From 499ca6a307a59454db8102c83fa8b31e5956886e Mon Sep 17 00:00:00 2001 From: leitner Date: Thu, 3 Jun 2004 16:31:27 +0000 Subject: [PATCH] also support ip6.arpa in addition to ip6.int --- CHANGES | 2 ++ dns.h | 6 ++++-- dns/dns_name.c | 15 +++++++++++---- dns/dns_name6.3 | 5 ++++- dns/dns_name6_domain.3 | 6 +++++- dns/dns_nd6.c | 13 +++++++++---- 6 files changed, 35 insertions(+), 12 deletions(-) diff --git a/CHANGES b/CHANGES index b33903a..6f08401 100644 --- a/CHANGES +++ b/CHANGES @@ -2,6 +2,8 @@ add errmsg API work around broken Linux sendfile API (offset 64-bit but count 32-bit) add io_appendfile, io_readwritefile + support ip6.arpa in addition to ip6.int in dns_name (adds one + parameter to dns_name6_domain and two constants in dns.h) 0.19.2: for some reason, a botched dependency slipped in the the Makefile diff --git a/dns.h b/dns.h index 0752a72..307c71c 100644 --- a/dns.h +++ b/dns.h @@ -87,7 +87,9 @@ int dns_ip4_qualify(stralloc *,stralloc *,const stralloc *); int dns_ip6_qualify_rules(stralloc *,stralloc *,const stralloc *,const stralloc *); int dns_ip6_qualify(stralloc *,stralloc *,const stralloc *); -int dns_name6_domain(char *,char *); -#define DNS_NAME6_DOMAIN (4*16+10) +#define DNS_IP6_INT 0 +#define DNS_IP6_ARPA 1 +int dns_name6_domain(char *,const char *,int); +#define DNS_NAME6_DOMAIN (4*16+11) #endif diff --git a/dns/dns_name.c b/dns/dns_name.c index 1f03186..de3e1cd 100644 --- a/dns/dns_name.c +++ b/dns/dns_name.c @@ -48,16 +48,23 @@ int dns_name4(stralloc *out,const char ip[4]) return 0; } -int dns_name6(stralloc *out,char ip[16]) +static int dns_name6_inner(stralloc *out,const char ip[16],int t) { char name[DNS_NAME6_DOMAIN]; - if (ip6_isv4mapped(ip)) - return dns_name4(out,ip+12); - dns_name6_domain(name,ip); + dns_name6_domain(name,ip,t); if (dns_resolve(name,DNS_T_PTR) == -1) return -1; if (dns_name_packet(out,dns_resolve_tx.packet,dns_resolve_tx.packetlen) == -1) return -1; dns_transmit_free(&dns_resolve_tx); dns_domain_free(&q); return 0; } + +int dns_name6(stralloc *out,const char ip[16]) +{ + if (ip6_isv4mapped(ip)) + return dns_name4(out,ip+12); + if (dns_name6_inner(out,ip,DNS_IP6_ARPA)) return -1; + if (!out->len) return dns_name6_inner(out,ip,DNS_IP6_INT); + return 0; +} diff --git a/dns/dns_name6.3 b/dns/dns_name6.3 index d169ec5..48ab759 100644 --- a/dns/dns_name6.3 +++ b/dns/dns_name6.3 @@ -11,7 +11,10 @@ puts the (first) domain name into \fIout\fR and returns 0. If the relevant ip6.int domain does not exist in DNS, or has no PTR records, \fIout\fR will be empty. -If dns_name4 has trouble with the DNS lookup or runs out of memory, it returns +dns_name6 will try both the new "ip6.arpa" reverse lookup domain and the +old (deprecated) "ip6.int" one. + +If dns_name6 has trouble with the DNS lookup or runs out of memory, it returns -1, setting errno appropriately. It may or may not change \fIout\fR. .SH "SEE ALSO" dns_name_packet(3), dns_name6_domain(3), dns_name4(3), dns_ip6(3) diff --git a/dns/dns_name6_domain.3 b/dns/dns_name6_domain.3 index f9d2114..455b867 100644 --- a/dns/dns_name6_domain.3 +++ b/dns/dns_name6_domain.3 @@ -5,11 +5,15 @@ dns_name6_domain \- construct host name for reverse lookup .B #include int \fBdns_name6_domain\fP(char \fIq\fR[DNS_NAME6_DOMAIN], - const char* \fIip\fR[16]); + const char* \fIip\fR[16],int \fItype\fR); .SH DESCRIPTION dns_name6_domain is a low-level component of dns_name6. It converts an IP address such as 4321:0:1:2:3:4:567:89ab into a domain name such as b.a.9.8.7.6.5.0.4.0.0.0.3.0.0.0.2.0.0.0.1.0.0.0.0.0.0.0.1.2.3.4.IP6.INT and places the packet-encoded domain name into \fIq\fR. + +\fItype\fR can be DNS_IP6_INT or DNS_IP6_ARPA. The "ip6.int" domain for +IPv6 reverse lookups is now deprecated and "ip6.arpa" is the standard +way. .SH "SEE ALSO" dns_name6(3), dns_name4_domain(3) diff --git a/dns/dns_nd6.c b/dns/dns_nd6.c index 0e61e51..0376a22 100644 --- a/dns/dns_nd6.c +++ b/dns/dns_nd6.c @@ -7,13 +7,14 @@ * 4321:0:1:2:3:4:567:89ab * -> * b.a.9.8.7.6.5.0.4.0.0.0.3.0.0.0.2.0.0.0.1.0.0.0.0.0.0.0.1.2.3.4.IP6.INT. + * b.a.9.8.7.6.5.0.4.0.0.0.3.0.0.0.2.0.0.0.1.0.0.0.0.0.0.0.1.2.3.4.IP6.ARPA. */ -static inline char tohex(char c) { +static char tohex(char c) { return c>=10?c-10+'a':c+'0'; } -int dns_name6_domain(char name[DNS_NAME6_DOMAIN],char ip[16]) +int dns_name6_domain(char name[DNS_NAME6_DOMAIN],const char ip[16],int t) { unsigned int j; @@ -23,7 +24,11 @@ int dns_name6_domain(char name[DNS_NAME6_DOMAIN],char ip[16]) name[j*4+2]=1; name[j*4+3]=tohex((unsigned char)ip[15-j] >> 4); } - byte_copy(name + 4*16,9,"\3ip6\3int\0"); - return 4*16+9; + if (t==DNS_IP6_INT) + byte_copy(name + 4*16,9,"\3ip6\3int\0"); + else if (t==DNS_IP6_ARPA) + byte_copy(name + 4*16,10,"\3ip6\4arpa\0"); + else return 0; + return 4*16+9+t; }