sync with latest libbpf repo

docs/kernel-versions.md

@@ -235,11 +235,13 @@ Helper | Kernel version | License | Commit |
 `BPF_FUNC_skb_under_cgroup()` | 4.8 | | [`4a482f34afcc`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=4a482f34afcc162d8456f449b137ec2a95be60d8)
 `BPF_FUNC_skb_vlan_pop()` | 4.3 | | [`4e10df9a60d9`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=4e10df9a60d96ced321dd2af71da558c6b750078)
 `BPF_FUNC_skb_vlan_push()` | 4.3 | | [`4e10df9a60d9`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=4e10df9a60d96ced321dd2af71da558c6b750078)
+`BPF_FUNC_skc_lookup_tcp()` | 5.2 | | [`edbf8c01de5a`](https://kernel.googlesource.com/pub/scm/linux/kernel/git/davem/net-next/+/edbf8c01de5a104a71ed6df2bf6421ceb2836a8e)
 `BPF_FUNC_sock_hash_update()` | 4.18 | | [`81110384441a`](https://git.kernel.org/cgit/linux/kernel/git/davem/net-next.git/commit/?id=81110384441a59cff47430f20f049e69b98c17f4)
 `BPF_FUNC_sock_map_update()` | 4.14 | | [`174a79ff9515`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=174a79ff9515f400b9a6115643dafd62a635b7e6)
 `BPF_FUNC_spin_lock()` | 5.1 | | [`d83525ca62cf`](https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit/?id=d83525ca62cf8ebe3271d14c36fb900c294274a2)
 `BPF_FUNC_spin_unlock()` | 5.1 | | [`d83525ca62cf`](https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit/?id=d83525ca62cf8ebe3271d14c36fb900c294274a2)
 `BPF_FUNC_tail_call()` | 4.2 | | [`04fd61ab36ec`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=04fd61ab36ec065e194ab5e74ae34a5240d992bb)
+`BPF_FUNC_tcp_check_syncookie()` | 5.2 | | [`399040847084`](https://kernel.googlesource.com/pub/scm/linux/kernel/git/davem/net-next/+/399040847084a69f345e0a52fd62f04654e0fce3)
 `BPF_FUNC_tcp_sock()` | 5.1 | | [`655a51e536c0`](https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/commit/?id=655a51e536c09d15ffa3603b1b6fce2b45b85a1f)
 `BPF_FUNC_trace_printk()` | 4.1 | GPL | [`9c959c863f82`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=9c959c863f8217a2ff3d7c296e8223654d240569)
 `BPF_FUNC_xdp_adjust_head()` | 4.10 | | [`17bedab27231`](https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=17bedab2723145d17b14084430743549e6943d03)

src/cc/compat/linux/virtual_bpf.h

@@ -106,6 +106,7 @@ enum bpf_cmd {
  BPF_BTF_GET_FD_BY_ID,
  BPF_TASK_FD_QUERY,
  BPF_MAP_LOOKUP_AND_DELETE_ELEM,
+ BPF_MAP_FREEZE,
 };
 
 enum bpf_map_type {
@@ -256,8 +257,19 @@ enum bpf_attach_type {
  */
 #define BPF_F_ANY_ALIGNMENT (1U << 1)
 
-/* when bpf_ldimm64->src_reg == BPF_PSEUDO_MAP_FD, bpf_ldimm64->imm == fd */
+/* When BPF ldimm64's insn[0].src_reg != 0 then this can have
+ * two extensions:
+ *
+ * insn[0].src_reg: BPF_PSEUDO_MAP_FD BPF_PSEUDO_MAP_VALUE
+ * insn[0].imm: map fd map fd
+ * insn[1].imm: 0 offset into value
+ * insn[0].off: 0 0
+ * insn[1].off: 0 0
+ * ldimm64 rewrite: address of map address of map[0]+offset
+ * verifier type: CONST_PTR_TO_MAP PTR_TO_MAP_VALUE
+ */
 #define BPF_PSEUDO_MAP_FD 1
+#define BPF_PSEUDO_MAP_VALUE 2
 
 /* when bpf_call->src_reg == BPF_PSEUDO_CALL, bpf_call->imm == pc-relative
  * offset to another bpf function
@@ -284,7 +296,7 @@ enum bpf_attach_type {
 
 #define BPF_OBJ_NAME_LEN 16U
 
-/* Flags for accessing BPF object */
+/* Flags for accessing BPF object from syscall side. */
 #define BPF_F_RDONLY (1U << 3)
 #define BPF_F_WRONLY (1U << 4)
 
@@ -294,6 +306,10 @@ enum bpf_attach_type {
 /* Zero-initialize hash function seed. This should only be used for testing. */
 #define BPF_F_ZERO_SEED (1U << 6)
 
+/* Flags for accessing BPF object from program side. */
+#define BPF_F_RDONLY_PROG (1U << 7)
+#define BPF_F_WRONLY_PROG (1U << 8)
+
 /* flags for BPF_PROG_QUERY */
 #define BPF_F_QUERY_EFFECTIVE (1U << 0)
 
@@ -397,6 +413,13 @@ union bpf_attr {
  __aligned_u64 data_out;
  __u32 repeat;
  __u32 duration;
+ __u32 ctx_size_in; /* input: len of ctx_in */
+ __u32 ctx_size_out; /* input/output: len of ctx_out
+ * returns ENOSPC if ctx_out
+ * is too small.
+ */
+ __aligned_u64 ctx_in;
+ __aligned_u64 ctx_out;
  } test;
 
  struct { /* anonymous struct used by BPF_*_GET_*_ID */
@@ -1479,13 +1502,27 @@ 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
@@ -2432,6 +2469,38 @@ 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), \
@@ -2532,7 +2601,9 @@ 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
@@ -2591,9 +2662,18 @@ 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. */

src/cc/export/helpers.h

@@ -341,10 +341,17 @@ static int (*bpf_skb_adjust_room)(void *ctx, int len_diff, u32 mode, u64 flags)
  (void *) BPF_FUNC_skb_adjust_room;
 static int (*bpf_skb_under_cgroup)(void *ctx, void *map, int index) =
  (void *) BPF_FUNC_skb_under_cgroup;
+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 int (*bpf_sk_redirect_map)(void *ctx, void *map, int key, int flags) =
  (void *) BPF_FUNC_sk_redirect_map;
 static int (*bpf_sock_map_update)(void *map, void *key, void *value, unsigned long long flags) =
  (void *) BPF_FUNC_sock_map_update;
+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;
 static int (*bpf_xdp_adjust_meta)(void *ctx, int offset) =
  (void *) BPF_FUNC_xdp_adjust_meta;
 

src/cc/libbpf.c

@@ -195,6 +195,8 @@ static struct bpf_helper helpers[] = {
  {"tcp_sock", "5.1"},
  {"skb_ecn_set_ce", "5.1"},
  {"get_listener_sock", "5.1"},
+ {"skc_lookup_tcp", "5.2"},
+ {"tcp_check_syncookie", "5.2"},
 };
 
 static uint64_t ptr_to_u64(void *ptr)