diff options
| -rw-r--r-- | include/net/xfrm.h | 5 | ||||
| -rw-r--r-- | net/ipv4/udp.c | 156 | ||||
| -rw-r--r-- | net/ipv4/xfrm4_input.c | 114 |
3 files changed, 133 insertions, 142 deletions
diff --git a/include/net/xfrm.h b/include/net/xfrm.h index d3a898b..ae959e9 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -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; diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index b9276f8..4ec4a25 100644 --- a/net/ipv4/udp.c +++ b/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; - } - - /* FALLTHROUGH -- pass up as UDP packet */ + /* if we're overly short, let UDP handle it */ + len = skb->len - sizeof(struct udphdr); + if (len <= 0) + goto udp; + + 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; diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c index fa1902d..2fa1082 100644 --- a/net/ipv4/xfrm4_input.c +++ b/net/ipv4/xfrm4_input.c @@ -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); |
