udhcpc: add support for DHCP option 212 (RFC 5969)

[oweals/busybox.git] / networking / dnsd.c

diff --git a/networking/dnsd.c b/networking/dnsd.c
index 6771c53461b2ce2b7e285f45da59340f7af2c1e7..fe98400f7d6047fc38c40e02f317afa8e51b4c2d 100644 (file)
--- a/networking/dnsd.c
+++ b/networking/dnsd.c
@@ -6,7 +6,7 @@
  * Copyright (C) 2005 Odd Arild Olsen (oao at fibula dot no)
  * Copyright (C) 2003 Paul Sheer
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  *
  * Odd Arild Olsen started out with the sheerdns [1] of Paul Sheer and rewrote
  * it into a shape which I believe is both easier to understand and maintain.
@@ -17,6 +17,21 @@
  * the first porting of oao' scdns to busybox also.
  */
 
+//usage:#define dnsd_trivial_usage
+//usage:       "[-dvs] [-c CONFFILE] [-t TTL_SEC] [-p PORT] [-i ADDR]"
+//usage:#define dnsd_full_usage "\n\n"
+//usage:       "Small static DNS server daemon\n"
+//usage:     "\n       -c FILE Config file"
+//usage:     "\n       -t SEC  TTL"
+//usage:     "\n       -p PORT Listen on PORT"
+//usage:     "\n       -i ADDR Listen on ADDR"
+//usage:     "\n       -d      Daemonize"
+//usage:     "\n       -v      Verbose"
+//usage:     "\n       -s      Send successful replies only. Use this if you want"
+//usage:     "\n               to use /etc/resolv.conf with two nameserver lines:"
+//usage:     "\n                       nameserver DNSD_SERVER"
+//usage:     "\n                       nameserver NORMAL_DNS_SERVER"
+
 #include "libbb.h"
 #include <syslog.h>
 
@@ -44,10 +59,15 @@ struct dns_head {
        uint16_t nauth;
        uint16_t nadd;
 };
+/* Structure used to access type and class fields.
+ * They are totally unaligned, but gcc 4.3.4 thinks that pointer of type uint16_t*
+ * is 16-bit aligned and replaces 16-bit memcpy (in move_from_unaligned16 macro)
+ * with aligned halfword access on arm920t!
+ * Oh well. Slapping PACKED everywhere seems to help: */
 struct type_and_class {
-       uint16_t type;
-       uint16_t class;
-};
+       uint16_t type PACKED;
+       uint16_t class PACKED;
+} PACKED;
 /* element of known name, ip address and reversed ip address */
 struct dns_entry {
        struct dns_entry *next;
@@ -383,7 +403,7 @@ static int process_packet(struct dns_entry *conf_data,
        query_len = strlen(query_string) + 1;
        /* may be unaligned! */
        unaligned_type_class = (void *)(query_string + query_len);
-       query_len += sizeof(unaligned_type_class);
+       query_len += sizeof(*unaligned_type_class);
        /* where to append answer block */
        answb = (void *)(unaligned_type_class + 1);
 
@@ -480,7 +500,8 @@ int dnsd_main(int argc UNUSED_PARAM, char **argv)
        unsigned lsa_size;
        int udps, opts;
        uint16_t port = 53;
-       uint8_t buf[MAX_PACK_LEN + 1];
+       /* Ensure buf is 32bit aligned (we need 16bit, but 32bit can't hurt) */
+       uint8_t buf[MAX_PACK_LEN + 1] ALIGN4;
 
        opts = getopt32(argv, "vsi:c:t:p:d", &listen_interface, &fileconf, &sttl, &sport);
        //if (opts & (1 << 0)) // -v