Split DHCP code off into a separate source code file

diff --git a/Makefile b/Makefile
index 1715881a1bed7484fa86e6be46a0b0c139543e80..5fd54e8f823af41528b2f9a6237c7e75e61f63a0 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -4,7 +4,7 @@ LDFLAGS =
 
 all: relayd 
 
-relayd: uloop.o main.o route.o
+relayd: uloop.o main.o route.o dhcp.o
        $(CC) -o $@ $^ $(LDFLAGS)
 
 relayd.h: list.h

diff --git a/dhcp.c b/dhcp.c
new file mode 100644 (file)
index 0000000..a144346
--- /dev/null
+++ b/dhcp.c
@@ -0,0 +1,122 @@
+/*
+ *   Copyright (C) 2010 Felix Fietkau <nbd@openwrt.org>
+ *
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License v2 as published by
+ *   the Free Software Foundation.
+ *
+ *   This 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 this program; if not, write to the Free Software
+ *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <sys/socket.h>
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#include "relayd.h"
+
+struct ip_packet {
+       struct ether_header eth;
+       struct iphdr iph;
+} __packed;
+
+struct dhcp_header {
+       uint8_t op, htype, hlen, hops;
+       uint32_t xit;
+       uint16_t secs, flags;
+       struct in_addr ciaddr, yiaddr, siaddr, giaddr;
+       unsigned char chaddr[16];
+       unsigned char sname[64];
+       unsigned char file[128];
+} __packed;
+
+static uint16_t
+chksum(uint16_t sum, const uint8_t *data, uint16_t len)
+{
+       const uint8_t *last;
+       uint16_t t;
+
+       last = data + len - 1;
+
+       while(data < last) {
+               t = (data[0] << 8) + data[1];
+               sum += t;
+               if(sum < t)
+                       sum++;
+               data += 2;
+       }
+
+       if(data == last) {
+               t = (data[0] << 8) + 0;
+               sum += t;
+               if(sum < t)
+                       sum++;
+       }
+
+       return sum;
+}
+
+bool relayd_handle_dhcp_packet(struct relayd_interface *rif, void *data, int len, bool forward)
+{
+       struct ip_packet *pkt = data;
+       struct udphdr *udp;
+       struct dhcp_header *dhcp;
+       int udplen;
+       uint16_t sum;
+
+       if (pkt->eth.ether_type != htons(ETH_P_IP))
+               return false;
+
+       if (pkt->iph.version != 4)
+               return false;
+
+       if (pkt->iph.protocol != IPPROTO_UDP)
+               return false;
+
+       udp = (void *) ((char *) &pkt->iph + (pkt->iph.ihl << 2));
+       dhcp = (void *) (udp + 1);
+
+       udplen = ntohs(udp->len);
+       if (udplen > len - ((char *) udp - (char *) data))
+               return false;
+
+       if (udp->dest != htons(67) && udp->source != htons(67))
+               return false;
+
+       if (dhcp->op != 1 && dhcp->op != 2)
+               return false;
+
+       if (!forward)
+               return true;
+
+       if (dhcp->op == 2)
+               relayd_refresh_host(rif, pkt->eth.ether_shost, (void *) &pkt->iph.saddr);
+
+       DPRINTF(2, "%s: handling DHCP %s\n", rif->ifname, (dhcp->op == 1 ? "request" : "response"));
+
+       dhcp->flags |= htons(DHCP_FLAG_BROADCAST);
+
+       udp->check = 0;
+       sum = udplen + IPPROTO_UDP;
+       sum = chksum(sum, (void *) &pkt->iph.saddr, 8);
+       sum = chksum(sum, (void *) udp, udplen);
+       if (sum == 0)
+               sum = 0xffff;
+
+       udp->check = htons(~sum);
+
+       relayd_forward_bcast_packet(rif, data, len);
+
+       return true;
+}
+
+

diff --git a/main.c b/main.c
index 975e1ff82712f58ab6c4e8bd84d95a5ba5e9c50b..62d7c2b25fd72e3d2fdbd6418755b9a2a337abae 100644 (file)
--- a/main.c
+++ b/main.c
@@ -329,7 +329,7 @@ static void recv_packet(struct uloop_fd *fd, unsigned int events)
        } while (1);
 }
 
-static void forward_bcast_packet(struct relayd_interface *from_rif, void *packet, int len)
+void relayd_forward_bcast_packet(struct relayd_interface *from_rif, void *packet, int len)
 {
        struct relayd_interface *rif;
        struct ether_header *eth = packet;
@@ -344,86 +344,6 @@ static void forward_bcast_packet(struct relayd_interface *from_rif, void *packet
        }
 }
 
-static uint16_t
-chksum(uint16_t sum, const uint8_t *data, uint16_t len)
-{
-       const uint8_t *last;
-       uint16_t t;
-
-       last = data + len - 1;
-
-       while(data < last) {
-               t = (data[0] << 8) + data[1];
-               sum += t;
-               if(sum < t)
-                       sum++;
-               data += 2;
-       }
-
-       if(data == last) {
-               t = (data[0] << 8) + 0;
-               sum += t;
-               if(sum < t)
-                       sum++;
-       }
-
-       return sum;
-}
-
-static bool forward_dhcp_packet(struct relayd_interface *rif, void *data, int len)
-{
-       struct ip_packet *pkt = data;
-       struct udphdr *udp;
-       struct dhcp_header *dhcp;
-       int udplen;
-       uint16_t sum;
-
-       if (pkt->eth.ether_type != htons(ETH_P_IP))
-               return false;
-
-       if (pkt->iph.version != 4)
-               return false;
-
-       if (pkt->iph.protocol != IPPROTO_UDP)
-               return false;
-
-       udp = (void *) ((char *) &pkt->iph + (pkt->iph.ihl << 2));
-       dhcp = (void *) (udp + 1);
-
-       udplen = ntohs(udp->len);
-       if (udplen > len - ((char *) udp - (char *) data))
-               return false;
-
-       if (udp->dest != htons(67) && udp->source != htons(67))
-               return false;
-
-       if (dhcp->op != 1 && dhcp->op != 2)
-               return false;
-
-       if (!forward_dhcp)
-               return true;
-
-       if (dhcp->op == 2)
-               relayd_refresh_host(rif, pkt->eth.ether_shost, (void *) &pkt->iph.saddr);
-
-       DPRINTF(2, "%s: handling DHCP %s\n", rif->ifname, (dhcp->op == 1 ? "request" : "response"));
-
-       dhcp->flags |= htons(DHCP_FLAG_BROADCAST);
-
-       udp->check = 0;
-       sum = udplen + IPPROTO_UDP;
-       sum = chksum(sum, (void *) &pkt->iph.saddr, 8);
-       sum = chksum(sum, (void *) udp, udplen);
-       if (sum == 0)
-               sum = 0xffff;
-
-       udp->check = htons(~sum);
-
-       forward_bcast_packet(rif, data, len);
-
-       return true;
-}
-
 static void recv_bcast_packet(struct uloop_fd *fd, unsigned int events)
 {
        struct relayd_interface *rif = container_of(fd, struct relayd_interface, bcast_fd);
@@ -448,11 +368,11 @@ static void recv_bcast_packet(struct uloop_fd *fd, unsigned int events)
                if (!forward_bcast && !forward_dhcp)
                        continue;
 
-               if (forward_dhcp_packet(rif, pktbuf, pktlen))
+               if (relayd_handle_dhcp_packet(rif, pktbuf, pktlen, forward_dhcp))
                        continue;
 
                if (forward_bcast)
-                       forward_bcast_packet(rif, pktbuf, pktlen);
+                       relayd_forward_bcast_packet(rif, pktbuf, pktlen);
        } while (1);
 }
 

diff --git a/relayd.h b/relayd.h
index c8b023c2a8771dd7a549f878bb7de20bdea62d6d..3ae4edcba15d733c56aba37c939fe778019449c6 100644 (file)
--- a/relayd.h
+++ b/relayd.h
@@ -85,21 +85,6 @@ struct arp_packet {
        struct ether_arp arp;
 } __packed;
 
-struct ip_packet {
-       struct ether_header eth;
-       struct iphdr iph;
-} __packed;
-
-struct dhcp_header {
-       uint8_t op, htype, hlen, hops;
-       uint32_t xit;
-       uint16_t secs, flags;
-       struct in_addr ciaddr, yiaddr, siaddr, giaddr;
-       unsigned char chaddr[16];
-       unsigned char sname[64];
-       unsigned char file[128];
-} __packed;
-
 struct rtnl_req {
        struct nlmsghdr nl;
        struct rtmsg rt;
@@ -127,6 +112,11 @@ void relayd_del_interface_routes(struct relayd_interface *rif);
 int relayd_rtnl_init(void);
 void relayd_rtnl_done(void);
 
-struct relayd_host *relayd_refresh_host(struct relayd_interface *rif, const uint8_t *lladdr, const uint8_t *ipaddr);
+struct relayd_host *relayd_refresh_host(struct relayd_interface *rif,
+                                       const uint8_t *lladdr,
+                                       const uint8_t *ipaddr);
+
+void relayd_forward_bcast_packet(struct relayd_interface *from_rif, void *packet, int len);
+bool relayd_handle_dhcp_packet(struct relayd_interface *rif, void *data, int len, bool forward);
 
 #endif