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Diffstat (limited to 'include/linux/netlink.h')
-rw-r--r--include/linux/netlink.h132
1 files changed, 109 insertions, 23 deletions
diff --git a/include/linux/netlink.h b/include/linux/netlink.h
index 9f118771e248..882e9c1b6c1d 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h
@@ -11,6 +11,8 @@
struct net;
+void do_trace_netlink_extack(const char *msg);
+
static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
{
return (struct nlmsghdr *)skb->data;
@@ -32,6 +34,7 @@ struct netlink_skb_parms {
#define NETLINK_CB(skb) (*(struct netlink_skb_parms*)&((skb)->cb))
#define NETLINK_CREDS(skb) (&NETLINK_CB((skb)).creds)
+#define NETLINK_CTX_SIZE 48
void netlink_table_grab(void);
@@ -45,10 +48,9 @@ struct netlink_kernel_cfg {
unsigned int groups;
unsigned int flags;
void (*input)(struct sk_buff *skb);
- struct mutex *cb_mutex;
int (*bind)(struct net *net, int group);
void (*unbind)(struct net *net, int group);
- bool (*compare)(struct net *net, struct sock *sk);
+ void (*release) (struct sock *sk, unsigned long *groups);
};
struct sock *__netlink_kernel_create(struct net *net, int unit,
@@ -61,7 +63,8 @@ netlink_kernel_create(struct net *net, int unit, struct netlink_kernel_cfg *cfg)
}
/* this can be increased when necessary - don't expose to userland */
-#define NETLINK_MAX_COOKIE_LEN 20
+#define NETLINK_MAX_COOKIE_LEN 8
+#define NETLINK_MAX_FMTMSG_LEN 80
/**
* struct netlink_ext_ack - netlink extended ACK report struct
@@ -69,34 +72,74 @@ netlink_kernel_create(struct net *net, int unit, struct netlink_kernel_cfg *cfg)
* %NL_SET_ERR_MSG
* @bad_attr: attribute with error
* @policy: policy for a bad attribute
+ * @miss_type: attribute type which was missing
+ * @miss_nest: nest missing an attribute (%NULL if missing top level attr)
* @cookie: cookie data to return to userspace (for success)
* @cookie_len: actual cookie data length
+ * @_msg_buf: output buffer for formatted message strings - don't access
+ * directly, use %NL_SET_ERR_MSG_FMT
*/
struct netlink_ext_ack {
const char *_msg;
const struct nlattr *bad_attr;
const struct nla_policy *policy;
+ const struct nlattr *miss_nest;
+ u16 miss_type;
u8 cookie[NETLINK_MAX_COOKIE_LEN];
u8 cookie_len;
+ char _msg_buf[NETLINK_MAX_FMTMSG_LEN];
};
/* Always use this macro, this allows later putting the
* message into a separate section or such for things
* like translation or listing all possible messages.
- * Currently string formatting is not supported (due
- * to the lack of an output buffer.)
+ * If string formatting is needed use NL_SET_ERR_MSG_FMT.
*/
#define NL_SET_ERR_MSG(extack, msg) do { \
static const char __msg[] = msg; \
struct netlink_ext_ack *__extack = (extack); \
\
+ do_trace_netlink_extack(__msg); \
+ \
if (__extack) \
__extack->_msg = __msg; \
} while (0)
+/* We splice fmt with %s at each end even in the snprintf so that both calls
+ * can use the same string constant, avoiding its duplication in .ro
+ */
+#define NL_SET_ERR_MSG_FMT(extack, fmt, args...) do { \
+ struct netlink_ext_ack *__extack = (extack); \
+ \
+ if (!__extack) \
+ break; \
+ if (snprintf(__extack->_msg_buf, NETLINK_MAX_FMTMSG_LEN, \
+ "%s" fmt "%s", "", ##args, "") >= \
+ NETLINK_MAX_FMTMSG_LEN) \
+ net_warn_ratelimited("%s" fmt "%s", "truncated extack: ", \
+ ##args, "\n"); \
+ \
+ do_trace_netlink_extack(__extack->_msg_buf); \
+ \
+ __extack->_msg = __extack->_msg_buf; \
+} while (0)
+
#define NL_SET_ERR_MSG_MOD(extack, msg) \
NL_SET_ERR_MSG((extack), KBUILD_MODNAME ": " msg)
+#define NL_SET_ERR_MSG_FMT_MOD(extack, fmt, args...) \
+ NL_SET_ERR_MSG_FMT((extack), KBUILD_MODNAME ": " fmt, ##args)
+
+#define NL_SET_ERR_MSG_WEAK(extack, msg) do { \
+ if ((extack) && !(extack)->_msg) \
+ NL_SET_ERR_MSG((extack), msg); \
+} while (0)
+
+#define NL_SET_ERR_MSG_WEAK_MOD(extack, msg) do { \
+ if ((extack) && !(extack)->_msg) \
+ NL_SET_ERR_MSG_MOD((extack), msg); \
+} while (0)
+
#define NL_SET_BAD_ATTR_POLICY(extack, attr, pol) do { \
if ((extack)) { \
(extack)->bad_attr = (attr); \
@@ -110,6 +153,8 @@ struct netlink_ext_ack {
static const char __msg[] = msg; \
struct netlink_ext_ack *__extack = (extack); \
\
+ do_trace_netlink_extack(__msg); \
+ \
if (__extack) { \
__extack->_msg = __msg; \
__extack->bad_attr = (attr); \
@@ -117,29 +162,59 @@ struct netlink_ext_ack {
} \
} while (0)
+#define NL_SET_ERR_MSG_ATTR_POL_FMT(extack, attr, pol, fmt, args...) do { \
+ struct netlink_ext_ack *__extack = (extack); \
+ \
+ if (!__extack) \
+ break; \
+ \
+ if (snprintf(__extack->_msg_buf, NETLINK_MAX_FMTMSG_LEN, \
+ "%s" fmt "%s", "", ##args, "") >= \
+ NETLINK_MAX_FMTMSG_LEN) \
+ net_warn_ratelimited("%s" fmt "%s", "truncated extack: ", \
+ ##args, "\n"); \
+ \
+ do_trace_netlink_extack(__extack->_msg_buf); \
+ \
+ __extack->_msg = __extack->_msg_buf; \
+ __extack->bad_attr = (attr); \
+ __extack->policy = (pol); \
+} while (0)
+
#define NL_SET_ERR_MSG_ATTR(extack, attr, msg) \
NL_SET_ERR_MSG_ATTR_POL(extack, attr, NULL, msg)
-static inline void nl_set_extack_cookie_u64(struct netlink_ext_ack *extack,
- u64 cookie)
-{
- u64 __cookie = cookie;
+#define NL_SET_ERR_MSG_ATTR_FMT(extack, attr, msg, args...) \
+ NL_SET_ERR_MSG_ATTR_POL_FMT(extack, attr, NULL, msg, ##args)
- if (!extack)
- return;
- memcpy(extack->cookie, &__cookie, sizeof(__cookie));
- extack->cookie_len = sizeof(__cookie);
-}
+#define NL_SET_ERR_ATTR_MISS(extack, nest, type) do { \
+ struct netlink_ext_ack *__extack = (extack); \
+ \
+ if (__extack) { \
+ __extack->miss_nest = (nest); \
+ __extack->miss_type = (type); \
+ } \
+} while (0)
-static inline void nl_set_extack_cookie_u32(struct netlink_ext_ack *extack,
- u32 cookie)
-{
- u32 __cookie = cookie;
+#define NL_REQ_ATTR_CHECK(extack, nest, tb, type) ({ \
+ struct nlattr **__tb = (tb); \
+ u32 __attr = (type); \
+ int __retval; \
+ \
+ __retval = !__tb[__attr]; \
+ if (__retval) \
+ NL_SET_ERR_ATTR_MISS((extack), (nest), __attr); \
+ __retval; \
+})
+static inline void nl_set_extack_cookie_u64(struct netlink_ext_ack *extack,
+ u64 cookie)
+{
if (!extack)
return;
- memcpy(extack->cookie, &__cookie, sizeof(__cookie));
- extack->cookie_len = sizeof(__cookie);
+ BUILD_BUG_ON(sizeof(extack->cookie) < sizeof(cookie));
+ memcpy(extack->cookie, &cookie, sizeof(cookie));
+ extack->cookie_len = sizeof(cookie);
}
void netlink_kernel_release(struct sock *sk);
@@ -154,16 +229,19 @@ bool netlink_strict_get_check(struct sk_buff *skb);
int netlink_unicast(struct sock *ssk, struct sk_buff *skb, __u32 portid, int nonblock);
int netlink_broadcast(struct sock *ssk, struct sk_buff *skb, __u32 portid,
__u32 group, gfp_t allocation);
+
+typedef int (*netlink_filter_fn)(struct sock *dsk, struct sk_buff *skb, void *data);
+
int netlink_broadcast_filtered(struct sock *ssk, struct sk_buff *skb,
__u32 portid, __u32 group, gfp_t allocation,
- int (*filter)(struct sock *dsk, struct sk_buff *skb, void *data),
+ netlink_filter_fn filter,
void *filter_data);
int netlink_set_err(struct sock *ssk, __u32 portid, __u32 group, int code);
int netlink_register_notifier(struct notifier_block *nb);
int netlink_unregister_notifier(struct notifier_block *nb);
/* finegrained unicast helpers: */
-struct sock *netlink_getsockbyfilp(struct file *filp);
+struct sock *netlink_getsockbyfd(int fd);
int netlink_attachskb(struct sock *sk, struct sk_buff *skb,
long *timeo, struct sock *ssk);
void netlink_detachskb(struct sock *sk, struct sk_buff *skb);
@@ -214,9 +292,10 @@ struct netlink_callback {
u16 answer_flags;
u32 min_dump_alloc;
unsigned int prev_seq, seq;
+ int flags;
bool strict_check;
union {
- u8 ctx[48];
+ u8 ctx[NETLINK_CTX_SIZE];
/* args is deprecated. Cast a struct over ctx instead
* for proper type safety.
@@ -225,6 +304,10 @@ struct netlink_callback {
};
};
+#define NL_ASSERT_CTX_FITS(type_name) \
+ BUILD_BUG_ON(sizeof(type_name) > \
+ sizeof_field(struct netlink_callback, ctx))
+
struct netlink_notify {
struct net *net;
u32 portid;
@@ -238,9 +321,11 @@ struct netlink_dump_control {
int (*start)(struct netlink_callback *);
int (*dump)(struct sk_buff *skb, struct netlink_callback *);
int (*done)(struct netlink_callback *);
+ struct netlink_ext_ack *extack;
void *data;
struct module *module;
u32 min_dump_alloc;
+ int flags;
};
int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
@@ -271,5 +356,6 @@ bool netlink_ns_capable(const struct sk_buff *skb,
struct user_namespace *ns, int cap);
bool netlink_capable(const struct sk_buff *skb, int cap);
bool netlink_net_capable(const struct sk_buff *skb, int cap);
+struct sk_buff *netlink_alloc_large_skb(unsigned int size, int broadcast);
#endif /* __LINUX_NETLINK_H */
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.