vnet-module

diff -r c0b0974fb055 tools/vnet/vnet-module/esp.c
@@ -341,12 +341,12 @@
         dprintf("> ETH header pull...\n");
         memmove(skb->data, skb->mac.raw, ETH_HLEN);
         skb->mac.raw = skb->data; 
-        __skb_pull(skb, ETH_HLEN);
+        skb_pull_vn(skb, ETH_HLEN);
     }
     dprintf("> IP header pull...\n");
     memmove(skb->data, skb->nh.raw, ip_n);
     skb->nh.raw = skb->data;
-    __skb_pull(skb, ip_n);
+    skb_pull_vn(skb, ip_n);
     esph = (void*)skb->data;
     // Add spi and sequence number.
     esph->spi = sa->ident.spi;

@@ -457,7 +457,7 @@
     // Move skb->data back to ethernet header.
     // Do in 2 moves to ensure offsets are +ve,
     // since args to skb_pull/skb_push are unsigned.
-    __skb_pull(skb, head_n);
+    skb_pull_vn(skb, head_n);
     __skb_push(skb, skb->data - skb->mac.raw);
     // After this esph is invalid.
     esph = NULL;

@@ -763,7 +763,7 @@
     dprintf(">\n");
 #ifdef DEBUG
     dprintf("> recv skb=\n"); 
-    skb_print_bits(skb, 0, skb->len);
+    skb_print_bits("", skb, 0, skb->len);
 #endif
     ip_n = (skb->nh.iph->ihl << 2);
     if(skb->data == skb->mac.raw){

@@ -773,7 +773,7 @@
             err = -EINVAL;
             goto exit;
         }
-        skb_pull(skb, eth_n + ip_n);
+        skb_pull_vn(skb, eth_n + ip_n);
     }
     addr = skb->nh.iph->daddr;
     err = esp_skb_header(skb, &esph);

66 lines not on this page · raw message

diff -r c0b0974fb055 tools/vnet/vnet-module/skb_util.h
@@ -66,6 +66,21 @@
 }
 
 #endif
+
+/*
+ * It's a copy from {kernel}/include/linux/skbuff.h func '__skb_pull' and 'skb_pull'
+ * to aviodthe BUG_ON when pulling into the data (getting forwarded ip-frames)
+ */
+static inline unsigned char *__skb_pull_vn(struct sk_buff *skb, unsigned int len)
+{
+        skb->len -= len;
+        //BUG_ON(skb->len < skb->data_len);
+        return skb->data += len;
+}
+static inline unsigned char *skb_pull_vn(struct sk_buff *skb, unsigned int len)
+{
+        return unlikely(len > skb->len) ? NULL : __skb_pull_vn(skb, len);
+}
 
 
 #ifdef __KERNEL__

diff -r c0b0974fb055 tools/vnet/vnet-module/varp.c
@@ -1365,7 +1365,7 @@
             goto exit;
         }
     }
-    varph = (void*)skb_pull(skb, sizeof(struct udphdr));
+    varph = (void*)skb_pull_vn(skb, sizeof(struct udphdr));
     if(skb->len < sizeof(struct VnetMsgHdr)){
         wprintf("> Varp msg too short: %d < %d\n", skb->len, sizeof(struct VnetMsgHdr));
         goto exit;

@@ -1378,11 +1378,11 @@
         }
         break;
     case VUDP_ID: // Etherip-in-udp packet.
-        skb_pull(skb, sizeof(struct VnetMsgHdr));
+        skb_pull_vn(skb, sizeof(struct VnetMsgHdr));
         err = etherip_protocol_recv(skb);
         goto exit;
     case VFWD_ID: // Forwarded.
-        skb_pull(skb, sizeof(struct VnetMsgHdr));
+        skb_pull_vn(skb, sizeof(struct VnetMsgHdr));
         err = vnet_forward_recv(skb);
         goto exit;
     default:

diff -r c0b0974fb055 tools/vnet/vnet-module/vnet_forward.c
@@ -186,7 +186,7 @@
     printk("\nWrapped packet:\n");
     print_iphdr(__FUNCTION__, skb);
     print_udphdr(__FUNCTION__, skb);
-    skb_print_bits(__FUNCTION__, skb, 0, 0 * skb->len);
+    skb_print_bits(__FUNCTION__, skb, 0, skb->len);
 #endif
 
     err = _skb_xmit(skb, saddr);

@@ -304,7 +304,7 @@
     peer->rx_packets++;
     skb->mac.raw = NULL;
     skb->nh.raw = skb->data;
-    skb->h.raw = (void*)(skb->nh.iph + 1);
+    skb->h.raw = skb->data + sizeof(struct iphdr);
     if(!skb->nh.iph->saddr){
         skb->nh.iph->saddr = addr.u.ip4.s_addr;
     }

@@ -328,12 +328,17 @@
 
     // Handle (a copy of) it ourselves, because
     // if it is looped-back by xmit it will be ignored.
-    //recvskb = skb_clone(skb, GFP_ATOMIC);
-    recvskb = pskb_copy(skb, GFP_ATOMIC);
+    recvskb = alloc_skb(skb->len, GFP_ATOMIC);
     if(recvskb){
+        recvskb->protocol = htons(ETH_P_IP);
+
+        recvskb->nh.raw = skb_put(recvskb, skb->len);
+        recvskb->h.raw = recvskb->data + sizeof(struct iphdr); 
+        skb_copy_bits(skb, 0, recvskb->data, skb->len);
+        
         // Data points at the unwrapped iphdr, but varp_handle_message()
         // expects it to point at the udphdr, so pull.
-        skb_pull(recvskb, sizeof(struct iphdr));
+        skb_pull_vn(recvskb, sizeof(struct iphdr));
         if(varp_handle_message(recvskb) <= 0){
             kfree_skb(recvskb);
         }