remcsum_unadjust((__sum16 *)ptr, grc->delta);
}
-struct skb_csum_offl_spec {
- __u16 ipv4_okay:1,
- ipv6_okay:1,
- encap_okay:1,
- ip_options_okay:1,
- ext_hdrs_okay:1,
- tcp_okay:1,
- udp_okay:1,
- sctp_okay:1,
- vlan_okay:1,
- no_encapped_ipv6:1,
- no_not_encapped:1;
-};
-
-bool __skb_csum_offload_chk(struct sk_buff *skb,
- const struct skb_csum_offl_spec *spec,
- bool *csum_encapped,
- bool csum_help);
-
-static inline bool skb_csum_offload_chk(struct sk_buff *skb,
- const struct skb_csum_offl_spec *spec,
- bool *csum_encapped,
- bool csum_help)
-{
- if (skb->ip_summed != CHECKSUM_PARTIAL)
- return false;
-
- return __skb_csum_offload_chk(skb, spec, csum_encapped, csum_help);
-}
-
-static inline bool skb_csum_offload_chk_help(struct sk_buff *skb,
- const struct skb_csum_offl_spec *spec)
-{
- bool csum_encapped;
-
- return skb_csum_offload_chk(skb, spec, &csum_encapped, true);
-}
-
-static inline bool skb_csum_off_chk_help_cmn(struct sk_buff *skb)
-{
- static const struct skb_csum_offl_spec csum_offl_spec = {
- .ipv4_okay = 1,
- .ip_options_okay = 1,
- .ipv6_okay = 1,
- .vlan_okay = 1,
- .tcp_okay = 1,
- .udp_okay = 1,
- };
-
- return skb_csum_offload_chk_help(skb, &csum_offl_spec);
-}
-
-static inline bool skb_csum_off_chk_help_cmn_v4_only(struct sk_buff *skb)
-{
- static const struct skb_csum_offl_spec csum_offl_spec = {
- .ipv4_okay = 1,
- .ip_options_okay = 1,
- .tcp_okay = 1,
- .udp_okay = 1,
- .vlan_okay = 1,
- };
-
- return skb_csum_offload_chk_help(skb, &csum_offl_spec);
-}
-
static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev,
unsigned short type,
const void *daddr, const void *saddr,
}
}
-/* Map an ethertype into IP protocol if possible */
-static inline int eproto_to_ipproto(int eproto)
-{
- switch (eproto) {
- case htons(ETH_P_IP):
- return IPPROTO_IP;
- case htons(ETH_P_IPV6):
- return IPPROTO_IPV6;
- default:
- return -1;
- }
-}
-
#ifdef CONFIG_BUG
void netdev_rx_csum_fault(struct net_device *dev);
#else
#include <linux/errqueue.h>
#include <linux/hrtimer.h>
#include <linux/netfilter_ingress.h>
-#include <linux/sctp.h>
#include <linux/crash_dump.h>
#include "net-sysfs.h"
}
EXPORT_SYMBOL(skb_checksum_help);
-/* skb_csum_offload_check - Driver helper function to determine if a device
- * with limited checksum offload capabilities is able to offload the checksum
- * for a given packet.
- *
- * Arguments:
- * skb - sk_buff for the packet in question
- * spec - contains the description of what device can offload
- * csum_encapped - returns true if the checksum being offloaded is
- * encpasulated. That is it is checksum for the transport header
- * in the inner headers.
- * checksum_help - when set indicates that helper function should
- * call skb_checksum_help if offload checks fail
- *
- * Returns:
- * true: Packet has passed the checksum checks and should be offloadable to
- * the device (a driver may still need to check for additional
- * restrictions of its device)
- * false: Checksum is not offloadable. If checksum_help was set then
- * skb_checksum_help was called to resolve checksum for non-GSO
- * packets and when IP protocol is not SCTP
- */
-bool __skb_csum_offload_chk(struct sk_buff *skb,
- const struct skb_csum_offl_spec *spec,
- bool *csum_encapped,
- bool csum_help)
-{
- struct iphdr *iph;
- struct ipv6hdr *ipv6;
- void *nhdr;
- int protocol;
- u8 ip_proto;
-
- if (skb->protocol == htons(ETH_P_8021Q) ||
- skb->protocol == htons(ETH_P_8021AD)) {
- if (!spec->vlan_okay)
- goto need_help;
- }
-
- /* We check whether the checksum refers to a transport layer checksum in
- * the outermost header or an encapsulated transport layer checksum that
- * corresponds to the inner headers of the skb. If the checksum is for
- * something else in the packet we need help.
- */
- if (skb_checksum_start_offset(skb) == skb_transport_offset(skb)) {
- /* Non-encapsulated checksum */
- protocol = eproto_to_ipproto(vlan_get_protocol(skb));
- nhdr = skb_network_header(skb);
- *csum_encapped = false;
- if (spec->no_not_encapped)
- goto need_help;
- } else if (skb->encapsulation && spec->encap_okay &&
- skb_checksum_start_offset(skb) ==
- skb_inner_transport_offset(skb)) {
- /* Encapsulated checksum */
- *csum_encapped = true;
- switch (skb->inner_protocol_type) {
- case ENCAP_TYPE_ETHER:
- protocol = eproto_to_ipproto(skb->inner_protocol);
- break;
- case ENCAP_TYPE_IPPROTO:
- protocol = skb->inner_protocol;
- break;
- }
- nhdr = skb_inner_network_header(skb);
- } else {
- goto need_help;
- }
-
- switch (protocol) {
- case IPPROTO_IP:
- if (!spec->ipv4_okay)
- goto need_help;
- iph = nhdr;
- ip_proto = iph->protocol;
- if (iph->ihl != 5 && !spec->ip_options_okay)
- goto need_help;
- break;
- case IPPROTO_IPV6:
- if (!spec->ipv6_okay)
- goto need_help;
- if (spec->no_encapped_ipv6 && *csum_encapped)
- goto need_help;
- ipv6 = nhdr;
- nhdr += sizeof(*ipv6);
- ip_proto = ipv6->nexthdr;
- break;
- default:
- goto need_help;
- }
-
-ip_proto_again:
- switch (ip_proto) {
- case IPPROTO_TCP:
- if (!spec->tcp_okay ||
- skb->csum_offset != offsetof(struct tcphdr, check))
- goto need_help;
- break;
- case IPPROTO_UDP:
- if (!spec->udp_okay ||
- skb->csum_offset != offsetof(struct udphdr, check))
- goto need_help;
- break;
- case IPPROTO_SCTP:
- if (!spec->sctp_okay ||
- skb->csum_offset != offsetof(struct sctphdr, checksum))
- goto cant_help;
- break;
- case NEXTHDR_HOP:
- case NEXTHDR_ROUTING:
- case NEXTHDR_DEST: {
- u8 *opthdr = nhdr;
-
- if (protocol != IPPROTO_IPV6 || !spec->ext_hdrs_okay)
- goto need_help;
-
- ip_proto = opthdr[0];
- nhdr += (opthdr[1] + 1) << 3;
-
- goto ip_proto_again;
- }
- default:
- goto need_help;
- }
-
- /* Passed the tests for offloading checksum */
- return true;
-
-need_help:
- if (csum_help && !skb_shinfo(skb)->gso_size)
- skb_checksum_help(skb);
-cant_help:
- return false;
-}
-EXPORT_SYMBOL(__skb_csum_offload_chk);
-
__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
{
__be16 type = skb->protocol;
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