diff options
| -rw-r--r-- | src/network/lookup_name.c | 42 |
1 files changed, 41 insertions, 1 deletions
diff --git a/src/network/lookup_name.c b/src/network/lookup_name.c index fb7b5c12..09734b50 100644 --- a/src/network/lookup_name.c +++ b/src/network/lookup_name.c @@ -157,6 +157,46 @@ static int name_from_dns(struct address buf[static MAXADDRS], char canon[static return EAI_FAIL; } +static int name_from_dns_search(struct address buf[static MAXADDRS], char canon[static 256], const char *name, int family) +{ + char search[256]; + struct resolvconf conf; + size_t l, dots; + char *p, *z; + + if (__get_resolv_conf(&conf, search, sizeof search) < 0) return -1; + + /* Count dots, suppress search when >=ndots or name ends in + * a dot, which is an explicit request for global scope. */ + for (dots=l=0; name[l]; l++) if (name[l]=='.') dots++; + if (dots >= conf.ndots || name[l-1]=='.') *search = 0; + + /* This can never happen; the caller already checked length. */ + if (l >= 256) return EAI_NONAME; + + /* Name with search domain appended is setup in canon[]. This both + * provides the desired default canonical name (if the requested + * name is not a CNAME record) and serves as a buffer for passing + * the full requested name to name_from_dns. */ + memcpy(canon, name, l); + canon[l] = '.'; + + for (p=search; *p; p=z) { + for (; isspace(*p); p++); + for (z=p; *z && !isspace(*z); z++); + if (z==p) break; + if (z-p < 256 - l - 1) { + memcpy(canon+l+1, p, z-p); + canon[z-p+1+l] = 0; + int cnt = name_from_dns(buf, canon, canon, family); + if (cnt) return cnt; + } + } + + canon[l] = 0; + return name_from_dns(buf, canon, name, family); +} + static const struct policy { unsigned char addr[16]; unsigned char len, mask; @@ -257,7 +297,7 @@ int __lookup_name(struct address buf[static MAXADDRS], char canon[static 256], c if (!cnt) cnt = name_from_numeric(buf, name, family); if (!cnt && !(flags & AI_NUMERICHOST)) { cnt = name_from_hosts(buf, canon, name, family); - if (!cnt) cnt = name_from_dns(buf, canon, name, family); + if (!cnt) cnt = name_from_dns_search(buf, canon, name, family); } if (cnt<=0) return cnt ? cnt : EAI_NONAME; |