Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.sbin/tcpdump/privsep_pcap.c	Lines:	0	247	0.0 %
Date:	2017-11-13	Branches:	0	114	0.0 %


/*	$OpenBSD: privsep_pcap.c,v 1.22 2017/04/19 05:36:13 natano Exp $ */

/*
 * Copyright (c) 2004 Can Erkin Acar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *    - Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    - 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 COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "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
 * COPYRIGHT HOLDERS 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/types.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <net/if.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <pcap-int.h>
#include <pcap.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "privsep.h"

/*
 * privileged part of priv_pcap_setfilter, compile the filter
 * expression, and return it to the parent. Note that we fake an hpcap
 * and use it to capture the error messages, and pass the error back
 * to client.
 */
int
setfilter(int bpfd, int sock, char *filter)
{
	struct bpf_program fcode;
	int oflag, snap, link;
	u_int32_t netmask;
	pcap_t hpcap;

	must_read(sock, &oflag, sizeof(oflag));
	must_read(sock, &netmask, sizeof(netmask));
	must_read(sock, &snap, sizeof(snap));
	must_read(sock, &link, sizeof(link));

	if (snap < 0) {
		snprintf(hpcap.errbuf, PCAP_ERRBUF_SIZE, "invalid snaplen");
		goto err;
	}

	/* fake hpcap, it only needs errbuf, snaplen, and linktype to
	 * compile a filter expression */
	/* XXX messing with pcap internals */
	hpcap.snapshot = snap;
	hpcap.linktype = link;
	if (pcap_compile(&hpcap, &fcode, filter, oflag, netmask))
		goto err;

	/* if bpf descriptor is open, set the filter XXX check oflag? */
	if (bpfd >= 0 && ioctl(bpfd, BIOCSETF, &fcode)) {
		snprintf(hpcap.errbuf, PCAP_ERRBUF_SIZE,
		    "ioctl: BIOCSETF: %s", strerror(errno));
		pcap_freecode(&fcode);
		goto err;
	}
	if (fcode.bf_len > 0) {
		/* write the filter */
		must_write(sock, &fcode.bf_len, sizeof(fcode.bf_len));
		must_write(sock, fcode.bf_insns,
		    fcode.bf_len * sizeof(struct bpf_insn));
	} else {
		snprintf(hpcap.errbuf, PCAP_ERRBUF_SIZE, "Invalid filter size");
		pcap_freecode(&fcode);
		goto err;
	}


	pcap_freecode(&fcode);
	return (0);

 err:
	fcode.bf_len = 0;
	must_write(sock, &fcode.bf_len, sizeof(fcode.bf_len));

	/* write back the error string */
	write_string(sock, hpcap.errbuf);
	return (1);
}

/*
 * filter is compiled and set in the privileged process.
 * get the compiled output and set it locally for filtering dumps etc.
 */
struct bpf_program *
priv_pcap_setfilter(pcap_t *hpcap, int oflag, u_int32_t netmask)
{
	struct bpf_program *fcode = NULL;
	int snap, link;
	char *ebuf;

	if (priv_fd < 0)
		errx(1, "%s: called from privileged portion", __func__);

	ebuf = pcap_geterr(hpcap);
	snap = pcap_snapshot(hpcap);
	link = pcap_datalink(hpcap);

	fcode = calloc(1, sizeof(*fcode));
	if (fcode == NULL) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE, "out of memory");
		return (NULL);
	}

	write_command(priv_fd, PRIV_SETFILTER);

	/* send oflag, netmask, snaplen and linktype */
	must_write(priv_fd, &oflag, sizeof(oflag));
	must_write(priv_fd, &netmask, sizeof(netmask));
	must_write(priv_fd, &snap, sizeof(snap));
	must_write(priv_fd, &link, sizeof(link));

	/* receive compiled filter */
	must_read(priv_fd, &fcode->bf_len, sizeof(fcode->bf_len));
	if (fcode->bf_len <= 0) {
		int len;

		len = read_string(priv_fd, ebuf, PCAP_ERRBUF_SIZE, __func__);
		if (len == 0)
			snprintf(ebuf, PCAP_ERRBUF_SIZE, "pcap compile error");
		goto err;
	}

	fcode->bf_insns = calloc(fcode->bf_len, sizeof(struct bpf_insn));
	if (fcode->bf_insns == NULL) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE, "out of memory");
		goto err;
	}

	must_read(priv_fd, fcode->bf_insns,
	    fcode->bf_len * sizeof(struct bpf_insn));

	pcap_setfilter(hpcap, fcode);
	return (fcode);

 err:
	free(fcode);
	return (NULL);
}


/* privileged part of priv_pcap_live */
int
pcap_live(const char *device, int snaplen, int promisc, u_int dlt,
    u_int dirfilt)
{
	int		fd;
	struct ifreq	ifr;
	unsigned	v;

	if (device == NULL || snaplen <= 0)
		return (-1);

	if ((fd = open("/dev/bpf", O_RDONLY)) == -1)
		return (-1);

	v = 32768;	/* XXX this should be a user-accessible hook */
	ioctl(fd, BIOCSBLEN, &v);

	strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
	if (ioctl(fd, BIOCSETIF, &ifr) < 0)
		goto error;

	if (dlt != (u_int) -1 && ioctl(fd, BIOCSDLT, &dlt))
		goto error;

	if (promisc)
		/* this is allowed to fail */
		ioctl(fd, BIOCPROMISC, NULL);
	if (ioctl(fd, BIOCSDIRFILT, &dirfilt) < 0)
		goto error;

	/* lock the descriptor */
	if (ioctl(fd, BIOCLOCK, NULL) < 0)
		goto error;
	return (fd);

 error:
	close(fd);
	return (-1);
}


/*
 * XXX reimplement pcap_open_live with privsep, this is the
 * unprivileged part.
 */
pcap_t *
priv_pcap_live(const char *dev, int slen, int prom, int to_ms,
    char *ebuf, u_int dlt, u_int dirfilt)
{
	int fd, err;
	struct bpf_version bv;
	u_int v;
	pcap_t *p;

	if (priv_fd < 0)
		errx(1, "%s: called from privileged portion", __func__);

	if (dev == NULL) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE, "No interface specified");
		return (NULL);
	}

	p = malloc(sizeof(*p));
	if (p == NULL) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
		    pcap_strerror(errno));
		return (NULL);
	}

	bzero(p, sizeof(*p));

	write_command(priv_fd, PRIV_OPEN_BPF);
	must_write(priv_fd, &slen, sizeof(int));
	must_write(priv_fd, &prom, sizeof(int));
	must_write(priv_fd, &dlt, sizeof(u_int));
	must_write(priv_fd, &dirfilt, sizeof(u_int));
	write_string(priv_fd, dev);

	fd = receive_fd(priv_fd);
	must_read(priv_fd, &err, sizeof(int));
	if (fd < 0) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE,
		    "Failed to open bpf device for %s: %s",
		    dev, strerror(err));
		goto bad;
	}

	/* fd is locked, can only use 'safe' ioctls */
	if (ioctl(fd, BIOCVERSION, &bv) < 0) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE, "BIOCVERSION: %s",
		    pcap_strerror(errno));
		goto bad;
	}

	if (bv.bv_major != BPF_MAJOR_VERSION ||
	    bv.bv_minor < BPF_MINOR_VERSION) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE,
		    "kernel bpf filter out of date");
		goto bad;
	}

	p->fd = fd;
	p->snapshot = slen;

	/* Get the data link layer type. */
	if (ioctl(fd, BIOCGDLT, &v) < 0) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE, "BIOCGDLT: %s",
		    pcap_strerror(errno));
		goto bad;
	}
	p->linktype = v;

	/* XXX hack */
	if (p->linktype == DLT_PFLOG && p->snapshot < 160)
		p->snapshot = 160;

	/* set timeout */
	if (to_ms != 0) {
		struct timeval to;
		to.tv_sec = to_ms / 1000;
		to.tv_usec = (to_ms * 1000) % 1000000;
		if (ioctl(p->fd, BIOCSRTIMEOUT, &to) < 0) {
			snprintf(ebuf, PCAP_ERRBUF_SIZE, "BIOCSRTIMEOUT: %s",
			    pcap_strerror(errno));
			goto bad;
		}
	}

	if (ioctl(fd, BIOCGBLEN, &v) < 0) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE, "BIOCGBLEN: %s",
		    pcap_strerror(errno));
		goto bad;
	}
	p->bufsize = v;
	p->buffer = malloc(p->bufsize);
	if (p->buffer == NULL) {
		snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
		    pcap_strerror(errno));
		goto bad;
	}
	return (p);

 bad:
	if (fd >= 0)
		close(fd);
	free(p);
	return (NULL);
}



/*
 * reimplement pcap_open_offline with privsep, this is the
 * unprivileged part.
 * XXX merge with above?
 */
static void
swap_hdr(struct pcap_file_header *hp)
{
	hp->version_major = swap16(hp->version_major);
	hp->version_minor = swap16(hp->version_minor);
	hp->thiszone = swap32(hp->thiszone);
	hp->sigfigs = swap32(hp->sigfigs);
	hp->snaplen = swap32(hp->snaplen);
	hp->linktype = swap32(hp->linktype);
}

pcap_t *
priv_pcap_offline(const char *fname, char *errbuf)
{
	pcap_t *p;
	FILE *fp = NULL;
	struct pcap_file_header hdr;
	int linklen, err;

	if (priv_fd < 0)
		errx(1, "%s: called from privileged portion", __func__);

	p = malloc(sizeof(*p));
	if (p == NULL) {
		strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE);
		return (NULL);
	}

	memset((char *)p, 0, sizeof(*p));

	if (fname[0] == '-' && fname[1] == '\0') {
		p->fd = -1;
		fp = stdin;
	} else {
		write_command(priv_fd, PRIV_OPEN_DUMP);
		p->fd = receive_fd(priv_fd);
		must_read(priv_fd, &err, sizeof(int));
		if (p->fd < 0) {
			snprintf(errbuf, PCAP_ERRBUF_SIZE,
			    "Failed to open input file %s: %s",
			    fname, strerror(err));
			goto bad;
		}

		fp = fdopen(p->fd, "r");
		if (fp == NULL) {
			snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", fname,
			    pcap_strerror(errno));
			close(p->fd);
			p->fd = -1;
			goto bad;
		}
	}
	if (fread((char *)&hdr, sizeof(hdr), 1, fp) != 1) {
		snprintf(errbuf, PCAP_ERRBUF_SIZE, "fread: %s",
		    pcap_strerror(errno));
		goto bad;
	}

	if (hdr.magic != TCPDUMP_MAGIC) {
		if (swap32(hdr.magic) != TCPDUMP_MAGIC) {
			snprintf(errbuf, PCAP_ERRBUF_SIZE,
			    "bad dump file format");
			goto bad;
		}
		p->sf.swapped = 1;
		swap_hdr(&hdr);
	}
	if (hdr.version_major < PCAP_VERSION_MAJOR) {
		snprintf(errbuf, PCAP_ERRBUF_SIZE, "archaic file format");
		goto bad;
	}

	p->tzoff = hdr.thiszone;
	p->snapshot = hdr.snaplen;
	p->linktype = hdr.linktype;
	p->sf.rfile = fp;
	p->bufsize = hdr.snaplen;

	/* Align link header as required for proper data alignment */
	/* XXX should handle all types */
	switch (p->linktype) {

	case DLT_EN10MB:
		linklen = 14;
		break;

	case DLT_FDDI:
		linklen = 13 + 8;	/* fddi_header + llc */
		break;

	case DLT_NULL:
	default:
		linklen = 0;
		break;
	}

	if (p->bufsize < 0)
		p->bufsize = BPF_MAXBUFSIZE;
	p->sf.base = malloc(p->bufsize + BPF_ALIGNMENT);
	if (p->sf.base == NULL) {
		strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE);
		goto bad;
	}
	p->buffer = p->sf.base + BPF_ALIGNMENT - (linklen % BPF_ALIGNMENT);
	p->sf.version_major = hdr.version_major;
	p->sf.version_minor = hdr.version_minor;
#ifdef PCAP_FDDIPAD
	/* XXX what to do with this? */
	/* XXX padding only needed for kernel fcode */
	pcap_fddipad = 0;
#endif
	return (p);

 bad:
	if (fp != NULL && p->fd != -1)
		fclose(fp);
	free(p);
	return (NULL);
}


static int
sf_write_header(FILE *fp, int linktype, int thiszone, int snaplen)
{
	struct pcap_file_header hdr;

	bzero(&hdr, sizeof hdr);
	hdr.magic = TCPDUMP_MAGIC;
	hdr.version_major = PCAP_VERSION_MAJOR;
	hdr.version_minor = PCAP_VERSION_MINOR;

	hdr.thiszone = thiszone;
	hdr.snaplen = snaplen;
	hdr.sigfigs = 0;
	hdr.linktype = linktype;

	if (fwrite((char *)&hdr, sizeof(hdr), 1, fp) != 1)
		return (-1);

	return (0);
}

pcap_dumper_t *
priv_pcap_dump_open(pcap_t *p, char *fname)
{
	int fd, err;
	FILE *f;

	if (priv_fd < 0)
		errx(1, "%s: called from privileged portion", __func__);

	if (fname[0] == '-' && fname[1] == '\0') {
		f = stdout;
		priv_init_done();
	} else {
		write_command(priv_fd, PRIV_OPEN_OUTPUT);
		fd = receive_fd(priv_fd);
		must_read(priv_fd, &err, sizeof(err));
		if (fd < 0)  {
			snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
			    "Failed to open output file %s: %s",
			    fname, strerror(err));
			return (NULL);
		}
		f = fdopen(fd, "w");
		if (f == NULL) {
			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s: %s",
			    fname, pcap_strerror(errno));
			close(fd);
			return (NULL);
		}
	}

	(void)sf_write_header(f, p->linktype, p->tzoff, p->snapshot);
	return ((pcap_dumper_t *)f);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: privsep_pcap.c,v 1.22 2017/04/19 05:36:13 natano Exp $ */
2
3			/*
4			* Copyright (c) 2004 Can Erkin Acar
5			* All rights reserved.
6			*
7			* Redistribution and use in source and binary forms, with or without
8			* modification, are permitted provided that the following conditions
9			* are met:
10			*
11			* - Redistributions of source code must retain the above copyright
12			* notice, this list of conditions and the following disclaimer.
13			* - Redistributions in binary form must reproduce the above
14			* copyright notice, this list of conditions and the following
15			* disclaimer in the documentation and/or other materials provided
16			* with the distribution.
17			*
18			* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19			* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20			* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21			* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22			* COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23			* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24			* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25			* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
26			* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
28			* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29			* POSSIBILITY OF SUCH DAMAGE.
30			*/
31
32			#include <sys/types.h>
33			#include <sys/ioctl.h>
34			#include <sys/socket.h>
35			#include <net/if.h>
36
37			#include <err.h>
38			#include <errno.h>
39			#include <fcntl.h>
40			#include <pcap-int.h>
41			#include <pcap.h>
42			#include <stdio.h>
43			#include <stdlib.h>
44			#include <string.h>
45			#include <unistd.h>
46
47			#include "privsep.h"
48
49			/*
50			* privileged part of priv_pcap_setfilter, compile the filter
51			* expression, and return it to the parent. Note that we fake an hpcap
52			* and use it to capture the error messages, and pass the error back
53			* to client.
54			*/
55			int
56			setfilter(int bpfd, int sock, char *filter)
57			{
58			struct bpf_program fcode;
59			int oflag, snap, link;
60			u_int32_t netmask;
61			pcap_t hpcap;
62
63			must_read(sock, &oflag, sizeof(oflag));
64			must_read(sock, &netmask, sizeof(netmask));
65			must_read(sock, &snap, sizeof(snap));
66			must_read(sock, &link, sizeof(link));
67
68			if (snap < 0) {
69			snprintf(hpcap.errbuf, PCAP_ERRBUF_SIZE, "invalid snaplen");
70			goto err;
71			}
72
73			/* fake hpcap, it only needs errbuf, snaplen, and linktype to
74			* compile a filter expression */
75			/* XXX messing with pcap internals */
76			hpcap.snapshot = snap;
77			hpcap.linktype = link;
78			if (pcap_compile(&hpcap, &fcode, filter, oflag, netmask))
79			goto err;
80
81			/* if bpf descriptor is open, set the filter XXX check oflag? */
82			if (bpfd >= 0 && ioctl(bpfd, BIOCSETF, &fcode)) {
83			snprintf(hpcap.errbuf, PCAP_ERRBUF_SIZE,
84			"ioctl: BIOCSETF: %s", strerror(errno));
85			pcap_freecode(&fcode);
86			goto err;
87			}
88			if (fcode.bf_len > 0) {
89			/* write the filter */
90			must_write(sock, &fcode.bf_len, sizeof(fcode.bf_len));
91			must_write(sock, fcode.bf_insns,
92			fcode.bf_len * sizeof(struct bpf_insn));
93			} else {
94			snprintf(hpcap.errbuf, PCAP_ERRBUF_SIZE, "Invalid filter size");
95			pcap_freecode(&fcode);
96			goto err;
97			}
98
99
100			pcap_freecode(&fcode);
101			return (0);
102
103			err:
104			fcode.bf_len = 0;
105			must_write(sock, &fcode.bf_len, sizeof(fcode.bf_len));
106
107			/* write back the error string */
108			write_string(sock, hpcap.errbuf);
109			return (1);
110			}
111
112			/*
113			* filter is compiled and set in the privileged process.
114			* get the compiled output and set it locally for filtering dumps etc.
115			*/
116			struct bpf_program *
117			priv_pcap_setfilter(pcap_t *hpcap, int oflag, u_int32_t netmask)
118			{
119			struct bpf_program *fcode = NULL;
120			int snap, link;
121			char *ebuf;
122
123			if (priv_fd < 0)
124			errx(1, "%s: called from privileged portion", __func__);
125
126			ebuf = pcap_geterr(hpcap);
127			snap = pcap_snapshot(hpcap);
128			link = pcap_datalink(hpcap);
129
130			fcode = calloc(1, sizeof(*fcode));
131			if (fcode == NULL) {
132			snprintf(ebuf, PCAP_ERRBUF_SIZE, "out of memory");
133			return (NULL);
134			}
135
136			write_command(priv_fd, PRIV_SETFILTER);
137
138			/* send oflag, netmask, snaplen and linktype */
139			must_write(priv_fd, &oflag, sizeof(oflag));
140			must_write(priv_fd, &netmask, sizeof(netmask));
141			must_write(priv_fd, &snap, sizeof(snap));
142			must_write(priv_fd, &link, sizeof(link));
143
144			/* receive compiled filter */
145			must_read(priv_fd, &fcode->bf_len, sizeof(fcode->bf_len));
146			if (fcode->bf_len <= 0) {
147			int len;
148
149			len = read_string(priv_fd, ebuf, PCAP_ERRBUF_SIZE, __func__);
150			if (len == 0)
151			snprintf(ebuf, PCAP_ERRBUF_SIZE, "pcap compile error");
152			goto err;
153			}
154
155			fcode->bf_insns = calloc(fcode->bf_len, sizeof(struct bpf_insn));
156			if (fcode->bf_insns == NULL) {
157			snprintf(ebuf, PCAP_ERRBUF_SIZE, "out of memory");
158			goto err;
159			}
160
161			must_read(priv_fd, fcode->bf_insns,
162			fcode->bf_len * sizeof(struct bpf_insn));
163
164			pcap_setfilter(hpcap, fcode);
165			return (fcode);
166
167			err:
168			free(fcode);
169			return (NULL);
170			}
171
172
173			/* privileged part of priv_pcap_live */
174			int
175			pcap_live(const char *device, int snaplen, int promisc, u_int dlt,
176			u_int dirfilt)
177			{
178			int fd;
179			struct ifreq ifr;
180			unsigned v;
181
182			if (device == NULL \|\| snaplen <= 0)
183			return (-1);
184
185			if ((fd = open("/dev/bpf", O_RDONLY)) == -1)
186			return (-1);
187
188			v = 32768; /* XXX this should be a user-accessible hook */
189			ioctl(fd, BIOCSBLEN, &v);
190
191			strlcpy(ifr.ifr_name, device, sizeof(ifr.ifr_name));
192			if (ioctl(fd, BIOCSETIF, &ifr) < 0)
193			goto error;
194
195			if (dlt != (u_int) -1 && ioctl(fd, BIOCSDLT, &dlt))
196			goto error;
197
198			if (promisc)
199			/* this is allowed to fail */
200			ioctl(fd, BIOCPROMISC, NULL);
201			if (ioctl(fd, BIOCSDIRFILT, &dirfilt) < 0)
202			goto error;
203
204			/* lock the descriptor */
205			if (ioctl(fd, BIOCLOCK, NULL) < 0)
206			goto error;
207			return (fd);
208
209			error:
210			close(fd);
211			return (-1);
212			}
213
214
215			/*
216			* XXX reimplement pcap_open_live with privsep, this is the
217			* unprivileged part.
218			*/
219			pcap_t *
220			priv_pcap_live(const char *dev, int slen, int prom, int to_ms,
221			char *ebuf, u_int dlt, u_int dirfilt)
222			{
223			int fd, err;
224			struct bpf_version bv;
225			u_int v;
226			pcap_t *p;
227
228			if (priv_fd < 0)
229			errx(1, "%s: called from privileged portion", __func__);
230
231			if (dev == NULL) {
232			snprintf(ebuf, PCAP_ERRBUF_SIZE, "No interface specified");
233			return (NULL);
234			}
235
236			p = malloc(sizeof(*p));
237			if (p == NULL) {
238			snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
239			pcap_strerror(errno));
240			return (NULL);
241			}
242
243			bzero(p, sizeof(*p));
244
245			write_command(priv_fd, PRIV_OPEN_BPF);
246			must_write(priv_fd, &slen, sizeof(int));
247			must_write(priv_fd, &prom, sizeof(int));
248			must_write(priv_fd, &dlt, sizeof(u_int));
249			must_write(priv_fd, &dirfilt, sizeof(u_int));
250			write_string(priv_fd, dev);
251
252			fd = receive_fd(priv_fd);
253			must_read(priv_fd, &err, sizeof(int));
254			if (fd < 0) {
255			snprintf(ebuf, PCAP_ERRBUF_SIZE,
256			"Failed to open bpf device for %s: %s",
257			dev, strerror(err));
258			goto bad;
259			}
260
261			/* fd is locked, can only use 'safe' ioctls */
262			if (ioctl(fd, BIOCVERSION, &bv) < 0) {
263			snprintf(ebuf, PCAP_ERRBUF_SIZE, "BIOCVERSION: %s",
264			pcap_strerror(errno));
265			goto bad;
266			}
267
268			if (bv.bv_major != BPF_MAJOR_VERSION \|\|
269			bv.bv_minor < BPF_MINOR_VERSION) {
270			snprintf(ebuf, PCAP_ERRBUF_SIZE,
271			"kernel bpf filter out of date");
272			goto bad;
273			}
274
275			p->fd = fd;
276			p->snapshot = slen;
277
278			/* Get the data link layer type. */
279			if (ioctl(fd, BIOCGDLT, &v) < 0) {
280			snprintf(ebuf, PCAP_ERRBUF_SIZE, "BIOCGDLT: %s",
281			pcap_strerror(errno));
282			goto bad;
283			}
284			p->linktype = v;
285
286			/* XXX hack */
287			if (p->linktype == DLT_PFLOG && p->snapshot < 160)
288			p->snapshot = 160;
289
290			/* set timeout */
291			if (to_ms != 0) {
292			struct timeval to;
293			to.tv_sec = to_ms / 1000;
294			to.tv_usec = (to_ms * 1000) % 1000000;
295			if (ioctl(p->fd, BIOCSRTIMEOUT, &to) < 0) {
296			snprintf(ebuf, PCAP_ERRBUF_SIZE, "BIOCSRTIMEOUT: %s",
297			pcap_strerror(errno));
298			goto bad;
299			}
300			}
301
302			if (ioctl(fd, BIOCGBLEN, &v) < 0) {
303			snprintf(ebuf, PCAP_ERRBUF_SIZE, "BIOCGBLEN: %s",
304			pcap_strerror(errno));
305			goto bad;
306			}
307			p->bufsize = v;
308			p->buffer = malloc(p->bufsize);
309			if (p->buffer == NULL) {
310			snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc: %s",
311			pcap_strerror(errno));
312			goto bad;
313			}
314			return (p);
315
316			bad:
317			if (fd >= 0)
318			close(fd);
319			free(p);
320			return (NULL);
321			}
322
323
324
325			/*
326			* reimplement pcap_open_offline with privsep, this is the
327			* unprivileged part.
328			* XXX merge with above?
329			*/
330			static void
331			swap_hdr(struct pcap_file_header *hp)
332			{
333			hp->version_major = swap16(hp->version_major);
334			hp->version_minor = swap16(hp->version_minor);
335			hp->thiszone = swap32(hp->thiszone);
336			hp->sigfigs = swap32(hp->sigfigs);
337			hp->snaplen = swap32(hp->snaplen);
338			hp->linktype = swap32(hp->linktype);
339			}
340
341			pcap_t *
342			priv_pcap_offline(const char fname, char errbuf)
343			{
344			pcap_t *p;
345			FILE *fp = NULL;
346			struct pcap_file_header hdr;
347			int linklen, err;
348
349			if (priv_fd < 0)
350			errx(1, "%s: called from privileged portion", __func__);
351
352			p = malloc(sizeof(*p));
353			if (p == NULL) {
354			strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE);
355			return (NULL);
356			}
357
358			memset((char )p, 0, sizeof(p));
359
360			if (fname[0] == '-' && fname[1] == '\0') {
361			p->fd = -1;
362			fp = stdin;
363			} else {
364			write_command(priv_fd, PRIV_OPEN_DUMP);
365			p->fd = receive_fd(priv_fd);
366			must_read(priv_fd, &err, sizeof(int));
367			if (p->fd < 0) {
368			snprintf(errbuf, PCAP_ERRBUF_SIZE,
369			"Failed to open input file %s: %s",
370			fname, strerror(err));
371			goto bad;
372			}
373
374			fp = fdopen(p->fd, "r");
375			if (fp == NULL) {
376			snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", fname,
377			pcap_strerror(errno));
378			close(p->fd);
379			p->fd = -1;
380			goto bad;
381			}
382			}
383			if (fread((char *)&hdr, sizeof(hdr), 1, fp) != 1) {
384			snprintf(errbuf, PCAP_ERRBUF_SIZE, "fread: %s",
385			pcap_strerror(errno));
386			goto bad;
387			}
388
389			if (hdr.magic != TCPDUMP_MAGIC) {
390			if (swap32(hdr.magic) != TCPDUMP_MAGIC) {
391			snprintf(errbuf, PCAP_ERRBUF_SIZE,
392			"bad dump file format");
393			goto bad;
394			}
395			p->sf.swapped = 1;
396			swap_hdr(&hdr);
397			}
398			if (hdr.version_major < PCAP_VERSION_MAJOR) {
399			snprintf(errbuf, PCAP_ERRBUF_SIZE, "archaic file format");
400			goto bad;
401			}
402
403			p->tzoff = hdr.thiszone;
404			p->snapshot = hdr.snaplen;
405			p->linktype = hdr.linktype;
406			p->sf.rfile = fp;
407			p->bufsize = hdr.snaplen;
408
409			/* Align link header as required for proper data alignment */
410			/* XXX should handle all types */
411			switch (p->linktype) {
412
413			case DLT_EN10MB:
414			linklen = 14;
415			break;
416
417			case DLT_FDDI:
418			linklen = 13 + 8; /* fddi_header + llc */
419			break;
420
421			case DLT_NULL:
422			default:
423			linklen = 0;
424			break;
425			}
426
427			if (p->bufsize < 0)
428			p->bufsize = BPF_MAXBUFSIZE;
429			p->sf.base = malloc(p->bufsize + BPF_ALIGNMENT);
430			if (p->sf.base == NULL) {
431			strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE);
432			goto bad;
433			}
434			p->buffer = p->sf.base + BPF_ALIGNMENT - (linklen % BPF_ALIGNMENT);
435			p->sf.version_major = hdr.version_major;
436			p->sf.version_minor = hdr.version_minor;
437			#ifdef PCAP_FDDIPAD
438			/* XXX what to do with this? */
439			/* XXX padding only needed for kernel fcode */
440			pcap_fddipad = 0;
441			#endif
442			return (p);
443
444			bad:
445			if (fp != NULL && p->fd != -1)
446			fclose(fp);
447			free(p);
448			return (NULL);
449			}
450
451
452			static int
453			sf_write_header(FILE *fp, int linktype, int thiszone, int snaplen)
454			{
455			struct pcap_file_header hdr;
456
457			bzero(&hdr, sizeof hdr);
458			hdr.magic = TCPDUMP_MAGIC;
459			hdr.version_major = PCAP_VERSION_MAJOR;
460			hdr.version_minor = PCAP_VERSION_MINOR;
461
462			hdr.thiszone = thiszone;
463			hdr.snaplen = snaplen;
464			hdr.sigfigs = 0;
465			hdr.linktype = linktype;
466
467			if (fwrite((char *)&hdr, sizeof(hdr), 1, fp) != 1)
468			return (-1);
469
470			return (0);
471			}
472
473			pcap_dumper_t *
474			priv_pcap_dump_open(pcap_t p, char fname)
475			{
476			int fd, err;
477			FILE *f;
478
479			if (priv_fd < 0)
480			errx(1, "%s: called from privileged portion", __func__);
481
482			if (fname[0] == '-' && fname[1] == '\0') {
483			f = stdout;
484			priv_init_done();
485			} else {
486			write_command(priv_fd, PRIV_OPEN_OUTPUT);
487			fd = receive_fd(priv_fd);
488			must_read(priv_fd, &err, sizeof(err));
489			if (fd < 0) {
490			snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
491			"Failed to open output file %s: %s",
492			fname, strerror(err));
493			return (NULL);
494			}
495			f = fdopen(fd, "w");
496			if (f == NULL) {
497			snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s: %s",
498			fname, pcap_strerror(errno));
499			close(fd);
500			return (NULL);
501			}
502			}
503
504			(void)sf_write_header(f, p->linktype, p->tzoff, p->snapshot);
505			return ((pcap_dumper_t *)f);
506			}