With a relatively recent clang (7090c10273119) and with this commit to fix warnings in selftests (c8ed668593
) that uses __sink(err) to resolve unused variables. We get the following verifier error. root@6e731a24b33a:/host/tools/testing/selftests/bpf# ./test_sockmap libbpf: prog 'bpf_sockmap': BPF program load failed: Permission denied libbpf: prog 'bpf_sockmap': -- BEGIN PROG LOAD LOG -- 0: R1=ctx(off=0,imm=0) R10=fp0 ; op = (int) skops->op; 0: (61) r2 = *(u32 *)(r1 +0) ; R1=ctx(off=0,imm=0) R2_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) ; switch (op) { 1: (16) if w2 == 0x4 goto pc+5 ; R2_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) 2: (56) if w2 != 0x5 goto pc+15 ; R2_w=5 ; lport = skops->local_port; 3: (61) r2 = *(u32 *)(r1 +68) ; R1=ctx(off=0,imm=0) R2_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) ; if (lport == 10000) { 4: (56) if w2 != 0x2710 goto pc+13 18: R1=ctx(off=0,imm=0) R2=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) R10=fp0 ; __sink(err); 18: (bc) w1 = w0 R0 !read_ok processed 18 insns (limit 1000000) max_states_per_insn 0 total_states 2 peak_states 2 mark_read 1 -- END PROG LOAD LOG -- libbpf: prog 'bpf_sockmap': failed to load: -13 libbpf: failed to load object 'test_sockmap_kern.bpf.o' load_bpf_file: (-1) No such file or directory ERROR: (-1) load bpf failed libbpf: prog 'bpf_sockmap': BPF program load failed: Permission denied libbpf: prog 'bpf_sockmap': -- BEGIN PROG LOAD LOG -- 0: R1=ctx(off=0,imm=0) R10=fp0 ; op = (int) skops->op; 0: (61) r2 = *(u32 *)(r1 +0) ; R1=ctx(off=0,imm=0) R2_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) ; switch (op) { 1: (16) if w2 == 0x4 goto pc+5 ; R2_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) 2: (56) if w2 != 0x5 goto pc+15 ; R2_w=5 ; lport = skops->local_port; 3: (61) r2 = *(u32 *)(r1 +68) ; R1=ctx(off=0,imm=0) R2_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) ; if (lport == 10000) { 4: (56) if w2 != 0x2710 goto pc+13 18: R1=ctx(off=0,imm=0) R2=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) R10=fp0 ; __sink(err); 18: (bc) w1 = w0 R0 !read_ok processed 18 insns (limit 1000000) max_states_per_insn 0 total_states 2 peak_states 2 mark_read 1 -- END PROG LOAD LOG -- libbpf: prog 'bpf_sockmap': failed to load: -13 libbpf: failed to load object 'test_sockhash_kern.bpf.o' load_bpf_file: (-1) No such file or directory ERROR: (-1) load bpf failed libbpf: prog 'bpf_sockmap': BPF program load failed: Permission denied libbpf: prog 'bpf_sockmap': -- BEGIN PROG LOAD LOG -- 0: R1=ctx(off=0,imm=0) R10=fp0 ; op = (int) skops->op; 0: (61) r2 = *(u32 *)(r1 +0) ; R1=ctx(off=0,imm=0) R2_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) ; switch (op) { 1: (16) if w2 == 0x4 goto pc+5 ; R2_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) 2: (56) if w2 != 0x5 goto pc+15 ; R2_w=5 ; lport = skops->local_port; 3: (61) r2 = *(u32 *)(r1 +68) ; R1=ctx(off=0,imm=0) R2_w=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) ; if (lport == 10000) { 4: (56) if w2 != 0x2710 goto pc+13 18: R1=ctx(off=0,imm=0) R2=scalar(umax=4294967295,var_off=(0x0; 0xffffffff)) R10=fp0 ; __sink(err); 18: (bc) w1 = w0 R0 !read_ok processed 18 insns (limit 1000000) max_states_per_insn 0 total_states 2 peak_states 2 mark_read 1 -- END PROG LOAD LOG -- To fix simply remove the err value because its not actually used anywhere in the testing. We can investigate the root cause later. Future patch should probably actually test the err value as well. Although if the map updates fail they will get caught eventually by userspace. Fixes:c8ed668593
("selftests/bpf: fix lots of silly mistakes pointed out by compiler") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Link: https://lore.kernel.org/bpf/20230523025618.113937-15-john.fastabend@gmail.com
380 lines
8.7 KiB
C
380 lines
8.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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/* Copyright (c) 2017-2018 Covalent IO, Inc. http://covalent.io */
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#include <stddef.h>
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#include <string.h>
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#include <linux/bpf.h>
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#include <linux/if_ether.h>
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#include <linux/if_packet.h>
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#include <linux/ip.h>
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#include <linux/ipv6.h>
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#include <linux/in.h>
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#include <linux/udp.h>
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#include <linux/tcp.h>
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#include <linux/pkt_cls.h>
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#include <sys/socket.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_endian.h>
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#include "bpf_misc.h"
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/* Sockmap sample program connects a client and a backend together
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* using cgroups.
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*
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* client:X <---> frontend:80 client:X <---> backend:80
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*
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* For simplicity we hard code values here and bind 1:1. The hard
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* coded values are part of the setup in sockmap.sh script that
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* is associated with this BPF program.
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*
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* The bpf_printk is verbose and prints information as connections
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* are established and verdicts are decided.
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*/
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struct {
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__uint(type, TEST_MAP_TYPE);
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__uint(max_entries, 20);
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__uint(key_size, sizeof(int));
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__uint(value_size, sizeof(int));
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} sock_map SEC(".maps");
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struct {
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__uint(type, TEST_MAP_TYPE);
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__uint(max_entries, 20);
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__uint(key_size, sizeof(int));
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__uint(value_size, sizeof(int));
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} sock_map_txmsg SEC(".maps");
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struct {
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__uint(type, TEST_MAP_TYPE);
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__uint(max_entries, 20);
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__uint(key_size, sizeof(int));
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__uint(value_size, sizeof(int));
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} sock_map_redir SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__uint(max_entries, 1);
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__type(key, int);
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__type(value, int);
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} sock_apply_bytes SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__uint(max_entries, 1);
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__type(key, int);
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__type(value, int);
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} sock_cork_bytes SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__uint(max_entries, 6);
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__type(key, int);
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__type(value, int);
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} sock_bytes SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__uint(max_entries, 1);
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__type(key, int);
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__type(value, int);
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} sock_redir_flags SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__uint(max_entries, 3);
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__type(key, int);
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__type(value, int);
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} sock_skb_opts SEC(".maps");
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struct {
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__uint(type, TEST_MAP_TYPE);
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__uint(max_entries, 20);
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__uint(key_size, sizeof(int));
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__uint(value_size, sizeof(int));
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} tls_sock_map SEC(".maps");
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SEC("sk_skb1")
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int bpf_prog1(struct __sk_buff *skb)
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{
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int *f, two = 2;
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f = bpf_map_lookup_elem(&sock_skb_opts, &two);
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if (f && *f) {
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return *f;
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}
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return skb->len;
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}
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SEC("sk_skb2")
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int bpf_prog2(struct __sk_buff *skb)
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{
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__u32 lport = skb->local_port;
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__u32 rport = skb->remote_port;
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int len, *f, ret, zero = 0;
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__u64 flags = 0;
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__sink(rport);
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if (lport == 10000)
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ret = 10;
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else
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ret = 1;
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len = (__u32)skb->data_end - (__u32)skb->data;
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__sink(len);
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f = bpf_map_lookup_elem(&sock_skb_opts, &zero);
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if (f && *f) {
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ret = 3;
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flags = *f;
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}
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#ifdef SOCKMAP
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return bpf_sk_redirect_map(skb, &sock_map, ret, flags);
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#else
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return bpf_sk_redirect_hash(skb, &sock_map, &ret, flags);
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#endif
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}
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static inline void bpf_write_pass(struct __sk_buff *skb, int offset)
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{
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int err = bpf_skb_pull_data(skb, 6 + offset);
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void *data_end;
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char *c;
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if (err)
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return;
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c = (char *)(long)skb->data;
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data_end = (void *)(long)skb->data_end;
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if (c + 5 + offset < data_end)
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memcpy(c + offset, "PASS", 4);
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}
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SEC("sk_skb3")
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int bpf_prog3(struct __sk_buff *skb)
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{
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int err, *f, ret = SK_PASS;
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const int one = 1;
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f = bpf_map_lookup_elem(&sock_skb_opts, &one);
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if (f && *f) {
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__u64 flags = 0;
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ret = 0;
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flags = *f;
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err = bpf_skb_adjust_room(skb, -13, 0, 0);
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if (err)
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return SK_DROP;
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err = bpf_skb_adjust_room(skb, 4, 0, 0);
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if (err)
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return SK_DROP;
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bpf_write_pass(skb, 0);
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#ifdef SOCKMAP
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return bpf_sk_redirect_map(skb, &tls_sock_map, ret, flags);
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#else
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return bpf_sk_redirect_hash(skb, &tls_sock_map, &ret, flags);
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#endif
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}
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f = bpf_map_lookup_elem(&sock_skb_opts, &one);
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if (f && *f)
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ret = SK_DROP;
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err = bpf_skb_adjust_room(skb, 4, 0, 0);
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if (err)
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return SK_DROP;
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bpf_write_pass(skb, 13);
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return ret;
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}
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SEC("sockops")
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int bpf_sockmap(struct bpf_sock_ops *skops)
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{
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__u32 lport, rport;
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int op, ret;
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op = (int) skops->op;
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switch (op) {
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case BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB:
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lport = skops->local_port;
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rport = skops->remote_port;
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if (lport == 10000) {
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ret = 1;
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#ifdef SOCKMAP
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bpf_sock_map_update(skops, &sock_map, &ret,
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BPF_NOEXIST);
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#else
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bpf_sock_hash_update(skops, &sock_map, &ret,
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BPF_NOEXIST);
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#endif
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}
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break;
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case BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB:
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lport = skops->local_port;
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rport = skops->remote_port;
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if (bpf_ntohl(rport) == 10001) {
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ret = 10;
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#ifdef SOCKMAP
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bpf_sock_map_update(skops, &sock_map, &ret,
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BPF_NOEXIST);
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#else
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bpf_sock_hash_update(skops, &sock_map, &ret,
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BPF_NOEXIST);
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#endif
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}
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break;
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default:
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break;
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}
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return 0;
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}
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SEC("sk_msg1")
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int bpf_prog4(struct sk_msg_md *msg)
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{
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int *bytes, zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5;
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int *start, *end, *start_push, *end_push, *start_pop, *pop, err = 0;
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bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
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if (bytes)
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bpf_msg_apply_bytes(msg, *bytes);
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bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
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if (bytes)
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bpf_msg_cork_bytes(msg, *bytes);
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start = bpf_map_lookup_elem(&sock_bytes, &zero);
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end = bpf_map_lookup_elem(&sock_bytes, &one);
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if (start && end)
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bpf_msg_pull_data(msg, *start, *end, 0);
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start_push = bpf_map_lookup_elem(&sock_bytes, &two);
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end_push = bpf_map_lookup_elem(&sock_bytes, &three);
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if (start_push && end_push) {
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err = bpf_msg_push_data(msg, *start_push, *end_push, 0);
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if (err)
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return SK_DROP;
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}
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start_pop = bpf_map_lookup_elem(&sock_bytes, &four);
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pop = bpf_map_lookup_elem(&sock_bytes, &five);
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if (start_pop && pop)
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bpf_msg_pop_data(msg, *start_pop, *pop, 0);
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return SK_PASS;
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}
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SEC("sk_msg2")
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int bpf_prog6(struct sk_msg_md *msg)
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{
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int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5, key = 0;
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int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop, *f;
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int err = 0;
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__u64 flags = 0;
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bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
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if (bytes)
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bpf_msg_apply_bytes(msg, *bytes);
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bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
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if (bytes)
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bpf_msg_cork_bytes(msg, *bytes);
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start = bpf_map_lookup_elem(&sock_bytes, &zero);
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end = bpf_map_lookup_elem(&sock_bytes, &one);
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if (start && end)
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bpf_msg_pull_data(msg, *start, *end, 0);
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start_push = bpf_map_lookup_elem(&sock_bytes, &two);
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end_push = bpf_map_lookup_elem(&sock_bytes, &three);
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if (start_push && end_push) {
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err = bpf_msg_push_data(msg, *start_push, *end_push, 0);
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if (err)
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return SK_DROP;
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}
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start_pop = bpf_map_lookup_elem(&sock_bytes, &four);
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pop = bpf_map_lookup_elem(&sock_bytes, &five);
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if (start_pop && pop)
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bpf_msg_pop_data(msg, *start_pop, *pop, 0);
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f = bpf_map_lookup_elem(&sock_redir_flags, &zero);
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if (f && *f) {
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key = 2;
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flags = *f;
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}
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#ifdef SOCKMAP
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return bpf_msg_redirect_map(msg, &sock_map_redir, key, flags);
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#else
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return bpf_msg_redirect_hash(msg, &sock_map_redir, &key, flags);
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#endif
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}
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SEC("sk_msg3")
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int bpf_prog8(struct sk_msg_md *msg)
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{
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void *data_end = (void *)(long) msg->data_end;
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void *data = (void *)(long) msg->data;
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int ret = 0, *bytes, zero = 0;
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bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
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if (bytes) {
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ret = bpf_msg_apply_bytes(msg, *bytes);
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if (ret)
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return SK_DROP;
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} else {
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return SK_DROP;
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}
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__sink(data_end);
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__sink(data);
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return SK_PASS;
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}
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SEC("sk_msg4")
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int bpf_prog9(struct sk_msg_md *msg)
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{
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void *data_end = (void *)(long) msg->data_end;
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void *data = (void *)(long) msg->data;
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int ret = 0, *bytes, zero = 0;
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bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
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if (bytes) {
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if (((__u64)data_end - (__u64)data) >= *bytes)
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return SK_PASS;
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ret = bpf_msg_cork_bytes(msg, *bytes);
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if (ret)
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return SK_DROP;
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}
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return SK_PASS;
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}
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SEC("sk_msg5")
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int bpf_prog10(struct sk_msg_md *msg)
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{
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int *bytes, *start, *end, *start_push, *end_push, *start_pop, *pop;
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int zero = 0, one = 1, two = 2, three = 3, four = 4, five = 5, err = 0;
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bytes = bpf_map_lookup_elem(&sock_apply_bytes, &zero);
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if (bytes)
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bpf_msg_apply_bytes(msg, *bytes);
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bytes = bpf_map_lookup_elem(&sock_cork_bytes, &zero);
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if (bytes)
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bpf_msg_cork_bytes(msg, *bytes);
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start = bpf_map_lookup_elem(&sock_bytes, &zero);
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end = bpf_map_lookup_elem(&sock_bytes, &one);
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if (start && end)
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bpf_msg_pull_data(msg, *start, *end, 0);
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start_push = bpf_map_lookup_elem(&sock_bytes, &two);
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end_push = bpf_map_lookup_elem(&sock_bytes, &three);
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if (start_push && end_push) {
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err = bpf_msg_push_data(msg, *start_push, *end_push, 0);
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if (err)
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return SK_PASS;
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}
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start_pop = bpf_map_lookup_elem(&sock_bytes, &four);
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pop = bpf_map_lookup_elem(&sock_bytes, &five);
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if (start_pop && pop)
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bpf_msg_pop_data(msg, *start_pop, *pop, 0);
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return SK_DROP;
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}
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char _license[] SEC("license") = "GPL";
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