1 files changed, 351 insertions, 0 deletions
diff --git a/lib/libpcap/libpcap/pcap-dbus.c b/lib/libpcap/libpcap/pcap-dbus.c
new file mode 100644
index 0000000..1252975
--- /dev/null
+++ b/lib/libpcap/libpcap/pcap-dbus.c
@@ -0,0 +1,351 @@
+/*
+ * Copyright (c) 2012 Jakub Zawadzki
+ * 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.
+ * 3. The name of the author may not be used to endorse or promote
+ * products derived from this software without specific prior written
+ * permission.
+ *
+ * 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
+ * OWNER 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <string.h>
+
+#include <time.h>
+#include <sys/time.h>
+
+#include <dbus/dbus.h>
+
+#include "pcap-int.h"
+#include "pcap-dbus.h"
+
+/*
+ * Private data for capturing on D-Bus.
+ */
+struct pcap_dbus {
+	DBusConnection *conn;
+	u_int	packets_read;	/* count of packets read */
+};
+
+static int
+dbus_read(pcap_t *handle, int max_packets _U_, pcap_handler callback, u_char *user)
+{
+	struct pcap_dbus *handlep = handle->priv;
+
+	struct pcap_pkthdr pkth;
+	DBusMessage *message;
+
+	char *raw_msg;
+	int raw_msg_len;
+
+	int count = 0;
+
+	message = dbus_connection_pop_message(handlep->conn);
+
+	while (!message) {
+		/* XXX handle->opt.timeout = timeout_ms; */
+		if (!dbus_connection_read_write(handlep->conn, 100)) {
+			pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Connection closed");
+			return -1;
+		}
+
+		if (handle->break_loop) {
+			handle->break_loop = 0;
+			return -2;
+		}
+
+		message = dbus_connection_pop_message(handlep->conn);
+	}
+
+	if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL, "Disconnected")) {
+		pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Disconnected");
+		return -1;
+	}
+
+	if (dbus_message_marshal(message, &raw_msg, &raw_msg_len)) {
+		pkth.caplen = pkth.len = raw_msg_len;
+		/* pkth.caplen = min (payload_len, handle->snapshot); */
+
+		gettimeofday(&pkth.ts, NULL);
+		if (handle->fcode.bf_insns == NULL ||
+		    bpf_filter(handle->fcode.bf_insns, (u_char *)raw_msg, pkth.len, pkth.caplen)) {
+			handlep->packets_read++;
+			callback(user, &pkth, (u_char *)raw_msg);
+			count++;
+		}
+
+		dbus_free(raw_msg);
+	}
+	return count;
+}
+
+static int
+dbus_write(pcap_t *handle, const void *buf, size_t size)
+{
+	/* XXX, not tested */
+	struct pcap_dbus *handlep = handle->priv;
+
+	DBusError error = DBUS_ERROR_INIT;
+	DBusMessage *msg;
+
+	if (!(msg = dbus_message_demarshal(buf, size, &error))) {
+		pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "dbus_message_demarshal() failed: %s", error.message);
+		dbus_error_free(&error);
+		return -1;
+	}
+
+	dbus_connection_send(handlep->conn, msg, NULL);
+	dbus_connection_flush(handlep->conn);
+
+	dbus_message_unref(msg);
+	return 0;
+}
+
+static int
+dbus_stats(pcap_t *handle, struct pcap_stat *stats)
+{
+	struct pcap_dbus *handlep = handle->priv;
+
+	stats->ps_recv = handlep->packets_read;
+	stats->ps_drop = 0;
+	stats->ps_ifdrop = 0;
+	return 0;
+}
+
+static void
+dbus_cleanup(pcap_t *handle)
+{
+	struct pcap_dbus *handlep = handle->priv;
+
+	dbus_connection_unref(handlep->conn);
+
+	pcap_cleanup_live_common(handle);
+}
+
+/*
+ * We don't support non-blocking mode.  I'm not sure what we'd
+ * do to support it and, given that we don't support select()/
+ * poll()/epoll_wait()/kevent() etc., it probably doesn't
+ * matter.
+ */
+static int
+dbus_getnonblock(pcap_t *p)
+{
+	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
+	    "Non-blocking mode isn't supported for capturing on D-Bus");
+	return (-1);
+}
+
+static int
+dbus_setnonblock(pcap_t *p, int nonblock _U_)
+{
+	pcap_snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
+	    "Non-blocking mode isn't supported for capturing on D-Bus");
+	return (-1);
+}
+
+static int
+dbus_activate(pcap_t *handle)
+{
+#define EAVESDROPPING_RULE "eavesdrop=true,"
+
+	static const char *rules[] = {
+		EAVESDROPPING_RULE "type='signal'",
+		EAVESDROPPING_RULE "type='method_call'",
+		EAVESDROPPING_RULE "type='method_return'",
+		EAVESDROPPING_RULE "type='error'",
+	};
+
+	#define N_RULES sizeof(rules)/sizeof(rules[0])
+
+	struct pcap_dbus *handlep = handle->priv;
+	const char *dev = handle->opt.device;
+
+	DBusError error = DBUS_ERROR_INIT;
+	u_int i;
+
+	if (strcmp(dev, "dbus-system") == 0) {
+		if (!(handlep->conn = dbus_bus_get(DBUS_BUS_SYSTEM, &error))) {
+			pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Failed to get system bus: %s", error.message);
+			dbus_error_free(&error);
+			return PCAP_ERROR;
+		}
+
+	} else if (strcmp(dev, "dbus-session") == 0) {
+		if (!(handlep->conn = dbus_bus_get(DBUS_BUS_SESSION, &error))) {
+			pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Failed to get session bus: %s", error.message);
+			dbus_error_free(&error);
+			return PCAP_ERROR;
+		}
+
+	} else if (strncmp(dev, "dbus://", 7) == 0) {
+		const char *addr = dev + 7;
+
+		if (!(handlep->conn = dbus_connection_open(addr, &error))) {
+			pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Failed to open connection to: %s: %s", addr, error.message);
+			dbus_error_free(&error);
+			return PCAP_ERROR;
+		}
+
+		if (!dbus_bus_register(handlep->conn, &error)) {
+			pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Failed to register bus %s: %s\n", addr, error.message);
+			dbus_error_free(&error);
+			return PCAP_ERROR;
+		}
+
+	} else {
+		pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Can't get bus address from %s", handle->opt.device);
+		return PCAP_ERROR;
+	}
+
+	/* Initialize some components of the pcap structure. */
+	handle->bufsize = 0;
+	handle->offset = 0;
+	handle->linktype = DLT_DBUS;
+	handle->read_op = dbus_read;
+	handle->inject_op = dbus_write;
+	handle->setfilter_op = install_bpf_program; /* XXX, later add support for dbus_bus_add_match() */
+	handle->setdirection_op = NULL;
+	handle->set_datalink_op = NULL;      /* can't change data link type */
+	handle->getnonblock_op = dbus_getnonblock;
+	handle->setnonblock_op = dbus_setnonblock;
+	handle->stats_op = dbus_stats;
+	handle->cleanup_op = dbus_cleanup;
+
+#ifndef _WIN32
+	/*
+	 * Unfortunately, trying to do a select()/poll()/epoll_wait()/
+	 * kevent()/etc. on a D-Bus connection isn't a simple
+	 * case of "give me an FD on which to wait".
+	 *
+	 * Apparently, you have to register "add watch", "remove watch",
+	 * and "toggle watch" functions with
+	 * dbus_connection_set_watch_functions(),
+	 * keep a *set* of FDs, add to that set in the "add watch"
+	 * function, subtract from it in the "remove watch" function,
+	 * and either add to or subtract from that set in the "toggle
+	 * watch" function, and do the wait on *all* of the FDs in the
+	 * set.  (Yes, you need the "toggle watch" function, so that
+	 * the main loop doesn't itself need to check for whether
+	 * a given watch is enabled or disabled - most libpcap programs
+	 * know nothing about D-Bus and shouldn't *have* to know anything
+	 * about D-Bus other than how to decode D-Bus messages.)
+	 *
+	 * Implementing that would require considerable changes in
+	 * the way libpcap exports "selectable FDs" to its client.
+	 * Until that's done, we just say "you can't do that".
+	 */
+	handle->selectable_fd = handle->fd = -1;
+#endif
+
+	if (handle->opt.rfmon) {
+		/*
+		 * Monitor mode doesn't apply to dbus connections.
+		 */
+		dbus_cleanup(handle);
+		return PCAP_ERROR_RFMON_NOTSUP;
+	}
+
+	/*
+	 * Turn a negative snapshot value (invalid), a snapshot value of
+	 * 0 (unspecified), or a value bigger than the normal maximum
+	 * value, into the maximum message length for D-Bus (128MB).
+	 */
+	if (handle->snapshot <= 0 || handle->snapshot > 134217728)
+		handle->snapshot = 134217728;
+
+	/* dbus_connection_set_max_message_size(handlep->conn, handle->snapshot); */
+	if (handle->opt.buffer_size != 0)
+		dbus_connection_set_max_received_size(handlep->conn, handle->opt.buffer_size);
+
+	for (i = 0; i < N_RULES; i++) {
+		dbus_bus_add_match(handlep->conn, rules[i], &error);
+		if (dbus_error_is_set(&error)) {
+			dbus_error_free(&error);
+
+			/* try without eavesdrop */
+			dbus_bus_add_match(handlep->conn, rules[i] + strlen(EAVESDROPPING_RULE), &error);
+			if (dbus_error_is_set(&error)) {
+				pcap_snprintf(handle->errbuf, PCAP_ERRBUF_SIZE, "Failed to add bus match: %s\n", error.message);
+				dbus_error_free(&error);
+				dbus_cleanup(handle);
+				return PCAP_ERROR;
+			}
+		}
+	}
+
+	return 0;
+}
+
+pcap_t *
+dbus_create(const char *device, char *ebuf, int *is_ours)
+{
+	pcap_t *p;
+
+	if (strcmp(device, "dbus-system") &&
+		strcmp(device, "dbus-session") &&
+		strncmp(device, "dbus://", 7))
+	{
+		*is_ours = 0;
+		return NULL;
+	}
+
+	*is_ours = 1;
+	p = pcap_create_common(ebuf, sizeof (struct pcap_dbus));
+	if (p == NULL)
+		return (NULL);
+
+	p->activate_op = dbus_activate;
+	/*
+	 * Set these up front, so that, even if our client tries
+	 * to set non-blocking mode before we're activated, or
+	 * query the state of non-blocking mode, they get an error,
+	 * rather than having the non-blocking mode option set
+	 * for use later.
+	 */
+	p->getnonblock_op = dbus_getnonblock;
+	p->setnonblock_op = dbus_setnonblock;
+	return (p);
+}
+
+int
+dbus_findalldevs(pcap_if_list_t *devlistp, char *err_str)
+{
+	/*
+	 * The notion of "connected" vs. "disconnected" doesn't apply.
+	 * XXX - what about the notions of "up" and "running"?
+	 */
+	if (add_dev(devlistp, "dbus-system",
+	    PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE, "D-Bus system bus",
+	    err_str) == NULL)
+		return -1;
+	if (add_dev(devlistp, "dbus-session",
+	    PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE, "D-Bus session bus",
+	    err_str) == NULL)
+		return -1;
+	return 0;
+}
+