/*
* dbcreate.c -- routines to create an nsd(8) name database
*
* Copyright (c) 2001-2006, NLnet Labs. All rights reserved.
*
* See LICENSE for the license.
*
*/
/* pathname directory separator character */
#define PATHSEP '/'
/** add an rdata (uncompressed) to the destination */
static size_t
add_rdata(rr_type* rr, unsigned i, uint8_t* buf, size_t buflen)
{
switch(rdata_atom_wireformat_type(rr->type, i)) {
case RDATA_WF_COMPRESSED_DNAME:
case RDATA_WF_UNCOMPRESSED_DNAME:
{
const dname_type* dname = domain_dname(
rdata_atom_domain(rr->rdatas[i]));
if(dname->name_size > buflen)
return 0;
memmove(buf, dname_name(dname), dname->name_size);
return dname->name_size;
}
default:
break;
}
if(rdata_atom_size(rr->rdatas[i]) > buflen)
return 0;
memmove(buf, rdata_atom_data(rr->rdatas[i]),
rdata_atom_size(rr->rdatas[i]));
return rdata_atom_size(rr->rdatas[i]);
}
/* marshal rdata into buffer, must be MAX_RDLENGTH in size */
size_t
rr_marshal_rdata(rr_type* rr, uint8_t* rdata, size_t sz)
{
size_t len = 0;
unsigned i;
assert(rr);
for(i=0; i<rr->rdata_count; i++) {
len += add_rdata(rr, i, rdata+len, sz-len);
}
return len;
}
int
print_rrs(FILE* out, struct zone* zone)
{
rrset_type *rrset;
domain_type *domain = zone->apex;
region_type* region = region_create(xalloc, free);
region_type* rr_region = region_create(xalloc, free);
buffer_type* rr_buffer = buffer_create(region, MAX_RDLENGTH);
struct state_pretty_rr* state = create_pretty_rr(region);
/* first print the SOA record for the zone */
if(zone->soa_rrset) {
size_t i;
for(i=0; i < zone->soa_rrset->rr_count; i++) {
if(!print_rr(out, state, &zone->soa_rrset->rrs[i],
rr_region, rr_buffer)){
log_msg(LOG_ERR, "There was an error "
"printing SOARR to zone %s",
zone->opts->name);
region_destroy(region);
region_destroy(rr_region);
return 0;
}
}
}
/* go through entire tree below the zone apex (incl subzones) */
while(domain && domain_is_subdomain(domain, zone->apex))
{
for(rrset = domain->rrsets; rrset; rrset=rrset->next)
{
size_t i;
if(rrset->zone != zone || rrset == zone->soa_rrset)
continue;
for(i=0; i < rrset->rr_count; i++) {
if(!print_rr(out, state, &rrset->rrs[i],
rr_region, rr_buffer)){
log_msg(LOG_ERR, "There was an error "
"printing RR to zone %s",
zone->opts->name);
region_destroy(region);
region_destroy(rr_region);
return 0;
}
}
}
domain = domain_next(domain);
}
region_destroy(region);
region_destroy(rr_region);
return 1;
}
static int
print_header(zone_type* zone, FILE* out, time_t* now, const char* logs)
{
char buf[4096+16];
/* ctime prints newline at end of this line */
snprintf(buf, sizeof(buf), "; zone %s written by NSD %s on %s",
zone->opts->name, PACKAGE_VERSION, ctime(now));
if(!write_data(out, buf, strlen(buf)))
return 0;
if(!logs || logs[0] == 0) return 1;
snprintf(buf, sizeof(buf), "; %s\n", logs);
return write_data(out, buf, strlen(buf));
}
static int
write_to_zonefile(zone_type* zone, const char* filename, const char* logs)
{
time_t now = time(0);
FILE *out = fopen(filename, "w");
if(!out) {
log_msg(LOG_ERR, "cannot write zone %s file %s: %s",
zone->opts->name, filename, strerror(errno));
return 0;
}
if(!print_header(zone, out, &now, logs)) {
fclose(out);
log_msg(LOG_ERR, "There was an error printing "
"the header to zone %s", zone->opts->name);
return 0;
}
if(!print_rrs(out, zone)) {
fclose(out);
return 0;
}
if(fclose(out) != 0) {
log_msg(LOG_ERR, "cannot write zone %s to file %s: fclose: %s",
zone->opts->name, filename, strerror(errno));
return 0;
}
return 1;
}
/** create directories above this file, .../dir/dir/dir/file */
int
create_dirs(const char* path)
{
char dir[4096];
char* p;
strlcpy(dir, path, sizeof(dir));
/* if we start with / then do not try to create '' */
if(dir[0] == PATHSEP)
p = strchr(dir+1, PATHSEP);
else p = strchr(dir, PATHSEP);
/* create each directory component from the left */
while(p) {
assert(*p == PATHSEP);
*p = 0; /* end the directory name here */
if(mkdir(dir
#ifndef MKDIR_HAS_ONE_ARG
, 0750
#endif
) == -1) {
if(errno != EEXIST) {
log_msg(LOG_ERR, "create dir %s: %s",
dir, strerror(errno));
*p = PATHSEP; /* restore input string */
return 0;
}
/* it already exists, OK, continue */
}
*p = PATHSEP;
p = strchr(p+1, PATHSEP);
}
return 1;
}
/** create pathname components and check if file exists */
static int
create_path_components(const char* path, int* notexist)
{
/* stat the file, to see if it exists, and if its directories exist */
struct stat s;
if(stat(path, &s) != 0) {
if(errno == ENOENT) {
*notexist = 1;
/* see if we need to create pathname components */
return create_dirs(path);
}
log_msg(LOG_ERR, "cannot stat %s: %s", path, strerror(errno));
return 0;
}
*notexist = 0;
return 1;
}
void
namedb_write_zonefile(struct nsd* nsd, struct zone_options* zopt)
{
const char* zfile;
int notexist = 0;
zone_type* zone;
/* if no zone exists, it has no contents or it has no zonefile
* configured, then no need to write data to disk */
if(!zopt->pattern->zonefile)
return;
zone = namedb_find_zone(nsd->db, (const dname_type*)zopt->node.key);
if(!zone || !zone->apex || !zone->soa_rrset)
return;
/* write if file does not exist, or if changed */
/* so, determine filename, create directory components, check exist*/
zfile = config_make_zonefile(zopt, nsd);
if(!create_path_components(zfile, ¬exist)) {
log_msg(LOG_ERR, "could not write zone %s to file %s because "
"the path could not be created", zopt->name, zfile);
return;
}
/* if not changed, do not write. */
if(notexist || zone->is_changed) {
char logs[4096];
char bakfile[4096];
struct timespec mtime;
/* write to zfile~ first, then rename if that works */
snprintf(bakfile, sizeof(bakfile), "%s~", zfile);
if(zone->logstr)
strlcpy(logs, zone->logstr, sizeof(logs));
else
logs[0] = 0;
VERBOSITY(1, (LOG_INFO, "writing zone %s to file %s",
zone->opts->name, zfile));
if(!write_to_zonefile(zone, bakfile, logs)) {
(void)unlink(bakfile); /* delete failed file */
return; /* error already printed */
}
if(rename(bakfile, zfile) == -1) {
log_msg(LOG_ERR, "rename(%s to %s) failed: %s",
bakfile, zfile, strerror(errno));
(void)unlink(bakfile); /* delete failed file */
return;
}
zone->is_changed = 0;
/* fetch the mtime of the just created zonefile so we
* do not waste effort reading it back in */
if(!file_get_mtime(zfile, &mtime, ¬exist)) {
get_time(&mtime);
}
zone->mtime = mtime;
if(zone->filename)
region_recycle(nsd->db->region, zone->filename,
strlen(zone->filename)+1);
zone->filename = region_strdup(nsd->db->region, zfile);
if(zone->logstr)
region_recycle(nsd->db->region, zone->logstr,
strlen(zone->logstr)+1);
zone->logstr = NULL;
if(zone_is_ixfr_enabled(zone) && zone->ixfr)
ixfr_write_to_file(zone, zfile);
}
}
