DTrace IP Provider [PSARC/2008/302 FastTrack timeout 05/07/2008]

[Erik Nordmark]

Adam,

Overall this looks good. One nit though.

> /*
>  * ipinfo contains common IP info for both IPv4 and IPv6.
>  */
> typedef struct ipinfo {
>         uint8_t ip_ver;                 /* IP version (4, 6) */
>         uint16_t ip_plength;            /* payload length */
>         string ip_saddr;                /* source address */
>         string ip_daddr;                /* destination address */
> } ipinfo_t;

I don't think "payload length" has a natural definition when trying to 
look at what IP actually carries because of the IPv6 extension headers.
For instance, for a 100 byte IPv6 packet with a 8 byte hop-by-hop 
options header, a fragment header, and a TCP header, what is the payload 
length?
The IPv6 header field for payload length is just 40 less than the size 
of the IPv6 packet. But the payload that IP delivers to TCP is less all 
the extension headers. And some might think that "payload" refers to the 
TCP payload.

Thus I think it would be more clear to have the IP provider expose the 
IP packet length instead of payload length.

Sorry for not catching this earlier.

    Erik