netfilter 56/62: xtables: add const qualifiers

Patrick McHardy
2010-02-16T14:56:35Z

commit d5d1baa15f5b05e9110403724d5dc72d6d541e04
Author: Jan Engelhardt <jengelh@medozas.de>
Date: Fri Jun 26 07:51:59 2009 +0200

netfilter: xtables: add const qualifiers

This should make it easier to remove redundant arguments later.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 208f4e3..bcdf02d 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -82,7 +82,8 @@ static inline int ebt_do_match (struct ebt_entry_match *m,
return m->u.match->match(skb, par) ? EBT_MATCH : EBT_NOMATCH;
}

-static inline int ebt_dev_check(char *entry, const struct net_device *device)
+static inline int
+ebt_dev_check(const char *entry, const struct net_device *device)
{
int i = 0;
const char *devname;
@@ -100,8 +101,9 @@ static inline int ebt_dev_check(char *entry, const struct net_device *device)

#define FWINV2(bool,invflg) ((bool) ^ !!(e->invflags & invflg))
/* process standard matches */
-static inline int ebt_basic_match(struct ebt_entry *e, struct ethhdr *h,
- const struct net_device *in, const struct net_device *out)
+static inline int
+ebt_basic_match(const struct ebt_entry *e, const struct ethhdr *h,
+ const struct net_device *in, const struct net_device *out)
{
int verdict, i;

@@ -156,12 +158,12 @@ unsigned int ebt_do_table (unsigned int hook, struct sk_buff *skb,
int i, nentries;
struct ebt_entry *point;
struct ebt_counter *counter_base, *cb_base;
- struct ebt_entry_target *t;
+ const struct ebt_entry_target *t;
int verdict, sp = 0;
struct ebt_chainstack *cs;
struct ebt_entries *chaininfo;
- char *base;
- struct ebt_table_info *private;
+ const char *base;
+ const struct ebt_table_info *private;
bool hotdrop = false;
struct xt_match_param mtpar;
struct xt_target_param tgpar;
@@ -395,7 +397,7 @@ ebt_check_watcher(struct ebt_entry_watcher *w, struct xt_tgchk_param *par,
return 0;
}

-static int ebt_verify_pointers(struct ebt_replace *repl,
+static int ebt_verify_pointers(const struct ebt_replace *repl,
struct ebt_table_info *newinfo)
{
unsigned int limit = repl->entries_size;
@@ -466,8 +468,8 @@ static int ebt_verify_pointers(struct ebt_replace *repl,
* to parse the userspace data
*/
static inline int
-ebt_check_entry_size_and_hooks(struct ebt_entry *e,
- struct ebt_table_info *newinfo,
+ebt_check_entry_size_and_hooks(const struct ebt_entry *e,
+ const struct ebt_table_info *newinfo,
unsigned int *n, unsigned int *cnt,
unsigned int *totalcnt, unsigned int *udc_cnt)
{
@@ -622,9 +624,8 @@ ebt_cleanup_entry(struct ebt_entry *e, struct net *net, unsigned int *cnt)
}

static inline int
-ebt_check_entry(struct ebt_entry *e,
- struct net *net,
- struct ebt_table_info *newinfo,
+ebt_check_entry(struct ebt_entry *e, struct net *net,
+ const struct ebt_table_info *newinfo,
const char *name, unsigned int *cnt,
struct ebt_cl_stack *cl_s, unsigned int udc_cnt)
{
@@ -743,12 +744,12 @@ cleanup_matches:
* the hook mask for udc tells us from which base chains the udc can be
* accessed. This mask is a parameter to the check() functions of the extensions
*/
-static int check_chainloops(struct ebt_entries *chain, struct ebt_cl_stack *cl_s,
+static int check_chainloops(const struct ebt_entries *chain, struct ebt_cl_stack *cl_s,
unsigned int udc_cnt, unsigned int hooknr, char *base)
{
int i, chain_nr = -1, pos = 0, nentries = chain->nentries, verdict;
- struct ebt_entry *e = (struct ebt_entry *)chain->data;
- struct ebt_entry_target *t;
+ const struct ebt_entry *e = (struct ebt_entry *)chain->data;
+ const struct ebt_entry_target *t;

while (pos < nentries || chain_nr != -1) {
/* end of udc, go back one 'recursion' step */
@@ -814,7 +815,7 @@ letscontinue:
}

/* do the parsing of the table/chains/entries/matches/watchers/targets, heh */
-static int translate_table(struct net *net, char *name,
+static int translate_table(struct net *net, const char *name,
struct ebt_table_info *newinfo)
{
unsigned int i, j, k, udc_cnt;
@@ -934,7 +935,7 @@ static int translate_table(struct net *net, char *name,
}

/* called under write_lock */
-static void get_counters(struct ebt_counter *oldcounters,
+static void get_counters(const struct ebt_counter *oldcounters,
struct ebt_counter *counters, unsigned int nentries)
{
int i, cpu;
@@ -957,7 +958,8 @@ static void get_counters(struct ebt_counter *oldcounters,
}

/* replace the table */
-static int do_replace(struct net *net, void __user *user, unsigned int len)
+static int do_replace(struct net *net, const void __user *user,
+ unsigned int len)
{
int ret, i, countersize;
struct ebt_table_info *newinfo;
@@ -1237,7 +1239,8 @@ void ebt_unregister_table(struct net *net, struct ebt_table *table)
}

/* userspace just supplied us with counters */
-static int update_counters(struct net *net, void __user *user, unsigned int len)
+static int update_counters(struct net *net, const void __user *user,
+ unsigned int len)
{
int i, ret;
struct ebt_counter *tmp;
@@ -1292,8 +1295,8 @@ free_tmp:
return ret;
}

-static inline int ebt_make_matchname(struct ebt_entry_match *m,
- char *base, char __user *ubase)
+static inline int ebt_make_matchname(const struct ebt_entry_match *m,
+ const char *base, char __user *ubase)
{
char __user *hlp = ubase + ((char *)m - base);
if (copy_to_user(hlp, m->u.match->name, EBT_FUNCTION_MAXNAMELEN))
@@ -1301,8 +1304,8 @@ static inline int ebt_make_matchname(struct ebt_entry_match *m,
return 0;
}

-static inline int ebt_make_watchername(struct ebt_entry_watcher *w,
- char *base, char __user *ubase)
+static inline int ebt_make_watchername(const struct ebt_entry_watcher *w,
+ const char *base, char __user *ubase)
{
char __user *hlp = ubase + ((char *)w - base);
if (copy_to_user(hlp , w->u.watcher->name, EBT_FUNCTION_MAXNAMELEN))
@@ -1310,11 +1313,12 @@ static inline int ebt_make_watchername(struct ebt_entry_watcher *w,
return 0;
}

-static inline int ebt_make_names(struct ebt_entry *e, char *base, char __user *ubase)
+static inline int
+ebt_make_names(struct ebt_entry *e, const char *base, char __user *ubase)
{
int ret;
char __user *hlp;
- struct ebt_entry_target *t;
+ const struct ebt_entry_target *t;

if (e->bitmask == 0)
return 0;
@@ -1335,10 +1339,11 @@ static inline int ebt_make_names(struct ebt_entry *e, char *base, char __user *u

/* called with ebt_mutex locked */
static int copy_everything_to_user(struct ebt_table *t, void __user *user,
- int *len, int cmd)
+ const int *len, int cmd)
{
struct ebt_replace tmp;
- struct ebt_counter *counterstmp, *oldcounters;
+ struct ebt_counter *counterstmp;
+ const struct ebt_counter *oldcounters;
unsigned int entries_size, nentries;
char *entries;

diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 2303dc9..4db5c1e 100644
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -233,7 +233,14 @@ arpt_error(struct sk_buff *skb, const struct xt_target_param *par)
return NF_DROP;
}

-static inline struct arpt_entry *get_entry(void *base, unsigned int offset)
+static inline const struct arpt_entry_target *
+arpt_get_target_c(const struct arpt_entry *e)
+{
+ return arpt_get_target((struct arpt_entry *)e);
+}
+
+static inline struct arpt_entry *
+get_entry(const void *base, unsigned int offset)
{
return (struct arpt_entry *)(base + offset);
}
@@ -280,7 +287,7 @@ unsigned int arpt_do_table(struct sk_buff *skb,

arp = arp_hdr(skb);
do {
- struct arpt_entry_target *t;
+ const struct arpt_entry_target *t;
int hdr_len;

if (!arp_packet_match(arp, skb->dev, indev, outdev, &e->arp)) {
@@ -292,7 +299,7 @@ unsigned int arpt_do_table(struct sk_buff *skb,
(2 * skb->dev->addr_len);
ADD_COUNTER(e->counters, hdr_len, 1);

- t = arpt_get_target(e);
+ t = arpt_get_target_c(e);

/* Standard target? */
if (!t->u.kernel.target->target) {
@@ -358,7 +365,7 @@ static inline bool unconditional(const struct arpt_arp *arp)
/* Figures out from what hook each rule can be called: returns 0 if
* there are loops. Puts hook bitmask in comefrom.
*/
-static int mark_source_chains(struct xt_table_info *newinfo,
+static int mark_source_chains(const struct xt_table_info *newinfo,
unsigned int valid_hooks, void *entry0)
{
unsigned int hook;
@@ -379,7 +386,7 @@ static int mark_source_chains(struct xt_table_info *newinfo,

for (;;) {
const struct arpt_standard_target *t
- = (void *)arpt_get_target(e);
+ = (void *)arpt_get_target_c(e);
int visited = e->comefrom & (1 << hook);

if (e->comefrom & (1 << NF_ARP_NUMHOOKS)) {
@@ -463,7 +470,7 @@ static int mark_source_chains(struct xt_table_info *newinfo,
return 1;
}

-static inline int check_entry(struct arpt_entry *e, const char *name)
+static inline int check_entry(const struct arpt_entry *e, const char *name)
{
const struct arpt_entry_target *t;

@@ -475,7 +482,7 @@ static inline int check_entry(struct arpt_entry *e, const char *name)
if (e->target_offset + sizeof(struct arpt_entry_target) > e->next_offset)
return -EINVAL;

- t = arpt_get_target(e);
+ t = arpt_get_target_c(e);
if (e->target_offset + t->u.target_size > e->next_offset)
return -EINVAL;

@@ -540,14 +547,14 @@ out:
return ret;
}

-static bool check_underflow(struct arpt_entry *e)
+static bool check_underflow(const struct arpt_entry *e)
{
const struct arpt_entry_target *t;
unsigned int verdict;

if (!unconditional(&e->arp))
return false;
- t = arpt_get_target(e);
+ t = arpt_get_target_c(e);
if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
return false;
verdict = ((struct arpt_standard_target *)t)->verdict;
@@ -557,8 +564,8 @@ static bool check_underflow(struct arpt_entry *e)

static inline int check_entry_size_and_hooks(struct arpt_entry *e,
struct xt_table_info *newinfo,
- unsigned char *base,
- unsigned char *limit,
+ const unsigned char *base,
+ const unsigned char *limit,
const unsigned int *hook_entries,
const unsigned int *underflows,
unsigned int valid_hooks,
@@ -768,11 +775,11 @@ static void get_counters(const struct xt_table_info *t,
local_bh_enable();
}

-static struct xt_counters *alloc_counters(struct xt_table *table)
+static struct xt_counters *alloc_counters(const struct xt_table *table)
{
unsigned int countersize;
struct xt_counters *counters;
- struct xt_table_info *private = table->private;
+ const struct xt_table_info *private = table->private;

/* We need atomic snapshot of counters: rest doesn't change
* (other than comefrom, which userspace doesn't care
@@ -790,11 +797,11 @@ static struct xt_counters *alloc_counters(struct xt_table *table)
}

static int copy_entries_to_user(unsigned int total_size,
- struct xt_table *table,
+ const struct xt_table *table,
void __user *userptr)
{
unsigned int off, num;
- struct arpt_entry *e;
+ const struct arpt_entry *e;
struct xt_counters *counters;
struct xt_table_info *private = table->private;
int ret = 0;
@@ -814,7 +821,7 @@ static int copy_entries_to_user(unsigned int total_size,
/* FIXME: use iterator macros --RR */
/* ... then go back and fix counters and names */
for (off = 0, num = 0; off < total_size; off += e->next_offset, num++){
- struct arpt_entry_target *t;
+ const struct arpt_entry_target *t;

e = (struct arpt_entry *)(loc_cpu_entry + off);
if (copy_to_user(userptr + off
@@ -825,7 +832,7 @@ static int copy_entries_to_user(unsigned int total_size,
goto free_counters;
}

- t = arpt_get_target(e);
+ t = arpt_get_target_c(e);
if (copy_to_user(userptr + off + e->target_offset
+ offsetof(struct arpt_entry_target,
u.user.name),
@@ -860,18 +867,18 @@ static int compat_standard_to_user(void __user *dst, const void *src)
return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
}

-static int compat_calc_entry(struct arpt_entry *e,
+static int compat_calc_entry(const struct arpt_entry *e,
const struct xt_table_info *info,
- void *base, struct xt_table_info *newinfo)
+ const void *base, struct xt_table_info *newinfo)
{
- struct arpt_entry_target *t;
+ const struct arpt_entry_target *t;
unsigned int entry_offset;
int off, i, ret;

off = sizeof(struct arpt_entry) - sizeof(struct compat_arpt_entry);
entry_offset = (void *)e - base;

- t = arpt_get_target(e);
+ t = arpt_get_target_c(e);
off += xt_compat_target_offset(t->u.kernel.target);
newinfo->size -= off;
ret = xt_compat_add_offset(NFPROTO_ARP, entry_offset, off);
@@ -907,7 +914,8 @@ static int compat_table_info(const struct xt_table_info *info,
}
#endif

-static int get_info(struct net *net, void __user *user, int *len, int compat)
+static int get_info(struct net *net, void __user *user,
+ const int *len, int compat)
{
char name[ARPT_TABLE_MAXNAMELEN];
struct xt_table *t;
@@ -966,7 +974,7 @@ static int get_info(struct net *net, void __user *user, int *len, int compat)
}

static int get_entries(struct net *net, struct arpt_get_entries __user *uptr,
- int *len)
+ const int *len)
{
int ret;
struct arpt_get_entries get;
@@ -1080,7 +1088,8 @@ static int __do_replace(struct net *net, const char *name,
return ret;
}

-static int do_replace(struct net *net, void __user *user, unsigned int len)
+static int do_replace(struct net *net, const void __user *user,
+ unsigned int len)
{
int ret;
struct arpt_replace tmp;
@@ -1140,8 +1149,8 @@ add_counter_to_entry(struct arpt_entry *e,
return 0;
}

-static int do_add_counters(struct net *net, void __user *user, unsigned int len,
- int compat)
+static int do_add_counters(struct net *net, const void __user *user,
+ unsigned int len, int compat)
{
unsigned int i, curcpu;
struct xt_counters_info tmp;
@@ -1245,10 +1254,10 @@ static inline int
check_compat_entry_size_and_hooks(struct compat_arpt_entry *e,
struct xt_table_info *newinfo,
unsigned int *size,
- unsigned char *base,
- unsigned char *limit,
- unsigned int *hook_entries,
- unsigned int *underflows,
+ const unsigned char *base,
+ const unsigned char *limit,
+ const unsigned int *hook_entries,
+ const unsigned int *underflows,
unsigned int *i,
const char *name)
{
diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 2a4f745..e94c18b 100644
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -176,7 +176,7 @@ ipt_error(struct sk_buff *skb, const struct xt_target_param *par)

/* Performance critical - called for every packet */
static inline bool
-do_match(struct ipt_entry_match *m, const struct sk_buff *skb,
+do_match(const struct ipt_entry_match *m, const struct sk_buff *skb,
struct xt_match_param *par)
{
par->match = m->u.kernel.match;
@@ -191,7 +191,7 @@ do_match(struct ipt_entry_match *m, const struct sk_buff *skb,

/* Performance critical */
static inline struct ipt_entry *
-get_entry(void *base, unsigned int offset)
+get_entry(const void *base, unsigned int offset)
{
return (struct ipt_entry *)(base + offset);
}
@@ -206,6 +206,13 @@ static inline bool unconditional(const struct ipt_ip *ip)
#undef FWINV
}

+/* for const-correctness */
+static inline const struct ipt_entry_target *
+ipt_get_target_c(const struct ipt_entry *e)
+{
+ return ipt_get_target((struct ipt_entry *)e);
+}
+
#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
static const char *const hooknames[] = {
@@ -240,11 +247,11 @@ static struct nf_loginfo trace_loginfo = {

/* Mildly perf critical (only if packet tracing is on) */
static inline int
-get_chainname_rulenum(struct ipt_entry *s, struct ipt_entry *e,
+get_chainname_rulenum(const struct ipt_entry *s, const struct ipt_entry *e,
const char *hookname, const char **chainname,
const char **comment, unsigned int *rulenum)
{
- struct ipt_standard_target *t = (void *)ipt_get_target(s);
+ const struct ipt_standard_target *t = (void *)ipt_get_target_c(s);

if (strcmp(t->target.u.kernel.target->name, IPT_ERROR_TARGET) == 0) {
/* Head of user chain: ERROR target with chainname */
@@ -270,15 +277,15 @@ get_chainname_rulenum(struct ipt_entry *s, struct ipt_entry *e,
return 0;
}

-static void trace_packet(struct sk_buff *skb,
+static void trace_packet(const struct sk_buff *skb,
unsigned int hook,
const struct net_device *in,
const struct net_device *out,
const char *tablename,
- struct xt_table_info *private,
- struct ipt_entry *e)
+ const struct xt_table_info *private,
+ const struct ipt_entry *e)
{
- void *table_base;
+ const void *table_base;
const struct ipt_entry *root;
const char *hookname, *chainname, *comment;
unsigned int rulenum = 0;
@@ -322,9 +329,9 @@ ipt_do_table(struct sk_buff *skb,
/* Initializing verdict to NF_DROP keeps gcc happy. */
unsigned int verdict = NF_DROP;
const char *indev, *outdev;
- void *table_base;
+ const void *table_base;
struct ipt_entry *e, *back;
- struct xt_table_info *private;
+ const struct xt_table_info *private;
struct xt_match_param mtpar;
struct xt_target_param tgpar;

@@ -357,7 +364,7 @@ ipt_do_table(struct sk_buff *skb,
back = get_entry(table_base, private->underflow[hook]);

do {
- struct ipt_entry_target *t;
+ const struct ipt_entry_target *t;

IP_NF_ASSERT(e);
IP_NF_ASSERT(back);
@@ -450,7 +457,7 @@ ipt_do_table(struct sk_buff *skb,
/* Figures out from what hook each rule can be called: returns 0 if
there are loops. Puts hook bitmask in comefrom. */
static int
-mark_source_chains(struct xt_table_info *newinfo,
+mark_source_chains(const struct xt_table_info *newinfo,
unsigned int valid_hooks, void *entry0)
{
unsigned int hook;
@@ -468,8 +475,8 @@ mark_source_chains(struct xt_table_info *newinfo,
e->counters.pcnt = pos;

for (;;) {
- struct ipt_standard_target *t
- = (void *)ipt_get_target(e);
+ const struct ipt_standard_target *t
+ = (void *)ipt_get_target_c(e);
int visited = e->comefrom & (1 << hook);

if (e->comefrom & (1 << NF_INET_NUMHOOKS)) {
@@ -578,9 +585,9 @@ cleanup_match(struct ipt_entry_match *m, struct net *net, unsigned int *i)
}

static int
-check_entry(struct ipt_entry *e, const char *name)
+check_entry(const struct ipt_entry *e, const char *name)
{
- struct ipt_entry_target *t;
+ const struct ipt_entry_target *t;

if (!ip_checkentry(&e->ip)) {
duprintf("ip_tables: ip check failed %p %s.\n", e, name);
@@ -591,7 +598,7 @@ check_entry(struct ipt_entry *e, const char *name)
e->next_offset)
return -EINVAL;

- t = ipt_get_target(e);
+ t = ipt_get_target_c(e);
if (e->target_offset + t->u.target_size > e->next_offset)
return -EINVAL;

@@ -718,14 +725,14 @@ find_check_entry(struct ipt_entry *e, struct net *net, const char *name,
return ret;
}

-static bool check_underflow(struct ipt_entry *e)
+static bool check_underflow(const struct ipt_entry *e)
{
const struct ipt_entry_target *t;
unsigned int verdict;

if (!unconditional(&e->ip))
return false;
- t = ipt_get_target(e);
+ t = ipt_get_target_c(e);
if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
return false;
verdict = ((struct ipt_standard_target *)t)->verdict;
@@ -736,8 +743,8 @@ static bool check_underflow(struct ipt_entry *e)
static int
check_entry_size_and_hooks(struct ipt_entry *e,
struct xt_table_info *newinfo,
- unsigned char *base,
- unsigned char *limit,
+ const unsigned char *base,
+ const unsigned char *limit,
const unsigned int *hook_entries,
const unsigned int *underflows,
unsigned int valid_hooks,
@@ -952,11 +959,11 @@ get_counters(const struct xt_table_info *t,
local_bh_enable();
}

-static struct xt_counters * alloc_counters(struct xt_table *table)
+static struct xt_counters *alloc_counters(const struct xt_table *table)
{
unsigned int countersize;
struct xt_counters *counters;
- struct xt_table_info *private = table->private;
+ const struct xt_table_info *private = table->private;

/* We need atomic snapshot of counters: rest doesn't change
(other than comefrom, which userspace doesn't care
@@ -974,11 +981,11 @@ static struct xt_counters * alloc_counters(struct xt_table *table)

static int
copy_entries_to_user(unsigned int total_size,
- struct xt_table *table,
+ const struct xt_table *table,
void __user *userptr)
{
unsigned int off, num;
- struct ipt_entry *e;
+ const struct ipt_entry *e;
struct xt_counters *counters;
const struct xt_table_info *private = table->private;
int ret = 0;
@@ -1030,7 +1037,7 @@ copy_entries_to_user(unsigned int total_size,
}
}

- t = ipt_get_target(e);
+ t = ipt_get_target_c(e);
if (copy_to_user(userptr + off + e->target_offset
+ offsetof(struct ipt_entry_target,
u.user.name),
@@ -1066,24 +1073,24 @@ static int compat_standard_to_user(void __user *dst, const void *src)
}

static inline int
-compat_calc_match(struct ipt_entry_match *m, int *size)
+compat_calc_match(const struct ipt_entry_match *m, int *size)
{
*size += xt_compat_match_offset(m->u.kernel.match);
return 0;
}

-static int compat_calc_entry(struct ipt_entry *e,
+static int compat_calc_entry(const struct ipt_entry *e,
const struct xt_table_info *info,
- void *base, struct xt_table_info *newinfo)
+ const void *base, struct xt_table_info *newinfo)
{
- struct ipt_entry_target *t;
+ const struct ipt_entry_target *t;
unsigned int entry_offset;
int off, i, ret;

off = sizeof(struct ipt_entry) - sizeof(struct compat_ipt_entry);
entry_offset = (void *)e - base;
IPT_MATCH_ITERATE(e, compat_calc_match, &off);
- t = ipt_get_target(e);
+ t = ipt_get_target_c(e);
off += xt_compat_target_offset(t->u.kernel.target);
newinfo->size -= off;
ret = xt_compat_add_offset(AF_INET, entry_offset, off);
@@ -1119,7 +1126,8 @@ static int compat_table_info(const struct xt_table_info *info,
}
#endif

-static int get_info(struct net *net, void __user *user, int *len, int compat)
+static int get_info(struct net *net, void __user *user,
+ const int *len, int compat)
{
char name[IPT_TABLE_MAXNAMELEN];
struct xt_table *t;
@@ -1179,7 +1187,8 @@ static int get_info(struct net *net, void __user *user, int *len, int compat)
}

static int
-get_entries(struct net *net, struct ipt_get_entries __user *uptr, int *len)
+get_entries(struct net *net, struct ipt_get_entries __user *uptr,
+ const int *len)
{
int ret;
struct ipt_get_entries get;
@@ -1289,7 +1298,7 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks,
}

static int
-do_replace(struct net *net, void __user *user, unsigned int len)
+do_replace(struct net *net, const void __user *user, unsigned int len)
{
int ret;
struct ipt_replace tmp;
@@ -1350,7 +1359,8 @@ add_counter_to_entry(struct ipt_entry *e,
}

static int
-do_add_counters(struct net *net, void __user *user, unsigned int len, int compat)
+do_add_counters(struct net *net, const void __user *user,
+ unsigned int len, int compat)
{
unsigned int i, curcpu;
struct xt_counters_info tmp;
@@ -1546,10 +1556,10 @@ static int
check_compat_entry_size_and_hooks(struct compat_ipt_entry *e,
struct xt_table_info *newinfo,
unsigned int *size,
- unsigned char *base,
- unsigned char *limit,
- unsigned int *hook_entries,
- unsigned int *underflows,
+ const unsigned char *base,
+ const unsigned char *limit,
+ const unsigned int *hook_entries,
+ const unsigned int *underflows,
unsigned int *i,
const char *name)
{
diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c
index 3ff4fd5..4185099 100644
--- a/net/ipv6/netfilter/ip6_tables.c
+++ b/net/ipv6/netfilter/ip6_tables.c
@@ -208,7 +208,7 @@ ip6t_error(struct sk_buff *skb, const struct xt_target_param *par)

/* Performance critical - called for every packet */
static inline bool
-do_match(struct ip6t_entry_match *m, const struct sk_buff *skb,
+do_match(const struct ip6t_entry_match *m, const struct sk_buff *skb,
struct xt_match_param *par)
{
par->match = m->u.kernel.match;
@@ -222,7 +222,7 @@ do_match(struct ip6t_entry_match *m, const struct sk_buff *skb,
}

static inline struct ip6t_entry *
-get_entry(void *base, unsigned int offset)
+get_entry(const void *base, unsigned int offset)
{
return (struct ip6t_entry *)(base + offset);
}
@@ -236,6 +236,12 @@ static inline bool unconditional(const struct ip6t_ip6 *ipv6)
return memcmp(ipv6, &uncond, sizeof(uncond)) == 0;
}

+static inline const struct ip6t_entry_target *
+ip6t_get_target_c(const struct ip6t_entry *e)
+{
+ return ip6t_get_target((struct ip6t_entry *)e);
+}
+
#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)
/* This cries for unification! */
@@ -271,11 +277,11 @@ static struct nf_loginfo trace_loginfo = {

/* Mildly perf critical (only if packet tracing is on) */
static inline int
-get_chainname_rulenum(struct ip6t_entry *s, struct ip6t_entry *e,
+get_chainname_rulenum(const struct ip6t_entry *s, const struct ip6t_entry *e,
const char *hookname, const char **chainname,
const char **comment, unsigned int *rulenum)
{
- struct ip6t_standard_target *t = (void *)ip6t_get_target(s);
+ const struct ip6t_standard_target *t = (void *)ip6t_get_target_c(s);

if (strcmp(t->target.u.kernel.target->name, IP6T_ERROR_TARGET) == 0) {
/* Head of user chain: ERROR target with chainname */
@@ -301,15 +307,15 @@ get_chainname_rulenum(struct ip6t_entry *s, struct ip6t_entry *e,
return 0;
}

-static void trace_packet(struct sk_buff *skb,
+static void trace_packet(const struct sk_buff *skb,
unsigned int hook,
const struct net_device *in,
const struct net_device *out,
const char *tablename,
- struct xt_table_info *private,
- struct ip6t_entry *e)
+ const struct xt_table_info *private,
+ const struct ip6t_entry *e)
{
- void *table_base;
+ const void *table_base;
const struct ip6t_entry *root;
const char *hookname, *chainname, *comment;
unsigned int rulenum = 0;
@@ -352,9 +358,9 @@ ip6t_do_table(struct sk_buff *skb,
/* Initializing verdict to NF_DROP keeps gcc happy. */
unsigned int verdict = NF_DROP;
const char *indev, *outdev;
- void *table_base;
+ const void *table_base;
struct ip6t_entry *e, *back;
- struct xt_table_info *private;
+ const struct xt_table_info *private;
struct xt_match_param mtpar;
struct xt_target_param tgpar;

@@ -385,7 +391,7 @@ ip6t_do_table(struct sk_buff *skb,
back = get_entry(table_base, private->underflow[hook]);

do {
- struct ip6t_entry_target *t;
+ const struct ip6t_entry_target *t;

IP_NF_ASSERT(e);
IP_NF_ASSERT(back);
@@ -400,7 +406,7 @@ ip6t_do_table(struct sk_buff *skb,
ntohs(ipv6_hdr(skb)->payload_len) +
sizeof(struct ipv6hdr), 1);

- t = ip6t_get_target(e);
+ t = ip6t_get_target_c(e);
IP_NF_ASSERT(t->u.kernel.target);

#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \
@@ -482,7 +488,7 @@ ip6t_do_table(struct sk_buff *skb,
/* Figures out from what hook each rule can be called: returns 0 if
there are loops. Puts hook bitmask in comefrom. */
static int
-mark_source_chains(struct xt_table_info *newinfo,
+mark_source_chains(const struct xt_table_info *newinfo,
unsigned int valid_hooks, void *entry0)
{
unsigned int hook;
@@ -500,8 +506,8 @@ mark_source_chains(struct xt_table_info *newinfo,
e->counters.pcnt = pos;

for (;;) {
- struct ip6t_standard_target *t
- = (void *)ip6t_get_target(e);
+ const struct ip6t_standard_target *t
+ = (void *)ip6t_get_target_c(e);
int visited = e->comefrom & (1 << hook);

if (e->comefrom & (1 << NF_INET_NUMHOOKS)) {
@@ -610,9 +616,9 @@ cleanup_match(struct ip6t_entry_match *m, struct net *net, unsigned int *i)
}

static int
-check_entry(struct ip6t_entry *e, const char *name)
+check_entry(const struct ip6t_entry *e, const char *name)
{
- struct ip6t_entry_target *t;
+ const struct ip6t_entry_target *t;

if (!ip6_checkentry(&e->ipv6)) {
duprintf("ip_tables: ip check failed %p %s.\n", e, name);
@@ -623,7 +629,7 @@ check_entry(struct ip6t_entry *e, const char *name)
e->next_offset)
return -EINVAL;

- t = ip6t_get_target(e);
+ t = ip6t_get_target_c(e);
if (e->target_offset + t->u.target_size > e->next_offset)
return -EINVAL;

@@ -750,14 +756,14 @@ find_check_entry(struct ip6t_entry *e, struct net *net, const char *name,
return ret;
}

-static bool check_underflow(struct ip6t_entry *e)
+static bool check_underflow(const struct ip6t_entry *e)
{
const struct ip6t_entry_target *t;
unsigned int verdict;

if (!unconditional(&e->ipv6))
return false;
- t = ip6t_get_target(e);
+ t = ip6t_get_target_c(e);
if (strcmp(t->u.user.name, XT_STANDARD_TARGET) != 0)
return false;
verdict = ((struct ip6t_standard_target *)t)->verdict;
@@ -768,8 +774,8 @@ static bool check_underflow(struct ip6t_entry *e)
static int
check_entry_size_and_hooks(struct ip6t_entry *e,
struct xt_table_info *newinfo,
- unsigned char *base,
- unsigned char *limit,
+ const unsigned char *base,
+ const unsigned char *limit,
const unsigned int *hook_entries,
const unsigned int *underflows,
unsigned int valid_hooks,
@@ -984,11 +990,11 @@ get_counters(const struct xt_table_info *t,
local_bh_enable();
}

-static struct xt_counters *alloc_counters(struct xt_table *table)
+static struct xt_counters *alloc_counters(const struct xt_table *table)
{
unsigned int countersize;
struct xt_counters *counters;
- struct xt_table_info *private = table->private;
+ const struct xt_table_info *private = table->private;

/* We need atomic snapshot of counters: rest doesn't change
(other than comefrom, which userspace doesn't care
@@ -1006,11 +1012,11 @@ static struct xt_counters *alloc_counters(struct xt_table *table)

static int
copy_entries_to_user(unsigned int total_size,
- struct xt_table *table,
+ const struct xt_table *table,
void __user *userptr)
{
unsigned int off, num;
- struct ip6t_entry *e;
+ const struct ip6t_entry *e;
struct xt_counters *counters;
const struct xt_table_info *private = table->private;
int ret = 0;
@@ -1062,7 +1068,7 @@ copy_entries_to_user(unsigned int total_size,
}
}

- t = ip6t_get_target(e);
+ t = ip6t_get_target_c(e);
if (copy_to_user(userptr + off + e->target_offset
+ offsetof(struct ip6t_entry_target,
u.user.name),
@@ -1098,24 +1104,24 @@ static int compat_standard_to_user(void __user *dst, const void *src)
}

static inline int
-compat_calc_match(struct ip6t_entry_match *m, int *size)
+compat_calc_match(const struct ip6t_entry_match *m, int *size)
{
*size += xt_compat_match_offset(m->u.kernel.match);
return 0;
}

-static int compat_calc_entry(struct ip6t_entry *e,
+static int compat_calc_entry(const struct ip6t_entry *e,
const struct xt_table_info *info,
- void *base, struct xt_table_info *newinfo)
+ const void *base, struct xt_table_info *newinfo)
{
- struct ip6t_entry_target *t;
+ const struct ip6t_entry_target *t;
unsigned int entry_offset;
int off, i, ret;

off = sizeof(struct ip6t_entry) - sizeof(struct compat_ip6t_entry);
entry_offset = (void *)e - base;
IP6T_MATCH_ITERATE(e, compat_calc_match, &off);
- t = ip6t_get_target(e);
+ t = ip6t_get_target_c(e);
off += xt_compat_target_offset(t->u.kernel.target);
newinfo->size -= off;
ret = xt_compat_add_offset(AF_INET6, entry_offset, off);
@@ -1151,7 +1157,8 @@ static int compat_table_info(const struct xt_table_info *info,
}
#endif

-static int get_info(struct net *net, void __user *user, int *len, int compat)
+static int get_info(struct net *net, void __user *user,
+ const int *len, int compat)
{
char name[IP6T_TABLE_MAXNAMELEN];
struct xt_table *t;
@@ -1211,7 +1218,8 @@ static int get_info(struct net *net, void __user *user, int *len, int compat)
}

static int
-get_entries(struct net *net, struct ip6t_get_entries __user *uptr, int *len)
+get_entries(struct net *net, struct ip6t_get_entries __user *uptr,
+ const int *len)
{
int ret;
struct ip6t_get_entries get;
@@ -1322,7 +1330,7 @@ __do_replace(struct net *net, const char *name, unsigned int valid_hooks,
}

static int
-do_replace(struct net *net, void __user *user, unsigned int len)
+do_replace(struct net *net, const void __user *user, unsigned int len)
{
int ret;
struct ip6t_replace tmp;
@@ -1383,7 +1391,7 @@ add_counter_to_entry(struct ip6t_entry *e,
}

static int
-do_add_counters(struct net *net, void __user *user, unsigned int len,
+do_add_counters(struct net *net, const void __user *user, unsigned int len,
int compat)
{
unsigned int i, curcpu;
@@ -1582,10 +1590,10 @@ static int
check_compat_entry_size_and_hooks(struct compat_ip6t_entry *e,
struct xt_table_info *newinfo,
unsigned int *size,
- unsigned char *base,
- unsigned char *limit,
- unsigned int *hook_entries,
- unsigned int *underflows,
+ const unsigned char *base,
+ const unsigned char *limit,
+ const unsigned int *hook_entries,
+ const unsigned int *underflows,
unsigned int *i,
const char *name)
{