#include <net/dst.h>
#include <net/sock.h>
#include <net/checksum.h>
+#include <net/ip6_checksum.h>
#include <net/xfrm.h>
#include <asm/uaccess.h>
new->inner_network_header = old->inner_network_header;
new->inner_mac_header = old->inner_mac_header;
skb_dst_copy(new, old);
- new->rxhash = old->rxhash;
+ skb_copy_hash(new, old);
new->ooo_okay = old->ooo_okay;
- new->l4_rxhash = old->l4_rxhash;
new->no_fcs = old->no_fcs;
new->encapsulation = old->encapsulation;
#ifdef CONFIG_XFRM
}
EXPORT_SYMBOL(skb_copy_and_csum_bits);
+ /**
+ * skb_zerocopy_headlen - Calculate headroom needed for skb_zerocopy()
+ * @from: source buffer
+ *
+ * Calculates the amount of linear headroom needed in the 'to' skb passed
+ * into skb_zerocopy().
+ */
+unsigned int
+skb_zerocopy_headlen(const struct sk_buff *from)
+{
+ unsigned int hlen = 0;
+
+ if (!from->head_frag ||
+ skb_headlen(from) < L1_CACHE_BYTES ||
+ skb_shinfo(from)->nr_frags >= MAX_SKB_FRAGS)
+ hlen = skb_headlen(from);
+
+ if (skb_has_frag_list(from))
+ hlen = from->len;
+
+ return hlen;
+}
+EXPORT_SYMBOL_GPL(skb_zerocopy_headlen);
+
+/**
+ * skb_zerocopy - Zero copy skb to skb
+ * @to: destination buffer
+ * @source: source buffer
+ * @len: number of bytes to copy from source buffer
+ * @hlen: size of linear headroom in destination buffer
+ *
+ * Copies up to `len` bytes from `from` to `to` by creating references
+ * to the frags in the source buffer.
+ *
+ * The `hlen` as calculated by skb_zerocopy_headlen() specifies the
+ * headroom in the `to` buffer.
+ */
+void
+skb_zerocopy(struct sk_buff *to, const struct sk_buff *from, int len, int hlen)
+{
+ int i, j = 0;
+ int plen = 0; /* length of skb->head fragment */
+ struct page *page;
+ unsigned int offset;
+
+ BUG_ON(!from->head_frag && !hlen);
+
+ /* dont bother with small payloads */
+ if (len <= skb_tailroom(to)) {
+ skb_copy_bits(from, 0, skb_put(to, len), len);
+ return;
+ }
+
+ if (hlen) {
+ skb_copy_bits(from, 0, skb_put(to, hlen), hlen);
+ len -= hlen;
+ } else {
+ plen = min_t(int, skb_headlen(from), len);
+ if (plen) {
+ page = virt_to_head_page(from->head);
+ offset = from->data - (unsigned char *)page_address(page);
+ __skb_fill_page_desc(to, 0, page, offset, plen);
+ get_page(page);
+ j = 1;
+ len -= plen;
+ }
+ }
+
+ to->truesize += len + plen;
+ to->len += len + plen;
+ to->data_len += len + plen;
+
+ for (i = 0; i < skb_shinfo(from)->nr_frags; i++) {
+ if (!len)
+ break;
+ skb_shinfo(to)->frags[j] = skb_shinfo(from)->frags[i];
+ skb_shinfo(to)->frags[j].size = min_t(int, skb_shinfo(to)->frags[j].size, len);
+ len -= skb_shinfo(to)->frags[j].size;
+ skb_frag_ref(to, j);
+ j++;
+ }
+ skb_shinfo(to)->nr_frags = j;
+}
+EXPORT_SYMBOL_GPL(skb_zerocopy);
+
void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to)
{
__wsum csum;
return segs;
err:
- while ((skb = segs)) {
- segs = skb->next;
- kfree_skb(skb);
- }
+ kfree_skb_list(segs);
return ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(skb_segment);
}
EXPORT_SYMBOL_GPL(skb_partial_csum_set);
+static int skb_maybe_pull_tail(struct sk_buff *skb, unsigned int len,
+ unsigned int max)
+{
+ if (skb_headlen(skb) >= len)
+ return 0;
+
+ /* If we need to pullup then pullup to the max, so we
+ * won't need to do it again.
+ */
+ if (max > skb->len)
+ max = skb->len;
+
+ if (__pskb_pull_tail(skb, max - skb_headlen(skb)) == NULL)
+ return -ENOMEM;
+
+ if (skb_headlen(skb) < len)
+ return -EPROTO;
+
+ return 0;
+}
+
+/* This value should be large enough to cover a tagged ethernet header plus
+ * maximally sized IP and TCP or UDP headers.
+ */
+#define MAX_IP_HDR_LEN 128
+
+static int skb_checksum_setup_ip(struct sk_buff *skb, bool recalculate)
+{
+ unsigned int off;
+ bool fragment;
+ int err;
+
+ fragment = false;
+
+ err = skb_maybe_pull_tail(skb,
+ sizeof(struct iphdr),
+ MAX_IP_HDR_LEN);
+ if (err < 0)
+ goto out;
+
+ if (ip_hdr(skb)->frag_off & htons(IP_OFFSET | IP_MF))
+ fragment = true;
+
+ off = ip_hdrlen(skb);
+
+ err = -EPROTO;
+
+ if (fragment)
+ goto out;
+
+ switch (ip_hdr(skb)->protocol) {
+ case IPPROTO_TCP:
+ err = skb_maybe_pull_tail(skb,
+ off + sizeof(struct tcphdr),
+ MAX_IP_HDR_LEN);
+ if (err < 0)
+ goto out;
+
+ if (!skb_partial_csum_set(skb, off,
+ offsetof(struct tcphdr, check))) {
+ err = -EPROTO;
+ goto out;
+ }
+
+ if (recalculate)
+ tcp_hdr(skb)->check =
+ ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
+ ip_hdr(skb)->daddr,
+ skb->len - off,
+ IPPROTO_TCP, 0);
+ break;
+ case IPPROTO_UDP:
+ err = skb_maybe_pull_tail(skb,
+ off + sizeof(struct udphdr),
+ MAX_IP_HDR_LEN);
+ if (err < 0)
+ goto out;
+
+ if (!skb_partial_csum_set(skb, off,
+ offsetof(struct udphdr, check))) {
+ err = -EPROTO;
+ goto out;
+ }
+
+ if (recalculate)
+ udp_hdr(skb)->check =
+ ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
+ ip_hdr(skb)->daddr,
+ skb->len - off,
+ IPPROTO_UDP, 0);
+ break;
+ default:
+ goto out;
+ }
+
+ err = 0;
+
+out:
+ return err;
+}
+
+/* This value should be large enough to cover a tagged ethernet header plus
+ * an IPv6 header, all options, and a maximal TCP or UDP header.
+ */
+#define MAX_IPV6_HDR_LEN 256
+
+#define OPT_HDR(type, skb, off) \
+ (type *)(skb_network_header(skb) + (off))
+
+static int skb_checksum_setup_ipv6(struct sk_buff *skb, bool recalculate)
+{
+ int err;
+ u8 nexthdr;
+ unsigned int off;
+ unsigned int len;
+ bool fragment;
+ bool done;
+
+ fragment = false;
+ done = false;
+
+ off = sizeof(struct ipv6hdr);
+
+ err = skb_maybe_pull_tail(skb, off, MAX_IPV6_HDR_LEN);
+ if (err < 0)
+ goto out;
+
+ nexthdr = ipv6_hdr(skb)->nexthdr;
+
+ len = sizeof(struct ipv6hdr) + ntohs(ipv6_hdr(skb)->payload_len);
+ while (off <= len && !done) {
+ switch (nexthdr) {
+ case IPPROTO_DSTOPTS:
+ case IPPROTO_HOPOPTS:
+ case IPPROTO_ROUTING: {
+ struct ipv6_opt_hdr *hp;
+
+ err = skb_maybe_pull_tail(skb,
+ off +
+ sizeof(struct ipv6_opt_hdr),
+ MAX_IPV6_HDR_LEN);
+ if (err < 0)
+ goto out;
+
+ hp = OPT_HDR(struct ipv6_opt_hdr, skb, off);
+ nexthdr = hp->nexthdr;
+ off += ipv6_optlen(hp);
+ break;
+ }
+ case IPPROTO_AH: {
+ struct ip_auth_hdr *hp;
+
+ err = skb_maybe_pull_tail(skb,
+ off +
+ sizeof(struct ip_auth_hdr),
+ MAX_IPV6_HDR_LEN);
+ if (err < 0)
+ goto out;
+
+ hp = OPT_HDR(struct ip_auth_hdr, skb, off);
+ nexthdr = hp->nexthdr;
+ off += ipv6_authlen(hp);
+ break;
+ }
+ case IPPROTO_FRAGMENT: {
+ struct frag_hdr *hp;
+
+ err = skb_maybe_pull_tail(skb,
+ off +
+ sizeof(struct frag_hdr),
+ MAX_IPV6_HDR_LEN);
+ if (err < 0)
+ goto out;
+
+ hp = OPT_HDR(struct frag_hdr, skb, off);
+
+ if (hp->frag_off & htons(IP6_OFFSET | IP6_MF))
+ fragment = true;
+
+ nexthdr = hp->nexthdr;
+ off += sizeof(struct frag_hdr);
+ break;
+ }
+ default:
+ done = true;
+ break;
+ }
+ }
+
+ err = -EPROTO;
+
+ if (!done || fragment)
+ goto out;
+
+ switch (nexthdr) {
+ case IPPROTO_TCP:
+ err = skb_maybe_pull_tail(skb,
+ off + sizeof(struct tcphdr),
+ MAX_IPV6_HDR_LEN);
+ if (err < 0)
+ goto out;
+
+ if (!skb_partial_csum_set(skb, off,
+ offsetof(struct tcphdr, check))) {
+ err = -EPROTO;
+ goto out;
+ }
+
+ if (recalculate)
+ tcp_hdr(skb)->check =
+ ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
+ &ipv6_hdr(skb)->daddr,
+ skb->len - off,
+ IPPROTO_TCP, 0);
+ break;
+ case IPPROTO_UDP:
+ err = skb_maybe_pull_tail(skb,
+ off + sizeof(struct udphdr),
+ MAX_IPV6_HDR_LEN);
+ if (err < 0)
+ goto out;
+
+ if (!skb_partial_csum_set(skb, off,
+ offsetof(struct udphdr, check))) {
+ err = -EPROTO;
+ goto out;
+ }
+
+ if (recalculate)
+ udp_hdr(skb)->check =
+ ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
+ &ipv6_hdr(skb)->daddr,
+ skb->len - off,
+ IPPROTO_UDP, 0);
+ break;
+ default:
+ goto out;
+ }
+
+ err = 0;
+
+out:
+ return err;
+}
+
+/**
+ * skb_checksum_setup - set up partial checksum offset
+ * @skb: the skb to set up
+ * @recalculate: if true the pseudo-header checksum will be recalculated
+ */
+int skb_checksum_setup(struct sk_buff *skb, bool recalculate)
+{
+ int err;
+
+ switch (skb->protocol) {
+ case htons(ETH_P_IP):
+ err = skb_checksum_setup_ip(skb, recalculate);
+ break;
+
+ case htons(ETH_P_IPV6):
+ err = skb_checksum_setup_ipv6(skb, recalculate);
+ break;
+
+ default:
+ err = -EPROTO;
+ break;
+ }
+
+ return err;
+}
+EXPORT_SYMBOL(skb_checksum_setup);
+
void __skb_warn_lro_forwarding(const struct sk_buff *skb)
{
net_warn_ratelimited("%s: received packets cannot be forwarded while LRO is enabled\n",
projects / ~andy / linux / blobdiff