xref: /src/tests/net/bpf/t_bpf.c

/*	$NetBSD: t_bpf.c,v 1.4 2012/01/13 16:28:44 christos Exp $	*/

/*-
 * Copyright (c) 2010 Antti Kantee.  All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/mbuf.h>
#include <sys/sysctl.h>
#include <sys/mman.h>
#include <unistd.h>

#include <net/if.h>
#include <net/bpf.h>

#include <fcntl.h>
#include <stdio.h>
#include <string.h>

#include <rump/rump.h>
#include <rump/rump_syscalls.h>

/* XXX: atf-c.h has collisions with mbuf */
#undef m_type
#undef m_data
#include <atf-c.h>

#include "../../h_macros.h"
#include "../config/netconfig.c"

ATF_TC(bpfwriteleak);
ATF_TC_HEAD(bpfwriteleak, tc)
{

	atf_tc_set_md_var(tc, "descr", "Checks that writing to /dev/bpf "
	    "does not leak mbufs");
}

static int
getmtdata(void)
{
	struct mbstat mbstat;
	size_t mbstatlen = sizeof(mbstat);
	const int mbstat_mib[] = { CTL_KERN, KERN_MBUF, MBUF_STATS };

	RL(rump_sys___sysctl(mbstat_mib, __arraycount(mbstat_mib),
	    &mbstat, &mbstatlen, NULL, 0));
	return mbstat.m_mtypes[MT_DATA];
}

ATF_TC_BODY(bpfwriteleak, tc)
{
	char buf[28]; /* sizeof(garbage) > etherhdrlen */
	struct ifreq ifr;
	int ifnum, bpfd;

	RZ(rump_init());
	RZ(rump_pub_shmif_create(NULL, &ifnum));
	sprintf(ifr.ifr_name, "shmif%d", ifnum);

	RL(bpfd = rump_sys_open("/dev/bpf", O_RDWR));
	RL(rump_sys_ioctl(bpfd, BIOCSETIF, &ifr));
	RL(rump_sys_ioctl(bpfd, BIOCSFEEDBACK, &ifr));

	if (getmtdata() != 0)
		atf_tc_fail("test precondition failed: MT_DATA mbufs != 0");

	ATF_REQUIRE_ERRNO(ENETDOWN, rump_sys_write(bpfd, buf, sizeof(buf))==-1);

	ATF_REQUIRE_EQ(getmtdata(), 0);
}

#if (SIZE_MAX > UINT_MAX)
ATF_TC(bpfwritetrunc);
ATF_TC_HEAD(bpfwritetrunc, tc)
{
	atf_tc_set_md_var(tc, "descr", "Checks that write to /dev/bpf "
	    "does not truncate size_t to int");
}

ATF_TC_BODY(bpfwritetrunc, tc)
{
	int bpfd;
	struct ifreq ifr;
	struct iovec *iov;
	size_t iovlen, sz;
	const size_t extra_bytes = 28;
	const size_t total = extra_bytes + UINT_MAX + 1;
	long iov_max, vm_page_size; /* round_page wants vm_page_size variable */

	memset(&ifr, 0, sizeof(ifr));

	iov_max      = sysconf(_SC_IOV_MAX);
	vm_page_size = sysconf(_SC_PAGE_SIZE);
	ATF_REQUIRE(iov_max > 1 && vm_page_size > 1);

	/* Minimize memory consumption by using many iovecs
	 * all pointing to one memory region */
	iov = calloc(iov_max, sizeof(struct iovec));
	ATF_REQUIRE(iov != NULL);

	sz = round_page((total + (iov_max - 1)) / iov_max);

	iov[0].iov_len = sz;
	iov[0].iov_base = mmap(NULL, sz, PROT_READ, MAP_ANON, -1, 0);
	ATF_REQUIRE(iov[0].iov_base != MAP_FAILED);

	iovlen = 1;
	while(sz + iov[0].iov_len <= total)
	{
		iov[iovlen].iov_len  = iov[0].iov_len;
		iov[iovlen].iov_base = iov[0].iov_base;
		sz += iov[0].iov_len;
		iovlen++;
	}

	if(sz < total)
	{
		iov[iovlen].iov_len = total - sz;
		iov[iovlen].iov_base = iov[0].iov_base;
		iovlen++;
	}

	/* Sanity checks */
	ATF_REQUIRE(iovlen >= 1 && iovlen <= (size_t)iov_max);
	ATF_REQUIRE_EQ(iov[iovlen-1].iov_len, total % iov[0].iov_len);

	RZ(rump_init());
	netcfg_rump_makeshmif("bpfwritetrunc", ifr.ifr_name);
	netcfg_rump_if(ifr.ifr_name, "10.1.1.1", "255.0.0.0");

	RL(bpfd = rump_sys_open("/dev/bpf", O_RDWR));
	RL(rump_sys_ioctl(bpfd, BIOCSETIF, &ifr));

	ATF_CHECK_ERRNO(EMSGSIZE, rump_sys_writev(bpfd, iov, iovlen) == -1);

	munmap(iov[0].iov_base, iov[0].iov_len);
	free(iov);
}
#endif /* #if (SIZE_MAX > UINT_MAX) */

ATF_TP_ADD_TCS(tp)
{

	ATF_TP_ADD_TC(tp, bpfwriteleak);
#if (SIZE_MAX > UINT_MAX)
	ATF_TP_ADD_TC(tp, bpfwritetrunc);
#endif
	return atf_no_error();
}