commit 8d3bde79494004524e8bb80bcb96ce742b3b878a
author Maciej Żenczykowski <maze@google.com> Sun Oct 08 18:43:23 2023 -0700
committer Maciej Żenczykowski <maze@google.com> Sun Oct 08 20:16:59 2023 -0700
tree c9c7e17593f46a7141e1b57bdc9e94b51019bb20
parent a8852b24885988dd92f3518e7364193c0405b88a

type safety for is_ethernet

(reversing logic, as 'rawip.rawip' is much shorter then 'ethernet.ethernet')

Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: Ib48cc2b889e8b587e14edbe89606f887a884af87

bpf_progs/offload.c

diff --git a/bpf_progs/offload.c b/bpf_progs/offload.c
index 0aab777..3682ac5 100644
--- a/bpf_progs/offload.c
+++ b/bpf_progs/offload.c
@@ -124,8 +124,12 @@
 DEFINE_BPF_MAP_GRW(tether_upstream6_map, HASH, TetherUpstream6Key, Tether6Value, 64,
                    TETHERING_GID)
 
-static inline __always_inline int do_forward6(struct __sk_buff* skb, const bool is_ethernet,
-        const bool downstream, const struct kver_uint kver) {
+static inline __always_inline int do_forward6(struct __sk_buff* skb,
+                                              const struct rawip_bool rawip,
+                                              const bool downstream,
+                                              const struct kver_uint kver) {
+    const bool is_ethernet = !rawip.rawip;
+
     // Must be meta-ethernet IPv6 frame
     if (skb->protocol != htons(ETH_P_IPV6)) return TC_ACT_PIPE;
 
@@ -356,9 +360,10 @@
 
 static inline __always_inline int do_forward4_bottom(struct __sk_buff* skb,
         const int l2_header_size, void* data, const void* data_end,
-        struct ethhdr* eth, struct iphdr* ip, const bool is_ethernet,
+        struct ethhdr* eth, struct iphdr* ip, const struct rawip_bool rawip,
         const bool downstream, const bool updatetime, const bool is_tcp,
         const struct kver_uint kver) {
+    const bool is_ethernet = !rawip.rawip;
     struct tcphdr* tcph = is_tcp ? (void*)(ip + 1) : NULL;
     struct udphdr* udph = is_tcp ? NULL : (void*)(ip + 1);
 
@@ -547,8 +552,13 @@
     return bpf_redirect(v->oif, 0 /* this is effectively BPF_F_EGRESS */);
 }
 
-static inline __always_inline int do_forward4(struct __sk_buff* skb, const bool is_ethernet,
-        const bool downstream, const bool updatetime, const struct kver_uint kver) {
+static inline __always_inline int do_forward4(struct __sk_buff* skb,
+                                              const struct rawip_bool rawip,
+                                              const bool downstream,
+                                              const bool updatetime,
+                                              const struct kver_uint kver) {
+    const bool is_ethernet = !rawip.rawip;
+
     // Require ethernet dst mac address to be our unicast address.
     if (is_ethernet && (skb->pkt_type != PACKET_HOST)) return TC_ACT_PIPE;
 
@@ -636,10 +646,10 @@
     // if the underlying requisite kernel support (bpf_ktime_get_boot_ns) was backported.
     if (is_tcp) {
       return do_forward4_bottom(skb, l2_header_size, data, data_end, eth, ip,
-                                is_ethernet, downstream, updatetime, /* is_tcp */ true, kver);
+                                rawip, downstream, updatetime, /* is_tcp */ true, kver);
     } else {
       return do_forward4_bottom(skb, l2_header_size, data, data_end, eth, ip,
-                                is_ethernet, downstream, updatetime, /* is_tcp */ false, kver);
+                                rawip, downstream, updatetime, /* is_tcp */ false, kver);
     }
 }
 
@@ -797,12 +807,12 @@
 
 DEFINE_BPF_MAP_GRW(tether_dev_map, DEVMAP_HASH, uint32_t, uint32_t, 64, TETHERING_GID)
 
-static inline __always_inline int do_xdp_forward6(struct xdp_md *ctx, const bool is_ethernet,
+static inline __always_inline int do_xdp_forward6(struct xdp_md *ctx, const struct rawip_bool rawip,
         const bool downstream) {
     return XDP_PASS;
 }
 
-static inline __always_inline int do_xdp_forward4(struct xdp_md *ctx, const bool is_ethernet,
+static inline __always_inline int do_xdp_forward4(struct xdp_md *ctx, const struct rawip_bool rawip,
         const bool downstream) {
     return XDP_PASS;
 }