Data Structures | Macros | Typedefs | Functions
mesh.h File Reference

This file contains functions to assist in dealing with a mesh of query states. More...

#include "util/rbtree.h"
#include "util/netevent.h"
#include "util/data/msgparse.h"
#include "util/module.h"
#include "services/modstack.h"

Data Structures

struct  mesh_area
 Mesh of query states. More...
 
struct  mesh_state
 A mesh query state Unique per qname, qtype, qclass (from the qstate). More...
 
struct  mesh_state_ref
 Rbtree reference to a mesh_state. More...
 
struct  mesh_reply
 Reply to a client. More...
 
struct  mesh_cb
 Callback to result routine. More...
 

Macros

#define MESH_MAX_ACTIVATION   3000
 Maximum number of mesh state activations. More...
 
#define MESH_MAX_SUBSUB   1024
 Max number of references-to-references-to-references. More...
 

Typedefs

typedef void(* mesh_cb_func_t )(void *, int, struct sldns_buffer *, enum sec_status, char *)
 Mesh result callback func. More...
 

Functions

struct mesh_areamesh_create (struct module_stack *stack, struct module_env *env)
 Allocate mesh, to empty. More...
 
void mesh_delete (struct mesh_area *mesh)
 Delete mesh, and all query states and replies in it. More...
 
void mesh_new_client (struct mesh_area *mesh, struct query_info *qinfo, uint16_t qflags, struct edns_data *edns, struct comm_reply *rep, uint16_t qid)
 New query incoming from clients. More...
 
int mesh_new_callback (struct mesh_area *mesh, struct query_info *qinfo, uint16_t qflags, struct edns_data *edns, struct sldns_buffer *buf, uint16_t qid, mesh_cb_func_t cb, void *cb_arg)
 New query with callback. More...
 
void mesh_new_prefetch (struct mesh_area *mesh, struct query_info *qinfo, uint16_t qflags, time_t leeway)
 New prefetch message. More...
 
void mesh_report_reply (struct mesh_area *mesh, struct outbound_entry *e, struct comm_reply *reply, int what)
 Handle new event from the wire. More...
 
void mesh_detach_subs (struct module_qstate *qstate)
 Detach-subqueries. More...
 
int mesh_attach_sub (struct module_qstate *qstate, struct query_info *qinfo, uint16_t qflags, int prime, int valrec, struct module_qstate **newq)
 Attach subquery. More...
 
void mesh_query_done (struct mesh_state *mstate)
 Query state is done, send messages to reply entries. More...
 
void mesh_walk_supers (struct mesh_area *mesh, struct mesh_state *mstate)
 Call inform_super for the super query states that are interested in the results from this query state. More...
 
void mesh_state_delete (struct module_qstate *qstate)
 Delete mesh state, cleanup and also rbtrees and so on. More...
 
struct mesh_statemesh_state_create (struct module_env *env, struct query_info *qinfo, uint16_t qflags, int prime, int valrec)
 Create and initialize a new mesh state and its query state Does not put the mesh state into rbtrees and so on. More...
 
void mesh_state_cleanup (struct mesh_state *mstate)
 Cleanup a mesh state and its query state. More...
 
void mesh_delete_all (struct mesh_area *mesh)
 Delete all mesh states from the mesh. More...
 
struct mesh_statemesh_area_find (struct mesh_area *mesh, struct query_info *qinfo, uint16_t qflags, int prime, int valrec)
 Find a mesh state in the mesh area. More...
 
int mesh_state_attachment (struct mesh_state *super, struct mesh_state *sub)
 Setup attachment super/sub relation between super and sub mesh state. More...
 
int mesh_state_add_reply (struct mesh_state *s, struct edns_data *edns, struct comm_reply *rep, uint16_t qid, uint16_t qflags, uint8_t *qname)
 Create new reply structure and attach it to a mesh state. More...
 
int mesh_state_add_cb (struct mesh_state *s, struct edns_data *edns, struct sldns_buffer *buf, mesh_cb_func_t cb, void *cb_arg, uint16_t qid, uint16_t qflags)
 Create new callback structure and attach it to a mesh state. More...
 
void mesh_run (struct mesh_area *mesh, struct mesh_state *mstate, enum module_ev ev, struct outbound_entry *e)
 Run the mesh. More...
 
void mesh_stats (struct mesh_area *mesh, const char *str)
 Print some stats about the mesh to the log. More...
 
void mesh_stats_clear (struct mesh_area *mesh)
 Clear the stats that the mesh keeps (number of queries serviced) More...
 
void mesh_log_list (struct mesh_area *mesh)
 Print all the states in the mesh to the log. More...
 
size_t mesh_get_mem (struct mesh_area *mesh)
 Calculate memory size in use by mesh and all queries inside it. More...
 
int mesh_detect_cycle (struct module_qstate *qstate, struct query_info *qinfo, uint16_t flags, int prime, int valrec)
 Find cycle; see if the given mesh is in the targets sub, or sub-sub, ... More...
 
int mesh_state_compare (const void *ap, const void *bp)
 compare two mesh_states
 
int mesh_state_ref_compare (const void *ap, const void *bp)
 compare two mesh references
 
int mesh_make_new_space (struct mesh_area *mesh, struct sldns_buffer *qbuf)
 Make space for another recursion state for a reply in the mesh. More...
 
void mesh_list_insert (struct mesh_state *m, struct mesh_state **fp, struct mesh_state **lp)
 Insert mesh state into a double linked list. More...
 
void mesh_list_remove (struct mesh_state *m, struct mesh_state **fp, struct mesh_state **lp)
 Remove mesh state from a double linked list. More...
 

Detailed Description

This file contains functions to assist in dealing with a mesh of query states.

This mesh is supposed to be thread-specific. It consists of query states (per qname, qtype, qclass) and connections between query states and the super and subquery states, and replies to send back to clients.

Macro Definition Documentation

#define MESH_MAX_ACTIVATION   3000

Maximum number of mesh state activations.

Any more is likely an infinite loop in the module. It is then terminated.

Referenced by mesh_continue().

#define MESH_MAX_SUBSUB   1024

Max number of references-to-references-to-references.

. search size. Any more is treated like 'too large', and the creation of a new dependency is failed (so that no loops can be created).

Referenced by find_in_subsub(), and mesh_detect_cycle_found().

Typedef Documentation

typedef void(* mesh_cb_func_t)(void *, int, struct sldns_buffer *, enum sec_status, char *)

Mesh result callback func.

called as func(cb_arg, rcode, buffer_with_reply, security, why_bogus);

Function Documentation

struct mesh_area* mesh_create ( struct module_stack stack,
struct module_env env 
)
void mesh_delete ( struct mesh_area mesh)

Delete mesh, and all query states and replies in it.

Parameters
meshthe mesh to delete.

References mesh_area::all, rbtree_t::count, mesh_area::histogram, mesh_delete_helper(), mesh_area::qbuf_bak, rbtree_t::root, sldns_buffer_free(), and timehist_delete().

Referenced by libworker_delete_env(), and worker_delete().

void mesh_new_client ( struct mesh_area mesh,
struct query_info qinfo,
uint16_t  qflags,
struct edns_data edns,
struct comm_reply rep,
uint16_t  qid 
)
int mesh_new_callback ( struct mesh_area mesh,
struct query_info qinfo,
uint16_t  qflags,
struct edns_data edns,
struct sldns_buffer buf,
uint16_t  qid,
mesh_cb_func_t  cb,
void *  cb_arg 
)

New query with callback.

Create new query state if needed, and add mesh_cb to it. Will run the mesh area queries to process if a new query state is created.

Parameters
meshthe mesh.
qinfoquery from client.
qflagsflags from client query.
ednsedns data from client query.
bufbuffer for reply contents.
qidquery id to reply with.
cbcallback function.
cb_argcallback user arg.
Returns
0 on error.

References mesh_area::all, BIT_CD, BIT_RD, mesh_state::cb_list, rbtree_t::count, mesh_area::env, log_assert, mesh_area_find(), mesh_run(), mesh_state_add_cb(), mesh_state_create(), mesh_state_delete(), module_event_new, mesh_state::node, mesh_area::num_detached_states, mesh_area::num_reply_addrs, mesh_area::num_reply_states, rbtree_insert(), mesh_state::reply_list, mesh_state::s, and mesh_state::super_set.

Referenced by handle_newq(), libworker_attach_mesh(), libworker_fg(), and probe_anchor().

void mesh_new_prefetch ( struct mesh_area mesh,
struct query_info qinfo,
uint16_t  qflags,
time_t  leeway 
)
void mesh_report_reply ( struct mesh_area mesh,
struct outbound_entry e,
struct comm_reply reply,
int  what 
)

Handle new event from the wire.

A serviced query has returned. The query state will be made runnable, and the mesh_area will process query states until processing is complete.

Parameters
meshthe query mesh.
eoutbound entry, with query state to run and reply pointer.
replythe comm point reply info.
whatNETEVENT_* error code (if not 0, what is wrong, TIMEOUT).

References module_qstate::mesh_info, mesh_run(), module_event_capsfail, module_event_noreply, module_event_reply, NETEVENT_CAPSFAIL, NETEVENT_NOERROR, outbound_entry::qstate, and module_qstate::reply.

Referenced by libworker_handle_reply(), libworker_handle_service_reply(), worker_handle_reply(), and worker_handle_service_reply().

void mesh_detach_subs ( struct module_qstate qstate)
int mesh_attach_sub ( struct module_qstate qstate,
struct query_info qinfo,
uint16_t  qflags,
int  prime,
int  valrec,
struct module_qstate **  newq 
)

Attach subquery.

Creates it if it does not exist already. Keeps sub and super references correct. Performs a cycle detection - for double check - and fails if there is one. Also fails if the sub-sub-references become too large. Updates stat items in mesh_area structure. Pass if it is priming query or not. return: o if error (malloc) happened. o need to initialise the new state (module init; it is a new state). so that the next run of the query with this module is successful. o no init needed, attachment successful.

Parameters
qstatethe state to find mesh state, and that wants to receive the results from the new subquery.
qinfowhat to query for (copied).
qflagswhat flags to use (RD / CD flag or not).
primeif it is a (stub) priming query.
valrecif it is a validation recursion query (lookup of key, DS).
newqIf the new subquery needs initialisation, it is returned, otherwise NULL is returned.
Returns
: false on error, true if success (and init may be needed).

References mesh_area::all, mesh_state::cb_list, rbtree_t::count, module_qstate::env, log_assert, log_err(), module_env::mesh, mesh_area_find(), mesh_detect_cycle_found(), module_qstate::mesh_info, mesh_state_attachment(), mesh_state_create(), mesh_state::node, mesh_area::num_detached_states, rbtree_insert(), mesh_state::reply_list, mesh_area::run, mesh_state::run_node, mesh_state::s, mesh_state::super_set, VERB_ALGO, and verbose().

Referenced by fptr_whitelist_modenv_attach_sub(), libworker_setup(), and worker_init().

void mesh_query_done ( struct mesh_state mstate)

Query state is done, send messages to reply entries.

Encode messages using reply entry values and the querystate (with original qinfo), using given reply_info. Pass errcode != 0 if an error reply is needed. If no reply entries, nothing is done. Must be called before a module can module_finished or return module_error. The module must handle the super query states itself as well.

Parameters
mstatemesh state that is done. return_rcode and return_msg are used for replies. return_rcode: if not 0 (NOERROR) an error is sent back (and return_msg is ignored). return_msg: reply to encode and send back to clients.

References mesh_state::cb_list, mesh_do_callback(), mesh_send_reply(), mesh_reply::next, mesh_cb::next, dns_msg::rep, mesh_state::replies_sent, mesh_state::reply_list, module_qstate::return_msg, module_qstate::return_rcode, and mesh_state::s.

Referenced by mesh_continue().

void mesh_walk_supers ( struct mesh_area mesh,
struct mesh_state mstate 
)

Call inform_super for the super query states that are interested in the results from this query state.

These can then be changed for error or results. Called when a module is module_finished or returns module_error. The super query states become runnable with event module_event_pass, it calls the current module for the super with the inform_super event.

Parameters
meshmesh area to add newly runnable modules to.
mstatethe state that has results, used to find mesh state.

References module_qstate::curmod, fptr_ok, fptr_whitelist_mod_inform_super(), module_func_block::inform_super, module_stack::mod, mesh_area::mods, RBTREE_FOR, rbtree_insert(), mesh_area::run, mesh_state::run_node, mesh_state::s, mesh_state_ref::s, and mesh_state::super_set.

Referenced by mesh_continue(), and mesh_make_new_space().

void mesh_state_delete ( struct module_qstate qstate)
struct mesh_state* mesh_state_create ( struct module_env env,
struct query_info qinfo,
uint16_t  qflags,
int  prime,
int  valrec 
)
void mesh_state_cleanup ( struct mesh_state mstate)
void mesh_delete_all ( struct mesh_area mesh)
struct mesh_state* mesh_area_find ( struct mesh_area mesh,
struct query_info qinfo,
uint16_t  qflags,
int  prime,
int  valrec 
)

Find a mesh state in the mesh area.

Pass relevant flags.

Parameters
meshthe mesh area to look in.
qinfowhat query
qflagsif RD / CD bit is set or not.
primeif it is a priming query.
valrecif it is a validation-recursion query.
Returns
: mesh state or NULL if not found.

References mesh_area::all, module_qstate::is_priming, module_qstate::is_valrec, rbnode_t::key, mesh_state::node, module_qstate::qinfo, module_qstate::query_flags, rbtree_search(), and mesh_state::s.

Referenced by mesh_attach_sub(), mesh_detect_cycle(), mesh_new_callback(), mesh_new_client(), and mesh_new_prefetch().

int mesh_state_attachment ( struct mesh_state super,
struct mesh_state sub 
)

Setup attachment super/sub relation between super and sub mesh state.

The relation must not be present when calling the function. Does not update stat items in mesh_area.

Parameters
supersuper state.
subsub state.
Returns
: 0 on alloc error.

References rbnode_t::key, log_assert, log_err(), mesh_state_ref::node, rbtree_insert(), module_qstate::region, regional_alloc(), mesh_state::s, mesh_state_ref::s, mesh_state::sub_set, and mesh_state::super_set.

Referenced by mesh_attach_sub().

int mesh_state_add_reply ( struct mesh_state s,
struct edns_data edns,
struct comm_reply rep,
uint16_t  qid,
uint16_t  qflags,
uint8_t *  qname 
)

Create new reply structure and attach it to a mesh state.

Does not update stat items in mesh area.

Parameters
sthe mesh state.
ednsedns data for reply (bufsize).
repcomm point reply info.
qidID of reply.
qflagsoriginal query flags.
qnameoriginal query name.
Returns
: 0 on alloc error.

References mesh_reply::edns, module_qstate::env, mesh_reply::next, module_env::now_tv, mesh_reply::qflags, mesh_reply::qid, module_qstate::qinfo, mesh_reply::qname, query_info::qname_len, mesh_reply::query_reply, module_qstate::region, regional_alloc(), regional_alloc_init(), mesh_state::reply_list, mesh_state::s, and mesh_reply::start_time.

Referenced by mesh_new_client().

int mesh_state_add_cb ( struct mesh_state s,
struct edns_data edns,
struct sldns_buffer buf,
mesh_cb_func_t  cb,
void *  cb_arg,
uint16_t  qid,
uint16_t  qflags 
)

Create new callback structure and attach it to a mesh state.

Does not update stat items in mesh area.

Parameters
sthe mesh state.
ednsedns data for reply (bufsize).
bufbuffer for reply
cbcallback to call with results.
cb_argcallback user arg.
qidID of reply.
qflagsoriginal query flags.
Returns
: 0 on alloc error.

References mesh_cb::buf, mesh_cb::cb, mesh_cb::cb_arg, mesh_state::cb_list, mesh_cb::edns, fptr_whitelist_mesh_cb(), log_assert, mesh_cb::next, mesh_cb::qflags, mesh_cb::qid, module_qstate::region, regional_alloc(), and mesh_state::s.

Referenced by mesh_new_callback().

void mesh_run ( struct mesh_area mesh,
struct mesh_state mstate,
enum module_ev  ev,
struct outbound_entry e 
)

Run the mesh.

Run all runnable mesh states. Which can create new runnable mesh states. Until completion. Automatically called by mesh_report_reply and mesh_new_client as needed.

Parameters
meshmesh area.
mstatefirst mesh state to run.
evevent the mstate. Others get event_pass.
eif a reply, its outbound entry.

References rbtree_t::count, module_qstate::curmod, module_qstate::env, module_qstate::ext_state, fptr_ok, fptr_whitelist_mod_operate(), rbnode_t::key, mesh_continue(), mesh_log_list(), mesh_stats(), module_stack::mod, mesh_area::mods, module_event_pass, module_func_block::name, module_func_block::operate, rbtree_delete(), regional_free_all(), module_qstate::reply, rbtree_t::root, mesh_area::run, mesh_state::s, module_env::scratch, strextstate(), VERB_ALGO, verbose(), and verbosity.

Referenced by mesh_new_callback(), mesh_new_client(), mesh_new_prefetch(), and mesh_report_reply().

void mesh_stats ( struct mesh_area mesh,
const char *  str 
)
void mesh_stats_clear ( struct mesh_area mesh)
void mesh_log_list ( struct mesh_area mesh)
size_t mesh_get_mem ( struct mesh_area mesh)

Calculate memory size in use by mesh and all queries inside it.

Parameters
meshthe mesh to examine.
Returns
size in bytes.

References mesh_area::all, mesh_area::histogram, timehist::num, mesh_area::qbuf_bak, RBTREE_FOR, module_qstate::region, regional_get_mem(), mesh_state::s, and sldns_buffer_capacity().

Referenced by worker_mem_report().

int mesh_detect_cycle ( struct module_qstate qstate,
struct query_info qinfo,
uint16_t  flags,
int  prime,
int  valrec 
)

Find cycle; see if the given mesh is in the targets sub, or sub-sub, ...

trees. If the sub-sub structure is too large, it returns 'a cycle'=2.

Parameters
qstategiven mesh querystate.
qinfoquery info for dependency.
flagsquery flags of dependency.
primeif dependency is a priming query or not.
valrecif it is a validation recursion query (lookup of key, DS).
Returns
true if the name,type,class exists and the given qstate mesh exists as a dependency of that name. Thus if qstate becomes dependent on name,type,class then a cycle is created, this is return value 1. Too large to search is value 2 (also true).

References module_qstate::env, module_env::mesh, mesh_area_find(), and mesh_detect_cycle_found().

Referenced by fptr_whitelist_modenv_detect_cycle(), libworker_setup(), and worker_init().

int mesh_make_new_space ( struct mesh_area mesh,
struct sldns_buffer qbuf 
)

Make space for another recursion state for a reply in the mesh.

Parameters
meshmesh area
qbufquery buffer to save if recursion is invoked to make space. This buffer is necessary, because the following sequence in calls can result in an overwrite of the incoming query: delete_other_mesh_query - iter_clean - serviced_delete - waiting udp query is sent - on error callback - callback sends SERVFAIL reply over the same network channel, and shared UDP buffer is overwritten. You can pass NULL if there is no buffer that must be backed up.
Returns
false if no space is available.

References rbtree_t::count, mesh_area::env, mesh_area::jostle_first, mesh_area::jostle_max, log_nametypeclass(), mesh_area::max_reply_states, mesh_state_delete(), mesh_walk_supers(), module_env::now_tv, mesh_area::num_reply_states, mesh_area::qbuf_bak, query_info::qclass, module_qstate::qinfo, query_info::qname, query_info::qtype, mesh_state::reply_list, module_qstate::return_msg, module_qstate::return_rcode, mesh_state::s, sldns_buffer_copy(), mesh_reply::start_time, mesh_area::stats_jostled, mesh_state::super_set, timeval_smaller(), timeval_subtract(), VERB_ALGO, and verbose().

Referenced by mesh_new_client(), and mesh_new_prefetch().

void mesh_list_insert ( struct mesh_state m,
struct mesh_state **  fp,
struct mesh_state **  lp 
)

Insert mesh state into a double linked list.

Inserted at end.

Parameters
mmesh state.
fppointer to the first-elem-pointer of the list.
lppointer to the last-elem-pointer of the list.

References mesh_state::next, and mesh_state::prev.

Referenced by mesh_new_client(), and mesh_new_prefetch().

void mesh_list_remove ( struct mesh_state m,
struct mesh_state **  fp,
struct mesh_state **  lp 
)

Remove mesh state from a double linked list.

Remove from any position.

Parameters
mmesh state.
fppointer to the first-elem-pointer of the list.
lppointer to the last-elem-pointer of the list.

References mesh_state::next, and mesh_state::prev.

Referenced by mesh_state_delete().