debian conntrack 0.9.14-2

1 files changed, 312 insertions, 0 deletions

diff --git a/src/channel.c b/src/channel.c
new file mode 100644
index 0000000..818bb01
--- /dev/null
+++ b/src/channel.c
@@ -0,0 +1,312 @@
+/*
+ * (C) 2009 by Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <net/if.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <netinet/in.h>
+#include <errno.h>
+
+#include "conntrackd.h"
+#include "channel.h"
+#include "network.h"
+#include "queue.h"
+
+static struct channel_ops *ops[CHANNEL_MAX];
+extern struct channel_ops channel_mcast;
+extern struct channel_ops channel_udp;
+extern struct channel_ops channel_tcp;
+
+static struct queue *errorq;
+
+int channel_init(void)
+{
+	ops[CHANNEL_MCAST] = &channel_mcast;
+	ops[CHANNEL_UDP] = &channel_udp;
+	ops[CHANNEL_TCP] = &channel_tcp;
+
+	errorq = queue_create("errorq", CONFIG(channelc).error_queue_length, 0);
+	if (errorq == NULL) {
+		return -1;
+	}
+	return 0;
+}
+
+void channel_end(void)
+{
+	queue_destroy(errorq);
+}
+
+struct channel_buffer {
+	char	*data;
+	int	size;
+	int	len;
+};
+
+static struct channel_buffer *
+channel_buffer_open(int mtu, int headersiz)
+{
+	struct channel_buffer *b;
+
+	b = calloc(sizeof(struct channel_buffer), 1);
+	if (b == NULL)
+		return NULL;
+
+	b->size = mtu - headersiz;
+
+	b->data = malloc(b->size);
+	if (b->data == NULL) {
+		free(b);
+		return NULL;
+	}
+	return b;
+}
+
+static void
+channel_buffer_close(struct channel_buffer *b)
+{
+	if (b == NULL)
+		return;
+
+	free(b->data);
+	free(b);
+}
+
+struct channel *
+channel_open(struct channel_conf *cfg)
+{
+	struct channel *c;
+	struct ifreq ifr;
+	int fd;
+
+	if (cfg->channel_type >= CHANNEL_MAX)
+		return NULL;
+	if (!cfg->channel_ifname[0])
+		return NULL;
+	if (cfg->channel_flags >= CHANNEL_F_MAX)
+		return NULL;
+
+	c = calloc(sizeof(struct channel), 1);
+	if (c == NULL)
+		return NULL;
+
+	c->channel_type = cfg->channel_type;
+
+	fd = socket(AF_INET, SOCK_DGRAM, 0);
+	if (fd == -1) {
+		free(c);
+		return NULL;
+	}
+	strncpy(ifr.ifr_name, cfg->channel_ifname, sizeof(ifr.ifr_name));
+
+	if (ioctl(fd, SIOCGIFMTU, &ifr) == -1) {
+		free(c);
+		return NULL;
+	}
+	close(fd);
+	c->channel_ifmtu = ifr.ifr_mtu;
+
+	c->channel_ifindex = if_nametoindex(cfg->channel_ifname);
+	if (c->channel_ifindex == 0) {
+		free(c);
+		return NULL;
+	}
+	c->ops = ops[cfg->channel_type];
+
+	if (cfg->channel_flags & CHANNEL_F_BUFFERED) {
+		c->buffer = channel_buffer_open(c->channel_ifmtu,
+						c->ops->headersiz);
+		if (c->buffer == NULL) {
+			free(c);
+			return NULL;
+		}
+	}
+	c->channel_flags = cfg->channel_flags;
+
+	c->data = c->ops->open(&cfg->u);
+	if (c->data == NULL) {
+		channel_buffer_close(c->buffer);
+		free(c);
+		return NULL;
+	}
+	return c;
+}
+
+void
+channel_close(struct channel *c)
+{
+	c->ops->close(c->data);
+	if (c->channel_flags & CHANNEL_F_BUFFERED)
+		channel_buffer_close(c->buffer);
+	free(c);
+}
+
+struct channel_error {
+	char			*data;
+	int			len;
+};
+
+static void channel_enqueue_errors(struct channel *c)
+{
+	struct queue_object *qobj;
+	struct channel_error *error;
+
+	qobj = queue_object_new(Q_ELEM_ERR, sizeof(struct channel_error));
+	if (qobj == NULL)
+		return;
+
+	error		= (struct channel_error *)qobj->data;
+	error->len	= c->buffer->len;
+
+	error->data = malloc(c->buffer->len);
+	if (error->data == NULL) {
+		queue_object_free(qobj);
+		return;
+	}
+	memcpy(error->data, c->buffer->data, c->buffer->len);
+	if (queue_add(errorq, &qobj->qnode) < 0) {
+		if (errno == ENOSPC) {
+			struct queue_node *tail;
+			struct channel_error *tmp;
+
+			tail = queue_del_head(errorq);
+			tmp = queue_node_data(tail);
+			free(tmp->data);
+			queue_object_free((struct queue_object *)tail);
+
+			queue_add(errorq, &qobj->qnode);
+		}
+	}
+}
+
+static int channel_handle_error_step(struct queue_node *n, const void *data2)
+{
+	struct channel_error *error;
+	const struct channel *c = data2;
+	int ret;
+
+	error = queue_node_data(n);
+	ret = c->ops->send(c->data, error->data, error->len);
+	if (ret != -1) {
+		/* Success. Delete it from the error queue. */
+		queue_del(n);
+		free(error->data);
+		queue_object_free((struct queue_object *)n);
+	} else {
+		/* We failed to deliver, give up now, try later. */
+		return 1;
+	}
+	return 0;
+}
+
+static int channel_handle_errors(struct channel *c)
+{
+	/* there are pending errors that we have to handle. */
+	if (c->channel_flags & CHANNEL_F_ERRORS && queue_len(errorq) > 0) {
+		queue_iterate(errorq, c, channel_handle_error_step);
+		return queue_len(errorq) > 0;
+	}
+	return 0;
+}
+
+int channel_send(struct channel *c, const struct nethdr *net)
+{
+	int ret = 0, len = ntohs(net->len), pending_errors;
+
+	pending_errors = channel_handle_errors(c);
+
+	if (!(c->channel_flags & CHANNEL_F_BUFFERED)) {
+		c->ops->send(c->data, net, len);
+		return 1;
+	}
+retry:
+	if (c->buffer->len + len < c->buffer->size) {
+		memcpy(c->buffer->data + c->buffer->len, net, len);
+		c->buffer->len += len;
+	} else {
+		/* We've got pending packets to deliver, enqueue this
+		 * packet to avoid possible re-ordering. */
+		if (pending_errors) {
+			channel_enqueue_errors(c);
+		} else {
+			ret = c->ops->send(c->data, c->buffer->data,
+					   c->buffer->len);
+			if (ret == -1 &&
+			    (c->channel_flags & CHANNEL_F_ERRORS)) {
+				/* Give it another chance to deliver. */
+				channel_enqueue_errors(c);
+			}
+		}
+		ret = 1;
+		c->buffer->len = 0;
+		goto retry;
+	}
+	return ret;
+}
+
+int channel_send_flush(struct channel *c)
+{
+	int ret, pending_errors;
+
+	pending_errors = channel_handle_errors(c);
+
+	if (!(c->channel_flags & CHANNEL_F_BUFFERED) || c->buffer->len == 0)
+		return 0;
+
+	/* We still have pending errors to deliver, avoid any re-ordering. */
+	if (pending_errors) {
+		channel_enqueue_errors(c);
+	} else {
+		ret = c->ops->send(c->data, c->buffer->data, c->buffer->len);
+		if (ret == -1 && (c->channel_flags & CHANNEL_F_ERRORS)) {
+			/* Give it another chance to deliver it. */
+			channel_enqueue_errors(c);
+		}
+	}
+	c->buffer->len = 0;
+	return 1;
+}
+
+int channel_recv(struct channel *c, char *buf, int size)
+{
+	return c->ops->recv(c->data, buf, size);
+}
+
+int channel_get_fd(struct channel *c)
+{
+	return c->ops->get_fd(c->data);
+}
+
+void channel_stats(struct channel *c, int fd)
+{
+	return c->ops->stats(c, fd);
+}
+
+void channel_stats_extended(struct channel *c, int active,
+			    struct nlif_handle *h, int fd)
+{
+	return c->ops->stats_extended(c, active, h, fd);
+}
+
+int channel_accept_isset(struct channel *c, fd_set *readfds)
+{
+	return c->ops->accept_isset(c, readfds);
+}
+
+int channel_isset(struct channel *c, fd_set *readfds)
+{
+	return c->ops->isset(c, readfds);
+}
+
+int channel_accept(struct channel *c)
+{
+	return c->ops->accept(c);
+}