diff options
Diffstat (limited to 'resolv/resolv-internal.h')
| -rw-r--r-- | resolv/resolv-internal.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/resolv/resolv-internal.h b/resolv/resolv-internal.h index d35df1c..0d69ce1 100644 --- a/resolv/resolv-internal.h +++ b/resolv/resolv-internal.h @@ -38,4 +38,22 @@ res_use_inet6 (void) return _res.options & DEPRECATED_RES_USE_INET6; } +enum + { + /* The advertized EDNS buffer size. The value 1200 is derived + from the IPv6 minimum MTU (1280 bytes) minus some arbitrary + space for tunneling overhead. If the DNS server does not react + to ICMP Fragmentation Needed But DF Set messages, this should + avoid all UDP fragments on current networks. Avoiding UDP + fragments is desirable because it prevents fragmentation-based + spoofing attacks because the randomness in a DNS packet is + concentrated in the first fragment (with the headers) and does + not protect subsequent fragments. */ + RESOLV_EDNS_BUFFER_SIZE = 1200, + }; + +/* Add an OPT record to a DNS query. */ +int __res_nopt (res_state, int n0, unsigned char *buf, int buflen, + int anslen) attribute_hidden; + #endif /* _RESOLV_INTERNAL_H */ |