 276bdb82de
			
		
	
	
	276bdb82de
	
	
	
		
			
			ccid_hc_rx_getsockopt() and ccid_hc_tx_getsockopt() might be called with a NULL ccid pointer leading to a NULL pointer dereference. This could lead to a privilege escalation if the attacker is able to map page 0 and prepare it with a fake ccid_ops pointer. Signed-off-by: Mathias Krause <minipli@googlemail.com> Cc: Gerrit Renker <gerrit@erg.abdn.ac.uk> Cc: stable@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
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			C
		
	
	
	
	
	
			
		
		
	
	
			265 lines
		
	
	
	
		
			8.8 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef _CCID_H
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| #define _CCID_H
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| /*
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|  *  net/dccp/ccid.h
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|  *
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|  *  An implementation of the DCCP protocol
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|  *  Arnaldo Carvalho de Melo <acme@conectiva.com.br>
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|  *
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|  *  CCID infrastructure
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|  *
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|  *	This program is free software; you can redistribute it and/or modify it
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|  *	under the terms of the GNU General Public License version 2 as
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|  *	published by the Free Software Foundation.
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|  */
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| 
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| #include <net/sock.h>
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| #include <linux/compiler.h>
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| #include <linux/dccp.h>
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| #include <linux/list.h>
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| #include <linux/module.h>
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| 
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| /* maximum value for a CCID (RFC 4340, 19.5) */
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| #define CCID_MAX		255
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| #define CCID_SLAB_NAME_LENGTH	32
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| 
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| struct tcp_info;
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| 
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| /**
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|  *  struct ccid_operations  -  Interface to Congestion-Control Infrastructure
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|  *
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|  *  @ccid_id: numerical CCID ID (up to %CCID_MAX, cf. table 5 in RFC 4340, 10.)
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|  *  @ccid_ccmps: the CCMPS including network/transport headers (0 when disabled)
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|  *  @ccid_name: alphabetical identifier string for @ccid_id
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|  *  @ccid_hc_{r,t}x_slab: memory pool for the receiver/sender half-connection
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|  *  @ccid_hc_{r,t}x_obj_size: size of the receiver/sender half-connection socket
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|  *
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|  *  @ccid_hc_{r,t}x_init: CCID-specific initialisation routine (before startup)
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|  *  @ccid_hc_{r,t}x_exit: CCID-specific cleanup routine (before destruction)
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|  *  @ccid_hc_rx_packet_recv: implements the HC-receiver side
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|  *  @ccid_hc_{r,t}x_parse_options: parsing routine for CCID/HC-specific options
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|  *  @ccid_hc_{r,t}x_insert_options: insert routine for CCID/HC-specific options
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|  *  @ccid_hc_tx_packet_recv: implements feedback processing for the HC-sender
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|  *  @ccid_hc_tx_send_packet: implements the sending part of the HC-sender
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|  *  @ccid_hc_tx_packet_sent: does accounting for packets in flight by HC-sender
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|  *  @ccid_hc_{r,t}x_get_info: INET_DIAG information for HC-receiver/sender
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|  *  @ccid_hc_{r,t}x_getsockopt: socket options specific to HC-receiver/sender
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|  */
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| struct ccid_operations {
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| 	unsigned char		ccid_id;
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| 	__u32			ccid_ccmps;
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| 	const char		*ccid_name;
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| 	struct kmem_cache	*ccid_hc_rx_slab,
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| 				*ccid_hc_tx_slab;
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| 	char			ccid_hc_rx_slab_name[CCID_SLAB_NAME_LENGTH];
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| 	char			ccid_hc_tx_slab_name[CCID_SLAB_NAME_LENGTH];
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| 	__u32			ccid_hc_rx_obj_size,
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| 				ccid_hc_tx_obj_size;
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| 	/* Interface Routines */
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| 	int		(*ccid_hc_rx_init)(struct ccid *ccid, struct sock *sk);
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| 	int		(*ccid_hc_tx_init)(struct ccid *ccid, struct sock *sk);
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| 	void		(*ccid_hc_rx_exit)(struct sock *sk);
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| 	void		(*ccid_hc_tx_exit)(struct sock *sk);
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| 	void		(*ccid_hc_rx_packet_recv)(struct sock *sk,
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| 						  struct sk_buff *skb);
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| 	int		(*ccid_hc_rx_parse_options)(struct sock *sk, u8 pkt,
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| 						    u8 opt, u8 *val, u8 len);
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| 	int		(*ccid_hc_rx_insert_options)(struct sock *sk,
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| 						     struct sk_buff *skb);
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| 	void		(*ccid_hc_tx_packet_recv)(struct sock *sk,
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| 						  struct sk_buff *skb);
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| 	int		(*ccid_hc_tx_parse_options)(struct sock *sk, u8 pkt,
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| 						    u8 opt, u8 *val, u8 len);
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| 	int		(*ccid_hc_tx_send_packet)(struct sock *sk,
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| 						  struct sk_buff *skb);
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| 	void		(*ccid_hc_tx_packet_sent)(struct sock *sk,
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| 						  unsigned int len);
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| 	void		(*ccid_hc_rx_get_info)(struct sock *sk,
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| 					       struct tcp_info *info);
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| 	void		(*ccid_hc_tx_get_info)(struct sock *sk,
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| 					       struct tcp_info *info);
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| 	int		(*ccid_hc_rx_getsockopt)(struct sock *sk,
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| 						 const int optname, int len,
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| 						 u32 __user *optval,
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| 						 int __user *optlen);
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| 	int		(*ccid_hc_tx_getsockopt)(struct sock *sk,
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| 						 const int optname, int len,
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| 						 u32 __user *optval,
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| 						 int __user *optlen);
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| };
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| 
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| extern struct ccid_operations ccid2_ops;
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| #ifdef CONFIG_IP_DCCP_CCID3
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| extern struct ccid_operations ccid3_ops;
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| #endif
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| 
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| extern int  ccid_initialize_builtins(void);
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| extern void ccid_cleanup_builtins(void);
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| 
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| struct ccid {
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| 	struct ccid_operations *ccid_ops;
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| 	char		       ccid_priv[0];
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| };
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| 
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| static inline void *ccid_priv(const struct ccid *ccid)
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| {
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| 	return (void *)ccid->ccid_priv;
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| }
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| 
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| extern bool ccid_support_check(u8 const *ccid_array, u8 array_len);
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| extern int  ccid_get_builtin_ccids(u8 **ccid_array, u8 *array_len);
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| extern int  ccid_getsockopt_builtin_ccids(struct sock *sk, int len,
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| 					  char __user *, int __user *);
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| 
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| extern struct ccid *ccid_new(const u8 id, struct sock *sk, bool rx);
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| 
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| static inline int ccid_get_current_rx_ccid(struct dccp_sock *dp)
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| {
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| 	struct ccid *ccid = dp->dccps_hc_rx_ccid;
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| 
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| 	if (ccid == NULL || ccid->ccid_ops == NULL)
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| 		return -1;
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| 	return ccid->ccid_ops->ccid_id;
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| }
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| 
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| static inline int ccid_get_current_tx_ccid(struct dccp_sock *dp)
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| {
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| 	struct ccid *ccid = dp->dccps_hc_tx_ccid;
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| 
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| 	if (ccid == NULL || ccid->ccid_ops == NULL)
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| 		return -1;
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| 	return ccid->ccid_ops->ccid_id;
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| }
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| 
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| extern void ccid_hc_rx_delete(struct ccid *ccid, struct sock *sk);
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| extern void ccid_hc_tx_delete(struct ccid *ccid, struct sock *sk);
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| 
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| /*
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|  * Congestion control of queued data packets via CCID decision.
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|  *
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|  * The TX CCID performs its congestion-control by indicating whether and when a
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|  * queued packet may be sent, using the return code of ccid_hc_tx_send_packet().
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|  * The following modes are supported via the symbolic constants below:
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|  * - timer-based pacing    (CCID returns a delay value in milliseconds);
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|  * - autonomous dequeueing (CCID internally schedules dccps_xmitlet).
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|  */
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| 
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| enum ccid_dequeueing_decision {
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| 	CCID_PACKET_SEND_AT_ONCE =	 0x00000,  /* "green light": no delay */
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| 	CCID_PACKET_DELAY_MAX =		 0x0FFFF,  /* maximum delay in msecs  */
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| 	CCID_PACKET_DELAY =		 0x10000,  /* CCID msec-delay mode */
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| 	CCID_PACKET_WILL_DEQUEUE_LATER = 0x20000,  /* CCID autonomous mode */
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| 	CCID_PACKET_ERR =		 0xF0000,  /* error condition */
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| };
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| 
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| static inline int ccid_packet_dequeue_eval(const int return_code)
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| {
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| 	if (return_code < 0)
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| 		return CCID_PACKET_ERR;
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| 	if (return_code == 0)
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| 		return CCID_PACKET_SEND_AT_ONCE;
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| 	if (return_code <= CCID_PACKET_DELAY_MAX)
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| 		return CCID_PACKET_DELAY;
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| 	return return_code;
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| }
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| 
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| static inline int ccid_hc_tx_send_packet(struct ccid *ccid, struct sock *sk,
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| 					 struct sk_buff *skb)
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| {
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| 	if (ccid->ccid_ops->ccid_hc_tx_send_packet != NULL)
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| 		return ccid->ccid_ops->ccid_hc_tx_send_packet(sk, skb);
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| 	return CCID_PACKET_SEND_AT_ONCE;
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| }
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| 
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| static inline void ccid_hc_tx_packet_sent(struct ccid *ccid, struct sock *sk,
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| 					  unsigned int len)
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| {
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| 	if (ccid->ccid_ops->ccid_hc_tx_packet_sent != NULL)
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| 		ccid->ccid_ops->ccid_hc_tx_packet_sent(sk, len);
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| }
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| 
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| static inline void ccid_hc_rx_packet_recv(struct ccid *ccid, struct sock *sk,
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| 					  struct sk_buff *skb)
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| {
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| 	if (ccid->ccid_ops->ccid_hc_rx_packet_recv != NULL)
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| 		ccid->ccid_ops->ccid_hc_rx_packet_recv(sk, skb);
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| }
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| 
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| static inline void ccid_hc_tx_packet_recv(struct ccid *ccid, struct sock *sk,
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| 					  struct sk_buff *skb)
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| {
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| 	if (ccid->ccid_ops->ccid_hc_tx_packet_recv != NULL)
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| 		ccid->ccid_ops->ccid_hc_tx_packet_recv(sk, skb);
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| }
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| 
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| /**
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|  * ccid_hc_tx_parse_options  -  Parse CCID-specific options sent by the receiver
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|  * @pkt: type of packet that @opt appears on (RFC 4340, 5.1)
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|  * @opt: the CCID-specific option type (RFC 4340, 5.8 and 10.3)
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|  * @val: value of @opt
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|  * @len: length of @val in bytes
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|  */
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| static inline int ccid_hc_tx_parse_options(struct ccid *ccid, struct sock *sk,
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| 					   u8 pkt, u8 opt, u8 *val, u8 len)
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| {
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| 	if (ccid->ccid_ops->ccid_hc_tx_parse_options == NULL)
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| 		return 0;
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| 	return ccid->ccid_ops->ccid_hc_tx_parse_options(sk, pkt, opt, val, len);
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| }
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| 
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| /**
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|  * ccid_hc_rx_parse_options  -  Parse CCID-specific options sent by the sender
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|  * Arguments are analogous to ccid_hc_tx_parse_options()
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|  */
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| static inline int ccid_hc_rx_parse_options(struct ccid *ccid, struct sock *sk,
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| 					   u8 pkt, u8 opt, u8 *val, u8 len)
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| {
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| 	if (ccid->ccid_ops->ccid_hc_rx_parse_options == NULL)
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| 		return 0;
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| 	return ccid->ccid_ops->ccid_hc_rx_parse_options(sk, pkt, opt, val, len);
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| }
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| 
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| static inline int ccid_hc_rx_insert_options(struct ccid *ccid, struct sock *sk,
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| 					    struct sk_buff *skb)
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| {
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| 	if (ccid->ccid_ops->ccid_hc_rx_insert_options != NULL)
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| 		return ccid->ccid_ops->ccid_hc_rx_insert_options(sk, skb);
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| 	return 0;
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| }
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| 
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| static inline void ccid_hc_rx_get_info(struct ccid *ccid, struct sock *sk,
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| 				       struct tcp_info *info)
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| {
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| 	if (ccid->ccid_ops->ccid_hc_rx_get_info != NULL)
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| 		ccid->ccid_ops->ccid_hc_rx_get_info(sk, info);
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| }
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| 
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| static inline void ccid_hc_tx_get_info(struct ccid *ccid, struct sock *sk,
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| 				       struct tcp_info *info)
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| {
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| 	if (ccid->ccid_ops->ccid_hc_tx_get_info != NULL)
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| 		ccid->ccid_ops->ccid_hc_tx_get_info(sk, info);
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| }
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| 
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| static inline int ccid_hc_rx_getsockopt(struct ccid *ccid, struct sock *sk,
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| 					const int optname, int len,
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| 					u32 __user *optval, int __user *optlen)
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| {
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| 	int rc = -ENOPROTOOPT;
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| 	if (ccid != NULL && ccid->ccid_ops->ccid_hc_rx_getsockopt != NULL)
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| 		rc = ccid->ccid_ops->ccid_hc_rx_getsockopt(sk, optname, len,
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| 						 optval, optlen);
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| 	return rc;
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| }
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| 
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| static inline int ccid_hc_tx_getsockopt(struct ccid *ccid, struct sock *sk,
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| 					const int optname, int len,
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| 					u32 __user *optval, int __user *optlen)
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| {
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| 	int rc = -ENOPROTOOPT;
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| 	if (ccid != NULL && ccid->ccid_ops->ccid_hc_tx_getsockopt != NULL)
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| 		rc = ccid->ccid_ops->ccid_hc_tx_getsockopt(sk, optname, len,
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| 						 optval, optlen);
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| 	return rc;
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| }
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| #endif /* _CCID_H */
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