Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking updates from David Miller:

 1) Add Maglev hashing scheduler to IPVS, from Inju Song.

 2) Lots of new TC subsystem tests from Roman Mashak.

 3) Add TCP zero copy receive and fix delayed acks and autotuning with
    SO_RCVLOWAT, from Eric Dumazet.

 4) Add XDP_REDIRECT support to mlx5 driver, from Jesper Dangaard
    Brouer.

 5) Add ttl inherit support to vxlan, from Hangbin Liu.

 6) Properly separate ipv6 routes into their logically independant
    components. fib6_info for the routing table, and fib6_nh for sets of
    nexthops, which thus can be shared. From David Ahern.

 7) Add bpf_xdp_adjust_tail helper, which can be used to generate ICMP
    messages from XDP programs. From Nikita V. Shirokov.

 8) Lots of long overdue cleanups to the r8169 driver, from Heiner
    Kallweit.

 9) Add BTF ("BPF Type Format"), from Martin KaFai Lau.

10) Add traffic condition monitoring to iwlwifi, from Luca Coelho.

11) Plumb extack down into fib_rules, from Roopa Prabhu.

12) Add Flower classifier offload support to igb, from Vinicius Costa
    Gomes.

13) Add UDP GSO support, from Willem de Bruijn.

14) Add documentation for eBPF helpers, from Quentin Monnet.

15) Add TLS tx offload to mlx5, from Ilya Lesokhin.

16) Allow applications to be given the number of bytes available to read
    on a socket via a control message returned from recvmsg(), from
    Soheil Hassas Yeganeh.

17) Add x86_32 eBPF JIT compiler, from Wang YanQing.

18) Add AF_XDP sockets, with zerocopy support infrastructure as well.
    From Björn Töpel.

19) Remove indirect load support from all of the BPF JITs and handle
    these operations in the verifier by translating them into native BPF
    instead. From Daniel Borkmann.

20) Add GRO support to ipv6 gre tunnels, from Eran Ben Elisha.

21) Allow XDP programs to do lookups in the main kernel routing tables
    for forwarding. From David Ahern.

22) Allow drivers to store hardware state into an ELF section of kernel
    dump vmcore files, and use it in cxgb4. From Rahul Lakkireddy.

23) Various RACK and loss detection improvements in TCP, from Yuchung
    Cheng.

24) Add TCP SACK compression, from Eric Dumazet.

25) Add User Mode Helper support and basic bpfilter infrastructure, from
    Alexei Starovoitov.

26) Support ports and protocol values in RTM_GETROUTE, from Roopa
    Prabhu.

27) Support bulking in ->ndo_xdp_xmit() API, from Jesper Dangaard
    Brouer.

28) Add lots of forwarding selftests, from Petr Machata.

29) Add generic network device failover driver, from Sridhar Samudrala.

* ra.kernel.org:/pub/scm/linux/kernel/git/davem/net-next: (1959 commits)
  strparser: Add __strp_unpause and use it in ktls.
  rxrpc: Fix terminal retransmission connection ID to include the channel
  net: hns3: Optimize PF CMDQ interrupt switching process
  net: hns3: Fix for VF mailbox receiving unknown message
  net: hns3: Fix for VF mailbox cannot receiving PF response
  bnx2x: use the right constant
  Revert "net: sched: cls: Fix offloading when ingress dev is vxlan"
  net: dsa: b53: Fix for brcm tag issue in Cygnus SoC
  enic: fix UDP rss bits
  netdev-FAQ: clarify DaveM's position for stable backports
  rtnetlink: validate attributes in do_setlink()
  mlxsw: Add extack messages for port_{un, }split failures
  netdevsim: Add extack error message for devlink reload
  devlink: Add extack to reload and port_{un, }split operations
  net: metrics: add proper netlink validation
  ipmr: fix error path when ipmr_new_table fails
  ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds
  net: hns3: remove unused hclgevf_cfg_func_mta_filter
  netfilter: provide udp*_lib_lookup for nf_tproxy
  qed*: Utilize FW 8.37.2.0
  ...

9 files changed, 2399 insertions, 384 deletions

diff --git a/tools/include/linux/filter.h b/tools/include/linux/filter.h
index c5e512da8d8a..af55acf73e75 100644
--- a/tools/include/linux/filter.h
+++ b/tools/include/linux/filter.h
@@ -263,6 +263,16 @@
 #define BPF_LD_MAP_FD(DST, MAP_FD)				\
 	BPF_LD_IMM64_RAW(DST, BPF_PSEUDO_MAP_FD, MAP_FD)
 
+/* Relative call */
+
+#define BPF_CALL_REL(TGT)					\
+	((struct bpf_insn) {					\
+		.code  = BPF_JMP | BPF_CALL,			\
+		.dst_reg = 0,					\
+		.src_reg = BPF_PSEUDO_CALL,			\
+		.off   = 0,					\
+		.imm   = TGT })
+
 /* Program exit */
 
 #define BPF_EXIT_INSN()						\
diff --git a/tools/include/uapi/asm/bitsperlong.h b/tools/include/uapi/asm/bitsperlong.h
new file mode 100644
index 000000000000..8dd6aefdafa4
--- /dev/null
+++ b/tools/include/uapi/asm/bitsperlong.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#if defined(__i386__) || defined(__x86_64__)
+#include "../../arch/x86/include/uapi/asm/bitsperlong.h"
+#elif defined(__aarch64__)
+#include "../../arch/arm64/include/uapi/asm/bitsperlong.h"
+#elif defined(__powerpc__)
+#include "../../arch/powerpc/include/uapi/asm/bitsperlong.h"
+#elif defined(__s390__)
+#include "../../arch/s390/include/uapi/asm/bitsperlong.h"
+#elif defined(__sparc__)
+#include "../../arch/sparc/include/uapi/asm/bitsperlong.h"
+#elif defined(__mips__)
+#include "../../arch/mips/include/uapi/asm/bitsperlong.h"
+#elif defined(__ia64__)
+#include "../../arch/ia64/include/uapi/asm/bitsperlong.h"
+#else
+#include <asm-generic/bitsperlong.h>
+#endif
diff --git a/tools/include/uapi/asm/errno.h b/tools/include/uapi/asm/errno.h
new file mode 100644
index 000000000000..ce3c5945a1c4
--- /dev/null
+++ b/tools/include/uapi/asm/errno.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#if defined(__i386__) || defined(__x86_64__)
+#include "../../arch/x86/include/uapi/asm/errno.h"
+#elif defined(__powerpc__)
+#include "../../arch/powerpc/include/uapi/asm/errno.h"
+#elif defined(__sparc__)
+#include "../../arch/sparc/include/uapi/asm/errno.h"
+#elif defined(__alpha__)
+#include "../../arch/alpha/include/uapi/asm/errno.h"
+#elif defined(__mips__)
+#include "../../arch/mips/include/uapi/asm/errno.h"
+#elif defined(__ia64__)
+#include "../../arch/ia64/include/uapi/asm/errno.h"
+#elif defined(__xtensa__)
+#include "../../arch/xtensa/include/uapi/asm/errno.h"
+#else
+#include <asm-generic/errno.h>
+#endif
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 8c317737ba3f..e0b06784f227 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -95,6 +95,9 @@ enum bpf_cmd {
 	BPF_OBJ_GET_INFO_BY_FD,
 	BPF_PROG_QUERY,
 	BPF_RAW_TRACEPOINT_OPEN,
+	BPF_BTF_LOAD,
+	BPF_BTF_GET_FD_BY_ID,
+	BPF_TASK_FD_QUERY,
 };
 
 enum bpf_map_type {
@@ -115,6 +118,8 @@ enum bpf_map_type {
 	BPF_MAP_TYPE_DEVMAP,
 	BPF_MAP_TYPE_SOCKMAP,
 	BPF_MAP_TYPE_CPUMAP,
+	BPF_MAP_TYPE_XSKMAP,
+	BPF_MAP_TYPE_SOCKHASH,
 };
 
 enum bpf_prog_type {
@@ -137,6 +142,8 @@ enum bpf_prog_type {
 	BPF_PROG_TYPE_SK_MSG,
 	BPF_PROG_TYPE_RAW_TRACEPOINT,
 	BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
+	BPF_PROG_TYPE_LWT_SEG6LOCAL,
+	BPF_PROG_TYPE_LIRC_MODE2,
 };
 
 enum bpf_attach_type {
@@ -154,6 +161,9 @@ enum bpf_attach_type {
 	BPF_CGROUP_INET6_CONNECT,
 	BPF_CGROUP_INET4_POST_BIND,
 	BPF_CGROUP_INET6_POST_BIND,
+	BPF_CGROUP_UDP4_SENDMSG,
+	BPF_CGROUP_UDP6_SENDMSG,
+	BPF_LIRC_MODE2,
 	__MAX_BPF_ATTACH_TYPE
 };
 
@@ -279,6 +289,9 @@ union bpf_attr {
 					 */
 		char	map_name[BPF_OBJ_NAME_LEN];
 		__u32	map_ifindex;	/* ifindex of netdev to create on */
+		__u32	btf_fd;		/* fd pointing to a BTF type data */
+		__u32	btf_key_type_id;	/* BTF type_id of the key */
+		__u32	btf_value_type_id;	/* BTF type_id of the value */
 	};
 
 	struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */
@@ -339,6 +352,7 @@ union bpf_attr {
 			__u32		start_id;
 			__u32		prog_id;
 			__u32		map_id;
+			__u32		btf_id;
 		};
 		__u32		next_id;
 		__u32		open_flags;
@@ -363,398 +377,1704 @@ union bpf_attr {
 		__u64 name;
 		__u32 prog_fd;
 	} raw_tracepoint;
+
+	struct { /* anonymous struct for BPF_BTF_LOAD */
+		__aligned_u64	btf;
+		__aligned_u64	btf_log_buf;
+		__u32		btf_size;
+		__u32		btf_log_size;
+		__u32		btf_log_level;
+	};
+
+	struct {
+		__u32		pid;		/* input: pid */
+		__u32		fd;		/* input: fd */
+		__u32		flags;		/* input: flags */
+		__u32		buf_len;	/* input/output: buf len */
+		__aligned_u64	buf;		/* input/output:
+						 *   tp_name for tracepoint
+						 *   symbol for kprobe
+						 *   filename for uprobe
+						 */
+		__u32		prog_id;	/* output: prod_id */
+		__u32		fd_type;	/* output: BPF_FD_TYPE_* */
+		__u64		probe_offset;	/* output: probe_offset */
+		__u64		probe_addr;	/* output: probe_addr */
+	} task_fd_query;
 } __attribute__((aligned(8)));
 
-/* BPF helper function descriptions:
- *
- * void *bpf_map_lookup_elem(&map, &key)
- *     Return: Map value or NULL
- *
- * int bpf_map_update_elem(&map, &key, &value, flags)
- *     Return: 0 on success or negative error
- *
- * int bpf_map_delete_elem(&map, &key)
- *     Return: 0 on success or negative error
- *
- * int bpf_probe_read(void *dst, int size, void *src)
- *     Return: 0 on success or negative error
+/* The description below is an attempt at providing documentation to eBPF
+ * developers about the multiple available eBPF helper functions. It can be
+ * parsed and used to produce a manual page. The workflow is the following,
+ * and requires the rst2man utility:
+ *
+ *     $ ./scripts/bpf_helpers_doc.py \
+ *             --filename include/uapi/linux/bpf.h > /tmp/bpf-helpers.rst
+ *     $ rst2man /tmp/bpf-helpers.rst > /tmp/bpf-helpers.7
+ *     $ man /tmp/bpf-helpers.7
+ *
+ * Note that in order to produce this external documentation, some RST
+ * formatting is used in the descriptions to get "bold" and "italics" in
+ * manual pages. Also note that the few trailing white spaces are
+ * intentional, removing them would break paragraphs for rst2man.
+ *
+ * Start of BPF helper function descriptions:
+ *
+ * void *bpf_map_lookup_elem(struct bpf_map *map, const void *key)
+ * 	Description
+ * 		Perform a lookup in *map* for an entry associated to *key*.
+ * 	Return
+ * 		Map value associated to *key*, or **NULL** if no entry was
+ * 		found.
+ *
+ * int bpf_map_update_elem(struct bpf_map *map, const void *key, const void *value, u64 flags)
+ * 	Description
+ * 		Add or update the value of the entry associated to *key* in
+ * 		*map* with *value*. *flags* is one of:
+ *
+ * 		**BPF_NOEXIST**
+ * 			The entry for *key* must not exist in the map.
+ * 		**BPF_EXIST**
+ * 			The entry for *key* must already exist in the map.
+ * 		**BPF_ANY**
+ * 			No condition on the existence of the entry for *key*.
+ *
+ * 		Flag value **BPF_NOEXIST** cannot be used for maps of types
+ * 		**BPF_MAP_TYPE_ARRAY** or **BPF_MAP_TYPE_PERCPU_ARRAY**  (all
+ * 		elements always exist), the helper would return an error.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_map_delete_elem(struct bpf_map *map, const void *key)
+ * 	Description
+ * 		Delete entry with *key* from *map*.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_probe_read(void *dst, u32 size, const void *src)
+ * 	Description
+ * 		For tracing programs, safely attempt to read *size* bytes from
+ * 		address *src* and store the data in *dst*.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  *
  * u64 bpf_ktime_get_ns(void)
- *     Return: current ktime
- *
- * int bpf_trace_printk(const char *fmt, int fmt_size, ...)
- *     Return: length of buffer written or negative error
- *
- * u32 bpf_prandom_u32(void)
- *     Return: random value
- *
- * u32 bpf_raw_smp_processor_id(void)
- *     Return: SMP processor ID
- *
- * int bpf_skb_store_bytes(skb, offset, from, len, flags)
- *     store bytes into packet
- *     @skb: pointer to skb
- *     @offset: offset within packet from skb->mac_header
- *     @from: pointer where to copy bytes from
- *     @len: number of bytes to store into packet
- *     @flags: bit 0 - if true, recompute skb->csum
- *             other bits - reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_l3_csum_replace(skb, offset, from, to, flags)
- *     recompute IP checksum
- *     @skb: pointer to skb
- *     @offset: offset within packet where IP checksum is located
- *     @from: old value of header field
- *     @to: new value of header field
- *     @flags: bits 0-3 - size of header field
- *             other bits - reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_l4_csum_replace(skb, offset, from, to, flags)
- *     recompute TCP/UDP checksum
- *     @skb: pointer to skb
- *     @offset: offset within packet where TCP/UDP checksum is located
- *     @from: old value of header field
- *     @to: new value of header field
- *     @flags: bits 0-3 - size of header field
- *             bit 4 - is pseudo header
- *             other bits - reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_tail_call(ctx, prog_array_map, index)
- *     jump into another BPF program
- *     @ctx: context pointer passed to next program
- *     @prog_array_map: pointer to map which type is BPF_MAP_TYPE_PROG_ARRAY
- *     @index: 32-bit index inside array that selects specific program to run
- *     Return: 0 on success or negative error
- *
- * int bpf_clone_redirect(skb, ifindex, flags)
- *     redirect to another netdev
- *     @skb: pointer to skb
- *     @ifindex: ifindex of the net device
- *     @flags: bit 0 - if set, redirect to ingress instead of egress
- *             other bits - reserved
- *     Return: 0 on success or negative error
+ * 	Description
+ * 		Return the time elapsed since system boot, in nanoseconds.
+ * 	Return
+ * 		Current *ktime*.
+ *
+ * int bpf_trace_printk(const char *fmt, u32 fmt_size, ...)
+ * 	Description
+ * 		This helper is a "printk()-like" facility for debugging. It
+ * 		prints a message defined by format *fmt* (of size *fmt_size*)
+ * 		to file *\/sys/kernel/debug/tracing/trace* from DebugFS, if
+ * 		available. It can take up to three additional **u64**
+ * 		arguments (as an eBPF helpers, the total number of arguments is
+ * 		limited to five).
+ *
+ * 		Each time the helper is called, it appends a line to the trace.
+ * 		The format of the trace is customizable, and the exact output
+ * 		one will get depends on the options set in
+ * 		*\/sys/kernel/debug/tracing/trace_options* (see also the
+ * 		*README* file under the same directory). However, it usually
+ * 		defaults to something like:
+ *
+ * 		::
+ *
+ * 			telnet-470   [001] .N.. 419421.045894: 0x00000001: <formatted msg>
+ *
+ * 		In the above:
+ *
+ * 			* ``telnet`` is the name of the current task.
+ * 			* ``470`` is the PID of the current task.
+ * 			* ``001`` is the CPU number on which the task is
+ * 			  running.
+ * 			* In ``.N..``, each character refers to a set of
+ * 			  options (whether irqs are enabled, scheduling
+ * 			  options, whether hard/softirqs are running, level of
+ * 			  preempt_disabled respectively). **N** means that
+ * 			  **TIF_NEED_RESCHED** and **PREEMPT_NEED_RESCHED**
+ * 			  are set.
+ * 			* ``419421.045894`` is a timestamp.
+ * 			* ``0x00000001`` is a fake value used by BPF for the
+ * 			  instruction pointer register.
+ * 			* ``<formatted msg>`` is the message formatted with
+ * 			  *fmt*.
+ *
+ * 		The conversion specifiers supported by *fmt* are similar, but
+ * 		more limited than for printk(). They are **%d**, **%i**,
+ * 		**%u**, **%x**, **%ld**, **%li**, **%lu**, **%lx**, **%lld**,
+ * 		**%lli**, **%llu**, **%llx**, **%p**, **%s**. No modifier (size
+ * 		of field, padding with zeroes, etc.) is available, and the
+ * 		helper will return **-EINVAL** (but print nothing) if it
+ * 		encounters an unknown specifier.
+ *
+ * 		Also, note that **bpf_trace_printk**\ () is slow, and should
+ * 		only be used for debugging purposes. For this reason, a notice
+ * 		bloc (spanning several lines) is printed to kernel logs and
+ * 		states that the helper should not be used "for production use"
+ * 		the first time this helper is used (or more precisely, when
+ * 		**trace_printk**\ () buffers are allocated). For passing values
+ * 		to user space, perf events should be preferred.
+ * 	Return
+ * 		The number of bytes written to the buffer, or a negative error
+ * 		in case of failure.
+ *
+ * u32 bpf_get_prandom_u32(void)
+ * 	Description
+ * 		Get a pseudo-random number.
+ *
+ * 		From a security point of view, this helper uses its own
+ * 		pseudo-random internal state, and cannot be used to infer the
+ * 		seed of other random functions in the kernel. However, it is
+ * 		essential to note that the generator used by the helper is not
+ * 		cryptographically secure.
+ * 	Return
+ * 		A random 32-bit unsigned value.
+ *
+ * u32 bpf_get_smp_processor_id(void)
+ * 	Description
+ * 		Get the SMP (symmetric multiprocessing) processor id. Note that
+ * 		all programs run with preemption disabled, which means that the
+ * 		SMP processor id is stable during all the execution of the
+ * 		program.
+ * 	Return
+ * 		The SMP id of the processor running the program.
+ *
+ * int bpf_skb_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len, u64 flags)
+ * 	Description
+ * 		Store *len* bytes from address *from* into the packet
+ * 		associated to *skb*, at *offset*. *flags* are a combination of
+ * 		**BPF_F_RECOMPUTE_CSUM** (automatically recompute the
+ * 		checksum for the packet after storing the bytes) and
+ * 		**BPF_F_INVALIDATE_HASH** (set *skb*\ **->hash**, *skb*\
+ * 		**->swhash** and *skb*\ **->l4hash** to 0).
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_l3_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 size)
+ * 	Description
+ * 		Recompute the layer 3 (e.g. IP) checksum for the packet
+ * 		associated to *skb*. Computation is incremental, so the helper
+ * 		must know the former value of the header field that was
+ * 		modified (*from*), the new value of this field (*to*), and the
+ * 		number of bytes (2 or 4) for this field, stored in *size*.
+ * 		Alternatively, it is possible to store the difference between
+ * 		the previous and the new values of the header field in *to*, by
+ * 		setting *from* and *size* to 0. For both methods, *offset*
+ * 		indicates the location of the IP checksum within the packet.
+ *
+ * 		This helper works in combination with **bpf_csum_diff**\ (),
+ * 		which does not update the checksum in-place, but offers more
+ * 		flexibility and can handle sizes larger than 2 or 4 for the
+ * 		checksum to update.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_l4_csum_replace(struct sk_buff *skb, u32 offset, u64 from, u64 to, u64 flags)
+ * 	Description
+ * 		Recompute the layer 4 (e.g. TCP, UDP or ICMP) checksum for the
+ * 		packet associated to *skb*. Computation is incremental, so the
+ * 		helper must know the former value of the header field that was
+ * 		modified (*from*), the new value of this field (*to*), and the
+ * 		number of bytes (2 or 4) for this field, stored on the lowest
+ * 		four bits of *flags*. Alternatively, it is possible to store
+ * 		the difference between the previous and the new values of the
+ * 		header field in *to*, by setting *from* and the four lowest
+ * 		bits of *flags* to 0. For both methods, *offset* indicates the
+ * 		location of the IP checksum within the packet. In addition to
+ * 		the size of the field, *flags* can be added (bitwise OR) actual
+ * 		flags. With **BPF_F_MARK_MANGLED_0**, a null checksum is left
+ * 		untouched (unless **BPF_F_MARK_ENFORCE** is added as well), and
+ * 		for updates resulting in a null checksum the value is set to
+ * 		**CSUM_MANGLED_0** instead. Flag **BPF_F_PSEUDO_HDR** indicates
+ * 		the checksum is to be computed against a pseudo-header.
+ *
+ * 		This helper works in combination with **bpf_csum_diff**\ (),
+ * 		which does not update the checksum in-place, but offers more
+ * 		flexibility and can handle sizes larger than 2 or 4 for the
+ * 		checksum to update.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_tail_call(void *ctx, struct bpf_map *prog_array_map, u32 index)
+ * 	Description
+ * 		This special helper is used to trigger a "tail call", or in
+ * 		other words, to jump into another eBPF program. The same stack
+ * 		frame is used (but values on stack and in registers for the
+ * 		caller are not accessible to the callee). This mechanism allows
+ * 		for program chaining, either for raising the maximum number of
+ * 		available eBPF instructions, or to execute given programs in
+ * 		conditional blocks. For security reasons, there is an upper
+ * 		limit to the number of successive tail calls that can be
+ * 		performed.
+ *
+ * 		Upon call of this helper, the program attempts to jump into a
+ * 		program referenced at index *index* in *prog_array_map*, a
+ * 		special map of type **BPF_MAP_TYPE_PROG_ARRAY**, and passes
+ * 		*ctx*, a pointer to the context.
+ *
+ * 		If the call succeeds, the kernel immediately runs the first
+ * 		instruction of the new program. This is not a function call,
+ * 		and it never returns to the previous program. If the call
+ * 		fails, then the helper has no effect, and the caller continues
+ * 		to run its subsequent instructions. A call can fail if the
+ * 		destination program for the jump does not exist (i.e. *index*
+ * 		is superior to the number of entries in *prog_array_map*), or
+ * 		if the maximum number of tail calls has been reached for this
+ * 		chain of programs. This limit is defined in the kernel by the
+ * 		macro **MAX_TAIL_CALL_CNT** (not accessible to user space),
+ * 		which is currently set to 32.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_clone_redirect(struct sk_buff *skb, u32 ifindex, u64 flags)
+ * 	Description
+ * 		Clone and redirect the packet associated to *skb* to another
+ * 		net device of index *ifindex*. Both ingress and egress
+ * 		interfaces can be used for redirection. The **BPF_F_INGRESS**
+ * 		value in *flags* is used to make the distinction (ingress path
+ * 		is selected if the flag is present, egress path otherwise).
+ * 		This is the only flag supported for now.
+ *
+ * 		In comparison with **bpf_redirect**\ () helper,
+ * 		**bpf_clone_redirect**\ () has the associated cost of
+ * 		duplicating the packet buffer, but this can be executed out of
+ * 		the eBPF program. Conversely, **bpf_redirect**\ () is more
+ * 		efficient, but it is handled through an action code where the
+ * 		redirection happens only after the eBPF program has returned.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  *
  * u64 bpf_get_current_pid_tgid(void)
- *     Return: current->tgid << 32 | current->pid
+ * 	Return
+ * 		A 64-bit integer containing the current tgid and pid, and
+ * 		created as such:
+ * 		*current_task*\ **->tgid << 32 \|**
+ * 		*current_task*\ **->pid**.
  *
  * u64 bpf_get_current_uid_gid(void)
- *     Return: current_gid << 32 | current_uid
- *
- * int bpf_get_current_comm(char *buf, int size_of_buf)
- *     stores current->comm into buf
- *     Return: 0 on success or negative error
- *
- * u32 bpf_get_cgroup_classid(skb)
- *     retrieve a proc's classid
- *     @skb: pointer to skb
- *     Return: classid if != 0
- *
- * int bpf_skb_vlan_push(skb, vlan_proto, vlan_tci)
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_vlan_pop(skb)
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_get_tunnel_key(skb, key, size, flags)
- * int bpf_skb_set_tunnel_key(skb, key, size, flags)
- *     retrieve or populate tunnel metadata
- *     @skb: pointer to skb
- *     @key: pointer to 'struct bpf_tunnel_key'
- *     @size: size of 'struct bpf_tunnel_key'
- *     @flags: room for future extensions
- *     Return: 0 on success or negative error
- *
- * u64 bpf_perf_event_read(map, flags)
- *     read perf event counter value
- *     @map: pointer to perf_event_array map
- *     @flags: index of event in the map or bitmask flags
- *     Return: value of perf event counter read or error code
- *
- * int bpf_redirect(ifindex, flags)
- *     redirect to another netdev
- *     @ifindex: ifindex of the net device
- *     @flags:
- *	  cls_bpf:
- *          bit 0 - if set, redirect to ingress instead of egress
- *          other bits - reserved
- *	  xdp_bpf:
- *	    all bits - reserved
- *     Return: cls_bpf: TC_ACT_REDIRECT on success or TC_ACT_SHOT on error
- *	       xdp_bfp: XDP_REDIRECT on success or XDP_ABORT on error
- * int bpf_redirect_map(map, key, flags)
- *     redirect to endpoint in map
- *     @map: pointer to dev map
- *     @key: index in map to lookup
- *     @flags: --
- *     Return: XDP_REDIRECT on success or XDP_ABORT on error
- *
- * u32 bpf_get_route_realm(skb)
- *     retrieve a dst's tclassid
- *     @skb: pointer to skb
- *     Return: realm if != 0
- *
- * int bpf_perf_event_output(ctx, map, flags, data, size)
- *     output perf raw sample
- *     @ctx: struct pt_regs*
- *     @map: pointer to perf_event_array map
- *     @flags: index of event in the map or bitmask flags
- *     @data: data on stack to be output as raw data
- *     @size: size of data
- *     Return: 0 on success or negative error
- *
- * int bpf_get_stackid(ctx, map, flags)
- *     walk user or kernel stack and return id
- *     @ctx: struct pt_regs*
- *     @map: pointer to stack_trace map
- *     @flags: bits 0-7 - numer of stack frames to skip
- *             bit 8 - collect user stack instead of kernel
- *             bit 9 - compare stacks by hash only
- *             bit 10 - if two different stacks hash into the same stackid
- *                      discard old
- *             other bits - reserved
- *     Return: >= 0 stackid on success or negative error
- *
- * s64 bpf_csum_diff(from, from_size, to, to_size, seed)
- *     calculate csum diff
- *     @from: raw from buffer
- *     @from_size: length of from buffer
- *     @to: raw to buffer
- *     @to_size: length of to buffer
- *     @seed: optional seed
- *     Return: csum result or negative error code
- *
- * int bpf_skb_get_tunnel_opt(skb, opt, size)
- *     retrieve tunnel options metadata
- *     @skb: pointer to skb
- *     @opt: pointer to raw tunnel option data
- *     @size: size of @opt
- *     Return: option size
- *
- * int bpf_skb_set_tunnel_opt(skb, opt, size)
- *     populate tunnel options metadata
- *     @skb: pointer to skb
- *     @opt: pointer to raw tunnel option data
- *     @size: size of @opt
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_change_proto(skb, proto, flags)
- *     Change protocol of the skb. Currently supported is v4 -> v6,
- *     v6 -> v4 transitions. The helper will also resize the skb. eBPF
- *     program is expected to fill the new headers via skb_store_bytes
- *     and lX_csum_replace.
- *     @skb: pointer to skb
- *     @proto: new skb->protocol type
- *     @flags: reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_change_type(skb, type)
- *     Change packet type of skb.
- *     @skb: pointer to skb
- *     @type: new skb->pkt_type type
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_under_cgroup(skb, map, index)
- *     Check cgroup2 membership of skb
- *     @skb: pointer to skb
- *     @map: pointer to bpf_map in BPF_MAP_TYPE_CGROUP_ARRAY type
- *     @index: index of the cgroup in the bpf_map
- *     Return:
- *       == 0 skb failed the cgroup2 descendant test
- *       == 1 skb succeeded the cgroup2 descendant test
- *        < 0 error
- *
- * u32 bpf_get_hash_recalc(skb)
- *     Retrieve and possibly recalculate skb->hash.
- *     @skb: pointer to skb
- *     Return: hash
+ * 	Return
+ * 		A 64-bit integer containing the current GID and UID, and
+ * 		created as such: *current_gid* **<< 32 \|** *current_uid*.
+ *
+ * int bpf_get_current_comm(char *buf, u32 size_of_buf)
+ * 	Description
+ * 		Copy the **comm** attribute of the current task into *buf* of
+ * 		*size_of_buf*. The **comm** attribute contains the name of
+ * 		the executable (excluding the path) for the current task. The
+ * 		*size_of_buf* must be strictly positive. On success, the
+ * 		helper makes sure that the *buf* is NUL-terminated. On failure,
+ * 		it is filled with zeroes.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * u32 bpf_get_cgroup_classid(struct sk_buff *skb)
+ * 	Description
+ * 		Retrieve the classid for the current task, i.e. for the net_cls
+ * 		cgroup to which *skb* belongs.
+ *
+ * 		This helper can be used on TC egress path, but not on ingress.
+ *
+ * 		The net_cls cgroup provides an interface to tag network packets
+ * 		based on a user-provided identifier for all traffic coming from
+ * 		the tasks belonging to the related cgroup. See also the related
+ * 		kernel documentation, available from the Linux sources in file
+ * 		*Documentation/cgroup-v1/net_cls.txt*.
+ *
+ * 		The Linux kernel has two versions for cgroups: there are
+ * 		cgroups v1 and cgroups v2. Both are available to users, who can
+ * 		use a mixture of them, but note that the net_cls cgroup is for
+ * 		cgroup v1 only. This makes it incompatible with BPF programs
+ * 		run on cgroups, which is a cgroup-v2-only feature (a socket can
+ * 		only hold data for one version of cgroups at a time).
+ *
+ * 		This helper is only available is the kernel was compiled with
+ * 		the **CONFIG_CGROUP_NET_CLASSID** configuration option set to
+ * 		"**y**" or to "**m**".
+ * 	Return
+ * 		The classid, or 0 for the default unconfigured classid.
+ *
+ * int bpf_skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci)
+ * 	Description
+ * 		Push a *vlan_tci* (VLAN tag control information) of protocol
+ * 		*vlan_proto* to the packet associated to *skb*, then update
+ * 		the checksum. Note that if *vlan_proto* is different from
+ * 		**ETH_P_8021Q** and **ETH_P_8021AD**, it is considered to
+ * 		be **ETH_P_8021Q**.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_vlan_pop(struct sk_buff *skb)
+ * 	Description
+ * 		Pop a VLAN header from the packet associated to *skb*.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_get_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags)
+ * 	Description
+ * 		Get tunnel metadata. This helper takes a pointer *key* to an
+ * 		empty **struct bpf_tunnel_key** of **size**, that will be
+ * 		filled with tunnel metadata for the packet associated to *skb*.
+ * 		The *flags* can be set to **BPF_F_TUNINFO_IPV6**, which
+ * 		indicates that the tunnel is based on IPv6 protocol instead of
+ * 		IPv4.
+ *
+ * 		The **struct bpf_tunnel_key** is an object that generalizes the
+ * 		principal parameters used by various tunneling protocols into a
+ * 		single struct. This way, it can be used to easily make a
+ * 		decision based on the contents of the encapsulation header,
+ * 		"summarized" in this struct. In particular, it holds the IP
+ * 		address of the remote end (IPv4 or IPv6, depending on the case)
+ * 		in *key*\ **->remote_ipv4** or *key*\ **->remote_ipv6**. Also,
+ * 		this struct exposes the *key*\ **->tunnel_id**, which is
+ * 		generally mapped to a VNI (Virtual Network Identifier), making
+ * 		it programmable together with the **bpf_skb_set_tunnel_key**\
+ * 		() helper.
+ *
+ * 		Let's imagine that the following code is part of a program
+ * 		attached to the TC ingress interface, on one end of a GRE
+ * 		tunnel, and is supposed to filter out all messages coming from
+ * 		remote ends with IPv4 address other than 10.0.0.1:
+ *
+ * 		::
+ *
+ * 			int ret;
+ * 			struct bpf_tunnel_key key = {};
+ * 			
+ * 			ret = bpf_skb_get_tunnel_key(skb, &key, sizeof(key), 0);
+ * 			if (ret < 0)
+ * 				return TC_ACT_SHOT;	// drop packet
+ * 			
+ * 			if (key.remote_ipv4 != 0x0a000001)
+ * 				return TC_ACT_SHOT;	// drop packet
+ * 			
+ * 			return TC_ACT_OK;		// accept packet
+ *
+ * 		This interface can also be used with all encapsulation devices
+ * 		that can operate in "collect metadata" mode: instead of having
+ * 		one network device per specific configuration, the "collect
+ * 		metadata" mode only requires a single device where the
+ * 		configuration can be extracted from this helper.
+ *
+ * 		This can be used together with various tunnels such as VXLan,
+ * 		Geneve, GRE or IP in IP (IPIP).
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_set_tunnel_key(struct sk_buff *skb, struct bpf_tunnel_key *key, u32 size, u64 flags)
+ * 	Description
+ * 		Populate tunnel metadata for packet associated to *skb.* The
+ * 		tunnel metadata is set to the contents of *key*, of *size*. The
+ * 		*flags* can be set to a combination of the following values:
+ *
+ * 		**BPF_F_TUNINFO_IPV6**
+ * 			Indicate that the tunnel is based on IPv6 protocol
+ * 			instead of IPv4.
+ * 		**BPF_F_ZERO_CSUM_TX**
+ * 			For IPv4 packets, add a flag to tunnel metadata
+ * 			indicating that checksum computation should be skipped
+ * 			and checksum set to zeroes.
+ * 		**BPF_F_DONT_FRAGMENT**
+ * 			Add a flag to tunnel metadata indicating that the
+ * 			packet should not be fragmented.
+ * 		**BPF_F_SEQ_NUMBER**
+ * 			Add a flag to tunnel metadata indicating that a
+ * 			sequence number should be added to tunnel header before
+ * 			sending the packet. This flag was added for GRE
+ * 			encapsulation, but might be used with other protocols
+ * 			as well in the future.
+ *
+ * 		Here is a typical usage on the transmit path:
+ *
+ * 		::
+ *
+ * 			struct bpf_tunnel_key key;
+ * 			     populate key ...
+ * 			bpf_skb_set_tunnel_key(skb, &key, sizeof(key), 0);
+ * 			bpf_clone_redirect(skb, vxlan_dev_ifindex, 0);
+ *
+ * 		See also the description of the **bpf_skb_get_tunnel_key**\ ()
+ * 		helper for additional information.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * u64 bpf_perf_event_read(struct bpf_map *map, u64 flags)
+ * 	Description
+ * 		Read the value of a perf event counter. This helper relies on a
+ * 		*map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of
+ * 		the perf event counter is selected when *map* is updated with
+ * 		perf event file descriptors. The *map* is an array whose size
+ * 		is the number of available CPUs, and each cell contains a value
+ * 		relative to one CPU. The value to retrieve is indicated by
+ * 		*flags*, that contains the index of the CPU to look up, masked
+ * 		with **BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to
+ * 		**BPF_F_CURRENT_CPU** to indicate that the value for the
+ * 		current CPU should be retrieved.
+ *
+ * 		Note that before Linux 4.13, only hardware perf event can be
+ * 		retrieved.
+ *
+ * 		Also, be aware that the newer helper
+ * 		**bpf_perf_event_read_value**\ () is recommended over
+ * 		**bpf_perf_event_read**\ () in general. The latter has some ABI
+ * 		quirks where error and counter value are used as a return code
+ * 		(which is wrong to do since ranges may overlap). This issue is
+ * 		fixed with **bpf_perf_event_read_value**\ (), which at the same
+ * 		time provides more features over the **bpf_perf_event_read**\
+ * 		() interface. Please refer to the description of
+ * 		**bpf_perf_event_read_value**\ () for details.
+ * 	Return
+ * 		The value of the perf event counter read from the map, or a
+ * 		negative error code in case of failure.
+ *
+ * int bpf_redirect(u32 ifindex, u64 flags)
+ * 	Description
+ * 		Redirect the packet to another net device of index *ifindex*.
+ * 		This helper is somewhat similar to **bpf_clone_redirect**\
+ * 		(), except that the packet is not cloned, which provides
+ * 		increased performance.
+ *
+ * 		Except for XDP, both ingress and egress interfaces can be used
+ * 		for redirection. The **BPF_F_INGRESS** value in *flags* is used
+ * 		to make the distinction (ingress path is selected if the flag
+ * 		is present, egress path otherwise). Currently, XDP only
+ * 		supports redirection to the egress interface, and accepts no
+ * 		flag at all.
+ *
+ * 		The same effect can be attained with the more generic
+ * 		**bpf_redirect_map**\ (), which requires specific maps to be
+ * 		used but offers better performance.
+ * 	Return
+ * 		For XDP, the helper returns **XDP_REDIRECT** on success or
+ * 		**XDP_ABORTED** on error. For other program types, the values
+ * 		are **TC_ACT_REDIRECT** on success or **TC_ACT_SHOT** on
+ * 		error.
+ *
+ * u32 bpf_get_route_realm(struct sk_buff *skb)
+ * 	Description
+ * 		Retrieve the realm or the route, that is to say the
+ * 		**tclassid** field of the destination for the *skb*. The
+ * 		indentifier retrieved is a user-provided tag, similar to the
+ * 		one used with the net_cls cgroup (see description for
+ * 		**bpf_get_cgroup_classid**\ () helper), but here this tag is
+ * 		held by a route (a destination entry), not by a task.
+ *
+ * 		Retrieving this identifier works with the clsact TC egress hook
+ * 		(see also **tc-bpf(8)**), or alternatively on conventional
+ * 		classful egress qdiscs, but not on TC ingress path. In case of
+ * 		clsact TC egress hook, this has the advantage that, internally,
+ * 		the destination entry has not been dropped yet in the transmit
+ * 		path. Therefore, the destination entry does not need to be
+ * 		artificially held via **netif_keep_dst**\ () for a classful
+ * 		qdisc until the *skb* is freed.
+ *
+ * 		This helper is available only if the kernel was compiled with
+ * 		**CONFIG_IP_ROUTE_CLASSID** configuration option.
+ * 	Return
+ * 		The realm of the route for the packet associated to *skb*, or 0
+ * 		if none was found.
+ *
+ * int bpf_perf_event_output(struct pt_reg *ctx, struct bpf_map *map, u64 flags, void *data, u64 size)
+ * 	Description
+ * 		Write raw *data* blob into a special BPF perf event held by
+ * 		*map* of type **BPF_MAP_TYPE_PERF_EVENT_ARRAY**. This perf
+ * 		event must have the following attributes: **PERF_SAMPLE_RAW**
+ * 		as **sample_type**, **PERF_TYPE_SOFTWARE** as **type**, and
+ * 		**PERF_COUNT_SW_BPF_OUTPUT** as **config**.
+ *
+ * 		The *flags* are used to indicate the index in *map* for which
+ * 		the value must be put, masked with **BPF_F_INDEX_MASK**.
+ * 		Alternatively, *flags* can be set to **BPF_F_CURRENT_CPU**
+ * 		to indicate that the index of the current CPU core should be
+ * 		used.
+ *
+ * 		The value to write, of *size*, is passed through eBPF stack and
+ * 		pointed by *data*.
+ *
+ * 		The context of the program *ctx* needs also be passed to the
+ * 		helper.
+ *
+ * 		On user space, a program willing to read the values needs to
+ * 		call **perf_event_open**\ () on the perf event (either for
+ * 		one or for all CPUs) and to store the file descriptor into the
+ * 		*map*. This must be done before the eBPF program can send data
+ * 		into it. An example is available in file
+ * 		*samples/bpf/trace_output_user.c* in the Linux kernel source
+ * 		tree (the eBPF program counterpart is in
+ * 		*samples/bpf/trace_output_kern.c*).
+ *
+ * 		**bpf_perf_event_output**\ () achieves better performance
+ * 		than **bpf_trace_printk**\ () for sharing data with user
+ * 		space, and is much better suitable for streaming data from eBPF
+ * 		programs.
+ *
+ * 		Note that this helper is not restricted to tracing use cases
+ * 		and can be used with programs attached to TC or XDP as well,
+ * 		where it allows for passing data to user space listeners. Data
+ * 		can be:
+ *
+ * 		* Only custom structs,
+ * 		* Only the packet payload, or
+ * 		* A combination of both.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_load_bytes(const struct sk_buff *skb, u32 offset, void *to, u32 len)
+ * 	Description
+ * 		This helper was provided as an easy way to load data from a
+ * 		packet. It can be used to load *len* bytes from *offset* from
+ * 		the packet associated to *skb*, into the buffer pointed by
+ * 		*to*.
+ *
+ * 		Since Linux 4.7, usage of this helper has mostly been replaced
+ * 		by "direct packet access", enabling packet data to be
+ * 		manipulated with *skb*\ **->data** and *skb*\ **->data_end**
+ * 		pointing respectively to the first byte of packet data and to
+ * 		the byte after the last byte of packet data. However, it
+ * 		remains useful if one wishes to read large quantities of data
+ * 		at once from a packet into the eBPF stack.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_get_stackid(struct pt_reg *ctx, struct bpf_map *map, u64 flags)
+ * 	Description
+ * 		Walk a user or a kernel stack and return its id. To achieve
+ * 		this, the helper needs *ctx*, which is a pointer to the context
+ * 		on which the tracing program is executed, and a pointer to a
+ * 		*map* of type **BPF_MAP_TYPE_STACK_TRACE**.
+ *
+ * 		The last argument, *flags*, holds the number of stack frames to
+ * 		skip (from 0 to 255), masked with
+ * 		**BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set
+ * 		a combination of the following flags:
+ *
+ * 		**BPF_F_USER_STACK**
+ * 			Collect a user space stack instead of a kernel stack.
+ * 		**BPF_F_FAST_STACK_CMP**
+ * 			Compare stacks by hash only.
+ * 		**BPF_F_REUSE_STACKID**
+ * 			If two different stacks hash into the same *stackid*,
+ * 			discard the old one.
+ *
+ * 		The stack id retrieved is a 32 bit long integer handle which
+ * 		can be further combined with other data (including other stack
+ * 		ids) and used as a key into maps. This can be useful for
+ * 		generating a variety of graphs (such as flame graphs or off-cpu
+ * 		graphs).
+ *
+ * 		For walking a stack, this helper is an improvement over
+ * 		**bpf_probe_read**\ (), which can be used with unrolled loops
+ * 		but is not efficient and consumes a lot of eBPF instructions.
+ * 		Instead, **bpf_get_stackid**\ () can collect up to
+ * 		**PERF_MAX_STACK_DEPTH** both kernel and user frames. Note that
+ * 		this limit can be controlled with the **sysctl** program, and
+ * 		that it should be manually increased in order to profile long
+ * 		user stacks (such as stacks for Java programs). To do so, use:
+ *
+ * 		::
+ *
+ * 			# sysctl kernel.perf_event_max_stack=<new value>
+ * 	Return
+ * 		The positive or null stack id on success, or a negative error
+ * 		in case of failure.
+ *
+ * s64 bpf_csum_diff(__be32 *from, u32 from_size, __be32 *to, u32 to_size, __wsum seed)
+ * 	Description
+ * 		Compute a checksum difference, from the raw buffer pointed by
+ * 		*from*, of length *from_size* (that must be a multiple of 4),
+ * 		towards the raw buffer pointed by *to*, of size *to_size*
+ * 		(same remark). An optional *seed* can be added to the value
+ * 		(this can be cascaded, the seed may come from a previous call
+ * 		to the helper).
+ *
+ * 		This is flexible enough to be used in several ways:
+ *
+ * 		* With *from_size* == 0, *to_size* > 0 and *seed* set to
+ * 		  checksum, it can be used when pushing new data.
+ * 		* With *from_size* > 0, *to_size* == 0 and *seed* set to
+ * 		  checksum, it can be used when removing data from a packet.
+ * 		* With *from_size* > 0, *to_size* > 0 and *seed* set to 0, it
+ * 		  can be used to compute a diff. Note that *from_size* and
+ * 		  *to_size* do not need to be equal.
+ *
+ * 		This helper can be used in combination with
+ * 		**bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\ (), to
+ * 		which one can feed in the difference computed with
+ * 		**bpf_csum_diff**\ ().
+ * 	Return
+ * 		The checksum result, or a negative error code in case of
+ * 		failure.
+ *
+ * int bpf_skb_get_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
+ * 	Description
+ * 		Retrieve tunnel options metadata for the packet associated to
+ * 		*skb*, and store the raw tunnel option data to the buffer *opt*
+ * 		of *size*.
+ *
+ * 		This helper can be used with encapsulation devices that can
+ * 		operate in "collect metadata" mode (please refer to the related
+ * 		note in the description of **bpf_skb_get_tunnel_key**\ () for
+ * 		more details). A particular example where this can be used is
+ * 		in combination with the Geneve encapsulation protocol, where it
+ * 		allows for pushing (with **bpf_skb_get_tunnel_opt**\ () helper)
+ * 		and retrieving arbitrary TLVs (Type-Length-Value headers) from
+ * 		the eBPF program. This allows for full customization of these
+ * 		headers.
+ * 	Return
+ * 		The size of the option data retrieved.
+ *
+ * int bpf_skb_set_tunnel_opt(struct sk_buff *skb, u8 *opt, u32 size)
+ * 	Description
+ * 		Set tunnel options metadata for the packet associated to *skb*
+ * 		to the option data contained in the raw buffer *opt* of *size*.
+ *
+ * 		See also the description of the **bpf_skb_get_tunnel_opt**\ ()
+ * 		helper for additional information.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_change_proto(struct sk_buff *skb, __be16 proto, u64 flags)
+ * 	Description
+ * 		Change the protocol of the *skb* to *proto*. Currently
+ * 		supported are transition from IPv4 to IPv6, and from IPv6 to
+ * 		IPv4. The helper takes care of the groundwork for the
+ * 		transition, including resizing the socket buffer. The eBPF
+ * 		program is expected to fill the new headers, if any, via
+ * 		**skb_store_bytes**\ () and to recompute the checksums with
+ * 		**bpf_l3_csum_replace**\ () and **bpf_l4_csum_replace**\
+ * 		(). The main case for this helper is to perform NAT64
+ * 		operations out of an eBPF program.
+ *
+ * 		Internally, the GSO type is marked as dodgy so that headers are
+ * 		checked and segments are recalculated by the GSO/GRO engine.
+ * 		The size for GSO target is adapted as well.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_change_type(struct sk_buff *skb, u32 type)
+ * 	Description
+ * 		Change the packet type for the packet associated to *skb*. This
+ * 		comes down to setting *skb*\ **->pkt_type** to *type*, except
+ * 		the eBPF program does not have a write access to *skb*\
+ * 		**->pkt_type** beside this helper. Using a helper here allows
+ * 		for graceful handling of errors.
+ *
+ * 		The major use case is to change incoming *skb*s to
+ * 		**PACKET_HOST** in a programmatic way instead of having to
+ * 		recirculate via **redirect**\ (..., **BPF_F_INGRESS**), for
+ * 		example.
+ *
+ * 		Note that *type* only allows certain values. At this time, they
+ * 		are:
+ *
+ * 		**PACKET_HOST**
+ * 			Packet is for us.
+ * 		**PACKET_BROADCAST**
+ * 			Send packet to all.
+ * 		**PACKET_MULTICAST**
+ * 			Send packet to group.
+ * 		**PACKET_OTHERHOST**
+ * 			Send packet to someone else.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_under_cgroup(struct sk_buff *skb, struct bpf_map *map, u32 index)
+ * 	Description
+ * 		Check whether *skb* is a descendant of the cgroup2 held by
+ * 		*map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*.
+ * 	Return
+ * 		The return value depends on the result of the test, and can be:
+ *
+ * 		* 0, if the *skb* failed the cgroup2 descendant test.
+ * 		* 1, if the *skb* succeeded the cgroup2 descendant test.
+ * 		* A negative error code, if an error occurred.
+ *
+ * u32 bpf_get_hash_recalc(struct sk_buff *skb)
+ * 	Description
+ * 		Retrieve the hash of the packet, *skb*\ **->hash**. If it is
+ * 		not set, in particular if the hash was cleared due to mangling,
+ * 		recompute this hash. Later accesses to the hash can be done
+ * 		directly with *skb*\ **->hash**.
+ *
+ * 		Calling **bpf_set_hash_invalid**\ (), changing a packet
+ * 		prototype with **bpf_skb_change_proto**\ (), or calling
+ * 		**bpf_skb_store_bytes**\ () with the
+ * 		**BPF_F_INVALIDATE_HASH** are actions susceptible to clear
+ * 		the hash and to trigger a new computation for the next call to
+ * 		**bpf_get_hash_recalc**\ ().
+ * 	Return
+ * 		The 32-bit hash.
  *
  * u64 bpf_get_current_task(void)
- *     Returns current task_struct
- *     Return: current
- *
- * int bpf_probe_write_user(void *dst, void *src, int len)
- *     safely attempt to write to a location
- *     @dst: destination address in userspace
- *     @src: source address on stack
- *     @len: number of bytes to copy
- *     Return: 0 on success or negative error
- *
- * int bpf_current_task_under_cgroup(map, index)
- *     Check cgroup2 membership of current task
- *     @map: pointer to bpf_map in BPF_MAP_TYPE_CGROUP_ARRAY type
- *     @index: index of the cgroup in the bpf_map
- *     Return:
- *       == 0 current failed the cgroup2 descendant test
- *       == 1 current succeeded the cgroup2 descendant test
- *        < 0 error
- *
- * int bpf_skb_change_tail(skb, len, flags)
- *     The helper will resize the skb to the given new size, to be used f.e.
- *     with control messages.
- *     @skb: pointer to skb
- *     @len: new skb length
- *     @flags: reserved
- *     Return: 0 on success or negative error
- *
- * int bpf_skb_pull_data(skb, len)
- *     The helper will pull in non-linear data in case the skb is non-linear
- *     and not all of len are part of the linear section. Only needed for
- *     read/write with direct packet access.
- *     @skb: pointer to skb
- *     @len: len to make read/writeable
- *     Return: 0 on success or negative error
- *
- * s64 bpf_csum_update(skb, csum)
- *     Adds csum into skb->csum in case of CHECKSUM_COMPLETE.
- *     @skb: pointer to skb
- *     @csum: csum to add
- *     Return: csum on success or negative error
- *
- * void bpf_set_hash_invalid(skb)
- *     Invalidate current skb->hash.
- *     @skb: pointer to skb
- *
- * int bpf_get_numa_node_id()
- *     Return: Id of current NUMA node.
- *
- * int bpf_skb_change_head()
- *     Grows headroom of skb and adjusts MAC header offset accordingly.
- *     Will extends/reallocae as required automatically.
- *     May change skb data pointer and will thus invalidate any check
- *     performed for direct packet access.
- *     @skb: pointer to skb
- *     @len: length of header to be pushed in front
- *     @flags: Flags (unused for now)
- *     Return: 0 on success or negative error
- *
- * int bpf_xdp_adjust_head(xdp_md, delta)
- *     Adjust the xdp_md.data by delta
- *     @xdp_md: pointer to xdp_md
- *     @delta: An positive/negative integer to be added to xdp_md.data
- *     Return: 0 on success or negative on error
+ * 	Return
+ * 		A pointer to the current task struct.
+ *
+ * int bpf_probe_write_user(void *dst, const void *src, u32 len)
+ * 	Description
+ * 		Attempt in a safe way to write *len* bytes from the buffer
+ * 		*src* to *dst* in memory. It only works for threads that are in
+ * 		user context, and *dst* must be a valid user space address.
+ *
+ * 		This helper should not be used to implement any kind of
+ * 		security mechanism because of TOC-TOU attacks, but rather to
+ * 		debug, divert, and manipulate execution of semi-cooperative
+ * 		processes.
+ *
+ * 		Keep in mind that this feature is meant for experiments, and it
+ * 		has a risk of crashing the system and running programs.
+ * 		Therefore, when an eBPF program using this helper is attached,
+ * 		a warning including PID and process name is printed to kernel
+ * 		logs.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_current_task_under_cgroup(struct bpf_map *map, u32 index)
+ * 	Description
+ * 		Check whether the probe is being run is the context of a given
+ * 		subset of the cgroup2 hierarchy. The cgroup2 to test is held by
+ * 		*map* of type **BPF_MAP_TYPE_CGROUP_ARRAY**, at *index*.
+ * 	Return
+ * 		The return value depends on the result of the test, and can be:
+ *
+ * 		* 0, if the *skb* task belongs to the cgroup2.
+ * 		* 1, if the *skb* task does not belong to the cgroup2.
+ * 		* A negative error code, if an error occurred.
+ *
+ * int bpf_skb_change_tail(struct sk_buff *skb, u32 len, u64 flags)
+ * 	Description
+ * 		Resize (trim or grow) the packet associated to *skb* to the
+ * 		new *len*. The *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		The basic idea is that the helper performs the needed work to
+ * 		change the size of the packet, then the eBPF program rewrites
+ * 		the rest via helpers like **bpf_skb_store_bytes**\ (),
+ * 		**bpf_l3_csum_replace**\ (), **bpf_l3_csum_replace**\ ()
+ * 		and others. This helper is a slow path utility intended for
+ * 		replies with control messages. And because it is targeted for
+ * 		slow path, the helper itself can afford to be slow: it
+ * 		implicitly linearizes, unclones and drops offloads from the
+ * 		*skb*.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_pull_data(struct sk_buff *skb, u32 len)
+ * 	Description
+ * 		Pull in non-linear data in case the *skb* is non-linear and not
+ * 		all of *len* are part of the linear section. Make *len* bytes
+ * 		from *skb* readable and writable. If a zero value is passed for
+ * 		*len*, then the whole length of the *skb* is pulled.
+ *
+ * 		This helper is only needed for reading and writing with direct
+ * 		packet access.
+ *
+ * 		For direct packet access, testing that offsets to access
+ * 		are within packet boundaries (test on *skb*\ **->data_end**) is
+ * 		susceptible to fail if offsets are invalid, or if the requested
+ * 		data is in non-linear parts of the *skb*. On failure the
+ * 		program can just bail out, or in the case of a non-linear
+ * 		buffer, use a helper to make the data available. The
+ * 		**bpf_skb_load_bytes**\ () helper is a first solution to access
+ * 		the data. Another one consists in using **bpf_skb_pull_data**
+ * 		to pull in once the non-linear parts, then retesting and
+ * 		eventually access the data.
+ *
+ * 		At the same time, this also makes sure the *skb* is uncloned,
+ * 		which is a necessary condition for direct write. As this needs
+ * 		to be an invariant for the write part only, the verifier
+ * 		detects writes and adds a prologue that is calling
+ * 		**bpf_skb_pull_data()** to effectively unclone the *skb* from
+ * 		the very beginning in case it is indeed cloned.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * s64 bpf_csum_update(struct sk_buff *skb, __wsum csum)
+ * 	Description
+ * 		Add the checksum *csum* into *skb*\ **->csum** in case the
+ * 		driver has supplied a checksum for the entire packet into that
+ * 		field. Return an error otherwise. This helper is intended to be
+ * 		used in combination with **bpf_csum_diff**\ (), in particular
+ * 		when the checksum needs to be updated after data has been
+ * 		written into the packet through direct packet access.
+ * 	Return
+ * 		The checksum on success, or a negative error code in case of
+ * 		failure.
+ *
+ * void bpf_set_hash_invalid(struct sk_buff *skb)
+ * 	Description
+ * 		Invalidate the current *skb*\ **->hash**. It can be used after
+ * 		mangling on headers through direct packet access, in order to
+ * 		indicate that the hash is outdated and to trigger a
+ * 		recalculation the next time the kernel tries to access this
+ * 		hash or when the **bpf_get_hash_recalc**\ () helper is called.
+ *
+ * int bpf_get_numa_node_id(void)
+ * 	Description
+ * 		Return the id of the current NUMA node. The primary use case
+ * 		for this helper is the selection of sockets for the local NUMA
+ * 		node, when the program is attached to sockets using the
+ * 		**SO_ATTACH_REUSEPORT_EBPF** option (see also **socket(7)**),
+ * 		but the helper is also available to other eBPF program types,
+ * 		similarly to **bpf_get_smp_processor_id**\ ().
+ * 	Return
+ * 		The id of current NUMA node.
+ *
+ * int bpf_skb_change_head(struct sk_buff *skb, u32 len, u64 flags)
+ * 	Description
+ * 		Grows headroom of packet associated to *skb* and adjusts the
+ * 		offset of the MAC header accordingly, adding *len* bytes of
+ * 		space. It automatically extends and reallocates memory as
+ * 		required.
+ *
+ * 		This helper can be used on a layer 3 *skb* to push a MAC header
+ * 		for redirection into a layer 2 device.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_xdp_adjust_head(struct xdp_buff *xdp_md, int delta)
+ * 	Description
+ * 		Adjust (move) *xdp_md*\ **->data** by *delta* bytes. Note that
+ * 		it is possible to use a negative value for *delta*. This helper
+ * 		can be used to prepare the packet for pushing or popping
+ * 		headers.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
  *
  * int bpf_probe_read_str(void *dst, int size, const void *unsafe_ptr)
- *     Copy a NUL terminated string from unsafe address. In case the string
- *     length is smaller than size, the target is not padded with further NUL
- *     bytes. In case the string length is larger than size, just count-1
- *     bytes are copied and the last byte is set to NUL.
- *     @dst: destination address
- *     @size: maximum number of bytes to copy, including the trailing NUL
- *     @unsafe_ptr: unsafe address
- *     Return:
- *       > 0 length of the string including the trailing NUL on success
- *       < 0 error
- *
- * u64 bpf_get_socket_cookie(skb)
- *     Get the cookie for the socket stored inside sk_buff.
- *     @skb: pointer to skb
- *     Return: 8 Bytes non-decreasing number on success or 0 if the socket
- *     field is missing inside sk_buff
- *
- * u32 bpf_get_socket_uid(skb)
- *     Get the owner uid of the socket stored inside sk_buff.
- *     @skb: pointer to skb
- *     Return: uid of the socket owner on success or overflowuid if failed.
- *
- * u32 bpf_set_hash(skb, hash)
- *     Set full skb->hash.
- *     @skb: pointer to skb
- *     @hash: hash to set
- *
- * int bpf_setsockopt(bpf_socket, level, optname, optval, optlen)
- *     Calls setsockopt. Not all opts are available, only those with
- *     integer optvals plus TCP_CONGESTION.
- *     Supported levels: SOL_SOCKET and IPPROTO_TCP
- *     @bpf_socket: pointer to bpf_socket
- *     @level: SOL_SOCKET or IPPROTO_TCP
- *     @optname: option name
- *     @optval: pointer to option value
- *     @optlen: length of optval in bytes
- *     Return: 0 or negative error
- *
- * int bpf_getsockopt(bpf_socket, level, optname, optval, optlen)
- *     Calls getsockopt. Not all opts are available.
- *     Supported levels: IPPROTO_TCP
- *     @bpf_socket: pointer to bpf_socket
- *     @level: IPPROTO_TCP
- *     @optname: option name
- *     @optval: pointer to option value
- *     @optlen: length of optval in bytes
- *     Return: 0 or negative error
- *
- * int bpf_sock_ops_cb_flags_set(bpf_sock_ops, flags)
- *     Set callback flags for sock_ops
- *     @bpf_sock_ops: pointer to bpf_sock_ops_kern struct
- *     @flags: flags value
- *     Return: 0 for no error
- *             -EINVAL if there is no full tcp socket
- *             bits in flags that are not supported by current kernel
- *
- * int bpf_skb_adjust_room(skb, len_diff, mode, flags)
- *     Grow or shrink room in sk_buff.
- *     @skb: pointer to skb
- *     @len_diff: (signed) amount of room to grow/shrink
- *     @mode: operation mode (enum bpf_adj_room_mode)
- *     @flags: reserved for future use
- *     Return: 0 on success or negative error code
- *
- * int bpf_sk_redirect_map(map, key, flags)
- *     Redirect skb to a sock in map using key as a lookup key for the
- *     sock in map.
- *     @map: pointer to sockmap
- *     @key: key to lookup sock in map
- *     @flags: reserved for future use
- *     Return: SK_PASS
- *
- * int bpf_sock_map_update(skops, map, key, flags)
- *	@skops: pointer to bpf_sock_ops
- *	@map: pointer to sockmap to update
- *	@key: key to insert/update sock in map
- *	@flags: same flags as map update elem
- *
- * int bpf_xdp_adjust_meta(xdp_md, delta)
- *     Adjust the xdp_md.data_meta by delta
- *     @xdp_md: pointer to xdp_md
- *     @delta: An positive/negative integer to be added to xdp_md.data_meta
- *     Return: 0 on success or negative on error
- *
- * int bpf_perf_event_read_value(map, flags, buf, buf_size)
- *     read perf event counter value and perf event enabled/running time
- *     @map: pointer to perf_event_array map
- *     @flags: index of event in the map or bitmask flags
- *     @buf: buf to fill
- *     @buf_size: size of the buf
- *     Return: 0 on success or negative error code
- *
- * int bpf_perf_prog_read_value(ctx, buf, buf_size)
- *     read perf prog attached perf event counter and enabled/running time
- *     @ctx: pointer to ctx
- *     @buf: buf to fill
- *     @buf_size: size of the buf
- *     Return : 0 on success or negative error code
- *
- * int bpf_override_return(pt_regs, rc)
- *	@pt_regs: pointer to struct pt_regs
- *	@rc: the return value to set
- *
- * int bpf_msg_redirect_map(map, key, flags)
- *     Redirect msg to a sock in map using key as a lookup key for the
- *     sock in map.
- *     @map: pointer to sockmap
- *     @key: key to lookup sock in map
- *     @flags: reserved for future use
- *     Return: SK_PASS
- *
- * int bpf_bind(ctx, addr, addr_len)
- *     Bind socket to address. Only binding to IP is supported, no port can be
- *     set in addr.
- *     @ctx: pointer to context of type bpf_sock_addr
- *     @addr: pointer to struct sockaddr to bind socket to
- *     @addr_len: length of sockaddr structure
- *     Return: 0 on success or negative error code
+ * 	Description
+ * 		Copy a NUL terminated string from an unsafe address
+ * 		*unsafe_ptr* to *dst*. The *size* should include the
+ * 		terminating NUL byte. In case the string length is smaller than
+ * 		*size*, the target is not padded with further NUL bytes. If the
+ * 		string length is larger than *size*, just *size*-1 bytes are
+ * 		copied and the last byte is set to NUL.
+ *
+ * 		On success, the length of the copied string is returned. This
+ * 		makes this helper useful in tracing programs for reading
+ * 		strings, and more importantly to get its length at runtime. See
+ * 		the following snippet:
+ *
+ * 		::
+ *
+ * 			SEC("kprobe/sys_open")
+ * 			void bpf_sys_open(struct pt_regs *ctx)
+ * 			{
+ * 			        char buf[PATHLEN]; // PATHLEN is defined to 256
+ * 			        int res = bpf_probe_read_str(buf, sizeof(buf),
+ * 				                             ctx->di);
+ *
+ * 				// Consume buf, for example push it to
+ * 				// userspace via bpf_perf_event_output(); we
+ * 				// can use res (the string length) as event
+ * 				// size, after checking its boundaries.
+ * 			}
+ *
+ * 		In comparison, using **bpf_probe_read()** helper here instead
+ * 		to read the string would require to estimate the length at
+ * 		compile time, and would often result in copying more memory
+ * 		than necessary.
+ *
+ * 		Another useful use case is when parsing individual process
+ * 		arguments or individual environment variables navigating
+ * 		*current*\ **->mm->arg_start** and *current*\
+ * 		**->mm->env_start**: using this helper and the return value,
+ * 		one can quickly iterate at the right offset of the memory area.
+ * 	Return
+ * 		On success, the strictly positive length of the string,
+ * 		including the trailing NUL character. On error, a negative
+ * 		value.
+ *
+ * u64 bpf_get_socket_cookie(struct sk_buff *skb)
+ * 	Description
+ * 		If the **struct sk_buff** pointed by *skb* has a known socket,
+ * 		retrieve the cookie (generated by the kernel) of this socket.
+ * 		If no cookie has been set yet, generate a new cookie. Once
+ * 		generated, the socket cookie remains stable for the life of the
+ * 		socket. This helper can be useful for monitoring per socket
+ * 		networking traffic statistics as it provides a unique socket
+ * 		identifier per namespace.
+ * 	Return
+ * 		A 8-byte long non-decreasing number on success, or 0 if the
+ * 		socket field is missing inside *skb*.
+ *
+ * u32 bpf_get_socket_uid(struct sk_buff *skb)
+ * 	Return
+ * 		The owner UID of the socket associated to *skb*. If the socket
+ * 		is **NULL**, or if it is not a full socket (i.e. if it is a
+ * 		time-wait or a request socket instead), **overflowuid** value
+ * 		is returned (note that **overflowuid** might also be the actual
+ * 		UID value for the socket).
+ *
+ * u32 bpf_set_hash(struct sk_buff *skb, u32 hash)
+ * 	Description
+ * 		Set the full hash for *skb* (set the field *skb*\ **->hash**)
+ * 		to value *hash*.
+ * 	Return
+ * 		0
+ *
+ * int bpf_setsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen)
+ * 	Description
+ * 		Emulate a call to **setsockopt()** on the socket associated to
+ * 		*bpf_socket*, which must be a full socket. The *level* at
+ * 		which the option resides and the name *optname* of the option
+ * 		must be specified, see **setsockopt(2)** for more information.
+ * 		The option value of length *optlen* is pointed by *optval*.
+ *
+ * 		This helper actually implements a subset of **setsockopt()**.
+ * 		It supports the following *level*\ s:
+ *
+ * 		* **SOL_SOCKET**, which supports the following *optname*\ s:
+ * 		  **SO_RCVBUF**, **SO_SNDBUF**, **SO_MAX_PACING_RATE**,
+ * 		  **SO_PRIORITY**, **SO_RCVLOWAT**, **SO_MARK**.
+ * 		* **IPPROTO_TCP**, which supports the following *optname*\ s:
+ * 		  **TCP_CONGESTION**, **TCP_BPF_IW**,
+ * 		  **TCP_BPF_SNDCWND_CLAMP**.
+ * 		* **IPPROTO_IP**, which supports *optname* **IP_TOS**.
+ * 		* **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_adjust_room(struct sk_buff *skb, u32 len_diff, u32 mode, u64 flags)
+ * 	Description
+ * 		Grow or shrink the room for data in the packet associated to
+ * 		*skb* by *len_diff*, and according to the selected *mode*.
+ *
+ * 		There is a single supported mode at this time:
+ *
+ * 		* **BPF_ADJ_ROOM_NET**: Adjust room at the network layer
+ * 		  (room space is added or removed below the layer 3 header).
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_redirect_map(struct bpf_map *map, u32 key, u64 flags)
+ * 	Description
+ * 		Redirect the packet to the endpoint referenced by *map* at
+ * 		index *key*. Depending on its type, this *map* can contain
+ * 		references to net devices (for forwarding packets through other
+ * 		ports), or to CPUs (for redirecting XDP frames to another CPU;
+ * 		but this is only implemented for native XDP (with driver
+ * 		support) as of this writing).
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		When used to redirect packets to net devices, this helper
+ * 		provides a high performance increase over **bpf_redirect**\ ().
+ * 		This is due to various implementation details of the underlying
+ * 		mechanisms, one of which is the fact that **bpf_redirect_map**\
+ * 		() tries to send packet as a "bulk" to the device.
+ * 	Return
+ * 		**XDP_REDIRECT** on success, or **XDP_ABORTED** on error.
+ *
+ * int bpf_sk_redirect_map(struct bpf_map *map, u32 key, u64 flags)
+ * 	Description
+ * 		Redirect the packet to the socket referenced by *map* (of type
+ * 		**BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
+ * 		egress interfaces can be used for redirection. The
+ * 		**BPF_F_INGRESS** value in *flags* is used to make the
+ * 		distinction (ingress path is selected if the flag is present,
+ * 		egress path otherwise). This is the only flag supported for now.
+ * 	Return
+ * 		**SK_PASS** on success, or **SK_DROP** on error.
+ *
+ * int bpf_sock_map_update(struct bpf_sock_ops *skops, struct bpf_map *map, void *key, u64 flags)
+ * 	Description
+ * 		Add an entry to, or update a *map* referencing sockets. The
+ * 		*skops* is used as a new value for the entry associated to
+ * 		*key*. *flags* is one of:
+ *
+ * 		**BPF_NOEXIST**
+ * 			The entry for *key* must not exist in the map.
+ * 		**BPF_EXIST**
+ * 			The entry for *key* must already exist in the map.
+ * 		**BPF_ANY**
+ * 			No condition on the existence of the entry for *key*.
+ *
+ * 		If the *map* has eBPF programs (parser and verdict), those will
+ * 		be inherited by the socket being added. If the socket is
+ * 		already attached to eBPF programs, this results in an error.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_xdp_adjust_meta(struct xdp_buff *xdp_md, int delta)
+ * 	Description
+ * 		Adjust the address pointed by *xdp_md*\ **->data_meta** by
+ * 		*delta* (which can be positive or negative). Note that this
+ * 		operation modifies the address stored in *xdp_md*\ **->data**,
+ * 		so the latter must be loaded only after the helper has been
+ * 		called.
+ *
+ * 		The use of *xdp_md*\ **->data_meta** is optional and programs
+ * 		are not required to use it. The rationale is that when the
+ * 		packet is processed with XDP (e.g. as DoS filter), it is
+ * 		possible to push further meta data along with it before passing
+ * 		to the stack, and to give the guarantee that an ingress eBPF
+ * 		program attached as a TC classifier on the same device can pick
+ * 		this up for further post-processing. Since TC works with socket
+ * 		buffers, it remains possible to set from XDP the **mark** or
+ * 		**priority** pointers, or other pointers for the socket buffer.
+ * 		Having this scratch space generic and programmable allows for
+ * 		more flexibility as the user is free to store whatever meta
+ * 		data they need.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_perf_event_read_value(struct bpf_map *map, u64 flags, struct bpf_perf_event_value *buf, u32 buf_size)
+ * 	Description
+ * 		Read the value of a perf event counter, and store it into *buf*
+ * 		of size *buf_size*. This helper relies on a *map* of type
+ * 		**BPF_MAP_TYPE_PERF_EVENT_ARRAY**. The nature of the perf event
+ * 		counter is selected when *map* is updated with perf event file
+ * 		descriptors. The *map* is an array whose size is the number of
+ * 		available CPUs, and each cell contains a value relative to one
+ * 		CPU. The value to retrieve is indicated by *flags*, that
+ * 		contains the index of the CPU to look up, masked with
+ * 		**BPF_F_INDEX_MASK**. Alternatively, *flags* can be set to
+ * 		**BPF_F_CURRENT_CPU** to indicate that the value for the
+ * 		current CPU should be retrieved.
+ *
+ * 		This helper behaves in a way close to
+ * 		**bpf_perf_event_read**\ () helper, save that instead of
+ * 		just returning the value observed, it fills the *buf*
+ * 		structure. This allows for additional data to be retrieved: in
+ * 		particular, the enabled and running times (in *buf*\
+ * 		**->enabled** and *buf*\ **->running**, respectively) are
+ * 		copied. In general, **bpf_perf_event_read_value**\ () is
+ * 		recommended over **bpf_perf_event_read**\ (), which has some
+ * 		ABI issues and provides fewer functionalities.
+ *
+ * 		These values are interesting, because hardware PMU (Performance
+ * 		Monitoring Unit) counters are limited resources. When there are
+ * 		more PMU based perf events opened than available counters,
+ * 		kernel will multiplex these events so each event gets certain
+ * 		percentage (but not all) of the PMU time. In case that
+ * 		multiplexing happens, the number of samples or counter value
+ * 		will not reflect the case compared to when no multiplexing
+ * 		occurs. This makes comparison between different runs difficult.
+ * 		Typically, the counter value should be normalized before
+ * 		comparing to other experiments. The usual normalization is done
+ * 		as follows.
+ *
+ * 		::
+ *
+ * 			normalized_counter = counter * t_enabled / t_running
+ *
+ * 		Where t_enabled is the time enabled for event and t_running is
+ * 		the time running for event since last normalization. The
+ * 		enabled and running times are accumulated since the perf event
+ * 		open. To achieve scaling factor between two invocations of an
+ * 		eBPF program, users can can use CPU id as the key (which is
+ * 		typical for perf array usage model) to remember the previous
+ * 		value and do the calculation inside the eBPF program.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_perf_prog_read_value(struct bpf_perf_event_data *ctx, struct bpf_perf_event_value *buf, u32 buf_size)
+ * 	Description
+ * 		For en eBPF program attached to a perf event, retrieve the
+ * 		value of the event counter associated to *ctx* and store it in
+ * 		the structure pointed by *buf* and of size *buf_size*. Enabled
+ * 		and running times are also stored in the structure (see
+ * 		description of helper **bpf_perf_event_read_value**\ () for
+ * 		more details).
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_getsockopt(struct bpf_sock_ops *bpf_socket, int level, int optname, char *optval, int optlen)
+ * 	Description
+ * 		Emulate a call to **getsockopt()** on the socket associated to
+ * 		*bpf_socket*, which must be a full socket. The *level* at
+ * 		which the option resides and the name *optname* of the option
+ * 		must be specified, see **getsockopt(2)** for more information.
+ * 		The retrieved value is stored in the structure pointed by
+ * 		*opval* and of length *optlen*.
+ *
+ * 		This helper actually implements a subset of **getsockopt()**.
+ * 		It supports the following *level*\ s:
+ *
+ * 		* **IPPROTO_TCP**, which supports *optname*
+ * 		  **TCP_CONGESTION**.
+ * 		* **IPPROTO_IP**, which supports *optname* **IP_TOS**.
+ * 		* **IPPROTO_IPV6**, which supports *optname* **IPV6_TCLASS**.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_override_return(struct pt_reg *regs, u64 rc)
+ * 	Description
+ * 		Used for error injection, this helper uses kprobes to override
+ * 		the return value of the probed function, and to set it to *rc*.
+ * 		The first argument is the context *regs* on which the kprobe
+ * 		works.
+ *
+ * 		This helper works by setting setting the PC (program counter)
+ * 		to an override function which is run in place of the original
+ * 		probed function. This means the probed function is not run at
+ * 		all. The replacement function just returns with the required
+ * 		value.
+ *
+ * 		This helper has security implications, and thus is subject to
+ * 		restrictions. It is only available if the kernel was compiled
+ * 		with the **CONFIG_BPF_KPROBE_OVERRIDE** configuration
+ * 		option, and in this case it only works on functions tagged with
+ * 		**ALLOW_ERROR_INJECTION** in the kernel code.
+ *
+ * 		Also, the helper is only available for the architectures having
+ * 		the CONFIG_FUNCTION_ERROR_INJECTION option. As of this writing,
+ * 		x86 architecture is the only one to support this feature.
+ * 	Return
+ * 		0
+ *
+ * int bpf_sock_ops_cb_flags_set(struct bpf_sock_ops *bpf_sock, int argval)
+ * 	Description
+ * 		Attempt to set the value of the **bpf_sock_ops_cb_flags** field
+ * 		for the full TCP socket associated to *bpf_sock_ops* to
+ * 		*argval*.
+ *
+ * 		The primary use of this field is to determine if there should
+ * 		be calls to eBPF programs of type
+ * 		**BPF_PROG_TYPE_SOCK_OPS** at various points in the TCP
+ * 		code. A program of the same type can change its value, per
+ * 		connection and as necessary, when the connection is
+ * 		established. This field is directly accessible for reading, but
+ * 		this helper must be used for updates in order to return an
+ * 		error if an eBPF program tries to set a callback that is not
+ * 		supported in the current kernel.
+ *
+ * 		The supported callback values that *argval* can combine are:
+ *
+ * 		* **BPF_SOCK_OPS_RTO_CB_FLAG** (retransmission time out)
+ * 		* **BPF_SOCK_OPS_RETRANS_CB_FLAG** (retransmission)
+ * 		* **BPF_SOCK_OPS_STATE_CB_FLAG** (TCP state change)
+ *
+ * 		Here are some examples of where one could call such eBPF
+ * 		program:
+ *
+ * 		* When RTO fires.
+ * 		* When a packet is retransmitted.
+ * 		* When the connection terminates.
+ * 		* When a packet is sent.
+ * 		* When a packet is received.
+ * 	Return
+ * 		Code **-EINVAL** if the socket is not a full TCP socket;
+ * 		otherwise, a positive number containing the bits that could not
+ * 		be set is returned (which comes down to 0 if all bits were set
+ * 		as required).
+ *
+ * int bpf_msg_redirect_map(struct sk_msg_buff *msg, struct bpf_map *map, u32 key, u64 flags)
+ * 	Description
+ * 		This helper is used in programs implementing policies at the
+ * 		socket level. If the message *msg* is allowed to pass (i.e. if
+ * 		the verdict eBPF program returns **SK_PASS**), redirect it to
+ * 		the socket referenced by *map* (of type
+ * 		**BPF_MAP_TYPE_SOCKMAP**) at index *key*. Both ingress and
+ * 		egress interfaces can be used for redirection. The
+ * 		**BPF_F_INGRESS** value in *flags* is used to make the
+ * 		distinction (ingress path is selected if the flag is present,
+ * 		egress path otherwise). This is the only flag supported for now.
+ * 	Return
+ * 		**SK_PASS** on success, or **SK_DROP** on error.
+ *
+ * int bpf_msg_apply_bytes(struct sk_msg_buff *msg, u32 bytes)
+ * 	Description
+ * 		For socket policies, apply the verdict of the eBPF program to
+ * 		the next *bytes* (number of bytes) of message *msg*.
+ *
+ * 		For example, this helper can be used in the following cases:
+ *
+ * 		* A single **sendmsg**\ () or **sendfile**\ () system call
+ * 		  contains multiple logical messages that the eBPF program is
+ * 		  supposed to read and for which it should apply a verdict.
+ * 		* An eBPF program only cares to read the first *bytes* of a
+ * 		  *msg*. If the message has a large payload, then setting up
+ * 		  and calling the eBPF program repeatedly for all bytes, even
+ * 		  though the verdict is already known, would create unnecessary
+ * 		  overhead.
+ *
+ * 		When called from within an eBPF program, the helper sets a
+ * 		counter internal to the BPF infrastructure, that is used to
+ * 		apply the last verdict to the next *bytes*. If *bytes* is
+ * 		smaller than the current data being processed from a
+ * 		**sendmsg**\ () or **sendfile**\ () system call, the first
+ * 		*bytes* will be sent and the eBPF program will be re-run with
+ * 		the pointer for start of data pointing to byte number *bytes*
+ * 		**+ 1**. If *bytes* is larger than the current data being
+ * 		processed, then the eBPF verdict will be applied to multiple
+ * 		**sendmsg**\ () or **sendfile**\ () calls until *bytes* are
+ * 		consumed.
+ *
+ * 		Note that if a socket closes with the internal counter holding
+ * 		a non-zero value, this is not a problem because data is not
+ * 		being buffered for *bytes* and is sent as it is received.
+ * 	Return
+ * 		0
+ *
+ * int bpf_msg_cork_bytes(struct sk_msg_buff *msg, u32 bytes)
+ * 	Description
+ * 		For socket policies, prevent the execution of the verdict eBPF
+ * 		program for message *msg* until *bytes* (byte number) have been
+ * 		accumulated.
+ *
+ * 		This can be used when one needs a specific number of bytes
+ * 		before a verdict can be assigned, even if the data spans
+ * 		multiple **sendmsg**\ () or **sendfile**\ () calls. The extreme
+ * 		case would be a user calling **sendmsg**\ () repeatedly with
+ * 		1-byte long message segments. Obviously, this is bad for
+ * 		performance, but it is still valid. If the eBPF program needs
+ * 		*bytes* bytes to validate a header, this helper can be used to
+ * 		prevent the eBPF program to be called again until *bytes* have
+ * 		been accumulated.
+ * 	Return
+ * 		0
+ *
+ * int bpf_msg_pull_data(struct sk_msg_buff *msg, u32 start, u32 end, u64 flags)
+ * 	Description
+ * 		For socket policies, pull in non-linear data from user space
+ * 		for *msg* and set pointers *msg*\ **->data** and *msg*\
+ * 		**->data_end** to *start* and *end* bytes offsets into *msg*,
+ * 		respectively.
+ *
+ * 		If a program of type **BPF_PROG_TYPE_SK_MSG** is run on a
+ * 		*msg* it can only parse data that the (**data**, **data_end**)
+ * 		pointers have already consumed. For **sendmsg**\ () hooks this
+ * 		is likely the first scatterlist element. But for calls relying
+ * 		on the **sendpage** handler (e.g. **sendfile**\ ()) this will
+ * 		be the range (**0**, **0**) because the data is shared with
+ * 		user space and by default the objective is to avoid allowing
+ * 		user space to modify data while (or after) eBPF verdict is
+ * 		being decided. This helper can be used to pull in data and to
+ * 		set the start and end pointer to given values. Data will be
+ * 		copied if necessary (i.e. if data was not linear and if start
+ * 		and end pointers do not point to the same chunk).
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_bind(struct bpf_sock_addr *ctx, struct sockaddr *addr, int addr_len)
+ * 	Description
+ * 		Bind the socket associated to *ctx* to the address pointed by
+ * 		*addr*, of length *addr_len*. This allows for making outgoing
+ * 		connection from the desired IP address, which can be useful for
+ * 		example when all processes inside a cgroup should use one
+ * 		single IP address on a host that has multiple IP configured.
+ *
+ * 		This helper works for IPv4 and IPv6, TCP and UDP sockets. The
+ * 		domain (*addr*\ **->sa_family**) must be **AF_INET** (or
+ * 		**AF_INET6**). Looking for a free port to bind to can be
+ * 		expensive, therefore binding to port is not permitted by the
+ * 		helper: *addr*\ **->sin_port** (or **sin6_port**, respectively)
+ * 		must be set to zero.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_xdp_adjust_tail(struct xdp_buff *xdp_md, int delta)
+ * 	Description
+ * 		Adjust (move) *xdp_md*\ **->data_end** by *delta* bytes. It is
+ * 		only possible to shrink the packet as of this writing,
+ * 		therefore *delta* must be a negative integer.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_skb_get_xfrm_state(struct sk_buff *skb, u32 index, struct bpf_xfrm_state *xfrm_state, u32 size, u64 flags)
+ * 	Description
+ * 		Retrieve the XFRM state (IP transform framework, see also
+ * 		**ip-xfrm(8)**) at *index* in XFRM "security path" for *skb*.
+ *
+ * 		The retrieved value is stored in the **struct bpf_xfrm_state**
+ * 		pointed by *xfrm_state* and of length *size*.
+ *
+ * 		All values for *flags* are reserved for future usage, and must
+ * 		be left at zero.
+ *
+ * 		This helper is available only if the kernel was compiled with
+ * 		**CONFIG_XFRM** configuration option.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_get_stack(struct pt_regs *regs, void *buf, u32 size, u64 flags)
+ * 	Description
+ * 		Return a user or a kernel stack in bpf program provided buffer.
+ * 		To achieve this, the helper needs *ctx*, which is a pointer
+ * 		to the context on which the tracing program is executed.
+ * 		To store the stacktrace, the bpf program provides *buf* with
+ * 		a nonnegative *size*.
+ *
+ * 		The last argument, *flags*, holds the number of stack frames to
+ * 		skip (from 0 to 255), masked with
+ * 		**BPF_F_SKIP_FIELD_MASK**. The next bits can be used to set
+ * 		the following flags:
+ *
+ * 		**BPF_F_USER_STACK**
+ * 			Collect a user space stack instead of a kernel stack.
+ * 		**BPF_F_USER_BUILD_ID**
+ * 			Collect buildid+offset instead of ips for user stack,
+ * 			only valid if **BPF_F_USER_STACK** is also specified.
+ *
+ * 		**bpf_get_stack**\ () can collect up to
+ * 		**PERF_MAX_STACK_DEPTH** both kernel and user frames, subject
+ * 		to sufficient large buffer size. Note that
+ * 		this limit can be controlled with the **sysctl** program, and
+ * 		that it should be manually increased in order to profile long
+ * 		user stacks (such as stacks for Java programs). To do so, use:
+ *
+ * 		::
+ *
+ * 			# sysctl kernel.perf_event_max_stack=<new value>
+ * 	Return
+ * 		A non-negative value equal to or less than *size* on success,
+ * 		or a negative error in case of failure.
+ *
+ * int skb_load_bytes_relative(const struct sk_buff *skb, u32 offset, void *to, u32 len, u32 start_header)
+ * 	Description
+ * 		This helper is similar to **bpf_skb_load_bytes**\ () in that
+ * 		it provides an easy way to load *len* bytes from *offset*
+ * 		from the packet associated to *skb*, into the buffer pointed
+ * 		by *to*. The difference to **bpf_skb_load_bytes**\ () is that
+ * 		a fifth argument *start_header* exists in order to select a
+ * 		base offset to start from. *start_header* can be one of:
+ *
+ * 		**BPF_HDR_START_MAC**
+ * 			Base offset to load data from is *skb*'s mac header.
+ * 		**BPF_HDR_START_NET**
+ * 			Base offset to load data from is *skb*'s network header.
+ *
+ * 		In general, "direct packet access" is the preferred method to
+ * 		access packet data, however, this helper is in particular useful
+ * 		in socket filters where *skb*\ **->data** does not always point
+ * 		to the start of the mac header and where "direct packet access"
+ * 		is not available.
+ * 	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_fib_lookup(void *ctx, struct bpf_fib_lookup *params, int plen, u32 flags)
+ *	Description
+ *		Do FIB lookup in kernel tables using parameters in *params*.
+ *		If lookup is successful and result shows packet is to be
+ *		forwarded, the neighbor tables are searched for the nexthop.
+ *		If successful (ie., FIB lookup shows forwarding and nexthop
+ *		is resolved), the nexthop address is returned in ipv4_dst
+ *		or ipv6_dst based on family, smac is set to mac address of
+ *		egress device, dmac is set to nexthop mac address, rt_metric
+ *		is set to metric from route (IPv4/IPv6 only).
+ *
+ *             *plen* argument is the size of the passed in struct.
+ *             *flags* argument can be a combination of one or more of the
+ *             following values:
+ *
+ *		**BPF_FIB_LOOKUP_DIRECT**
+ *			Do a direct table lookup vs full lookup using FIB
+ *			rules.
+ *		**BPF_FIB_LOOKUP_OUTPUT**
+ *			Perform lookup from an egress perspective (default is
+ *			ingress).
+ *
+ *             *ctx* is either **struct xdp_md** for XDP programs or
+ *             **struct sk_buff** tc cls_act programs.
+ *     Return
+ *             Egress device index on success, 0 if packet needs to continue
+ *             up the stack for further processing or a negative error in case
+ *             of failure.
+ *
+ * int bpf_sock_hash_update(struct bpf_sock_ops_kern *skops, struct bpf_map *map, void *key, u64 flags)
+ *	Description
+ *		Add an entry to, or update a sockhash *map* referencing sockets.
+ *		The *skops* is used as a new value for the entry associated to
+ *		*key*. *flags* is one of:
+ *
+ *		**BPF_NOEXIST**
+ *			The entry for *key* must not exist in the map.
+ *		**BPF_EXIST**
+ *			The entry for *key* must already exist in the map.
+ *		**BPF_ANY**
+ *			No condition on the existence of the entry for *key*.
+ *
+ *		If the *map* has eBPF programs (parser and verdict), those will
+ *		be inherited by the socket being added. If the socket is
+ *		already attached to eBPF programs, this results in an error.
+ *	Return
+ *		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_msg_redirect_hash(struct sk_msg_buff *msg, struct bpf_map *map, void *key, u64 flags)
+ *	Description
+ *		This helper is used in programs implementing policies at the
+ *		socket level. If the message *msg* is allowed to pass (i.e. if
+ *		the verdict eBPF program returns **SK_PASS**), redirect it to
+ *		the socket referenced by *map* (of type
+ *		**BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and
+ *		egress interfaces can be used for redirection. The
+ *		**BPF_F_INGRESS** value in *flags* is used to make the
+ *		distinction (ingress path is selected if the flag is present,
+ *		egress path otherwise). This is the only flag supported for now.
+ *	Return
+ *		**SK_PASS** on success, or **SK_DROP** on error.
+ *
+ * int bpf_sk_redirect_hash(struct sk_buff *skb, struct bpf_map *map, void *key, u64 flags)
+ *	Description
+ *		This helper is used in programs implementing policies at the
+ *		skb socket level. If the sk_buff *skb* is allowed to pass (i.e.
+ *		if the verdeict eBPF program returns **SK_PASS**), redirect it
+ *		to the socket referenced by *map* (of type
+ *		**BPF_MAP_TYPE_SOCKHASH**) using hash *key*. Both ingress and
+ *		egress interfaces can be used for redirection. The
+ *		**BPF_F_INGRESS** value in *flags* is used to make the
+ *		distinction (ingress path is selected if the flag is present,
+ *		egress otherwise). This is the only flag supported for now.
+ *	Return
+ *		**SK_PASS** on success, or **SK_DROP** on error.
+ *
+ * int bpf_lwt_push_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
+ *	Description
+ *		Encapsulate the packet associated to *skb* within a Layer 3
+ *		protocol header. This header is provided in the buffer at
+ *		address *hdr*, with *len* its size in bytes. *type* indicates
+ *		the protocol of the header and can be one of:
+ *
+ *		**BPF_LWT_ENCAP_SEG6**
+ *			IPv6 encapsulation with Segment Routing Header
+ *			(**struct ipv6_sr_hdr**). *hdr* only contains the SRH,
+ *			the IPv6 header is computed by the kernel.
+ *		**BPF_LWT_ENCAP_SEG6_INLINE**
+ *			Only works if *skb* contains an IPv6 packet. Insert a
+ *			Segment Routing Header (**struct ipv6_sr_hdr**) inside
+ *			the IPv6 header.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ *	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_lwt_seg6_store_bytes(struct sk_buff *skb, u32 offset, const void *from, u32 len)
+ *	Description
+ *		Store *len* bytes from address *from* into the packet
+ *		associated to *skb*, at *offset*. Only the flags, tag and TLVs
+ *		inside the outermost IPv6 Segment Routing Header can be
+ *		modified through this helper.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ *	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_lwt_seg6_adjust_srh(struct sk_buff *skb, u32 offset, s32 delta)
+ *	Description
+ *		Adjust the size allocated to TLVs in the outermost IPv6
+ *		Segment Routing Header contained in the packet associated to
+ *		*skb*, at position *offset* by *delta* bytes. Only offsets
+ *		after the segments are accepted. *delta* can be as well
+ *		positive (growing) as negative (shrinking).
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ *	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_lwt_seg6_action(struct sk_buff *skb, u32 action, void *param, u32 param_len)
+ *	Description
+ *		Apply an IPv6 Segment Routing action of type *action* to the
+ *		packet associated to *skb*. Each action takes a parameter
+ *		contained at address *param*, and of length *param_len* bytes.
+ *		*action* can be one of:
+ *
+ *		**SEG6_LOCAL_ACTION_END_X**
+ *			End.X action: Endpoint with Layer-3 cross-connect.
+ *			Type of *param*: **struct in6_addr**.
+ *		**SEG6_LOCAL_ACTION_END_T**
+ *			End.T action: Endpoint with specific IPv6 table lookup.
+ *			Type of *param*: **int**.
+ *		**SEG6_LOCAL_ACTION_END_B6**
+ *			End.B6 action: Endpoint bound to an SRv6 policy.
+ *			Type of param: **struct ipv6_sr_hdr**.
+ *		**SEG6_LOCAL_ACTION_END_B6_ENCAP**
+ *			End.B6.Encap action: Endpoint bound to an SRv6
+ *			encapsulation policy.
+ *			Type of param: **struct ipv6_sr_hdr**.
+ *
+ * 		A call to this helper is susceptible to change the underlaying
+ * 		packet buffer. Therefore, at load time, all checks on pointers
+ * 		previously done by the verifier are invalidated and must be
+ * 		performed again, if the helper is used in combination with
+ * 		direct packet access.
+ *	Return
+ * 		0 on success, or a negative error in case of failure.
+ *
+ * int bpf_rc_keydown(void *ctx, u32 protocol, u64 scancode, u32 toggle)
+ *	Description
+ *		This helper is used in programs implementing IR decoding, to
+ *		report a successfully decoded key press with *scancode*,
+ *		*toggle* value in the given *protocol*. The scancode will be
+ *		translated to a keycode using the rc keymap, and reported as
+ *		an input key down event. After a period a key up event is
+ *		generated. This period can be extended by calling either
+ *		**bpf_rc_keydown** () again with the same values, or calling
+ *		**bpf_rc_repeat** ().
+ *
+ *		Some protocols include a toggle bit, in case the button	was
+ *		released and pressed again between consecutive scancodes.
+ *
+ *		The *ctx* should point to the lirc sample as passed into
+ *		the program.
+ *
+ *		The *protocol* is the decoded protocol number (see
+ *		**enum rc_proto** for some predefined values).
+ *
+ *		This helper is only available is the kernel was compiled with
+ *		the **CONFIG_BPF_LIRC_MODE2** configuration option set to
+ *		"**y**".
+ *
+ *	Return
+ *		0
+ *
+ * int bpf_rc_repeat(void *ctx)
+ *	Description
+ *		This helper is used in programs implementing IR decoding, to
+ *		report a successfully decoded repeat key message. This delays
+ *		the generation of a key up event for previously generated
+ *		key down event.
+ *
+ *		Some IR protocols like NEC have a special IR message for
+ *		repeating last button, for when a button is held down.
+ *
+ *		The *ctx* should point to the lirc sample as passed into
+ *		the program.
+ *
+ *		This helper is only available is the kernel was compiled with
+ *		the **CONFIG_BPF_LIRC_MODE2** configuration option set to
+ *		"**y**".
+ *
+ *	Return
+ *		0
+ *
+ * uint64_t bpf_skb_cgroup_id(struct sk_buff *skb)
+ * 	Description
+ * 		Return the cgroup v2 id of the socket associated with the *skb*.
+ * 		This is roughly similar to the **bpf_get_cgroup_classid**\ ()
+ * 		helper for cgroup v1 by providing a tag resp. identifier that
+ * 		can be matched on or used for map lookups e.g. to implement
+ * 		policy. The cgroup v2 id of a given path in the hierarchy is
+ * 		exposed in user space through the f_handle API in order to get
+ * 		to the same 64-bit id.
+ *
+ * 		This helper can be used on TC egress path, but not on ingress,
+ * 		and is available only if the kernel was compiled with the
+ * 		**CONFIG_SOCK_CGROUP_DATA** configuration option.
+ * 	Return
+ * 		The id is returned or 0 in case the id could not be retrieved.
+ *
+ * u64 bpf_get_current_cgroup_id(void)
+ * 	Return
+ * 		A 64-bit integer containing the current cgroup id based
+ * 		on the cgroup within which the current task is running.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -821,7 +2141,23 @@ union bpf_attr {
 	FN(msg_apply_bytes),		\
 	FN(msg_cork_bytes),		\
 	FN(msg_pull_data),		\
-	FN(bind),
+	FN(bind),			\
+	FN(xdp_adjust_tail),		\
+	FN(skb_get_xfrm_state),		\
+	FN(get_stack),			\
+	FN(skb_load_bytes_relative),	\
+	FN(fib_lookup),			\
+	FN(sock_hash_update),		\
+	FN(msg_redirect_hash),		\
+	FN(sk_redirect_hash),		\
+	FN(lwt_push_encap),		\
+	FN(lwt_seg6_store_bytes),	\
+	FN(lwt_seg6_adjust_srh),	\
+	FN(lwt_seg6_action),		\
+	FN(rc_repeat),			\
+	FN(rc_keydown),			\
+	FN(skb_cgroup_id),		\
+	FN(get_current_cgroup_id),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
@@ -855,11 +2191,14 @@ enum bpf_func_id {
 /* BPF_FUNC_skb_set_tunnel_key and BPF_FUNC_skb_get_tunnel_key flags. */
 #define BPF_F_TUNINFO_IPV6		(1ULL << 0)
 
-/* BPF_FUNC_get_stackid flags. */
+/* flags for both BPF_FUNC_get_stackid and BPF_FUNC_get_stack. */
 #define BPF_F_SKIP_FIELD_MASK		0xffULL
 #define BPF_F_USER_STACK		(1ULL << 8)
+/* flags used by BPF_FUNC_get_stackid only. */
 #define BPF_F_FAST_STACK_CMP		(1ULL << 9)
 #define BPF_F_REUSE_STACKID		(1ULL << 10)
+/* flags used by BPF_FUNC_get_stack only. */
+#define BPF_F_USER_BUILD_ID		(1ULL << 11)
 
 /* BPF_FUNC_skb_set_tunnel_key flags. */
 #define BPF_F_ZERO_CSUM_TX		(1ULL << 1)
@@ -879,6 +2218,18 @@ enum bpf_adj_room_mode {
 	BPF_ADJ_ROOM_NET,
 };
 
+/* Mode for BPF_FUNC_skb_load_bytes_relative helper. */
+enum bpf_hdr_start_off {
+	BPF_HDR_START_MAC,
+	BPF_HDR_START_NET,
+};
+
+/* Encapsulation type for BPF_FUNC_lwt_push_encap helper. */
+enum bpf_lwt_encap_mode {
+	BPF_LWT_ENCAP_SEG6,
+	BPF_LWT_ENCAP_SEG6_INLINE
+};
+
 /* user accessible mirror of in-kernel sk_buff.
  * new fields can only be added to the end of this structure
  */
@@ -923,10 +2274,24 @@ struct bpf_tunnel_key {
 	};
 	__u8 tunnel_tos;
 	__u8 tunnel_ttl;
-	__u16 tunnel_ext;
+	__u16 tunnel_ext;	/* Padding, future use. */
 	__u32 tunnel_label;
 };
 
+/* user accessible mirror of in-kernel xfrm_state.
+ * new fields can only be added to the end of this structure
+ */
+struct bpf_xfrm_state {
+	__u32 reqid;
+	__u32 spi;	/* Stored in network byte order */
+	__u16 family;
+	__u16 ext;	/* Padding, future use. */
+	union {
+		__u32 remote_ipv4;	/* Stored in network byte order */
+		__u32 remote_ipv6[4];	/* Stored in network byte order */
+	};
+};
+
 /* Generic BPF return codes which all BPF program types may support.
  * The values are binary compatible with their TC_ACT_* counter-part to
  * provide backwards compatibility with existing SCHED_CLS and SCHED_ACT
@@ -999,6 +2364,14 @@ enum sk_action {
 struct sk_msg_md {
 	void *data;
 	void *data_end;
+
+	__u32 family;
+	__u32 remote_ip4;	/* Stored in network byte order */
+	__u32 local_ip4;	/* Stored in network byte order */
+	__u32 remote_ip6[4];	/* Stored in network byte order */
+	__u32 local_ip6[4];	/* Stored in network byte order */
+	__u32 remote_port;	/* Stored in network byte order */
+	__u32 local_port;	/* stored in host byte order */
 };
 
 #define BPF_TAG_SIZE	8
@@ -1017,9 +2390,13 @@ struct bpf_prog_info {
 	__aligned_u64 map_ids;
 	char name[BPF_OBJ_NAME_LEN];
 	__u32 ifindex;
-	__u32 :32;
+	__u32 gpl_compatible:1;
 	__u64 netns_dev;
 	__u64 netns_ino;
+	__u32 nr_jited_ksyms;
+	__u32 nr_jited_func_lens;
+	__aligned_u64 jited_ksyms;
+	__aligned_u64 jited_func_lens;
 } __attribute__((aligned(8)));
 
 struct bpf_map_info {
@@ -1034,6 +2411,15 @@ struct bpf_map_info {
 	__u32 :32;
 	__u64 netns_dev;
 	__u64 netns_ino;
+	__u32 btf_id;
+	__u32 btf_key_type_id;
+	__u32 btf_value_type_id;
+} __attribute__((aligned(8)));
+
+struct bpf_btf_info {
+	__aligned_u64 btf;
+	__u32 btf_size;
+	__u32 id;
 } __attribute__((aligned(8)));
 
 /* User bpf_sock_addr struct to access socket fields and sockaddr struct passed
@@ -1054,6 +2440,12 @@ struct bpf_sock_addr {
 	__u32 family;		/* Allows 4-byte read, but no write */
 	__u32 type;		/* Allows 4-byte read, but no write */
 	__u32 protocol;		/* Allows 4-byte read, but no write */
+	__u32 msg_src_ip4;	/* Allows 1,2,4-byte read an 4-byte write.
+				 * Stored in network byte order.
+				 */
+	__u32 msg_src_ip6[4];	/* Allows 1,2,4-byte read an 4-byte write.
+				 * Stored in network byte order.
+				 */
 };
 
 /* User bpf_sock_ops struct to access socket values and specify request ops
@@ -1214,4 +2606,64 @@ struct bpf_raw_tracepoint_args {
 	__u64 args[0];
 };
 
+/* DIRECT:  Skip the FIB rules and go to FIB table associated with device
+ * OUTPUT:  Do lookup from egress perspective; default is ingress
+ */
+#define BPF_FIB_LOOKUP_DIRECT  BIT(0)
+#define BPF_FIB_LOOKUP_OUTPUT  BIT(1)
+
+struct bpf_fib_lookup {
+	/* input:  network family for lookup (AF_INET, AF_INET6)
+	 * output: network family of egress nexthop
+	 */
+	__u8	family;
+
+	/* set if lookup is to consider L4 data - e.g., FIB rules */
+	__u8	l4_protocol;
+	__be16	sport;
+	__be16	dport;
+
+	/* total length of packet from network header - used for MTU check */
+	__u16	tot_len;
+	__u32	ifindex;  /* L3 device index for lookup */
+
+	union {
+		/* inputs to lookup */
+		__u8	tos;		/* AF_INET  */
+		__be32	flowlabel;	/* AF_INET6 */
+
+		/* output: metric of fib result (IPv4/IPv6 only) */
+		__u32	rt_metric;
+	};
+
+	union {
+		__be32		ipv4_src;
+		__u32		ipv6_src[4];  /* in6_addr; network order */
+	};
+
+	/* input to bpf_fib_lookup, ipv{4,6}_dst is destination address in
+	 * network header. output: bpf_fib_lookup sets to gateway address
+	 * if FIB lookup returns gateway route
+	 */
+	union {
+		__be32		ipv4_dst;
+		__u32		ipv6_dst[4];  /* in6_addr; network order */
+	};
+
+	/* output */
+	__be16	h_vlan_proto;
+	__be16	h_vlan_TCI;
+	__u8	smac[6];     /* ETH_ALEN */
+	__u8	dmac[6];     /* ETH_ALEN */
+};
+
+enum bpf_task_fd_type {
+	BPF_FD_TYPE_RAW_TRACEPOINT,	/* tp name */
+	BPF_FD_TYPE_TRACEPOINT,		/* tp name */
+	BPF_FD_TYPE_KPROBE,		/* (symbol + offset) or addr */
+	BPF_FD_TYPE_KRETPROBE,		/* (symbol + offset) or addr */
+	BPF_FD_TYPE_UPROBE,		/* filename + offset */
+	BPF_FD_TYPE_URETPROBE,		/* filename + offset */
+};
+
 #endif /* _UAPI__LINUX_BPF_H__ */
diff --git a/tools/include/uapi/linux/btf.h b/tools/include/uapi/linux/btf.h
new file mode 100644
index 000000000000..0b5ddbe135a4
--- /dev/null
+++ b/tools/include/uapi/linux/btf.h
@@ -0,0 +1,113 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* Copyright (c) 2018 Facebook */
+#ifndef _UAPI__LINUX_BTF_H__
+#define _UAPI__LINUX_BTF_H__
+
+#include <linux/types.h>
+
+#define BTF_MAGIC	0xeB9F
+#define BTF_VERSION	1
+
+struct btf_header {
+	__u16	magic;
+	__u8	version;
+	__u8	flags;
+	__u32	hdr_len;
+
+	/* All offsets are in bytes relative to the end of this header */
+	__u32	type_off;	/* offset of type section	*/
+	__u32	type_len;	/* length of type section	*/
+	__u32	str_off;	/* offset of string section	*/
+	__u32	str_len;	/* length of string section	*/
+};
+
+/* Max # of type identifier */
+#define BTF_MAX_TYPE	0x0000ffff
+/* Max offset into the string section */
+#define BTF_MAX_NAME_OFFSET	0x0000ffff
+/* Max # of struct/union/enum members or func args */
+#define BTF_MAX_VLEN	0xffff
+
+struct btf_type {
+	__u32 name_off;
+	/* "info" bits arrangement
+	 * bits  0-15: vlen (e.g. # of struct's members)
+	 * bits 16-23: unused
+	 * bits 24-27: kind (e.g. int, ptr, array...etc)
+	 * bits 28-31: unused
+	 */
+	__u32 info;
+	/* "size" is used by INT, ENUM, STRUCT and UNION.
+	 * "size" tells the size of the type it is describing.
+	 *
+	 * "type" is used by PTR, TYPEDEF, VOLATILE, CONST and RESTRICT.
+	 * "type" is a type_id referring to another type.
+	 */
+	union {
+		__u32 size;
+		__u32 type;
+	};
+};
+
+#define BTF_INFO_KIND(info)	(((info) >> 24) & 0x0f)
+#define BTF_INFO_VLEN(info)	((info) & 0xffff)
+
+#define BTF_KIND_UNKN		0	/* Unknown	*/
+#define BTF_KIND_INT		1	/* Integer	*/
+#define BTF_KIND_PTR		2	/* Pointer	*/
+#define BTF_KIND_ARRAY		3	/* Array	*/
+#define BTF_KIND_STRUCT		4	/* Struct	*/
+#define BTF_KIND_UNION		5	/* Union	*/
+#define BTF_KIND_ENUM		6	/* Enumeration	*/
+#define BTF_KIND_FWD		7	/* Forward	*/
+#define BTF_KIND_TYPEDEF	8	/* Typedef	*/
+#define BTF_KIND_VOLATILE	9	/* Volatile	*/
+#define BTF_KIND_CONST		10	/* Const	*/
+#define BTF_KIND_RESTRICT	11	/* Restrict	*/
+#define BTF_KIND_MAX		11
+#define NR_BTF_KINDS		12
+
+/* For some specific BTF_KIND, "struct btf_type" is immediately
+ * followed by extra data.
+ */
+
+/* BTF_KIND_INT is followed by a u32 and the following
+ * is the 32 bits arrangement:
+ */
+#define BTF_INT_ENCODING(VAL)	(((VAL) & 0x0f000000) >> 24)
+#define BTF_INT_OFFSET(VAL)	(((VAL  & 0x00ff0000)) >> 16)
+#define BTF_INT_BITS(VAL)	((VAL)  & 0x0000ffff)
+
+/* Attributes stored in the BTF_INT_ENCODING */
+#define BTF_INT_SIGNED	(1 << 0)
+#define BTF_INT_CHAR	(1 << 1)
+#define BTF_INT_BOOL	(1 << 2)
+
+/* BTF_KIND_ENUM is followed by multiple "struct btf_enum".
+ * The exact number of btf_enum is stored in the vlen (of the
+ * info in "struct btf_type").
+ */
+struct btf_enum {
+	__u32	name_off;
+	__s32	val;
+};
+
+/* BTF_KIND_ARRAY is followed by one "struct btf_array" */
+struct btf_array {
+	__u32	type;
+	__u32	index_type;
+	__u32	nelems;
+};
+
+/* BTF_KIND_STRUCT and BTF_KIND_UNION are followed
+ * by multiple "struct btf_member".  The exact number
+ * of btf_member is stored in the vlen (of the info in
+ * "struct btf_type").
+ */
+struct btf_member {
+	__u32	name_off;
+	__u32	type;
+	__u32	offset;	/* offset in bits */
+};
+
+#endif /* _UAPI__LINUX_BTF_H__ */
diff --git a/tools/include/uapi/linux/erspan.h b/tools/include/uapi/linux/erspan.h
new file mode 100644
index 000000000000..841573019ae1
--- /dev/null
+++ b/tools/include/uapi/linux/erspan.h
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * ERSPAN Tunnel Metadata
+ *
+ * Copyright (c) 2018 VMware
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * Userspace API for metadata mode ERSPAN tunnel
+ */
+#ifndef _UAPI_ERSPAN_H
+#define _UAPI_ERSPAN_H
+
+#include <linux/types.h>	/* For __beXX in userspace */
+#include <asm/byteorder.h>
+
+/* ERSPAN version 2 metadata header */
+struct erspan_md2 {
+	__be32 timestamp;
+	__be16 sgt;	/* security group tag */
+#if defined(__LITTLE_ENDIAN_BITFIELD)
+	__u8	hwid_upper:2,
+		ft:5,
+		p:1;
+	__u8	o:1,
+		gra:2,
+		dir:1,
+		hwid:4;
+#elif defined(__BIG_ENDIAN_BITFIELD)
+	__u8	p:1,
+		ft:5,
+		hwid_upper:2;
+	__u8	hwid:4,
+		dir:1,
+		gra:2,
+		o:1;
+#else
+#error "Please fix <asm/byteorder.h>"
+#endif
+};
+
+struct erspan_metadata {
+	int version;
+	union {
+		__be32 index;		/* Version 1 (type II)*/
+		struct erspan_md2 md2;	/* Version 2 (type III) */
+	} u;
+};
+
+#endif /* _UAPI_ERSPAN_H */
diff --git a/tools/include/uapi/linux/lirc.h b/tools/include/uapi/linux/lirc.h
new file mode 100644
index 000000000000..f189931042a7
--- /dev/null
+++ b/tools/include/uapi/linux/lirc.h
@@ -0,0 +1,217 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * lirc.h - linux infrared remote control header file
+ * last modified 2010/07/13 by Jarod Wilson
+ */
+
+#ifndef _LINUX_LIRC_H
+#define _LINUX_LIRC_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+#define PULSE_BIT       0x01000000
+#define PULSE_MASK      0x00FFFFFF
+
+#define LIRC_MODE2_SPACE     0x00000000
+#define LIRC_MODE2_PULSE     0x01000000
+#define LIRC_MODE2_FREQUENCY 0x02000000
+#define LIRC_MODE2_TIMEOUT   0x03000000
+
+#define LIRC_VALUE_MASK      0x00FFFFFF
+#define LIRC_MODE2_MASK      0xFF000000
+
+#define LIRC_SPACE(val) (((val)&LIRC_VALUE_MASK) | LIRC_MODE2_SPACE)
+#define LIRC_PULSE(val) (((val)&LIRC_VALUE_MASK) | LIRC_MODE2_PULSE)
+#define LIRC_FREQUENCY(val) (((val)&LIRC_VALUE_MASK) | LIRC_MODE2_FREQUENCY)
+#define LIRC_TIMEOUT(val) (((val)&LIRC_VALUE_MASK) | LIRC_MODE2_TIMEOUT)
+
+#define LIRC_VALUE(val) ((val)&LIRC_VALUE_MASK)
+#define LIRC_MODE2(val) ((val)&LIRC_MODE2_MASK)
+
+#define LIRC_IS_SPACE(val) (LIRC_MODE2(val) == LIRC_MODE2_SPACE)
+#define LIRC_IS_PULSE(val) (LIRC_MODE2(val) == LIRC_MODE2_PULSE)
+#define LIRC_IS_FREQUENCY(val) (LIRC_MODE2(val) == LIRC_MODE2_FREQUENCY)
+#define LIRC_IS_TIMEOUT(val) (LIRC_MODE2(val) == LIRC_MODE2_TIMEOUT)
+
+/* used heavily by lirc userspace */
+#define lirc_t int
+
+/*** lirc compatible hardware features ***/
+
+#define LIRC_MODE2SEND(x) (x)
+#define LIRC_SEND2MODE(x) (x)
+#define LIRC_MODE2REC(x) ((x) << 16)
+#define LIRC_REC2MODE(x) ((x) >> 16)
+
+#define LIRC_MODE_RAW                  0x00000001
+#define LIRC_MODE_PULSE                0x00000002
+#define LIRC_MODE_MODE2                0x00000004
+#define LIRC_MODE_SCANCODE             0x00000008
+#define LIRC_MODE_LIRCCODE             0x00000010
+
+
+#define LIRC_CAN_SEND_RAW              LIRC_MODE2SEND(LIRC_MODE_RAW)
+#define LIRC_CAN_SEND_PULSE            LIRC_MODE2SEND(LIRC_MODE_PULSE)
+#define LIRC_CAN_SEND_MODE2            LIRC_MODE2SEND(LIRC_MODE_MODE2)
+#define LIRC_CAN_SEND_LIRCCODE         LIRC_MODE2SEND(LIRC_MODE_LIRCCODE)
+
+#define LIRC_CAN_SEND_MASK             0x0000003f
+
+#define LIRC_CAN_SET_SEND_CARRIER      0x00000100
+#define LIRC_CAN_SET_SEND_DUTY_CYCLE   0x00000200
+#define LIRC_CAN_SET_TRANSMITTER_MASK  0x00000400
+
+#define LIRC_CAN_REC_RAW               LIRC_MODE2REC(LIRC_MODE_RAW)
+#define LIRC_CAN_REC_PULSE             LIRC_MODE2REC(LIRC_MODE_PULSE)
+#define LIRC_CAN_REC_MODE2             LIRC_MODE2REC(LIRC_MODE_MODE2)
+#define LIRC_CAN_REC_SCANCODE          LIRC_MODE2REC(LIRC_MODE_SCANCODE)
+#define LIRC_CAN_REC_LIRCCODE          LIRC_MODE2REC(LIRC_MODE_LIRCCODE)
+
+#define LIRC_CAN_REC_MASK              LIRC_MODE2REC(LIRC_CAN_SEND_MASK)
+
+#define LIRC_CAN_SET_REC_CARRIER       (LIRC_CAN_SET_SEND_CARRIER << 16)
+#define LIRC_CAN_SET_REC_DUTY_CYCLE    (LIRC_CAN_SET_SEND_DUTY_CYCLE << 16)
+
+#define LIRC_CAN_SET_REC_DUTY_CYCLE_RANGE 0x40000000
+#define LIRC_CAN_SET_REC_CARRIER_RANGE    0x80000000
+#define LIRC_CAN_GET_REC_RESOLUTION       0x20000000
+#define LIRC_CAN_SET_REC_TIMEOUT          0x10000000
+#define LIRC_CAN_SET_REC_FILTER           0x08000000
+
+#define LIRC_CAN_MEASURE_CARRIER          0x02000000
+#define LIRC_CAN_USE_WIDEBAND_RECEIVER    0x04000000
+
+#define LIRC_CAN_SEND(x) ((x)&LIRC_CAN_SEND_MASK)
+#define LIRC_CAN_REC(x) ((x)&LIRC_CAN_REC_MASK)
+
+#define LIRC_CAN_NOTIFY_DECODE            0x01000000
+
+/*** IOCTL commands for lirc driver ***/
+
+#define LIRC_GET_FEATURES              _IOR('i', 0x00000000, __u32)
+
+#define LIRC_GET_SEND_MODE             _IOR('i', 0x00000001, __u32)
+#define LIRC_GET_REC_MODE              _IOR('i', 0x00000002, __u32)
+#define LIRC_GET_REC_RESOLUTION        _IOR('i', 0x00000007, __u32)
+
+#define LIRC_GET_MIN_TIMEOUT           _IOR('i', 0x00000008, __u32)
+#define LIRC_GET_MAX_TIMEOUT           _IOR('i', 0x00000009, __u32)
+
+/* code length in bits, currently only for LIRC_MODE_LIRCCODE */
+#define LIRC_GET_LENGTH                _IOR('i', 0x0000000f, __u32)
+
+#define LIRC_SET_SEND_MODE             _IOW('i', 0x00000011, __u32)
+#define LIRC_SET_REC_MODE              _IOW('i', 0x00000012, __u32)
+/* Note: these can reset the according pulse_width */
+#define LIRC_SET_SEND_CARRIER          _IOW('i', 0x00000013, __u32)
+#define LIRC_SET_REC_CARRIER           _IOW('i', 0x00000014, __u32)
+#define LIRC_SET_SEND_DUTY_CYCLE       _IOW('i', 0x00000015, __u32)
+#define LIRC_SET_TRANSMITTER_MASK      _IOW('i', 0x00000017, __u32)
+
+/*
+ * when a timeout != 0 is set the driver will send a
+ * LIRC_MODE2_TIMEOUT data packet, otherwise LIRC_MODE2_TIMEOUT is
+ * never sent, timeout is disabled by default
+ */
+#define LIRC_SET_REC_TIMEOUT           _IOW('i', 0x00000018, __u32)
+
+/* 1 enables, 0 disables timeout reports in MODE2 */
+#define LIRC_SET_REC_TIMEOUT_REPORTS   _IOW('i', 0x00000019, __u32)
+
+/*
+ * if enabled from the next key press on the driver will send
+ * LIRC_MODE2_FREQUENCY packets
+ */
+#define LIRC_SET_MEASURE_CARRIER_MODE	_IOW('i', 0x0000001d, __u32)
+
+/*
+ * to set a range use LIRC_SET_REC_CARRIER_RANGE with the
+ * lower bound first and later LIRC_SET_REC_CARRIER with the upper bound
+ */
+#define LIRC_SET_REC_CARRIER_RANGE     _IOW('i', 0x0000001f, __u32)
+
+#define LIRC_SET_WIDEBAND_RECEIVER     _IOW('i', 0x00000023, __u32)
+
+/*
+ * struct lirc_scancode - decoded scancode with protocol for use with
+ *	LIRC_MODE_SCANCODE
+ *
+ * @timestamp: Timestamp in nanoseconds using CLOCK_MONOTONIC when IR
+ *	was decoded.
+ * @flags: should be 0 for transmit. When receiving scancodes,
+ *	LIRC_SCANCODE_FLAG_TOGGLE or LIRC_SCANCODE_FLAG_REPEAT can be set
+ *	depending on the protocol
+ * @rc_proto: see enum rc_proto
+ * @keycode: the translated keycode. Set to 0 for transmit.
+ * @scancode: the scancode received or to be sent
+ */
+struct lirc_scancode {
+	__u64	timestamp;
+	__u16	flags;
+	__u16	rc_proto;
+	__u32	keycode;
+	__u64	scancode;
+};
+
+/* Set if the toggle bit of rc-5 or rc-6 is enabled */
+#define LIRC_SCANCODE_FLAG_TOGGLE	1
+/* Set if this is a nec or sanyo repeat */
+#define LIRC_SCANCODE_FLAG_REPEAT	2
+
+/**
+ * enum rc_proto - the Remote Controller protocol
+ *
+ * @RC_PROTO_UNKNOWN: Protocol not known
+ * @RC_PROTO_OTHER: Protocol known but proprietary
+ * @RC_PROTO_RC5: Philips RC5 protocol
+ * @RC_PROTO_RC5X_20: Philips RC5x 20 bit protocol
+ * @RC_PROTO_RC5_SZ: StreamZap variant of RC5
+ * @RC_PROTO_JVC: JVC protocol
+ * @RC_PROTO_SONY12: Sony 12 bit protocol
+ * @RC_PROTO_SONY15: Sony 15 bit protocol
+ * @RC_PROTO_SONY20: Sony 20 bit protocol
+ * @RC_PROTO_NEC: NEC protocol
+ * @RC_PROTO_NECX: Extended NEC protocol
+ * @RC_PROTO_NEC32: NEC 32 bit protocol
+ * @RC_PROTO_SANYO: Sanyo protocol
+ * @RC_PROTO_MCIR2_KBD: RC6-ish MCE keyboard
+ * @RC_PROTO_MCIR2_MSE: RC6-ish MCE mouse
+ * @RC_PROTO_RC6_0: Philips RC6-0-16 protocol
+ * @RC_PROTO_RC6_6A_20: Philips RC6-6A-20 protocol
+ * @RC_PROTO_RC6_6A_24: Philips RC6-6A-24 protocol
+ * @RC_PROTO_RC6_6A_32: Philips RC6-6A-32 protocol
+ * @RC_PROTO_RC6_MCE: MCE (Philips RC6-6A-32 subtype) protocol
+ * @RC_PROTO_SHARP: Sharp protocol
+ * @RC_PROTO_XMP: XMP protocol
+ * @RC_PROTO_CEC: CEC protocol
+ * @RC_PROTO_IMON: iMon Pad protocol
+ */
+enum rc_proto {
+	RC_PROTO_UNKNOWN	= 0,
+	RC_PROTO_OTHER		= 1,
+	RC_PROTO_RC5		= 2,
+	RC_PROTO_RC5X_20	= 3,
+	RC_PROTO_RC5_SZ		= 4,
+	RC_PROTO_JVC		= 5,
+	RC_PROTO_SONY12		= 6,
+	RC_PROTO_SONY15		= 7,
+	RC_PROTO_SONY20		= 8,
+	RC_PROTO_NEC		= 9,
+	RC_PROTO_NECX		= 10,
+	RC_PROTO_NEC32		= 11,
+	RC_PROTO_SANYO		= 12,
+	RC_PROTO_MCIR2_KBD	= 13,
+	RC_PROTO_MCIR2_MSE	= 14,
+	RC_PROTO_RC6_0		= 15,
+	RC_PROTO_RC6_6A_20	= 16,
+	RC_PROTO_RC6_6A_24	= 17,
+	RC_PROTO_RC6_6A_32	= 18,
+	RC_PROTO_RC6_MCE	= 19,
+	RC_PROTO_SHARP		= 20,
+	RC_PROTO_XMP		= 21,
+	RC_PROTO_CEC		= 22,
+	RC_PROTO_IMON		= 23,
+};
+
+#endif
diff --git a/tools/include/uapi/linux/seg6.h b/tools/include/uapi/linux/seg6.h
new file mode 100644
index 000000000000..286e8d6a8e98
--- /dev/null
+++ b/tools/include/uapi/linux/seg6.h
@@ -0,0 +1,55 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/*
+ *  SR-IPv6 implementation
+ *
+ *  Author:
+ *  David Lebrun <david.lebrun@uclouvain.be>
+ *
+ *
+ *  This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_LINUX_SEG6_H
+#define _UAPI_LINUX_SEG6_H
+
+#include <linux/types.h>
+#include <linux/in6.h>		/* For struct in6_addr. */
+
+/*
+ * SRH
+ */
+struct ipv6_sr_hdr {
+	__u8	nexthdr;
+	__u8	hdrlen;
+	__u8	type;
+	__u8	segments_left;
+	__u8	first_segment; /* Represents the last_entry field of SRH */
+	__u8	flags;
+	__u16	tag;
+
+	struct in6_addr segments[0];
+};
+
+#define SR6_FLAG1_PROTECTED	(1 << 6)
+#define SR6_FLAG1_OAM		(1 << 5)
+#define SR6_FLAG1_ALERT		(1 << 4)
+#define SR6_FLAG1_HMAC		(1 << 3)
+
+#define SR6_TLV_INGRESS		1
+#define SR6_TLV_EGRESS		2
+#define SR6_TLV_OPAQUE		3
+#define SR6_TLV_PADDING		4
+#define SR6_TLV_HMAC		5
+
+#define sr_has_hmac(srh) ((srh)->flags & SR6_FLAG1_HMAC)
+
+struct sr6_tlv {
+	__u8 type;
+	__u8 len;
+	__u8 data[0];
+};
+
+#endif
diff --git a/tools/include/uapi/linux/seg6_local.h b/tools/include/uapi/linux/seg6_local.h
new file mode 100644
index 000000000000..edc138bdc56d
--- /dev/null
+++ b/tools/include/uapi/linux/seg6_local.h
@@ -0,0 +1,80 @@
+/*
+ *  SR-IPv6 implementation
+ *
+ *  Author:
+ *  David Lebrun <david.lebrun@uclouvain.be>
+ *
+ *
+ *  This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _UAPI_LINUX_SEG6_LOCAL_H
+#define _UAPI_LINUX_SEG6_LOCAL_H
+
+#include <linux/seg6.h>
+
+enum {
+	SEG6_LOCAL_UNSPEC,
+	SEG6_LOCAL_ACTION,
+	SEG6_LOCAL_SRH,
+	SEG6_LOCAL_TABLE,
+	SEG6_LOCAL_NH4,
+	SEG6_LOCAL_NH6,
+	SEG6_LOCAL_IIF,
+	SEG6_LOCAL_OIF,
+	SEG6_LOCAL_BPF,
+	__SEG6_LOCAL_MAX,
+};
+#define SEG6_LOCAL_MAX (__SEG6_LOCAL_MAX - 1)
+
+enum {
+	SEG6_LOCAL_ACTION_UNSPEC	= 0,
+	/* node segment */
+	SEG6_LOCAL_ACTION_END		= 1,
+	/* adjacency segment (IPv6 cross-connect) */
+	SEG6_LOCAL_ACTION_END_X		= 2,
+	/* lookup of next seg NH in table */
+	SEG6_LOCAL_ACTION_END_T		= 3,
+	/* decap and L2 cross-connect */
+	SEG6_LOCAL_ACTION_END_DX2	= 4,
+	/* decap and IPv6 cross-connect */
+	SEG6_LOCAL_ACTION_END_DX6	= 5,
+	/* decap and IPv4 cross-connect */
+	SEG6_LOCAL_ACTION_END_DX4	= 6,
+	/* decap and lookup of DA in v6 table */
+	SEG6_LOCAL_ACTION_END_DT6	= 7,
+	/* decap and lookup of DA in v4 table */
+	SEG6_LOCAL_ACTION_END_DT4	= 8,
+	/* binding segment with insertion */
+	SEG6_LOCAL_ACTION_END_B6	= 9,
+	/* binding segment with encapsulation */
+	SEG6_LOCAL_ACTION_END_B6_ENCAP	= 10,
+	/* binding segment with MPLS encap */
+	SEG6_LOCAL_ACTION_END_BM	= 11,
+	/* lookup last seg in table */
+	SEG6_LOCAL_ACTION_END_S		= 12,
+	/* forward to SR-unaware VNF with static proxy */
+	SEG6_LOCAL_ACTION_END_AS	= 13,
+	/* forward to SR-unaware VNF with masquerading */
+	SEG6_LOCAL_ACTION_END_AM	= 14,
+	/* custom BPF action */
+	SEG6_LOCAL_ACTION_END_BPF	= 15,
+
+	__SEG6_LOCAL_ACTION_MAX,
+};
+
+#define SEG6_LOCAL_ACTION_MAX (__SEG6_LOCAL_ACTION_MAX - 1)
+
+enum {
+	SEG6_LOCAL_BPF_PROG_UNSPEC,
+	SEG6_LOCAL_BPF_PROG,
+	SEG6_LOCAL_BPF_PROG_NAME,
+	__SEG6_LOCAL_BPF_PROG_MAX,
+};
+
+#define SEG6_LOCAL_BPF_PROG_MAX (__SEG6_LOCAL_BPF_PROG_MAX - 1)
+
+#endif