[NETFILTER]: x_tables: simplify compat API

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / net / ipv4 / netfilter / ip_tables.c

diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c
index 673581db986ebfcf46fbc7f3ee9ec9799141a4b5..800067d69a9ac8a421184a6f9c0abaf6d5453013 100644 (file)
--- a/net/ipv4/netfilter/ip_tables.c
+++ b/net/ipv4/netfilter/ip_tables.c
@@ -942,73 +942,28 @@ static short compat_calc_jump(u_int16_t offset)
        return delta;
 }
 
-struct compat_ipt_standard_target
+static void compat_standard_from_user(void *dst, void *src)
 {
-       struct compat_xt_entry_target target;
-       compat_int_t verdict;
-};
-
-struct compat_ipt_standard
-{
-       struct compat_ipt_entry entry;
-       struct compat_ipt_standard_target target;
-};
+       int v = *(compat_int_t *)src;
 
-#define IPT_ST_LEN             XT_ALIGN(sizeof(struct ipt_standard_target))
-#define IPT_ST_COMPAT_LEN      COMPAT_XT_ALIGN(sizeof(struct compat_ipt_standard_target))
-#define IPT_ST_OFFSET          (IPT_ST_LEN - IPT_ST_COMPAT_LEN)
+       if (v > 0)
+               v += compat_calc_jump(v);
+       memcpy(dst, &v, sizeof(v));
+}
 
-static int compat_ipt_standard_fn(void *target,
-               void **dstptr, int *size, int convert)
+static int compat_standard_to_user(void __user *dst, void *src)
 {
-       struct compat_ipt_standard_target compat_st, *pcompat_st;
-       struct ipt_standard_target st, *pst;
-       int ret;
+       compat_int_t cv = *(int *)src;
 
-       ret = 0;
-       switch (convert) {
-               case COMPAT_TO_USER:
-                       pst = target;
-                       memcpy(&compat_st.target, &pst->target,
-                               sizeof(compat_st.target));
-                       compat_st.verdict = pst->verdict;
-                       if (compat_st.verdict > 0)
-                               compat_st.verdict -=
-                                       compat_calc_jump(compat_st.verdict);
-                       compat_st.target.u.user.target_size = IPT_ST_COMPAT_LEN;
-                       if (copy_to_user(*dstptr, &compat_st, IPT_ST_COMPAT_LEN))
-                               ret = -EFAULT;
-                       *size -= IPT_ST_OFFSET;
-                       *dstptr += IPT_ST_COMPAT_LEN;
-                       break;
-               case COMPAT_FROM_USER:
-                       pcompat_st = target;
-                       memcpy(&st.target, &pcompat_st->target, IPT_ST_COMPAT_LEN);
-                       st.verdict = pcompat_st->verdict;
-                       if (st.verdict > 0)
-                               st.verdict += compat_calc_jump(st.verdict);
-                       st.target.u.user.target_size = IPT_ST_LEN;
-                       memcpy(*dstptr, &st, IPT_ST_LEN);
-                       *size += IPT_ST_OFFSET;
-                       *dstptr += IPT_ST_LEN;
-                       break;
-               case COMPAT_CALC_SIZE:
-                       *size += IPT_ST_OFFSET;
-                       break;
-               default:
-                       ret = -ENOPROTOOPT;
-                       break;
-       }
-       return ret;
+       if (cv > 0)
+               cv -= compat_calc_jump(cv);
+       return copy_to_user(dst, &cv, sizeof(cv)) ? -EFAULT : 0;
 }
 
 static inline int
 compat_calc_match(struct ipt_entry_match *m, int * size)
 {
-       if (m->u.kernel.match->compat)
-               m->u.kernel.match->compat(m, NULL, size, COMPAT_CALC_SIZE);
-       else
-               xt_compat_match(m, NULL, size, COMPAT_CALC_SIZE);
+       *size += xt_compat_match_offset(m->u.kernel.match);
        return 0;
 }
 
@@ -1023,10 +978,7 @@ static int compat_calc_entry(struct ipt_entry *e, struct xt_table_info *info,
        entry_offset = (void *)e - base;
        IPT_MATCH_ITERATE(e, compat_calc_match, &off);
        t = ipt_get_target(e);
-       if (t->u.kernel.target->compat)
-               t->u.kernel.target->compat(t, NULL, &off, COMPAT_CALC_SIZE);
-       else
-               xt_compat_target(t, NULL, &off, COMPAT_CALC_SIZE);
+       off += xt_compat_target_offset(t->u.kernel.target);
        newinfo->size -= off;
        ret = compat_add_offset(entry_offset, off);
        if (ret)
@@ -1412,17 +1364,13 @@ struct compat_ipt_replace {
 };
 
 static inline int compat_copy_match_to_user(struct ipt_entry_match *m,
-               void __user **dstptr, compat_uint_t *size)
+               void * __user *dstptr, compat_uint_t *size)
 {
-       if (m->u.kernel.match->compat)
-               return m->u.kernel.match->compat(m, dstptr, size,
-                               COMPAT_TO_USER);
-       else
-               return xt_compat_match(m, dstptr, size, COMPAT_TO_USER);
+       return xt_compat_match_to_user(m, dstptr, size);
 }
 
 static int compat_copy_entry_to_user(struct ipt_entry *e,
-               void __user **dstptr, compat_uint_t *size)
+               void * __user *dstptr, compat_uint_t *size)
 {
        struct ipt_entry_target __user *t;
        struct compat_ipt_entry __user *ce;
@@ -1442,11 +1390,7 @@ static int compat_copy_entry_to_user(struct ipt_entry *e,
        if (ret)
                goto out;
        t = ipt_get_target(e);
-       if (t->u.kernel.target->compat)
-               ret = t->u.kernel.target->compat(t, dstptr, size,
-                               COMPAT_TO_USER);
-       else
-               ret = xt_compat_target(t, dstptr, size, COMPAT_TO_USER);
+       ret = xt_compat_target_to_user(t, dstptr, size);
        if (ret)
                goto out;
        ret = -EFAULT;
@@ -1478,11 +1422,7 @@ compat_check_calc_match(struct ipt_entry_match *m,
                return match ? PTR_ERR(match) : -ENOENT;
        }
        m->u.kernel.match = match;
-
-       if (m->u.kernel.match->compat)
-               m->u.kernel.match->compat(m, NULL, size, COMPAT_CALC_SIZE);
-       else
-               xt_compat_match(m, NULL, size, COMPAT_CALC_SIZE);
+       *size += xt_compat_match_offset(match);
 
        (*i)++;
        return 0;
@@ -1543,10 +1483,7 @@ check_compat_entry_size_and_hooks(struct ipt_entry *e,
        }
        t->u.kernel.target = target;
 
-       if (t->u.kernel.target->compat)
-               t->u.kernel.target->compat(t, NULL, &off, COMPAT_CALC_SIZE);
-       else
-               xt_compat_target(t, NULL, &off, COMPAT_CALC_SIZE);
+       off += xt_compat_target_offset(target);
        *size += off;
        ret = compat_add_offset(entry_offset, off);
        if (ret)
@@ -1584,10 +1521,7 @@ static inline int compat_copy_match_from_user(struct ipt_entry_match *m,
 
        dm = (struct ipt_entry_match *)*dstptr;
        match = m->u.kernel.match;
-       if (match->compat)
-               match->compat(m, dstptr, size, COMPAT_FROM_USER);
-       else
-               xt_compat_match(m, dstptr, size, COMPAT_FROM_USER);
+       xt_compat_match_from_user(m, dstptr, size);
 
        ret = xt_check_match(match, AF_INET, dm->u.match_size - sizeof(*dm),
                             name, hookmask, ip->proto,
@@ -1635,10 +1569,7 @@ static int compat_copy_entry_from_user(struct ipt_entry *e, void **dstptr,
        de->target_offset = e->target_offset - (origsize - *size);
        t = ipt_get_target(e);
        target = t->u.kernel.target;
-       if (target->compat)
-               target->compat(t, dstptr, size, COMPAT_FROM_USER);
-       else
-               xt_compat_target(t, dstptr, size, COMPAT_FROM_USER);
+       xt_compat_target_from_user(t, dstptr, size);
 
        de->next_offset = e->next_offset - (origsize - *size);
        for (h = 0; h < NF_IP_NUMHOOKS; h++) {
@@ -2205,7 +2136,9 @@ static struct ipt_target ipt_standard_target = {
        .targetsize     = sizeof(int),
        .family         = AF_INET,
 #ifdef CONFIG_COMPAT
-       .compat         = &compat_ipt_standard_fn,
+       .compatsize     = sizeof(compat_int_t),
+       .compat_from_user = compat_standard_from_user,
+       .compat_to_user = compat_standard_to_user,
 #endif
 };