sync dhcrelay's packet processing with dhcpd's.

[Stuart Henderson]

Not sure if I sent this before, but I found it sitting in a tree.
dhcrelay missed out on some of the changes made to dhcpd/dhclient's
packet.c. OK to sync them up? After this set of patches, the only
difference from dhcpd's is the intentional ipsec-related one.

OK?


"Remove unused (a.k.a. always passed NULL) parameter 'data' from
decode_udp_ip_header() and the useless check of it. Part of original
diff from pelikan about udp length errors."

dhcpd/bpf.c:1.8->1.9
dhcpd/dhcpd.h:1.45->1.46
dhcpd/packet.c:1.4->1.5

diff --git bpf.c bpf.c
index fad2e0a..298d3ec 100644
--- bpf.c
+++ bpf.c
@@ -377,7 +377,7 @@ receive_packet(struct interface_info *interface, unsigned char *buf,

/* Decode the IP and UDP headers... */
offset = decode_udp_ip_header(interface, interface->rbuf,
- interface->rbuf_offset, from, NULL, hdr.bh_caplen);
+ interface->rbuf_offset, from, hdr.bh_caplen);

/* If the IP or UDP checksum was bad, skip the packet... */
if (offset < 0) {
diff --git dhcpd.h dhcpd.h
index c1d6917..b80e984 100644
--- dhcpd.h
+++ dhcpd.h
@@ -162,7 +162,7 @@ void remove_protocol(struct protocol *);
void assemble_hw_header(struct interface_info *, unsigned char *,
int *, struct hardware *);
void assemble_udp_ip_header(struct interface_info *, unsigned char *,
- int *, u_int32_t, u_int32_t, unsigned int, unsigned char *, int);
+ int *, u_int32_t, u_int32_t, unsigned int, int);
ssize_t decode_hw_header(struct interface_info *, unsigned char *,
int, struct hardware *);
ssize_t decode_udp_ip_header(struct interface_info *, unsigned char *,
diff --git packet.c packet.c
index 6352f0c..c0e7432 100644
--- packet.c
+++ packet.c
@@ -178,10 +178,11 @@ decode_hw_header(struct interface_info *interface, unsigned char *buf,

ssize_t
decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,
- int bufix, struct sockaddr_in *from, unsigned char *data, int buflen)
+ int bufix, struct sockaddr_in *from, int buflen)
{
struct ip *ip;
struct udphdr *udp;
+ unsigned char *data;
u_int32_t ip_len = (buf[bufix] & 0xf) << 2;
u_int32_t sum, usum;
static int ip_packets_seen;
@@ -190,7 +191,7 @@ decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,
static int udp_packets_bad_checksum;
static int udp_packets_length_checked;
static int udp_packets_length_overflow;
- int len = 0;
+ int len;

ip = (struct ip *)(buf + bufix);
udp = (struct udphdr *)(buf + bufix + ip_len);
@@ -216,30 +217,28 @@ decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,

/*
* Compute UDP checksums, including the ``pseudo-header'', the
- * UDP header and the data. If the UDP checksum field is zero,
+ * UDP header and the data. If the UDP checksum field is zero,
* we're not supposed to do a checksum.
*/
- if (!data) {
- data = buf + bufix + ip_len + sizeof(*udp);
- len = ntohs(udp->uh_ulen) - sizeof(*udp);
- udp_packets_length_checked++;
- if ((len < 0) || (len + data > buf + bufix + buflen)) {
- udp_packets_length_overflow++;
- if (udp_packets_length_checked > 4 &&
- udp_packets_length_overflow != 0 &&
- (udp_packets_length_checked /
- udp_packets_length_overflow) < 2) {
- note("%d udp packets in %d too long - dropped",
- udp_packets_length_overflow,
- udp_packets_length_checked);
- udp_packets_length_overflow =
- udp_packets_length_checked = 0;
- }
- return (-1);
+ data = buf + bufix + ip_len + sizeof(*udp);
+ len = ntohs(udp->uh_ulen) - sizeof(*udp);
+ udp_packets_length_checked++;
+ if ((len < 0) || (len + data > buf + bufix + buflen)) {
+ udp_packets_length_overflow++;
+ if (udp_packets_length_checked > 4 &&
+ udp_packets_length_overflow != 0 &&
+ (udp_packets_length_checked /
+ udp_packets_length_overflow) < 2) {
+ note("%d udp packets in %d too long - dropped",
+ udp_packets_length_overflow,
+ udp_packets_length_checked);
+ udp_packets_length_overflow =
+ udp_packets_length_checked = 0;
}
- if (len + data != buf + bufix + buflen)
- debug("accepting packet with data after udp payload.");
+ return (-1);
}
+ if (len + data != buf + bufix + buflen)
+ debug("accepting packet with data after udp payload.");

usum = udp->uh_sum;
udp->uh_sum = 0;



"Nuke local #define ETHER_HEADER_SIZE and use the identical value'd
ETHER_HDR_LEN from if_ether.h. dhclient change ok matthew@ as part
of larger diff."

dhcpd/packet.c:1.5->1.6

diff --git packet.c packet.c
index c0e7432..cbb7c8d 100644
--- packet.c
+++ packet.c
@@ -47,8 +47,6 @@
#include <netinet/udp.h>
#include <netinet/if_ether.h>

-#define ETHER_HEADER_SIZE (ETHER_ADDR_LEN * 2 + sizeof(u_int16_t))
-
u_int32_t checksum(unsigned char *, unsigned, u_int32_t);
u_int32_t wrapsum(u_int32_t);

@@ -101,8 +99,8 @@ assemble_hw_header(struct interface_info *interface, unsigned char *buf,

eh.ether_type = htons(ETHERTYPE_IP);

- memcpy(&buf[*bufix], &eh, ETHER_HEADER_SIZE);
- *bufix += ETHER_HEADER_SIZE;
+ memcpy(&buf[*bufix], &eh, ETHER_HDR_LEN);
+ *bufix += ETHER_HDR_LEN;
}

void
@@ -165,7 +163,7 @@ decode_hw_header(struct interface_info *interface, unsigned char *buf,
bzero(&eh, sizeof(eh));
offset = ENC_HDRLEN + ip_len;
} else {
- memcpy(&eh, buf + bufix, ETHER_HEADER_SIZE);
+ memcpy(&eh, buf + bufix, ETHER_HDR_LEN);
offset = sizeof(eh);
}




"Variables to count seen packets should be unsigned."

dhcpd/packet.c:1.7->1.8

diff --git packet.c packet.c
index cbb7c8d..a71d79f 100644
--- packet.c
+++ packet.c
@@ -183,12 +183,12 @@ decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,
unsigned char *data;
u_int32_t ip_len = (buf[bufix] & 0xf) << 2;
u_int32_t sum, usum;
- static int ip_packets_seen;
- static int ip_packets_bad_checksum;
- static int udp_packets_seen;
- static int udp_packets_bad_checksum;
- static int udp_packets_length_checked;
- static int udp_packets_length_overflow;
+ static unsigned int ip_packets_seen;
+ static unsigned int ip_packets_bad_checksum;
+ static unsigned int udp_packets_seen;
+ static unsigned int udp_packets_bad_checksum;
+ static unsigned int udp_packets_length_checked;
+ static unsigned int udp_packets_length_overflow;
int len;

ip = (struct ip *)(buf + bufix);
@@ -200,7 +200,7 @@ decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,
ip_packets_bad_checksum++;
if (ip_packets_seen > 4 && ip_packets_bad_checksum != 0 &&
(ip_packets_seen / ip_packets_bad_checksum) < 2) {
- note("%d bad IP checksums seen in %d packets",
+ note("%u bad IP checksums seen in %u packets",
ip_packets_bad_checksum, ip_packets_seen);
ip_packets_seen = ip_packets_bad_checksum = 0;
}
@@ -227,7 +227,7 @@ decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,
udp_packets_length_overflow != 0 &&
(udp_packets_length_checked /
udp_packets_length_overflow) < 2) {
- note("%d udp packets in %d too long - dropped",
+ note("%u udp packets in %u too long - dropped",
udp_packets_length_overflow,
udp_packets_length_checked);
udp_packets_length_overflow =
@@ -251,7 +251,7 @@ decode_udp_ip_header(struct interface_info *interface, unsigned char *buf,
udp_packets_bad_checksum++;
if (udp_packets_seen > 4 && udp_packets_bad_checksum != 0 &&
(udp_packets_seen / udp_packets_bad_checksum) < 2) {
- note("%d bad udp checksums in %d packets",
+ note("%u bad udp checksums in %u packets",
udp_packets_bad_checksum, udp_packets_seen);
udp_packets_seen = udp_packets_bad_checksum = 0;
}