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Makefile: change version to 1.10.0.svn

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udhcpc: make UDP packet sending the same as raw sending in regards
  to error messages. Minor code size shrink. Total size grows due
  to added messages:

   text    data     bss     dec     hex filename
 770312     683    7244  778239   bdfff busybox_old
 770327     683    7244  778254   be00e busybox_unstripped
This commit is contained in:
Denis Vlasenko
2007-12-24 17:32:22 +00:00
parent 299c5c379e
commit 8e5b6f58a2
4 changed files with 57 additions and 47 deletions
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25
networking/udhcp/clientpacket.c
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@ -167,39 +167,40 @@ int send_release(uint32_t server, uint32_t ciaddr)
}
/* return -1 on errors that are fatal for the socket, -2 for those that aren't */
/* Returns -1 on errors that are fatal for the socket, -2 for those that aren't */
int get_raw_packet(struct dhcpMessage *payload, int fd)
{
int bytes;
struct udp_dhcp_packet packet;
uint16_t check;
memset(&packet, 0, sizeof(struct udp_dhcp_packet));
bytes = read(fd, &packet, sizeof(struct udp_dhcp_packet));
memset(&packet, 0, sizeof(packet));
bytes = safe_read(fd, &packet, sizeof(packet));
if (bytes < 0) {
DEBUG("Cannot read on raw listening socket - ignoring");
sleep(1); /* possible down interface, looping condition */
return -1;
return bytes; /* returns -1 */
}
if (bytes < (int) (sizeof(struct iphdr) + sizeof(struct udphdr))) {
DEBUG("Message too short, ignoring");
if (bytes < (int) (sizeof(packet.ip) + sizeof(packet.udp))) {
DEBUG("Packet is too short, ignoring");
return -2;
}
if (bytes < ntohs(packet.ip.tot_len)) {
DEBUG("Truncated packet");
/* packet is bigger than sizeof(packet), we did partial read */
DEBUG("Oversized packet, ignoring");
return -2;
}
/* ignore any extra garbage bytes */
bytes = ntohs(packet.ip.tot_len);
/* Make sure its the right packet for us, and that it passes sanity checks */
/* make sure its the right packet for us, and that it passes sanity checks */
if (packet.ip.protocol != IPPROTO_UDP || packet.ip.version != IPVERSION
|| packet.ip.ihl != (sizeof(packet.ip) >> 2)
|| packet.udp.dest != htons(CLIENT_PORT)
|| bytes > (int) sizeof(struct udp_dhcp_packet)
/* || bytes > (int) sizeof(packet) - can't happen */
|| ntohs(packet.udp.len) != (uint16_t)(bytes - sizeof(packet.ip))
) {
DEBUG("Unrelated/bogus packet");
@ -211,12 +212,12 @@ int get_raw_packet(struct dhcpMessage *payload, int fd)
packet.ip.check = 0;
if (check != udhcp_checksum(&packet.ip, sizeof(packet.ip))) {
DEBUG("Bad IP header checksum, ignoring");
return -1;
return -2;
}
/* verify UDP checksum. IP header has to be modified for this */
memset(&packet.ip, 0, offsetof(struct iphdr, protocol));
/* fields which are not memset: protocol, check, saddr, daddr */
/* ip.xx fields which are not memset: protocol, check, saddr, daddr */
packet.ip.tot_len = packet.udp.len; /* yes, this is needed */
check = packet.udp.check;
packet.udp.check = 0;
@ -228,7 +229,7 @@ int get_raw_packet(struct dhcpMessage *payload, int fd)
memcpy(payload, &packet.data, bytes - (sizeof(packet.ip) + sizeof(packet.udp)));
if (payload->cookie != htonl(DHCP_MAGIC)) {
bb_error_msg("received bogus message (bad magic) - ignoring");
bb_error_msg("received bogus message (bad magic), ignoring");
return -2;
}
DEBUG("Got valid DHCP packet");