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![Andy Shevchenko](/assets/img/avatar_default.png)
Use string_is_terminated() helper instead of cpecific memchr() call. This shows better the intention of the call. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Link: https://lore.kernel.org/r/20230208133153.22528-2-andriy.shevchenko@linux.intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
1815 lines
41 KiB
C
1815 lines
41 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* NETLINK Generic Netlink Family
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*
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* Authors: Jamal Hadi Salim
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* Thomas Graf <tgraf@suug.ch>
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* Johannes Berg <johannes@sipsolutions.net>
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/socket.h>
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#include <linux/string_helpers.h>
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#include <linux/skbuff.h>
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#include <linux/mutex.h>
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#include <linux/bitmap.h>
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#include <linux/rwsem.h>
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#include <linux/idr.h>
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#include <net/sock.h>
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#include <net/genetlink.h>
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static DEFINE_MUTEX(genl_mutex); /* serialization of message processing */
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static DECLARE_RWSEM(cb_lock);
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atomic_t genl_sk_destructing_cnt = ATOMIC_INIT(0);
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DECLARE_WAIT_QUEUE_HEAD(genl_sk_destructing_waitq);
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void genl_lock(void)
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{
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mutex_lock(&genl_mutex);
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}
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EXPORT_SYMBOL(genl_lock);
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void genl_unlock(void)
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{
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mutex_unlock(&genl_mutex);
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}
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EXPORT_SYMBOL(genl_unlock);
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static void genl_lock_all(void)
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{
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down_write(&cb_lock);
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genl_lock();
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}
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static void genl_unlock_all(void)
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{
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genl_unlock();
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up_write(&cb_lock);
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}
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static DEFINE_IDR(genl_fam_idr);
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/*
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* Bitmap of multicast groups that are currently in use.
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*
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* To avoid an allocation at boot of just one unsigned long,
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* declare it global instead.
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* Bit 0 is marked as already used since group 0 is invalid.
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* Bit 1 is marked as already used since the drop-monitor code
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* abuses the API and thinks it can statically use group 1.
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* That group will typically conflict with other groups that
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* any proper users use.
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* Bit 16 is marked as used since it's used for generic netlink
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* and the code no longer marks pre-reserved IDs as used.
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* Bit 17 is marked as already used since the VFS quota code
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* also abused this API and relied on family == group ID, we
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* cater to that by giving it a static family and group ID.
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* Bit 18 is marked as already used since the PMCRAID driver
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* did the same thing as the VFS quota code (maybe copied?)
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*/
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static unsigned long mc_group_start = 0x3 | BIT(GENL_ID_CTRL) |
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BIT(GENL_ID_VFS_DQUOT) |
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BIT(GENL_ID_PMCRAID);
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static unsigned long *mc_groups = &mc_group_start;
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static unsigned long mc_groups_longs = 1;
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/* We need the last attribute with non-zero ID therefore a 2-entry array */
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static struct nla_policy genl_policy_reject_all[] = {
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{ .type = NLA_REJECT },
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{ .type = NLA_REJECT },
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};
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static int genl_ctrl_event(int event, const struct genl_family *family,
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const struct genl_multicast_group *grp,
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int grp_id);
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static void
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genl_op_fill_in_reject_policy(const struct genl_family *family,
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struct genl_ops *op)
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{
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BUILD_BUG_ON(ARRAY_SIZE(genl_policy_reject_all) - 1 != 1);
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if (op->policy || op->cmd < family->resv_start_op)
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return;
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op->policy = genl_policy_reject_all;
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op->maxattr = 1;
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}
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static void
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genl_op_fill_in_reject_policy_split(const struct genl_family *family,
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struct genl_split_ops *op)
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{
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if (op->policy)
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return;
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op->policy = genl_policy_reject_all;
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op->maxattr = 1;
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}
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static const struct genl_family *genl_family_find_byid(unsigned int id)
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{
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return idr_find(&genl_fam_idr, id);
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}
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static const struct genl_family *genl_family_find_byname(char *name)
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{
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const struct genl_family *family;
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unsigned int id;
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idr_for_each_entry(&genl_fam_idr, family, id)
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if (strcmp(family->name, name) == 0)
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return family;
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return NULL;
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}
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struct genl_op_iter {
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const struct genl_family *family;
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struct genl_split_ops doit;
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struct genl_split_ops dumpit;
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int cmd_idx;
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int entry_idx;
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u32 cmd;
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u8 flags;
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};
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static void genl_op_from_full(const struct genl_family *family,
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unsigned int i, struct genl_ops *op)
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{
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*op = family->ops[i];
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if (!op->maxattr)
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op->maxattr = family->maxattr;
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if (!op->policy)
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op->policy = family->policy;
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genl_op_fill_in_reject_policy(family, op);
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}
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static int genl_get_cmd_full(u32 cmd, const struct genl_family *family,
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struct genl_ops *op)
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{
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int i;
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for (i = 0; i < family->n_ops; i++)
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if (family->ops[i].cmd == cmd) {
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genl_op_from_full(family, i, op);
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return 0;
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}
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return -ENOENT;
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}
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static void genl_op_from_small(const struct genl_family *family,
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unsigned int i, struct genl_ops *op)
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{
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memset(op, 0, sizeof(*op));
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op->doit = family->small_ops[i].doit;
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op->dumpit = family->small_ops[i].dumpit;
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op->cmd = family->small_ops[i].cmd;
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op->internal_flags = family->small_ops[i].internal_flags;
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op->flags = family->small_ops[i].flags;
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op->validate = family->small_ops[i].validate;
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op->maxattr = family->maxattr;
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op->policy = family->policy;
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genl_op_fill_in_reject_policy(family, op);
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}
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static int genl_get_cmd_small(u32 cmd, const struct genl_family *family,
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struct genl_ops *op)
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{
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int i;
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for (i = 0; i < family->n_small_ops; i++)
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if (family->small_ops[i].cmd == cmd) {
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genl_op_from_small(family, i, op);
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return 0;
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}
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return -ENOENT;
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}
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static void genl_op_from_split(struct genl_op_iter *iter)
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{
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const struct genl_family *family = iter->family;
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int i, cnt = 0;
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i = iter->entry_idx - family->n_ops - family->n_small_ops;
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if (family->split_ops[i + cnt].flags & GENL_CMD_CAP_DO) {
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iter->doit = family->split_ops[i + cnt];
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genl_op_fill_in_reject_policy_split(family, &iter->doit);
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cnt++;
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} else {
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memset(&iter->doit, 0, sizeof(iter->doit));
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}
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if (i + cnt < family->n_split_ops &&
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family->split_ops[i + cnt].flags & GENL_CMD_CAP_DUMP) {
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iter->dumpit = family->split_ops[i + cnt];
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genl_op_fill_in_reject_policy_split(family, &iter->dumpit);
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cnt++;
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} else {
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memset(&iter->dumpit, 0, sizeof(iter->dumpit));
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}
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WARN_ON(!cnt);
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iter->entry_idx += cnt;
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}
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static int
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genl_get_cmd_split(u32 cmd, u8 flag, const struct genl_family *family,
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struct genl_split_ops *op)
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{
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int i;
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for (i = 0; i < family->n_split_ops; i++)
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if (family->split_ops[i].cmd == cmd &&
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family->split_ops[i].flags & flag) {
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*op = family->split_ops[i];
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return 0;
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}
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return -ENOENT;
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}
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static int
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genl_cmd_full_to_split(struct genl_split_ops *op,
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const struct genl_family *family,
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const struct genl_ops *full, u8 flags)
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{
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if ((flags & GENL_CMD_CAP_DO && !full->doit) ||
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(flags & GENL_CMD_CAP_DUMP && !full->dumpit)) {
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memset(op, 0, sizeof(*op));
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return -ENOENT;
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}
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if (flags & GENL_CMD_CAP_DUMP) {
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op->start = full->start;
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op->dumpit = full->dumpit;
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op->done = full->done;
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} else {
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op->pre_doit = family->pre_doit;
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op->doit = full->doit;
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op->post_doit = family->post_doit;
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}
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if (flags & GENL_CMD_CAP_DUMP &&
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full->validate & GENL_DONT_VALIDATE_DUMP) {
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op->policy = NULL;
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op->maxattr = 0;
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} else {
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op->policy = full->policy;
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op->maxattr = full->maxattr;
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}
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op->cmd = full->cmd;
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op->internal_flags = full->internal_flags;
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op->flags = full->flags;
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op->validate = full->validate;
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/* Make sure flags include the GENL_CMD_CAP_DO / GENL_CMD_CAP_DUMP */
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op->flags |= flags;
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return 0;
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}
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/* Must make sure that op is initialized to 0 on failure */
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static int
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genl_get_cmd(u32 cmd, u8 flags, const struct genl_family *family,
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struct genl_split_ops *op)
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{
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struct genl_ops full;
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int err;
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err = genl_get_cmd_full(cmd, family, &full);
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if (err == -ENOENT)
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err = genl_get_cmd_small(cmd, family, &full);
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/* Found one of legacy forms */
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if (err == 0)
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return genl_cmd_full_to_split(op, family, &full, flags);
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err = genl_get_cmd_split(cmd, flags, family, op);
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if (err)
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memset(op, 0, sizeof(*op));
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return err;
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}
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/* For policy dumping only, get ops of both do and dump.
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* Fail if both are missing, genl_get_cmd() will zero-init in case of failure.
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*/
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static int
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genl_get_cmd_both(u32 cmd, const struct genl_family *family,
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struct genl_split_ops *doit, struct genl_split_ops *dumpit)
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{
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int err1, err2;
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err1 = genl_get_cmd(cmd, GENL_CMD_CAP_DO, family, doit);
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err2 = genl_get_cmd(cmd, GENL_CMD_CAP_DUMP, family, dumpit);
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return err1 && err2 ? -ENOENT : 0;
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}
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static bool
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genl_op_iter_init(const struct genl_family *family, struct genl_op_iter *iter)
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{
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iter->family = family;
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iter->cmd_idx = 0;
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iter->entry_idx = 0;
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iter->flags = 0;
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return iter->family->n_ops +
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iter->family->n_small_ops +
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iter->family->n_split_ops;
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}
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static bool genl_op_iter_next(struct genl_op_iter *iter)
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{
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const struct genl_family *family = iter->family;
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bool legacy_op = true;
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struct genl_ops op;
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if (iter->entry_idx < family->n_ops) {
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genl_op_from_full(family, iter->entry_idx, &op);
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} else if (iter->entry_idx < family->n_ops + family->n_small_ops) {
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genl_op_from_small(family, iter->entry_idx - family->n_ops,
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&op);
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} else if (iter->entry_idx <
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family->n_ops + family->n_small_ops + family->n_split_ops) {
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legacy_op = false;
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/* updates entry_idx */
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genl_op_from_split(iter);
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} else {
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return false;
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}
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iter->cmd_idx++;
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if (legacy_op) {
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iter->entry_idx++;
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genl_cmd_full_to_split(&iter->doit, family,
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&op, GENL_CMD_CAP_DO);
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genl_cmd_full_to_split(&iter->dumpit, family,
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&op, GENL_CMD_CAP_DUMP);
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}
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iter->cmd = iter->doit.cmd | iter->dumpit.cmd;
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iter->flags = iter->doit.flags | iter->dumpit.flags;
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return true;
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}
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static void
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genl_op_iter_copy(struct genl_op_iter *dst, struct genl_op_iter *src)
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{
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*dst = *src;
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}
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static unsigned int genl_op_iter_idx(struct genl_op_iter *iter)
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{
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return iter->cmd_idx;
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}
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static int genl_allocate_reserve_groups(int n_groups, int *first_id)
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{
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unsigned long *new_groups;
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int start = 0;
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int i;
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int id;
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bool fits;
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do {
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if (start == 0)
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id = find_first_zero_bit(mc_groups,
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mc_groups_longs *
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BITS_PER_LONG);
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else
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id = find_next_zero_bit(mc_groups,
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mc_groups_longs * BITS_PER_LONG,
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start);
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fits = true;
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for (i = id;
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i < min_t(int, id + n_groups,
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mc_groups_longs * BITS_PER_LONG);
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i++) {
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if (test_bit(i, mc_groups)) {
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start = i;
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fits = false;
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break;
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}
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}
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if (id + n_groups > mc_groups_longs * BITS_PER_LONG) {
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unsigned long new_longs = mc_groups_longs +
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BITS_TO_LONGS(n_groups);
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size_t nlen = new_longs * sizeof(unsigned long);
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if (mc_groups == &mc_group_start) {
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new_groups = kzalloc(nlen, GFP_KERNEL);
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if (!new_groups)
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return -ENOMEM;
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mc_groups = new_groups;
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*mc_groups = mc_group_start;
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} else {
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new_groups = krealloc(mc_groups, nlen,
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GFP_KERNEL);
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if (!new_groups)
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return -ENOMEM;
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mc_groups = new_groups;
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for (i = 0; i < BITS_TO_LONGS(n_groups); i++)
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mc_groups[mc_groups_longs + i] = 0;
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}
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mc_groups_longs = new_longs;
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}
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} while (!fits);
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for (i = id; i < id + n_groups; i++)
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set_bit(i, mc_groups);
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*first_id = id;
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return 0;
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}
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static struct genl_family genl_ctrl;
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static int genl_validate_assign_mc_groups(struct genl_family *family)
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{
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int first_id;
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int n_groups = family->n_mcgrps;
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int err = 0, i;
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bool groups_allocated = false;
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if (!n_groups)
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return 0;
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for (i = 0; i < n_groups; i++) {
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const struct genl_multicast_group *grp = &family->mcgrps[i];
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if (WARN_ON(grp->name[0] == '\0'))
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return -EINVAL;
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if (WARN_ON(!string_is_terminated(grp->name, GENL_NAMSIZ)))
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return -EINVAL;
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}
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/* special-case our own group and hacks */
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if (family == &genl_ctrl) {
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first_id = GENL_ID_CTRL;
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BUG_ON(n_groups != 1);
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} else if (strcmp(family->name, "NET_DM") == 0) {
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first_id = 1;
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BUG_ON(n_groups != 1);
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} else if (family->id == GENL_ID_VFS_DQUOT) {
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first_id = GENL_ID_VFS_DQUOT;
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BUG_ON(n_groups != 1);
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} else if (family->id == GENL_ID_PMCRAID) {
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first_id = GENL_ID_PMCRAID;
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BUG_ON(n_groups != 1);
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} else {
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groups_allocated = true;
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err = genl_allocate_reserve_groups(n_groups, &first_id);
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if (err)
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return err;
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}
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family->mcgrp_offset = first_id;
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/* if still initializing, can't and don't need to realloc bitmaps */
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if (!init_net.genl_sock)
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return 0;
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if (family->netnsok) {
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struct net *net;
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netlink_table_grab();
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rcu_read_lock();
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for_each_net_rcu(net) {
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err = __netlink_change_ngroups(net->genl_sock,
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mc_groups_longs * BITS_PER_LONG);
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if (err) {
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/*
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* No need to roll back, can only fail if
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* memory allocation fails and then the
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* number of _possible_ groups has been
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* increased on some sockets which is ok.
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*/
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break;
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}
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}
|
|
rcu_read_unlock();
|
|
netlink_table_ungrab();
|
|
} else {
|
|
err = netlink_change_ngroups(init_net.genl_sock,
|
|
mc_groups_longs * BITS_PER_LONG);
|
|
}
|
|
|
|
if (groups_allocated && err) {
|
|
for (i = 0; i < family->n_mcgrps; i++)
|
|
clear_bit(family->mcgrp_offset + i, mc_groups);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static void genl_unregister_mc_groups(const struct genl_family *family)
|
|
{
|
|
struct net *net;
|
|
int i;
|
|
|
|
netlink_table_grab();
|
|
rcu_read_lock();
|
|
for_each_net_rcu(net) {
|
|
for (i = 0; i < family->n_mcgrps; i++)
|
|
__netlink_clear_multicast_users(
|
|
net->genl_sock, family->mcgrp_offset + i);
|
|
}
|
|
rcu_read_unlock();
|
|
netlink_table_ungrab();
|
|
|
|
for (i = 0; i < family->n_mcgrps; i++) {
|
|
int grp_id = family->mcgrp_offset + i;
|
|
|
|
if (grp_id != 1)
|
|
clear_bit(grp_id, mc_groups);
|
|
genl_ctrl_event(CTRL_CMD_DELMCAST_GRP, family,
|
|
&family->mcgrps[i], grp_id);
|
|
}
|
|
}
|
|
|
|
static bool genl_split_op_check(const struct genl_split_ops *op)
|
|
{
|
|
if (WARN_ON(hweight8(op->flags & (GENL_CMD_CAP_DO |
|
|
GENL_CMD_CAP_DUMP)) != 1))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
static int genl_validate_ops(const struct genl_family *family)
|
|
{
|
|
struct genl_op_iter i, j;
|
|
unsigned int s;
|
|
|
|
if (WARN_ON(family->n_ops && !family->ops) ||
|
|
WARN_ON(family->n_small_ops && !family->small_ops) ||
|
|
WARN_ON(family->n_split_ops && !family->split_ops))
|
|
return -EINVAL;
|
|
|
|
for (genl_op_iter_init(family, &i); genl_op_iter_next(&i); ) {
|
|
if (!(i.flags & (GENL_CMD_CAP_DO | GENL_CMD_CAP_DUMP)))
|
|
return -EINVAL;
|
|
|
|
if (WARN_ON(i.cmd >= family->resv_start_op &&
|
|
(i.doit.validate || i.dumpit.validate)))
|
|
return -EINVAL;
|
|
|
|
genl_op_iter_copy(&j, &i);
|
|
while (genl_op_iter_next(&j)) {
|
|
if (i.cmd == j.cmd)
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
if (family->n_split_ops) {
|
|
if (genl_split_op_check(&family->split_ops[0]))
|
|
return -EINVAL;
|
|
}
|
|
|
|
for (s = 1; s < family->n_split_ops; s++) {
|
|
const struct genl_split_ops *a, *b;
|
|
|
|
a = &family->split_ops[s - 1];
|
|
b = &family->split_ops[s];
|
|
|
|
if (genl_split_op_check(b))
|
|
return -EINVAL;
|
|
|
|
/* Check sort order */
|
|
if (a->cmd < b->cmd)
|
|
continue;
|
|
|
|
if (a->internal_flags != b->internal_flags ||
|
|
((a->flags ^ b->flags) & ~(GENL_CMD_CAP_DO |
|
|
GENL_CMD_CAP_DUMP))) {
|
|
WARN_ON(1);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if ((a->flags & GENL_CMD_CAP_DO) &&
|
|
(b->flags & GENL_CMD_CAP_DUMP))
|
|
continue;
|
|
|
|
WARN_ON(1);
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* genl_register_family - register a generic netlink family
|
|
* @family: generic netlink family
|
|
*
|
|
* Registers the specified family after validating it first. Only one
|
|
* family may be registered with the same family name or identifier.
|
|
*
|
|
* The family's ops, multicast groups and module pointer must already
|
|
* be assigned.
|
|
*
|
|
* Return 0 on success or a negative error code.
|
|
*/
|
|
int genl_register_family(struct genl_family *family)
|
|
{
|
|
int err, i;
|
|
int start = GENL_START_ALLOC, end = GENL_MAX_ID;
|
|
|
|
err = genl_validate_ops(family);
|
|
if (err)
|
|
return err;
|
|
|
|
genl_lock_all();
|
|
|
|
if (genl_family_find_byname(family->name)) {
|
|
err = -EEXIST;
|
|
goto errout_locked;
|
|
}
|
|
|
|
/*
|
|
* Sadly, a few cases need to be special-cased
|
|
* due to them having previously abused the API
|
|
* and having used their family ID also as their
|
|
* multicast group ID, so we use reserved IDs
|
|
* for both to be sure we can do that mapping.
|
|
*/
|
|
if (family == &genl_ctrl) {
|
|
/* and this needs to be special for initial family lookups */
|
|
start = end = GENL_ID_CTRL;
|
|
} else if (strcmp(family->name, "pmcraid") == 0) {
|
|
start = end = GENL_ID_PMCRAID;
|
|
} else if (strcmp(family->name, "VFS_DQUOT") == 0) {
|
|
start = end = GENL_ID_VFS_DQUOT;
|
|
}
|
|
|
|
family->id = idr_alloc_cyclic(&genl_fam_idr, family,
|
|
start, end + 1, GFP_KERNEL);
|
|
if (family->id < 0) {
|
|
err = family->id;
|
|
goto errout_locked;
|
|
}
|
|
|
|
err = genl_validate_assign_mc_groups(family);
|
|
if (err)
|
|
goto errout_remove;
|
|
|
|
genl_unlock_all();
|
|
|
|
/* send all events */
|
|
genl_ctrl_event(CTRL_CMD_NEWFAMILY, family, NULL, 0);
|
|
for (i = 0; i < family->n_mcgrps; i++)
|
|
genl_ctrl_event(CTRL_CMD_NEWMCAST_GRP, family,
|
|
&family->mcgrps[i], family->mcgrp_offset + i);
|
|
|
|
return 0;
|
|
|
|
errout_remove:
|
|
idr_remove(&genl_fam_idr, family->id);
|
|
errout_locked:
|
|
genl_unlock_all();
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL(genl_register_family);
|
|
|
|
/**
|
|
* genl_unregister_family - unregister generic netlink family
|
|
* @family: generic netlink family
|
|
*
|
|
* Unregisters the specified family.
|
|
*
|
|
* Returns 0 on success or a negative error code.
|
|
*/
|
|
int genl_unregister_family(const struct genl_family *family)
|
|
{
|
|
genl_lock_all();
|
|
|
|
if (!genl_family_find_byid(family->id)) {
|
|
genl_unlock_all();
|
|
return -ENOENT;
|
|
}
|
|
|
|
genl_unregister_mc_groups(family);
|
|
|
|
idr_remove(&genl_fam_idr, family->id);
|
|
|
|
up_write(&cb_lock);
|
|
wait_event(genl_sk_destructing_waitq,
|
|
atomic_read(&genl_sk_destructing_cnt) == 0);
|
|
genl_unlock();
|
|
|
|
genl_ctrl_event(CTRL_CMD_DELFAMILY, family, NULL, 0);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(genl_unregister_family);
|
|
|
|
/**
|
|
* genlmsg_put - Add generic netlink header to netlink message
|
|
* @skb: socket buffer holding the message
|
|
* @portid: netlink portid the message is addressed to
|
|
* @seq: sequence number (usually the one of the sender)
|
|
* @family: generic netlink family
|
|
* @flags: netlink message flags
|
|
* @cmd: generic netlink command
|
|
*
|
|
* Returns pointer to user specific header
|
|
*/
|
|
void *genlmsg_put(struct sk_buff *skb, u32 portid, u32 seq,
|
|
const struct genl_family *family, int flags, u8 cmd)
|
|
{
|
|
struct nlmsghdr *nlh;
|
|
struct genlmsghdr *hdr;
|
|
|
|
nlh = nlmsg_put(skb, portid, seq, family->id, GENL_HDRLEN +
|
|
family->hdrsize, flags);
|
|
if (nlh == NULL)
|
|
return NULL;
|
|
|
|
hdr = nlmsg_data(nlh);
|
|
hdr->cmd = cmd;
|
|
hdr->version = family->version;
|
|
hdr->reserved = 0;
|
|
|
|
return (char *) hdr + GENL_HDRLEN;
|
|
}
|
|
EXPORT_SYMBOL(genlmsg_put);
|
|
|
|
static struct genl_dumpit_info *genl_dumpit_info_alloc(void)
|
|
{
|
|
return kmalloc(sizeof(struct genl_dumpit_info), GFP_KERNEL);
|
|
}
|
|
|
|
static void genl_dumpit_info_free(const struct genl_dumpit_info *info)
|
|
{
|
|
kfree(info);
|
|
}
|
|
|
|
static struct nlattr **
|
|
genl_family_rcv_msg_attrs_parse(const struct genl_family *family,
|
|
struct nlmsghdr *nlh,
|
|
struct netlink_ext_ack *extack,
|
|
const struct genl_split_ops *ops,
|
|
int hdrlen,
|
|
enum genl_validate_flags no_strict_flag)
|
|
{
|
|
enum netlink_validation validate = ops->validate & no_strict_flag ?
|
|
NL_VALIDATE_LIBERAL :
|
|
NL_VALIDATE_STRICT;
|
|
struct nlattr **attrbuf;
|
|
int err;
|
|
|
|
if (!ops->maxattr)
|
|
return NULL;
|
|
|
|
attrbuf = kmalloc_array(ops->maxattr + 1,
|
|
sizeof(struct nlattr *), GFP_KERNEL);
|
|
if (!attrbuf)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
err = __nlmsg_parse(nlh, hdrlen, attrbuf, ops->maxattr, ops->policy,
|
|
validate, extack);
|
|
if (err) {
|
|
kfree(attrbuf);
|
|
return ERR_PTR(err);
|
|
}
|
|
return attrbuf;
|
|
}
|
|
|
|
static void genl_family_rcv_msg_attrs_free(struct nlattr **attrbuf)
|
|
{
|
|
kfree(attrbuf);
|
|
}
|
|
|
|
struct genl_start_context {
|
|
const struct genl_family *family;
|
|
struct nlmsghdr *nlh;
|
|
struct netlink_ext_ack *extack;
|
|
const struct genl_split_ops *ops;
|
|
int hdrlen;
|
|
};
|
|
|
|
static int genl_start(struct netlink_callback *cb)
|
|
{
|
|
struct genl_start_context *ctx = cb->data;
|
|
const struct genl_split_ops *ops;
|
|
struct genl_dumpit_info *info;
|
|
struct nlattr **attrs = NULL;
|
|
int rc = 0;
|
|
|
|
ops = ctx->ops;
|
|
if (!(ops->validate & GENL_DONT_VALIDATE_DUMP) &&
|
|
ctx->nlh->nlmsg_len < nlmsg_msg_size(ctx->hdrlen))
|
|
return -EINVAL;
|
|
|
|
attrs = genl_family_rcv_msg_attrs_parse(ctx->family, ctx->nlh, ctx->extack,
|
|
ops, ctx->hdrlen,
|
|
GENL_DONT_VALIDATE_DUMP_STRICT);
|
|
if (IS_ERR(attrs))
|
|
return PTR_ERR(attrs);
|
|
|
|
info = genl_dumpit_info_alloc();
|
|
if (!info) {
|
|
genl_family_rcv_msg_attrs_free(attrs);
|
|
return -ENOMEM;
|
|
}
|
|
info->family = ctx->family;
|
|
info->op = *ops;
|
|
info->attrs = attrs;
|
|
|
|
cb->data = info;
|
|
if (ops->start) {
|
|
if (!ctx->family->parallel_ops)
|
|
genl_lock();
|
|
rc = ops->start(cb);
|
|
if (!ctx->family->parallel_ops)
|
|
genl_unlock();
|
|
}
|
|
|
|
if (rc) {
|
|
genl_family_rcv_msg_attrs_free(info->attrs);
|
|
genl_dumpit_info_free(info);
|
|
cb->data = NULL;
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static int genl_lock_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
|
|
{
|
|
const struct genl_split_ops *ops = &genl_dumpit_info(cb)->op;
|
|
int rc;
|
|
|
|
genl_lock();
|
|
rc = ops->dumpit(skb, cb);
|
|
genl_unlock();
|
|
return rc;
|
|
}
|
|
|
|
static int genl_lock_done(struct netlink_callback *cb)
|
|
{
|
|
const struct genl_dumpit_info *info = genl_dumpit_info(cb);
|
|
const struct genl_split_ops *ops = &info->op;
|
|
int rc = 0;
|
|
|
|
if (ops->done) {
|
|
genl_lock();
|
|
rc = ops->done(cb);
|
|
genl_unlock();
|
|
}
|
|
genl_family_rcv_msg_attrs_free(info->attrs);
|
|
genl_dumpit_info_free(info);
|
|
return rc;
|
|
}
|
|
|
|
static int genl_parallel_done(struct netlink_callback *cb)
|
|
{
|
|
const struct genl_dumpit_info *info = genl_dumpit_info(cb);
|
|
const struct genl_split_ops *ops = &info->op;
|
|
int rc = 0;
|
|
|
|
if (ops->done)
|
|
rc = ops->done(cb);
|
|
genl_family_rcv_msg_attrs_free(info->attrs);
|
|
genl_dumpit_info_free(info);
|
|
return rc;
|
|
}
|
|
|
|
static int genl_family_rcv_msg_dumpit(const struct genl_family *family,
|
|
struct sk_buff *skb,
|
|
struct nlmsghdr *nlh,
|
|
struct netlink_ext_ack *extack,
|
|
const struct genl_split_ops *ops,
|
|
int hdrlen, struct net *net)
|
|
{
|
|
struct genl_start_context ctx;
|
|
int err;
|
|
|
|
ctx.family = family;
|
|
ctx.nlh = nlh;
|
|
ctx.extack = extack;
|
|
ctx.ops = ops;
|
|
ctx.hdrlen = hdrlen;
|
|
|
|
if (!family->parallel_ops) {
|
|
struct netlink_dump_control c = {
|
|
.module = family->module,
|
|
.data = &ctx,
|
|
.start = genl_start,
|
|
.dump = genl_lock_dumpit,
|
|
.done = genl_lock_done,
|
|
};
|
|
|
|
genl_unlock();
|
|
err = __netlink_dump_start(net->genl_sock, skb, nlh, &c);
|
|
genl_lock();
|
|
} else {
|
|
struct netlink_dump_control c = {
|
|
.module = family->module,
|
|
.data = &ctx,
|
|
.start = genl_start,
|
|
.dump = ops->dumpit,
|
|
.done = genl_parallel_done,
|
|
};
|
|
|
|
err = __netlink_dump_start(net->genl_sock, skb, nlh, &c);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int genl_family_rcv_msg_doit(const struct genl_family *family,
|
|
struct sk_buff *skb,
|
|
struct nlmsghdr *nlh,
|
|
struct netlink_ext_ack *extack,
|
|
const struct genl_split_ops *ops,
|
|
int hdrlen, struct net *net)
|
|
{
|
|
struct nlattr **attrbuf;
|
|
struct genl_info info;
|
|
int err;
|
|
|
|
attrbuf = genl_family_rcv_msg_attrs_parse(family, nlh, extack,
|
|
ops, hdrlen,
|
|
GENL_DONT_VALIDATE_STRICT);
|
|
if (IS_ERR(attrbuf))
|
|
return PTR_ERR(attrbuf);
|
|
|
|
info.snd_seq = nlh->nlmsg_seq;
|
|
info.snd_portid = NETLINK_CB(skb).portid;
|
|
info.nlhdr = nlh;
|
|
info.genlhdr = nlmsg_data(nlh);
|
|
info.userhdr = nlmsg_data(nlh) + GENL_HDRLEN;
|
|
info.attrs = attrbuf;
|
|
info.extack = extack;
|
|
genl_info_net_set(&info, net);
|
|
memset(&info.user_ptr, 0, sizeof(info.user_ptr));
|
|
|
|
if (ops->pre_doit) {
|
|
err = ops->pre_doit(ops, skb, &info);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
|
|
err = ops->doit(skb, &info);
|
|
|
|
if (ops->post_doit)
|
|
ops->post_doit(ops, skb, &info);
|
|
|
|
out:
|
|
genl_family_rcv_msg_attrs_free(attrbuf);
|
|
|
|
return err;
|
|
}
|
|
|
|
static int genl_header_check(const struct genl_family *family,
|
|
struct nlmsghdr *nlh, struct genlmsghdr *hdr,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
u16 flags;
|
|
|
|
/* Only for commands added after we started validating */
|
|
if (hdr->cmd < family->resv_start_op)
|
|
return 0;
|
|
|
|
if (hdr->reserved) {
|
|
NL_SET_ERR_MSG(extack, "genlmsghdr.reserved field is not 0");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Old netlink flags have pretty loose semantics, allow only the flags
|
|
* consumed by the core where we can enforce the meaning.
|
|
*/
|
|
flags = nlh->nlmsg_flags;
|
|
if ((flags & NLM_F_DUMP) == NLM_F_DUMP) /* DUMP is 2 bits */
|
|
flags &= ~NLM_F_DUMP;
|
|
if (flags & ~(NLM_F_REQUEST | NLM_F_ACK | NLM_F_ECHO)) {
|
|
NL_SET_ERR_MSG(extack,
|
|
"ambiguous or reserved bits set in nlmsg_flags");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int genl_family_rcv_msg(const struct genl_family *family,
|
|
struct sk_buff *skb,
|
|
struct nlmsghdr *nlh,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
struct net *net = sock_net(skb->sk);
|
|
struct genlmsghdr *hdr = nlmsg_data(nlh);
|
|
struct genl_split_ops op;
|
|
int hdrlen;
|
|
u8 flags;
|
|
|
|
/* this family doesn't exist in this netns */
|
|
if (!family->netnsok && !net_eq(net, &init_net))
|
|
return -ENOENT;
|
|
|
|
hdrlen = GENL_HDRLEN + family->hdrsize;
|
|
if (nlh->nlmsg_len < nlmsg_msg_size(hdrlen))
|
|
return -EINVAL;
|
|
|
|
if (genl_header_check(family, nlh, hdr, extack))
|
|
return -EINVAL;
|
|
|
|
flags = (nlh->nlmsg_flags & NLM_F_DUMP) == NLM_F_DUMP ?
|
|
GENL_CMD_CAP_DUMP : GENL_CMD_CAP_DO;
|
|
if (genl_get_cmd(hdr->cmd, flags, family, &op))
|
|
return -EOPNOTSUPP;
|
|
|
|
if ((op.flags & GENL_ADMIN_PERM) &&
|
|
!netlink_capable(skb, CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
|
|
if ((op.flags & GENL_UNS_ADMIN_PERM) &&
|
|
!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
|
|
if (flags & GENL_CMD_CAP_DUMP)
|
|
return genl_family_rcv_msg_dumpit(family, skb, nlh, extack,
|
|
&op, hdrlen, net);
|
|
else
|
|
return genl_family_rcv_msg_doit(family, skb, nlh, extack,
|
|
&op, hdrlen, net);
|
|
}
|
|
|
|
static int genl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
const struct genl_family *family;
|
|
int err;
|
|
|
|
family = genl_family_find_byid(nlh->nlmsg_type);
|
|
if (family == NULL)
|
|
return -ENOENT;
|
|
|
|
if (!family->parallel_ops)
|
|
genl_lock();
|
|
|
|
err = genl_family_rcv_msg(family, skb, nlh, extack);
|
|
|
|
if (!family->parallel_ops)
|
|
genl_unlock();
|
|
|
|
return err;
|
|
}
|
|
|
|
static void genl_rcv(struct sk_buff *skb)
|
|
{
|
|
down_read(&cb_lock);
|
|
netlink_rcv_skb(skb, &genl_rcv_msg);
|
|
up_read(&cb_lock);
|
|
}
|
|
|
|
/**************************************************************************
|
|
* Controller
|
|
**************************************************************************/
|
|
|
|
static struct genl_family genl_ctrl;
|
|
|
|
static int ctrl_fill_info(const struct genl_family *family, u32 portid, u32 seq,
|
|
u32 flags, struct sk_buff *skb, u8 cmd)
|
|
{
|
|
struct genl_op_iter i;
|
|
void *hdr;
|
|
|
|
hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd);
|
|
if (hdr == NULL)
|
|
return -1;
|
|
|
|
if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) ||
|
|
nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id) ||
|
|
nla_put_u32(skb, CTRL_ATTR_VERSION, family->version) ||
|
|
nla_put_u32(skb, CTRL_ATTR_HDRSIZE, family->hdrsize) ||
|
|
nla_put_u32(skb, CTRL_ATTR_MAXATTR, family->maxattr))
|
|
goto nla_put_failure;
|
|
|
|
if (genl_op_iter_init(family, &i)) {
|
|
struct nlattr *nla_ops;
|
|
|
|
nla_ops = nla_nest_start_noflag(skb, CTRL_ATTR_OPS);
|
|
if (nla_ops == NULL)
|
|
goto nla_put_failure;
|
|
|
|
while (genl_op_iter_next(&i)) {
|
|
struct nlattr *nest;
|
|
u32 op_flags;
|
|
|
|
op_flags = i.flags;
|
|
if (i.doit.policy || i.dumpit.policy)
|
|
op_flags |= GENL_CMD_CAP_HASPOL;
|
|
|
|
nest = nla_nest_start_noflag(skb, genl_op_iter_idx(&i));
|
|
if (nest == NULL)
|
|
goto nla_put_failure;
|
|
|
|
if (nla_put_u32(skb, CTRL_ATTR_OP_ID, i.cmd) ||
|
|
nla_put_u32(skb, CTRL_ATTR_OP_FLAGS, op_flags))
|
|
goto nla_put_failure;
|
|
|
|
nla_nest_end(skb, nest);
|
|
}
|
|
|
|
nla_nest_end(skb, nla_ops);
|
|
}
|
|
|
|
if (family->n_mcgrps) {
|
|
struct nlattr *nla_grps;
|
|
int i;
|
|
|
|
nla_grps = nla_nest_start_noflag(skb, CTRL_ATTR_MCAST_GROUPS);
|
|
if (nla_grps == NULL)
|
|
goto nla_put_failure;
|
|
|
|
for (i = 0; i < family->n_mcgrps; i++) {
|
|
struct nlattr *nest;
|
|
const struct genl_multicast_group *grp;
|
|
|
|
grp = &family->mcgrps[i];
|
|
|
|
nest = nla_nest_start_noflag(skb, i + 1);
|
|
if (nest == NULL)
|
|
goto nla_put_failure;
|
|
|
|
if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID,
|
|
family->mcgrp_offset + i) ||
|
|
nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME,
|
|
grp->name))
|
|
goto nla_put_failure;
|
|
|
|
nla_nest_end(skb, nest);
|
|
}
|
|
nla_nest_end(skb, nla_grps);
|
|
}
|
|
|
|
genlmsg_end(skb, hdr);
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
genlmsg_cancel(skb, hdr);
|
|
return -EMSGSIZE;
|
|
}
|
|
|
|
static int ctrl_fill_mcgrp_info(const struct genl_family *family,
|
|
const struct genl_multicast_group *grp,
|
|
int grp_id, u32 portid, u32 seq, u32 flags,
|
|
struct sk_buff *skb, u8 cmd)
|
|
{
|
|
void *hdr;
|
|
struct nlattr *nla_grps;
|
|
struct nlattr *nest;
|
|
|
|
hdr = genlmsg_put(skb, portid, seq, &genl_ctrl, flags, cmd);
|
|
if (hdr == NULL)
|
|
return -1;
|
|
|
|
if (nla_put_string(skb, CTRL_ATTR_FAMILY_NAME, family->name) ||
|
|
nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, family->id))
|
|
goto nla_put_failure;
|
|
|
|
nla_grps = nla_nest_start_noflag(skb, CTRL_ATTR_MCAST_GROUPS);
|
|
if (nla_grps == NULL)
|
|
goto nla_put_failure;
|
|
|
|
nest = nla_nest_start_noflag(skb, 1);
|
|
if (nest == NULL)
|
|
goto nla_put_failure;
|
|
|
|
if (nla_put_u32(skb, CTRL_ATTR_MCAST_GRP_ID, grp_id) ||
|
|
nla_put_string(skb, CTRL_ATTR_MCAST_GRP_NAME,
|
|
grp->name))
|
|
goto nla_put_failure;
|
|
|
|
nla_nest_end(skb, nest);
|
|
nla_nest_end(skb, nla_grps);
|
|
|
|
genlmsg_end(skb, hdr);
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
genlmsg_cancel(skb, hdr);
|
|
return -EMSGSIZE;
|
|
}
|
|
|
|
static int ctrl_dumpfamily(struct sk_buff *skb, struct netlink_callback *cb)
|
|
{
|
|
int n = 0;
|
|
struct genl_family *rt;
|
|
struct net *net = sock_net(skb->sk);
|
|
int fams_to_skip = cb->args[0];
|
|
unsigned int id;
|
|
|
|
idr_for_each_entry(&genl_fam_idr, rt, id) {
|
|
if (!rt->netnsok && !net_eq(net, &init_net))
|
|
continue;
|
|
|
|
if (n++ < fams_to_skip)
|
|
continue;
|
|
|
|
if (ctrl_fill_info(rt, NETLINK_CB(cb->skb).portid,
|
|
cb->nlh->nlmsg_seq, NLM_F_MULTI,
|
|
skb, CTRL_CMD_NEWFAMILY) < 0) {
|
|
n--;
|
|
break;
|
|
}
|
|
}
|
|
|
|
cb->args[0] = n;
|
|
return skb->len;
|
|
}
|
|
|
|
static struct sk_buff *ctrl_build_family_msg(const struct genl_family *family,
|
|
u32 portid, int seq, u8 cmd)
|
|
{
|
|
struct sk_buff *skb;
|
|
int err;
|
|
|
|
skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
|
|
if (skb == NULL)
|
|
return ERR_PTR(-ENOBUFS);
|
|
|
|
err = ctrl_fill_info(family, portid, seq, 0, skb, cmd);
|
|
if (err < 0) {
|
|
nlmsg_free(skb);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
return skb;
|
|
}
|
|
|
|
static struct sk_buff *
|
|
ctrl_build_mcgrp_msg(const struct genl_family *family,
|
|
const struct genl_multicast_group *grp,
|
|
int grp_id, u32 portid, int seq, u8 cmd)
|
|
{
|
|
struct sk_buff *skb;
|
|
int err;
|
|
|
|
skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
|
|
if (skb == NULL)
|
|
return ERR_PTR(-ENOBUFS);
|
|
|
|
err = ctrl_fill_mcgrp_info(family, grp, grp_id, portid,
|
|
seq, 0, skb, cmd);
|
|
if (err < 0) {
|
|
nlmsg_free(skb);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
return skb;
|
|
}
|
|
|
|
static const struct nla_policy ctrl_policy_family[] = {
|
|
[CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 },
|
|
[CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING,
|
|
.len = GENL_NAMSIZ - 1 },
|
|
};
|
|
|
|
static int ctrl_getfamily(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct sk_buff *msg;
|
|
const struct genl_family *res = NULL;
|
|
int err = -EINVAL;
|
|
|
|
if (info->attrs[CTRL_ATTR_FAMILY_ID]) {
|
|
u16 id = nla_get_u16(info->attrs[CTRL_ATTR_FAMILY_ID]);
|
|
res = genl_family_find_byid(id);
|
|
err = -ENOENT;
|
|
}
|
|
|
|
if (info->attrs[CTRL_ATTR_FAMILY_NAME]) {
|
|
char *name;
|
|
|
|
name = nla_data(info->attrs[CTRL_ATTR_FAMILY_NAME]);
|
|
res = genl_family_find_byname(name);
|
|
#ifdef CONFIG_MODULES
|
|
if (res == NULL) {
|
|
genl_unlock();
|
|
up_read(&cb_lock);
|
|
request_module("net-pf-%d-proto-%d-family-%s",
|
|
PF_NETLINK, NETLINK_GENERIC, name);
|
|
down_read(&cb_lock);
|
|
genl_lock();
|
|
res = genl_family_find_byname(name);
|
|
}
|
|
#endif
|
|
err = -ENOENT;
|
|
}
|
|
|
|
if (res == NULL)
|
|
return err;
|
|
|
|
if (!res->netnsok && !net_eq(genl_info_net(info), &init_net)) {
|
|
/* family doesn't exist here */
|
|
return -ENOENT;
|
|
}
|
|
|
|
msg = ctrl_build_family_msg(res, info->snd_portid, info->snd_seq,
|
|
CTRL_CMD_NEWFAMILY);
|
|
if (IS_ERR(msg))
|
|
return PTR_ERR(msg);
|
|
|
|
return genlmsg_reply(msg, info);
|
|
}
|
|
|
|
static int genl_ctrl_event(int event, const struct genl_family *family,
|
|
const struct genl_multicast_group *grp,
|
|
int grp_id)
|
|
{
|
|
struct sk_buff *msg;
|
|
|
|
/* genl is still initialising */
|
|
if (!init_net.genl_sock)
|
|
return 0;
|
|
|
|
switch (event) {
|
|
case CTRL_CMD_NEWFAMILY:
|
|
case CTRL_CMD_DELFAMILY:
|
|
WARN_ON(grp);
|
|
msg = ctrl_build_family_msg(family, 0, 0, event);
|
|
break;
|
|
case CTRL_CMD_NEWMCAST_GRP:
|
|
case CTRL_CMD_DELMCAST_GRP:
|
|
BUG_ON(!grp);
|
|
msg = ctrl_build_mcgrp_msg(family, grp, grp_id, 0, 0, event);
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (IS_ERR(msg))
|
|
return PTR_ERR(msg);
|
|
|
|
if (!family->netnsok) {
|
|
genlmsg_multicast_netns(&genl_ctrl, &init_net, msg, 0,
|
|
0, GFP_KERNEL);
|
|
} else {
|
|
rcu_read_lock();
|
|
genlmsg_multicast_allns(&genl_ctrl, msg, 0,
|
|
0, GFP_ATOMIC);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
struct ctrl_dump_policy_ctx {
|
|
struct netlink_policy_dump_state *state;
|
|
const struct genl_family *rt;
|
|
struct genl_op_iter *op_iter;
|
|
u32 op;
|
|
u16 fam_id;
|
|
u8 dump_map:1,
|
|
single_op:1;
|
|
};
|
|
|
|
static const struct nla_policy ctrl_policy_policy[] = {
|
|
[CTRL_ATTR_FAMILY_ID] = { .type = NLA_U16 },
|
|
[CTRL_ATTR_FAMILY_NAME] = { .type = NLA_NUL_STRING,
|
|
.len = GENL_NAMSIZ - 1 },
|
|
[CTRL_ATTR_OP] = { .type = NLA_U32 },
|
|
};
|
|
|
|
static int ctrl_dumppolicy_start(struct netlink_callback *cb)
|
|
{
|
|
const struct genl_dumpit_info *info = genl_dumpit_info(cb);
|
|
struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
|
|
struct nlattr **tb = info->attrs;
|
|
const struct genl_family *rt;
|
|
struct genl_op_iter i;
|
|
int err;
|
|
|
|
BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));
|
|
|
|
if (!tb[CTRL_ATTR_FAMILY_ID] && !tb[CTRL_ATTR_FAMILY_NAME])
|
|
return -EINVAL;
|
|
|
|
if (tb[CTRL_ATTR_FAMILY_ID]) {
|
|
ctx->fam_id = nla_get_u16(tb[CTRL_ATTR_FAMILY_ID]);
|
|
} else {
|
|
rt = genl_family_find_byname(
|
|
nla_data(tb[CTRL_ATTR_FAMILY_NAME]));
|
|
if (!rt)
|
|
return -ENOENT;
|
|
ctx->fam_id = rt->id;
|
|
}
|
|
|
|
rt = genl_family_find_byid(ctx->fam_id);
|
|
if (!rt)
|
|
return -ENOENT;
|
|
|
|
ctx->rt = rt;
|
|
|
|
if (tb[CTRL_ATTR_OP]) {
|
|
struct genl_split_ops doit, dump;
|
|
|
|
ctx->single_op = true;
|
|
ctx->op = nla_get_u32(tb[CTRL_ATTR_OP]);
|
|
|
|
err = genl_get_cmd_both(ctx->op, rt, &doit, &dump);
|
|
if (err) {
|
|
NL_SET_BAD_ATTR(cb->extack, tb[CTRL_ATTR_OP]);
|
|
return err;
|
|
}
|
|
|
|
if (doit.policy) {
|
|
err = netlink_policy_dump_add_policy(&ctx->state,
|
|
doit.policy,
|
|
doit.maxattr);
|
|
if (err)
|
|
goto err_free_state;
|
|
}
|
|
if (dump.policy) {
|
|
err = netlink_policy_dump_add_policy(&ctx->state,
|
|
dump.policy,
|
|
dump.maxattr);
|
|
if (err)
|
|
goto err_free_state;
|
|
}
|
|
|
|
if (!ctx->state)
|
|
return -ENODATA;
|
|
|
|
ctx->dump_map = 1;
|
|
return 0;
|
|
}
|
|
|
|
ctx->op_iter = kmalloc(sizeof(*ctx->op_iter), GFP_KERNEL);
|
|
if (!ctx->op_iter)
|
|
return -ENOMEM;
|
|
|
|
genl_op_iter_init(rt, ctx->op_iter);
|
|
ctx->dump_map = genl_op_iter_next(ctx->op_iter);
|
|
|
|
for (genl_op_iter_init(rt, &i); genl_op_iter_next(&i); ) {
|
|
if (i.doit.policy) {
|
|
err = netlink_policy_dump_add_policy(&ctx->state,
|
|
i.doit.policy,
|
|
i.doit.maxattr);
|
|
if (err)
|
|
goto err_free_state;
|
|
}
|
|
if (i.dumpit.policy) {
|
|
err = netlink_policy_dump_add_policy(&ctx->state,
|
|
i.dumpit.policy,
|
|
i.dumpit.maxattr);
|
|
if (err)
|
|
goto err_free_state;
|
|
}
|
|
}
|
|
|
|
if (!ctx->state) {
|
|
err = -ENODATA;
|
|
goto err_free_op_iter;
|
|
}
|
|
return 0;
|
|
|
|
err_free_state:
|
|
netlink_policy_dump_free(ctx->state);
|
|
err_free_op_iter:
|
|
kfree(ctx->op_iter);
|
|
return err;
|
|
}
|
|
|
|
static void *ctrl_dumppolicy_prep(struct sk_buff *skb,
|
|
struct netlink_callback *cb)
|
|
{
|
|
struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
|
|
void *hdr;
|
|
|
|
hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
|
|
cb->nlh->nlmsg_seq, &genl_ctrl,
|
|
NLM_F_MULTI, CTRL_CMD_GETPOLICY);
|
|
if (!hdr)
|
|
return NULL;
|
|
|
|
if (nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, ctx->fam_id))
|
|
return NULL;
|
|
|
|
return hdr;
|
|
}
|
|
|
|
static int ctrl_dumppolicy_put_op(struct sk_buff *skb,
|
|
struct netlink_callback *cb,
|
|
struct genl_split_ops *doit,
|
|
struct genl_split_ops *dumpit)
|
|
{
|
|
struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
|
|
struct nlattr *nest_pol, *nest_op;
|
|
void *hdr;
|
|
int idx;
|
|
|
|
/* skip if we have nothing to show */
|
|
if (!doit->policy && !dumpit->policy)
|
|
return 0;
|
|
|
|
hdr = ctrl_dumppolicy_prep(skb, cb);
|
|
if (!hdr)
|
|
return -ENOBUFS;
|
|
|
|
nest_pol = nla_nest_start(skb, CTRL_ATTR_OP_POLICY);
|
|
if (!nest_pol)
|
|
goto err;
|
|
|
|
nest_op = nla_nest_start(skb, doit->cmd);
|
|
if (!nest_op)
|
|
goto err;
|
|
|
|
if (doit->policy) {
|
|
idx = netlink_policy_dump_get_policy_idx(ctx->state,
|
|
doit->policy,
|
|
doit->maxattr);
|
|
|
|
if (nla_put_u32(skb, CTRL_ATTR_POLICY_DO, idx))
|
|
goto err;
|
|
}
|
|
if (dumpit->policy) {
|
|
idx = netlink_policy_dump_get_policy_idx(ctx->state,
|
|
dumpit->policy,
|
|
dumpit->maxattr);
|
|
|
|
if (nla_put_u32(skb, CTRL_ATTR_POLICY_DUMP, idx))
|
|
goto err;
|
|
}
|
|
|
|
nla_nest_end(skb, nest_op);
|
|
nla_nest_end(skb, nest_pol);
|
|
genlmsg_end(skb, hdr);
|
|
|
|
return 0;
|
|
err:
|
|
genlmsg_cancel(skb, hdr);
|
|
return -ENOBUFS;
|
|
}
|
|
|
|
static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb)
|
|
{
|
|
struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
|
|
void *hdr;
|
|
|
|
if (ctx->dump_map) {
|
|
if (ctx->single_op) {
|
|
struct genl_split_ops doit, dumpit;
|
|
|
|
if (WARN_ON(genl_get_cmd_both(ctx->op, ctx->rt,
|
|
&doit, &dumpit)))
|
|
return -ENOENT;
|
|
|
|
if (ctrl_dumppolicy_put_op(skb, cb, &doit, &dumpit))
|
|
return skb->len;
|
|
|
|
/* done with the per-op policy index list */
|
|
ctx->dump_map = 0;
|
|
}
|
|
|
|
while (ctx->dump_map) {
|
|
if (ctrl_dumppolicy_put_op(skb, cb,
|
|
&ctx->op_iter->doit,
|
|
&ctx->op_iter->dumpit))
|
|
return skb->len;
|
|
|
|
ctx->dump_map = genl_op_iter_next(ctx->op_iter);
|
|
}
|
|
}
|
|
|
|
while (netlink_policy_dump_loop(ctx->state)) {
|
|
struct nlattr *nest;
|
|
|
|
hdr = ctrl_dumppolicy_prep(skb, cb);
|
|
if (!hdr)
|
|
goto nla_put_failure;
|
|
|
|
nest = nla_nest_start(skb, CTRL_ATTR_POLICY);
|
|
if (!nest)
|
|
goto nla_put_failure;
|
|
|
|
if (netlink_policy_dump_write(skb, ctx->state))
|
|
goto nla_put_failure;
|
|
|
|
nla_nest_end(skb, nest);
|
|
|
|
genlmsg_end(skb, hdr);
|
|
}
|
|
|
|
return skb->len;
|
|
|
|
nla_put_failure:
|
|
genlmsg_cancel(skb, hdr);
|
|
return skb->len;
|
|
}
|
|
|
|
static int ctrl_dumppolicy_done(struct netlink_callback *cb)
|
|
{
|
|
struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
|
|
|
|
kfree(ctx->op_iter);
|
|
netlink_policy_dump_free(ctx->state);
|
|
return 0;
|
|
}
|
|
|
|
static const struct genl_split_ops genl_ctrl_ops[] = {
|
|
{
|
|
.cmd = CTRL_CMD_GETFAMILY,
|
|
.validate = GENL_DONT_VALIDATE_STRICT,
|
|
.policy = ctrl_policy_family,
|
|
.maxattr = ARRAY_SIZE(ctrl_policy_family) - 1,
|
|
.doit = ctrl_getfamily,
|
|
.flags = GENL_CMD_CAP_DO,
|
|
},
|
|
{
|
|
.cmd = CTRL_CMD_GETFAMILY,
|
|
.validate = GENL_DONT_VALIDATE_DUMP,
|
|
.policy = ctrl_policy_family,
|
|
.maxattr = ARRAY_SIZE(ctrl_policy_family) - 1,
|
|
.dumpit = ctrl_dumpfamily,
|
|
.flags = GENL_CMD_CAP_DUMP,
|
|
},
|
|
{
|
|
.cmd = CTRL_CMD_GETPOLICY,
|
|
.policy = ctrl_policy_policy,
|
|
.maxattr = ARRAY_SIZE(ctrl_policy_policy) - 1,
|
|
.start = ctrl_dumppolicy_start,
|
|
.dumpit = ctrl_dumppolicy,
|
|
.done = ctrl_dumppolicy_done,
|
|
.flags = GENL_CMD_CAP_DUMP,
|
|
},
|
|
};
|
|
|
|
static const struct genl_multicast_group genl_ctrl_groups[] = {
|
|
{ .name = "notify", },
|
|
};
|
|
|
|
static struct genl_family genl_ctrl __ro_after_init = {
|
|
.module = THIS_MODULE,
|
|
.split_ops = genl_ctrl_ops,
|
|
.n_split_ops = ARRAY_SIZE(genl_ctrl_ops),
|
|
.resv_start_op = CTRL_CMD_GETPOLICY + 1,
|
|
.mcgrps = genl_ctrl_groups,
|
|
.n_mcgrps = ARRAY_SIZE(genl_ctrl_groups),
|
|
.id = GENL_ID_CTRL,
|
|
.name = "nlctrl",
|
|
.version = 0x2,
|
|
.netnsok = true,
|
|
};
|
|
|
|
static int genl_bind(struct net *net, int group)
|
|
{
|
|
const struct genl_family *family;
|
|
unsigned int id;
|
|
int ret = 0;
|
|
|
|
down_read(&cb_lock);
|
|
|
|
idr_for_each_entry(&genl_fam_idr, family, id) {
|
|
const struct genl_multicast_group *grp;
|
|
int i;
|
|
|
|
if (family->n_mcgrps == 0)
|
|
continue;
|
|
|
|
i = group - family->mcgrp_offset;
|
|
if (i < 0 || i >= family->n_mcgrps)
|
|
continue;
|
|
|
|
grp = &family->mcgrps[i];
|
|
if ((grp->flags & GENL_UNS_ADMIN_PERM) &&
|
|
!ns_capable(net->user_ns, CAP_NET_ADMIN))
|
|
ret = -EPERM;
|
|
|
|
break;
|
|
}
|
|
|
|
up_read(&cb_lock);
|
|
return ret;
|
|
}
|
|
|
|
static int __net_init genl_pernet_init(struct net *net)
|
|
{
|
|
struct netlink_kernel_cfg cfg = {
|
|
.input = genl_rcv,
|
|
.flags = NL_CFG_F_NONROOT_RECV,
|
|
.bind = genl_bind,
|
|
};
|
|
|
|
/* we'll bump the group number right afterwards */
|
|
net->genl_sock = netlink_kernel_create(net, NETLINK_GENERIC, &cfg);
|
|
|
|
if (!net->genl_sock && net_eq(net, &init_net))
|
|
panic("GENL: Cannot initialize generic netlink\n");
|
|
|
|
if (!net->genl_sock)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __net_exit genl_pernet_exit(struct net *net)
|
|
{
|
|
netlink_kernel_release(net->genl_sock);
|
|
net->genl_sock = NULL;
|
|
}
|
|
|
|
static struct pernet_operations genl_pernet_ops = {
|
|
.init = genl_pernet_init,
|
|
.exit = genl_pernet_exit,
|
|
};
|
|
|
|
static int __init genl_init(void)
|
|
{
|
|
int err;
|
|
|
|
err = genl_register_family(&genl_ctrl);
|
|
if (err < 0)
|
|
goto problem;
|
|
|
|
err = register_pernet_subsys(&genl_pernet_ops);
|
|
if (err)
|
|
goto problem;
|
|
|
|
return 0;
|
|
|
|
problem:
|
|
panic("GENL: Cannot register controller: %d\n", err);
|
|
}
|
|
|
|
core_initcall(genl_init);
|
|
|
|
static int genlmsg_mcast(struct sk_buff *skb, u32 portid, unsigned long group,
|
|
gfp_t flags)
|
|
{
|
|
struct sk_buff *tmp;
|
|
struct net *net, *prev = NULL;
|
|
bool delivered = false;
|
|
int err;
|
|
|
|
for_each_net_rcu(net) {
|
|
if (prev) {
|
|
tmp = skb_clone(skb, flags);
|
|
if (!tmp) {
|
|
err = -ENOMEM;
|
|
goto error;
|
|
}
|
|
err = nlmsg_multicast(prev->genl_sock, tmp,
|
|
portid, group, flags);
|
|
if (!err)
|
|
delivered = true;
|
|
else if (err != -ESRCH)
|
|
goto error;
|
|
}
|
|
|
|
prev = net;
|
|
}
|
|
|
|
err = nlmsg_multicast(prev->genl_sock, skb, portid, group, flags);
|
|
if (!err)
|
|
delivered = true;
|
|
else if (err != -ESRCH)
|
|
return err;
|
|
return delivered ? 0 : -ESRCH;
|
|
error:
|
|
kfree_skb(skb);
|
|
return err;
|
|
}
|
|
|
|
int genlmsg_multicast_allns(const struct genl_family *family,
|
|
struct sk_buff *skb, u32 portid,
|
|
unsigned int group, gfp_t flags)
|
|
{
|
|
if (WARN_ON_ONCE(group >= family->n_mcgrps))
|
|
return -EINVAL;
|
|
|
|
group = family->mcgrp_offset + group;
|
|
return genlmsg_mcast(skb, portid, group, flags);
|
|
}
|
|
EXPORT_SYMBOL(genlmsg_multicast_allns);
|
|
|
|
void genl_notify(const struct genl_family *family, struct sk_buff *skb,
|
|
struct genl_info *info, u32 group, gfp_t flags)
|
|
{
|
|
struct net *net = genl_info_net(info);
|
|
struct sock *sk = net->genl_sock;
|
|
|
|
if (WARN_ON_ONCE(group >= family->n_mcgrps))
|
|
return;
|
|
|
|
group = family->mcgrp_offset + group;
|
|
nlmsg_notify(sk, skb, info->snd_portid, group,
|
|
nlmsg_report(info->nlhdr), flags);
|
|
}
|
|
EXPORT_SYMBOL(genl_notify);
|