34 lines
700 B
C
34 lines
700 B
C
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#include <linux/bpf.h>
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#include "bpf_helpers.h"
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#include "bpf_util.h"
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#include "bpf_endian.h"
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int _version SEC("version") = 1;
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#define bpf_printk(fmt, ...) \
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({ \
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char ____fmt[] = fmt; \
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bpf_trace_printk(____fmt, sizeof(____fmt), \
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##__VA_ARGS__); \
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})
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SEC("sk_msg1")
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int bpf_prog1(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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char *d;
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if (data + 8 > data_end)
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return SK_DROP;
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bpf_printk("data length %i\n", (__u64)msg->data_end - (__u64)msg->data);
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d = (char *)data;
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bpf_printk("hello sendmsg hook %i %i\n", d[0], d[1]);
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return SK_PASS;
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}
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char _license[] SEC("license") = "GPL";
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