dnsmasq: follow upstream dnsmasq pre-v2.81 v2

Backport upstream commits.  Most interesting 122392e which changes how
SERVFAIL is handled especially in event of genuine server down/failure
scenarios with multiple servers.  a799ca0 also interesting in that
answered received via TCP are now cached, DNSSEC typically using TCP
meant until now answers weren't cached, hence reducing performance.

59e4703 Free config file values on parsing errors.
48d12f1 Remove the NO_FORK compile-time option, and support for uclinux.
122392e Revert 68f6312d4bae30b78daafcd6f51dc441b8685b1e
3a5a84c Fix Makefile lines generating UBUS linker config.
24b8760 Do not rely on dead code elimination, use array instead. Make options bits derived from size and count. Use size of option bits and last supported bit in computation. No new change would be required when new options are added. Just change OPT_LAST constant.
6f7812d Fix spurious AD flags in some DNS replies from local config.
cbb5b17 Fix logging in cf5984367bc6a949e3803a576512c5a7bc48ebab
cf59843 Don't forward *.bind/*.server queries upstream
ee87504 Remove ability to compile without IPv6 support.
a220545 Ensure that AD bit is reset on answers from --address=/<domain>/<address>.
a799ca0 Impove cache behaviour for TCP connections.

Along with an additional patch to fix compilation without DHCPv6, sent
upstream.

I've been running this for aaaages without obvious issue hence brave
step of opening to wider openwrt community.

Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>

1 files changed, 71 insertions, 0 deletions

diff --git a/package/network/services/dnsmasq/patches/0007-Do-not-rely-on-dead-code-elimination-use-array-inste.patch b/package/network/services/dnsmasq/patches/0007-Do-not-rely-on-dead-code-elimination-use-array-inste.patch
new file mode 100644
index 0000000000..55ea917c39
--- /dev/null
+++ b/package/network/services/dnsmasq/patches/0007-Do-not-rely-on-dead-code-elimination-use-array-inste.patch
@@ -0,0 +1,71 @@
+From 24b87607c1353e94689e8a2190571ab3f3b36f31 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Petr=20Men=C5=A1=C3=ADk?= <pemensik@redhat.com>
+Date: Wed, 24 Oct 2018 22:30:18 +0100
+Subject: [PATCH 07/11] Do not rely on dead code elimination, use array
+ instead. Make options bits derived from size and count. Use size of option
+ bits and last supported bit in computation. No new change would be required
+ when new options are added. Just change OPT_LAST constant.
+
+Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
+---
+ src/dnsmasq.h | 11 +++++++----
+ src/option.c  | 10 ++--------
+ 2 files changed, 9 insertions(+), 12 deletions(-)
+
+--- a/src/dnsmasq.h
++++ b/src/dnsmasq.h
+@@ -200,9 +200,6 @@ struct event_desc {
+ #define EC_MISC        5
+ #define EC_INIT_OFFSET 10
+ 
+-/* Trust the compiler dead-code eliminator.... */
+-#define option_bool(x) (((x) < 32) ? daemon->options & (1u << (x)) : daemon->options2 & (1u << ((x) - 32)))
+-
+ #define OPT_BOGUSPRIV      0
+ #define OPT_FILTER         1
+ #define OPT_LOG            2
+@@ -264,6 +261,12 @@ struct event_desc {
+ #define OPT_UBUS           58
+ #define OPT_LAST           59
+ 
++#define OPTION_BITS (sizeof(unsigned int)*8)
++#define OPTION_SIZE ( (OPT_LAST/OPTION_BITS)+((OPT_LAST%OPTION_BITS)!=0) )
++#define option_var(x) (daemon->options[(x) / OPTION_BITS])
++#define option_val(x) ((1u) << ((x) % OPTION_BITS))
++#define option_bool(x) (option_var(x) & option_val(x))
++
+ /* extra flags for my_syslog, we use a couple of facilities since they are known 
+    not to occupy the same bits as priorities, no matter how syslog.h is set up. */
+ #define MS_TFTP   LOG_USER
+@@ -978,7 +981,7 @@ extern struct daemon {
+      config file arguments. All set (including defaults)
+      in option.c */
+ 
+-  unsigned int options, options2;
++  unsigned int options[OPTION_SIZE];
+   struct resolvc default_resolv, *resolv_files;
+   time_t last_resolv;
+   char *servers_file;
+--- a/src/option.c
++++ b/src/option.c
+@@ -1490,18 +1490,12 @@ static int parse_dhcp_opt(char *errstr,
+ 
+ void set_option_bool(unsigned int opt)
+ {
+-  if (opt < 32)
+-    daemon->options |= 1u << opt;
+-  else
+-    daemon->options2 |= 1u << (opt - 32);
++  option_var(opt) |= option_val(opt);
+ }
+ 
+ void reset_option_bool(unsigned int opt)
+ {
+-  if (opt < 32)
+-    daemon->options &= ~(1u << opt);
+-  else
+-    daemon->options2 &= ~(1u << (opt - 32));
++  option_var(opt) &= ~(option_val(opt));
+ }
+ 
+ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int command_line, int servers_only)