/* Copyright (c) 2015 PLUMgrid, http://plumgrid.com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 */
#include <linux/ptrace.h>
#include <linux/version.h>
#include <uapi/linux/bpf.h>
#include <uapi/linux/seccomp.h>
#include "bpf_helpers.h"

#define PROG(F) SEC("kprobe/"__stringify(F)) int bpf_func_##F

struct bpf_map_def SEC("maps") progs = {
	.type = BPF_MAP_TYPE_PROG_ARRAY,
	.key_size = sizeof(u32),
	.value_size = sizeof(u32),
	.max_entries = 1024,
};

SEC("kprobe/__seccomp_filter")
int bpf_prog1(struct pt_regs *ctx)
{
	int sc_nr = (int)PT_REGS_PARM1(ctx);

	/* dispatch into next BPF program depending on syscall number */
	bpf_tail_call(ctx, &progs, sc_nr);

	/* fall through -> unknown syscall */
	if (sc_nr >= __NR_getuid && sc_nr <= __NR_getsid) {
		char fmt[] = "syscall=%d (one of get/set uid/pid/gid)\n";
		bpf_trace_printk(fmt, sizeof(fmt), sc_nr);
	}
	return 0;
}

/* we jump here when syscall number == __NR_write */
PROG(__NR_write)(struct pt_regs *ctx)
{
	struct seccomp_data sd;

	bpf_probe_read(&sd, sizeof(sd), (void *)PT_REGS_PARM2(ctx));
	if (sd.args[2] == 512) {
		char fmt[] = "write(fd=%d, buf=%p, size=%d)\n";
		bpf_trace_printk(fmt, sizeof(fmt),
				 sd.args[0], sd.args[1], sd.args[2]);
	}
	return 0;
}

PROG(__NR_read)(struct pt_regs *ctx)
{
	struct seccomp_data sd;

	bpf_probe_read(&sd, sizeof(sd), (void *)PT_REGS_PARM2(ctx));
	if (sd.args[2] > 128 && sd.args[2] <= 1024) {
		char fmt[] = "read(fd=%d, buf=%p, size=%d)\n";
		bpf_trace_printk(fmt, sizeof(fmt),
				 sd.args[0], sd.args[1], sd.args[2]);
	}
	return 0;
}

PROG(__NR_mmap)(struct pt_regs *ctx)
{
	char fmt[] = "mmap\n";
	bpf_trace_printk(fmt, sizeof(fmt));
	return 0;
}

char _license[] SEC("license") = "GPL";
u32 _version SEC("version") = LINUX_VERSION_CODE;
i/linux/net-next.git/diff/net/xfrm?id=06425c308b92eaf60767bc71d359f4cbc7a561f8'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/net/xfrm'>
<input type='hidden' name='id' value='06425c308b92eaf60767bc71d359f4cbc7a561f8'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/log/?id=06425c308b92eaf60767bc71d359f4cbc7a561f8'>root</a>/<a href='/cgit.cgi/linux/net-next.git/log/net?id=06425c308b92eaf60767bc71d359f4cbc7a561f8'>net</a>/<a href='/cgit.cgi/linux/net-next.git/log/net/xfrm?id=06425c308b92eaf60767bc71d359f4cbc7a561f8'>xfrm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/net/xfrm?id=06425c308b92eaf60767bc71d359f4cbc7a561f8&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
include/trace/events?id=51964e9e12d0a054002a1a0d1dec4f661c7aaf28&amp;showmsg=1'>events</a>/<a href='/cgit.cgi/linux/net-next.git/log/include/trace/events/asoc.h?id=51964e9e12d0a054002a1a0d1dec4f661c7aaf28&amp;showmsg=1'>asoc.h</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/include/trace/events/asoc.h?id=51964e9e12d0a054002a1a0d1dec4f661c7aaf28'>Collapse</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>