include/linux/igmp.h - kernel/common.git - Git at Google

 /* SPDX-License-Identifier: GPL-2.0-or-later */
 /*
  *	Linux NET3:	Internet Group Management Protocol  [IGMP]
  *
  *	Authors:
  *		Alan Cox <alan@lxorguk.ukuu.org.uk>
  *
  *	Extended to talk the BSD extended IGMP protocol of mrouted 3.6
  */
 #ifndef _LINUX_IGMP_H
 #define _LINUX_IGMP_H

 #include <linux/skbuff.h>
 #include <linux/timer.h>
 #include <linux/in.h>
 #include <linux/ip.h>
 #include <linux/refcount.h>
 #include <linux/sockptr.h>
 #include <uapi/linux/igmp.h>

 static inline struct igmphdr *igmp_hdr(const struct sk_buff *skb)
 {
 	return (struct igmphdr *)skb_transport_header(skb);
 }

 static inline struct igmpv3_report *
 			igmpv3_report_hdr(const struct sk_buff *skb)
 {
 	return (struct igmpv3_report *)skb_transport_header(skb);
 }

 static inline struct igmpv3_query *
 			igmpv3_query_hdr(const struct sk_buff *skb)
 {
 	return (struct igmpv3_query *)skb_transport_header(skb);
 }

 struct ip_sf_socklist {
 	unsigned int		sl_max;
 	unsigned int		sl_count;
 	struct rcu_head		rcu;
 	__be32			sl_addr[] __counted_by(sl_max);
 };

 #define IP_SFBLOCK	10	/* allocate this many at once */

 /* ip_mc_socklist is real list now. Speed is not argument;
    this list never used in fast path code
  */

 struct ip_mc_socklist {
 	struct ip_mc_socklist __rcu *next_rcu;
 	struct ip_mreqn		multi;
 	unsigned int		sfmode;		/* MCAST_{INCLUDE,EXCLUDE} */
 	struct ip_sf_socklist __rcu	*sflist;
 	struct rcu_head		rcu;
 };

 struct ip_sf_list {
 	struct ip_sf_list	*sf_next;
 	unsigned long		sf_count[2];	/* include/exclude counts */
 	__be32			sf_inaddr;
 	unsigned char		sf_gsresp;	/* include in g & s response? */
 	unsigned char		sf_oldin;	/* change state */
 	unsigned char		sf_crcount;	/* retrans. left to send */
 };

 struct ip_mc_list {
 	struct in_device	*interface;
 	__be32			multiaddr;
 	unsigned int		sfmode;
 	struct ip_sf_list	*sources;
 	struct ip_sf_list	*tomb;
 	unsigned long		sfcount[2];
 	union {
 		struct ip_mc_list *next;
 		struct ip_mc_list __rcu *next_rcu;
 	};
 	struct ip_mc_list __rcu *next_hash;
 	struct timer_list	timer;
 	int			users;
 	refcount_t		refcnt;
 	spinlock_t		lock;
 	char			tm_running;
 	char			reporter;
 	char			unsolicit_count;
 	char			loaded;
 	unsigned char		gsquery;	/* check source marks? */
 	unsigned char		crcount;
 	unsigned long		mca_cstamp;
 	unsigned long		mca_tstamp;
 	struct rcu_head		rcu;
 };

 /* RFC3376, relevant sections:
  *  - 4.1.1. Maximum Response Code
  *  - 4.1.7. QQIC (Querier's Query Interval Code)
  *
  * For both MRC and QQIC, values >= 128 use the same floating-point
  * encoding as follows:
  *
  *  0 1 2 3 4 5 6 7
  * +-+-+-+-+-+-+-+-+
  * |1| exp | mant  |
  * +-+-+-+-+-+-+-+-+
  */
 #define IGMPV3_FP_EXP(value)		(((value) >> 4) & 0x07)
 #define IGMPV3_FP_MAN(value)		((value) & 0x0f)

 /* IGMPv3 floating-point exponential field min threshold */
 #define IGMPV3_EXP_MIN_THRESHOLD	128
 /* IGMPv3 FP max threshold (mant = 0xF, exp = 7) -> 31744 */
 #define IGMPV3_EXP_MAX_THRESHOLD	31744

 /* V3 exponential field encoding */

 /* IGMPv3 MRC/QQIC 8-bit exponential field encode
  *
  * RFC3376, 4.1.1 & 4.1.7. defines only the decoding formula:
  *     MRT/QQI = (mant | 0x10) << (exp + 3)
  *
  * but does NOT define the encoding procedure. To derive exponent:
  *
  * For any value of mantissa and exponent, the decoding formula
  * indicates that the "hidden bit" (0x10) is shifted 4 bits left
  * to sit above the 4-bit mantissa. The RFC again shifts this
  * entire block left by (exp + 3) to reconstruct the value.
  * So, 'hidden bit' is the MSB which is shifted by (4 + exp + 3).
  *
  * Total left shift of the 'hidden bit' = 4 + (exp + 3) = exp + 7.
  * This is the MSB at the 0-based bit position: (exp + 7).
  * Since fls() is 1-based, fls(value) - 1 = exp + 7.
  *
  * Therefore:
  *     exp  = fls(value) - 8
  *     mant = (value >> (exp + 3)) & 0x0F
  *
  * Final encoding formula:
  *     0x80 | (exp << 4) | mant
  *
  * Example (value = 3200):
  *  0               1
  *  0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  * |0 0 0 0 1 1 0 0 1 0 0 0 0 0 0 0| (value = 3200)
  * |        ^-^-mant^ ^..(exp+3)..^| exp = 4, mant = 9
  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  *
  * Encoded:
  *   0x80 | (4 << 4) | 9 = 0xC9
  */
 static inline u8 igmpv3_exp_field_encode(unsigned long value)
 {
 	u8 mc_exp, mc_man;

 	/* MRC/QQIC < 128 is literal */
 	if (value < IGMPV3_EXP_MIN_THRESHOLD)
 		return value;

 	/* Saturate at max representable (mant = 0xF, exp = 7) -> 31744 */
 	if (value >= IGMPV3_EXP_MAX_THRESHOLD)
 		return 0xFF;

 	mc_exp  = fls(value) - 8;
 	mc_man = (value >> (mc_exp + 3)) & 0x0F;

 	return 0x80 | (mc_exp << 4) | mc_man;
 }

 /* Calculate Maximum Response Code from Max Resp Time
  *
  * RFC3376, relevant sections:
  *  - 4.1.1. Maximum Response Code
  *  - 8.3. Query Response Interval
  *
  * MRC represents the encoded form of Max Resp Time (MRT); once
  * decoded, the resulting value is in units of 0.1 seconds (100 ms).
  */
 static inline u8 igmpv3_mrc(unsigned long mrt)
 {
 	return igmpv3_exp_field_encode(mrt);
 }

 /* Calculate Querier's Query Interval Code from Querier's Query Interval
  *
  * RFC3376, relevant sections:
  *  - 4.1.7. QQIC (Querier's Query Interval Code)
  *  - 8.2. Query Interval
  *  - 8.12. Older Version Querier Present Timeout
  *    (the [Query Interval] in the last Query received)
  *
  * QQIC represents the encoded form of Querier's Query Interval (QQI);
  * once decoded, the resulting value is in units of seconds.
  */
 static inline u8 igmpv3_qqic(unsigned long qi)
 {
 	return igmpv3_exp_field_encode(qi);
 }

 /* V3 exponential field decoding */

 /* IGMPv3 MRC/QQIC 8-bit exponential field decode
  *
  * RFC3376, 4.1.1 & 4.1.7. defines the decoding formula:
  *      0 1 2 3 4 5 6 7
  *     +-+-+-+-+-+-+-+-+
  *     |1| exp | mant  |
  *     +-+-+-+-+-+-+-+-+
  * Max Resp Time = (mant | 0x10) << (exp + 3)
  * QQI = (mant | 0x10) << (exp + 3)
  */
 static inline unsigned long igmpv3_exp_field_decode(const u8 code)
 {
 	if (code < IGMPV3_EXP_MIN_THRESHOLD) {
 		return code;
 	} else {
 		unsigned long mc_man, mc_exp;

 		mc_exp = IGMPV3_FP_EXP(code);
 		mc_man = IGMPV3_FP_MAN(code);

 		return (mc_man | 0x10) << (mc_exp + 3);
 	}
 }

 /* Calculate Max Resp Time from Maximum Response Code
  *
  * RFC3376, relevant sections:
  *  - 4.1.1. Maximum Response Code
  *  - 8.3. Query Response Interval
  *
  * After decode, MRC represents the Maximum Response Time (MRT) in
  * units of 0.1 seconds (100 ms).
  */
 static inline unsigned long igmpv3_mrt(const struct igmpv3_query *ih3)
 {
 	return igmpv3_exp_field_decode(ih3->code);
 }

 /* Calculate Querier's Query Interval from Querier's Query Interval Code
  *
  * RFC3376, relevant sections:
  *  - 4.1.7. QQIC (Querier's Query Interval Code)
  *  - 8.2. Query Interval
  *  - 8.12. Older Version Querier Present Timeout
  *    (the [Query Interval] in the last Query received)
  *
  * After decode, QQIC represents the Querier's Query Interval in units
  * of seconds.
  */
 static inline unsigned long igmpv3_qqi(const struct igmpv3_query *ih3)
 {
 	return igmpv3_exp_field_decode(ih3->qqic);
 }

 static inline int ip_mc_may_pull(struct sk_buff *skb, unsigned int len)
 {
 	if (skb_transport_offset(skb) + ip_transport_len(skb) < len)
 		return 0;

 	return pskb_may_pull(skb, len);
 }

 extern int ip_check_mc_rcu(struct in_device *dev, __be32 mc_addr, __be32 src_addr, u8 proto);
 extern int igmp_rcv(struct sk_buff *);
 extern int ip_mc_join_group(struct sock *sk, struct ip_mreqn *imr);
 extern int ip_mc_join_group_ssm(struct sock *sk, struct ip_mreqn *imr,
 				unsigned int mode);
 extern int ip_mc_leave_group(struct sock *sk, struct ip_mreqn *imr);
 extern void ip_mc_drop_socket(struct sock *sk);
 extern int ip_mc_source(int add, int omode, struct sock *sk,
 		struct ip_mreq_source *mreqs, int ifindex);
 extern int ip_mc_msfilter(struct sock *sk, struct ip_msfilter *msf,int ifindex);
 extern int ip_mc_msfget(struct sock *sk, struct ip_msfilter *msf,
 			sockptr_t optval, sockptr_t optlen);
 extern int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
 			sockptr_t optval, size_t offset);
 extern int ip_mc_sf_allow(const struct sock *sk, __be32 local, __be32 rmt,
 			  int dif, int sdif);
 extern void ip_mc_init_dev(struct in_device *);
 extern void ip_mc_destroy_dev(struct in_device *);
 extern void ip_mc_up(struct in_device *);
 extern void ip_mc_down(struct in_device *);
 extern void ip_mc_unmap(struct in_device *);
 extern void ip_mc_remap(struct in_device *);
 extern void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp);
 static inline void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
 {
 	return __ip_mc_dec_group(in_dev, addr, GFP_KERNEL);
 }
 extern void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
 			      gfp_t gfp);
 extern void ip_mc_inc_group(struct in_device *in_dev, __be32 addr);
 int ip_mc_check_igmp(struct sk_buff *skb);

 #endif
	/* SPDX-License-Identifier: GPL-2.0-or-later */
	/*
	* Linux NET3: Internet Group Management Protocol [IGMP]
	*
	* Authors:
	* Alan Cox <alan@lxorguk.ukuu.org.uk>
	*
	* Extended to talk the BSD extended IGMP protocol of mrouted 3.6
	*/
	#ifndef _LINUX_IGMP_H
	#define _LINUX_IGMP_H

	#include <linux/skbuff.h>
	#include <linux/timer.h>
	#include <linux/in.h>
	#include <linux/ip.h>
	#include <linux/refcount.h>
	#include <linux/sockptr.h>
	#include <uapi/linux/igmp.h>

	static inline struct igmphdr igmp_hdr(const struct sk_buff skb)
	{
	return (struct igmphdr *)skb_transport_header(skb);
	}

	static inline struct igmpv3_report *
	igmpv3_report_hdr(const struct sk_buff *skb)
	{
	return (struct igmpv3_report *)skb_transport_header(skb);
	}

	static inline struct igmpv3_query *
	igmpv3_query_hdr(const struct sk_buff *skb)
	{
	return (struct igmpv3_query *)skb_transport_header(skb);
	}

	struct ip_sf_socklist {
	unsigned int sl_max;
	unsigned int sl_count;
	struct rcu_head rcu;
	__be32 sl_addr[] __counted_by(sl_max);
	};

	#define IP_SFBLOCK 10 /* allocate this many at once */

	/* ip_mc_socklist is real list now. Speed is not argument;
	this list never used in fast path code
	*/

	struct ip_mc_socklist {
	struct ip_mc_socklist __rcu *next_rcu;
	struct ip_mreqn multi;
	unsigned int sfmode; /* MCAST_{INCLUDE,EXCLUDE} */
	struct ip_sf_socklist __rcu *sflist;
	struct rcu_head rcu;
	};

	struct ip_sf_list {
	struct ip_sf_list *sf_next;
	unsigned long sf_count[2]; /* include/exclude counts */
	__be32 sf_inaddr;
	unsigned char sf_gsresp; /* include in g & s response? */
	unsigned char sf_oldin; /* change state */
	unsigned char sf_crcount; /* retrans. left to send */
	};

	struct ip_mc_list {
	struct in_device *interface;
	__be32 multiaddr;
	unsigned int sfmode;
	struct ip_sf_list *sources;
	struct ip_sf_list *tomb;
	unsigned long sfcount[2];
	union {
	struct ip_mc_list *next;
	struct ip_mc_list __rcu *next_rcu;
	};
	struct ip_mc_list __rcu *next_hash;
	struct timer_list timer;
	int users;
	refcount_t refcnt;
	spinlock_t lock;
	char tm_running;
	char reporter;
	char unsolicit_count;
	char loaded;
	unsigned char gsquery; /* check source marks? */
	unsigned char crcount;
	unsigned long mca_cstamp;
	unsigned long mca_tstamp;
	struct rcu_head rcu;
	};

	/* RFC3376, relevant sections:
	* - 4.1.1. Maximum Response Code
	* - 4.1.7. QQIC (Querier's Query Interval Code)
	*
	* For both MRC and QQIC, values >= 128 use the same floating-point
	* encoding as follows:
	*
	* 0 1 2 3 4 5 6 7
	* +-+-+-+-+-+-+-+-+
	* \|1\| exp \| mant \|
	* +-+-+-+-+-+-+-+-+
	*/
	#define IGMPV3_FP_EXP(value) (((value) >> 4) & 0x07)
	#define IGMPV3_FP_MAN(value) ((value) & 0x0f)

	/* IGMPv3 floating-point exponential field min threshold */
	#define IGMPV3_EXP_MIN_THRESHOLD 128
	/* IGMPv3 FP max threshold (mant = 0xF, exp = 7) -> 31744 */
	#define IGMPV3_EXP_MAX_THRESHOLD 31744

	/* V3 exponential field encoding */

	/* IGMPv3 MRC/QQIC 8-bit exponential field encode
	*
	* RFC3376, 4.1.1 & 4.1.7. defines only the decoding formula:
	* MRT/QQI = (mant \| 0x10) << (exp + 3)
	*
	* but does NOT define the encoding procedure. To derive exponent:
	*
	* For any value of mantissa and exponent, the decoding formula
	* indicates that the "hidden bit" (0x10) is shifted 4 bits left
	* to sit above the 4-bit mantissa. The RFC again shifts this
	* entire block left by (exp + 3) to reconstruct the value.
	* So, 'hidden bit' is the MSB which is shifted by (4 + exp + 3).
	*
	* Total left shift of the 'hidden bit' = 4 + (exp + 3) = exp + 7.
	* This is the MSB at the 0-based bit position: (exp + 7).
	* Since fls() is 1-based, fls(value) - 1 = exp + 7.
	*
	* Therefore:
	* exp = fls(value) - 8
	* mant = (value >> (exp + 3)) & 0x0F
	*
	* Final encoding formula:
	* 0x80 \| (exp << 4) \| mant
	*
	* Example (value = 3200):
	* 0 1
	* 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	* \|0 0 0 0 1 1 0 0 1 0 0 0 0 0 0 0\| (value = 3200)
	* \| ^-^-mant^ ^..(exp+3)..^\| exp = 4, mant = 9
	* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
	*
	* Encoded:
	* 0x80 \| (4 << 4) \| 9 = 0xC9
	*/
	static inline u8 igmpv3_exp_field_encode(unsigned long value)
	{
	u8 mc_exp, mc_man;

	/* MRC/QQIC < 128 is literal */
	if (value < IGMPV3_EXP_MIN_THRESHOLD)
	return value;

	/* Saturate at max representable (mant = 0xF, exp = 7) -> 31744 */
	if (value >= IGMPV3_EXP_MAX_THRESHOLD)
	return 0xFF;

	mc_exp = fls(value) - 8;
	mc_man = (value >> (mc_exp + 3)) & 0x0F;

	return 0x80 \| (mc_exp << 4) \| mc_man;
	}

	/* Calculate Maximum Response Code from Max Resp Time
	*
	* RFC3376, relevant sections:
	* - 4.1.1. Maximum Response Code
	* - 8.3. Query Response Interval
	*
	* MRC represents the encoded form of Max Resp Time (MRT); once
	* decoded, the resulting value is in units of 0.1 seconds (100 ms).
	*/
	static inline u8 igmpv3_mrc(unsigned long mrt)
	{
	return igmpv3_exp_field_encode(mrt);
	}

	/* Calculate Querier's Query Interval Code from Querier's Query Interval
	*
	* RFC3376, relevant sections:
	* - 4.1.7. QQIC (Querier's Query Interval Code)
	* - 8.2. Query Interval
	* - 8.12. Older Version Querier Present Timeout
	* (the [Query Interval] in the last Query received)
	*
	* QQIC represents the encoded form of Querier's Query Interval (QQI);
	* once decoded, the resulting value is in units of seconds.
	*/
	static inline u8 igmpv3_qqic(unsigned long qi)
	{
	return igmpv3_exp_field_encode(qi);
	}

	/* V3 exponential field decoding */

	/* IGMPv3 MRC/QQIC 8-bit exponential field decode
	*
	* RFC3376, 4.1.1 & 4.1.7. defines the decoding formula:
	* 0 1 2 3 4 5 6 7
	* +-+-+-+-+-+-+-+-+
	* \|1\| exp \| mant \|
	* +-+-+-+-+-+-+-+-+
	* Max Resp Time = (mant \| 0x10) << (exp + 3)
	* QQI = (mant \| 0x10) << (exp + 3)
	*/
	static inline unsigned long igmpv3_exp_field_decode(const u8 code)
	{
	if (code < IGMPV3_EXP_MIN_THRESHOLD) {
	return code;
	} else {
	unsigned long mc_man, mc_exp;

	mc_exp = IGMPV3_FP_EXP(code);
	mc_man = IGMPV3_FP_MAN(code);

	return (mc_man \| 0x10) << (mc_exp + 3);
	}
	}

	/* Calculate Max Resp Time from Maximum Response Code
	*
	* RFC3376, relevant sections:
	* - 4.1.1. Maximum Response Code
	* - 8.3. Query Response Interval
	*
	* After decode, MRC represents the Maximum Response Time (MRT) in
	* units of 0.1 seconds (100 ms).
	*/
	static inline unsigned long igmpv3_mrt(const struct igmpv3_query *ih3)
	{
	return igmpv3_exp_field_decode(ih3->code);
	}

	/* Calculate Querier's Query Interval from Querier's Query Interval Code
	*
	* RFC3376, relevant sections:
	* - 4.1.7. QQIC (Querier's Query Interval Code)
	* - 8.2. Query Interval
	* - 8.12. Older Version Querier Present Timeout
	* (the [Query Interval] in the last Query received)
	*
	* After decode, QQIC represents the Querier's Query Interval in units
	* of seconds.
	*/
	static inline unsigned long igmpv3_qqi(const struct igmpv3_query *ih3)
	{
	return igmpv3_exp_field_decode(ih3->qqic);
	}

	static inline int ip_mc_may_pull(struct sk_buff *skb, unsigned int len)
	{
	if (skb_transport_offset(skb) + ip_transport_len(skb) < len)
	return 0;

	return pskb_may_pull(skb, len);
	}

	extern int ip_check_mc_rcu(struct in_device *dev, __be32 mc_addr, __be32 src_addr, u8 proto);
	extern int igmp_rcv(struct sk_buff *);
	extern int ip_mc_join_group(struct sock sk, struct ip_mreqn imr);
	extern int ip_mc_join_group_ssm(struct sock sk, struct ip_mreqn imr,
	unsigned int mode);
	extern int ip_mc_leave_group(struct sock sk, struct ip_mreqn imr);
	extern void ip_mc_drop_socket(struct sock *sk);
	extern int ip_mc_source(int add, int omode, struct sock *sk,
	struct ip_mreq_source *mreqs, int ifindex);
	extern int ip_mc_msfilter(struct sock sk, struct ip_msfilter msf,int ifindex);
	extern int ip_mc_msfget(struct sock sk, struct ip_msfilter msf,
	sockptr_t optval, sockptr_t optlen);
	extern int ip_mc_gsfget(struct sock sk, struct group_filter gsf,
	sockptr_t optval, size_t offset);
	extern int ip_mc_sf_allow(const struct sock *sk, __be32 local, __be32 rmt,
	int dif, int sdif);
	extern void ip_mc_init_dev(struct in_device *);
	extern void ip_mc_destroy_dev(struct in_device *);
	extern void ip_mc_up(struct in_device *);
	extern void ip_mc_down(struct in_device *);
	extern void ip_mc_unmap(struct in_device *);
	extern void ip_mc_remap(struct in_device *);
	extern void __ip_mc_dec_group(struct in_device *in_dev, __be32 addr, gfp_t gfp);
	static inline void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
	{
	return __ip_mc_dec_group(in_dev, addr, GFP_KERNEL);
	}
	extern void __ip_mc_inc_group(struct in_device *in_dev, __be32 addr,
	gfp_t gfp);
	extern void ip_mc_inc_group(struct in_device *in_dev, __be32 addr);
	int ip_mc_check_igmp(struct sk_buff *skb);

	#endif