From 8ed8e5cae841e650e9528a9d5390327adbca68e7 Mon Sep 17 00:00:00 2001 From: Elizabeth Myers Date: Wed, 23 Mar 2016 16:40:31 -0500 Subject: [PATCH] res: expose rDNS building functions This will be used by the blacklist code to avoid duplication of code. --- authd/res.c | 81 +++++++++++++++++++++++++++++++---------------------- authd/res.h | 1 + 2 files changed, 48 insertions(+), 34 deletions(-) diff --git a/authd/res.c b/authd/res.c index f9db7afd..d68e402a 100644 --- a/authd/res.c +++ b/authd/res.c @@ -465,6 +465,52 @@ static void do_query_name(struct DNSQuery *query, const char *name, struct resli query_name(request); } +/* Build an rDNS style query - if suffix is NULL, use the appropriate .arpa zone */ +void build_rdns(char *buf, size_t size, const struct rb_sockaddr_storage *addr, const char *suffix) +{ + const unsigned char *cp; + + if (GET_SS_FAMILY(addr) == AF_INET) + { + const struct sockaddr_in *v4 = (const struct sockaddr_in *)addr; + cp = (const unsigned char *)&v4->sin_addr.s_addr; + + (void) snprintf(buf, size, "%u.%u.%u.%u.%s", + (unsigned int)(cp[3]), + (unsigned int)(cp[2]), + (unsigned int)(cp[1]), + (unsigned int)(cp[0]), + suffix == NULL ? "in-addr.arpa" : suffix); + } +#ifdef RB_IPV6 + else if (GET_SS_FAMILY(addr) == AF_INET6) + { + const struct sockaddr_in6 *v6 = (const struct sockaddr_in6 *)addr; + cp = (const unsigned char *)&v6->sin6_addr.s6_addr; + + (void) snprintf(buf, size, + "%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%s", + (unsigned int)(cp[15] & 0xf), (unsigned int)(cp[15] >> 4), + (unsigned int)(cp[14] & 0xf), (unsigned int)(cp[14] >> 4), + (unsigned int)(cp[13] & 0xf), (unsigned int)(cp[13] >> 4), + (unsigned int)(cp[12] & 0xf), (unsigned int)(cp[12] >> 4), + (unsigned int)(cp[11] & 0xf), (unsigned int)(cp[11] >> 4), + (unsigned int)(cp[10] & 0xf), (unsigned int)(cp[10] >> 4), + (unsigned int)(cp[9] & 0xf), (unsigned int)(cp[9] >> 4), + (unsigned int)(cp[8] & 0xf), (unsigned int)(cp[8] >> 4), + (unsigned int)(cp[7] & 0xf), (unsigned int)(cp[7] >> 4), + (unsigned int)(cp[6] & 0xf), (unsigned int)(cp[6] >> 4), + (unsigned int)(cp[5] & 0xf), (unsigned int)(cp[5] >> 4), + (unsigned int)(cp[4] & 0xf), (unsigned int)(cp[4] >> 4), + (unsigned int)(cp[3] & 0xf), (unsigned int)(cp[3] >> 4), + (unsigned int)(cp[2] & 0xf), (unsigned int)(cp[2] >> 4), + (unsigned int)(cp[1] & 0xf), (unsigned int)(cp[1] >> 4), + (unsigned int)(cp[0] & 0xf), (unsigned int)(cp[0] >> 4), + suffix == NULL ? "ip6.arpa" : suffix); + } +#endif +} + /* * do_query_number - Use this to do reverse IP# lookups. */ @@ -480,40 +526,7 @@ static void do_query_number(struct DNSQuery *query, const struct rb_sockaddr_sto request->name = (char *)rb_malloc(IRCD_RES_HOSTLEN + 1); } - if (GET_SS_FAMILY(addr) == AF_INET) - { - const struct sockaddr_in *v4 = (const struct sockaddr_in *)addr; - cp = (const unsigned char *)&v4->sin_addr.s_addr; - - sprintf(request->queryname, "%u.%u.%u.%u.in-addr.arpa", (unsigned int)(cp[3]), - (unsigned int)(cp[2]), (unsigned int)(cp[1]), (unsigned int)(cp[0])); - } -#ifdef RB_IPV6 - else if (GET_SS_FAMILY(addr) == AF_INET6) - { - const struct sockaddr_in6 *v6 = (const struct sockaddr_in6 *)addr; - cp = (const unsigned char *)&v6->sin6_addr.s6_addr; - - (void)sprintf(request->queryname, "%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x." - "%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.ip6.arpa", - (unsigned int)(cp[15] & 0xf), (unsigned int)(cp[15] >> 4), - (unsigned int)(cp[14] & 0xf), (unsigned int)(cp[14] >> 4), - (unsigned int)(cp[13] & 0xf), (unsigned int)(cp[13] >> 4), - (unsigned int)(cp[12] & 0xf), (unsigned int)(cp[12] >> 4), - (unsigned int)(cp[11] & 0xf), (unsigned int)(cp[11] >> 4), - (unsigned int)(cp[10] & 0xf), (unsigned int)(cp[10] >> 4), - (unsigned int)(cp[9] & 0xf), (unsigned int)(cp[9] >> 4), - (unsigned int)(cp[8] & 0xf), (unsigned int)(cp[8] >> 4), - (unsigned int)(cp[7] & 0xf), (unsigned int)(cp[7] >> 4), - (unsigned int)(cp[6] & 0xf), (unsigned int)(cp[6] >> 4), - (unsigned int)(cp[5] & 0xf), (unsigned int)(cp[5] >> 4), - (unsigned int)(cp[4] & 0xf), (unsigned int)(cp[4] >> 4), - (unsigned int)(cp[3] & 0xf), (unsigned int)(cp[3] >> 4), - (unsigned int)(cp[2] & 0xf), (unsigned int)(cp[2] >> 4), - (unsigned int)(cp[1] & 0xf), (unsigned int)(cp[1] >> 4), - (unsigned int)(cp[0] & 0xf), (unsigned int)(cp[0] >> 4)); - } -#endif + build_rdns(request->queryname, IRCD_RES_HOSTLEN + 1, addr, NULL); request->type = T_PTR; query_name(request); diff --git a/authd/res.h b/authd/res.h index 5a177257..1fabe0b2 100644 --- a/authd/res.h +++ b/authd/res.h @@ -32,5 +32,6 @@ extern void init_resolver(void); extern void restart_resolver(void); extern void gethost_byname_type(const char *, struct DNSQuery *, int); extern void gethost_byaddr(const struct rb_sockaddr_storage *, struct DNSQuery *); +extern void build_rdns(char *, size_t, const struct rb_sockaddr_storage *, const char *); #endif