1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24
25 #include "curl_setup.h"
26
27 #include <curl/curl.h>
28
29 #ifdef USE_LIBPSL
30
31 #include "psl.h"
32 #include "share.h"
33
34 /* The last 3 #include files should be in this order */
35 #include "curl_printf.h"
36 #include "curl_memory.h"
37 #include "memdebug.h"
38
Curl_psl_destroy(struct PslCache * pslcache)39 void Curl_psl_destroy(struct PslCache *pslcache)
40 {
41 if(pslcache->psl) {
42 if(pslcache->dynamic)
43 psl_free((psl_ctx_t *) pslcache->psl);
44 pslcache->psl = NULL;
45 pslcache->dynamic = FALSE;
46 }
47 }
48
now_seconds(void)49 static time_t now_seconds(void)
50 {
51 struct curltime now = Curl_now();
52
53 return now.tv_sec;
54 }
55
Curl_psl_use(struct Curl_easy * easy)56 const psl_ctx_t *Curl_psl_use(struct Curl_easy *easy)
57 {
58 struct PslCache *pslcache = easy->psl;
59 const psl_ctx_t *psl;
60 time_t now;
61
62 if(!pslcache)
63 return NULL;
64
65 Curl_share_lock(easy, CURL_LOCK_DATA_PSL, CURL_LOCK_ACCESS_SHARED);
66 now = now_seconds();
67 if(!pslcache->psl || pslcache->expires <= now) {
68 /* Let a chance to other threads to do the job: avoids deadlock. */
69 Curl_share_unlock(easy, CURL_LOCK_DATA_PSL);
70
71 /* Update cache: this needs an exclusive lock. */
72 Curl_share_lock(easy, CURL_LOCK_DATA_PSL, CURL_LOCK_ACCESS_SINGLE);
73
74 /* Recheck in case another thread did the job. */
75 now = now_seconds();
76 if(!pslcache->psl || pslcache->expires <= now) {
77 bool dynamic = FALSE;
78 time_t expires = TIME_T_MAX;
79
80 #if defined(PSL_VERSION_NUMBER) && PSL_VERSION_NUMBER >= 0x001000
81 psl = psl_latest(NULL);
82 dynamic = psl != NULL;
83 /* Take care of possible time computation overflow. */
84 expires = now < TIME_T_MAX - PSL_TTL? now + PSL_TTL: TIME_T_MAX;
85
86 /* Only get the built-in PSL if we do not already have the "latest". */
87 if(!psl && !pslcache->dynamic)
88 #endif
89
90 psl = psl_builtin();
91
92 if(psl) {
93 Curl_psl_destroy(pslcache);
94 pslcache->psl = psl;
95 pslcache->dynamic = dynamic;
96 pslcache->expires = expires;
97 }
98 }
99 Curl_share_unlock(easy, CURL_LOCK_DATA_PSL); /* Release exclusive lock. */
100 Curl_share_lock(easy, CURL_LOCK_DATA_PSL, CURL_LOCK_ACCESS_SHARED);
101 }
102 psl = pslcache->psl;
103 if(!psl)
104 Curl_share_unlock(easy, CURL_LOCK_DATA_PSL);
105 return psl;
106 }
107
Curl_psl_release(struct Curl_easy * easy)108 void Curl_psl_release(struct Curl_easy *easy)
109 {
110 Curl_share_unlock(easy, CURL_LOCK_DATA_PSL);
111 }
112
113 #endif /* USE_LIBPSL */
114
