1 /*
2 * Copyright 2015-2022 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 /*
11 * Without this we start getting longjmp crashes because it thinks we're jumping
12 * up the stack when in fact we are jumping to an entirely different stack. The
13 * cost of this is not having certain buffer overrun/underrun checks etc for
14 * this source file :-(
15 */
16 #undef _FORTIFY_SOURCE
17
18 /* This must be the first #include file */
19 #include "async_local.h"
20
21 #include <openssl/err.h>
22 #include "crypto/cryptlib.h"
23 #include <string.h>
24
25 #define ASYNC_JOB_RUNNING 0
26 #define ASYNC_JOB_PAUSING 1
27 #define ASYNC_JOB_PAUSED 2
28 #define ASYNC_JOB_STOPPING 3
29
30 static CRYPTO_THREAD_LOCAL ctxkey;
31 static CRYPTO_THREAD_LOCAL poolkey;
32
33 static void async_delete_thread_state(void *arg);
34
async_ctx_new(void)35 static async_ctx *async_ctx_new(void)
36 {
37 async_ctx *nctx;
38
39 if (!ossl_init_thread_start(NULL, NULL, async_delete_thread_state))
40 return NULL;
41
42 nctx = OPENSSL_malloc(sizeof(*nctx));
43 if (nctx == NULL)
44 goto err;
45
46 async_fibre_init_dispatcher(&nctx->dispatcher);
47 nctx->currjob = NULL;
48 nctx->blocked = 0;
49 if (!CRYPTO_THREAD_set_local(&ctxkey, nctx))
50 goto err;
51
52 return nctx;
53 err:
54 OPENSSL_free(nctx);
55
56 return NULL;
57 }
58
async_get_ctx(void)59 async_ctx *async_get_ctx(void)
60 {
61 return (async_ctx *)CRYPTO_THREAD_get_local(&ctxkey);
62 }
63
async_ctx_free(void)64 static int async_ctx_free(void)
65 {
66 async_ctx *ctx;
67
68 ctx = async_get_ctx();
69
70 if (!CRYPTO_THREAD_set_local(&ctxkey, NULL))
71 return 0;
72
73 OPENSSL_free(ctx);
74
75 return 1;
76 }
77
async_job_new(void)78 static ASYNC_JOB *async_job_new(void)
79 {
80 ASYNC_JOB *job = NULL;
81
82 job = OPENSSL_zalloc(sizeof(*job));
83 if (job == NULL)
84 return NULL;
85
86 job->status = ASYNC_JOB_RUNNING;
87
88 return job;
89 }
90
async_job_free(ASYNC_JOB * job)91 static void async_job_free(ASYNC_JOB *job)
92 {
93 if (job != NULL) {
94 OPENSSL_free(job->funcargs);
95 async_fibre_free(&job->fibrectx);
96 OPENSSL_free(job);
97 }
98 }
99
async_get_pool_job(void)100 static ASYNC_JOB *async_get_pool_job(void) {
101 ASYNC_JOB *job;
102 async_pool *pool;
103
104 pool = (async_pool *)CRYPTO_THREAD_get_local(&poolkey);
105 if (pool == NULL) {
106 /*
107 * Pool has not been initialised, so init with the defaults, i.e.
108 * no max size and no pre-created jobs
109 */
110 if (ASYNC_init_thread(0, 0) == 0)
111 return NULL;
112 pool = (async_pool *)CRYPTO_THREAD_get_local(&poolkey);
113 }
114
115 job = sk_ASYNC_JOB_pop(pool->jobs);
116 if (job == NULL) {
117 /* Pool is empty */
118 if ((pool->max_size != 0) && (pool->curr_size >= pool->max_size))
119 return NULL;
120
121 job = async_job_new();
122 if (job != NULL) {
123 if (! async_fibre_makecontext(&job->fibrectx)) {
124 async_job_free(job);
125 return NULL;
126 }
127 pool->curr_size++;
128 }
129 }
130 return job;
131 }
132
async_release_job(ASYNC_JOB * job)133 static void async_release_job(ASYNC_JOB *job) {
134 async_pool *pool;
135
136 pool = (async_pool *)CRYPTO_THREAD_get_local(&poolkey);
137 if (pool == NULL) {
138 ERR_raise(ERR_LIB_ASYNC, ERR_R_INTERNAL_ERROR);
139 return;
140 }
141 OPENSSL_free(job->funcargs);
142 job->funcargs = NULL;
143 sk_ASYNC_JOB_push(pool->jobs, job);
144 }
145
async_start_func(void)146 void async_start_func(void)
147 {
148 ASYNC_JOB *job;
149 async_ctx *ctx = async_get_ctx();
150
151 if (ctx == NULL) {
152 ERR_raise(ERR_LIB_ASYNC, ERR_R_INTERNAL_ERROR);
153 return;
154 }
155 while (1) {
156 /* Run the job */
157 job = ctx->currjob;
158 job->ret = job->func(job->funcargs);
159
160 /* Stop the job */
161 job->status = ASYNC_JOB_STOPPING;
162 if (!async_fibre_swapcontext(&job->fibrectx,
163 &ctx->dispatcher, 1)) {
164 /*
165 * Should not happen. Getting here will close the thread...can't do
166 * much about it
167 */
168 ERR_raise(ERR_LIB_ASYNC, ASYNC_R_FAILED_TO_SWAP_CONTEXT);
169 }
170 }
171 }
172
ASYNC_start_job(ASYNC_JOB ** job,ASYNC_WAIT_CTX * wctx,int * ret,int (* func)(void *),void * args,size_t size)173 int ASYNC_start_job(ASYNC_JOB **job, ASYNC_WAIT_CTX *wctx, int *ret,
174 int (*func)(void *), void *args, size_t size)
175 {
176 async_ctx *ctx;
177 OSSL_LIB_CTX *libctx;
178
179 if (!OPENSSL_init_crypto(OPENSSL_INIT_ASYNC, NULL))
180 return ASYNC_ERR;
181
182 ctx = async_get_ctx();
183 if (ctx == NULL)
184 ctx = async_ctx_new();
185 if (ctx == NULL)
186 return ASYNC_ERR;
187
188 if (*job != NULL)
189 ctx->currjob = *job;
190
191 for (;;) {
192 if (ctx->currjob != NULL) {
193 if (ctx->currjob->status == ASYNC_JOB_STOPPING) {
194 *ret = ctx->currjob->ret;
195 ctx->currjob->waitctx = NULL;
196 async_release_job(ctx->currjob);
197 ctx->currjob = NULL;
198 *job = NULL;
199 return ASYNC_FINISH;
200 }
201
202 if (ctx->currjob->status == ASYNC_JOB_PAUSING) {
203 *job = ctx->currjob;
204 ctx->currjob->status = ASYNC_JOB_PAUSED;
205 ctx->currjob = NULL;
206 return ASYNC_PAUSE;
207 }
208
209 if (ctx->currjob->status == ASYNC_JOB_PAUSED) {
210 if (*job == NULL)
211 return ASYNC_ERR;
212 ctx->currjob = *job;
213
214 /*
215 * Restore the default libctx to what it was the last time the
216 * fibre ran
217 */
218 libctx = OSSL_LIB_CTX_set0_default(ctx->currjob->libctx);
219 if (libctx == NULL) {
220 /* Failed to set the default context */
221 ERR_raise(ERR_LIB_ASYNC, ERR_R_INTERNAL_ERROR);
222 goto err;
223 }
224 /* Resume previous job */
225 if (!async_fibre_swapcontext(&ctx->dispatcher,
226 &ctx->currjob->fibrectx, 1)) {
227 ctx->currjob->libctx = OSSL_LIB_CTX_set0_default(libctx);
228 ERR_raise(ERR_LIB_ASYNC, ASYNC_R_FAILED_TO_SWAP_CONTEXT);
229 goto err;
230 }
231 /*
232 * In case the fibre changed the default libctx we set it back
233 * again to what it was originally, and remember what it had
234 * been changed to.
235 */
236 ctx->currjob->libctx = OSSL_LIB_CTX_set0_default(libctx);
237 continue;
238 }
239
240 /* Should not happen */
241 ERR_raise(ERR_LIB_ASYNC, ERR_R_INTERNAL_ERROR);
242 async_release_job(ctx->currjob);
243 ctx->currjob = NULL;
244 *job = NULL;
245 return ASYNC_ERR;
246 }
247
248 /* Start a new job */
249 if ((ctx->currjob = async_get_pool_job()) == NULL)
250 return ASYNC_NO_JOBS;
251
252 if (args != NULL) {
253 ctx->currjob->funcargs = OPENSSL_malloc(size);
254 if (ctx->currjob->funcargs == NULL) {
255 async_release_job(ctx->currjob);
256 ctx->currjob = NULL;
257 return ASYNC_ERR;
258 }
259 memcpy(ctx->currjob->funcargs, args, size);
260 } else {
261 ctx->currjob->funcargs = NULL;
262 }
263
264 ctx->currjob->func = func;
265 ctx->currjob->waitctx = wctx;
266 libctx = ossl_lib_ctx_get_concrete(NULL);
267 if (!async_fibre_swapcontext(&ctx->dispatcher,
268 &ctx->currjob->fibrectx, 1)) {
269 ERR_raise(ERR_LIB_ASYNC, ASYNC_R_FAILED_TO_SWAP_CONTEXT);
270 goto err;
271 }
272 /*
273 * In case the fibre changed the default libctx we set it back again
274 * to what it was, and remember what it had been changed to.
275 */
276 ctx->currjob->libctx = OSSL_LIB_CTX_set0_default(libctx);
277 }
278
279 err:
280 async_release_job(ctx->currjob);
281 ctx->currjob = NULL;
282 *job = NULL;
283 return ASYNC_ERR;
284 }
285
ASYNC_pause_job(void)286 int ASYNC_pause_job(void)
287 {
288 ASYNC_JOB *job;
289 async_ctx *ctx = async_get_ctx();
290
291 if (ctx == NULL
292 || ctx->currjob == NULL
293 || ctx->blocked) {
294 /*
295 * Could be we've deliberately not been started within a job so this is
296 * counted as success.
297 */
298 return 1;
299 }
300
301 job = ctx->currjob;
302 job->status = ASYNC_JOB_PAUSING;
303
304 if (!async_fibre_swapcontext(&job->fibrectx,
305 &ctx->dispatcher, 1)) {
306 ERR_raise(ERR_LIB_ASYNC, ASYNC_R_FAILED_TO_SWAP_CONTEXT);
307 return 0;
308 }
309 /* Reset counts of added and deleted fds */
310 async_wait_ctx_reset_counts(job->waitctx);
311
312 return 1;
313 }
314
async_empty_pool(async_pool * pool)315 static void async_empty_pool(async_pool *pool)
316 {
317 ASYNC_JOB *job;
318
319 if (pool == NULL || pool->jobs == NULL)
320 return;
321
322 do {
323 job = sk_ASYNC_JOB_pop(pool->jobs);
324 async_job_free(job);
325 } while (job);
326 }
327
async_init(void)328 int async_init(void)
329 {
330 if (!CRYPTO_THREAD_init_local(&ctxkey, NULL))
331 return 0;
332
333 if (!CRYPTO_THREAD_init_local(&poolkey, NULL)) {
334 CRYPTO_THREAD_cleanup_local(&ctxkey);
335 return 0;
336 }
337
338 return async_local_init();
339 }
340
async_deinit(void)341 void async_deinit(void)
342 {
343 CRYPTO_THREAD_cleanup_local(&ctxkey);
344 CRYPTO_THREAD_cleanup_local(&poolkey);
345 async_local_deinit();
346 }
347
ASYNC_init_thread(size_t max_size,size_t init_size)348 int ASYNC_init_thread(size_t max_size, size_t init_size)
349 {
350 async_pool *pool;
351 size_t curr_size = 0;
352
353 if (init_size > max_size) {
354 ERR_raise(ERR_LIB_ASYNC, ASYNC_R_INVALID_POOL_SIZE);
355 return 0;
356 }
357
358 if (!OPENSSL_init_crypto(OPENSSL_INIT_ASYNC, NULL))
359 return 0;
360
361 if (!ossl_init_thread_start(NULL, NULL, async_delete_thread_state))
362 return 0;
363
364 pool = OPENSSL_zalloc(sizeof(*pool));
365 if (pool == NULL)
366 return 0;
367
368 pool->jobs = sk_ASYNC_JOB_new_reserve(NULL, init_size);
369 if (pool->jobs == NULL) {
370 ERR_raise(ERR_LIB_ASYNC, ERR_R_CRYPTO_LIB);
371 OPENSSL_free(pool);
372 return 0;
373 }
374
375 pool->max_size = max_size;
376
377 /* Pre-create jobs as required */
378 while (init_size--) {
379 ASYNC_JOB *job;
380 job = async_job_new();
381 if (job == NULL || !async_fibre_makecontext(&job->fibrectx)) {
382 /*
383 * Not actually fatal because we already created the pool, just
384 * skip creation of any more jobs
385 */
386 async_job_free(job);
387 break;
388 }
389 job->funcargs = NULL;
390 sk_ASYNC_JOB_push(pool->jobs, job); /* Cannot fail due to reserve */
391 curr_size++;
392 }
393 pool->curr_size = curr_size;
394 if (!CRYPTO_THREAD_set_local(&poolkey, pool)) {
395 ERR_raise(ERR_LIB_ASYNC, ASYNC_R_FAILED_TO_SET_POOL);
396 goto err;
397 }
398
399 return 1;
400 err:
401 async_empty_pool(pool);
402 sk_ASYNC_JOB_free(pool->jobs);
403 OPENSSL_free(pool);
404 return 0;
405 }
406
async_delete_thread_state(void * arg)407 static void async_delete_thread_state(void *arg)
408 {
409 async_pool *pool = (async_pool *)CRYPTO_THREAD_get_local(&poolkey);
410
411 if (pool != NULL) {
412 async_empty_pool(pool);
413 sk_ASYNC_JOB_free(pool->jobs);
414 OPENSSL_free(pool);
415 CRYPTO_THREAD_set_local(&poolkey, NULL);
416 }
417 async_local_cleanup();
418 async_ctx_free();
419 }
420
ASYNC_cleanup_thread(void)421 void ASYNC_cleanup_thread(void)
422 {
423 if (!OPENSSL_init_crypto(OPENSSL_INIT_ASYNC, NULL))
424 return;
425
426 async_delete_thread_state(NULL);
427 }
428
ASYNC_get_current_job(void)429 ASYNC_JOB *ASYNC_get_current_job(void)
430 {
431 async_ctx *ctx;
432
433 if (!OPENSSL_init_crypto(OPENSSL_INIT_ASYNC, NULL))
434 return NULL;
435
436 ctx = async_get_ctx();
437 if (ctx == NULL)
438 return NULL;
439
440 return ctx->currjob;
441 }
442
ASYNC_get_wait_ctx(ASYNC_JOB * job)443 ASYNC_WAIT_CTX *ASYNC_get_wait_ctx(ASYNC_JOB *job)
444 {
445 return job->waitctx;
446 }
447
ASYNC_block_pause(void)448 void ASYNC_block_pause(void)
449 {
450 async_ctx *ctx;
451
452 if (!OPENSSL_init_crypto(OPENSSL_INIT_ASYNC, NULL))
453 return;
454
455 ctx = async_get_ctx();
456 if (ctx == NULL || ctx->currjob == NULL) {
457 /*
458 * We're not in a job anyway so ignore this
459 */
460 return;
461 }
462 ctx->blocked++;
463 }
464
ASYNC_unblock_pause(void)465 void ASYNC_unblock_pause(void)
466 {
467 async_ctx *ctx;
468
469 if (!OPENSSL_init_crypto(OPENSSL_INIT_ASYNC, NULL))
470 return;
471
472 ctx = async_get_ctx();
473 if (ctx == NULL || ctx->currjob == NULL) {
474 /*
475 * We're not in a job anyway so ignore this
476 */
477 return;
478 }
479 if (ctx->blocked > 0)
480 ctx->blocked--;
481 }
482
