dnsdomainname,hostname: make NOEXEC

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

diff --git a/networking/dnsd.c b/networking/dnsd.c
index c76a54f9e53fd7d79dc879e2e0cc01b5b8693c3e..37a80309d760e049333e7029504c67b2ad4a8e71 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.
@@ -16,6 +16,30 @@
  * Some bugfix and minor changes was applied by Roberto A. Foglietta who made
  * the first porting of oao' scdns to busybox also.
  */
+//config:config DNSD
+//config:      bool "dnsd (9.8 kb)"
+//config:      default y
+//config:      help
+//config:      Small and static DNS server daemon.
+
+//applet:IF_DNSD(APPLET(dnsd, BB_DIR_USR_SBIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_DNSD) += dnsd.o
+
+//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 +68,15 @@ 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;
@@ -174,7 +203,7 @@ static char *table_lookup(struct dns_entry *d,
                if ((len != 1 || d->name[1] != '*')
                /* we assume (do not check) that query_string
                 * ends in ".in-addr.arpa" */
-                && strncmp(d->rip, query_string, strlen(d->rip)) == 0
+                && is_prefixed_with(query_string, d->rip)
                ) {
 #if DEBUG
                        fprintf(stderr, "Found name:%s\n", d->name);
@@ -331,7 +360,7 @@ RDATA   a variable length string of octets that describes the resource.
 
 In order to reduce the size of messages, domain names coan be compressed.
 An entire domain name or a list of labels at the end of a domain name
-is replaced with a pointer to a prior occurance of the same name.
+is replaced with a pointer to a prior occurrence of the same name.
 
 The pointer takes the form of a two octet sequence:
     +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
@@ -383,7 +412,7 @@ 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);