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Diffstat (limited to 'lib/libc/net/getrrsetbyname.3')
-rw-r--r-- | lib/libc/net/getrrsetbyname.3 | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/lib/libc/net/getrrsetbyname.3 b/lib/libc/net/getrrsetbyname.3 new file mode 100644 index 00000000000..3b8c06999ec --- /dev/null +++ b/lib/libc/net/getrrsetbyname.3 @@ -0,0 +1,149 @@ +.\" $Id: getrrsetbyname.3,v 1.1 2001/08/06 14:40:47 jakob Exp $ +.\" +.\" Copyright (C) 2000, 2001 Internet Software Consortium. +.\" +.\" Permission to use, copy, modify, and distribute this software for any +.\" purpose with or without fee is hereby granted, provided that the above +.\" copyright notice and this permission notice appear in all copies. +.\" +.\" THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM +.\" DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL +.\" INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, +.\" INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING +.\" FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, +.\" NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION +.\" WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +.\" +.Dd Oct 18, 2000 +.Dt GETRRSETBYNAME 3 +.Os +.Sh NAME +.Nm getrrsetbyname +.Nd retrieve DNS records +.Sh SYNOPSIS +.Fd #include <netdb.h> +.Ft int +.Fn getrrsetbyname "const char *hostname" "unsigned int rdclass" \ +"unsigned int rdtype" "unsigned int flags" "struct rrsetinfo **res" +.Ft int +.Fn freerrset "struct rrsetinfo **rrset" +.Sh DESCRIPTION +.Fn getrrsetbyname +gets a set of resource records associated with a +.Fa hostname , +.Fa class +and +.Fa type . +.Fa hostname +is a pointer a to null-terminated string. +The +.Fa flags +field is currently unused and must be zero. +.Pp +After a successful call to +.Fn getrrsetbyname , +.Fa *res +is a pointer to an +.Li rrsetinfo +structure, containing a list of one or more +.Li rdatainfo +structures containing resource records and potentially another list of +.Li rdatainfo +structures containing SIG resource records associated with those records. +The members +.Li rri_rdclass +and +.Li rri_rdtype +are copied from the parameters. +.Li rri_ttl +and +.Li rri_name +are properties of the obtained rrset. +The resource records contained in +.Li rri_rdatas +and +.Li rri_sigs +are in uncompressed DNS wire format. +Properties of the rdataset are represented in the +.Li rri_flags +bitfield. If the +.Dv RRSET_VALIDATED +bit is set, the data has been DNSSEC +validated and the signatures verified. +.Pp +The following structures are used: +.Bd -literal -offset +struct rdatainfo { + unsigned int rdi_length; /* length of data */ + unsigned char *rdi_data; /* record data */ +}; + +struct rrsetinfo { + unsigned int rri_flags; /* RRSET_VALIDATED ... */ + unsigned int rri_rdclass; /* class number */ + unsigned int rri_rdtype; /* RR type number */ + unsigned int rri_ttl; /* time to live */ + unsigned int rri_nrdatas; /* size of rdatas array */ + unsigned int rri_nsigs; /* size of sigs array */ + char *rri_name; /* canonical name */ + struct rdatainfo *rri_rdatas; /* individual records */ + struct rdatainfo *rri_sigs; /* individual signatures */ +}; +.Ed +.Pp +All of the information returned by +.Fn getrrsetbyname +is dynamically allocated: the +.Li rrsetinfo +and +.Li rdatainfo +structures, +and the canonical host name strings pointed to by the +.Li rrsetinfostructure. +Memory allocated for the dynamically allocated structures created by +a successful call to +.Fn getrrsetbyname +is released by +.Fn freerrset . +.Li rrset +is a pointer to a +.Li struct rrset +created by a call to +.Fn getrrsetbyname . +.Pp +If the EDNS0 option is activated in +.Xr resolv.conf 3 , +.Fn getrrsetbyname +will request DNSSEC authentication using the EDNS0 DNSSEC OK (DO) bit. +.Sh "RETURN VALUES" +.Fn getrrsetbyname +returns zero on success, and one of the following error +codes if an error occurred: +.Pp +.Bl -tag -width ERRSET_NOMEMORY -compact +.It Dv ERRSET_NONAME +the name does not exist +.It Dv ERRSET_NODATA +the name exists, but does not have data of the desired type +.It Dv ERRSET_NOMEMORY +memory could not be allocated +.It Dv ERRSET_INVAL +a parameter is invalid +.It Dv ERRSET_FAIL +other failure +.El +.Sh SEE ALSO +.Xr resolver 3 , +.Xr resolv.conf 5 , +.Xr named 8 +.Sh HISTORY +.Nm +first appeared in +.Ox 3.0 . +.Sh BUGS +The data in +.Li *rdi_data +should be returned in uncompressed wire format. +Currently, the data is in compressed format and the caller can't +uncompress since it doesn't have the full message. |