Indeed they are readable.
They are located within the region pointed to by skb->data
more specifically:
u32 someaddr = ((struct iphdr *) (skb->data + sizeof(struct ethhdr))->saddr; //if I remember correctly
......Assuming you're reading the packet directly from the network card.
Otherwise, skb->data may be moved up by a header or two.
For example, if you're inside the IP receive functions, the pointer will be moved up by sizeof(struct ethhdr) bytes.
At 07:50 AM 4/10/2005, linux lover wrote:
hello, Does skbuffs provide facility to access other layers headers at any layer? What i want, if packet is processed at LINK layer then can IP addresses(SRC & DST) of packets is readable at Link layer?
regards, linux_lover.
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