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-rw-r--r--net/ipv6/ila/ila_common.c155
1 files changed, 155 insertions, 0 deletions
diff --git a/net/ipv6/ila/ila_common.c b/net/ipv6/ila/ila_common.c
new file mode 100644
index 000000000..95e914691
--- /dev/null
+++ b/net/ipv6/ila/ila_common.c
@@ -0,0 +1,155 @@
+#include <linux/errno.h>
+#include <linux/ip.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/socket.h>
+#include <linux/types.h>
+#include <net/checksum.h>
+#include <net/ip.h>
+#include <net/ip6_fib.h>
+#include <net/lwtunnel.h>
+#include <net/protocol.h>
+#include <uapi/linux/ila.h>
+#include "ila.h"
+
+void ila_init_saved_csum(struct ila_params *p)
+{
+ if (!p->locator_match.v64)
+ return;
+
+ p->csum_diff = compute_csum_diff8(
+ (__be32 *)&p->locator,
+ (__be32 *)&p->locator_match);
+}
+
+static __wsum get_csum_diff_iaddr(struct ila_addr *iaddr, struct ila_params *p)
+{
+ if (p->locator_match.v64)
+ return p->csum_diff;
+ else
+ return compute_csum_diff8((__be32 *)&p->locator,
+ (__be32 *)&iaddr->loc);
+}
+
+static __wsum get_csum_diff(struct ipv6hdr *ip6h, struct ila_params *p)
+{
+ return get_csum_diff_iaddr(ila_a2i(&ip6h->daddr), p);
+}
+
+static void ila_csum_do_neutral_fmt(struct ila_addr *iaddr,
+ struct ila_params *p)
+{
+ __sum16 *adjust = (__force __sum16 *)&iaddr->ident.v16[3];
+ __wsum diff, fval;
+
+ diff = get_csum_diff_iaddr(iaddr, p);
+
+ fval = (__force __wsum)(ila_csum_neutral_set(iaddr->ident) ?
+ CSUM_NEUTRAL_FLAG : ~CSUM_NEUTRAL_FLAG);
+
+ diff = csum_add(diff, fval);
+
+ *adjust = ~csum_fold(csum_add(diff, csum_unfold(*adjust)));
+
+ /* Flip the csum-neutral bit. Either we are doing a SIR->ILA
+ * translation with ILA_CSUM_NEUTRAL_MAP as the csum_method
+ * and the C-bit is not set, or we are doing an ILA-SIR
+ * tranlsation and the C-bit is set.
+ */
+ iaddr->ident.csum_neutral ^= 1;
+}
+
+static void ila_csum_do_neutral_nofmt(struct ila_addr *iaddr,
+ struct ila_params *p)
+{
+ __sum16 *adjust = (__force __sum16 *)&iaddr->ident.v16[3];
+ __wsum diff;
+
+ diff = get_csum_diff_iaddr(iaddr, p);
+
+ *adjust = ~csum_fold(csum_add(diff, csum_unfold(*adjust)));
+}
+
+static void ila_csum_adjust_transport(struct sk_buff *skb,
+ struct ila_params *p)
+{
+ size_t nhoff = sizeof(struct ipv6hdr);
+ struct ipv6hdr *ip6h = ipv6_hdr(skb);
+ __wsum diff;
+
+ switch (ip6h->nexthdr) {
+ case NEXTHDR_TCP:
+ if (likely(pskb_may_pull(skb, nhoff + sizeof(struct tcphdr)))) {
+ struct tcphdr *th = (struct tcphdr *)
+ (skb_network_header(skb) + nhoff);
+
+ diff = get_csum_diff(ip6h, p);
+ inet_proto_csum_replace_by_diff(&th->check, skb,
+ diff, true);
+ }
+ break;
+ case NEXTHDR_UDP:
+ if (likely(pskb_may_pull(skb, nhoff + sizeof(struct udphdr)))) {
+ struct udphdr *uh = (struct udphdr *)
+ (skb_network_header(skb) + nhoff);
+
+ if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
+ diff = get_csum_diff(ip6h, p);
+ inet_proto_csum_replace_by_diff(&uh->check, skb,
+ diff, true);
+ if (!uh->check)
+ uh->check = CSUM_MANGLED_0;
+ }
+ }
+ break;
+ case NEXTHDR_ICMP:
+ if (likely(pskb_may_pull(skb,
+ nhoff + sizeof(struct icmp6hdr)))) {
+ struct icmp6hdr *ih = (struct icmp6hdr *)
+ (skb_network_header(skb) + nhoff);
+
+ diff = get_csum_diff(ip6h, p);
+ inet_proto_csum_replace_by_diff(&ih->icmp6_cksum, skb,
+ diff, true);
+ }
+ break;
+ }
+}
+
+void ila_update_ipv6_locator(struct sk_buff *skb, struct ila_params *p,
+ bool sir2ila)
+{
+ struct ipv6hdr *ip6h = ipv6_hdr(skb);
+ struct ila_addr *iaddr = ila_a2i(&ip6h->daddr);
+
+ switch (p->csum_mode) {
+ case ILA_CSUM_ADJUST_TRANSPORT:
+ ila_csum_adjust_transport(skb, p);
+ break;
+ case ILA_CSUM_NEUTRAL_MAP:
+ if (sir2ila) {
+ if (WARN_ON(ila_csum_neutral_set(iaddr->ident))) {
+ /* Checksum flag should never be
+ * set in a formatted SIR address.
+ */
+ break;
+ }
+ } else if (!ila_csum_neutral_set(iaddr->ident)) {
+ /* ILA to SIR translation and C-bit isn't
+ * set so we're good.
+ */
+ break;
+ }
+ ila_csum_do_neutral_fmt(iaddr, p);
+ break;
+ case ILA_CSUM_NEUTRAL_MAP_AUTO:
+ ila_csum_do_neutral_nofmt(iaddr, p);
+ break;
+ case ILA_CSUM_NO_ACTION:
+ break;
+ }
+
+ /* Now change destination address */
+ iaddr->loc = p->locator;
+}