package/busybox/patches/241-udhcpc-oversized_packets.patch

   1 Index: busybox-1.4.2/networking/udhcp/packet.c
   2 ===================================================================
   3 --- busybox-1.4.2.orig/networking/udhcp/packet.c        2007-06-04 13:21:32.289067984 +0200
   4 +++ busybox-1.4.2/networking/udhcp/packet.c     2007-06-04 13:21:33.619865672 +0200
   5 @@ -107,6 +107,10 @@
   6         return ~sum;
   7  }
   8
   9 +int udhcp_get_payload_len(struct dhcpMessage *payload)
  10 +{
  11 +       return sizeof(struct dhcpMessage) - MAX_OPTIONS_LEN + end_option(payload->options) + sizeof(payload->options[0]);
  12 +}
  13
  14  /* Construct a ip/udp header for a packet, and specify the source and dest hardware address */
  15  void BUG_sizeof_struct_udp_dhcp_packet_must_be_576(void);
  16 @@ -118,6 +122,7 @@
  17         int result;
  18         struct sockaddr_ll dest;
  19         struct udp_dhcp_packet packet;
  20 +       int p_len = udhcp_get_payload_len(payload);
  21
  22         fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IP));
  23         if (fd < 0) {
  24 @@ -127,6 +132,7 @@
  25
  26         memset(&dest, 0, sizeof(dest));
  27         memset(&packet, 0, sizeof(packet));
  28 +       memcpy(&(packet.data), payload, p_len);
  29
  30         dest.sll_family = AF_PACKET;
  31         dest.sll_protocol = htons(ETH_P_IP);
  32 @@ -144,12 +150,13 @@
  33         packet.ip.daddr = dest_ip;
  34         packet.udp.source = htons(source_port);
  35         packet.udp.dest = htons(dest_port);
  36 -       packet.udp.len = htons(sizeof(packet.udp) + sizeof(struct dhcpMessage)); /* cheat on the psuedo-header */
  37 +       p_len += sizeof(packet.udp);
  38 +       packet.udp.len = htons(p_len);
  39         packet.ip.tot_len = packet.udp.len;
  40 -       memcpy(&(packet.data), payload, sizeof(struct dhcpMessage));
  41 -       packet.udp.check = udhcp_checksum(&packet, sizeof(struct udp_dhcp_packet));
  42 +       p_len += sizeof(packet.ip);
  43 +       packet.udp.check = udhcp_checksum(&packet, p_len);
  44
  45 -       packet.ip.tot_len = htons(sizeof(struct udp_dhcp_packet));
  46 +       packet.ip.tot_len = htons(p_len);
  47         packet.ip.ihl = sizeof(packet.ip) >> 2;
  48         packet.ip.version = IPVERSION;
  49         packet.ip.ttl = IPDEFTTL;
  50 @@ -158,7 +165,7 @@
  51         if (sizeof(struct udp_dhcp_packet) != 576)
  52                 BUG_sizeof_struct_udp_dhcp_packet_must_be_576();
  53
  54 -       result = sendto(fd, &packet, sizeof(struct udp_dhcp_packet), 0,
  55 +       result = sendto(fd, &packet, p_len, 0,
  56                         (struct sockaddr *) &dest, sizeof(dest));
  57         if (result <= 0) {
  58                 bb_perror_msg("sendto");
  59 @@ -205,7 +212,7 @@
  60                 return -1;
  61         }
  62
  63 -       result = write(fd, payload, sizeof(struct dhcpMessage));
  64 +       result = write(fd, payload, udhcp_get_payload_len(payload));
  65         close(fd);
  66         return result;
  67  }
  68 Index: busybox-1.4.2/networking/udhcp/common.h
  69 ===================================================================
  70 --- busybox-1.4.2.orig/networking/udhcp/common.h        2007-06-04 13:21:32.297066768 +0200
  71 +++ busybox-1.4.2/networking/udhcp/common.h     2007-06-04 13:21:33.620865520 +0200
  72 @@ -22,6 +22,8 @@
  73  #include <netinet/udp.h>
  74  #include <netinet/ip.h>
  75
  76 +#define MAX_OPTIONS_LEN  308
  77 +
  78  struct dhcpMessage {
  79         uint8_t op;
  80         uint8_t htype;
  81 @@ -38,7 +40,7 @@
  82         uint8_t sname[64];
  83         uint8_t file[128];
  84         uint32_t cookie;
  85 -       uint8_t options[308]; /* 312 - cookie */
  86 +       uint8_t options[MAX_OPTIONS_LEN]; /* 312 - cookie */
  87  };
  88
  89  struct udp_dhcp_packet {