rlm_interval.c File Reference

Interval limiting module providing an xlat function. More...

#include <freeradius-devel/server/base.h>
#include <freeradius-devel/server/main_loop.h>
#include <freeradius-devel/server/module_rlm.h>
#include <freeradius-devel/unlang/xlat_func.h>
#include <freeradius-devel/util/rb.h>
#include <freeradius-devel/util/slab.h>
#include <freeradius-devel/util/timer.h>
#include <freeradius-devel/util/debug.h>
#include <freeradius-devel/util/strerror.h>
#include <pthread.h>

Include dependency graph for rlm_interval.c:

Go to the source code of this file.

Data Structures
struct	rlm_interval_entry_t
	RBTree entry for keyed lookups. More...
struct	rlm_interval_mutable_t
	Mutable data for global scope (allocated outside mprotected instance data) More...
struct	rlm_interval_t
	Module instance data. More...
struct	rlm_interval_thread_t
	Module thread instance data. More...
struct	rlm_interval_xlat_inst_t
	Xlat instance data - stores the xlat expression pointer for keyless lookups. More...
struct	rlm_interval_xlat_thread_inst_t
	Xlat thread instance data - stores last_used for keyless thread-scope lookups. More...

Enumerations
enum	rlm_interval_scope_t {   INTERVAL_SCOPE_GLOBAL = 0 ,   INTERVAL_SCOPE_THREAD }

Functions
static int	interval_check (fr_rb_tree_t *tree, rlm_interval_thread_t *thread, void *owner, fr_timer_cb_t expire, rlm_interval_entry_t *find, fr_time_delta_t interval)
	Check interval limit.
static int8_t	interval_entry_cmp (void const *one, void const *two)
static void	interval_expire_global (UNUSED fr_timer_list_t *tl, UNUSED fr_time_t now, void *uctx)
	Timer callback to expire entries (global scope)
static void	interval_expire_thread (UNUSED fr_timer_list_t *tl, UNUSED fr_time_t now, void *uctx)
	Timer callback to expire entries (thread scope)
static xlat_action_t	interval_xlat_global (TALLOC_CTX *ctx, fr_dcursor_t *out, xlat_ctx_t const *xctx, request_t *request, fr_value_box_list_t *in)
	Global scope xlat - always uses mutex-protected tree.
static int	interval_xlat_instantiate (xlat_inst_ctx_t const *xctx)
static xlat_action_t	interval_xlat_thread (TALLOC_CTX *ctx, fr_dcursor_t *out, xlat_ctx_t const *xctx, request_t *request, fr_value_box_list_t *in)
	Thread scope xlat - uses thread-local tree or module thread instance.
static int	interval_xlat_thread_instantiate (xlat_thread_inst_ctx_t const *xctx)
static int	mod_bootstrap (module_inst_ctx_t const *mctx)
static int	mod_detach (module_detach_ctx_t const *mctx)
static int	mod_instantiate (module_inst_ctx_t const *mctx)
static int	mod_thread_instantiate (module_thread_inst_ctx_t const *mctx)

Variables
static fr_table_num_sorted_t const	interval_scope_table []
static size_t	interval_scope_table_len = NUM_ELEMENTS(interval_scope_table)
static xlat_arg_parser_t const	interval_xlat_args []
static const conf_parser_t	module_config []
static conf_parser_t	reuse_config []
module_rlm_t	rlm_interval

Detailed Description

Interval limiting module providing an xlat function.

Id

1a042ab5071847a64ce19818a0748b60dcb2dfad

Copyright

2026 The FreeRADIUS server project

2026 Arran Cudbard-Bell a.cud.nosp@m.bard.nosp@m.b@fre.nosp@m.erad.nosp@m.ius.o.nosp@m.rg

Definition in file rlm_interval.c.

---

Data Structure Documentation

rlm_interval_entry_t

struct rlm_interval_entry_t

RBTree entry for keyed lookups.

Definition at line 53 of file rlm_interval.c.

Collaboration diagram for rlm_interval_entry_t:

Data Fields
fr_timer_t *	ev	Expiry timer.
fr_value_box_t	key	Key stored in value box.
fr_rb_node_t	node	RBTree node.
void *	owner	Back-pointer to mutable_t or thread_t.

rlm_interval_mutable_t

struct rlm_interval_mutable_t

Mutable data for global scope (allocated outside mprotected instance data)

Definition at line 65 of file rlm_interval.c.

Collaboration diagram for rlm_interval_mutable_t:

Data Fields
pthread_mutex_t	mutex	Mutex for thread safety.
fr_rb_tree_t *	tree	RBTree for keyed lookups.

rlm_interval_t

struct rlm_interval_t

Module instance data.

Definition at line 72 of file rlm_interval.c.

Collaboration diagram for rlm_interval_t:

Data Fields
rlm_interval_mutable_t *	mutable	Mutable data for global scope.
fr_slab_config_t	reuse	Slab allocator configuration.
rlm_interval_scope_t	scope	Global or thread-local scope.

rlm_interval_thread_t

struct rlm_interval_thread_t

Module thread instance data.

Definition at line 80 of file rlm_interval.c.

Collaboration diagram for rlm_interval_thread_t:

Data Fields
interval_slab_list_t *	slab	Slab allocator for entries.
fr_timer_list_t *	tl	Timer list for entry expiry.
fr_rb_tree_t *	tree	RBTree for keyed lookups (thread scope only).

rlm_interval_xlat_inst_t

struct rlm_interval_xlat_inst_t

Xlat instance data - stores the xlat expression pointer for keyless lookups.

Definition at line 88 of file rlm_interval.c.

Collaboration diagram for rlm_interval_xlat_inst_t:

Data Fields
xlat_exp_t const *	ex	Cached for keyless lookups.

rlm_interval_xlat_thread_inst_t

struct rlm_interval_xlat_thread_inst_t

Xlat thread instance data - stores last_used for keyless thread-scope lookups.

Definition at line 94 of file rlm_interval.c.

Collaboration diagram for rlm_interval_xlat_thread_inst_t:

Data Fields
fr_time_t	last_used	Last used time for this call site.

Enumeration Type Documentation

rlm_interval_scope_t

enum rlm_interval_scope_t

Enumerator
INTERVAL_SCOPE_GLOBAL
INTERVAL_SCOPE_THREAD

Definition at line 40 of file rlm_interval.c.

Function Documentation

interval_check()

static int interval_check ( fr_rb_tree_t *  tree, rlm_interval_thread_t *  thread, void *  owner, fr_timer_cb_t  expire, rlm_interval_entry_t *  find, fr_time_delta_t  interval  )

static

Check interval limit.

Note

Don't be tempted to move mutex handling in here. Yes you could probably reduce the size of the critical region, but you're going to break something and miss interaction effects. Just don't do it.

Parameters

[in]	tree	RBTree for lookups.
[in]	thread	Thread instance (for timer list and slab).
[in]	owner	Back-pointer to store in new entries (for expiry callback).
[in]	expire	Expiry callback function.
[in]	find	Entry with key to search for.
[in]	interval	Interval limit interval.

Returns

• 1 if allowed.
• 0 if interval limited.
• -1 on error.

Definition at line 172 of file rlm_interval.c.

Here is the call graph for this function:

Here is the caller graph for this function:

interval_entry_cmp()

static int8_t interval_entry_cmp ( void const *  one, void const *  two  )

static

Definition at line 118 of file rlm_interval.c.

Here is the call graph for this function:

Here is the caller graph for this function:

interval_expire_global()

static void interval_expire_global ( UNUSED fr_timer_list_t *  tl, UNUSED fr_time_t  now, void *  uctx  )

static

Timer callback to expire entries (global scope)

Definition at line 143 of file rlm_interval.c.

Here is the call graph for this function:

Here is the caller graph for this function:

interval_expire_thread()

static void interval_expire_thread ( UNUSED fr_timer_list_t *  tl, UNUSED fr_time_t  now, void *  uctx  )

static

Timer callback to expire entries (thread scope)

Definition at line 132 of file rlm_interval.c.

Here is the call graph for this function:

Here is the caller graph for this function:

interval_xlat_global()

static xlat_action_t interval_xlat_global ( TALLOC_CTX *  ctx, fr_dcursor_t *  out, xlat_ctx_t const *  xctx, request_t *  request, fr_value_box_list_t *  in  )

static

Global scope xlat - always uses mutex-protected tree.

Definition at line 218 of file rlm_interval.c.

Here is the call graph for this function:

Here is the caller graph for this function:

interval_xlat_instantiate()

static int interval_xlat_instantiate ( xlat_inst_ctx_t const *  xctx )

static

Definition at line 329 of file rlm_interval.c.

Here is the caller graph for this function:

interval_xlat_thread()

static xlat_action_t interval_xlat_thread ( TALLOC_CTX *  ctx, fr_dcursor_t *  out, xlat_ctx_t const *  xctx, request_t *  request, fr_value_box_list_t *  in  )

static

Thread scope xlat - uses thread-local tree or module thread instance.

Definition at line 270 of file rlm_interval.c.

Here is the call graph for this function:

Here is the caller graph for this function:

interval_xlat_thread_instantiate()

static int interval_xlat_thread_instantiate ( xlat_thread_inst_ctx_t const *  xctx )

static

Definition at line 337 of file rlm_interval.c.

Here is the caller graph for this function:

mod_bootstrap()

static int mod_bootstrap ( module_inst_ctx_t const *  mctx )

static

Definition at line 420 of file rlm_interval.c.

Here is the call graph for this function:

mod_detach()

static int mod_detach ( module_detach_ctx_t const *  mctx )

static

Definition at line 387 of file rlm_interval.c.

Here is the call graph for this function:

mod_instantiate()

static int mod_instantiate ( module_inst_ctx_t const *  mctx )

static

Definition at line 399 of file rlm_interval.c.

Here is the call graph for this function:

mod_thread_instantiate()

static int mod_thread_instantiate ( module_thread_inst_ctx_t const *  mctx )

static

Definition at line 349 of file rlm_interval.c.

Here is the call graph for this function:

Variable Documentation

interval_scope_table

fr_table_num_sorted_t const interval_scope_table[]

static

Initial value:

= {
        { L("global"),  INTERVAL_SCOPE_GLOBAL },
        { L("thread"),  INTERVAL_SCOPE_THREAD }
}

Definition at line 45 of file rlm_interval.c.

interval_scope_table_len

size_t interval_scope_table_len = NUM_ELEMENTS(interval_scope_table)

static

Definition at line 49 of file rlm_interval.c.

interval_xlat_args

xlat_arg_parser_t const interval_xlat_args[]

static

Initial value:

= {
        { .required = true, .single = true, .type = FR_TYPE_TIME_DELTA },
        { .single = true, .type = FR_TYPE_STRING },
        XLAT_ARG_PARSER_TERMINATOR
}

Definition at line 112 of file rlm_interval.c.

module_config

const conf_parser_t module_config[]

static

Initial value:

= {
        { FR_CONF_OFFSET("scope", rlm_interval_t, scope),
          .func = cf_table_parse_int,
          .uctx = &(cf_table_parse_ctx_t){ .table = interval_scope_table, .len = &interval_scope_table_len },
          .dflt = "global" },
        { FR_CONF_OFFSET_SUBSECTION("reuse", 0, rlm_interval_t, reuse, reuse_config) },
        CONF_PARSER_TERMINATOR
}

Definition at line 103 of file rlm_interval.c.

reuse_config

conf_parser_t reuse_config[]

static

Initial value:

= {
        FR_SLAB_CONFIG_CONF_PARSER
        CONF_PARSER_TERMINATOR
}

Definition at line 98 of file rlm_interval.c.

rlm_interval

module_rlm_t rlm_interval

Initial value:

= {
        .common = {
                .magic                  = MODULE_MAGIC_INIT,
                .name                   = "interval",
                .inst_size              = sizeof(rlm_interval_t),
                .thread_inst_size       = sizeof(rlm_interval_thread_t),
                .config                 = module_config,
                .bootstrap              = mod_bootstrap,
                .instantiate            = mod_instantiate,
                .detach                 = mod_detach,
                .thread_instantiate     = mod_thread_instantiate,
        }
}

Definition at line 455 of file rlm_interval.c.