+#ifdef CONFIG_COMPAT
+struct compat_delta {
+ struct compat_delta *next;
+ u_int16_t offset;
+ short delta;
+};
+
+static struct compat_delta *compat_offsets = NULL;
+
+static int compat_add_offset(u_int16_t offset, short delta)
+{
+ struct compat_delta *tmp;
+
+ tmp = kmalloc(sizeof(struct compat_delta), GFP_KERNEL);
+ if (!tmp)
+ return -ENOMEM;
+ tmp->offset = offset;
+ tmp->delta = delta;
+ if (compat_offsets) {
+ tmp->next = compat_offsets->next;
+ compat_offsets->next = tmp;
+ } else {
+ compat_offsets = tmp;
+ tmp->next = NULL;
+ }
+ return 0;
+}
+
+static void compat_flush_offsets(void)
+{
+ struct compat_delta *tmp, *next;
+
+ if (compat_offsets) {
+ for(tmp = compat_offsets; tmp; tmp = next) {
+ next = tmp->next;
+ kfree(tmp);
+ }
+ compat_offsets = NULL;
+ }
+}
+
+static short compat_calc_jump(u_int16_t offset)
+{
+ struct compat_delta *tmp;
+ short delta;
+
+ for(tmp = compat_offsets, delta = 0; tmp; tmp = tmp->next)
+ if (tmp->offset < offset)
+ delta += tmp->delta;
+ return delta;
+}
+
+struct compat_ipt_standard_target
+{
+ 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;
+};
+
+#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)
+
+static int compat_ipt_standard_fn(void *target,
+ void **dstptr, int *size, int convert)
+{
+ struct compat_ipt_standard_target compat_st, *pcompat_st;
+ struct ipt_standard_target st, *pst;
+ int ret;
+
+ 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;
+}
+
+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);
+ return 0;
+}
+
+static int compat_calc_entry(struct ipt_entry *e, struct xt_table_info *info,
+ void *base, struct xt_table_info *newinfo)
+{
+ struct ipt_entry_target *t;
+ u_int16_t entry_offset;
+ int off, i, ret;
+
+ off = 0;
+ 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);
+ newinfo->size -= off;
+ ret = compat_add_offset(entry_offset, off);
+ if (ret)
+ return ret;
+
+ for (i = 0; i< NF_IP_NUMHOOKS; i++) {
+ if (info->hook_entry[i] && (e < (struct ipt_entry *)
+ (base + info->hook_entry[i])))
+ newinfo->hook_entry[i] -= off;
+ if (info->underflow[i] && (e < (struct ipt_entry *)
+ (base + info->underflow[i])))
+ newinfo->underflow[i] -= off;
+ }
+ return 0;
+}
+
+static int compat_table_info(struct xt_table_info *info,
+ struct xt_table_info *newinfo)
+{
+ void *loc_cpu_entry;
+ int i;
+
+ if (!newinfo || !info)
+ return -EINVAL;
+
+ memset(newinfo, 0, sizeof(struct xt_table_info));
+ newinfo->size = info->size;
+ newinfo->number = info->number;
+ for (i = 0; i < NF_IP_NUMHOOKS; i++) {
+ newinfo->hook_entry[i] = info->hook_entry[i];
+ newinfo->underflow[i] = info->underflow[i];
+ }
+ loc_cpu_entry = info->entries[raw_smp_processor_id()];
+ return IPT_ENTRY_ITERATE(loc_cpu_entry, info->size,
+ compat_calc_entry, info, loc_cpu_entry, newinfo);
+}
+#endif
+
+static int get_info(void __user *user, int *len, int compat)
+{
+ char name[IPT_TABLE_MAXNAMELEN];
+ struct ipt_table *t;
+ int ret;
+
+ if (*len != sizeof(struct ipt_getinfo)) {
+ duprintf("length %u != %u\n", *len,
+ (unsigned int)sizeof(struct ipt_getinfo));
+ return -EINVAL;
+ }
+
+ if (copy_from_user(name, user, sizeof(name)) != 0)
+ return -EFAULT;
+
+ name[IPT_TABLE_MAXNAMELEN-1] = '\0';
+#ifdef CONFIG_COMPAT
+ if (compat)
+ xt_compat_lock(AF_INET);
+#endif
+ t = try_then_request_module(xt_find_table_lock(AF_INET, name),
+ "iptable_%s", name);
+ if (t && !IS_ERR(t)) {
+ struct ipt_getinfo info;
+ struct xt_table_info *private = t->private;
+
+#ifdef CONFIG_COMPAT
+ if (compat) {
+ struct xt_table_info tmp;
+ ret = compat_table_info(private, &tmp);
+ compat_flush_offsets();
+ private = &tmp;
+ }
+#endif
+ info.valid_hooks = t->valid_hooks;
+ memcpy(info.hook_entry, private->hook_entry,
+ sizeof(info.hook_entry));
+ memcpy(info.underflow, private->underflow,
+ sizeof(info.underflow));
+ info.num_entries = private->number;
+ info.size = private->size;
+ strcpy(info.name, name);
+
+ if (copy_to_user(user, &info, *len) != 0)
+ ret = -EFAULT;
+ else
+ ret = 0;
+
+ xt_table_unlock(t);
+ module_put(t->me);
+ } else
+ ret = t ? PTR_ERR(t) : -ENOENT;
+#ifdef CONFIG_COMPAT
+ if (compat)
+ xt_compat_unlock(AF_INET);
+#endif
+ return ret;
+}
+