1 files changed, 91 insertions, 81 deletions

diff --git a/src/lib/libc/net/resolver.3 b/src/lib/libc/net/resolver.3
index 99abe17f03..e820ea25ed 100644
--- a/src/lib/libc/net/resolver.3
+++ b/src/lib/libc/net/resolver.3
@@ -1,4 +1,4 @@
-.\"     $NetBSD: resolver.3,v 1.5 1995/02/25 06:21:02 cgd Exp $
+.\"     $OpenBSD: resolver.3,v 1.21 2007/05/31 19:19:30 jmc Exp $
 .\"
 .\" Copyright (c) 1985, 1991, 1993
 .\"     The Regents of the University of California.  All rights reserved.
@@ -11,11 +11,7 @@
 .\" 2. Redistributions in binary form must reproduce the above copyright
 .\"    notice, this list of conditions and the following disclaimer in the
 .\"    documentation and/or other materials provided with the distribution.
-.\" 3. All advertising materials mentioning features or use of this software
-.\"    must display the following acknowledgement:
-.\"     This product includes software developed by the University of
-.\"     California, Berkeley and its contributors.
-.\" 4. Neither the name of the University nor the names of its contributors
+.\" 3. Neither the name of the University nor the names of its contributors
 .\"    may be used to endorse or promote products derived from this software
 .\"    without specific prior written permission.
 .\"
@@ -31,11 +27,9 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     @(#)resolver.3  8.1 (Berkeley) 6/4/93
-.\"
-.Dd June 4, 1993
+.Dd $Mdocdate: May 31 2007 $
 .Dt RESOLVER 3
-.Os BSD 4.3
+.Os
 .Sh NAME
 .Nm res_query ,
 .Nm res_search ,
@@ -50,69 +44,76 @@
 .Fd #include <netinet/in.h>
 .Fd #include <arpa/nameser.h>
 .Fd #include <resolv.h>
+.Ft int
 .Fo res_query
-.Fa "char *dname"
+.Fa "const char *dname"
 .Fa "int class"
 .Fa "int type"
-.Fa "u_char *answer"
+.Fa "unsigned char *answer"
 .Fa "int anslen"
 .Fc
+.Ft int
 .Fo res_search
-.Fa "char *dname"
+.Fa "const char *dname"
 .Fa "int class"
 .Fa "int type"
-.Fa "u_char *answer"
+.Fa "unsigned char *answer"
 .Fa "int anslen"
 .Fc
+.Ft int
 .Fo res_mkquery
 .Fa "int op"
-.Fa "char *dname"
+.Fa "const char *dname"
 .Fa "int class"
 .Fa "int type"
-.Fa "char *data"
+.Fa "const unsigned char *data"
 .Fa "int datalen"
-.Fa "struct rrec *newrr"
-.Fa "char *buf"
+.Fa "const unsigned char *newrr"
+.Fa "unsigned char *buf"
 .Fa "int buflen"
 .Fc
+.Ft int
 .Fo res_send
-.Fa "char *msg"
+.Fa "const unsigned char *msg"
 .Fa "int msglen"
-.Fa "char *answer"
+.Fa "unsigned char *answer"
 .Fa "int anslen"
 .Fc
-.Fn res_init 
+.Ft int
+.Fn res_init "void"
+.Ft int
 .Fo dn_comp
-.Fa "char *exp_dn"
-.Fa "char *comp_dn"
+.Fa "const char *exp_dn"
+.Fa "unsigned char *comp_dn"
 .Fa "int length"
-.Fa "char **dnptrs"
-.Fa "char **lastdnptr"
+.Fa "unsigned char **dnptrs"
+.Fa "unsigned char **lastdnptr"
 .Fc
+.Ft int
 .Fo dn_expand
-.Fa "u_char *msg"
-.Fa "u_char *eomorig"
-.Fa "u_char *comp_dn"
-.Fa "u_char *exp_dn"
+.Fa "const unsigned char *msg"
+.Fa "const unsigned char *eomorig"
+.Fa "const unsigned char *comp_dn"
+.Fa "char *exp_dn"
 .Fa "int length"
 .Fc
 .Sh DESCRIPTION
-These routines are used for making, sending and interpreting
+These routines are used for making, sending, and interpreting
 query and reply messages with Internet domain name servers.
 .Pp
 Global configuration and state information that is used by the
 resolver routines is kept in the structure
-.Em _res .
+.Li _res .
 Most of the values have reasonable defaults and can be ignored.
-Options
-stored in
-.Em _res.options
+Options stored in
+.Li _res.options
 are defined in
-.Pa resolv.h
+.Aq Pa resolv.h
 and are as follows.
-Options are stored as a simple bit mask containing the bitwise ``or''
+Options are stored as a simple bit mask containing the bitwise
+.Tn OR
 of the options enabled.
-.Bl -tag -width RES_DEFNAMES
+.Bl -tag -width RES_USE_INET6
 .It Dv RES_INIT
 True if the initial name server address and default domain name are
 initialized (i.e.,
@@ -137,8 +138,7 @@ Used with
 .Dv RES_USEVC
 to keep the
 .Tn TCP
-connection open between
-queries.
+connection open between queries.
 This is useful only in programs that regularly do many queries.
 .Tn UDP
 should be the normal mode used.
@@ -165,16 +165,28 @@ will search for host names in the current domain and in parent domains; see
 This is used by the standard host lookup routine
 .Xr gethostbyname 3 .
 This option is enabled by default.
+.It Dv RES_USE_INET6
+Enables support for IPv6-only applications.
+This causes IPv4 addresses to be returned as an IPv4 mapped address.
+For example, 10.1.1.1 will be returned as ::ffff:10.1.1.1.
+The option is not meaningful on
+.Ox .
+.It Dv RES_USE_EDNS0
+Enables support for OPT pseudo-RR for EDNS0 extension.
+With this option, resolver code will attach OPT pseudo-RR into DNS queries,
+to inform of our receive buffer size.
+The option will allow DNS servers to take advantage of non-default receive
+buffer size, and to send larger replies.
+DNS query packets with EDNS0 extension is not compatible with
+non-EDNS0 DNS servers.
 .El
 .Pp
 The
 .Fn res_init
-routine
-reads the configuration file (if any; see
+routine reads the configuration file (if any; see
 .Xr resolv.conf 5 )
-to get the default domain name,
-search list and
-the Internet address of the local name server(s).
+to get the default domain name, search list, and the Internet address
+of the local name server(s).
 If no server is configured, the host running
 the resolver is tried.
 The current domain name is defined by the hostname
@@ -212,20 +224,26 @@ The query requests information of the specified
 .Fa type
 and
 .Fa class
-for the specified fully-qualified domain name
+for the specified fully qualified domain name
 .Fa dname .
 The reply message is left in the
 .Fa answer
 buffer with length
 .Fa anslen
 supplied by the caller.
+Values for the
+.Fa class
+and
+.Fa type
+fields
+are defined in
+.Aq Pa arpa/nameser.h .
 .Pp
 The
 .Fn res_search
 routine makes a query and awaits a response like
 .Fn res_query ,
-but in addition, it implements the default and search rules
-controlled by the
+but in addition, it implements the default and search rules controlled by the
 .Dv RES_DEFNAMES
 and
 .Dv RES_DNSRCH
@@ -236,11 +254,9 @@ The remaining routines are lower-level routines used by
 .Fn res_query .
 The
 .Fn res_mkquery
-function
-constructs a standard query message and places it in
+function constructs a standard query message and places it in
 .Fa buf .
-It returns the size of the query, or \-1 if the query is
-larger than
+It returns the size of the query, or \-1 if the query is larger than
 .Fa buflen .
 The query type
 .Fa op
@@ -250,26 +266,23 @@ but can be any of the query types defined in
 .Aq Pa arpa/nameser.h .
 The domain name for the query is given by
 .Fa dname .
-.Fa Newrr
+.Fa newrr
 is currently unused but is intended for making update messages.
 .Pp
 The
 .Fn res_send
-routine
-sends a pre-formatted query and returns an answer.
+routine sends a pre-formatted query and returns an answer.
 It will call
 .Fn res_init
 if
 .Dv RES_INIT
 is not set, send the query to the local name server, and
 handle timeouts and retries.
-The length of the reply message is returned, or
-\-1 if there were errors.
+The length of the reply message is returned, or \-1 if there were errors.
 .Pp
 The
 .Fn dn_comp
-function
-compresses the domain name
+function compresses the domain name
 .Fa exp_dn
 and stores it in
 .Fa comp_dn .
@@ -278,24 +291,23 @@ The size of the array pointed to by
 .Fa comp_dn
 is given by
 .Fa length .
-The compression uses
-an array of pointers
+The compression uses an array of pointers
 .Fa dnptrs
-to previously-compressed names in the current message.
-The first pointer points to
+to previously compressed names in the current message.
+The first pointer points
 to the beginning of the message and the list ends with
 .Dv NULL .
 The limit to the array is specified by
 .Fa lastdnptr .
 A side effect of
 .Fn dn_comp
-is to update the list of pointers for
-labels inserted into the message
+is to update the list of pointers for labels inserted into the message
 as the name is compressed.
 If
-.Em dnptr
+.Fa dnptrs
 is
-.Dv NULL, names are not compressed.
+.Dv NULL ,
+names are not compressed.
 If
 .Fa lastdnptr
 is
@@ -304,10 +316,9 @@ the list of labels is not updated.
 .Pp
 The
 .Fn dn_expand
-entry
-expands the compressed domain name
+entry expands the compressed domain name
 .Fa comp_dn
-to a full domain name
+to a full domain name.
 The compressed name is contained in a query or reply message;
 .Fa msg
 is a pointer to the beginning of the message.
@@ -317,28 +328,27 @@ which is of size
 .Fa length .
 The size of compressed name is returned or \-1 if there was an error.
 .Sh FILES
-.Bl -tag -width Pa
-/etc/resolv.conf
-The configuration file
-see
-.Xr resolv.conf 5 .
+.Bl -tag -width "/etc/resolv.confXX"
+.It Pa /etc/resolv.conf
+The configuration file.
 .El
 .Sh SEE ALSO
 .Xr gethostbyname 3 ,
-.Xr named 8 ,
 .Xr resolv.conf 5 ,
 .Xr hostname 7 ,
+.Xr named 8
 .Pp
-.%T RFC1032 ,
-.%T RFC1033 ,
-.%T RFC1034 ,
-.%T RFC1035 ,
-.%T RFC974
+.%T RFC 974 ,
+.%T RFC 1032 ,
+.%T RFC 1033 ,
+.%T RFC 1034 ,
+.%T RFC 1035 ,
+.%T RFC 1535
 .Rs
 .%T "Name Server Operations Guide for BIND"
 .Re
 .Sh HISTORY
 The
 .Nm
-function appeared in 
+function appeared in
 .Bx 4.3 .