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/*
* Copyright 2009 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/*
* Copyright (C) 2009 Internet Systems Consortium, Inc. ("ISC")
*
* Permission to use, copy, modify, and/or 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 ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC 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.
*/
#include <port_before.h>
#include <arpa/nameser.h>
#include <assert.h>
#include <errno.h>
#include <string.h>
#include <port_after.h>
static int rdcpy(ns_newmsg *, ns_type, const u_char *, size_t);
/* Initialize a "newmsg" object to empty.
*/
int
ns_newmsg_init(u_char *buffer, size_t bufsiz, ns_newmsg *handle) {
ns_msg *msg = &handle->msg;
memset(handle, 0, sizeof *handle);
msg->_msg = buffer;
msg->_eom = buffer + bufsiz;
msg->_sect = ns_s_qd;
msg->_rrnum = 0;
msg->_msg_ptr = buffer + NS_HFIXEDSZ;
handle->dnptrs[0] = msg->_msg;
handle->dnptrs[1] = NULL;
handle->lastdnptr = &handle->dnptrs[sizeof handle->dnptrs /
sizeof handle->dnptrs[0] - 1];
return (0);
}
/* Initialize a "newmsg" object by copying an existing parsed message.
*/
int
ns_newmsg_copy(ns_newmsg *handle, ns_msg *msg) {
ns_flag flag;
ns_sect sect;
ns_newmsg_id(handle, ns_msg_id(*msg));
for (flag = ns_f_qr; flag < ns_f_max; flag++)
ns_newmsg_flag(handle, flag, ns_msg_getflag(*msg, flag));
for (sect = ns_s_qd; sect < ns_s_max; sect++) {
int i, count;
count = ns_msg_count(*msg, sect);
for (i = 0; i < count; i++) {
ns_rr2 rr;
int x;
if (ns_parserr2(msg, sect, i, &rr) < 0)
return (-1);
if (sect == ns_s_qd)
x = ns_newmsg_q(handle,
ns_rr_nname(rr),
ns_rr_type(rr),
ns_rr_class(rr));
else
x = ns_newmsg_rr(handle, sect,
ns_rr_nname(rr),
ns_rr_type(rr),
ns_rr_class(rr),
ns_rr_ttl(rr),
ns_rr_rdlen(rr),
ns_rr_rdata(rr));
if (x < 0)
return (-1);
}
}
return (0);
}
/* Set the message-ID in a "newmsg" object.
*/
void
ns_newmsg_id(ns_newmsg *handle, u_int16_t id) {
ns_msg *msg = &handle->msg;
msg->_id = id;
}
/* Set a flag (including rcode or opcode) in a "newmsg" object.
*/
void
ns_newmsg_flag(ns_newmsg *handle, ns_flag flag, u_int value) {
extern struct _ns_flagdata _ns_flagdata[16];
struct _ns_flagdata *fd = &_ns_flagdata[flag];
ns_msg *msg = &handle->msg;
assert(flag < ns_f_max);
msg->_flags &= (~fd->mask);
msg->_flags |= (value << fd->shift);
}
/* Add a question (or zone, if it's an update) to a "newmsg" object.
*/
int
ns_newmsg_q(ns_newmsg *handle, ns_nname_ct qname,
ns_type qtype, ns_class qclass)
{
ns_msg *msg = &handle->msg;
u_char *t;
int n;
if (msg->_sect != ns_s_qd) {
errno = ENODEV;
return (-1);
}
t = (u_char *) (unsigned long) msg->_msg_ptr;
if (msg->_rrnum == 0)
msg->_sections[ns_s_qd] = t;
n = ns_name_pack(qname, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
if (t + QFIXEDSZ >= msg->_eom) {
errno = EMSGSIZE;
return (-1);
}
NS_PUT16(qtype, t);
NS_PUT16(qclass, t);
msg->_msg_ptr = t;
msg->_counts[ns_s_qd] = ++msg->_rrnum;
return (0);
}
/* Add an RR to a "newmsg" object.
*/
int
ns_newmsg_rr(ns_newmsg *handle, ns_sect sect,
ns_nname_ct name, ns_type type,
ns_class rr_class, u_int32_t ttl,
u_int16_t rdlen, const u_char *rdata)
{
ns_msg *msg = &handle->msg;
u_char *t;
int n;
if (sect < msg->_sect) {
errno = ENODEV;
return (-1);
}
t = (u_char *) (unsigned long) msg->_msg_ptr;
if (sect > msg->_sect) {
msg->_sect = sect;
msg->_sections[sect] = t;
msg->_rrnum = 0;
}
n = ns_name_pack(name, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
if (t + RRFIXEDSZ + rdlen >= msg->_eom) {
errno = EMSGSIZE;
return (-1);
}
NS_PUT16(type, t);
NS_PUT16(rr_class, t);
NS_PUT32(ttl, t);
msg->_msg_ptr = t;
if (rdcpy(handle, type, rdata, rdlen) < 0)
return (-1);
msg->_counts[sect] = ++msg->_rrnum;
return (0);
}
/* Complete a "newmsg" object and return its size for use in write().
* (Note: the "newmsg" object is also made ready for ns_parserr() etc.)
*/
size_t
ns_newmsg_done(ns_newmsg *handle) {
ns_msg *msg = &handle->msg;
ns_sect sect;
u_char *t;
t = (u_char *) (unsigned long) msg->_msg;
NS_PUT16(msg->_id, t);
NS_PUT16(msg->_flags, t);
for (sect = 0; sect < ns_s_max; sect++)
NS_PUT16(msg->_counts[sect], t);
msg->_eom = msg->_msg_ptr;
msg->_sect = ns_s_max;
msg->_rrnum = -1;
msg->_msg_ptr = NULL;
return (msg->_eom - msg->_msg);
}
/* Private. */
/* Copy an RDATA, using compression pointers where RFC1035 permits.
*/
static int
rdcpy(ns_newmsg *handle, ns_type type, const u_char *rdata, size_t rdlen) {
ns_msg *msg = &handle->msg;
u_char *p = (u_char *) (unsigned long) msg->_msg_ptr;
u_char *t = p + NS_INT16SZ;
u_char *s = t;
int n;
switch (type) {
case ns_t_soa:
/* MNAME. */
n = ns_name_pack(rdata, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
if (ns_name_skip(&rdata, msg->_eom) < 0)
return (-1);
/* ANAME. */
n = ns_name_pack(rdata, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
if (ns_name_skip(&rdata, msg->_eom) < 0)
return (-1);
/* Serial, Refresh, Retry, Expiry, and Minimum. */
if ((msg->_eom - t) < (NS_INT32SZ * 5)) {
errno = EMSGSIZE;
return (-1);
}
memcpy(t, rdata, NS_INT32SZ * 5);
t += (NS_INT32SZ * 5);
break;
case ns_t_ptr:
case ns_t_cname:
case ns_t_ns:
/* PTRDNAME, CNAME, or NSDNAME. */
n = ns_name_pack(rdata, t, msg->_eom - t,
handle->dnptrs, handle->lastdnptr);
if (n < 0)
return (-1);
t += n;
break;
default:
memcpy(t, rdata, rdlen);
t += rdlen;
}
NS_PUT16(t - s, p);
msg->_msg_ptr = t;
return (0);
}
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