6 @@ int udp_disconnect(struct sock *sk, int flags)
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* return:
|
||||
* 1 if the UDP system should process it
|
||||
* 0 if we should drop this packet
|
||||
* -1 if it should get processed by xfrm4_rcv_encap
|
||||
* -2 if it should get processed by l2tp
|
||||
*/
|
||||
static int udp_encap_rcv(struct sock * sk, struct sk_buff *skb)
|
||||
{
|
||||
struct udp_sock *up = udp_sk(sk);
|
||||
struct udphdr *uh;
|
||||
struct iphdr *iph;
|
||||
int iphlen, len;
|
||||
|
||||
__u8 *udpdata;
|
||||
__be32 *udpdata32;
|
||||
__u16 encap_type = up->encap_type;
|
||||
|
||||
/* if we're overly short, let UDP handle it */
|
||||
len = skb->len - sizeof(struct udphdr);
|
||||
if (len <= 0)
|
||||
return 1;
|
||||
|
||||
/* if this is not encapsulated socket, then just return now */
|
||||
if (!encap_type)
|
||||
return 1;
|
||||
|
||||
/* If this is a paged skb, make sure we pull up
|
||||
* whatever data we need to look at. */
|
||||
if (!pskb_may_pull(skb, sizeof(struct udphdr) + min(len, 8)))
|
||||
return 1;
|
||||
|
||||
/* Now we can get the pointers */
|
||||
uh = udp_hdr(skb);
|
||||
udpdata = (__u8 *)uh + sizeof(struct udphdr);
|
||||
udpdata32 = (__be32 *)udpdata;
|
||||
|
||||
switch (encap_type) {
|
||||
default:
|
||||
case UDP_ENCAP_ESPINUDP:
|
||||
/* Check if this is a keepalive packet. If so, eat it. */
|
||||
if (len == 1 && udpdata[0] == 0xff) {
|
||||
return 0;
|
||||
} else if (len > sizeof(struct ip_esp_hdr) && udpdata32[0] != 0) {
|
||||
/* ESP Packet without Non-ESP header */
|
||||
len = sizeof(struct udphdr);
|
||||
} else
|
||||
/* Must be an IKE packet.. pass it through */
|
||||
return 1;
|
||||
break;
|
||||
case UDP_ENCAP_ESPINUDP_NON_IKE:
|
||||
/* Check if this is a keepalive packet. If so, eat it. */
|
||||
if (len == 1 && udpdata[0] == 0xff) {
|
||||
return 0;
|
||||
} else if (len > 2 * sizeof(u32) + sizeof(struct ip_esp_hdr) &&
|
||||
udpdata32[0] == 0 && udpdata32[1] == 0) {
|
||||
|
||||
/* ESP Packet with Non-IKE marker */
|
||||
len = sizeof(struct udphdr) + 2 * sizeof(u32);
|
||||
} else
|
||||
/* Must be an IKE packet.. pass it through */
|
||||
return 1;
|
||||
break;
|
||||
case UDP_ENCAP_L2TPINUDP:
|
||||
/* Let caller know to send this to l2tp */
|
||||
return -2;
|
||||
}
|
||||
|
||||
#ifndef CONFIG_XFRM
|
||||
return 1;
|
||||
#else
|
||||
/* At this point we are sure that this is an ESPinUDP packet,
|
||||
* so we need to remove 'len' bytes from the packet (the UDP
|
||||
* header and optional ESP marker bytes) and then modify the
|
||||
* protocol to ESP, and then call into the transform receiver.
|
||||
*/
|
||||
if (skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
|
||||
return 0;
|
||||
|
||||
/* Now we can update and verify the packet length... */
|
||||
iph = ip_hdr(skb);
|
||||
iphlen = iph->ihl << 2;
|
||||
iph->tot_len = htons(ntohs(iph->tot_len) - len);
|
||||
if (skb->len < iphlen + len) {
|
||||
/* packet is too small!?! */
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* pull the data buffer up to the ESP header and set the
|
||||
* transport header to point to ESP. Keep UDP on the stack
|
||||
* for later.
|
||||
*/
|
||||
__skb_pull(skb, len);
|
||||
skb_reset_transport_header(skb);
|
||||
|
||||
/* modify the protocol (it's ESP!) */
|
||||
iph->protocol = IPPROTO_ESP;
|
||||
|
||||
/* and let the caller know to send this into the ESP processor... */
|
||||
return -1;
|
||||
#endif
|
||||
}
|
||||
|
||||
/* returns:
|
||||
* -1: error
|
||||
* 0: success
|
||||
@ -1044,44 +942,36 @@ int udp_queue_rcv_skb(struct sock * sk, struct sk_buff *skb)
|
||||
|
||||
if (up->encap_type) {
|
||||
/*
|
||||
* This is an encapsulation socket, so let's see if this is
|
||||
* an encapsulated packet.
|
||||
* If it's a keepalive packet, then just eat it.
|
||||
* If it's an encapsulateed packet, then pass it to the
|
||||
* IPsec xfrm input and return the response
|
||||
* appropriately. Otherwise, just fall through and
|
||||
* pass this up the UDP socket.
|
||||
* This is an encapsulation socket so pass the skb to
|
||||
* the socket's udp_encap_rcv() hook. Otherwise, just
|
||||
* fall through and pass this up the UDP socket.
|
||||
* up->encap_rcv() returns the following value:
|
||||
* =0 if skb was successfully passed to the encap
|
||||
* handler or was discarded by it.
|
||||
* >0 if skb should be passed on to UDP.
|
||||
* <0 if skb should be resubmitted as proto -N
|
||||
*/
|
||||
int ret;
|
||||
unsigned int len;
|
||||
|
||||
ret = udp_encap_rcv(sk, skb);
|
||||
if (ret == 0) {
|
||||
/* Eat the packet .. */
|
||||
kfree_skb(skb);
|
||||
return 0;
|
||||
}
|
||||
if (ret == -1) {
|
||||
/* process the ESP packet */
|
||||
ret = xfrm4_rcv_encap(skb, up->encap_type);
|
||||
UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag);
|
||||
return -ret;
|
||||
}
|
||||
if (ret == -2) {
|
||||
/* process the L2TP packet */
|
||||
if (up->encap_rcv != NULL) {
|
||||
ret = (*up->encap_rcv)(sk, skb);
|
||||
if (ret <= 0) {
|
||||
UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag);
|
||||
return ret;
|
||||
}
|
||||
/* if we're overly short, let UDP handle it */
|
||||
len = skb->len - sizeof(struct udphdr);
|
||||
if (len <= 0)
|
||||
goto udp;
|
||||
|
||||
/* FALLTHROUGH -- pass up as UDP packet */
|
||||
if (up->encap_rcv != NULL) {
|
||||
int ret;
|
||||
|
||||
ret = (*up->encap_rcv)(sk, skb);
|
||||
if (ret <= 0) {
|
||||
UDP_INC_STATS_BH(UDP_MIB_INDATAGRAMS, up->pcflag);
|
||||
return -ret;
|
||||
}
|
||||
}
|
||||
|
||||
/* FALLTHROUGH -- it's a UDP Packet */
|
||||
}
|
||||
|
||||
udp:
|
||||
/*
|
||||
* UDP-Lite specific tests, ignored on UDP sockets
|
||||
*/
|
||||
@ -1367,6 +1257,8 @@ int udp_lib_setsockopt(struct sock *sk, int level, int optname,
|
||||
case 0:
|
||||
case UDP_ENCAP_ESPINUDP:
|
||||
case UDP_ENCAP_ESPINUDP_NON_IKE:
|
||||
up->encap_rcv = xfrm4_udp_encap_rcv;
|
||||
/* FALLTHROUGH */
|
||||
case UDP_ENCAP_L2TPINUDP:
|
||||
up->encap_type = val;
|
||||
break;
|
||||
|
||||
@ -16,13 +16,6 @@
|
||||
#include <net/ip.h>
|
||||
#include <net/xfrm.h>
|
||||
|
||||
int xfrm4_rcv(struct sk_buff *skb)
|
||||
{
|
||||
return xfrm4_rcv_encap(skb, 0);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(xfrm4_rcv);
|
||||
|
||||
static int xfrm4_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
|
||||
{
|
||||
switch (nexthdr) {
|
||||
@ -53,7 +46,7 @@ drop:
|
||||
}
|
||||
#endif
|
||||
|
||||
int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
|
||||
static int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
|
||||
{
|
||||
__be32 spi, seq;
|
||||
struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH];
|
||||
@ -167,3 +160,108 @@ drop:
|
||||
kfree_skb(skb);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* If it's a keepalive packet, then just eat it.
|
||||
* If it's an encapsulated packet, then pass it to the
|
||||
* IPsec xfrm input.
|
||||
* Returns 0 if skb passed to xfrm or was dropped.
|
||||
* Returns >0 if skb should be passed to UDP.
|
||||
* Returns <0 if skb should be resubmitted (-ret is protocol)
|
||||
*/
|
||||
int xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb)
|
||||
{
|
||||
struct udp_sock *up = udp_sk(sk);
|
||||
struct udphdr *uh;
|
||||
struct iphdr *iph;
|
||||
int iphlen, len;
|
||||
int ret;
|
||||
|
||||
__u8 *udpdata;
|
||||
__be32 *udpdata32;
|
||||
__u16 encap_type = up->encap_type;
|
||||
|
||||
/* if this is not encapsulated socket, then just return now */
|
||||
if (!encap_type)
|
||||
return 1;
|
||||
|
||||
/* If this is a paged skb, make sure we pull up
|
||||
* whatever data we need to look at. */
|
||||
len = skb->len - sizeof(struct udphdr);
|
||||
if (!pskb_may_pull(skb, sizeof(struct udphdr) + min(len, 8)))
|
||||
return 1;
|
||||
|
||||
/* Now we can get the pointers */
|
||||
uh = udp_hdr(skb);
|
||||
udpdata = (__u8 *)uh + sizeof(struct udphdr);
|
||||
udpdata32 = (__be32 *)udpdata;
|
||||
|
||||
switch (encap_type) {
|
||||
default:
|
||||
case UDP_ENCAP_ESPINUDP:
|
||||
/* Check if this is a keepalive packet. If so, eat it. */
|
||||
if (len == 1 && udpdata[0] == 0xff) {
|
||||
goto drop;
|
||||
} else if (len > sizeof(struct ip_esp_hdr) && udpdata32[0] != 0) {
|
||||
/* ESP Packet without Non-ESP header */
|
||||
len = sizeof(struct udphdr);
|
||||
} else
|
||||
/* Must be an IKE packet.. pass it through */
|
||||
return 1;
|
||||
break;
|
||||
case UDP_ENCAP_ESPINUDP_NON_IKE:
|
||||
/* Check if this is a keepalive packet. If so, eat it. */
|
||||
if (len == 1 && udpdata[0] == 0xff) {
|
||||
goto drop;
|
||||
} else if (len > 2 * sizeof(u32) + sizeof(struct ip_esp_hdr) &&
|
||||
udpdata32[0] == 0 && udpdata32[1] == 0) {
|
||||
|
||||
/* ESP Packet with Non-IKE marker */
|
||||
len = sizeof(struct udphdr) + 2 * sizeof(u32);
|
||||
} else
|
||||
/* Must be an IKE packet.. pass it through */
|
||||
return 1;
|
||||
break;
|
||||
}
|
||||
|
||||
/* At this point we are sure that this is an ESPinUDP packet,
|
||||
* so we need to remove 'len' bytes from the packet (the UDP
|
||||
* header and optional ESP marker bytes) and then modify the
|
||||
* protocol to ESP, and then call into the transform receiver.
|
||||
*/
|
||||
if (skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
|
||||
goto drop;
|
||||
|
||||
/* Now we can update and verify the packet length... */
|
||||
iph = ip_hdr(skb);
|
||||
iphlen = iph->ihl << 2;
|
||||
iph->tot_len = htons(ntohs(iph->tot_len) - len);
|
||||
if (skb->len < iphlen + len) {
|
||||
/* packet is too small!?! */
|
||||
goto drop;
|
||||
}
|
||||
|
||||
/* pull the data buffer up to the ESP header and set the
|
||||
* transport header to point to ESP. Keep UDP on the stack
|
||||
* for later.
|
||||
*/
|
||||
__skb_pull(skb, len);
|
||||
skb_reset_transport_header(skb);
|
||||
|
||||
/* modify the protocol (it's ESP!) */
|
||||
iph->protocol = IPPROTO_ESP;
|
||||
|
||||
/* process ESP */
|
||||
ret = xfrm4_rcv_encap(skb, encap_type);
|
||||
return ret;
|
||||
|
||||
drop:
|
||||
kfree_skb(skb);
|
||||
return 0;
|
||||
}
|
||||
|
||||
int xfrm4_rcv(struct sk_buff *skb)
|
||||
{
|
||||
return xfrm4_rcv_encap(skb, 0);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(xfrm4_rcv);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user