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/*
** Copyright 1998 - 2001 Double Precision, Inc.
** See COPYING for distribution information.
*/
#include "config.h"
#include <stdio.h>
#include "soxwrap/soxwrap.h"
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#if TIME_WITH_SYS_TIME
#include <sys/time.h>
#include <time.h>
#else
#if HAVE_SYS_TIME_H
#include <sys/time.h>
#else
#include <time.h>
#endif
#endif
#include <arpa/inet.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include "rfc1035_res.h"
#include "rfc1035.h"
#if RFC1035_IPV6
#else
struct in_addr rfc1035_addr_any={INADDR_ANY};
#endif
void rfc1035_init_timeout(struct rfc1035_res *res, unsigned s, unsigned n)
{
res->rfc1035_timeout_initial=s;
res->rfc1035_timeout_backoff=n;
}
void rfc1035_init_ns(struct rfc1035_res *res, const RFC1035_ADDR *a, unsigned n)
{
unsigned i;
unsigned j;
j=0;
random128_binary(&res->randseed);
md5_digest(&res->randseed, sizeof(res->randseed), res->randbuf);
res->randptr=0;
for (i=0; i == 0 || (i<n && i<MAXNS); i++)
{
#if RFC1035_IPV6
struct in6_addr sin;
if (n == 0)
sin=in6addr_loopback;
else
sin=a[(j+i)%n];
#else
struct in_addr sin;
if (n == 0)
{
rfc1035_aton("127.0.0.1", &sin);
}
else
sin=a[(j+i)%n];
memset(&res->nameservers[i], 0, sizeof(res->nameservers[i]));
res->nameservers[i]=sin;
#endif
res->nameservers[i]=sin;
}
res->rfc1035_nnameservers=i;
}
int rfc1035_init_defaultdomain(struct rfc1035_res *res, const char *p)
{
char *q;
if (res->rfc1035_defaultdomain)
free(res->rfc1035_defaultdomain);
if ((res->rfc1035_defaultdomain=malloc(strlen(p)+1)) == 0)
return (-1);
strcpy(res->rfc1035_defaultdomain, p);
for (q=res->rfc1035_defaultdomain; *q; q++)
if (isspace((int)(unsigned char)*q))
{
*q=0;
break;
}
return (0);
}
int rfc1035_init_resolv(struct rfc1035_res *res)
{
FILE *fp=fopen("/etc/resolv.conf", "r");
char rfc1035_buf[512];
RFC1035_ADDR ns[MAXNS];
int nns=0;
if (!fp) return (-1);
while (fgets(rfc1035_buf, sizeof(rfc1035_buf), fp))
{
char *p;
for (p=rfc1035_buf; *p; p++)
*p=tolower(*p);
for (p=rfc1035_buf; *p; p++)
if (isspace((int)(unsigned char)*p)) break;
if (*p) *p++=0;
if (strcmp(rfc1035_buf, "domain") == 0)
{
while (p && isspace((int)(unsigned char)*p))
++p;
rfc1035_init_defaultdomain(res, p);
continue;
}
if (strcmp(rfc1035_buf, "nameserver")) continue;
while (*p && isspace((int)(unsigned char)*p)) p++;
if (nns < MAXNS)
{
char *q;
for (q=p; *q && !isspace((int)(unsigned char)*q); q++)
;
*q=0;
if (rfc1035_aton(p, &ns[nns++]) < 0)
--nns;
}
}
fclose(fp);
rfc1035_init_ns(res, ns, nns);
return (0);
}
/************/
struct compresslist {
struct compresslist *next;
unsigned offset;
const char *ptr;
} ;
static int mkpacketq(void (*)(const char *, unsigned, void *), void *,
unsigned *,
const struct rfc1035_query *,
unsigned,
const char *,
struct compresslist *,
struct rfc1035_res *);
unsigned rfc1035_next_randid(struct rfc1035_res *res)
{
unsigned i;
if (res->randptr >= sizeof(res->randbuf))
{
for (i=0; i<sizeof(res->randseed); i++)
if ( ++((unsigned char *)res->randseed)[i])
break;
md5_digest(res->randseed, sizeof(res->randseed),
res->randbuf);
res->randptr=0;
}
i= ((unsigned)((unsigned char *)res->randbuf)[res->randptr] << 8) |
((unsigned char *)res->randbuf)[res->randptr+1];
res->randptr += 2;
return i;
}
int rfc1035_mkquery(struct rfc1035_res *res, /* resolver */
unsigned opcode, /* opcode */
int options, /* various options */
const struct rfc1035_query *questions,
unsigned nquestions,
void (*func)(const char *, unsigned, void *), void *arg)
{
struct {
unsigned char idhi, idlo;
unsigned char infohi, infolo;
unsigned char qhi, qlo;
unsigned char ahi, alo;
unsigned char nhi, nlo;
unsigned char auhi, aulo;
} header;
unsigned cnt;
unsigned id=rfc1035_next_randid(res);
header.idhi= id >> 8;
header.idlo= id;
header.infohi= (opcode << 3) & 0x78;
if (options & RFC1035_RESOLVE_RECURSIVE)
header.infohi |= 1;
header.infolo=0;
header.qhi=nquestions >> 8;
header.qlo=nquestions;
header.ahi=0;
header.alo=0;
header.nhi=0;
header.nlo=0;
header.auhi=0;
header.aulo=0;
(*func)( (const char *)&header, sizeof(header), arg);
cnt=sizeof(header);
if (nquestions)
if (mkpacketq(func, arg, &cnt, questions, nquestions,
questions->name, 0, res)) return (-1);
return (0);
}
int rfc1035_hostnamecmp(const char *p, const char *q)
{
while (*p || *q)
{
if (*p == '.' || *q == '.' )
{
if ( (*p && *p != '.') || (*q && *q != '.'))
return (1);
while (*p == '.') ++p;
while (*q == '.') ++q;
continue;
}
if (!*p || !*q) return (1);
if ( toupper((int)(unsigned char)*p) !=
toupper((int)(unsigned char)*q)) return (1);
++p;
++q;
}
return (0);
}
static struct compresslist *search(struct compresslist *cp, const char *name)
{
for ( ; cp; cp=cp->next)
{
if (rfc1035_hostnamecmp(name, cp->ptr) == 0 &&
(cp->offset & 0x3FFF) == cp->offset)
return (cp);
/* Packet compression uses the two high bits */
}
return (0);
}
static int mkpacketq_full(void (*)(const char *, unsigned, void *),
void *,
unsigned *,
const struct rfc1035_query *,
unsigned,
const char *,
struct compresslist *, struct rfc1035_res *);
static int mkpacketq(void (*func)(const char *, unsigned, void *), void *arg,
unsigned *cnt,
const struct rfc1035_query *qp,
unsigned nqp,
const char *nameptr,
struct compresslist *comp_list,
struct rfc1035_res *res)
{
char *buf;
int rc;
if (!res->rfc1035_defaultdomain || strchr(nameptr, '.'))
return (mkpacketq_full(func, arg, cnt, qp, nqp, nameptr,
comp_list, res));
/* Append default domain */
if ((buf=malloc(strlen(nameptr)+
strlen(res->rfc1035_defaultdomain)+2)) == 0)
return (-1);
strcat(strcat(strcpy(buf, nameptr), "."),
res->rfc1035_defaultdomain);
rc=mkpacketq_full(func, arg, cnt, qp, nqp, buf, comp_list, res);
free(buf);
return (rc);
}
static int mkpacketq_full(void (*func)(const char *, unsigned, void *),
void *arg,
unsigned *cnt,
const struct rfc1035_query *qp,
unsigned nqp,
const char *nameptr,
struct compresslist *comp_list,
struct rfc1035_res *res)
{
unsigned llen;
struct compresslist *cp;
while (nameptr && *nameptr == '.')
++nameptr;
if (!nameptr || !*nameptr)
{
struct {
unsigned char padtail;
unsigned char qtypehi, qtypelo;
unsigned char qclasshi, qclasslo;
} qtail;
qtail.padtail=0;
qtail.qtypehi=qp->qtype >> 8;
qtail.qtypelo=qp->qtype;
qtail.qclasshi=qp->qclass >> 8;
qtail.qclasslo=qp->qclass;
(*func)((const char *)&qtail, sizeof(qtail), arg);
++qp;
--nqp;
*cnt += sizeof(qtail);
if (nqp)
return (mkpacketq(func, arg, cnt,
qp, nqp, qp->name, comp_list, res));
return (0);
}
for (llen=0; nameptr[llen] && nameptr[llen] != '.'; llen++)
;
cp=search(comp_list, nameptr);
if (cp)
{
struct {
unsigned char ptrhi, ptrlo;
unsigned char qtypehi, qtypelo;
unsigned char qclasshi, qclasslo;
} qtail;
qtail.ptrhi= (cp->offset >> 8) | 0xC0;
qtail.ptrlo= cp->offset;
qtail.qtypehi=qp->qtype >> 8;
qtail.qtypelo=qp->qtype;
qtail.qclasshi=qp->qclass >> 8;
qtail.qclasslo=qp->qclass;
(*func)( (const char *)&qtail, sizeof(qtail), arg);
++qp;
--nqp;
*cnt += sizeof(qtail);
if (nqp)
return (mkpacketq(func, arg, cnt,
qp, nqp, qp->name, comp_list, res));
}
else
{
unsigned n=llen;
unsigned char c;
struct compresslist newc;
if (n > 63) return (-1);
newc.next=comp_list;
newc.offset= *cnt;
newc.ptr=nameptr;
c=(unsigned char)n;
(*func)((const char *) &c, 1, arg);
(*func)( nameptr, c, arg);
*cnt += 1+c;
return (mkpacketq_full(func, arg, cnt,
qp, nqp, nameptr+llen, &newc, res));
}
return (0);
}
/*******************************************************/
unsigned rfc1035_init_nscount(struct rfc1035_res *res)
{
if (res->rfc1035_nnameservers <= 0)
rfc1035_init_resolv(res);
return (res->rfc1035_nnameservers);
}
const RFC1035_ADDR *rfc1035_init_nsget(struct rfc1035_res *res)
{
if (res->rfc1035_nnameservers <= 0)
rfc1035_init_resolv(res);
return (res->nameservers);
}
int rfc1035_wait_reply(int fd, unsigned nsecs)
{
fd_set fds;
struct timeval tv;
int n;
FD_ZERO(&fds);
FD_SET(fd, &fds);
tv.tv_sec=nsecs;
tv.tv_usec=0;
while ((n=sox_select(fd+1, &fds, 0, 0, &tv)) < 0)
{
if (errno != EINTR)
break;
}
if (n > 0 && FD_ISSET(fd, &fds))
return (0);
errno=ETIMEDOUT;
return (-1);
}
int rfc1035_wait_query(int fd, unsigned nsecs)
{
fd_set fds;
struct timeval tv;
int n;
FD_ZERO(&fds);
FD_SET(fd, &fds);
tv.tv_sec=nsecs;
tv.tv_usec=0;
while ((n=sox_select(fd+1, 0, &fds, 0, &tv)) < 0)
{
if (errno != EINTR)
break;
}
if (n > 0 && FD_ISSET(fd, &fds))
return (0);
errno=ETIMEDOUT;
return (-1);
}
