libdb/uIP/uip_icmp.c

   1 #include <stdlib.h>
   2 #include <string.h>
   3
   4 #include "uip_ip.h"
   5 #include "uip_pbuf.h"
   6 #include "uip_netif.h"
   7 #include "uip_icmp.h"
   8
   9 #if UIP_LOGGING == 1
  10 #include <stdio.h>
  11 #define UIP_LOG(m) uip_log(__FILE__,__LINE__,m)
  12 #else
  13 #define UIP_LOG(m)
  14 #endif /* UIP_LOGGING == 1 */
  15
  16 #if UIP_STATISTICS == 1
  17 struct uip_stats uip_stat;
  18 #define UIP_STAT(s) s
  19 #else
  20 #define UIP_STAT(s)
  21 #endif /* UIP_STATISTICS == 1 */
  22
  23 void uip_icmpinput(struct uip_pbuf *p,struct uip_netif *inp)
  24 {
  25         u8_t code,type;
  26         u16_t hlen;
  27         struct uip_ip_addr tmpaddr;
  28         struct uip_ip_hdr *iphdr;
  29         struct uip_icmp_echo_hdr *iecho;
  30
  31         iphdr = p->payload;
  32         hlen = UIP_IPH_HL(iphdr)*4;
  33         if(uip_pbuf_header(p,-((s16_t)hlen)) || p->tot_len<sizeof(u16_t)*2) {
  34                 UIP_LOG("uip_icmpinput: short ICMP received.\n");
  35                 uip_pbuf_free(p);
  36                 return;
  37         }
  38
  39         type = *((u8_t*)p->payload);
  40         code = *((u8_t*)p->payload+1);
  41         switch(type) {
  42                 case UIP_ICMP_ECHO:
  43                         if(ip_addr_isbroadcast(&iphdr->dst,inp) || ip_addr_ismulticast(&iphdr->dst)) {
  44                                 UIP_LOG("uip_icmpinput: Not echoing to broadcast pings.\n");
  45                                 uip_pbuf_free(p);
  46                                 return;
  47                         }
  48
  49                         if(p->tot_len<sizeof(struct uip_icmp_echo_hdr)) {
  50                                 UIP_LOG("uip_icmpinput: bad ICMP echo received.\n");
  51                                 uip_pbuf_free(p);
  52                                 return;
  53                         }
  54
  55                         iecho = p->payload;
  56                         if(uip_ipchksum_pbuf(p)!=0) {
  57                                 UIP_LOG("uip_icmpinput: checksum failed for received ICMP echo.\n");
  58                                 uip_pbuf_free(p);
  59                                 return;
  60                         }
  61
  62                         tmpaddr.addr = iphdr->src.addr;
  63                         iphdr->src.addr = iphdr->dst.addr;
  64                         iphdr->dst.addr = tmpaddr.addr;
  65                         UIP_ICMPH_TYPE_SET(iecho,UIP_ICMP_ER);
  66
  67                         if(iecho->chksum>=htons(0xffff-(UIP_ICMP_ECHO<<8))) iecho->chksum += htons(UIP_ICMP_ECHO<<8)+1;
  68                         else iecho->chksum += htons(UIP_ICMP_ECHO<<8);
  69
  70                         uip_pbuf_header(p,hlen);
  71                         uip_ipoutput_if(p,&iphdr->src,NULL,UIP_IPH_TTL(iphdr),0,UIP_PROTO_ICMP,inp);
  72                         break;
  73                 default:
  74                         UIP_LOG("uip_icmpinput: ICMP type/code not supported.\n");
  75                         break;
  76         }
  77         uip_pbuf_free(p);
  78 }
  79
  80 void uip_icmp_destunreach(struct uip_pbuf *p,enum uip_icmp_dur_type t)
  81 {
  82         struct uip_pbuf *q;
  83         struct uip_ip_hdr *iphdr;
  84         struct uip_icmp_dur_hdr *idur;
  85
  86         q = uip_pbuf_alloc(UIP_PBUF_IP,sizeof(struct uip_icmp_dur_hdr)+UIP_IP_HLEN+8,UIP_PBUF_RAM);
  87
  88         iphdr = p->payload;
  89         idur = q->payload;
  90
  91         UIP_ICMPH_TYPE_SET(idur,UIP_ICMP_DUR);
  92         UIP_ICMPH_CODE_SET(idur,t);
  93
  94         UIP_MEMCPY((u8_t*)q->payload+sizeof(struct uip_icmp_dur_hdr),p->payload,UIP_IP_HLEN+8);
  95
  96         idur->chksum = 0;
  97         idur->chksum = uip_ipchksum(idur,q->len);
  98
  99         uip_ipoutput(q,NULL,&iphdr->src,UIP_ICMP_TTL,0,UIP_PROTO_ICMP);
 100         uip_pbuf_free(q);
 101 }