[PATCH] iptables: Constify option struct

[PATCH] iptables: Constify option struct

[Harsha Sharma]

The struct of type option is only used to initialise a field inside
the xtables_globals struct and is not modified anywhere.
Done using following coccinelle semantic patch

@r1 disable optional_qualifier@
identifier s,i;
position p;
@@

static struct option i@p[] ={...};

@ok1@
identifier r1.i;
expression e;
position p;
@@
e = i@p

@bad@
position p != {r1.p,ok1.p};
identifier r1.i;
@@
e@i@p

@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
static
+const
struct option i[] = { ... };

Signed-off-by: Harsha Sharma <harshasharmaiitr@gmail.com>
---
 iptables/ip6tables.c  | 2 +-
 iptables/iptables.c   | 2 +-
 iptables/xtables-eb.c | 2 +-
 iptables/xtables.c    | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/iptables/ip6tables.c b/iptables/ip6tables.c
index 49bd006..0f6fa31 100644
--- a/iptables/ip6tables.c
+++ b/iptables/ip6tables.c
@@ -78,7 +78,7 @@ static const char optflags[]
 
 static const char unsupported_rev[] = " [unsupported revision]";
 
-static struct option original_opts[] = {
+static const struct option original_opts[] = {
 	{.name = "append",        .has_arg = 1, .val = 'A'},
 	{.name = "delete",        .has_arg = 1, .val = 'D'},
 	{.name = "check" ,        .has_arg = 1, .val = 'C'},
diff --git a/iptables/iptables.c b/iptables/iptables.c
index 69d19fe..e930fe2 100644
--- a/iptables/iptables.c
+++ b/iptables/iptables.c
@@ -75,7 +75,7 @@ static const char optflags[]
 
 static const char unsupported_rev[] = " [unsupported revision]";
 
-static struct option original_opts[] = {
+static const struct option original_opts[] = {
 	{.name = "append",        .has_arg = 1, .val = 'A'},
 	{.name = "delete",        .has_arg = 1, .val = 'D'},
 	{.name = "check",         .has_arg = 1, .val = 'C'},
diff --git a/iptables/xtables-eb.c b/iptables/xtables-eb.c
index c8b5d4f..60ec935 100644
--- a/iptables/xtables-eb.c
+++ b/iptables/xtables-eb.c
@@ -247,7 +247,7 @@ static int get_current_chain(const char *chain)
 
 /* Default command line options. Do not mess around with the already
  * assigned numbers unless you know what you are doing */
-static struct option ebt_original_options[] =
+static const struct option ebt_original_options[] =
 {
 	{ "append"         , required_argument, 0, 'A' },
 	{ "insert"         , required_argument, 0, 'I' },
diff --git a/iptables/xtables.c b/iptables/xtables.c
index ac11325..aebe7d7 100644
--- a/iptables/xtables.c
+++ b/iptables/xtables.c
@@ -59,7 +59,7 @@ static const char cmdflags[] = { 'I', 'D', 'D', 'R', 'A', 'L', 'F', 'Z',
 static const char optflags[]
 = { 'n', 's', 'd', 'p', 'j', 'v', 'x', 'i', 'o', '0', 'c', 'f'};
 
-static struct option original_opts[] = {
+static const struct option original_opts[] = {
 	{.name = "append",	  .has_arg = 1, .val = 'A'},
 	{.name = "delete",	  .has_arg = 1, .val = 'D'},
 	{.name = "check",	  .has_arg = 1, .val = 'C'},
-- 
1.9.1

Re: [PATCH] iptables: Constify option struct

[Pablo Neira Ayuso]

On Wed, Sep 27, 2017 at 05:14:52PM +0530, Harsha Sharma wrote:
> The struct of type option is only used to initialise a field inside
> the xtables_globals struct and is not modified anywhere.
> Done using following coccinelle semantic patch

Applied, thanks.

[PATCH] iptables: Constify option struct

[Gargi Sharma]

The struct  of the type option is only used to initialise a field
inside the xtables_match struct and is not modified anywhere.
Done using Coccinelle:

@r1 disable optional_qualifier@
identifier s,i;
position p;
@@

static struct option i@p[] ={...};

@ok1@
identifier r1.i;
expression e;
position p;
@@
e = i@p

@bad@
position p != {r1.p,ok1.p};
identifier r1.i;
@@
e@i@p

@depends on !bad disable optional_qualifier@
identifier r1.i;
@@
static
+const
struct option i[] = { ... };

Signed-off-by: Gargi Sharma <gs051095@gmail.com>
---
 extensions/libebt_limit.c  | 2 +-
 extensions/libebt_mark.c   | 2 +-
 extensions/libebt_mark_m.c | 2 +-
 extensions/libebt_nflog.c  | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/extensions/libebt_limit.c b/extensions/libebt_limit.c
index 6b9bb16..988f678 100644
--- a/extensions/libebt_limit.c
+++ b/extensions/libebt_limit.c
@@ -29,7 +29,7 @@
 #define ARG_LIMIT		'1'
 #define ARG_LIMIT_BURST		'2'
 
-static struct option brlimit_opts[] =
+static const struct option brlimit_opts[] =
 {
 	{ .name = "limit",	.has_arg = true,	.val = ARG_LIMIT },
 	{ .name = "limit-burst",.has_arg = true,	.val = ARG_LIMIT_BURST },
diff --git a/extensions/libebt_mark.c b/extensions/libebt_mark.c
index a1a208c..7b80b22 100644
--- a/extensions/libebt_mark.c
+++ b/extensions/libebt_mark.c
@@ -25,7 +25,7 @@ static int mark_supplied;
 #define MARK_ORMARK  '3'
 #define MARK_ANDMARK '4'
 #define MARK_XORMARK '5'
-static struct option brmark_opts[] = {
+static const struct option brmark_opts[] = {
 	{ .name = "mark-target",.has_arg = true,	.val = MARK_TARGET },
 	/* an oldtime messup, we should have always used the scheme
 	 * <extension-name>-<option> */
diff --git a/extensions/libebt_mark_m.c b/extensions/libebt_mark_m.c
index ab9d234..eb08dba 100644
--- a/extensions/libebt_mark_m.c
+++ b/extensions/libebt_mark_m.c
@@ -18,7 +18,7 @@
 
 #define MARK '1'
 
-static struct option brmark_m_opts[] = {
+static const struct option brmark_m_opts[] = {
 	{ .name = "mark",	.has_arg = true, .val = MARK },
 	XT_GETOPT_TABLEEND,
 };
diff --git a/extensions/libebt_nflog.c b/extensions/libebt_nflog.c
index fef7196..5f1d13b 100644
--- a/extensions/libebt_nflog.c
+++ b/extensions/libebt_nflog.c
@@ -30,7 +30,7 @@ enum {
 	NFLOG_NFLOG	= 0x16,
 };
 
-static struct option brnflog_opts[] = {
+static const struct option brnflog_opts[] = {
 	{ .name = "nflog-group",     .has_arg = true,  .val = NFLOG_GROUP},
 	{ .name = "nflog-prefix",    .has_arg = true,  .val = NFLOG_PREFIX},
 	{ .name = "nflog-range",     .has_arg = true,  .val = NFLOG_RANGE},
-- 
2.7.4

Re: [PATCH] iptables: Constify option struct

[Pablo Neira Ayuso]

On Tue, Mar 28, 2017 at 12:40:15AM +0530, Gargi Sharma wrote:
> The struct  of the type option is only used to initialise a field
> inside the xtables_match struct and is not modified anywhere.
> Done using Coccinelle:
> 
> @r1 disable optional_qualifier@
> identifier s,i;
> position p;
> @@
> 
> static struct option i@p[] ={...};
> 
> @ok1@
> identifier r1.i;
> expression e;
> position p;
> @@
> e = i@p
> 
> @bad@
> position p != {r1.p,ok1.p};
> identifier r1.i;
> @@
> e@i@p
> 
> @depends on !bad disable optional_qualifier@
> identifier r1.i;
> @@
> static
> +const
> struct option i[] = { ... };

Applied, thanks.

You can probably have a look at ebtables.git, probably there are more
things to constify there.