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

Alexei Starovoitov says:

====================
pull-request: bpf-next 2019-03-26

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) introduce bpf_tcp_check_syncookie() helper for XDP and tc, from Lorenz.

2) allow bpf_skb_ecn_set_ce() in tc, from Peter.

3) numerous bpf tc tunneling improvements, from Willem.

4) and other miscellaneous improvements from Adrian, Alan, Daniel, Ivan, Stanislav.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/bpf.h

@@ -205,6 +205,7 @@ enum bpf_return_type {
 	RET_PTR_TO_MAP_VALUE_OR_NULL,	/* returns a pointer to map elem value or NULL */
 	RET_PTR_TO_SOCKET_OR_NULL,	/* returns a pointer to a socket or NULL */
 	RET_PTR_TO_TCP_SOCK_OR_NULL,	/* returns a pointer to a tcp_sock or NULL */
+	RET_PTR_TO_SOCK_COMMON_OR_NULL,	/* returns a pointer to a sock_common or NULL */
 };
 
 /* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs

include/uapi/linux/bpf.h

@@ -1478,13 +1478,27 @@ union bpf_attr {
  * 		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:
+ *		There are two supported modes at this time:
+ *
+ *		* **BPF_ADJ_ROOM_MAC**: Adjust room at the mac layer
+ *		  (room space is added or removed below the layer 2 header).
  *
  * 		* **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.
+ *		The following flags are supported at this time:
+ *
+ *		* **BPF_F_ADJ_ROOM_FIXED_GSO**: Do not adjust gso_size.
+ *		  Adjusting mss in this way is not allowed for datagrams.
+ *
+ *		* **BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 **:
+ *		* **BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 **:
+ *		  Any new space is reserved to hold a tunnel header.
+ *		  Configure skb offsets and other fields accordingly.
+ *
+ *		* **BPF_F_ADJ_ROOM_ENCAP_L4_GRE **:
+ *		* **BPF_F_ADJ_ROOM_ENCAP_L4_UDP **:
+ *		  Use with ENCAP_L3 flags to further specify the tunnel type.
  *
  * 		A call to this helper is susceptible to change the underlaying
  * 		packet buffer. Therefore, at load time, all checks on pointers
@@ -2431,6 +2445,38 @@ union bpf_attr {
  *	Return
  *		A **struct bpf_sock** pointer on success, or **NULL** in
  *		case of failure.
+ *
+ * struct bpf_sock *bpf_skc_lookup_tcp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
+ *	Description
+ *		Look for TCP socket matching *tuple*, optionally in a child
+ *		network namespace *netns*. The return value must be checked,
+ *		and if non-**NULL**, released via **bpf_sk_release**\ ().
+ *
+ *		This function is identical to bpf_sk_lookup_tcp, except that it
+ *		also returns timewait or request sockets. Use bpf_sk_fullsock
+ *		or bpf_tcp_socket to access the full structure.
+ *
+ *		This helper is available only if the kernel was compiled with
+ *		**CONFIG_NET** configuration option.
+ *	Return
+ *		Pointer to **struct bpf_sock**, or **NULL** in case of failure.
+ *		For sockets with reuseport option, the **struct bpf_sock**
+ *		result is from **reuse->socks**\ [] using the hash of the tuple.
+ *
+ * int bpf_tcp_check_syncookie(struct bpf_sock *sk, void *iph, u32 iph_len, struct tcphdr *th, u32 th_len)
+ * 	Description
+ * 		Check whether iph and th contain a valid SYN cookie ACK for
+ * 		the listening socket in sk.
+ *
+ * 		iph points to the start of the IPv4 or IPv6 header, while
+ * 		iph_len contains sizeof(struct iphdr) or sizeof(struct ip6hdr).
+ *
+ * 		th points to the start of the TCP header, while th_len contains
+ * 		sizeof(struct tcphdr).
+ *
+ * 	Return
+ * 		0 if iph and th are a valid SYN cookie ACK, or a negative error
+ * 		otherwise.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -2531,7 +2577,9 @@ union bpf_attr {
 	FN(sk_fullsock),		\
 	FN(tcp_sock),			\
 	FN(skb_ecn_set_ce),		\
-	FN(get_listener_sock),
+	FN(get_listener_sock),		\
+	FN(skc_lookup_tcp),		\
+	FN(tcp_check_syncookie),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
@@ -2590,9 +2638,18 @@ enum bpf_func_id {
 /* Current network namespace */
 #define BPF_F_CURRENT_NETNS		(-1L)
 
+/* BPF_FUNC_skb_adjust_room flags. */
+#define BPF_F_ADJ_ROOM_FIXED_GSO	(1ULL << 0)
+
+#define BPF_F_ADJ_ROOM_ENCAP_L3_IPV4	(1ULL << 1)
+#define BPF_F_ADJ_ROOM_ENCAP_L3_IPV6	(1ULL << 2)
+#define BPF_F_ADJ_ROOM_ENCAP_L4_GRE	(1ULL << 3)
+#define BPF_F_ADJ_ROOM_ENCAP_L4_UDP	(1ULL << 4)
+
 /* Mode for BPF_FUNC_skb_adjust_room helper. */
 enum bpf_adj_room_mode {
 	BPF_ADJ_ROOM_NET,
+	BPF_ADJ_ROOM_MAC,
 };
 
 /* Mode for BPF_FUNC_skb_load_bytes_relative helper. */

kernel/bpf/verifier.c

@@ -369,7 +369,8 @@ static bool is_release_function(enum bpf_func_id func_id)
 static bool is_acquire_function(enum bpf_func_id func_id)
 {
 	return func_id == BPF_FUNC_sk_lookup_tcp ||
-		func_id == BPF_FUNC_sk_lookup_udp;
+		func_id == BPF_FUNC_sk_lookup_udp ||
+		func_id == BPF_FUNC_skc_lookup_tcp;
 }
 
 static bool is_ptr_cast_function(enum bpf_func_id func_id)
@@ -3147,19 +3148,11 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
 	} else if (fn->ret_type == RET_PTR_TO_SOCKET_OR_NULL) {
 		mark_reg_known_zero(env, regs, BPF_REG_0);
 		regs[BPF_REG_0].type = PTR_TO_SOCKET_OR_NULL;
-		if (is_acquire_function(func_id)) {
-			int id = acquire_reference_state(env, insn_idx);
-
-			if (id < 0)
-				return id;
-			/* For mark_ptr_or_null_reg() */
-			regs[BPF_REG_0].id = id;
-			/* For release_reference() */
-			regs[BPF_REG_0].ref_obj_id = id;
-		} else {
-			/* For mark_ptr_or_null_reg() */
-			regs[BPF_REG_0].id = ++env->id_gen;
-		}
+		regs[BPF_REG_0].id = ++env->id_gen;
+	} else if (fn->ret_type == RET_PTR_TO_SOCK_COMMON_OR_NULL) {
+		mark_reg_known_zero(env, regs, BPF_REG_0);
+		regs[BPF_REG_0].type = PTR_TO_SOCK_COMMON_OR_NULL;
+		regs[BPF_REG_0].id = ++env->id_gen;
 	} else if (fn->ret_type == RET_PTR_TO_TCP_SOCK_OR_NULL) {
 		mark_reg_known_zero(env, regs, BPF_REG_0);
 		regs[BPF_REG_0].type = PTR_TO_TCP_SOCK_OR_NULL;
@@ -3170,9 +3163,19 @@ static int check_helper_call(struct bpf_verifier_env *env, int func_id, int insn
 		return -EINVAL;
 	}
 
-	if (is_ptr_cast_function(func_id))
+	if (is_ptr_cast_function(func_id)) {
 		/* For release_reference() */
 		regs[BPF_REG_0].ref_obj_id = meta.ref_obj_id;
+	} else if (is_acquire_function(func_id)) {
+		int id = acquire_reference_state(env, insn_idx);
+
+		if (id < 0)
+			return id;
+		/* For mark_ptr_or_null_reg() */
+		regs[BPF_REG_0].id = id;
+		/* For release_reference() */
+		regs[BPF_REG_0].ref_obj_id = id;
+	}
 
 	do_refine_retval_range(regs, fn->ret_type, func_id, &meta);
 

samples/bpf/.gitignore

@@ -44,5 +44,6 @@ xdp_redirect_cpu
 xdp_redirect_map
 xdp_router_ipv4
 xdp_rxq_info
+xdp_sample_pkts
 xdp_tx_iptunnel
 xdpsock

tools/include/uapi/linux/bpf.h

@@ -1478,13 +1478,27 @@ union bpf_attr {
  * 		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:
+ *		There are two supported modes at this time:
+ *
+ *		* **BPF_ADJ_ROOM_MAC**: Adjust room at the mac layer
+ *		  (room space is added or removed below the layer 2 header).
  *
  * 		* **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.
+ *		The following flags are supported at this time:
+ *
+ *		* **BPF_F_ADJ_ROOM_FIXED_GSO**: Do not adjust gso_size.
+ *		  Adjusting mss in this way is not allowed for datagrams.
+ *
+ *		* **BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 **:
+ *		* **BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 **:
+ *		  Any new space is reserved to hold a tunnel header.
+ *		  Configure skb offsets and other fields accordingly.
+ *
+ *		* **BPF_F_ADJ_ROOM_ENCAP_L4_GRE **:
+ *		* **BPF_F_ADJ_ROOM_ENCAP_L4_UDP **:
+ *		  Use with ENCAP_L3 flags to further specify the tunnel type.
  *
  * 		A call to this helper is susceptible to change the underlaying
  * 		packet buffer. Therefore, at load time, all checks on pointers
@@ -2431,6 +2445,38 @@ union bpf_attr {
  *	Return
  *		A **struct bpf_sock** pointer on success, or **NULL** in
  *		case of failure.
+ *
+ * struct bpf_sock *bpf_skc_lookup_tcp(void *ctx, struct bpf_sock_tuple *tuple, u32 tuple_size, u64 netns, u64 flags)
+ *	Description
+ *		Look for TCP socket matching *tuple*, optionally in a child
+ *		network namespace *netns*. The return value must be checked,
+ *		and if non-**NULL**, released via **bpf_sk_release**\ ().
+ *
+ *		This function is identical to bpf_sk_lookup_tcp, except that it
+ *		also returns timewait or request sockets. Use bpf_sk_fullsock
+ *		or bpf_tcp_socket to access the full structure.
+ *
+ *		This helper is available only if the kernel was compiled with
+ *		**CONFIG_NET** configuration option.
+ *	Return
+ *		Pointer to **struct bpf_sock**, or **NULL** in case of failure.
+ *		For sockets with reuseport option, the **struct bpf_sock**
+ *		result is from **reuse->socks**\ [] using the hash of the tuple.
+ *
+ * int bpf_tcp_check_syncookie(struct bpf_sock *sk, void *iph, u32 iph_len, struct tcphdr *th, u32 th_len)
+ * 	Description
+ * 		Check whether iph and th contain a valid SYN cookie ACK for
+ * 		the listening socket in sk.
+ *
+ * 		iph points to the start of the IPv4 or IPv6 header, while
+ * 		iph_len contains sizeof(struct iphdr) or sizeof(struct ip6hdr).
+ *
+ * 		th points to the start of the TCP header, while th_len contains
+ * 		sizeof(struct tcphdr).
+ *
+ * 	Return
+ * 		0 if iph and th are a valid SYN cookie ACK, or a negative error
+ * 		otherwise.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -2531,7 +2577,9 @@ union bpf_attr {
 	FN(sk_fullsock),		\
 	FN(tcp_sock),			\
 	FN(skb_ecn_set_ce),		\
-	FN(get_listener_sock),
+	FN(get_listener_sock),		\
+	FN(skc_lookup_tcp),		\
+	FN(tcp_check_syncookie),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
@@ -2590,9 +2638,18 @@ enum bpf_func_id {
 /* Current network namespace */
 #define BPF_F_CURRENT_NETNS		(-1L)
 
+/* BPF_FUNC_skb_adjust_room flags. */
+#define BPF_F_ADJ_ROOM_FIXED_GSO	(1ULL << 0)
+
+#define BPF_F_ADJ_ROOM_ENCAP_L3_IPV4	(1ULL << 1)
+#define BPF_F_ADJ_ROOM_ENCAP_L3_IPV6	(1ULL << 2)
+#define BPF_F_ADJ_ROOM_ENCAP_L4_GRE	(1ULL << 3)
+#define BPF_F_ADJ_ROOM_ENCAP_L4_UDP	(1ULL << 4)
+
 /* Mode for BPF_FUNC_skb_adjust_room helper. */
 enum bpf_adj_room_mode {
 	BPF_ADJ_ROOM_NET,
+	BPF_ADJ_ROOM_MAC,
 };
 
 /* Mode for BPF_FUNC_skb_load_bytes_relative helper. */

tools/testing/selftests/bpf/.gitignore

@@ -30,4 +30,5 @@ test_netcnt
 test_section_names
 test_tcpnotify_user
 test_libbpf
+test_tcp_check_syncookie_user
 alu32

tools/testing/selftests/bpf/Makefile

@@ -51,7 +51,10 @@ TEST_PROGS := test_kmod.sh \
 	test_skb_cgroup_id.sh \
 	test_flow_dissector.sh \
 	test_xdp_vlan.sh \
-	test_lwt_ip_encap.sh
+	test_lwt_ip_encap.sh \
+	test_tcp_check_syncookie.sh \
+	test_tc_tunnel.sh \
+	test_tc_edt.sh
 
 TEST_PROGS_EXTENDED := with_addr.sh \
 	with_tunnels.sh \
@@ -60,7 +63,7 @@ TEST_PROGS_EXTENDED := with_addr.sh \
 
 # Compile but not part of 'make run_tests'
 TEST_GEN_PROGS_EXTENDED = test_libbpf_open test_sock_addr test_skb_cgroup_id_user \
-	flow_dissector_load test_flow_dissector
+	flow_dissector_load test_flow_dissector test_tcp_check_syncookie_user
 
 include ../lib.mk
 
@@ -69,7 +72,7 @@ TEST_CUSTOM_PROGS = $(OUTPUT)/urandom_read
 all: $(TEST_CUSTOM_PROGS)
 
 $(OUTPUT)/urandom_read: $(OUTPUT)/%: %.c
-	$(CC) -o $@ -static $< -Wl,--build-id
+	$(CC) -o $@ $< -Wl,--build-id
 
 BPFOBJ := $(OUTPUT)/libbpf.a
 

tools/testing/selftests/bpf/bpf_helpers.h

@@ -159,6 +159,11 @@ static struct bpf_sock *(*bpf_sk_lookup_tcp)(void *ctx,
 					     int size, unsigned long long netns_id,
 					     unsigned long long flags) =
 	(void *) BPF_FUNC_sk_lookup_tcp;
+static struct bpf_sock *(*bpf_skc_lookup_tcp)(void *ctx,
+					     struct bpf_sock_tuple *tuple,
+					     int size, unsigned long long netns_id,
+					     unsigned long long flags) =
+	(void *) BPF_FUNC_skc_lookup_tcp;
 static struct bpf_sock *(*bpf_sk_lookup_udp)(void *ctx,
 					     struct bpf_sock_tuple *tuple,
 					     int size, unsigned long long netns_id,
@@ -184,6 +189,9 @@ static struct bpf_sock *(*bpf_get_listener_sock)(struct bpf_sock *sk) =
 	(void *) BPF_FUNC_get_listener_sock;
 static int (*bpf_skb_ecn_set_ce)(void *ctx) =
 	(void *) BPF_FUNC_skb_ecn_set_ce;
+static int (*bpf_tcp_check_syncookie)(struct bpf_sock *sk,
+	    void *ip, int ip_len, void *tcp, int tcp_len) =
+	(void *) BPF_FUNC_tcp_check_syncookie;
 
 /* llvm builtin functions that eBPF C program may use to
  * emit BPF_LD_ABS and BPF_LD_IND instructions
@@ -274,6 +282,9 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
 #elif defined(__TARGET_ARCH_s930x)
 	#define bpf_target_s930x
 	#define bpf_target_defined
+#elif defined(__TARGET_ARCH_arm)
+	#define bpf_target_arm
+	#define bpf_target_defined
 #elif defined(__TARGET_ARCH_arm64)
 	#define bpf_target_arm64
 	#define bpf_target_defined
@@ -296,6 +307,8 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
 	#define bpf_target_x86
 #elif defined(__s390x__)
 	#define bpf_target_s930x
+#elif defined(__arm__)
+	#define bpf_target_arm
 #elif defined(__aarch64__)
 	#define bpf_target_arm64
 #elif defined(__mips__)
@@ -333,6 +346,19 @@ static int (*bpf_skb_adjust_room)(void *ctx, __s32 len_diff, __u32 mode,
 #define PT_REGS_SP(x) ((x)->gprs[15])
 #define PT_REGS_IP(x) ((x)->psw.addr)
 
+#elif defined(bpf_target_arm)
+
+#define PT_REGS_PARM1(x) ((x)->uregs[0])
+#define PT_REGS_PARM2(x) ((x)->uregs[1])
+#define PT_REGS_PARM3(x) ((x)->uregs[2])
+#define PT_REGS_PARM4(x) ((x)->uregs[3])
+#define PT_REGS_PARM5(x) ((x)->uregs[4])
+#define PT_REGS_RET(x) ((x)->uregs[14])
+#define PT_REGS_FP(x) ((x)->uregs[11]) /* Works only with CONFIG_FRAME_POINTER */
+#define PT_REGS_RC(x) ((x)->uregs[0])
+#define PT_REGS_SP(x) ((x)->uregs[13])
+#define PT_REGS_IP(x) ((x)->uregs[12])
+
 #elif defined(bpf_target_arm64)
 
 #define PT_REGS_PARM1(x) ((x)->regs[0])

tools/testing/selftests/bpf/config

@@ -23,3 +23,5 @@ CONFIG_LWTUNNEL=y
 CONFIG_BPF_STREAM_PARSER=y
 CONFIG_XDP_SOCKETS=y
 CONFIG_FTRACE_SYSCALLS=y
+CONFIG_IPV6_TUNNEL=y
+CONFIG_IPV6_GRE=y

tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c

 // SPDX-License-Identifier: GPL-2.0
 #include <test_progs.h>
 
+static __u64 read_perf_max_sample_freq(void)
+{
+	__u64 sample_freq = 5000; /* fallback to 5000 on error */
+	FILE *f;
+
+	f = fopen("/proc/sys/kernel/perf_event_max_sample_rate", "r");
+	if (f == NULL)
+		return sample_freq;
+	fscanf(f, "%llu", &sample_freq);
+	fclose(f);
+	return sample_freq;
+}
+
 void test_stacktrace_build_id_nmi(void)
 {
 	int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd;
 	const char *file = "./test_stacktrace_build_id.o";
 	int err, pmu_fd, prog_fd;
 	struct perf_event_attr attr = {
-		.sample_freq = 5000,
 		.freq = 1,
 		.type = PERF_TYPE_HARDWARE,
 		.config = PERF_COUNT_HW_CPU_CYCLES,
@@ -20,6 +32,8 @@ void test_stacktrace_build_id_nmi(void)
 	int build_id_matches = 0;
 	int retry = 1;
 
+	attr.sample_freq = read_perf_max_sample_freq();
+
 retry:
 	err = bpf_prog_load(file, BPF_PROG_TYPE_PERF_EVENT, &obj, &prog_fd);
 	if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno))

tools/testing/selftests/bpf/progs/test_tc_edt.c

+// SPDX-License-Identifier: GPL-2.0
+#include <stdint.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/pkt_cls.h>
+#include <linux/tcp.h>
+#include "bpf_helpers.h"
+#include "bpf_endian.h"
+
+/* the maximum delay we are willing to add (drop packets beyond that) */
+#define TIME_HORIZON_NS (2000 * 1000 * 1000)
+#define NS_PER_SEC 1000000000
+#define ECN_HORIZON_NS 5000000
+#define THROTTLE_RATE_BPS (5 * 1000 * 1000)
+
+/* flow_key => last_tstamp timestamp used */
+struct bpf_map_def SEC("maps") flow_map = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(uint32_t),
+	.value_size = sizeof(uint64_t),
+	.max_entries = 1,
+};
+
+static inline int throttle_flow(struct __sk_buff *skb)
+{
+	int key = 0;
+	uint64_t *last_tstamp = bpf_map_lookup_elem(&flow_map, &key);
+	uint64_t delay_ns = ((uint64_t)skb->len) * NS_PER_SEC /
+			THROTTLE_RATE_BPS;
+	uint64_t now = bpf_ktime_get_ns();
+	uint64_t tstamp, next_tstamp = 0;
+
+	if (last_tstamp)
+		next_tstamp = *last_tstamp + delay_ns;
+
+	tstamp = skb->tstamp;
+	if (tstamp < now)
+		tstamp = now;
+
+	/* should we throttle? */
+	if (next_tstamp <= tstamp) {
+		if (bpf_map_update_elem(&flow_map, &key, &tstamp, BPF_ANY))
+			return TC_ACT_SHOT;
+		return TC_ACT_OK;
+	}
+
+	/* do not queue past the time horizon */
+	if (next_tstamp - now >= TIME_HORIZON_NS)
+		return TC_ACT_SHOT;
+
+	/* set ecn bit, if needed */
+	if (next_tstamp - now >= ECN_HORIZON_NS)
+		bpf_skb_ecn_set_ce(skb);
+
+	if (bpf_map_update_elem(&flow_map, &key, &next_tstamp, BPF_EXIST))
+		return TC_ACT_SHOT;
+	skb->tstamp = next_tstamp;
+
+	return TC_ACT_OK;
+}
+
+static inline int handle_tcp(struct __sk_buff *skb, struct tcphdr *tcp)
+{
+	void *data_end = (void *)(long)skb->data_end;
+
+	/* drop malformed packets */
+	if ((void *)(tcp + 1) > data_end)
+		return TC_ACT_SHOT;
+
+	if (tcp->dest == bpf_htons(9000))
+		return throttle_flow(skb);
+
+	return TC_ACT_OK;
+}
+
+static inline int handle_ipv4(struct __sk_buff *skb)
+{
+	void *data_end = (void *)(long)skb->data_end;
+	void *data = (void *)(long)skb->data;
+	struct iphdr *iph;
+	uint32_t ihl;
+
+	/* drop malformed packets */
+	if (data + sizeof(struct ethhdr) > data_end)
+		return TC_ACT_SHOT;
+	iph = (struct iphdr *)(data + sizeof(struct ethhdr));
+	if ((void *)(iph + 1) > data_end)
+		return TC_ACT_SHOT;
+	ihl = iph->ihl * 4;
+	if (((void *)iph) + ihl > data_end)
+		return TC_ACT_SHOT;
+
+	if (iph->protocol == IPPROTO_TCP)
+		return handle_tcp(skb, (struct tcphdr *)(((void *)iph) + ihl));
+
+	return TC_ACT_OK;
+}
+
+SEC("cls_test") int tc_prog(struct __sk_buff *skb)
+{
+	if (skb->protocol == bpf_htons(ETH_P_IP))
+		return handle_ipv4(skb);
+
+	return TC_ACT_OK;
+}
+
+char __license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/progs/test_tc_tunnel.c

+// SPDX-License-Identifier: GPL-2.0
+
+/* In-place tunneling */
+
+#include <stdbool.h>
+#include <string.h>
+
+#include <linux/stddef.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/tcp.h>
+#include <linux/pkt_cls.h>
+#include <linux/types.h>
+
+#include "bpf_endian.h"
+#include "bpf_helpers.h"
+
+static const int cfg_port = 8000;
+
+struct grev4hdr {
+	struct iphdr ip;
+	__be16 flags;
+	__be16 protocol;
+} __attribute__((packed));
+
+struct grev6hdr {
+	struct ipv6hdr ip;
+	__be16 flags;
+	__be16 protocol;
+} __attribute__((packed));
+
+static __always_inline void set_ipv4_csum(struct iphdr *iph)
+{
+	__u16 *iph16 = (__u16 *)iph;
+	__u32 csum;
+	int i;
+
+	iph->check = 0;
+
+#pragma clang loop unroll(full)
+	for (i = 0, csum = 0; i < sizeof(*iph) >> 1; i++)
+		csum += *iph16++;
+
+	iph->check = ~((csum & 0xffff) + (csum >> 16));
+}
+
+static __always_inline int encap_ipv4(struct __sk_buff *skb, bool with_gre)
+{
+	struct grev4hdr h_outer;
+	struct iphdr iph_inner;
+	struct tcphdr tcph;
+	__u64 flags;
+	int olen;
+
+	if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_inner,
+			       sizeof(iph_inner)) < 0)
+		return TC_ACT_OK;
+
+	/* filter only packets we want */
+	if (iph_inner.ihl != 5 || iph_inner.protocol != IPPROTO_TCP)
+		return TC_ACT_OK;
+
+	if (bpf_skb_load_bytes(skb, ETH_HLEN + sizeof(iph_inner),
+			       &tcph, sizeof(tcph)) < 0)
+		return TC_ACT_OK;
+
+	if (tcph.dest != __bpf_constant_htons(cfg_port))
+		return TC_ACT_OK;
+
+	flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV4;
+	if (with_gre) {
+		flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE;
+		olen = sizeof(h_outer);
+	} else {
+		olen = sizeof(h_outer.ip);
+	}
+
+	/* add room between mac and network header */
+	if (bpf_skb_adjust_room(skb, olen, BPF_ADJ_ROOM_MAC, flags))
+		return TC_ACT_SHOT;
+
+	/* prepare new outer network header */
+	h_outer.ip = iph_inner;
+	h_outer.ip.tot_len = bpf_htons(olen +
+				      bpf_htons(h_outer.ip.tot_len));
+	if (with_gre) {
+		h_outer.ip.protocol = IPPROTO_GRE;
+		h_outer.protocol = bpf_htons(ETH_P_IP);
+		h_outer.flags = 0;
+	} else {
+		h_outer.ip.protocol = IPPROTO_IPIP;
+	}
+
+	set_ipv4_csum((void *)&h_outer.ip);
+
+	/* store new outer network header */
+	if (bpf_skb_store_bytes(skb, ETH_HLEN, &h_outer, olen,
+				BPF_F_INVALIDATE_HASH) < 0)
+		return TC_ACT_SHOT;
+
+	return TC_ACT_OK;
+}
+
+static __always_inline int encap_ipv6(struct __sk_buff *skb, bool with_gre)
+{
+	struct ipv6hdr iph_inner;
+	struct grev6hdr h_outer;
+	struct tcphdr tcph;
+	__u64 flags;
+	int olen;
+
+	if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_inner,
+			       sizeof(iph_inner)) < 0)
+		return TC_ACT_OK;
+
+	/* filter only packets we want */
+	if (bpf_skb_load_bytes(skb, ETH_HLEN + sizeof(iph_inner),
+			       &tcph, sizeof(tcph)) < 0)
+		return TC_ACT_OK;
+
+	if (tcph.dest != __bpf_constant_htons(cfg_port))
+		return TC_ACT_OK;
+
+	flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV6;
+	if (with_gre) {
+		flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE;
+		olen = sizeof(h_outer);
+	} else {
+		olen = sizeof(h_outer.ip);
+	}
+
+
+	/* add room between mac and network header */
+	if (bpf_skb_adjust_room(skb, olen, BPF_ADJ_ROOM_MAC, flags))
+		return TC_ACT_SHOT;
+
+	/* prepare new outer network header */
+	h_outer.ip = iph_inner;
+	h_outer.ip.payload_len = bpf_htons(olen +
+					   bpf_ntohs(h_outer.ip.payload_len));
+	if (with_gre) {
+		h_outer.ip.nexthdr = IPPROTO_GRE;
+		h_outer.protocol = bpf_htons(ETH_P_IPV6);
+		h_outer.flags = 0;
+	} else {
+		h_outer.ip.nexthdr = IPPROTO_IPV6;
+	}
+
+	/* store new outer network header */
+	if (bpf_skb_store_bytes(skb, ETH_HLEN, &h_outer, olen,
+				BPF_F_INVALIDATE_HASH) < 0)
+		return TC_ACT_SHOT;
+
+	return TC_ACT_OK;
+}
+
+SEC("encap_ipip")
+int __encap_ipip(struct __sk_buff *skb)
+{
+	if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+		return encap_ipv4(skb, false);
+	else
+		return TC_ACT_OK;
+}
+
+SEC("encap_gre")
+int __encap_gre(struct __sk_buff *skb)
+{
+	if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+		return encap_ipv4(skb, true);
+	else
+		return TC_ACT_OK;
+}
+
+SEC("encap_ip6tnl")
+int __encap_ip6tnl(struct __sk_buff *skb)
+{
+	if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+		return encap_ipv6(skb, false);
+	else
+		return TC_ACT_OK;
+}
+
+SEC("encap_ip6gre")
+int __encap_ip6gre(struct __sk_buff *skb)
+{
+	if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+		return encap_ipv6(skb, true);
+	else
+		return TC_ACT_OK;
+}
+
+static int decap_internal(struct __sk_buff *skb, int off, int len, char proto)
+{
+	char buf[sizeof(struct grev6hdr)];
+	int olen;
+
+	switch (proto) {
+	case IPPROTO_IPIP:
+	case IPPROTO_IPV6:
+		olen = len;
+		break;
+	case IPPROTO_GRE:
+		olen = len + 4 /* gre hdr */;
+		break;
+	default:
+		return TC_ACT_OK;
+	}
+
+	if (bpf_skb_adjust_room(skb, -olen, BPF_ADJ_ROOM_MAC,
+				BPF_F_ADJ_ROOM_FIXED_GSO))
+		return TC_ACT_SHOT;
+
+	return TC_ACT_OK;
+}
+
+static int decap_ipv4(struct __sk_buff *skb)
+{
+	struct iphdr iph_outer;
+
+	if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_outer,
+			       sizeof(iph_outer)) < 0)
+		return TC_ACT_OK;
+
+	if (iph_outer.ihl != 5)
+		return TC_ACT_OK;
+
+	return decap_internal(skb, ETH_HLEN, sizeof(iph_outer),
+			      iph_outer.protocol);
+}
+
+static int decap_ipv6(struct __sk_buff *skb)
+{
+	struct ipv6hdr iph_outer;
+
+	if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_outer,
+			       sizeof(iph_outer)) < 0)
+		return TC_ACT_OK;
+
+	return decap_internal(skb, ETH_HLEN, sizeof(iph_outer),
+			      iph_outer.nexthdr);
+}
+
+SEC("decap")
+int decap_f(struct __sk_buff *skb)
+{
+	switch (skb->protocol) {
+	case __bpf_constant_htons(ETH_P_IP):
+		return decap_ipv4(skb);
+	case __bpf_constant_htons(ETH_P_IPV6):
+		return decap_ipv6(skb);
+	default:
+		/* does not match, ignore */
+		return TC_ACT_OK;
+	}
+}
+
+char __license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/progs/test_tcp_check_syncookie_kern.c

+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Facebook
+// Copyright (c) 2019 Cloudflare
+
+#include <string.h>
+
+#include <linux/bpf.h>
+#include <linux/pkt_cls.h>
+#include <linux/if_ether.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <sys/socket.h>
+#include <linux/tcp.h>
+
+#include "bpf_helpers.h"
+#include "bpf_endian.h"
+
+struct bpf_map_def SEC("maps") results = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(__u64),
+	.max_entries = 1,
+};
+
+static __always_inline void check_syncookie(void *ctx, void *data,
+					    void *data_end)
+{
+	struct bpf_sock_tuple tup;
+	struct bpf_sock *sk;
+	struct ethhdr *ethh;
+	struct iphdr *ipv4h;
+	struct ipv6hdr *ipv6h;
+	struct tcphdr *tcph;
+	int ret;
+	__u32 key = 0;
+	__u64 value = 1;
+
+	ethh = data;
+	if (ethh + 1 > data_end)
+		return;
+
+	switch (bpf_ntohs(ethh->h_proto)) {
+	case ETH_P_IP:
+		ipv4h = data + sizeof(struct ethhdr);
+		if (ipv4h + 1 > data_end)
+			return;
+
+		if (ipv4h->ihl != 5)
+			return;
+
+		tcph = data + sizeof(struct ethhdr) + sizeof(struct iphdr);
+		if (tcph + 1 > data_end)
+			return;
+
+		tup.ipv4.saddr = ipv4h->saddr;
+		tup.ipv4.daddr = ipv4h->daddr;
+		tup.ipv4.sport = tcph->source;
+		tup.ipv4.dport = tcph->dest;
+
+		sk = bpf_skc_lookup_tcp(ctx, &tup, sizeof(tup.ipv4),
+					BPF_F_CURRENT_NETNS, 0);
+		if (!sk)
+			return;
+
+		if (sk->state != BPF_TCP_LISTEN)
+			goto release;
+
+		ret = bpf_tcp_check_syncookie(sk, ipv4h, sizeof(*ipv4h),
+					      tcph, sizeof(*tcph));
+		break;
+
+	case ETH_P_IPV6:
+		ipv6h = data + sizeof(struct ethhdr);
+		if (ipv6h + 1 > data_end)
+			return;
+
+		if (ipv6h->nexthdr != IPPROTO_TCP)
+			return;
+
+		tcph = data + sizeof(struct ethhdr) + sizeof(struct ipv6hdr);
+		if (tcph + 1 > data_end)
+			return;
+
+		memcpy(tup.ipv6.saddr, &ipv6h->saddr, sizeof(tup.ipv6.saddr));
+		memcpy(tup.ipv6.daddr, &ipv6h->daddr, sizeof(tup.ipv6.daddr));
+		tup.ipv6.sport = tcph->source;
+		tup.ipv6.dport = tcph->dest;
+
+		sk = bpf_skc_lookup_tcp(ctx, &tup, sizeof(tup.ipv6),
+					BPF_F_CURRENT_NETNS, 0);
+		if (!sk)
+			return;
+
+		if (sk->state != BPF_TCP_LISTEN)
+			goto release;
+
+		ret = bpf_tcp_check_syncookie(sk, ipv6h, sizeof(*ipv6h),
+					      tcph, sizeof(*tcph));
+		break;
+
+	default:
+		return;
+	}
+
+	if (ret == 0)
+		bpf_map_update_elem(&results, &key, &value, 0);
+
+release:
+	bpf_sk_release(sk);
+}
+
+SEC("clsact/check_syncookie")
+int check_syncookie_clsact(struct __sk_buff *skb)
+{
+	check_syncookie(skb, (void *)(long)skb->data,
+			(void *)(long)skb->data_end);
+	return TC_ACT_OK;
+}
+
+SEC("xdp/check_syncookie")
+int check_syncookie_xdp(struct xdp_md *ctx)
+{
+	check_syncookie(ctx, (void *)(long)ctx->data,
+			(void *)(long)ctx->data_end);
+	return XDP_PASS;
+}
+
+char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/test_tc_edt.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# This test installs a TC bpf program that throttles a TCP flow
+# with dst port = 9000 down to 5MBps. Then it measures actual
+# throughput of the flow.
+
+if [[ $EUID -ne 0 ]]; then
+	echo "This script must be run as root"
+	echo "FAIL"
+	exit 1
+fi
+
+# check that nc, dd, and timeout are present
+command -v nc >/dev/null 2>&1 || \
+	{ echo >&2 "nc is not available"; exit 1; }
+command -v dd >/dev/null 2>&1 || \
+	{ echo >&2 "nc is not available"; exit 1; }
+command -v timeout >/dev/null 2>&1 || \
+	{ echo >&2 "timeout is not available"; exit 1; }
+
+readonly NS_SRC="ns-src-$(mktemp -u XXXXXX)"
+readonly NS_DST="ns-dst-$(mktemp -u XXXXXX)"
+
+readonly IP_SRC="172.16.1.100"
+readonly IP_DST="172.16.2.100"
+
+cleanup()
+{
+	ip netns del ${NS_SRC}
+	ip netns del ${NS_DST}
+}
+
+trap cleanup EXIT
+
+set -e  # exit on error
+
+ip netns add "${NS_SRC}"
+ip netns add "${NS_DST}"
+ip link add veth_src type veth peer name veth_dst
+ip link set veth_src netns ${NS_SRC}
+ip link set veth_dst netns ${NS_DST}
+
+ip -netns ${NS_SRC} addr add ${IP_SRC}/24  dev veth_src
+ip -netns ${NS_DST} addr add ${IP_DST}/24  dev veth_dst
+
+ip -netns ${NS_SRC} link set dev veth_src up
+ip -netns ${NS_DST} link set dev veth_dst up
+
+ip -netns ${NS_SRC} route add ${IP_DST}/32  dev veth_src
+ip -netns ${NS_DST} route add ${IP_SRC}/32  dev veth_dst
+
+# set up TC on TX
+ip netns exec ${NS_SRC} tc qdisc add dev veth_src root fq
+ip netns exec ${NS_SRC} tc qdisc add dev veth_src clsact
+ip netns exec ${NS_SRC} tc filter add dev veth_src egress \
+	bpf da obj test_tc_edt.o sec cls_test
+
+
+# start the listener
+ip netns exec ${NS_DST} bash -c \
+	"nc -4 -l -s ${IP_DST} -p 9000 >/dev/null &"
+declare -i NC_PID=$!
+sleep 1
+
+declare -ir TIMEOUT=20
+declare -ir EXPECTED_BPS=5000000
+
+# run the load, capture RX bytes on DST
+declare -ir RX_BYTES_START=$( ip netns exec ${NS_DST} \
+	cat /sys/class/net/veth_dst/statistics/rx_bytes )
+
+set +e
+ip netns exec ${NS_SRC} bash -c "timeout ${TIMEOUT} dd if=/dev/zero \
+	bs=1000 count=1000000 > /dev/tcp/${IP_DST}/9000 2>/dev/null"
+set -e
+
+declare -ir RX_BYTES_END=$( ip netns exec ${NS_DST} \
+	cat /sys/class/net/veth_dst/statistics/rx_bytes )
+
+declare -ir ACTUAL_BPS=$(( ($RX_BYTES_END - $RX_BYTES_START) / $TIMEOUT ))
+
+echo $TIMEOUT $ACTUAL_BPS $EXPECTED_BPS | \
+	awk '{printf "elapsed: %d sec; bps difference: %.2f%%\n",
+		$1, ($2-$3)*100.0/$3}'
+
+# Pass the test if the actual bps is within 1% of the expected bps.
+# The difference is usually about 0.1% on a 20-sec test, and ==> zero
+# the longer the test runs.
+declare -ir RES=$( echo $ACTUAL_BPS $EXPECTED_BPS | \
+	 awk 'function abs(x){return ((x < 0.0) ? -x : x)}
+	      {if (abs(($1-$2)*100.0/$2) > 1.0) { print "1" }
+		else { print "0"} }' )
+if [ "${RES}" == "0" ] ; then
+	echo "PASS"
+else
+	echo "FAIL"
+	exit 1
+fi

tools/testing/selftests/bpf/test_tc_tunnel.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# In-place tunneling
+
+# must match the port that the bpf program filters on
+readonly port=8000
+
+readonly ns_prefix="ns-$$-"
+readonly ns1="${ns_prefix}1"
+readonly ns2="${ns_prefix}2"
+
+readonly ns1_v4=192.168.1.1
+readonly ns2_v4=192.168.1.2
+readonly ns1_v6=fd::1
+readonly ns2_v6=fd::2
+
+readonly infile="$(mktemp)"
+readonly outfile="$(mktemp)"
+
+setup() {
+	ip netns add "${ns1}"
+	ip netns add "${ns2}"
+
+	ip link add dev veth1 mtu 1500 netns "${ns1}" type veth \
+	      peer name veth2 mtu 1500 netns "${ns2}"
+
+	ip netns exec "${ns1}" ethtool -K veth1 tso off
+
+	ip -netns "${ns1}" link set veth1 up
+	ip -netns "${ns2}" link set veth2 up
+
+	ip -netns "${ns1}" -4 addr add "${ns1_v4}/24" dev veth1
+	ip -netns "${ns2}" -4 addr add "${ns2_v4}/24" dev veth2
+	ip -netns "${ns1}" -6 addr add "${ns1_v6}/64" dev veth1 nodad
+	ip -netns "${ns2}" -6 addr add "${ns2_v6}/64" dev veth2 nodad
+
+	# clamp route to reserve room for tunnel headers
+	ip -netns "${ns1}" -4 route flush table main
+	ip -netns "${ns1}" -6 route flush table main
+	ip -netns "${ns1}" -4 route add "${ns2_v4}" mtu 1476 dev veth1
+	ip -netns "${ns1}" -6 route add "${ns2_v6}" mtu 1456 dev veth1
+
+	sleep 1
+
+	dd if=/dev/urandom of="${infile}" bs="${datalen}" count=1 status=none
+}
+
+cleanup() {
+	ip netns del "${ns2}"
+	ip netns del "${ns1}"
+
+	if [[ -f "${outfile}" ]]; then
+		rm "${outfile}"
+	fi
+	if [[ -f "${infile}" ]]; then
+		rm "${infile}"
+	fi
+}
+
+server_listen() {
+	ip netns exec "${ns2}" nc "${netcat_opt}" -l -p "${port}" > "${outfile}" &
+	server_pid=$!
+	sleep 0.2
+}
+
+client_connect() {
+	ip netns exec "${ns1}" timeout 2 nc "${netcat_opt}" -w 1 "${addr2}" "${port}" < "${infile}"
+	echo $?
+}
+
+verify_data() {
+	wait "${server_pid}"
+	# sha1sum returns two fields [sha1] [filepath]
+	# convert to bash array and access first elem
+	insum=($(sha1sum ${infile}))
+	outsum=($(sha1sum ${outfile}))
+	if [[ "${insum[0]}" != "${outsum[0]}" ]]; then
+		echo "data mismatch"
+		exit 1
+	fi
+}
+
+set -e
+
+# no arguments: automated test, run all
+if [[ "$#" -eq "0" ]]; then
+	echo "ipip"
+	$0 ipv4 ipip 100
+
+	echo "ip6ip6"
+	$0 ipv6 ip6tnl 100
+
+	echo "ip gre"
+	$0 ipv4 gre 100
+
+	echo "ip6 gre"
+	$0 ipv6 ip6gre 100
+
+	echo "ip gre gso"
+	$0 ipv4 gre 2000
+
+	echo "ip6 gre gso"
+	$0 ipv6 ip6gre 2000
+
+	echo "OK. All tests passed"
+	exit 0
+fi
+
+if [[ "$#" -ne "3" ]]; then
+	echo "Usage: $0"
+	echo "   or: $0 <ipv4|ipv6> <tuntype> <data_len>"
+	exit 1
+fi
+
+case "$1" in
+"ipv4")
+	readonly addr1="${ns1_v4}"
+	readonly addr2="${ns2_v4}"
+	readonly netcat_opt=-4
+	;;
+"ipv6")
+	readonly addr1="${ns1_v6}"
+	readonly addr2="${ns2_v6}"
+	readonly netcat_opt=-6
+	;;
+*)
+	echo "unknown arg: $1"
+	exit 1
+	;;
+esac
+
+readonly tuntype=$2
+readonly datalen=$3
+
+echo "encap ${addr1} to ${addr2}, type ${tuntype}, len ${datalen}"
+
+trap cleanup EXIT
+
+setup
+
+# basic communication works
+echo "test basic connectivity"
+server_listen
+client_connect
+verify_data
+
+# clientside, insert bpf program to encap all TCP to port ${port}
+# client can no longer connect
+ip netns exec "${ns1}" tc qdisc add dev veth1 clsact
+ip netns exec "${ns1}" tc filter add dev veth1 egress \
+	bpf direct-action object-file ./test_tc_tunnel.o \
+	section "encap_${tuntype}"
+echo "test bpf encap without decap (expect failure)"
+server_listen
+! client_connect
+
+# serverside, insert decap module
+# server is still running
+# client can connect again
+ip netns exec "${ns2}" ip link add dev testtun0 type "${tuntype}" \
+	remote "${addr1}" local "${addr2}"
+# Because packets are decapped by the tunnel they arrive on testtun0 from
+# the IP stack perspective.  Ensure reverse path filtering is disabled
+# otherwise we drop the TCP SYN as arriving on testtun0 instead of the
+# expected veth2 (veth2 is where 192.168.1.2 is configured).
+ip netns exec "${ns2}" sysctl -qw net.ipv4.conf.all.rp_filter=0
+# rp needs to be disabled for both all and testtun0 as the rp value is
+# selected as the max of the "all" and device-specific values.
+ip netns exec "${ns2}" sysctl -qw net.ipv4.conf.testtun0.rp_filter=0
+ip netns exec "${ns2}" ip link set dev testtun0 up
+echo "test bpf encap with tunnel device decap"
+client_connect
+verify_data
+
+# serverside, use BPF for decap
+ip netns exec "${ns2}" ip link del dev testtun0
+ip netns exec "${ns2}" tc qdisc add dev veth2 clsact
+ip netns exec "${ns2}" tc filter add dev veth2 ingress \
+	bpf direct-action object-file ./test_tc_tunnel.o section decap
+server_listen
+echo "test bpf encap with bpf decap"
+client_connect
+verify_data
+
+echo OK

tools/testing/selftests/bpf/test_tcp_check_syncookie.sh

+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2018 Facebook
+# Copyright (c) 2019 Cloudflare
+
+set -eu
+
+wait_for_ip()
+{
+	local _i
+	printf "Wait for IP %s to become available " "$1"
+	for _i in $(seq ${MAX_PING_TRIES}); do
+		printf "."
+		if ns1_exec ping -c 1 -W 1 "$1" >/dev/null 2>&1; then
+			echo " OK"
+			return
+		fi
+		sleep 1
+	done
+	echo 1>&2 "ERROR: Timeout waiting for test IP to become available."
+	exit 1
+}
+
+get_prog_id()
+{
+	awk '/ id / {sub(/.* id /, "", $0); print($1)}'
+}
+
+ns1_exec()
+{
+	ip netns exec ns1 "$@"
+}
+
+setup()
+{
+	ip netns add ns1
+	ns1_exec ip link set lo up
+
+	ns1_exec sysctl -w net.ipv4.tcp_syncookies=2
+
+	wait_for_ip 127.0.0.1
+	wait_for_ip ::1
+}
+
+cleanup()
+{
+	ip netns del ns1 2>/dev/null || :
+}
+
+main()
+{
+	trap cleanup EXIT 2 3 6 15
+	setup
+
+	printf "Testing clsact..."
+	ns1_exec tc qdisc add dev "${TEST_IF}" clsact
+	ns1_exec tc filter add dev "${TEST_IF}" ingress \
+		bpf obj "${BPF_PROG_OBJ}" sec "${CLSACT_SECTION}" da
+
+	BPF_PROG_ID=$(ns1_exec tc filter show dev "${TEST_IF}" ingress | \
+		      get_prog_id)
+	ns1_exec "${PROG}" "${BPF_PROG_ID}"
+	ns1_exec tc qdisc del dev "${TEST_IF}" clsact
+
+	printf "Testing XDP..."
+	ns1_exec ip link set "${TEST_IF}" xdp \
+		object "${BPF_PROG_OBJ}" section "${XDP_SECTION}"
+	BPF_PROG_ID=$(ns1_exec ip link show "${TEST_IF}" | get_prog_id)
+	ns1_exec "${PROG}" "${BPF_PROG_ID}"
+}
+
+DIR=$(dirname $0)
+TEST_IF=lo
+MAX_PING_TRIES=5
+BPF_PROG_OBJ="${DIR}/test_tcp_check_syncookie_kern.o"
+CLSACT_SECTION="clsact/check_syncookie"
+XDP_SECTION="xdp/check_syncookie"
+BPF_PROG_ID=0
+PROG="${DIR}/test_tcp_check_syncookie_user"
+
+main

tools/testing/selftests/bpf/test_tcp_check_syncookie_user.c

+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Facebook
+// Copyright (c) 2019 Cloudflare
+
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <arpa/inet.h>
+#include <netinet/in.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#include "bpf_rlimit.h"
+#include "cgroup_helpers.h"
+
+static int start_server(const struct sockaddr *addr, socklen_t len)
+{
+	int fd;
+
+	fd = socket(addr->sa_family, SOCK_STREAM, 0);
+	if (fd == -1) {
+		log_err("Failed to create server socket");
+		goto out;
+	}
+
+	if (bind(fd, addr, len) == -1) {
+		log_err("Failed to bind server socket");
+		goto close_out;
+	}
+
+	if (listen(fd, 128) == -1) {
+		log_err("Failed to listen on server socket");
+		goto close_out;
+	}
+
+	goto out;
+
+close_out:
+	close(fd);
+	fd = -1;
+out:
+	return fd;
+}
+
+static int connect_to_server(int server_fd)
+{
+	struct sockaddr_storage addr;
+	socklen_t len = sizeof(addr);
+	int fd = -1;
+
+	if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
+		log_err("Failed to get server addr");
+		goto out;
+	}
+
+	fd = socket(addr.ss_family, SOCK_STREAM, 0);
+	if (fd == -1) {
+		log_err("Failed to create client socket");
+		goto out;
+	}
+
+	if (connect(fd, (const struct sockaddr *)&addr, len) == -1) {
+		log_err("Fail to connect to server");
+		goto close_out;
+	}
+
+	goto out;
+
+close_out:
+	close(fd);
+	fd = -1;
+out:
+	return fd;
+}
+
+static int get_map_fd_by_prog_id(int prog_id)
+{
+	struct bpf_prog_info info = {};
+	__u32 info_len = sizeof(info);
+	__u32 map_ids[1];
+	int prog_fd = -1;
+	int map_fd = -1;
+
+	prog_fd = bpf_prog_get_fd_by_id(prog_id);
+	if (prog_fd < 0) {
+		log_err("Failed to get fd by prog id %d", prog_id);
+		goto err;
+	}
+
+	info.nr_map_ids = 1;
+	info.map_ids = (__u64)(unsigned long)map_ids;
+
+	if (bpf_obj_get_info_by_fd(prog_fd, &info, &info_len)) {
+		log_err("Failed to get info by prog fd %d", prog_fd);
+		goto err;
+	}
+
+	if (!info.nr_map_ids) {
+		log_err("No maps found for prog fd %d", prog_fd);
+		goto err;
+	}
+
+	map_fd = bpf_map_get_fd_by_id(map_ids[0]);
+	if (map_fd < 0)
+		log_err("Failed to get fd by map id %d", map_ids[0]);
+err:
+	if (prog_fd >= 0)
+		close(prog_fd);
+	return map_fd;
+}
+
+static int run_test(int server_fd, int results_fd)
+{
+	int client = -1, srv_client = -1;
+	int ret = 0;
+	__u32 key = 0;
+	__u64 value = 0;
+
+	if (bpf_map_update_elem(results_fd, &key, &value, 0) < 0) {
+		log_err("Can't clear results");
+		goto err;
+	}
+
+	client = connect_to_server(server_fd);
+	if (client == -1)
+		goto err;
+
+	srv_client = accept(server_fd, NULL, 0);
+	if (srv_client == -1) {
+		log_err("Can't accept connection");
+		goto err;
+	}
+
+	if (bpf_map_lookup_elem(results_fd, &key, &value) < 0) {
+		log_err("Can't lookup result");
+		goto err;
+	}
+
+	if (value != 1) {
+		log_err("Didn't match syncookie: %llu", value);
+		goto err;
+	}
+
+	goto out;
+
+err:
+	ret = 1;
+out:
+	close(client);
+	close(srv_client);
+	return ret;
+}
+
+int main(int argc, char **argv)
+{
+	struct sockaddr_in addr4;
+	struct sockaddr_in6 addr6;
+	int server = -1;
+	int server_v6 = -1;
+	int results = -1;
+	int err = 0;
+
+	if (argc < 2) {
+		fprintf(stderr, "Usage: %s prog_id\n", argv[0]);
+		exit(1);
+	}
+
+	results = get_map_fd_by_prog_id(atoi(argv[1]));
+	if (results < 0) {
+		log_err("Can't get map");
+		goto err;
+	}
+
+	memset(&addr4, 0, sizeof(addr4));
+	addr4.sin_family = AF_INET;
+	addr4.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+	addr4.sin_port = 0;
+
+	memset(&addr6, 0, sizeof(addr6));
+	addr6.sin6_family = AF_INET6;
+	addr6.sin6_addr = in6addr_loopback;
+	addr6.sin6_port = 0;
+
+	server = start_server((const struct sockaddr *)&addr4, sizeof(addr4));
+	if (server == -1)
+		goto err;
+
+	server_v6 = start_server((const struct sockaddr *)&addr6,
+				 sizeof(addr6));
+	if (server_v6 == -1)
+		goto err;
+
+	if (run_test(server, results))
+		goto err;
+
+	if (run_test(server_v6, results))
+		goto err;
+
+	printf("ok\n");
+	goto out;
+err:
+	err = 1;
+out:
+	close(server);
+	close(server_v6);
+	close(results);
+	return err;
+}

tools/testing/selftests/bpf/test_verifier.c

@@ -198,7 +198,7 @@ static void bpf_fill_rand_ld_dw(struct bpf_test *self)
 }
 
 /* BPF_SK_LOOKUP contains 13 instructions, if you need to fix up maps */
-#define BPF_SK_LOOKUP							\
+#define BPF_SK_LOOKUP(func)						\
 	/* struct bpf_sock_tuple tuple = {} */				\
 	BPF_MOV64_IMM(BPF_REG_2, 0),					\
 	BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_2, -8),			\
@@ -207,13 +207,13 @@ static void bpf_fill_rand_ld_dw(struct bpf_test *self)
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -32),		\
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -40),		\
 	BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_2, -48),		\
-	/* sk = sk_lookup_tcp(ctx, &tuple, sizeof tuple, 0, 0) */	\
+	/* sk = func(ctx, &tuple, sizeof tuple, 0, 0) */		\
 	BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),				\
 	BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -48),				\
 	BPF_MOV64_IMM(BPF_REG_3, sizeof(struct bpf_sock_tuple)),	\
 	BPF_MOV64_IMM(BPF_REG_4, 0),					\
 	BPF_MOV64_IMM(BPF_REG_5, 0),					\
-	BPF_EMIT_CALL(BPF_FUNC_sk_lookup_tcp)
+	BPF_EMIT_CALL(BPF_FUNC_ ## func)
 
 /* BPF_DIRECT_PKT_R2 contains 7 instructions, it initializes default return
  * value into 0 and does necessary preparation for direct packet access

tools/testing/selftests/bpf/urandom_read.c

@@ -7,11 +7,19 @@
 
 #define BUF_SIZE 256
 
+static __attribute__((noinline))
+void urandom_read(int fd, int count)
+{
+       char buf[BUF_SIZE];
+       int i;
+
+       for (i = 0; i < count; ++i)
+               read(fd, buf, BUF_SIZE);
+}
+
 int main(int argc, char *argv[])
 {
 	int fd = open("/dev/urandom", O_RDONLY);
-	int i;
-	char buf[BUF_SIZE];
 	int count = 4;
 
 	if (fd < 0)
@@ -20,8 +28,7 @@ int main(int argc, char *argv[])
 	if (argc == 2)
 		count = atoi(argv[1]);
 
-	for (i = 0; i < count; ++i)
-		read(fd, buf, BUF_SIZE);
+	urandom_read(fd, count);
 
 	close(fd);
 	return 0;

tools/testing/selftests/bpf/verifier/unpriv.c

@@ -242,7 +242,7 @@
 	.insns = {
 	BPF_MOV64_REG(BPF_REG_8, BPF_REG_1),
 	/* struct bpf_sock *sock = bpf_sock_lookup(...); */
-	BPF_SK_LOOKUP,
+	BPF_SK_LOOKUP(sk_lookup_tcp),
 	BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
 	/* u64 foo; */
 	/* void *target = &foo; */
@@ -276,7 +276,7 @@
 	.insns = {
 	BPF_MOV64_REG(BPF_REG_8, BPF_REG_1),
 	/* struct bpf_sock *sock = bpf_sock_lookup(...); */
-	BPF_SK_LOOKUP,
+	BPF_SK_LOOKUP(sk_lookup_tcp),
 	BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
 	/* u64 foo; */
 	/* void *target = &foo; */
@@ -307,7 +307,7 @@
 	.insns = {
 	BPF_MOV64_REG(BPF_REG_8, BPF_REG_1),
 	/* struct bpf_sock *sock = bpf_sock_lookup(...); */
-	BPF_SK_LOOKUP,
+	BPF_SK_LOOKUP(sk_lookup_tcp),
 	BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
 	/* u64 foo; */
 	/* void *target = &foo; */
@@ -339,7 +339,7 @@
 	.insns = {
 	BPF_MOV64_REG(BPF_REG_8, BPF_REG_1),
 	/* struct bpf_sock *sock = bpf_sock_lookup(...); */
-	BPF_SK_LOOKUP,
+	BPF_SK_LOOKUP(sk_lookup_tcp),
 	BPF_MOV64_REG(BPF_REG_2, BPF_REG_0),
 	/* u64 foo; */
 	/* void *target = &foo; */