contrib: fwd - initial C implementation of the uci firewall

1 files changed, 150 insertions, 0 deletions

diff --git a/contrib/fwd/src/fwd_addr.c b/contrib/fwd/src/fwd_addr.c
new file mode 100644
index 0000000000..df5d8e7c2a
--- /dev/null
+++ b/contrib/fwd/src/fwd_addr.c
@@ -0,0 +1,150 @@
+/*
+ * fwd - OpenWrt firewall daemon - rtnetlink communication
+ *
+ *   Copyright (C) 2009 Jo-Philipp Wich <xm@subsignal.org>
+ *
+ * The fwd program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * The fwd program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with the fwd program. If not, see http://www.gnu.org/licenses/.
+ */
+
+
+#include "fwd.h"
+#include "fwd_addr.h"
+
+struct fwd_addr_list * fwd_get_addrs(int fd, int family)
+{
+	struct {
+		  struct nlmsghdr n;
+		  struct ifaddrmsg r;
+	} req;
+
+	int offlen;
+	int rtattrlen;
+	int dump_done;
+	char buf[16384];
+
+	struct rtattr *rta;
+	struct rtattr *rtatp;
+	struct nlmsghdr *nlmp;
+	struct ifaddrmsg *rtmp;
+
+	struct fwd_addr_list *head, *entry;
+
+	/* Build request */
+	memset(&req, 0, sizeof(req));
+	req.n.nlmsg_len   = NLMSG_LENGTH(sizeof(struct ifaddrmsg));
+	req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_ROOT;
+	req.n.nlmsg_type  = RTM_GETADDR;
+	req.r.ifa_family  = family;
+
+	rta = (struct rtattr *)(((char *)&req) + NLMSG_ALIGN(req.n.nlmsg_len));
+	rta->rta_len = RTA_LENGTH(family == AF_INET ? 4 : 16);
+
+	head = entry = NULL;
+
+	/* Send request */
+	if( send(fd, &req, sizeof(req), 0) <= 0 )
+		goto error;
+
+	/* Receive responses */
+	for( dump_done = 0; !dump_done; )
+	{
+		if( (offlen = recv(fd, buf, sizeof(buf), 0)) <= 0 )
+			goto error;
+
+		/* Parse message */
+		for(nlmp = (struct nlmsghdr *)buf; offlen > sizeof(*nlmp);)
+		{
+			/* Dump finished? */
+			if( nlmp->nlmsg_type == NLMSG_DONE )
+			{
+				dump_done = 1;
+				break;
+			}
+
+			int len = nlmp->nlmsg_len;
+			int req_len = len - sizeof(*nlmp);
+
+			if( req_len<0 || len>offlen )
+				goto error;
+
+			if( !NLMSG_OK(nlmp, offlen) )
+				goto error;
+
+			rtmp  = (struct ifaddrmsg *) NLMSG_DATA(nlmp);
+			rtatp = (struct rtattr *) IFA_RTA(rtmp);
+
+			if( !(entry = fwd_alloc_ptr(struct fwd_addr_list)) )
+				goto error;
+
+			entry->index = rtmp->ifa_index;
+			if_indextoname(rtmp->ifa_index, (char *)&entry->ifname);
+
+			rtattrlen = IFA_PAYLOAD(nlmp);
+
+			for( ; RTA_OK(rtatp, rtattrlen); rtatp = RTA_NEXT(rtatp, rtattrlen) )
+			{
+				if( rtatp->rta_type == IFA_ADDRESS )
+				{
+					memcpy(&entry->ipaddr, (char *) RTA_DATA(rtatp), rtatp->rta_len);
+					entry->prefix = rtmp->ifa_prefixlen;
+					entry->family = family;
+				}
+				else if( rtatp->rta_type == IFA_LABEL)
+				{
+					memcpy(&entry->label, (char *) RTA_DATA(rtatp), rtatp->rta_len);
+				}
+			}
+
+			entry->next = head;
+			head = entry;
+
+			offlen -= NLMSG_ALIGN(len);
+			nlmp = (struct nlmsghdr*)((char*)nlmp + NLMSG_ALIGN(len));
+		}
+	}
+
+	return head;
+
+
+	error:
+
+	fwd_free_addrs(head);
+	head = entry = NULL;
+
+	return NULL;
+}
+
+void fwd_free_addrs(struct fwd_addr_list *head)
+{
+	struct fwd_addr_list *entry = head;
+
+	while( entry != NULL )
+	{
+		head = entry->next;
+		free(entry);
+		entry = head;
+	}
+
+	head = entry = NULL;
+}
+
+struct fwd_addr_list * fwd_append_addrs(struct fwd_addr_list *head, struct fwd_addr_list *add)
+{
+	struct fwd_addr_list *entry = head;
+
+	while( entry->next != NULL )
+		entry = entry->next;
+
+	return (entry->next = add);
+}
+