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-rw-r--r--include/net/dst_metadata.h1
-rw-r--r--include/net/xfrm.h17
-rw-r--r--net/core/dst.c8
-rw-r--r--net/core/filter.c9
-rw-r--r--net/xfrm/Makefile6
-rw-r--r--net/xfrm/xfrm_interface_bpf.c115
-rw-r--r--net/xfrm/xfrm_interface_core.c14
7 files changed, 168 insertions, 2 deletions
diff --git a/include/net/dst_metadata.h b/include/net/dst_metadata.h
index a454cf4327fe..1b7fae4c6b24 100644
--- a/include/net/dst_metadata.h
+++ b/include/net/dst_metadata.h
@@ -26,6 +26,7 @@ struct macsec_info {
struct xfrm_md_info {
u32 if_id;
int link;
+ struct dst_entry *dst_orig;
};
struct metadata_dst {
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index e0cc6791c001..3707e6b34e67 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -2086,4 +2086,21 @@ static inline bool xfrm6_local_dontfrag(const struct sock *sk)
return false;
}
#endif
+
+#if (IS_BUILTIN(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) || \
+ (IS_MODULE(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES))
+
+extern struct metadata_dst __percpu *xfrm_bpf_md_dst;
+
+int register_xfrm_interface_bpf(void);
+
+#else
+
+static inline int register_xfrm_interface_bpf(void)
+{
+ return 0;
+}
+
+#endif
+
#endif /* _NET_XFRM_H */
diff --git a/net/core/dst.c b/net/core/dst.c
index bc9c9be4e080..bb14a0392388 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -316,6 +316,8 @@ void metadata_dst_free(struct metadata_dst *md_dst)
if (md_dst->type == METADATA_IP_TUNNEL)
dst_cache_destroy(&md_dst->u.tun_info.dst_cache);
#endif
+ if (md_dst->type == METADATA_XFRM)
+ dst_release(md_dst->u.xfrm_info.dst_orig);
kfree(md_dst);
}
EXPORT_SYMBOL_GPL(metadata_dst_free);
@@ -340,16 +342,18 @@ EXPORT_SYMBOL_GPL(metadata_dst_alloc_percpu);
void metadata_dst_free_percpu(struct metadata_dst __percpu *md_dst)
{
-#ifdef CONFIG_DST_CACHE
int cpu;
for_each_possible_cpu(cpu) {
struct metadata_dst *one_md_dst = per_cpu_ptr(md_dst, cpu);
+#ifdef CONFIG_DST_CACHE
if (one_md_dst->type == METADATA_IP_TUNNEL)
dst_cache_destroy(&one_md_dst->u.tun_info.dst_cache);
- }
#endif
+ if (one_md_dst->type == METADATA_XFRM)
+ dst_release(one_md_dst->u.xfrm_info.dst_orig);
+ }
free_percpu(md_dst);
}
EXPORT_SYMBOL_GPL(metadata_dst_free_percpu);
diff --git a/net/core/filter.c b/net/core/filter.c
index 8607136b6e2c..929358677183 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5631,6 +5631,15 @@ static const struct bpf_func_proto bpf_bind_proto = {
};
#ifdef CONFIG_XFRM
+
+#if (IS_BUILTIN(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) || \
+ (IS_MODULE(CONFIG_XFRM_INTERFACE) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES))
+
+struct metadata_dst __percpu *xfrm_bpf_md_dst;
+EXPORT_SYMBOL_GPL(xfrm_bpf_md_dst);
+
+#endif
+
BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
struct bpf_xfrm_state *, to, u32, size, u64, flags)
{
diff --git a/net/xfrm/Makefile b/net/xfrm/Makefile
index 08a2870fdd36..cd47f88921f5 100644
--- a/net/xfrm/Makefile
+++ b/net/xfrm/Makefile
@@ -5,6 +5,12 @@
xfrm_interface-$(CONFIG_XFRM_INTERFACE) += xfrm_interface_core.o
+ifeq ($(CONFIG_XFRM_INTERFACE),m)
+xfrm_interface-$(CONFIG_DEBUG_INFO_BTF_MODULES) += xfrm_interface_bpf.o
+else ifeq ($(CONFIG_XFRM_INTERFACE),y)
+xfrm_interface-$(CONFIG_DEBUG_INFO_BTF) += xfrm_interface_bpf.o
+endif
+
obj-$(CONFIG_XFRM) := xfrm_policy.o xfrm_state.o xfrm_hash.o \
xfrm_input.o xfrm_output.o \
xfrm_sysctl.o xfrm_replay.o xfrm_device.o
diff --git a/net/xfrm/xfrm_interface_bpf.c b/net/xfrm/xfrm_interface_bpf.c
new file mode 100644
index 000000000000..1ef2162cebcf
--- /dev/null
+++ b/net/xfrm/xfrm_interface_bpf.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Unstable XFRM Helpers for TC-BPF hook
+ *
+ * These are called from SCHED_CLS BPF programs. Note that it is
+ * allowed to break compatibility for these functions since the interface they
+ * are exposed through to BPF programs is explicitly unstable.
+ */
+
+#include <linux/bpf.h>
+#include <linux/btf_ids.h>
+
+#include <net/dst_metadata.h>
+#include <net/xfrm.h>
+
+/* bpf_xfrm_info - XFRM metadata information
+ *
+ * Members:
+ * @if_id - XFRM if_id:
+ * Transmit: if_id to be used in policy and state lookups
+ * Receive: if_id of the state matched for the incoming packet
+ * @link - Underlying device ifindex:
+ * Transmit: used as the underlying device in VRF routing
+ * Receive: the device on which the packet had been received
+ */
+struct bpf_xfrm_info {
+ u32 if_id;
+ int link;
+};
+
+__diag_push();
+__diag_ignore_all("-Wmissing-prototypes",
+ "Global functions as their definitions will be in xfrm_interface BTF");
+
+/* bpf_skb_get_xfrm_info - Get XFRM metadata
+ *
+ * Parameters:
+ * @skb_ctx - Pointer to ctx (__sk_buff) in TC program
+ * Cannot be NULL
+ * @to - Pointer to memory to which the metadata will be copied
+ * Cannot be NULL
+ */
+__used noinline
+int bpf_skb_get_xfrm_info(struct __sk_buff *skb_ctx, struct bpf_xfrm_info *to)
+{
+ struct sk_buff *skb = (struct sk_buff *)skb_ctx;
+ struct xfrm_md_info *info;
+
+ info = skb_xfrm_md_info(skb);
+ if (!info)
+ return -EINVAL;
+
+ to->if_id = info->if_id;
+ to->link = info->link;
+ return 0;
+}
+
+/* bpf_skb_get_xfrm_info - Set XFRM metadata
+ *
+ * Parameters:
+ * @skb_ctx - Pointer to ctx (__sk_buff) in TC program
+ * Cannot be NULL
+ * @from - Pointer to memory from which the metadata will be copied
+ * Cannot be NULL
+ */
+__used noinline
+int bpf_skb_set_xfrm_info(struct __sk_buff *skb_ctx,
+ const struct bpf_xfrm_info *from)
+{
+ struct sk_buff *skb = (struct sk_buff *)skb_ctx;
+ struct metadata_dst *md_dst;
+ struct xfrm_md_info *info;
+
+ if (unlikely(skb_metadata_dst(skb)))
+ return -EINVAL;
+
+ if (!xfrm_bpf_md_dst) {
+ struct metadata_dst __percpu *tmp;
+
+ tmp = metadata_dst_alloc_percpu(0, METADATA_XFRM, GFP_ATOMIC);
+ if (!tmp)
+ return -ENOMEM;
+ if (cmpxchg(&xfrm_bpf_md_dst, NULL, tmp))
+ metadata_dst_free_percpu(tmp);
+ }
+ md_dst = this_cpu_ptr(xfrm_bpf_md_dst);
+
+ info = &md_dst->u.xfrm_info;
+
+ info->if_id = from->if_id;
+ info->link = from->link;
+ skb_dst_force(skb);
+ info->dst_orig = skb_dst(skb);
+
+ dst_hold((struct dst_entry *)md_dst);
+ skb_dst_set(skb, (struct dst_entry *)md_dst);
+ return 0;
+}
+
+__diag_pop()
+
+BTF_SET8_START(xfrm_ifc_kfunc_set)
+BTF_ID_FLAGS(func, bpf_skb_get_xfrm_info)
+BTF_ID_FLAGS(func, bpf_skb_set_xfrm_info)
+BTF_SET8_END(xfrm_ifc_kfunc_set)
+
+static const struct btf_kfunc_id_set xfrm_interface_kfunc_set = {
+ .owner = THIS_MODULE,
+ .set = &xfrm_ifc_kfunc_set,
+};
+
+int __init register_xfrm_interface_bpf(void)
+{
+ return register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS,
+ &xfrm_interface_kfunc_set);
+}
diff --git a/net/xfrm/xfrm_interface_core.c b/net/xfrm/xfrm_interface_core.c
index 5a67b120c4db..1f99dc469027 100644
--- a/net/xfrm/xfrm_interface_core.c
+++ b/net/xfrm/xfrm_interface_core.c
@@ -396,6 +396,14 @@ xfrmi_xmit2(struct sk_buff *skb, struct net_device *dev, struct flowi *fl)
if_id = md_info->if_id;
fl->flowi_oif = md_info->link;
+ if (md_info->dst_orig) {
+ struct dst_entry *tmp_dst = dst;
+
+ dst = md_info->dst_orig;
+ skb_dst_set(skb, dst);
+ md_info->dst_orig = NULL;
+ dst_release(tmp_dst);
+ }
} else {
if_id = xi->p.if_id;
}
@@ -1162,12 +1170,18 @@ static int __init xfrmi_init(void)
if (err < 0)
goto rtnl_link_failed;
+ err = register_xfrm_interface_bpf();
+ if (err < 0)
+ goto kfunc_failed;
+
lwtunnel_encap_add_ops(&xfrmi_encap_ops, LWTUNNEL_ENCAP_XFRM);
xfrm_if_register_cb(&xfrm_if_cb);
return err;
+kfunc_failed:
+ rtnl_link_unregister(&xfrmi_link_ops);
rtnl_link_failed:
xfrmi6_fini();
xfrmi6_failed: