1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright (c) 2017 - 2018 Covalent IO, Inc. http://covalent.io */
8 #include <linux/filter.h>
9 #include <linux/scatterlist.h>
10 #include <linux/skbuff.h>
14 #include <net/strparser.h>
16 #define MAX_MSG_FRAGS MAX_SKB_FRAGS
31 bool copy[MAX_MSG_FRAGS];
32 /* The extra element is used for chaining the front and sections when
33 * the list becomes partitioned (e.g. end < start). The crypto APIs
34 * require the chaining.
36 struct scatterlist data[MAX_MSG_FRAGS + 1];
39 /* UAPI in filter.c depends on struct sk_msg_sg being first element. */
48 struct sock *sk_redir;
50 struct list_head list;
53 struct sk_psock_progs {
54 struct bpf_prog *msg_parser;
55 struct bpf_prog *skb_parser;
56 struct bpf_prog *skb_verdict;
59 enum sk_psock_state_bits {
63 struct sk_psock_link {
64 struct list_head list;
69 struct sk_psock_parser {
70 struct strparser strp;
72 void (*saved_data_ready)(struct sock *sk);
75 struct sk_psock_work_state {
83 struct sock *sk_redir;
88 struct sk_psock_progs progs;
89 struct sk_psock_parser parser;
90 struct sk_buff_head ingress_skb;
91 struct list_head ingress_msg;
93 struct list_head link;
96 void (*saved_unhash)(struct sock *sk);
97 void (*saved_close)(struct sock *sk, long timeout);
98 void (*saved_write_space)(struct sock *sk);
99 struct proto *sk_proto;
100 struct sk_psock_work_state work_state;
101 struct work_struct work;
104 struct work_struct gc;
108 int sk_msg_alloc(struct sock *sk, struct sk_msg *msg, int len,
109 int elem_first_coalesce);
110 int sk_msg_clone(struct sock *sk, struct sk_msg *dst, struct sk_msg *src,
112 void sk_msg_trim(struct sock *sk, struct sk_msg *msg, int len);
113 int sk_msg_free(struct sock *sk, struct sk_msg *msg);
114 int sk_msg_free_nocharge(struct sock *sk, struct sk_msg *msg);
115 void sk_msg_free_partial(struct sock *sk, struct sk_msg *msg, u32 bytes);
116 void sk_msg_free_partial_nocharge(struct sock *sk, struct sk_msg *msg,
119 void sk_msg_return(struct sock *sk, struct sk_msg *msg, int bytes);
120 void sk_msg_return_zero(struct sock *sk, struct sk_msg *msg, int bytes);
122 int sk_msg_zerocopy_from_iter(struct sock *sk, struct iov_iter *from,
123 struct sk_msg *msg, u32 bytes);
124 int sk_msg_memcopy_from_iter(struct sock *sk, struct iov_iter *from,
125 struct sk_msg *msg, u32 bytes);
127 static inline void sk_msg_check_to_free(struct sk_msg *msg, u32 i, u32 bytes)
129 WARN_ON(i == msg->sg.end && bytes);
132 static inline void sk_msg_apply_bytes(struct sk_psock *psock, u32 bytes)
134 if (psock->apply_bytes) {
135 if (psock->apply_bytes < bytes)
136 psock->apply_bytes = 0;
138 psock->apply_bytes -= bytes;
142 #define sk_msg_iter_var_prev(var) \
145 var = MAX_MSG_FRAGS - 1; \
150 #define sk_msg_iter_var_next(var) \
153 if (var == MAX_MSG_FRAGS) \
157 #define sk_msg_iter_prev(msg, which) \
158 sk_msg_iter_var_prev(msg->sg.which)
160 #define sk_msg_iter_next(msg, which) \
161 sk_msg_iter_var_next(msg->sg.which)
163 static inline void sk_msg_clear_meta(struct sk_msg *msg)
165 memset(&msg->sg, 0, offsetofend(struct sk_msg_sg, copy));
168 static inline void sk_msg_init(struct sk_msg *msg)
170 BUILD_BUG_ON(ARRAY_SIZE(msg->sg.data) - 1 != MAX_MSG_FRAGS);
171 memset(msg, 0, sizeof(*msg));
172 sg_init_marker(msg->sg.data, MAX_MSG_FRAGS);
175 static inline void sk_msg_xfer(struct sk_msg *dst, struct sk_msg *src,
178 dst->sg.data[which] = src->sg.data[which];
179 dst->sg.data[which].length = size;
180 dst->sg.size += size;
181 src->sg.data[which].length -= size;
182 src->sg.data[which].offset += size;
185 static inline void sk_msg_xfer_full(struct sk_msg *dst, struct sk_msg *src)
187 memcpy(dst, src, sizeof(*src));
191 static inline bool sk_msg_full(const struct sk_msg *msg)
193 return (msg->sg.end == msg->sg.start) && msg->sg.size;
196 static inline u32 sk_msg_elem_used(const struct sk_msg *msg)
198 if (sk_msg_full(msg))
199 return MAX_MSG_FRAGS;
201 return msg->sg.end >= msg->sg.start ?
202 msg->sg.end - msg->sg.start :
203 msg->sg.end + (MAX_MSG_FRAGS - msg->sg.start);
206 static inline struct scatterlist *sk_msg_elem(struct sk_msg *msg, int which)
208 return &msg->sg.data[which];
211 static inline struct scatterlist sk_msg_elem_cpy(struct sk_msg *msg, int which)
213 return msg->sg.data[which];
216 static inline struct page *sk_msg_page(struct sk_msg *msg, int which)
218 return sg_page(sk_msg_elem(msg, which));
221 static inline bool sk_msg_to_ingress(const struct sk_msg *msg)
223 return msg->flags & BPF_F_INGRESS;
226 static inline void sk_msg_compute_data_pointers(struct sk_msg *msg)
228 struct scatterlist *sge = sk_msg_elem(msg, msg->sg.start);
230 if (msg->sg.copy[msg->sg.start]) {
232 msg->data_end = NULL;
234 msg->data = sg_virt(sge);
235 msg->data_end = msg->data + sge->length;
239 static inline void sk_msg_page_add(struct sk_msg *msg, struct page *page,
242 struct scatterlist *sge;
245 sge = sk_msg_elem(msg, msg->sg.end);
246 sg_set_page(sge, page, len, offset);
249 msg->sg.copy[msg->sg.end] = true;
251 sk_msg_iter_next(msg, end);
254 static inline void sk_msg_sg_copy(struct sk_msg *msg, u32 i, bool copy_state)
257 msg->sg.copy[i] = copy_state;
258 sk_msg_iter_var_next(i);
259 if (i == msg->sg.end)
264 static inline void sk_msg_sg_copy_set(struct sk_msg *msg, u32 start)
266 sk_msg_sg_copy(msg, start, true);
269 static inline void sk_msg_sg_copy_clear(struct sk_msg *msg, u32 start)
271 sk_msg_sg_copy(msg, start, false);
274 static inline struct sk_psock *sk_psock(const struct sock *sk)
276 return rcu_dereference_sk_user_data(sk);
279 static inline void sk_psock_queue_msg(struct sk_psock *psock,
282 list_add_tail(&msg->list, &psock->ingress_msg);
285 static inline bool sk_psock_queue_empty(const struct sk_psock *psock)
287 return psock ? list_empty(&psock->ingress_msg) : true;
290 static inline void sk_psock_report_error(struct sk_psock *psock, int err)
292 struct sock *sk = psock->sk;
295 sk->sk_error_report(sk);
298 struct sk_psock *sk_psock_init(struct sock *sk, int node);
300 int sk_psock_init_strp(struct sock *sk, struct sk_psock *psock);
301 void sk_psock_start_strp(struct sock *sk, struct sk_psock *psock);
302 void sk_psock_stop_strp(struct sock *sk, struct sk_psock *psock);
304 int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
307 static inline struct sk_psock_link *sk_psock_init_link(void)
309 return kzalloc(sizeof(struct sk_psock_link),
310 GFP_ATOMIC | __GFP_NOWARN);
313 static inline void sk_psock_free_link(struct sk_psock_link *link)
318 struct sk_psock_link *sk_psock_link_pop(struct sk_psock *psock);
319 #if defined(CONFIG_BPF_STREAM_PARSER)
320 void sk_psock_unlink(struct sock *sk, struct sk_psock_link *link);
322 static inline void sk_psock_unlink(struct sock *sk,
323 struct sk_psock_link *link)
328 void __sk_psock_purge_ingress_msg(struct sk_psock *psock);
330 static inline void sk_psock_cork_free(struct sk_psock *psock)
333 sk_msg_free(psock->sk, psock->cork);
339 static inline void sk_psock_update_proto(struct sock *sk,
340 struct sk_psock *psock,
343 psock->saved_unhash = sk->sk_prot->unhash;
344 psock->saved_close = sk->sk_prot->close;
345 psock->saved_write_space = sk->sk_write_space;
347 psock->sk_proto = sk->sk_prot;
351 static inline void sk_psock_restore_proto(struct sock *sk,
352 struct sk_psock *psock)
354 sk->sk_write_space = psock->saved_write_space;
356 if (psock->sk_proto) {
357 sk->sk_prot = psock->sk_proto;
358 psock->sk_proto = NULL;
362 static inline void sk_psock_set_state(struct sk_psock *psock,
363 enum sk_psock_state_bits bit)
365 set_bit(bit, &psock->state);
368 static inline void sk_psock_clear_state(struct sk_psock *psock,
369 enum sk_psock_state_bits bit)
371 clear_bit(bit, &psock->state);
374 static inline bool sk_psock_test_state(const struct sk_psock *psock,
375 enum sk_psock_state_bits bit)
377 return test_bit(bit, &psock->state);
380 static inline struct sk_psock *sk_psock_get_checked(struct sock *sk)
382 struct sk_psock *psock;
385 psock = sk_psock(sk);
387 if (sk->sk_prot->recvmsg != tcp_bpf_recvmsg) {
388 psock = ERR_PTR(-EBUSY);
392 if (!refcount_inc_not_zero(&psock->refcnt))
393 psock = ERR_PTR(-EBUSY);
400 static inline struct sk_psock *sk_psock_get(struct sock *sk)
402 struct sk_psock *psock;
405 psock = sk_psock(sk);
406 if (psock && !refcount_inc_not_zero(&psock->refcnt))
412 void sk_psock_stop(struct sock *sk, struct sk_psock *psock);
413 void sk_psock_destroy(struct rcu_head *rcu);
414 void sk_psock_drop(struct sock *sk, struct sk_psock *psock);
416 static inline void sk_psock_put(struct sock *sk, struct sk_psock *psock)
418 if (refcount_dec_and_test(&psock->refcnt))
419 sk_psock_drop(sk, psock);
422 static inline void sk_psock_data_ready(struct sock *sk, struct sk_psock *psock)
424 if (psock->parser.enabled)
425 psock->parser.saved_data_ready(sk);
427 sk->sk_data_ready(sk);
430 static inline void psock_set_prog(struct bpf_prog **pprog,
431 struct bpf_prog *prog)
433 prog = xchg(pprog, prog);
438 static inline void psock_progs_drop(struct sk_psock_progs *progs)
440 psock_set_prog(&progs->msg_parser, NULL);
441 psock_set_prog(&progs->skb_parser, NULL);
442 psock_set_prog(&progs->skb_verdict, NULL);
445 #endif /* _LINUX_SKMSG_H */