X-Git-Url: http://gitweb.fperrin.net/?a=blobdiff_plain;f=iftop.c;h=562a45bd33b719b9a5b77e85fa3001748c2c558a;hb=05a5759674e8e7124984579c67b7bea40b8e3352;hp=a090dcf84a18e63b7b4f74f9a1e6c6268753d7e2;hpb=626b3a3ea024fcad4111b93e9b527119a0e882dd;p=iftop.git

diff --git a/iftop.c b/iftop.c
index a090dcf..562a45b 100644
--- a/iftop.c
+++ b/iftop.c
@@ -109,6 +109,8 @@ history_type* history_create() {
 
 void history_rotate() {
     hash_node_type* n = NULL;
+    struct pcap_stat ps;
+
     history_pos = (history_pos + 1) % HISTORY_LENGTH;
     hash_next_item(history, &n);
     while(n != NULL) {
@@ -134,6 +136,9 @@ void history_rotate() {
     if(history_len < HISTORY_LENGTH) {
         history_len++;
     }
+
+    pcap_stats(pd, &ps);
+    history_totals.lost_packets = ps.ps_drop + ps.ps_ifdrop;
 }
 
 
@@ -249,16 +254,16 @@ void assign_addr_pair(addr_pair* ap, struct ip* iptr, int flip) {
   }
 }
 
-static void handle_ip_packet(struct ip* iptr, int hw_dir)
+static void handle_ip_packet(struct ip* iptr, int hw_dir, int pld_len)
 {
     int direction = 0; /* incoming */
+    int len;
     history_type* ht;
     union {
       history_type **ht_pp;
       void **void_pp;
     } u_ht = { &ht };
     addr_pair ap;
-    unsigned int len = 0;
     struct in6_addr scribdst;   /* Scratch pad. */
     struct in6_addr scribsrc;   /* Scratch pad. */
     /* Reinterpret packet type. */
@@ -268,7 +273,21 @@ static void handle_ip_packet(struct ip* iptr, int hw_dir)
 
     tick(0);
 
-    if( (IP_V(iptr) ==4 && options.netfilter == 0)
+    /*
+     * Sanity check: drop obviously short packets.
+     * pld_len comes from pcaphdr->len - sizeof(struct l2_header).
+     *
+     * It is assumed that the snaplen (currently hard-coded to 1000) is
+     * big enough to always capture the IP header past the L2 encap, and
+     * that pcap never truncates the packet to less than snaplen; in
+     * other words, that pcaphdr->caplen = MIN(pcaphdr->len, snaplen).
+     */
+    if (pld_len < sizeof (struct ip))
+	return;
+    if (IP_V(iptr) == 6 && pld_len < sizeof (struct ip6_hdr))
+	return;
+
+    if( (IP_V(iptr) == 4 && options.netfilter == 0)
             || (IP_V(iptr) == 6 && options.netfilter6 == 0) ) { 
         /*
          * Net filter is off, so assign direction based on MAC address
@@ -424,21 +443,22 @@ static void handle_ip_packet(struct ip* iptr, int hw_dir)
           break;
     }
 
-
     if(hash_find(history, &ap, u_ht.void_pp) == HASH_STATUS_KEY_NOT_FOUND) {
         ht = history_create();
         hash_insert(history, &ap, ht);
     }
 
     /* Do accounting. */
-    switch (IP_V(iptr)) {
-      case 4:
-          len = ntohs(iptr->ip_len);
-          break;
-      case 6:
-          len = ntohs(ip6tr->ip6_plen) + 40;
+    switch (options.bandwidth_unit) {
+      case OPTION_BW_BITS:
+      case OPTION_BW_BYTES:
+	  len = pld_len;
+	  break;
+      case OPTION_BW_PKTS:
+	  len = 1;
+	  break;
       default:
-          break;
+	  return;
     }
 
     /* Update record */
@@ -468,7 +488,7 @@ static void handle_ip_packet(struct ip* iptr, int hw_dir)
 
 static void handle_raw_packet(unsigned char* args, const struct pcap_pkthdr* pkthdr, const unsigned char* packet)
 {
-    handle_ip_packet((struct ip*)packet, -1);
+    handle_ip_packet((struct ip*)packet, -1, pkthdr->len);
 }
 
 #ifdef DLT_PFLOG
@@ -482,18 +502,19 @@ static void handle_pflog_packet(unsigned char* args, const struct pcap_pkthdr* p
 	hdrlen = BPF_WORDALIGN(hdr->length);
 	length -= hdrlen;
 	packet += hdrlen;
-	handle_ip_packet((struct ip*)packet, -1);
+	handle_ip_packet((struct ip*)packet, -1, length);
 }
 #endif
 
 static void handle_null_packet(unsigned char* args, const struct pcap_pkthdr* pkthdr, const unsigned char* packet)
 {
-    handle_ip_packet((struct ip*)(packet + 4), -1);
+    handle_ip_packet((struct ip*)(packet + 4), -1, pkthdr->len);
 }
 
-static void handle_llc_packet(const struct llc* llc, int dir) {
-
-    struct ip* ip = (struct ip*)((void*)llc + sizeof(struct llc));
+static void handle_llc_packet(const struct llc* llc, int dir, int llclen) {
+    int hdrlen = sizeof(struct llc);
+    int pldlen = llclen - hdrlen;
+    struct ip* ip = (struct ip*)((void*)llc + hdrlen);
 
     /* Taken from tcpdump/print-llc.c */
     if(llc->ssap == LLCSAP_SNAP && llc->dsap == LLCSAP_SNAP
@@ -505,11 +526,11 @@ static void handle_llc_packet(const struct llc* llc, int dir) {
         switch(orgcode) {
           case OUI_ENCAP_ETHER:
           case OUI_CISCO_90:
-            handle_ip_packet(ip, dir);
+	      handle_ip_packet(ip, dir, pldlen);
             break;
           case OUI_APPLETALK:
             if(et == ETHERTYPE_ATALK) {
-              handle_ip_packet(ip, dir);
+		handle_ip_packet(ip, dir, pldlen);
             }
             break;
           default:;
@@ -521,52 +542,55 @@ static void handle_llc_packet(const struct llc* llc, int dir) {
 static void handle_tokenring_packet(unsigned char* args, const struct pcap_pkthdr* pkthdr, const unsigned char* packet)
 {
     struct token_header *trp;
+    int hdrlen = 0;
     int dir = -1;
     trp = (struct token_header *)packet;
 
     if(IS_SOURCE_ROUTED(trp)) {
-      packet += RIF_LENGTH(trp);
+      hdrlen += RIF_LENGTH(trp);
     }
-    packet += TOKEN_HDRLEN;
+    hdrlen += TOKEN_HDRLEN;
+    packet += hdrlen;
 
     if(memcmp(trp->token_shost, if_hw_addr, 6) == 0 ) {
       /* packet leaving this i/f */
       dir = 1;
-    } 
-        else if(memcmp(trp->token_dhost, if_hw_addr, 6) == 0 || memcmp("\xFF\xFF\xFF\xFF\xFF\xFF", trp->token_dhost, 6) == 0) {
+    }
+    else if(memcmp(trp->token_dhost, if_hw_addr, 6) == 0 || memcmp("\xFF\xFF\xFF\xFF\xFF\xFF", trp->token_dhost, 6) == 0) {
       /* packet entering this i/f */
       dir = 0;
     }
 
     /* Only know how to deal with LLC encapsulated packets */
     if(FRAME_TYPE(trp) == TOKEN_FC_LLC) {
-      handle_llc_packet((struct llc*)packet, dir);
+	handle_llc_packet((struct llc*)packet, dir, pkthdr->len - hdrlen);
     }
 }
 
 static void handle_ppp_packet(unsigned char* args, const struct pcap_pkthdr* pkthdr, const unsigned char* packet)
 {
-	register u_int length = pkthdr->len;
-	register u_int caplen = pkthdr->caplen;
-	u_int proto;
+    register u_int length = pkthdr->len;
+    register u_int caplen = pkthdr->caplen;
+    u_int proto;
 
-	if (caplen < 2) 
-        return;
+    if (caplen < 2)
+	return;
 
-	if(packet[0] == PPP_ADDRESS) {
-		if (caplen < 4) 
-            return;
+    if(packet[0] == PPP_ADDRESS) {
+	if (caplen < 4)
+	    return;
 
-		packet += 2;
-		length -= 2;
+	packet += 2;
+	length -= 2;
 
-		proto = EXTRACT_16BITS(packet);
-		packet += 2;
-		length -= 2;
+	proto = EXTRACT_16BITS(packet);
+	packet += 2;
+	length -= 2;
 
-        if(proto == PPP_IP || proto == ETHERTYPE_IP || proto == ETHERTYPE_IPV6) {
-            handle_ip_packet((struct ip*)packet, -1);
-        }
+	if(proto == PPP_IP || proto == ETHERTYPE_IP
+	   || proto == ETHERTYPE_IPV6) {
+	    handle_ip_packet((struct ip*)packet, -1, length);
+	}
     }
 }
 
@@ -588,24 +612,25 @@ static void handle_cooked_packet(unsigned char *args, const struct pcap_pkthdr *
 	dir=1;
 	break;
     }
-    handle_ip_packet((struct ip*)(packet+SLL_HDR_LEN), dir);
+    handle_ip_packet((struct ip*)(packet+SLL_HDR_LEN), dir,
+		     thdr->len - SLL_HDR_LEN);
 }
 #endif /* DLT_LINUX_SLL */
 
 static void handle_eth_packet(unsigned char* args, const struct pcap_pkthdr* pkthdr, const unsigned char* packet)
 {
     struct ether_header *eptr;
-    int ether_type;
-    const unsigned char *payload;
+    int ether_type, hdrlen;
+
     eptr = (struct ether_header*)packet;
     ether_type = ntohs(eptr->ether_type);
-    payload = packet + sizeof(struct ether_header);
+    hdrlen = sizeof(struct ether_header);
 
     if(ether_type == ETHERTYPE_8021Q) {
         struct vlan_8021q_header* vptr;
-        vptr = (struct vlan_8021q_header*)payload;
+        vptr = (struct vlan_8021q_header*) (packet + hdrlen);
         ether_type = ntohs(vptr->ether_type);
-        payload += sizeof(struct vlan_8021q_header);
+        hdrlen += sizeof(struct vlan_8021q_header);
     }
 
     if(ether_type == ETHERTYPE_IP || ether_type == ETHERTYPE_IPV6) {
@@ -629,8 +654,8 @@ static void handle_eth_packet(unsigned char* args, const struct pcap_pkthdr* pkt
         }
 
         /* Distinguishing ip_hdr and ip6_hdr will be done later. */
-        iptr = (struct ip*)(payload); /* alignment? */
-        handle_ip_packet(iptr, dir);
+        iptr = (struct ip*) (packet + hdrlen); /* alignment? */
+        handle_ip_packet(iptr, dir, pkthdr->len - hdrlen);
     }
 }
 
@@ -643,7 +668,8 @@ static void handle_radiotap_packet(unsigned char* args, const struct pcap_pkthdr
 {
     /* 802.11 MAC header is = 34 bytes (not sure if that's universally true) */
     /* We could try harder to figure out hardware direction from the MAC header */
-    handle_ip_packet((struct ip*)(packet + ((struct radiotap_header *)packet)->it_len + 34),-1);
+    int hdrlen = ((struct radiotap_header *)packet)->it_len + 34;
+    handle_ip_packet((struct ip*)(packet + hdrlen), -1, pkthdr->len - hdrlen);
 }