Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * Stream Parser
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) #include <linux/bpf.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/errqueue.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/file.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/in.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <linux/net.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include <linux/netdevice.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) #include <linux/poll.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) #include <linux/rculist.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #include <linux/skbuff.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #include <linux/socket.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #include <linux/uaccess.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) #include <linux/workqueue.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) #include <net/strparser.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) #include <net/netns/generic.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) #include <net/sock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) static struct workqueue_struct *strp_wq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) static inline struct _strp_msg *_strp_msg(struct sk_buff *skb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 	return (struct _strp_msg *)((void *)skb->cb +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 		offsetof(struct sk_skb_cb, strp));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) /* Lower lock held */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) static void strp_abort_strp(struct strparser *strp, int err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	/* Unrecoverable error in receive */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	cancel_delayed_work(&strp->msg_timer_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	if (strp->stopped)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	strp->stopped = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	if (strp->sk) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 		struct sock *sk = strp->sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 		/* Report an error on the lower socket */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 		sk->sk_err = -err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 		sk->sk_error_report(sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) static void strp_start_timer(struct strparser *strp, long timeo)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	if (timeo && timeo != LONG_MAX)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 		mod_delayed_work(strp_wq, &strp->msg_timer_work, timeo);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) /* Lower lock held */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) static void strp_parser_err(struct strparser *strp, int err,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 			    read_descriptor_t *desc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	desc->error = err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 	kfree_skb(strp->skb_head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 	strp->skb_head = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	strp->cb.abort_parser(strp, err);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) static inline int strp_peek_len(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 	if (strp->sk) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 		struct socket *sock = strp->sk->sk_socket;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 		return sock->ops->peek_len(sock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	/* If we don't have an associated socket there's nothing to peek.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 	 * Return int max to avoid stopping the strparser.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	return INT_MAX;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) /* Lower socket lock held */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) static int __strp_recv(read_descriptor_t *desc, struct sk_buff *orig_skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 		       unsigned int orig_offset, size_t orig_len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 		       size_t max_msg_size, long timeo)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	struct strparser *strp = (struct strparser *)desc->arg.data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	struct _strp_msg *stm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	struct sk_buff *head, *skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	size_t eaten = 0, cand_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 	ssize_t extra;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 	int err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	bool cloned_orig = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 	if (strp->paused)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 		return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 	head = strp->skb_head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 	if (head) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 		/* Message already in progress */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 		if (unlikely(orig_offset)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 			/* Getting data with a non-zero offset when a message is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 			 * in progress is not expected. If it does happen, we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 			 * need to clone and pull since we can't deal with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 			 * offsets in the skbs for a message expect in the head.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 			 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 			orig_skb = skb_clone(orig_skb, GFP_ATOMIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 			if (!orig_skb) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 				STRP_STATS_INCR(strp->stats.mem_fail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 				desc->error = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 				return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 			}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 			if (!pskb_pull(orig_skb, orig_offset)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 				STRP_STATS_INCR(strp->stats.mem_fail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 				kfree_skb(orig_skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 				desc->error = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 				return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 			}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 			cloned_orig = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 			orig_offset = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 		if (!strp->skb_nextp) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 			/* We are going to append to the frags_list of head.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 			 * Need to unshare the frag_list.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 			 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 			err = skb_unclone(head, GFP_ATOMIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 			if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 				STRP_STATS_INCR(strp->stats.mem_fail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 				desc->error = err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 				return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 			}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 			if (unlikely(skb_shinfo(head)->frag_list)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 				/* We can't append to an sk_buff that already
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 				 * has a frag_list. We create a new head, point
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 				 * the frag_list of that to the old head, and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 				 * then are able to use the old head->next for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 				 * appending to the message.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 				 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 				if (WARN_ON(head->next)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 					desc->error = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 					return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 				}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 				skb = alloc_skb_for_msg(head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 				if (!skb) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 					STRP_STATS_INCR(strp->stats.mem_fail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 					desc->error = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 					return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 				}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 				strp->skb_nextp = &head->next;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 				strp->skb_head = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 				head = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 			} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 				strp->skb_nextp =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 				    &skb_shinfo(head)->frag_list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 			}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 	while (eaten < orig_len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 		/* Always clone since we will consume something */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 		skb = skb_clone(orig_skb, GFP_ATOMIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 		if (!skb) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 			STRP_STATS_INCR(strp->stats.mem_fail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 			desc->error = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 		cand_len = orig_len - eaten;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 		head = strp->skb_head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 		if (!head) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 			head = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 			strp->skb_head = head;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 			/* Will set skb_nextp on next packet if needed */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 			strp->skb_nextp = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 			stm = _strp_msg(head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 			memset(stm, 0, sizeof(*stm));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 			stm->strp.offset = orig_offset + eaten;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 		} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 			/* Unclone if we are appending to an skb that we
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 			 * already share a frag_list with.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 			 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 			if (skb_has_frag_list(skb)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 				err = skb_unclone(skb, GFP_ATOMIC);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 				if (err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 					STRP_STATS_INCR(strp->stats.mem_fail);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 					desc->error = err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 					break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 				}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 			}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 			stm = _strp_msg(head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 			*strp->skb_nextp = skb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 			strp->skb_nextp = &skb->next;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 			head->data_len += skb->len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 			head->len += skb->len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 			head->truesize += skb->truesize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) 		if (!stm->strp.full_len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 			ssize_t len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 			len = (*strp->cb.parse_msg)(strp, head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 			if (!len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 				/* Need more header to determine length */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 				if (!stm->accum_len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 					/* Start RX timer for new message */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 					strp_start_timer(strp, timeo);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 				}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 				stm->accum_len += cand_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) 				eaten += cand_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 				STRP_STATS_INCR(strp->stats.need_more_hdr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 				WARN_ON(eaten != orig_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 				break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 			} else if (len < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 				if (len == -ESTRPIPE && stm->accum_len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 					len = -ENODATA;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 					strp->unrecov_intr = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 				} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 					strp->interrupted = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 				}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) 				strp_parser_err(strp, len, desc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 				break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 			} else if (len > max_msg_size) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) 				/* Message length exceeds maximum allowed */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 				STRP_STATS_INCR(strp->stats.msg_too_big);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) 				strp_parser_err(strp, -EMSGSIZE, desc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 				break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 			} else if (len <= (ssize_t)head->len -
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) 					  skb->len - stm->strp.offset) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 				/* Length must be into new skb (and also
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) 				 * greater than zero)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) 				 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 				STRP_STATS_INCR(strp->stats.bad_hdr_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 				strp_parser_err(strp, -EPROTO, desc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) 				break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 			}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) 			stm->strp.full_len = len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 		extra = (ssize_t)(stm->accum_len + cand_len) -
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) 			stm->strp.full_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) 		if (extra < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) 			/* Message not complete yet. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) 			if (stm->strp.full_len - stm->accum_len >
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) 			    strp_peek_len(strp)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) 				/* Don't have the whole message in the socket
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) 				 * buffer. Set strp->need_bytes to wait for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) 				 * the rest of the message. Also, set "early
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 				 * eaten" since we've already buffered the skb
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) 				 * but don't consume yet per strp_read_sock.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 				 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) 				if (!stm->accum_len) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 					/* Start RX timer for new message */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) 					strp_start_timer(strp, timeo);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) 				}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) 				stm->accum_len += cand_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) 				eaten += cand_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) 				strp->need_bytes = stm->strp.full_len -
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) 						       stm->accum_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) 				STRP_STATS_ADD(strp->stats.bytes, cand_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) 				desc->count = 0; /* Stop reading socket */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) 				break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) 			}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) 			stm->accum_len += cand_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) 			eaten += cand_len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) 			WARN_ON(eaten != orig_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) 		/* Positive extra indicates more bytes than needed for the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) 		 * message
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 		 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) 		WARN_ON(extra > cand_len);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) 		eaten += (cand_len - extra);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) 		/* Hurray, we have a new message! */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) 		cancel_delayed_work(&strp->msg_timer_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) 		strp->skb_head = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) 		strp->need_bytes = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) 		STRP_STATS_INCR(strp->stats.msgs);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) 		/* Give skb to upper layer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) 		strp->cb.rcv_msg(strp, head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) 		if (unlikely(strp->paused)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) 			/* Upper layer paused strp */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) 	if (cloned_orig)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) 		kfree_skb(orig_skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) 	STRP_STATS_ADD(strp->stats.bytes, eaten);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) 	return eaten;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) int strp_process(struct strparser *strp, struct sk_buff *orig_skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) 		 unsigned int orig_offset, size_t orig_len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) 		 size_t max_msg_size, long timeo)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) 	read_descriptor_t desc; /* Dummy arg to strp_recv */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) 	desc.arg.data = strp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) 	return __strp_recv(&desc, orig_skb, orig_offset, orig_len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) 			   max_msg_size, timeo);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) EXPORT_SYMBOL_GPL(strp_process);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) static int strp_recv(read_descriptor_t *desc, struct sk_buff *orig_skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) 		     unsigned int orig_offset, size_t orig_len)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) 	struct strparser *strp = (struct strparser *)desc->arg.data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) 	return __strp_recv(desc, orig_skb, orig_offset, orig_len,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) 			   strp->sk->sk_rcvbuf, strp->sk->sk_rcvtimeo);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) static int default_read_sock_done(struct strparser *strp, int err)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) /* Called with lock held on lower socket */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) static int strp_read_sock(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) 	struct socket *sock = strp->sk->sk_socket;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) 	read_descriptor_t desc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) 	if (unlikely(!sock || !sock->ops || !sock->ops->read_sock))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) 		return -EBUSY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) 	desc.arg.data = strp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) 	desc.error = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) 	desc.count = 1; /* give more than one skb per call */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) 	/* sk should be locked here, so okay to do read_sock */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) 	sock->ops->read_sock(strp->sk, &desc, strp_recv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) 	desc.error = strp->cb.read_sock_done(strp, desc.error);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) 	return desc.error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) /* Lower sock lock held */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) void strp_data_ready(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) 	if (unlikely(strp->stopped) || strp->paused)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) 	/* This check is needed to synchronize with do_strp_work.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) 	 * do_strp_work acquires a process lock (lock_sock) whereas
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) 	 * the lock held here is bh_lock_sock. The two locks can be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) 	 * held by different threads at the same time, but bh_lock_sock
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) 	 * allows a thread in BH context to safely check if the process
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) 	 * lock is held. In this case, if the lock is held, queue work.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) 	if (sock_owned_by_user_nocheck(strp->sk)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) 		queue_work(strp_wq, &strp->work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) 	if (strp->need_bytes) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) 		if (strp_peek_len(strp) < strp->need_bytes)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) 			return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) 	if (strp_read_sock(strp) == -ENOMEM)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) 		queue_work(strp_wq, &strp->work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) EXPORT_SYMBOL_GPL(strp_data_ready);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) static void do_strp_work(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) 	/* We need the read lock to synchronize with strp_data_ready. We
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) 	 * need the socket lock for calling strp_read_sock.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) 	strp->cb.lock(strp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) 	if (unlikely(strp->stopped))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) 	if (strp->paused)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) 	if (strp_read_sock(strp) == -ENOMEM)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) 		queue_work(strp_wq, &strp->work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) 	strp->cb.unlock(strp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) static void strp_work(struct work_struct *w)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) 	do_strp_work(container_of(w, struct strparser, work));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) static void strp_msg_timeout(struct work_struct *w)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) 	struct strparser *strp = container_of(w, struct strparser,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) 					      msg_timer_work.work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) 	/* Message assembly timed out */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) 	STRP_STATS_INCR(strp->stats.msg_timeouts);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) 	strp->cb.lock(strp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426) 	strp->cb.abort_parser(strp, -ETIMEDOUT);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) 	strp->cb.unlock(strp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) static void strp_sock_lock(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432) 	lock_sock(strp->sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) static void strp_sock_unlock(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) 	release_sock(strp->sk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440) int strp_init(struct strparser *strp, struct sock *sk,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) 	      const struct strp_callbacks *cb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) 	if (!cb || !cb->rcv_msg || !cb->parse_msg)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447) 	/* The sk (sock) arg determines the mode of the stream parser.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) 	 *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) 	 * If the sock is set then the strparser is in receive callback mode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) 	 * The upper layer calls strp_data_ready to kick receive processing
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451) 	 * and strparser calls the read_sock function on the socket to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) 	 * get packets.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) 	 *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454) 	 * If the sock is not set then the strparser is in general mode.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) 	 * The upper layer calls strp_process for each skb to be parsed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) 	 */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458) 	if (!sk) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) 		if (!cb->lock || !cb->unlock)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) 			return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) 	memset(strp, 0, sizeof(*strp));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) 	strp->sk = sk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) 	strp->cb.lock = cb->lock ? : strp_sock_lock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) 	strp->cb.unlock = cb->unlock ? : strp_sock_unlock;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) 	strp->cb.rcv_msg = cb->rcv_msg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) 	strp->cb.parse_msg = cb->parse_msg;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) 	strp->cb.read_sock_done = cb->read_sock_done ? : default_read_sock_done;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472) 	strp->cb.abort_parser = cb->abort_parser ? : strp_abort_strp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) 	INIT_DELAYED_WORK(&strp->msg_timer_work, strp_msg_timeout);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) 	INIT_WORK(&strp->work, strp_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) EXPORT_SYMBOL_GPL(strp_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481) /* Sock process lock held (lock_sock) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) void __strp_unpause(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) 	strp->paused = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) 	if (strp->need_bytes) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) 		if (strp_peek_len(strp) < strp->need_bytes)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) 			return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) 	strp_read_sock(strp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) EXPORT_SYMBOL_GPL(__strp_unpause);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) void strp_unpause(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) 	strp->paused = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) 	/* Sync setting paused with RX work */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) 	smp_mb();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) 	queue_work(strp_wq, &strp->work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) EXPORT_SYMBOL_GPL(strp_unpause);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) /* strp must already be stopped so that strp_recv will no longer be called.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506)  * Note that strp_done is not called with the lower socket held.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) void strp_done(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) 	WARN_ON(!strp->stopped);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512) 	cancel_delayed_work_sync(&strp->msg_timer_work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) 	cancel_work_sync(&strp->work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) 	if (strp->skb_head) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516) 		kfree_skb(strp->skb_head);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) 		strp->skb_head = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) EXPORT_SYMBOL_GPL(strp_done);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) void strp_stop(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) 	strp->stopped = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526) EXPORT_SYMBOL_GPL(strp_stop);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) void strp_check_rcv(struct strparser *strp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530) 	queue_work(strp_wq, &strp->work);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) EXPORT_SYMBOL_GPL(strp_check_rcv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) static int __init strp_dev_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) 	strp_wq = create_singlethread_workqueue("kstrp");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) 	if (unlikely(!strp_wq))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542) device_initcall(strp_dev_init);