[mirror_ubuntu-artful-kernel.git] / include / linux / genl_magic_func.h

#ifndef GENL_MAGIC_FUNC_H
#define GENL_MAGIC_FUNC_H

#include <linux/genl_magic_struct.h>

/*
 * Extension of genl attribute validation policies			{{{1
 *									{{{2
 */

/**
 * nla_is_required - return true if this attribute is required
 * @nla: netlink attribute
 */
static inline int nla_is_required(const struct nlattr *nla)
{
        return nla->nla_type & GENLA_F_REQUIRED;
}

/**
 * nla_is_mandatory - return true if understanding this attribute is mandatory
 * @nla: netlink attribute
 * Note: REQUIRED attributes are implicitly MANDATORY as well
 */
static inline int nla_is_mandatory(const struct nlattr *nla)
{
        return nla->nla_type & (GENLA_F_MANDATORY | GENLA_F_REQUIRED);
}

/* Functionality to be integrated into nla_parse(), and validate_nla(),
 * respectively.
 *
 * Enforcing the "mandatory" bit is done here,
 * by rejecting unknown mandatory attributes.
 *
 * Part of enforcing the "required" flag would mean to embed it into
 * nla_policy.type, and extending validate_nla(), which currently does
 * BUG_ON(pt->type > NLA_TYPE_MAX); we have to work on existing kernels,
 * so we cannot do that.  Thats why enforcing "required" is done in the
 * generated assignment functions below. */
static int nla_check_unknown(int maxtype, struct nlattr *head, int len)
{
	struct nlattr *nla;
	int rem;
        nla_for_each_attr(nla, head, len, rem) {
		__u16 type = nla_type(nla);
		if (type > maxtype && nla_is_mandatory(nla))
			return -EOPNOTSUPP;
	}
	return 0;
}

/*
 * Magic: declare tla policy						{{{1
 * Magic: declare nested policies
 *									{{{2
 */
#undef GENL_mc_group
#define GENL_mc_group(group)

#undef GENL_notification
#define GENL_notification(op_name, op_num, mcast_group, tla_list)

#undef GENL_op
#define GENL_op(op_name, op_num, handler, tla_list)

#undef GENL_struct
#define GENL_struct(tag_name, tag_number, s_name, s_fields)		\
	[tag_name] = { .type = NLA_NESTED },

static struct nla_policy CONCAT_(GENL_MAGIC_FAMILY, _tla_nl_policy)[] = {
#include GENL_MAGIC_INCLUDE_FILE
};

#undef GENL_struct
#define GENL_struct(tag_name, tag_number, s_name, s_fields)		\
static struct nla_policy s_name ## _nl_policy[] __read_mostly =		\
{ s_fields };

#undef __field
#define __field(attr_nr, attr_flag, name, nla_type, _type, __get, __put) \
	[__nla_type(attr_nr)] = { .type = nla_type },

#undef __array
#define __array(attr_nr, attr_flag, name, nla_type, _type, maxlen,	\
		__get, __put)						\
	[__nla_type(attr_nr)] = { .type = nla_type,			\
		.len = maxlen - (nla_type == NLA_NUL_STRING) },

#include GENL_MAGIC_INCLUDE_FILE

#ifndef __KERNEL__
#ifndef pr_info
#define pr_info(args...)	fprintf(stderr, args);
#endif
#endif

#ifdef GENL_MAGIC_DEBUG
static void dprint_field(const char *dir, int nla_type,
		const char *name, void *valp)
{
	__u64 val = valp ? *(__u32 *)valp : 1;
	switch (nla_type) {
	case NLA_U8:  val = (__u8)val;
	case NLA_U16: val = (__u16)val;
	case NLA_U32: val = (__u32)val;
		pr_info("%s attr %s: %d 0x%08x\n", dir,
			name, (int)val, (unsigned)val);
		break;
	case NLA_U64:
		val = *(__u64*)valp;
		pr_info("%s attr %s: %lld 0x%08llx\n", dir,
			name, (long long)val, (unsigned long long)val);
		break;
	case NLA_FLAG:
		if (val)
			pr_info("%s attr %s: set\n", dir, name);
		break;
	}
}

static void dprint_array(const char *dir, int nla_type,
		const char *name, const char *val, unsigned len)
{
	switch (nla_type) {
	case NLA_NUL_STRING:
		if (len && val[len-1] == '\0')
			len--;
		pr_info("%s attr %s: [len:%u] '%s'\n", dir, name, len, val);
		break;
	default:
		/* we can always show 4 byte,
		 * thats what nlattr are aligned to. */
		pr_info("%s attr %s: [len:%u] %02x%02x%02x%02x ...\n",
			dir, name, len, val[0], val[1], val[2], val[3]);
	}
}

#define DPRINT_TLA(a, op, b) pr_info("%s %s %s\n", a, op, b);

/* Name is a member field name of the struct s.
 * If s is NULL (only parsing, no copy requested in *_from_attrs()),
 * nla is supposed to point to the attribute containing the information
 * corresponding to that struct member. */
#define DPRINT_FIELD(dir, nla_type, name, s, nla)			\
	do {								\
		if (s)							\
			dprint_field(dir, nla_type, #name, &s->name);	\
		else if (nla)						\
			dprint_field(dir, nla_type, #name,		\
				(nla_type == NLA_FLAG) ? NULL		\
						: nla_data(nla));	\
	} while (0)

#define	DPRINT_ARRAY(dir, nla_type, name, s, nla)			\
	do {								\
		if (s)							\
			dprint_array(dir, nla_type, #name,		\
					s->name, s->name ## _len);	\
		else if (nla)						\
			dprint_array(dir, nla_type, #name,		\
					nla_data(nla), nla_len(nla));	\
	} while (0)
#else
#define DPRINT_TLA(a, op, b) do {} while (0)
#define DPRINT_FIELD(dir, nla_type, name, s, nla) do {} while (0)
#define	DPRINT_ARRAY(dir, nla_type, name, s, nla) do {} while (0)
#endif

/*
 * Magic: provide conversion functions					{{{1
 * populate struct from attribute table:
 *									{{{2
 */

/* processing of generic netlink messages is serialized.
 * use one static buffer for parsing of nested attributes */
static struct nlattr *nested_attr_tb[128];

#ifndef BUILD_BUG_ON
/* Force a compilation error if condition is true */
#define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
/* Force a compilation error if condition is true, but also produce a
   result (of value 0 and type size_t), so the expression can be used
   e.g. in a structure initializer (or where-ever else comma expressions
   aren't permitted). */
#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
#endif

#undef GENL_struct
#define GENL_struct(tag_name, tag_number, s_name, s_fields)		\
/* *_from_attrs functions are static, but potentially unused */		\
static int __ ## s_name ## _from_attrs(struct s_name *s,		\
		struct genl_info *info, bool exclude_invariants)	\
{									\
	const int maxtype = ARRAY_SIZE(s_name ## _nl_policy)-1;		\
	struct nlattr *tla = info->attrs[tag_number];			\
	struct nlattr **ntb = nested_attr_tb;				\
	struct nlattr *nla;						\
	int err;							\
	BUILD_BUG_ON(ARRAY_SIZE(s_name ## _nl_policy) > ARRAY_SIZE(nested_attr_tb));	\
	if (!tla)							\
		return -ENOMSG;						\
	DPRINT_TLA(#s_name, "<=-", #tag_name);				\
	err = nla_parse_nested(ntb, maxtype, tla, s_name ## _nl_policy); \
	if (err)							\
		return err;						\
	err = nla_check_unknown(maxtype, nla_data(tla), nla_len(tla));	\
	if (err)							\
	      return err;						\
									\
	s_fields							\
	return 0;							\
}					__attribute__((unused))		\
static int s_name ## _from_attrs(struct s_name *s,			\
						struct genl_info *info)	\
{									\
	return __ ## s_name ## _from_attrs(s, info, false);		\
}					__attribute__((unused))		\
static int s_name ## _from_attrs_for_change(struct s_name *s,		\
						struct genl_info *info)	\
{									\
	return __ ## s_name ## _from_attrs(s, info, true);		\
}					__attribute__((unused))		\

#define __assign(attr_nr, attr_flag, name, nla_type, type, assignment...)	\
		nla = ntb[__nla_type(attr_nr)];				\
		if (nla) {						\
			if (exclude_invariants && ((attr_flag) & GENLA_F_INVARIANT)) {		\
				pr_info("<< must not change invariant attr: %s\n", #name);	\
				return -EEXIST;				\
			}						\
			assignment;					\
		} else if (exclude_invariants && ((attr_flag) & GENLA_F_INVARIANT)) {		\
			/* attribute missing from payload, */		\
			/* which was expected */			\
		} else if ((attr_flag) & GENLA_F_REQUIRED) {		\
			pr_info("<< missing attr: %s\n", #name);	\
			return -ENOMSG;					\
		}

#undef __field
#define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put)	\
	__assign(attr_nr, attr_flag, name, nla_type, type,		\
			if (s)						\
				s->name = __get(nla);			\
			DPRINT_FIELD("<<", nla_type, name, s, nla))

/* validate_nla() already checked nla_len <= maxlen appropriately. */
#undef __array
#define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \
	__assign(attr_nr, attr_flag, name, nla_type, type,		\
			if (s)						\
				s->name ## _len =			\
					__get(s->name, nla, maxlen);	\
			DPRINT_ARRAY("<<", nla_type, name, s, nla))

#include GENL_MAGIC_INCLUDE_FILE

#undef GENL_struct
#define GENL_struct(tag_name, tag_number, s_name, s_fields)

/*
 * Magic: define op number to op name mapping				{{{1
 *									{{{2
 */
const char *CONCAT_(GENL_MAGIC_FAMILY, _genl_cmd_to_str)(__u8 cmd)
{
	switch (cmd) {
#undef GENL_op
#define GENL_op(op_name, op_num, handler, tla_list)		\
	case op_num: return #op_name;
#include GENL_MAGIC_INCLUDE_FILE
	default:
		     return "unknown";
	}
}

#ifdef __KERNEL__
#include <linux/stringify.h>
/*
 * Magic: define genl_ops						{{{1
 *									{{{2
 */

#undef GENL_op
#define GENL_op(op_name, op_num, handler, tla_list)		\
{								\
	handler							\
	.cmd = op_name,						\
	.policy	= CONCAT_(GENL_MAGIC_FAMILY, _tla_nl_policy),	\
},

#define ZZZ_genl_ops		CONCAT_(GENL_MAGIC_FAMILY, _genl_ops)
static struct genl_ops ZZZ_genl_ops[] __read_mostly = {
#include GENL_MAGIC_INCLUDE_FILE
};

#undef GENL_op
#define GENL_op(op_name, op_num, handler, tla_list)

/*
 * Define the genl_family, multicast groups,				{{{1
 * and provide register/unregister functions.
 *									{{{2
 */
#define ZZZ_genl_family		CONCAT_(GENL_MAGIC_FAMILY, _genl_family)
static struct genl_family ZZZ_genl_family __read_mostly = {
	.id = GENL_ID_GENERATE,
	.name = __stringify(GENL_MAGIC_FAMILY),
	.version = GENL_MAGIC_VERSION,
#ifdef GENL_MAGIC_FAMILY_HDRSZ
	.hdrsize = NLA_ALIGN(GENL_MAGIC_FAMILY_HDRSZ),
#endif
	.maxattr = ARRAY_SIZE(drbd_tla_nl_policy)-1,
};

/*
 * Magic: define multicast groups
 * Magic: define multicast group registration helper
 */
#undef GENL_mc_group
#define GENL_mc_group(group)						\
static struct genl_multicast_group					\
CONCAT_(GENL_MAGIC_FAMILY, _mcg_ ## group) __read_mostly = {		\
	.name = #group,							\
};									\
static int CONCAT_(GENL_MAGIC_FAMILY, _genl_multicast_ ## group)(	\
	struct sk_buff *skb, gfp_t flags)				\
{									\
	unsigned int group_id =						\
		CONCAT_(GENL_MAGIC_FAMILY, _mcg_ ## group).id;	\
	if (!group_id)							\
		return -EINVAL;						\
	return genlmsg_multicast(skb, 0, group_id, flags);		\
}

#include GENL_MAGIC_INCLUDE_FILE

int CONCAT_(GENL_MAGIC_FAMILY, _genl_register)(void)
{
	int err = genl_register_family_with_ops(&ZZZ_genl_family,
		ZZZ_genl_ops, ARRAY_SIZE(ZZZ_genl_ops));
	if (err)
		return err;
#undef GENL_mc_group
#define GENL_mc_group(group)						\
	err = genl_register_mc_group(&ZZZ_genl_family,			\
		&CONCAT_(GENL_MAGIC_FAMILY, _mcg_ ## group));		\
	if (err)							\
		goto fail;						\
	else								\
		pr_info("%s: mcg %s: %u\n", #group,			\
			__stringify(GENL_MAGIC_FAMILY),			\
			CONCAT_(GENL_MAGIC_FAMILY, _mcg_ ## group).id);

#include GENL_MAGIC_INCLUDE_FILE

#undef GENL_mc_group
#define GENL_mc_group(group)
	return 0;
fail:
	genl_unregister_family(&ZZZ_genl_family);
	return err;
}

void CONCAT_(GENL_MAGIC_FAMILY, _genl_unregister)(void)
{
	genl_unregister_family(&ZZZ_genl_family);
}

/*
 * Magic: provide conversion functions					{{{1
 * populate skb from struct.
 *									{{{2
 */

#undef GENL_op
#define GENL_op(op_name, op_num, handler, tla_list)

#undef GENL_struct
#define GENL_struct(tag_name, tag_number, s_name, s_fields)		\
static int s_name ## _to_skb(struct sk_buff *skb, struct s_name *s,	\
		const bool exclude_sensitive)				\
{									\
	struct nlattr *tla = nla_nest_start(skb, tag_number);		\
	if (!tla)							\
		goto nla_put_failure;					\
	DPRINT_TLA(#s_name, "-=>", #tag_name);				\
	s_fields							\
	nla_nest_end(skb, tla);						\
	return 0;							\
									\
nla_put_failure:							\
	if (tla)							\
		nla_nest_cancel(skb, tla);				\
        return -EMSGSIZE;						\
}									\
static inline int s_name ## _to_priv_skb(struct sk_buff *skb,		\
		struct s_name *s)					\
{									\
	return s_name ## _to_skb(skb, s, 0);				\
}									\
static inline int s_name ## _to_unpriv_skb(struct sk_buff *skb,		\
		struct s_name *s)					\
{									\
	return s_name ## _to_skb(skb, s, 1);				\
}


#undef __field
#define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put)	\
	if (!exclude_sensitive || !((attr_flag) & GENLA_F_SENSITIVE)) {	\
		DPRINT_FIELD(">>", nla_type, name, s, NULL);		\
		__put(skb, attr_nr, s->name);				\
	}

#undef __array
#define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \
	if (!exclude_sensitive || !((attr_flag) & GENLA_F_SENSITIVE)) {	\
		DPRINT_ARRAY(">>",nla_type, name, s, NULL);		\
		__put(skb, attr_nr, min_t(int, maxlen,			\
			s->name ## _len + (nla_type == NLA_NUL_STRING)),\
						s->name);		\
	}

#include GENL_MAGIC_INCLUDE_FILE


/* Functions for initializing structs to default values.  */

#undef __field
#define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put)
#undef __array
#define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put)
#undef __u32_field_def
#define __u32_field_def(attr_nr, attr_flag, name, default)		\
	x->name = default;
#undef __flg_field_def
#define __flg_field_def(attr_nr, attr_flag, name, default)		\
	x->name = default;
#undef __str_field_def
#define __str_field_def(attr_nr, attr_flag, name, maxlen)		\
	memset(x->name, 0, sizeof(x->name));				\
	x->name ## _len = 0;
#undef GENL_struct
#define GENL_struct(tag_name, tag_number, s_name, s_fields)		\
static void set_ ## s_name ## _defaults(struct s_name *x) __attribute__((unused)); \
static void set_ ## s_name ## _defaults(struct s_name *x) {	\
s_fields								\
}

#include GENL_MAGIC_INCLUDE_FILE

#endif /* __KERNEL__ */

/* }}}1 */
#endif /* GENL_MAGIC_FUNC_H */
/* vim: set foldmethod=marker foldlevel=1 nofoldenable : */
Commit	Line	Data
ec2c35ac LE	1	#ifndef GENL_MAGIC_FUNC_H
	2	#define GENL_MAGIC_FUNC_H
	3
	4	#include <linux/genl_magic_struct.h>
	5
	6	/*
	7	* Extension of genl attribute validation policies {{{1
	8	* {{{2
	9	*/
	10
	11	/**
	12	* nla_is_required - return true if this attribute is required
	13	* @nla: netlink attribute
	14	*/
	15	static inline int nla_is_required(const struct nlattr *nla)
	16	{
	17	return nla->nla_type & GENLA_F_REQUIRED;
	18	}
	19
	20	/**
	21	* nla_is_mandatory - return true if understanding this attribute is mandatory
	22	* @nla: netlink attribute
	23	* Note: REQUIRED attributes are implicitly MANDATORY as well
	24	*/
	25	static inline int nla_is_mandatory(const struct nlattr *nla)
	26	{
	27	return nla->nla_type & (GENLA_F_MANDATORY \| GENLA_F_REQUIRED);
	28	}
	29
	30	/* Functionality to be integrated into nla_parse(), and validate_nla(),
	31	* respectively.
	32	*
	33	* Enforcing the "mandatory" bit is done here,
	34	* by rejecting unknown mandatory attributes.
	35	*
	36	* Part of enforcing the "required" flag would mean to embed it into
	37	* nla_policy.type, and extending validate_nla(), which currently does
	38	* BUG_ON(pt->type > NLA_TYPE_MAX); we have to work on existing kernels,
	39	* so we cannot do that. Thats why enforcing "required" is done in the
	40	* generated assignment functions below. */
	41	static int nla_check_unknown(int maxtype, struct nlattr *head, int len)
	42	{
	43	struct nlattr *nla;
	44	int rem;
	45	nla_for_each_attr(nla, head, len, rem) {
	46	__u16 type = nla_type(nla);
	47	if (type > maxtype && nla_is_mandatory(nla))
	48	return -EOPNOTSUPP;
	49	}
	50	return 0;
	51	}
	52
	53	/*
	54	* Magic: declare tla policy {{{1
	55	* Magic: declare nested policies
	56	* {{{2
	57	*/
	58	#undef GENL_mc_group
	59	#define GENL_mc_group(group)
	60
	61	#undef GENL_notification
	62	#define GENL_notification(op_name, op_num, mcast_group, tla_list)
	63
	64	#undef GENL_op
65	#define GENL_op(op_name, op_num, handler, tla_list)
66
67	#undef GENL_struct
68	#define GENL_struct(tag_name, tag_number, s_name, s_fields) \
69	[tag_name] = { .type = NLA_NESTED },
70
71	static struct nla_policy CONCAT_(GENL_MAGIC_FAMILY, _tla_nl_policy)[] = {
72	#include GENL_MAGIC_INCLUDE_FILE
73	};
74
75	#undef GENL_struct
76	#define GENL_struct(tag_name, tag_number, s_name, s_fields) \
77	static struct nla_policy s_name ## _nl_policy[] __read_mostly = \
78	{ s_fields };
79
80	#undef __field
81	#define __field(attr_nr, attr_flag, name, nla_type, _type, __get, __put) \
82	[__nla_type(attr_nr)] = { .type = nla_type },
83
84	#undef __array
85	#define __array(attr_nr, attr_flag, name, nla_type, _type, maxlen, \
86	__get, __put) \
87	[__nla_type(attr_nr)] = { .type = nla_type, \
88	.len = maxlen - (nla_type == NLA_NUL_STRING) },
89
90	#include GENL_MAGIC_INCLUDE_FILE
91
92	#ifndef __KERNEL__
93	#ifndef pr_info
94	#define pr_info(args...) fprintf(stderr, args);
95	#endif
96	#endif
97
3b98c0c2	98	#ifdef GENL_MAGIC_DEBUG
ec2c35ac LE	99	static void dprint_field(const char *dir, int nla_type,
	100	const char name, void valp)
	101	{
	102	__u64 val = valp ? (__u32 )valp : 1;
	103	switch (nla_type) {
	104	case NLA_U8: val = (__u8)val;
	105	case NLA_U16: val = (__u16)val;
	106	case NLA_U32: val = (__u32)val;
	107	pr_info("%s attr %s: %d 0x%08x\n", dir,
	108	name, (int)val, (unsigned)val);
	109	break;
	110	case NLA_U64:
	111	val = (__u64)valp;
	112	pr_info("%s attr %s: %lld 0x%08llx\n", dir,
	113	name, (long long)val, (unsigned long long)val);
	114	break;
	115	case NLA_FLAG:
	116	if (val)
	117	pr_info("%s attr %s: set\n", dir, name);
	118	break;
	119	}
	120	}
	121
	122	static void dprint_array(const char *dir, int nla_type,
	123	const char name, const char val, unsigned len)
	124	{
	125	switch (nla_type) {
	126	case NLA_NUL_STRING:
	127	if (len && val[len-1] == '\0')
	128	len--;
	129	pr_info("%s attr %s: [len:%u] '%s'\n", dir, name, len, val);
	130	break;
	131	default:
	132	/* we can always show 4 byte,
	133	* thats what nlattr are aligned to. */
	134	pr_info("%s attr %s: [len:%u] %02x%02x%02x%02x ...\n",
	135	dir, name, len, val[0], val[1], val[2], val[3]);
	136	}
	137	}
	138
	139	#define DPRINT_TLA(a, op, b) pr_info("%s %s %s\n", a, op, b);
	140
	141	/* Name is a member field name of the struct s.
	142	* If s is NULL (only parsing, no copy requested in *_from_attrs()),
	143	* nla is supposed to point to the attribute containing the information
	144	* corresponding to that struct member. */
	145	#define DPRINT_FIELD(dir, nla_type, name, s, nla) \
	146	do { \
	147	if (s) \
	148	dprint_field(dir, nla_type, #name, &s->name); \
	149	else if (nla) \
	150	dprint_field(dir, nla_type, #name, \
	151	(nla_type == NLA_FLAG) ? NULL \
	152	: nla_data(nla)); \
	153	} while (0)
	154
	155	#define DPRINT_ARRAY(dir, nla_type, name, s, nla) \
	156	do { \
	157	if (s) \
	158	dprint_array(dir, nla_type, #name, \
	159	s->name, s->name ## _len); \
	160	else if (nla) \
	161	dprint_array(dir, nla_type, #name, \
	162	nla_data(nla), nla_len(nla)); \
163	} while (0)
164	#else
165	#define DPRINT_TLA(a, op, b) do {} while (0)
166	#define DPRINT_FIELD(dir, nla_type, name, s, nla) do {} while (0)
167	#define DPRINT_ARRAY(dir, nla_type, name, s, nla) do {} while (0)
168	#endif
169
170	/*
171	* Magic: provide conversion functions {{{1
172	* populate struct from attribute table:
173	* {{{2
174	*/
175
176	/* processing of generic netlink messages is serialized.
177	* use one static buffer for parsing of nested attributes */
178	static struct nlattr *nested_attr_tb[128];
179
180	#ifndef BUILD_BUG_ON
181	/* Force a compilation error if condition is true */
182	#define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
183	/* Force a compilation error if condition is true, but also produce a
184	result (of value 0 and type size_t), so the expression can be used
185	e.g. in a structure initializer (or where-ever else comma expressions
186	aren't permitted). */
187	#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
188	#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
189	#endif
190
191	#undef GENL_struct
192	#define GENL_struct(tag_name, tag_number, s_name, s_fields) \
f399002e LE	193	/* _from_attrs functions are static, but potentially unused / \
	194	static int __ ## s_name ## _from_attrs(struct s_name *s, \
	195	struct genl_info *info, bool exclude_invariants) \
ec2c35ac LE	196	{ \
ec2c35ac LE	197	const int maxtype = ARRAY_SIZE(s_name ## _nl_policy)-1; \
f399002e	198	struct nlattr *tla = info->attrs[tag_number]; \
ec2c35ac LE	199	struct nlattr **ntb = nested_attr_tb; \
	200	struct nlattr *nla; \
	201	int err; \
	202	BUILD_BUG_ON(ARRAY_SIZE(s_name ## _nl_policy) > ARRAY_SIZE(nested_attr_tb)); \
	203	if (!tla) \
	204	return -ENOMSG; \
	205	DPRINT_TLA(#s_name, "<=-", #tag_name); \
	206	err = nla_parse_nested(ntb, maxtype, tla, s_name ## _nl_policy); \
	207	if (err) \
	208	return err; \
	209	err = nla_check_unknown(maxtype, nla_data(tla), nla_len(tla)); \
	210	if (err) \
	211	return err; \
	212	\
	213	s_fields \
	214	return 0; \
f399002e LE	215	} __attribute__((unused)) \
	216	static int s_name ## _from_attrs(struct s_name *s, \
	217	struct genl_info *info) \
	218	{ \
	219	return __ ## s_name ## _from_attrs(s, info, false); \
	220	} __attribute__((unused)) \
	221	static int s_name ## _from_attrs_for_change(struct s_name *s, \
	222	struct genl_info *info) \
	223	{ \
	224	return __ ## s_name ## _from_attrs(s, info, true); \
	225	} __attribute__((unused)) \
ec2c35ac	226
f399002e	227	#define __assign(attr_nr, attr_flag, name, nla_type, type, assignment...) \
ec2c35ac LE	228	nla = ntb[__nla_type(attr_nr)]; \
ec2c35ac LE	229	if (nla) { \
f399002e LE	230	if (exclude_invariants && ((attr_flag) & GENLA_F_INVARIANT)) { \
	231	pr_info("<< must not change invariant attr: %s\n", #name); \
	232	return -EEXIST; \
	233	} \
	234	assignment; \
	235	} else if (exclude_invariants && ((attr_flag) & GENLA_F_INVARIANT)) { \
	236	/* attribute missing from payload, */ \
	237	/* which was expected */ \
ec2c35ac LE	238	} else if ((attr_flag) & GENLA_F_REQUIRED) { \
	239	pr_info("<< missing attr: %s\n", #name); \
	240	return -ENOMSG; \
	241	}
	242
f399002e LE	243	#undef __field
	244	#define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \
	245	__assign(attr_nr, attr_flag, name, nla_type, type, \
	246	if (s) \
	247	s->name = __get(nla); \
	248	DPRINT_FIELD("<<", nla_type, name, s, nla))
	249
ec2c35ac LE	250	/* validate_nla() already checked nla_len <= maxlen appropriately. */
	251	#undef __array
	252	#define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \
f399002e	253	__assign(attr_nr, attr_flag, name, nla_type, type, \
ec2c35ac LE	254	if (s) \
	255	s->name ## _len = \
	256	__get(s->name, nla, maxlen); \
f399002e	257	DPRINT_ARRAY("<<", nla_type, name, s, nla))
ec2c35ac LE	258
	259	#include GENL_MAGIC_INCLUDE_FILE
	260
	261	#undef GENL_struct
	262	#define GENL_struct(tag_name, tag_number, s_name, s_fields)
	263
	264	/*
	265	* Magic: define op number to op name mapping {{{1
	266	* {{{2
	267	*/
	268	const char *CONCAT_(GENL_MAGIC_FAMILY, _genl_cmd_to_str)(__u8 cmd)
	269	{
	270	switch (cmd) {
	271	#undef GENL_op
	272	#define GENL_op(op_name, op_num, handler, tla_list) \
	273	case op_num: return #op_name;
	274	#include GENL_MAGIC_INCLUDE_FILE
	275	default:
	276	return "unknown";
	277	}
	278	}
	279
	280	#ifdef __KERNEL__
	281	#include <linux/stringify.h>
	282	/*
	283	* Magic: define genl_ops {{{1
	284	* {{{2
	285	*/
	286
	287	#undef GENL_op
	288	#define GENL_op(op_name, op_num, handler, tla_list) \
	289	{ \
	290	handler \
	291	.cmd = op_name, \
	292	.policy = CONCAT_(GENL_MAGIC_FAMILY, _tla_nl_policy), \
	293	},
	294
	295	#define ZZZ_genl_ops CONCAT_(GENL_MAGIC_FAMILY, _genl_ops)
	296	static struct genl_ops ZZZ_genl_ops[] __read_mostly = {
	297	#include GENL_MAGIC_INCLUDE_FILE
	298	};
	299
	300	#undef GENL_op
	301	#define GENL_op(op_name, op_num, handler, tla_list)
	302
	303	/*
	304	* Define the genl_family, multicast groups, {{{1
	305	* and provide register/unregister functions.
	306	* {{{2
	307	*/
	308	#define ZZZ_genl_family CONCAT_(GENL_MAGIC_FAMILY, _genl_family)
	309	static struct genl_family ZZZ_genl_family __read_mostly = {
	310	.id = GENL_ID_GENERATE,
	311	.name = __stringify(GENL_MAGIC_FAMILY),
	312	.version = GENL_MAGIC_VERSION,
	313	#ifdef GENL_MAGIC_FAMILY_HDRSZ
	314	.hdrsize = NLA_ALIGN(GENL_MAGIC_FAMILY_HDRSZ),
	315	#endif
	316	.maxattr = ARRAY_SIZE(drbd_tla_nl_policy)-1,
	317	};
	318
	319	/*
	320	* Magic: define multicast groups
	321	* Magic: define multicast group registration helper
322	*/
323	#undef GENL_mc_group
324	#define GENL_mc_group(group) \
325	static struct genl_multicast_group \
326	CONCAT_(GENL_MAGIC_FAMILY, _mcg_ ## group) __read_mostly = { \
327	.name = #group, \
328	}; \
329	static int CONCAT_(GENL_MAGIC_FAMILY, _genl_multicast_ ## group)( \
330	struct sk_buff *skb, gfp_t flags) \
331	{ \
332	unsigned int group_id = \
333	CONCAT_(GENL_MAGIC_FAMILY, _mcg_ ## group).id; \
334	if (!group_id) \
335	return -EINVAL; \
336	return genlmsg_multicast(skb, 0, group_id, flags); \
337	}
338
339	#include GENL_MAGIC_INCLUDE_FILE
340
341	int CONCAT_(GENL_MAGIC_FAMILY, _genl_register)(void)
342	{
343	int err = genl_register_family_with_ops(&ZZZ_genl_family,
344	ZZZ_genl_ops, ARRAY_SIZE(ZZZ_genl_ops));
345	if (err)
346	return err;
347	#undef GENL_mc_group
348	#define GENL_mc_group(group) \
349	err = genl_register_mc_group(&ZZZ_genl_family, \
350	&CONCAT_(GENL_MAGIC_FAMILY, _mcg_ ## group)); \
351	if (err) \
352	goto fail; \
353	else \
354	pr_info("%s: mcg %s: %u\n", #group, \
355	__stringify(GENL_MAGIC_FAMILY), \
356	CONCAT_(GENL_MAGIC_FAMILY, _mcg_ ## group).id);
357
358	#include GENL_MAGIC_INCLUDE_FILE
359
360	#undef GENL_mc_group
361	#define GENL_mc_group(group)
362	return 0;
363	fail:
364	genl_unregister_family(&ZZZ_genl_family);
365	return err;
366	}
367
368	void CONCAT_(GENL_MAGIC_FAMILY, _genl_unregister)(void)
369	{
370	genl_unregister_family(&ZZZ_genl_family);
371	}
372
373	/*
374	* Magic: provide conversion functions {{{1
375	* populate skb from struct.
376	* {{{2
377	*/
378
379	#undef GENL_op
380	#define GENL_op(op_name, op_num, handler, tla_list)
381
382	#undef GENL_struct
383	#define GENL_struct(tag_name, tag_number, s_name, s_fields) \
384	static int s_name ## _to_skb(struct sk_buff skb, struct s_name s, \
385	const bool exclude_sensitive) \
386	{ \
387	struct nlattr *tla = nla_nest_start(skb, tag_number); \
388	if (!tla) \
389	goto nla_put_failure; \
390	DPRINT_TLA(#s_name, "-=>", #tag_name); \
391	s_fields \
392	nla_nest_end(skb, tla); \
393	return 0; \
394	\
395	nla_put_failure: \
396	if (tla) \
397	nla_nest_cancel(skb, tla); \
398	return -EMSGSIZE; \
399	} \
400	static inline int s_name ## _to_priv_skb(struct sk_buff *skb, \
401	struct s_name *s) \
402	{ \
403	return s_name ## _to_skb(skb, s, 0); \
404	} \
405	static inline int s_name ## _to_unpriv_skb(struct sk_buff *skb, \
406	struct s_name *s) \
407	{ \
408	return s_name ## _to_skb(skb, s, 1); \
409	}
410
411
412	#undef __field
413	#define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put) \
414	if (!exclude_sensitive \|\| !((attr_flag) & GENLA_F_SENSITIVE)) { \
415	DPRINT_FIELD(">>", nla_type, name, s, NULL); \
416	__put(skb, attr_nr, s->name); \
417	}
418
419	#undef __array
420	#define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put) \
421	if (!exclude_sensitive \|\| !((attr_flag) & GENLA_F_SENSITIVE)) { \
422	DPRINT_ARRAY(">>",nla_type, name, s, NULL); \
423	__put(skb, attr_nr, min_t(int, maxlen, \
424	s->name ## _len + (nla_type == NLA_NUL_STRING)),\
425	s->name); \
426	}
427
428	#include GENL_MAGIC_INCLUDE_FILE
429
b966b5dd AG	430
	431	/* Functions for initializing structs to default values. */
	432
	433	#undef __field
	434	#define __field(attr_nr, attr_flag, name, nla_type, type, __get, __put)
	435	#undef __array
	436	#define __array(attr_nr, attr_flag, name, nla_type, type, maxlen, __get, __put)
	437	#undef __u32_field_def
	438	#define __u32_field_def(attr_nr, attr_flag, name, default) \
	439	x->name = default;
	440	#undef __flg_field_def
	441	#define __flg_field_def(attr_nr, attr_flag, name, default) \
	442	x->name = default;
	443	#undef __str_field_def
	444	#define __str_field_def(attr_nr, attr_flag, name, maxlen) \
	445	memset(x->name, 0, sizeof(x->name)); \
	446	x->name ## _len = 0;
	447	#undef GENL_struct
	448	#define GENL_struct(tag_name, tag_number, s_name, s_fields) \
	449	static void set_ ## s_name ## _defaults(struct s_name *x) __attribute__((unused)); \
	450	static void set_ ## s_name ## _defaults(struct s_name *x) { \
	451	s_fields \
	452	}
	453
	454	#include GENL_MAGIC_INCLUDE_FILE
	455
ec2c35ac LE	456	#endif /* __KERNEL__ */
	457
	458	/* }}}1 */
	459	#endif /* GENL_MAGIC_FUNC_H */
	460	/* vim: set foldmethod=marker foldlevel=1 nofoldenable : */