diff options
| -rw-r--r-- | ip.c | 18 | ||||
| -rw-r--r-- | ip.h | 2 |
2 files changed, 14 insertions, 6 deletions
@@ -12,6 +12,7 @@ * Author: Stefano Brivio <sbrivio@redhat.com> */ +#include <assert.h> #include <stddef.h> #include <netinet/in.h> @@ -74,7 +75,7 @@ found: * ipproto_name() - Get IP protocol name from number * @proto: IP protocol number * - * Return: pointer to name of protocol @proto + * Return: pointer to name of protocol @proto (<= IPPROTO_STRLEN bytes) * * Usually this would be done with getprotobynumber(3) but that reads * /etc/protocols and might allocate, which isn't possible for us once @@ -83,16 +84,21 @@ found: const char *ipproto_name(uint8_t proto) { switch (proto) { +#define CASE(s) \ + static_assert(sizeof(s) <= IPPROTO_STRLEN, \ + "Increase IPPROTO_STRLEN to contain " #s); \ + return s; case IPPROTO_ICMP: - return "ICMP"; + CASE("ICMP"); case IPPROTO_TCP: - return "TCP"; + CASE("TCP"); case IPPROTO_UDP: - return "UDP"; + CASE("UDP"); case IPPROTO_ICMPV6: - return "ICMPv6"; + CASE("ICMPv6"); default: - return "<unknown protocol>"; + CASE("<unknown protocol>"); +#undef CASE } } @@ -118,6 +118,8 @@ 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); + +#define IPPROTO_STRLEN (sizeof("<unknown protocol>")) const char *ipproto_name(uint8_t proto); /* IPv6 link-local all-nodes multicast address, ff02::1 */ |