#include "busybox.h"
-static char *fileconf = "/etc/dnsd.conf";
+static const char *fileconf = "/etc/dnsd.conf";
#define LOCK_FILE "/var/run/dnsd.lock"
-#define LOG_FILE "/var/log/dnsd.log"
-// Must matct getopt32 call
+// Must match getopt32 call
#define OPT_daemon (option_mask32 & 0x10)
#define OPT_verbose (option_mask32 & 0x20)
//#define DEBUG 1
+#define DEBUG 0
enum {
MAX_HOST_LEN = 16, // longest host name allowed is 15
};
static struct dns_entry *dnsentry = NULL;
-// FIXME! unused! :(
-static int daemonmode;
static uint32_t ttl = DEFAULT_TTL;
/*
}
}
-/*
- * Append message to log file
- */
-static void log_message(char *filename, char *message)
-{
- FILE *logfile;
- if (!daemonmode)
- return;
- logfile = fopen(filename, "a");
- if (!logfile)
- return;
- fprintf(logfile, "%s\n", message);
- fclose(logfile);
-}
-
/*
* Read one line of hostname/IP from file
* Returns 0 for each valid entry read, -1 at EOF
* Assumes all host names are lower case only
- * Hostnames with more than one label is not handled correctly.
+ * Hostnames with more than one label are not handled correctly.
* Presently the dot is copied into name without
* converting to a length/string substring for that label.
*/
static int getfileentry(FILE * fp, struct dns_entry *s)
{
unsigned int a,b,c,d;
- char *r, *name;
+ char *line, *r, *name;
restart:
- r = bb_get_line_from_file(fp);
+ line = r = xmalloc_fgets(fp);
if (!r)
return -1;
while (*r == ' ' || *r == '\t') {
r++;
- if (!*r || *r == '#' || *r == '\n')
+ if (!*r || *r == '#' || *r == '\n') {
+ free(line);
goto restart; /* skipping empty/blank and commented lines */
+ }
}
name = r;
while (*r != ' ' && *r != '\t')
r++;
- *r++ = 0;
- if (sscanf(r, "%u.%u.%u.%u", &a, &b, &c, &d) != 4)
+ *r++ = '\0';
+ if (sscanf(r, "%u.%u.%u.%u", &a, &b, &c, &d) != 4) {
+ free(line);
goto restart; /* skipping wrong lines */
+ }
sprintf(s->ip, "%u.%u.%u.%u", a, b, c, d);
sprintf(s->rip, ".%u.%u.%u.%u", d, c, b, a);
undot((uint8_t*)s->rip);
- convname(s->name,(uint8_t*)name);
+ convname(s->name, (uint8_t*)name);
if (OPT_verbose)
fprintf(stderr, "\tname:%s, ip:%s\n", &(s->name[1]),s->ip);
+ free(line);
return 0;
}
{
FILE *fp;
struct dns_entry *m, *prev;
- prev = dnsentry = NULL;
+ prev = dnsentry = NULL;
fp = xfopen(fileconf, "r");
while (1) {
- m = xmalloc(sizeof(struct dns_entry));
-
- m->next = NULL;
+ m = xzalloc(sizeof(*m));
+ /*m->next = NULL;*/
if (getfileentry(fp, m))
break;
fclose(fp);
}
-
-/*
- * Set up UDP socket
- */
-static int listen_socket(char *iface_addr, int listen_port)
-{
- struct sockaddr_in a;
- char msg[100];
- int s;
- int yes = 1;
- s = xsocket(PF_INET, SOCK_DGRAM, 0);
-#ifdef SO_REUSEADDR
- if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *)&yes, sizeof(yes)) < 0)
- bb_perror_msg_and_die("setsockopt() failed");
-#endif
- memset(&a, 0, sizeof(a));
- a.sin_port = htons(listen_port);
- a.sin_family = AF_INET;
- if (!inet_aton(iface_addr, &a.sin_addr))
- bb_perror_msg_and_die("bad iface address");
- xbind(s, (struct sockaddr *)&a, sizeof(a));
- xlisten(s, 50);
- sprintf(msg, "accepting UDP packets on addr:port %s:%d\n",
- iface_addr, (int)listen_port);
- log_message(LOG_FILE, msg);
- return s;
-}
-
/*
* Look query up in dns records and return answer if found
* qs is the query string, first byte the string length
struct dns_entry *d=dnsentry;
do {
-#ifdef DEBUG
+#if DEBUG
char *p,*q;
q = (char *)&(qs[1]);
p = &(d->name[1]);
- fprintf(stderr, "\n%s: %d/%d p:%s q:%s %d",
- __FUNCTION__, strlen(p), (int)(d->name[0]), p, q, strlen(q));
+ fprintf(stderr, "\n%s: %d/%d p:%s q:%s %d",
+ __FUNCTION__, (int)strlen(p), (int)(d->name[0]),
+ p, q, (int)strlen(q));
#endif
if (type == REQ_A) { /* search by host name */
for (i = 1; i <= (int)(d->name[0]); i++)
if (tolower(qs[i]) != d->name[i])
break;
if (i > (int)(d->name[0])) {
-#ifdef DEBUG
+#if DEBUG
fprintf(stderr, " OK");
#endif
strcpy((char *)as, d->ip);
-#ifdef DEBUG
+#if DEBUG
fprintf(stderr, " as:%s\n", as);
#endif
return 0;
}
- } else
+ } else
if (type == REQ_PTR) { /* search by IP-address */
if (!strncmp((char*)&d->rip[1], (char*)&qs[1], strlen(d->rip)-1)) {
strcpy((char *)as, d->name);
goto empty_packet;
// We have a standard query
- log_message(LOG_FILE, (char *)from);
+ bb_info_msg("%s", (char *)from);
lookup_result = table_lookup(type, answstr, (uint8_t*)from);
if (lookup_result != 0) {
outr.flags = 3 | 0x0400; //name do not exist and auth
static void interrupt(int x)
{
unlink(LOCK_FILE);
- write(2, "interrupt exiting\n", 18);
+ bb_error_msg("interrupt, exiting\n");
exit(2);
}
int dnsd_main(int argc, char **argv)
{
+ char *listen_interface = NULL;
+ char *sttl, *sport;
+ len_and_sockaddr *lsa;
int udps;
uint16_t port = 53;
uint8_t buf[MAX_PACK_LEN];
- char *listen_interface = "0.0.0.0";
- char *sttl, *sport;
getopt32(argc, argv, "i:c:t:p:dv", &listen_interface, &fileconf, &sttl, &sport);
//if (option_mask32 & 0x1) // -i
//if (option_mask32 & 0x2) // -c
if (option_mask32 & 0x4) // -t
- if (!(ttl = atol(sttl)))
- bb_show_usage();
+ ttl = xatou_range(sttl, 1, 0xffffffff);
if (option_mask32 & 0x8) // -p
- if (!(port = atol(sport)))
- bb_show_usage();
+ port = xatou_range(sttl, 1, 0xffff);
if (OPT_verbose) {
bb_info_msg("listen_interface: %s", listen_interface);
bb_info_msg("fileconf: %s", fileconf);
}
- if (OPT_daemon)
+ if (OPT_daemon) {
+//FIXME: NOMMU will NOT set LOGMODE_SYSLOG!
#ifdef BB_NOMMU
/* reexec for vfork() do continue parent */
vfork_daemon_rexec(1, 0, argc, argv, "-d");
#else
xdaemon(1, 0);
#endif
+ logmode = LOGMODE_SYSLOG;
+ }
dnsentryinit();
signal(SIGURG, SIG_IGN);
#endif
- udps = listen_socket(listen_interface, port);
- if (udps < 0)
- exit(1);
+ lsa = host2sockaddr(listen_interface, port);
+ udps = xsocket(lsa->sa.sa_family, SOCK_DGRAM, 0);
+ xbind(udps, &lsa->sa, lsa->len);
+ // xlisten(udps, 50); - ?!! DGRAM sockets are never listened on I think?
+ bb_info_msg("Accepting UDP packets on %s",
+ xmalloc_sockaddr2dotted(&lsa->sa, lsa->len));
while (1) {
fd_set fdset;
FD_ZERO(&fdset);
FD_SET(udps, &fdset);
// Block until a message arrives
+// FIXME: Fantastic. select'ing on just one fd??
+// Why no just block on it doing recvfrom() ?
r = select(udps + 1, &fdset, NULL, NULL, NULL);
if (r < 0)
bb_perror_msg_and_die("select error");
/* Can this test ever be false? - yes */
if (FD_ISSET(udps, &fdset)) {
- struct sockaddr_in from;
- int fromlen = sizeof(from);
- r = recvfrom(udps, buf, sizeof(buf), 0,
- (struct sockaddr *)&from,
- (void *)&fromlen);
+ socklen_t fromlen = lsa->len;
+// FIXME: need to get *DEST* address (to which of our addresses
+// this query was directed), and reply from the same address.
+// Or else we can exhibit usual UDP ugliness:
+// [ip1.multihomed.ip2] <= query to ip1 <= peer
+// [ip1.multihomed.ip2] => reply from ip2 => peer (confused)
+ r = recvfrom(udps, buf, sizeof(buf), 0, &lsa->sa, &fromlen);
if (OPT_verbose)
- fprintf(stderr, "\n--- Got UDP ");
- log_message(LOG_FILE, "\n--- Got UDP ");
+ bb_info_msg("Got UDP packet");
if (r < 12 || r > 512) {
bb_error_msg("invalid packet size");
continue;
}
- if (r > 0) {
- r = process_packet(buf);
- if (r > 0)
- sendto(udps, buf,
- r, 0, (struct sockaddr *)&from,
- fromlen);
- }
- } // end if
- } // end while
- return 0;
+ if (r <= 0)
+ continue;
+ r = process_packet(buf);
+ if (r <= 0)
+ continue;
+ sendto(udps, buf, r, 0, &lsa->sa, fromlen);
+ }
+ }
}
projects / oweals / busybox.git / blobdiff