Re: [PATCH v3 06/14] ip: Add ipproto_name() function

[Laurent Vivier <lvivier@redhat.com>]

On 1/8/26 03:29, David Gibson wrote:
> Add a function to get the name of an IP protocol from its number.  Usually
> this would be done by getprotobynumber(), but that requires access to
> /etc/protocols and might allocate.  We can't do either of those once we've
> self-isolated.
> 
> Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
> ---
>   ip.c | 27 +++++++++++++++++++++++++++
>   ip.h |  2 ++
>   2 files changed, 29 insertions(+)
> 
> diff --git a/ip.c b/ip.c
> index 9a7f4c54..f1d224bd 100644
> --- a/ip.c
> +++ b/ip.c
> @@ -67,3 +67,30 @@ found:
>   	*proto = nh;
>   	return true;
>   }
> +
> +/**
> + * ipproto_name() - Get IP protocol name from number
> + * @proto:	IP protocol number
> + *
> + * Return: pointer to name of protocol @proto
> + *
> + * Usually this would be done with getprotobynumber(3) but that reads
> + * /etc/protocols and might allocate, which isn't possible for us once
> + * self-isolated.
> + */
> +/* cppcheck-suppress unusedFunction */
> +const char *ipproto_name(uint8_t proto)
> +{
> +	switch (proto) {
> +	case IPPROTO_ICMP:
> +		return "ICMP";
> +	case IPPROTO_TCP:
> +		return "TCP";
> +	case IPPROTO_UDP:
> +		return "UDP";
> +	case IPPROTO_ICMPV6:
> +		return "ICMPv6";
> +	default:
> +		return "<unknown protocol>";
> +	}
> +}
> diff --git a/ip.h b/ip.h
> index 5830b923..42b417c5 100644
> --- a/ip.h
> +++ b/ip.h
> @@ -116,6 +116,7 @@ static inline uint32_t ip6_get_flow_lbl(const struct ipv6hdr *ip6h)
>   }
>   
>   bool ipv6_l4hdr(struct iov_tail *data, uint8_t *proto, size_t *dlen);
> +const char *ipproto_name(uint8_t proto);
>   
>   /* IPv6 link-local all-nodes multicast address, ff02::1 */
>   static const struct in6_addr in6addr_ll_all_nodes = {
> @@ -135,4 +136,5 @@ static const struct in_addr in4addr_broadcast = { 0xffffffff };
>   #define IPV6_MIN_MTU		1280
>   #endif
>   
> +

Extra blank line
>   #endif /* IP_H */

Reviewed-by: Laurent Vivier <lvivier@redhat.com>