1 files changed, 268 insertions, 0 deletions
diff --git a/tests/sys/net/bpf/pcap-test.c b/tests/sys/net/bpf/pcap-test.c
new file mode 100644
index 000000000000..9d01548f7aae
--- /dev/null
+++ b/tests/sys/net/bpf/pcap-test.c
@@ -0,0 +1,268 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2025 Gleb Smirnoff <glebius@FreeBSD.org>
+ *
+ * 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 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 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/queue.h>
+#include <netinet/ip.h>
+#include <pcap/pcap.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <err.h>
+
+static int
+strtolerr(const char *s)
+{
+	int rv;
+
+	if ((rv = (int)strtol(s, NULL, 10)) < 1)
+		errx(1, "bad count %s", s);
+	return (rv);
+}
+
+static pcap_direction_t
+strtodir(const char *s)
+{
+	static const struct dirstr {
+		const char *str;
+		pcap_direction_t dir;
+	} dirs[] = {
+		{ "in", PCAP_D_IN },
+		{ "out", PCAP_D_OUT },
+		{ "both", PCAP_D_INOUT },
+		{ "inout", PCAP_D_INOUT },
+	};
+
+	for (u_int i = 0; i < nitems(dirs); i++)
+		if (strcasecmp(s, dirs[i].str) == 0)
+			return (dirs[i].dir);
+	errx(1, "bad directions %s", s);
+}
+
+static char errbuf[PCAP_ERRBUF_SIZE];
+
+static pcap_t *
+pcap_open(const char *name, pcap_direction_t dir)
+{
+	pcap_t *p;
+
+	if ((p = pcap_create(name, errbuf)) == NULL)
+		errx(1, "pcap_create: %s", errbuf);
+	if (pcap_set_timeout(p, 10) != 0)
+		errx(1, "pcap_set_timeout: %s", pcap_geterr(p));
+	if (pcap_activate(p) != 0)
+		errx(1, "pcap_activate: %s", errbuf);
+	if (pcap_setdirection(p, dir) != 0)
+		errx(1, "pcap_setdirection: %s", pcap_geterr(p));
+	return (p);
+}
+
+#if 0
+/*
+ * Deal with the FreeBSD writer only optimization hack in bpf(4).
+ * Needed only when net.bpf.optimize_writers=1.
+ */
+static pcap_t *
+pcap_rwopen(const char *name, pcap_direction_t dir)
+{
+	pcap_t *p;
+	struct bpf_program fp;
+
+	p = pcap_open(name, dir);
+	if (pcap_compile(p, &fp, "", 0, PCAP_NETMASK_UNKNOWN) != 0)
+		errx(1, "pcap_compile: %s", pcap_geterr(p));
+	if (pcap_setfilter(p, &fp) != 0)
+		errx(1, "pcap_setfilter: %s", pcap_geterr(p));
+	pcap_freecode(&fp);
+	return (p);
+}
+#endif
+
+static void
+list(int argc __unused, char *argv[] __unused)
+{
+	pcap_if_t *all, *p;
+
+	if (pcap_findalldevs(&all, errbuf) != 0)
+		errx(1, "pcap_findalldevs: %s", errbuf);
+	for (p = all; p != NULL; p = p->next)
+		printf("%s ", p->name);
+	printf("\n");
+	pcap_freealldevs(all);
+}
+
+/* args: tap file count direction */
+static void
+capture(int argc __unused, char *argv[])
+{
+	pcap_t *p;
+	pcap_dumper_t *d;
+	pcap_direction_t dir;
+	int cnt;
+
+	cnt = strtolerr(argv[2]);
+	dir = strtodir(argv[3]);
+	p = pcap_open(argv[0], dir);
+
+	if ((d = pcap_dump_open(p, argv[1])) == NULL)
+		errx(1, "pcap_dump_open: %s", pcap_geterr(p));
+
+	if (pcap_loop(p, cnt, pcap_dump, (u_char *)d) != 0)
+		errx(1, "pcap_loop: %s", pcap_geterr(p));
+	pcap_dump_close(d);
+}
+
+static void
+inject_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *bytes)
+{
+	pcap_t *p = (pcap_t *)user;
+
+	if (h->caplen != h->len)
+		errx(1, "incomplete packet %u of %u", h->caplen, h->len);
+
+	if (pcap_inject(p, bytes, h->caplen) != (int)h->caplen)
+		errx(1, "pcap_inject: %s", errbuf);
+}
+
+/* args: tap file count */
+static void
+inject(int argc __unused, char *argv[])
+{
+	pcap_t *p, *d;
+	int cnt;
+
+	cnt = strtolerr(argv[2]);
+	p = pcap_open(argv[0], PCAP_D_INOUT);
+
+	if ((d = pcap_open_offline(argv[1], errbuf)) == NULL)
+		errx(1, "pcap_open_offline: %s", errbuf);
+	if (pcap_loop(d, cnt, inject_packet, (u_char *)p) != 0)
+		errx(1, "pcap_loop: %s", pcap_geterr(p));
+	pcap_close(p);
+	pcap_close(d);
+}
+
+struct packet {
+	STAILQ_ENTRY(packet)	next;
+	const void		*data;
+	u_int			caplen;
+	u_int			len;
+};
+STAILQ_HEAD(plist, packet);
+
+static void
+store_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *bytes)
+{
+	struct plist *list = (struct plist *)user;
+	struct packet *p;
+
+	p = malloc(sizeof(*p));
+	p->data = bytes;
+	p->caplen = h->caplen;
+	p->len = h->len;
+	STAILQ_INSERT_TAIL(list, p, next);
+}
+
+/* args: file1 file2 */
+static void
+compare(int argc __unused, char *argv[])
+{
+	pcap_t *f1, *f2;
+	struct plist
+	    list1 = STAILQ_HEAD_INITIALIZER(list1),
+	    list2 = STAILQ_HEAD_INITIALIZER(list2);
+	struct packet *p1, *p2;
+	u_int cnt;
+
+        if ((f1 = pcap_open_offline(argv[0], errbuf)) == NULL)
+                errx(1, "pcap_open_offline: %s", errbuf);
+	if (pcap_loop(f1, 0, store_packet, (u_char *)&list1) != 0)
+		errx(1, "pcap_loop: %s", pcap_geterr(f1));
+        if ((f2 = pcap_open_offline(argv[1], errbuf)) == NULL)
+                errx(1, "pcap_open_offline: %s", errbuf);
+	if (pcap_loop(f2, 0, store_packet, (u_char *)&list2) != 0)
+		errx(1, "pcap_loop: %s", pcap_geterr(f2));
+
+	for (p1 = STAILQ_FIRST(&list1), p2 = STAILQ_FIRST(&list2), cnt = 1;
+	    p1 != NULL && p2 != NULL;
+	    p1 = STAILQ_NEXT(p1, next), p2 = STAILQ_NEXT(p2, next), cnt++) {
+		if (p1->len != p2->len)
+			errx(1, "packet #%u length %u != %u",
+			    cnt, p1->len, p2->len);
+		if (p1->caplen != p2->caplen)
+			errx(1, "packet #%u capture length %u != %u",
+			    cnt, p1->caplen, p2->caplen);
+		if (memcmp(p1->data, p2->data, p1->caplen) != 0)
+			errx(1, "packet #%u payload different", cnt);
+	}
+	if (p1 != NULL || p2 != NULL)
+		errx(1, "packet count different");
+
+	pcap_close(f1);
+	pcap_close(f2);
+}
+
+static const struct cmd {
+	const char *cmd;
+	void (*func)(int, char **);
+	u_int argc;
+} cmds[] = {
+	{ .cmd = "list",	.func = list,	.argc = 0 },
+	{ .cmd = "inject",	.func = inject,	.argc = 3 },
+	{ .cmd = "capture",	.func = capture,.argc = 4 },
+	{ .cmd = "compare",	.func = compare,.argc = 2 },
+};
+
+int
+main(int argc, char *argv[])
+{
+
+	if (argc < 2) {
+		fprintf(stderr, "Usage: %s ", argv[0]);
+		for (u_int i = 0; i < nitems(cmds); i++)
+			fprintf(stderr, "%s%s", cmds[i].cmd,
+			    i != nitems(cmds) - 1 ? "|" : "\n");
+		exit(1);
+	}
+
+	for (u_int i = 0; i < nitems(cmds); i++)
+		if (strcasecmp(argv[1], cmds[i].cmd) == 0) {
+			argc -= 2;
+			argv += 2;
+			if (argc < (int)cmds[i].argc)
+				errx(1, "%s takes %u args",
+				    cmds[i].cmd, cmds[i].argc);
+			cmds[i].func(argc, argv);
+			return (0);
+		}
+
+	warnx("Unknown command %s\n", argv[1]);
+	return (1);
+}