samples/bpf: replace BPF programs header with net_shared.h

This commit applies "net_shared.h" to BPF programs to remove existing
network related header dependencies. Also, this commit removes
unnecessary headers before applying "vmlinux.h" to the BPF programs.

Mostly, endianness conversion function has been applied to the source.
In addition, several macros have been defined to fulfill the INET,
TC-related constants.

Signed-off-by: Daniel T. Lee <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexei Starovoitov <[email protected]>

Author: DanielTimLee

samples/bpf/net_shared.h

@@ -2,6 +2,9 @@
 #ifndef _NET_SHARED_H
 #define _NET_SHARED_H
 
+#define AF_INET		2
+#define AF_INET6	10
+
 #define ETH_ALEN 6
 #define ETH_P_802_3_MIN 0x0600
 #define ETH_P_8021Q 0x8100
@@ -11,6 +14,9 @@
 #define ETH_P_ARP 0x0806
 #define IPPROTO_ICMPV6 58
 
+#define TC_ACT_OK		0
+#define TC_ACT_SHOT		2
+
 #if defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && \
 	__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 #define bpf_ntohs(x)		__builtin_bswap16(x)

samples/bpf/sock_flags_kern.c

@@ -1,5 +1,5 @@
+#include "net_shared.h"
 #include <uapi/linux/bpf.h>
-#include <linux/socket.h>
 #include <linux/net.h>
 #include <uapi/linux/in.h>
 #include <uapi/linux/in6.h>
@@ -17,10 +17,10 @@ int bpf_prog1(struct bpf_sock *sk)
 	bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol);
 	bpf_trace_printk(fmt2, sizeof(fmt2), uid, gid);
 
-	/* block PF_INET6, SOCK_DGRAM, IPPROTO_ICMPV6 sockets
+	/* block AF_INET6, SOCK_DGRAM, IPPROTO_ICMPV6 sockets
 	 * ie., make ping6 fail
 	 */
-	if (sk->family == PF_INET6 &&
+	if (sk->family == AF_INET6 &&
 	    sk->type == SOCK_DGRAM   &&
 	    sk->protocol == IPPROTO_ICMPV6)
 		return 0;
@@ -35,10 +35,10 @@ int bpf_prog2(struct bpf_sock *sk)
 
 	bpf_trace_printk(fmt, sizeof(fmt), sk->family, sk->type, sk->protocol);
 
-	/* block PF_INET, SOCK_DGRAM, IPPROTO_ICMP sockets
+	/* block AF_INET, SOCK_DGRAM, IPPROTO_ICMP sockets
 	 * ie., make ping fail
 	 */
-	if (sk->family == PF_INET &&
+	if (sk->family == AF_INET &&
 	    sk->type == SOCK_DGRAM  &&
 	    sk->protocol == IPPROTO_ICMP)
 		return 0;

samples/bpf/test_cgrp2_tc_kern.c

@@ -5,10 +5,8 @@
  * License as published by the Free Software Foundation.
  */
 #define KBUILD_MODNAME "foo"
-#include <uapi/linux/if_ether.h>
-#include <uapi/linux/in6.h>
+#include "net_shared.h"
 #include <uapi/linux/ipv6.h>
-#include <uapi/linux/pkt_cls.h>
 #include <uapi/linux/bpf.h>
 #include <bpf/bpf_helpers.h>
 
@@ -42,7 +40,7 @@ int handle_egress(struct __sk_buff *skb)
 	if (data + sizeof(*eth) + sizeof(*ip6h) > data_end)
 		return TC_ACT_OK;
 
-	if (eth->h_proto != htons(ETH_P_IPV6) ||
+	if (eth->h_proto != bpf_htons(ETH_P_IPV6) ||
 	    ip6h->nexthdr != IPPROTO_ICMPV6) {
 		bpf_trace_printk(dont_care_msg, sizeof(dont_care_msg),
 				 eth->h_proto, ip6h->nexthdr);

samples/bpf/test_lwt_bpf.c

@@ -10,6 +10,7 @@
  * General Public License for more details.
  */
 
+#include "net_shared.h"
 #include <stdint.h>
 #include <stddef.h>
 #include <linux/bpf.h>
@@ -176,7 +177,7 @@ static inline int __do_push_ll_and_redirect(struct __sk_buff *skb)
 		printk("skb_change_head() failed: %d", ret);
 	}
 
-	ehdr.h_proto = __constant_htons(ETH_P_IP);
+	ehdr.h_proto = bpf_htons(ETH_P_IP);
 	memcpy(&ehdr.h_source, &smac, 6);
 	memcpy(&ehdr.h_dest, &dmac, 6);