ossp-pkg/adns/adns_setup.c
/*
* setup.c
* - configuration file parsing
* - management of global state
*/
/*
* This file is
* Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
*
* It is part of adns, which is
* Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk>
* Copyright (C) 1999-2000 Tony Finch <dot@dotat.at>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <stdlib.h>
#include <errno.h>
#include <limits.h>
#include <unistd.h>
#include <fcntl.h>
#include <netdb.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "adns_internal.h"
static void readconfig(adns_state ads, const char *filename, int warnmissing);
static void addserver(adns_state ads, struct in_addr addr) {
int i;
struct server *ss;
for (i=0; i<ads->nservers; i++) {
if (ads->servers[i].addr.s_addr == addr.s_addr) {
adns__debug(ads,-1,0,"duplicate nameserver %s ignored",inet_ntoa(addr));
return;
}
}
if (ads->nservers>=MAXSERVERS) {
adns__diag(ads,-1,0,"too many nameservers, ignoring %s",inet_ntoa(addr));
return;
}
ss= ads->servers+ads->nservers;
ss->addr= addr;
ads->nservers++;
}
static void freesearchlist(adns_state ads) {
if (ads->nsearchlist) free(*ads->searchlist);
free(ads->searchlist);
}
static void saveerr(adns_state ads, int en) {
if (!ads->configerrno) ads->configerrno= en;
}
static void configparseerr(adns_state ads, const char *fn, int lno,
const char *fmt, ...) {
va_list al;
saveerr(ads,EINVAL);
if (!ads->diagfile || (ads->iflags & adns_if_noerrprint)) return;
if (lno==-1) fprintf(ads->diagfile,"adns: %s: ",fn);
else fprintf(ads->diagfile,"adns: %s:%d: ",fn,lno);
va_start(al,fmt);
vfprintf(ads->diagfile,fmt,al);
va_end(al);
fputc('\n',ads->diagfile);
}
static int nextword(const char **bufp_io, const char **word_r, int *l_r) {
const char *p, *q;
p= *bufp_io;
while (ctype_whitespace(*p)) p++;
if (!*p) return 0;
q= p;
while (*q && !ctype_whitespace(*q)) q++;
*l_r= q-p;
*word_r= p;
*bufp_io= q;
return 1;
}
static void ccf_nameserver(adns_state ads, const char *fn, int lno, const char *buf) {
struct in_addr ia;
if (!inet_aton(buf,&ia)) {
configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
return;
}
adns__debug(ads,-1,0,"using nameserver %s",inet_ntoa(ia));
addserver(ads,ia);
}
static void ccf_search(adns_state ads, const char *fn, int lno, const char *buf) {
const char *bufp, *word;
char *newchars, **newptrs, **pp;
int count, tl, l;
if (!buf) return;
bufp= buf;
count= 0;
tl= 0;
while (nextword(&bufp,&word,&l)) { count++; tl += l+1; }
newptrs= malloc(sizeof(char*)*count); if (!newptrs) { saveerr(ads,errno); return; }
newchars= malloc(tl); if (!newchars) { saveerr(ads,errno); free(newptrs); return; }
bufp= buf;
pp= newptrs;
while (nextword(&bufp,&word,&l)) {
*pp++= newchars;
memcpy(newchars,word,l);
newchars += l;
*newchars++ = 0;
}
freesearchlist(ads);
ads->nsearchlist= count;
ads->searchlist= newptrs;
}
static void ccf_sortlist(adns_state ads, const char *fn, int lno, const char *buf) {
const char *word;
char tbuf[200], *slash, *ep;
struct in_addr base, mask;
int l;
unsigned long initial, baselocal;
if (!buf) return;
ads->nsortlist= 0;
while (nextword(&buf,&word,&l)) {
if (ads->nsortlist >= MAXSORTLIST) {
adns__diag(ads,-1,0,"too many sortlist entries, ignoring %.*s onwards",l,word);
return;
}
if (l >= sizeof(tbuf)) {
configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,word);
continue;
}
memcpy(tbuf,word,l); tbuf[l]= 0;
slash= strchr(tbuf,'/');
if (slash) *slash++= 0;
if (!inet_aton(tbuf,&base)) {
configparseerr(ads,fn,lno,"invalid address `%s' in sortlist",tbuf);
continue;
}
if (slash) {
if (strchr(slash,'.')) {
if (!inet_aton(slash,&mask)) {
configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash);
continue;
}
if (base.s_addr & ~mask.s_addr) {
configparseerr(ads,fn,lno,
"mask `%s' in sortlist overlaps address `%s'",slash,tbuf);
continue;
}
} else {
initial= strtoul(slash,&ep,10);
if (*ep || initial>32) {
configparseerr(ads,fn,lno,"mask length `%s' invalid",slash);
continue;
}
mask.s_addr= htonl((0x0ffffffffUL) << (32-initial));
}
} else {
baselocal= ntohl(base.s_addr);
if (!baselocal & 0x080000000UL) /* class A */
mask.s_addr= htonl(0x0ff000000UL);
else if ((baselocal & 0x0c0000000UL) == 0x080000000UL)
mask.s_addr= htonl(0x0ffff0000UL); /* class B */
else if ((baselocal & 0x0f0000000UL) == 0x0e0000000UL)
mask.s_addr= htonl(0x0ff000000UL); /* class C */
else {
configparseerr(ads,fn,lno,
"network address `%s' in sortlist is not in classed ranges,"
" must specify mask explicitly", tbuf);
continue;
}
}
ads->sortlist[ads->nsortlist].base= base;
ads->sortlist[ads->nsortlist].mask= mask;
ads->nsortlist++;
}
}
static void ccf_options(adns_state ads, const char *fn, int lno, const char *buf) {
const char *word;
char *ep;
unsigned long v;
int l;
if (!buf) return;
while (nextword(&buf,&word,&l)) {
if (l==5 && !memcmp(word,"debug",5)) {
ads->iflags |= adns_if_debug;
continue;
}
if (l>=6 && !memcmp(word,"ndots:",6)) {
v= strtoul(word+6,&ep,10);
if (l==6 || ep != word+l || v > INT_MAX) {
configparseerr(ads,fn,lno,"option `%.*s' malformed or has bad value",l,word);
continue;
}
ads->searchndots= v;
continue;
}
if (l>=12 && !memcmp(word,"adns_checkc:",12)) {
if (!strcmp(word+12,"none")) {
ads->iflags &= ~adns_if_checkc_freq;
ads->iflags |= adns_if_checkc_entex;
} else if (!strcmp(word+12,"entex")) {
ads->iflags &= ~adns_if_checkc_freq;
ads->iflags |= adns_if_checkc_entex;
} else if (!strcmp(word+12,"freq")) {
ads->iflags |= adns_if_checkc_freq;
} else {
configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
"(must be none, entex or freq", word+12);
}
continue;
}
adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,word);
}
}
static void ccf_clearnss(adns_state ads, const char *fn, int lno, const char *buf) {
ads->nservers= 0;
}
static void ccf_include(adns_state ads, const char *fn, int lno, const char *buf) {
if (!*buf) {
configparseerr(ads,fn,lno,"`include' directive with no filename");
return;
}
readconfig(ads,buf,1);
}
static const struct configcommandinfo {
const char *name;
void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
} configcommandinfos[]= {
{ "nameserver", ccf_nameserver },
{ "domain", ccf_search },
{ "search", ccf_search },
{ "sortlist", ccf_sortlist },
{ "options", ccf_options },
{ "clearnameservers", ccf_clearnss },
{ "include", ccf_include },
{ 0 }
};
typedef union {
FILE *file;
const char *text;
} getline_ctx;
static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename,
int lno, char *buf, int buflen) {
FILE *file= src_io->file;
int c, i;
char *p;
p= buf;
buflen--;
i= 0;
for (;;) { /* loop over chars */
if (i == buflen) {
adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
goto x_badline;
}
c= getc(file);
if (!c) {
adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
goto x_badline;
} else if (c == '\n') {
break;
} else if (c == EOF) {
if (ferror(file)) {
saveerr(ads,errno);
adns__diag(ads,-1,0,"%s:%d: read error: %s",filename,lno,strerror(errno));
return -1;
}
if (!i) return -1;
break;
} else {
*p++= c;
i++;
}
}
*p++= 0;
return i;
x_badline:
saveerr(ads,EINVAL);
while ((c= getc(file)) != EOF && c != '\n');
return -2;
}
static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename,
int lno, char *buf, int buflen) {
const char *cp= src_io->text;
int l;
if (!cp || !*cp) return -1;
if (*cp == ';' || *cp == '\n') cp++;
l= strcspn(cp,";\n");
src_io->text = cp+l;
if (l >= buflen) {
adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
saveerr(ads,EINVAL);
return -2;
}
memcpy(buf,cp,l);
buf[l]= 0;
return l;
}
static void readconfiggeneric(adns_state ads, const char *filename,
int (*getline)(adns_state ads, getline_ctx*,
const char *filename, int lno,
char *buf, int buflen),
/* Returns >=0 for success, -1 for EOF or error
* (error will have been reported), or -2 for
* bad line was encountered, try again.
*/
getline_ctx gl_ctx) {
char linebuf[2000], *p, *q;
int lno, l, dirl;
const struct configcommandinfo *ccip;
for (lno=1;
(l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
lno++) {
if (l == -2) continue;
while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
linebuf[l]= 0;
p= linebuf;
while (ctype_whitespace(*p)) p++;
if (*p == '#' || !*p) continue;
q= p;
while (*q && !ctype_whitespace(*q)) q++;
dirl= q-p;
for (ccip=configcommandinfos;
ccip->name && !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
ccip++);
if (!ccip->name) {
adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
filename,lno,q-p,p);
continue;
}
while (ctype_whitespace(*q)) q++;
ccip->fn(ads,filename,lno,q);
}
}
static const char *instrum_getenv(adns_state ads, const char *envvar) {
const char *value;
value= getenv(envvar);
if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar);
else adns__debug(ads,-1,0,"environment variable %s set to `%s'",envvar,value);
return value;
}
static void readconfig(adns_state ads, const char *filename, int warnmissing) {
getline_ctx gl_ctx;
gl_ctx.file= fopen(filename,"r");
if (!gl_ctx.file) {
if (errno == ENOENT) {
if (warnmissing)
adns__debug(ads,-1,0,"configuration file `%s' does not exist",filename);
return;
}
saveerr(ads,errno);
adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
filename,strerror(errno));
return;
}
readconfiggeneric(ads,filename,gl_file,gl_ctx);
fclose(gl_ctx.file);
}
static void readconfigtext(adns_state ads, const char *text, const char *showname) {
getline_ctx gl_ctx;
gl_ctx.text= text;
readconfiggeneric(ads,showname,gl_text,gl_ctx);
}
static void readconfigenv(adns_state ads, const char *envvar) {
const char *filename;
if (ads->iflags & adns_if_noenv) {
adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
return;
}
filename= instrum_getenv(ads,envvar);
if (filename) readconfig(ads,filename,1);
}
static void readconfigenvtext(adns_state ads, const char *envvar) {
const char *textdata;
if (ads->iflags & adns_if_noenv) {
adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
return;
}
textdata= instrum_getenv(ads,envvar);
if (textdata) readconfigtext(ads,textdata,envvar);
}
int adns__setnonblock(adns_state ads, int fd) {
int r;
r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
r |= O_NONBLOCK;
r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
return 0;
}
static int init_begin(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
adns_state ads;
ads= malloc(sizeof(*ads)); if (!ads) return errno;
ads->iflags= flags;
ads->diagfile= diagfile;
ads->configerrno= 0;
ADNS_LIST_INIT(ads->udpw);
ADNS_LIST_INIT(ads->tcpw);
ADNS_LIST_INIT(ads->childw);
ADNS_LIST_INIT(ads->output);
ads->forallnext= 0;
ads->nextid= 0x311f;
ads->udpsocket= ads->tcpsocket= -1;
adns__vbuf_init(&ads->tcpsend);
adns__vbuf_init(&ads->tcprecv);
ads->tcprecv_skip= 0;
ads->nservers= ads->nsortlist= ads->nsearchlist= ads->tcpserver= 0;
ads->searchndots= 1;
ads->tcpstate= server_disconnected;
timerclear(&ads->tcptimeout);
ads->searchlist= 0;
*ads_r= ads;
return 0;
}
static int init_finish(adns_state ads) {
struct in_addr ia;
struct protoent *proto;
int r;
if (!ads->nservers) {
if (ads->diagfile && ads->iflags & adns_if_debug)
fprintf(ads->diagfile,"adns: no nameservers, using localhost\n");
ia.s_addr= htonl(INADDR_LOOPBACK);
addserver(ads,ia);
}
proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
ads->udpsocket= socket(AF_INET,SOCK_DGRAM,proto->p_proto);
if (ads->udpsocket<0) { r= errno; goto x_free; }
r= adns__setnonblock(ads,ads->udpsocket);
if (r) { r= errno; goto x_closeudp; }
return 0;
x_closeudp:
close(ads->udpsocket);
x_free:
free(ads);
return r;
}
static void init_abort(adns_state ads) {
if (ads->nsearchlist) {
free(ads->searchlist[0]);
free(ads->searchlist);
}
free(ads);
}
int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
adns_state ads;
const char *res_options, *adns_res_options;
int r;
r= init_begin(&ads, flags, diagfile ? diagfile : stderr);
if (r) return r;
res_options= instrum_getenv(ads,"RES_OPTIONS");
adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
ccf_options(ads,"RES_OPTIONS",-1,res_options);
ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
readconfig(ads,"/etc/resolv.conf",1);
readconfig(ads,"/etc/resolv-adns.conf",0);
readconfigenv(ads,"RES_CONF");
readconfigenv(ads,"ADNS_RES_CONF");
readconfigenvtext(ads,"RES_CONF_TEXT");
readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
ccf_options(ads,"RES_OPTIONS",-1,res_options);
ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
if (ads->configerrno && ads->configerrno != EINVAL) {
r= ads->configerrno;
init_abort(ads);
return r;
}
r= init_finish(ads);
if (r) return r;
adns__consistency(ads,0,cc_entex);
*ads_r= ads;
return 0;
}
int adns_init_strcfg(adns_state *ads_r, adns_initflags flags,
FILE *diagfile, const char *configtext) {
adns_state ads;
int r;
r= init_begin(&ads, flags, diagfile); if (r) return r;
readconfigtext(ads,configtext,"<supplied configuration text>");
if (ads->configerrno) {
r= ads->configerrno;
init_abort(ads);
return r;
}
r= init_finish(ads); if (r) return r;
adns__consistency(ads,0,cc_entex);
*ads_r= ads;
return 0;
}
void adns_finish(adns_state ads) {
adns__consistency(ads,0,cc_entex);
for (;;) {
if (ads->udpw.head) adns_cancel(ads->udpw.head);
else if (ads->tcpw.head) adns_cancel(ads->tcpw.head);
else if (ads->childw.head) adns_cancel(ads->childw.head);
else if (ads->output.head) adns_cancel(ads->output.head);
else break;
}
close(ads->udpsocket);
if (ads->tcpsocket >= 0) close(ads->tcpsocket);
adns__vbuf_free(&ads->tcpsend);
adns__vbuf_free(&ads->tcprecv);
freesearchlist(ads);
free(ads);
}
void adns_forallqueries_begin(adns_state ads) {
adns__consistency(ads,0,cc_entex);
ads->forallnext=
ads->udpw.head ? ads->udpw.head :
ads->tcpw.head ? ads->tcpw.head :
ads->childw.head ? ads->childw.head :
ads->output.head;
}
adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
adns_query qu, nqu;
adns__consistency(ads,0,cc_entex);
nqu= ads->forallnext;
for (;;) {
qu= nqu;
if (!qu) return 0;
if (qu->next) {
nqu= qu->next;
} else if (qu == ads->udpw.tail) {
nqu=
ads->tcpw.head ? ads->tcpw.head :
ads->childw.head ? ads->childw.head :
ads->output.head;
} else if (qu == ads->tcpw.tail) {
nqu=
ads->childw.head ? ads->childw.head :
ads->output.head;
} else if (qu == ads->childw.tail) {
nqu= ads->output.head;
} else {
nqu= 0;
}
if (!qu->parent) break;
}
ads->forallnext= nqu;
if (context_r) *context_r= qu->ctx.ext;
return qu;
}
