include/net/rtnetlink.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __NET_RTNETLINK_H
   3 #define __NET_RTNETLINK_H
   4
   5 #include <linux/rtnetlink.h>
   6 #include <linux/srcu.h>
   7 #include <net/netlink.h>
   8
   9 typedef int (*rtnl_doit_func)(struct sk_buff *, struct nlmsghdr *,
  10                               struct netlink_ext_ack *);
  11 typedef int (*rtnl_dumpit_func)(struct sk_buff *, struct netlink_callback *);
  12
  13 enum rtnl_link_flags {
  14         RTNL_FLAG_DOIT_UNLOCKED         = BIT(0),
  15 #define RTNL_FLAG_DOIT_PERNET           RTNL_FLAG_DOIT_UNLOCKED
  16 #define RTNL_FLAG_DOIT_PERNET_WIP       RTNL_FLAG_DOIT_UNLOCKED
  17         RTNL_FLAG_BULK_DEL_SUPPORTED    = BIT(1),
  18         RTNL_FLAG_DUMP_UNLOCKED         = BIT(2),
  19         RTNL_FLAG_DUMP_SPLIT_NLM_DONE   = BIT(3),       /* legacy behavior */
  20 };
  21
  22 enum rtnl_kinds {
  23         RTNL_KIND_NEW,
  24         RTNL_KIND_DEL,
  25         RTNL_KIND_GET,
  26         RTNL_KIND_SET
  27 };
  28 #define RTNL_KIND_MASK 0x3
  29
  30 static inline enum rtnl_kinds rtnl_msgtype_kind(int msgtype)
  31 {
  32         return msgtype & RTNL_KIND_MASK;
  33 }
  34
  35 /**
  36  *      struct rtnl_msg_handler - rtnetlink message type and handlers
  37  *
  38  *      @owner: NULL for built-in, THIS_MODULE for module
  39  *      @protocol: Protocol family or PF_UNSPEC
  40  *      @msgtype: rtnetlink message type
  41  *      @doit: Function pointer called for each request message
  42  *      @dumpit: Function pointer called for each dump request (NLM_F_DUMP) message
  43  *      @flags: rtnl_link_flags to modify behaviour of doit/dumpit functions
  44  */
  45 struct rtnl_msg_handler {
  46         struct module *owner;
  47         int protocol;
  48         int msgtype;
  49         rtnl_doit_func doit;
  50         rtnl_dumpit_func dumpit;
  51         int flags;
  52 };
  53
  54 void rtnl_unregister_all(int protocol);
  55
  56 int __rtnl_register_many(const struct rtnl_msg_handler *handlers, int n);
  57 void __rtnl_unregister_many(const struct rtnl_msg_handler *handlers, int n);
  58
  59 #define rtnl_register_many(handlers)                            \
  60         __rtnl_register_many(handlers, ARRAY_SIZE(handlers))
  61 #define rtnl_unregister_many(handlers)                          \
  62         __rtnl_unregister_many(handlers, ARRAY_SIZE(handlers))
  63
  64 static inline int rtnl_msg_family(const struct nlmsghdr *nlh)
  65 {
  66         if (nlmsg_len(nlh) >= sizeof(struct rtgenmsg))
  67                 return ((struct rtgenmsg *) nlmsg_data(nlh))->rtgen_family;
  68         else
  69                 return AF_UNSPEC;
  70 }
  71
  72 /**
  73  *      struct rtnl_link_ops - rtnetlink link operations
  74  *
  75  *      @list: Used internally, protected by link_ops_mutex and SRCU
  76  *      @srcu: Used internally
  77  *      @kind: Identifier
  78  *      @netns_refund: Physical device, move to init_net on netns exit
  79  *      @peer_type: Peer device specific netlink attribute number (e.g. VETH_INFO_PEER)
  80  *      @maxtype: Highest device specific netlink attribute number
  81  *      @policy: Netlink policy for device specific attribute validation
  82  *      @validate: Optional validation function for netlink/changelink parameters
  83  *      @alloc: netdev allocation function, can be %NULL and is then used
  84  *              in place of alloc_netdev_mqs(), in this case @priv_size
  85  *              and @setup are unused. Returns a netdev or ERR_PTR().
  86  *      @priv_size: sizeof net_device private space
  87  *      @setup: net_device setup function
  88  *      @newlink: Function for configuring and registering a new device
  89  *      @changelink: Function for changing parameters of an existing device
  90  *      @dellink: Function to remove a device
  91  *      @get_size: Function to calculate required room for dumping device
  92  *                 specific netlink attributes
  93  *      @fill_info: Function to dump device specific netlink attributes
  94  *      @get_xstats_size: Function to calculate required room for dumping device
  95  *                        specific statistics
  96  *      @fill_xstats: Function to dump device specific statistics
  97  *      @get_num_tx_queues: Function to determine number of transmit queues
  98  *                          to create when creating a new device.
  99  *      @get_num_rx_queues: Function to determine number of receive queues
 100  *                          to create when creating a new device.
 101  *      @get_link_net: Function to get the i/o netns of the device
 102  *      @get_linkxstats_size: Function to calculate the required room for
 103  *                            dumping device-specific extended link stats
 104  *      @fill_linkxstats: Function to dump device-specific extended link stats
 105  */
 106 struct rtnl_link_ops {
 107         struct list_head        list;
 108         struct srcu_struct      srcu;
 109
 110         const char              *kind;
 111
 112         size_t                  priv_size;
 113         struct net_device       *(*alloc)(struct nlattr *tb[],
 114                                           const char *ifname,
 115                                           unsigned char name_assign_type,
 116                                           unsigned int num_tx_queues,
 117                                           unsigned int num_rx_queues);
 118         void                    (*setup)(struct net_device *dev);
 119
 120         bool                    netns_refund;
 121         const u16               peer_type;
 122         unsigned int            maxtype;
 123         const struct nla_policy *policy;
 124         int                     (*validate)(struct nlattr *tb[],
 125                                             struct nlattr *data[],
 126                                             struct netlink_ext_ack *extack);
 127
 128         int                     (*newlink)(struct net *src_net,
 129                                            struct net_device *dev,
 130                                            struct nlattr *tb[],
 131                                            struct nlattr *data[],
 132                                            struct netlink_ext_ack *extack);
 133         int                     (*changelink)(struct net_device *dev,
 134                                               struct nlattr *tb[],
 135                                               struct nlattr *data[],
 136                                               struct netlink_ext_ack *extack);
 137         void                    (*dellink)(struct net_device *dev,
 138                                            struct list_head *head);
 139
 140         size_t                  (*get_size)(const struct net_device *dev);
 141         int                     (*fill_info)(struct sk_buff *skb,
 142                                              const struct net_device *dev);
 143
 144         size_t                  (*get_xstats_size)(const struct net_device *dev);
 145         int                     (*fill_xstats)(struct sk_buff *skb,
 146                                                const struct net_device *dev);
 147         unsigned int            (*get_num_tx_queues)(void);
 148         unsigned int            (*get_num_rx_queues)(void);
 149
 150         unsigned int            slave_maxtype;
 151         const struct nla_policy *slave_policy;
 152         int                     (*slave_changelink)(struct net_device *dev,
 153                                                     struct net_device *slave_dev,
 154                                                     struct nlattr *tb[],
 155                                                     struct nlattr *data[],
 156                                                     struct netlink_ext_ack *extack);
 157         size_t                  (*get_slave_size)(const struct net_device *dev,
 158                                                   const struct net_device *slave_dev);
 159         int                     (*fill_slave_info)(struct sk_buff *skb,
 160                                                    const struct net_device *dev,
 161                                                    const struct net_device *slave_dev);
 162         struct net              *(*get_link_net)(const struct net_device *dev);
 163         size_t                  (*get_linkxstats_size)(const struct net_device *dev,
 164                                                        int attr);
 165         int                     (*fill_linkxstats)(struct sk_buff *skb,
 166                                                    const struct net_device *dev,
 167                                                    int *prividx, int attr);
 168 };
 169
 170 int rtnl_link_register(struct rtnl_link_ops *ops);
 171 void rtnl_link_unregister(struct rtnl_link_ops *ops);
 172
 173 /**
 174  *      struct rtnl_af_ops - rtnetlink address family operations
 175  *
 176  *      @list: Used internally, protected by RTNL and SRCU
 177  *      @srcu: Used internally
 178  *      @family: Address family
 179  *      @fill_link_af: Function to fill IFLA_AF_SPEC with address family
 180  *                     specific netlink attributes.
 181  *      @get_link_af_size: Function to calculate size of address family specific
 182  *                         netlink attributes.
 183  *      @validate_link_af: Validate a IFLA_AF_SPEC attribute, must check attr
 184  *                         for invalid configuration settings.
 185  *      @set_link_af: Function to parse a IFLA_AF_SPEC attribute and modify
 186  *                    net_device accordingly.
 187  */
 188 struct rtnl_af_ops {
 189         struct list_head        list;
 190         struct srcu_struct      srcu;
 191
 192         int                     family;
 193
 194         int                     (*fill_link_af)(struct sk_buff *skb,
 195                                                 const struct net_device *dev,
 196                                                 u32 ext_filter_mask);
 197         size_t                  (*get_link_af_size)(const struct net_device *dev,
 198                                                     u32 ext_filter_mask);
 199
 200         int                     (*validate_link_af)(const struct net_device *dev,
 201                                                     const struct nlattr *attr,
 202                                                     struct netlink_ext_ack *extack);
 203         int                     (*set_link_af)(struct net_device *dev,
 204                                                const struct nlattr *attr,
 205                                                struct netlink_ext_ack *extack);
 206         int                     (*fill_stats_af)(struct sk_buff *skb,
 207                                                  const struct net_device *dev);
 208         size_t                  (*get_stats_af_size)(const struct net_device *dev);
 209 };
 210
 211 int rtnl_af_register(struct rtnl_af_ops *ops);
 212 void rtnl_af_unregister(struct rtnl_af_ops *ops);
 213
 214 struct net *rtnl_link_get_net(struct net *src_net, struct nlattr *tb[]);
 215 struct net_device *rtnl_create_link(struct net *net, const char *ifname,
 216                                     unsigned char name_assign_type,
 217                                     const struct rtnl_link_ops *ops,
 218                                     struct nlattr *tb[],
 219                                     struct netlink_ext_ack *extack);
 220 int rtnl_delete_link(struct net_device *dev, u32 portid, const struct nlmsghdr *nlh);
 221 int rtnl_configure_link(struct net_device *dev, const struct ifinfomsg *ifm,
 222                         u32 portid, const struct nlmsghdr *nlh);
 223
 224 int rtnl_nla_parse_ifinfomsg(struct nlattr **tb, const struct nlattr *nla_peer,
 225                              struct netlink_ext_ack *exterr);
 226 struct net *rtnl_get_net_ns_capable(struct sock *sk, int netnsid);
 227
 228 #define MODULE_ALIAS_RTNL_LINK(kind) MODULE_ALIAS("rtnl-link-" kind)
 229
 230 #endif