1 /* authd/provider.c - authentication provider framework
2 * Copyright (c) 2016 Elizabeth Myers <elizabeth@interlinked.me>
4 * Permission to use, copy, modify, and/or distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice is present in all copies.
8 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
9 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
10 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
11 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
12 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
13 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
14 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
15 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
16 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
17 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
18 * POSSIBILITY OF SUCH DAMAGE.
21 /* The basic design here is to have "authentication providers" that do things
22 * like query ident and blacklists and even open proxies.
24 * Providers are registered in the auth_providers linked list. It is planned to
25 * use a bitmap to store provider ID's later.
27 * Providers can either return failure immediately, immediate acceptance, or do
28 * work in the background (calling set_provider to signal this).
30 * Provider-specific data for each client can be kept in an index of the data
31 * struct member (using the provider's ID).
33 * All providers must implement at a minimum a perform_provider function. You
34 * don't have to implement the others if you don't need them.
36 * Providers may kick clients off by rejecting them. Upon rejection, all
37 * providers are cancelled. They can also unconditionally accept them.
39 * When a provider is done and is neutral on accepting/rejecting a client, it
40 * should call provider_done. Do NOT call this if you have accepted or rejected
43 * Eventually, stuff like *:line handling will be moved here, but that means we
44 * have to talk to bandb directly first.
46 * --Elizafox, 9 March 2016
50 #include "rb_dictionary.h"
55 static EVH provider_timeout_event
;
57 rb_dictionary
*auth_clients
;
58 rb_dictionary
*auth_providers
; /* Referenced by name */
60 static rb_dlink_list free_pids
;
62 static struct ev_entry
*timeout_ev
;
64 /* Initalise all providers */
68 auth_clients
= rb_dictionary_create("pending auth clients", rb_uint32cmp
);
69 auth_providers
= rb_dictionary_create("auth providers", strcmp
);
70 timeout_ev
= rb_event_addish("provider_timeout_event", provider_timeout_event
, NULL
, 1);
72 load_provider(&rdns_provider
);
73 load_provider(&ident_provider
);
74 load_provider(&blacklist_provider
);
75 load_provider(&opm_provider
);
78 /* Terminate all providers */
80 destroy_providers(void)
83 rb_dictionary_iter iter
;
84 struct auth_client
*auth
;
85 struct auth_provider
*provider
;
87 /* Cancel outstanding connections */
88 RB_DICTIONARY_FOREACH(auth
, &iter
, auth_clients
)
90 /* TBD - is this the right thing? */
91 reject_client(auth
, UINT32_MAX
, "destroy",
92 "Authentication system is down... try reconnecting in a few seconds");
95 RB_DICTIONARY_FOREACH(provider
, &iter
, auth_providers
)
101 rb_dictionary_destroy(auth_clients
, NULL
, NULL
);
102 rb_dictionary_destroy(auth_providers
, NULL
, NULL
);
103 rb_event_delete(timeout_ev
);
106 /* Load a provider */
108 load_provider(struct auth_provider
*provider
)
111 if(rb_dlink_list_length(&free_pids
) > 0)
113 /* use the free list */
114 provider
->id
= RB_POINTER_TO_UINT(free_pids
.head
->data
);
115 rb_dlinkDestroy(free_pids
.head
, &free_pids
);
119 if(pid
== UINT32_MAX
)
121 /* If this happens, well, I don't know what to say. Probably a bug.
122 * In any case, UINT32_MAX is a special sentinel. */
123 warn_opers(L_WARN
, "Cannot load additional provider, max reached!");
127 provider
->id
= pid
++;
130 if(provider
->opt_handlers
!= NULL
)
132 struct auth_opts_handler
*handler
;
134 for(handler
= provider
->opt_handlers
; handler
->option
!= NULL
; handler
++)
135 rb_dictionary_add(authd_option_handlers
, handler
->option
, handler
);
138 if(provider
->stats_handler
.letter
!= '\0')
139 authd_stat_handlers
[provider
->stats_handler
.letter
] = provider
->stats_handler
.handler
;
141 if(provider
->init
!= NULL
)
144 rb_dictionary_add(auth_providers
, provider
->name
, provider
);
148 unload_provider(struct auth_provider
*provider
)
150 if(provider
->opt_handlers
!= NULL
)
152 struct auth_opts_handler
*handler
;
154 for(handler
= provider
->opt_handlers
; handler
->option
!= NULL
; handler
++)
155 rb_dictionary_delete(authd_option_handlers
, handler
->option
);
158 if(provider
->stats_handler
.letter
!= '\0')
159 authd_stat_handlers
[provider
->stats_handler
.letter
] = NULL
;
161 if(provider
->destroy
!= NULL
)
164 rb_dictionary_delete(auth_providers
, provider
->name
);
167 rb_dlinkAddAlloc(RB_UINT_TO_POINTER(provider
->id
), &free_pids
);
171 /* Cancel outstanding providers for a client (if any) and free the auth instance
172 * WARNING: do not use auth instance after calling! */
174 cancel_providers(struct auth_client
*auth
)
176 if(auth
->refcount
> 0)
178 rb_dictionary_iter iter
;
179 struct auth_provider
*provider
;
181 RB_DICTIONARY_FOREACH(provider
, &iter
, auth_providers
)
183 if(provider
->cancel
!= NULL
&& is_provider_running(auth
, provider
->id
))
184 /* Cancel if required */
185 provider
->cancel(auth
);
189 rb_dictionary_delete(auth_clients
, RB_UINT_TO_POINTER(auth
->cid
));
195 * WARNING: do not use auth instance after calling! */
197 provider_done(struct auth_client
*auth
, uint32_t id
)
199 rb_dictionary_iter iter
;
200 struct auth_provider
*provider
;
202 lrb_assert(is_provider_running(auth
, id
));
203 lrb_assert(id
!= UINT32_MAX
);
204 lrb_assert(id
<= pid
);
206 set_provider_done(auth
, id
);
208 if(auth
->refcount
== 0 && !auth
->providers_starting
)
211 accept_client(auth
, id
);
215 RB_DICTIONARY_FOREACH(provider
, &iter
, auth_providers
)
217 if(provider
->completed
!= NULL
&& is_provider_running(auth
, provider
->id
))
218 /* Notify pending clients who asked for it */
219 provider
->completed(auth
, id
);
223 /* Reject a client and cancel any outstanding providers
224 * WARNING: do not use auth instance after calling! */
226 reject_client(struct auth_client
*auth
, uint32_t id
, const char *data
, const char *fmt
, ...)
228 unsigned int refcount
= auth
->refcount
;
233 vsnprintf(buf
, sizeof(buf
), fmt
, args
);
236 /* We send back username and hostname in case ircd wants to overrule our decision.
237 * In the future this may not be the case.
240 rb_helper_write(authd_helper
, "R %x %c %s %s %s :%s",
241 auth
->cid
, auth
->data
[id
].provider
->letter
,
242 auth
->username
, auth
->hostname
,
243 data
== NULL
? "*" : data
, buf
);
246 set_provider_done(auth
, id
);
248 cancel_providers(auth
);
251 /* Accept a client and cancel outstanding providers if any
252 * WARNING: do not use auth instance after calling! */
254 accept_client(struct auth_client
*auth
, uint32_t id
)
256 unsigned int refcount
= auth
->refcount
;
258 rb_helper_write(authd_helper
, "A %x %s %s", auth
->cid
, auth
->username
, auth
->hostname
);
261 set_provider_done(auth
, id
);
263 cancel_providers(auth
);
266 /* Begin authenticating user */
268 start_auth(const char *cid
, const char *l_ip
, const char *l_port
, const char *c_ip
, const char *c_port
)
270 struct auth_provider
*provider
;
271 struct auth_client
*auth
= rb_malloc(sizeof(struct auth_client
));
272 long lcid
= strtol(cid
, NULL
, 16);
273 rb_dictionary_iter iter
;
275 if(lcid
>= UINT32_MAX
)
278 auth
->cid
= (uint32_t)lcid
;
280 if(rb_dictionary_find(auth_clients
, RB_UINT_TO_POINTER(auth
->cid
)) == NULL
)
281 rb_dictionary_add(auth_clients
, RB_UINT_TO_POINTER(auth
->cid
), auth
);
284 warn_opers(L_CRIT
, "provider: duplicate client added via start_auth: %x", auth
->cid
);
285 exit(EX_PROVIDER_ERROR
);
288 rb_strlcpy(auth
->l_ip
, l_ip
, sizeof(auth
->l_ip
));
289 auth
->l_port
= (uint16_t)atoi(l_port
); /* should be safe */
290 (void) rb_inet_pton_sock(l_ip
, (struct sockaddr
*)&auth
->l_addr
);
291 SET_SS_PORT(&auth
->l_addr
, htons(auth
->l_port
));
293 rb_strlcpy(auth
->c_ip
, c_ip
, sizeof(auth
->c_ip
));
294 auth
->c_port
= (uint16_t)atoi(c_port
);
295 (void) rb_inet_pton_sock(c_ip
, (struct sockaddr
*)&auth
->c_addr
);
296 SET_SS_PORT(&auth
->c_addr
, htons(auth
->c_port
));
298 rb_strlcpy(auth
->hostname
, "*", sizeof(auth
->hostname
));
299 rb_strlcpy(auth
->username
, "*", sizeof(auth
->username
));
301 auth
->data
= rb_malloc(rb_dictionary_size(auth_providers
) *
302 sizeof(struct auth_client_data
));
304 auth
->providers_starting
= true;
305 RB_DICTIONARY_FOREACH(provider
, &iter
, auth_providers
)
307 auth
->data
[provider
->id
].provider
= provider
;
309 lrb_assert(provider
->start
!= NULL
);
311 /* Execute providers */
312 if(!provider
->start(auth
))
313 /* Rejected immediately */
316 auth
->providers_starting
= false;
318 /* If no providers are running, accept the client */
319 if(auth
->refcount
== 0)
320 accept_client(auth
, UINT32_MAX
);
323 /* Callback for the initiation */
325 handle_new_connection(int parc
, char *parv
[])
329 warn_opers(L_CRIT
, "provider: received too few params for new connection (6 expected, got %d)", parc
);
330 exit(EX_PROVIDER_ERROR
);
333 start_auth(parv
[1], parv
[2], parv
[3], parv
[4], parv
[5]);
337 handle_cancel_connection(int parc
, char *parv
[])
339 struct auth_client
*auth
;
344 warn_opers(L_CRIT
, "provider: received too few params for new connection (2 expected, got %d)", parc
);
345 exit(EX_PROVIDER_ERROR
);
348 if((lcid
= strtol(parv
[1], NULL
, 16)) > UINT32_MAX
)
350 warn_opers(L_CRIT
, "provider: got a request to cancel a connection that can't exist: %lx", lcid
);
351 exit(EX_PROVIDER_ERROR
);
354 if((auth
= rb_dictionary_retrieve(auth_clients
, RB_UINT_TO_POINTER((uint32_t)lcid
))) == NULL
)
356 /* This could happen as a race if we've accepted/rejected but they cancel, so don't die here.
361 cancel_providers(auth
);
365 provider_timeout_event(void *notused __unused
)
367 struct auth_client
*auth
;
368 rb_dictionary_iter iter
;
369 const time_t curtime
= rb_current_time();
371 RB_DICTIONARY_FOREACH(auth
, &iter
, auth_clients
)
373 rb_dictionary_iter iter2
;
374 struct auth_provider
*provider
;
376 RB_DICTIONARY_FOREACH(provider
, &iter2
, auth_providers
)
378 const time_t timeout
= get_provider_timeout(auth
, provider
->id
);
380 if(is_provider_running(auth
, provider
->id
) && provider
->timeout
!= NULL
&&
381 timeout
> 0 && timeout
< curtime
)
383 provider
->timeout(auth
);