2 * Copyright (C) 2015-2020 "IoT.bzh"
3 * Author José Bollo <jose.bollo@iot.bzh>
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
9 * http://www.apache.org/licenses/LICENSE-2.0
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
18 #if WITH_DYNAMIC_BINDING
30 #include "afb-api-so.h"
31 #include "afb-api-so-v3.h"
33 #include "sig-monitor.h"
35 #if WITH_LEGACY_BINDING_V1
36 # include "afb-api-so-v1.h"
38 #if WITH_LEGACY_BINDING_VDYN
39 # include "afb-api-so-vdyn.h"
41 #if WITH_LEGACY_BINDING_V2
42 # include "afb-api-so-v2.h"
52 static void safe_dlopen_cb(int sig, void *closure)
54 struct safe_dlopen *sd = closure;
56 sd->handle = dlopen(sd->path, sd->flags);
58 ERROR("dlopen of %s raised signal %s", sd->path, strsignal(sig));
63 static void *safe_dlopen(const char *filename, int flags)
65 struct safe_dlopen sd;
69 sig_monitor(0, safe_dlopen_cb, &sd);
73 static int load_binding(const char *path, int force, struct afb_apiset *declare_set, struct afb_apiset * call_set)
78 static int dlopen_flags = 0;
80 /* compute the dlopen flags */
81 if (dlopen_flags == 0) {
82 /* For ASan mode, export AFB_NO_RTLD_DEEPBIND=1, to disable RTLD_DEEPBIND */
83 char *string = secure_getenv("AFB_NO_RTLD_DEEPBIND");
84 if (string && string[0] == '1' && string[1] == 0)
85 dlopen_flags = RTLD_NOW | RTLD_LOCAL;
87 dlopen_flags = RTLD_NOW | RTLD_LOCAL | RTLD_DEEPBIND;
90 /* set default return code rc according to force */
93 /* try to open the library */
94 handle = safe_dlopen(path, dlopen_flags);
97 ERROR("binding [%s] not loadable: %s", path, dlerror());
99 WARNING("binding [%s] not loadable: %s", path, dlerror());
103 * This is a loadable library let's check if it's a binding ...
106 /* try the version 3 */
107 rc = afb_api_so_v3_add(path, handle, declare_set, call_set);
109 /* error when loading a valid v3 binding */
113 return 0; /* yes version 3 */
115 #if WITH_LEGACY_BINDING_V2
116 /* try the version 2 */
117 rc = afb_api_so_v2_add(path, handle, declare_set, call_set);
119 /* error when loading a valid v2 binding */
123 return 0; /* yes version 2 */
125 if (dlsym(handle, "afbBindingV2")) {
126 WARNING("binding [%s]: version 2 not supported", path);
131 #if WITH_LEGACY_BINDING_VDYN
132 /* try the version dyn */
133 rc = afb_api_so_vdyn_add(path, handle, declare_set, call_set);
135 /* error when loading a valid dyn binding */
139 return 0; /* yes version dyn */
141 if (dlsym(handle, "afbBindingVdyn")) {
142 WARNING("binding [%s]: version DYN not supported", path);
147 #if WITH_LEGACY_BINDING_V1
148 /* try the version 1 */
149 rc = afb_api_so_v1_add(path, handle, declare_set, call_set);
151 /* error when loading a valid v1 binding */
155 return 0; /* yes version 1 */
157 if (dlsym(handle, "afbBindingV1Register")) {
158 WARNING("binding [%s]: version 1 not supported", path);
163 /* not a valid binding */
164 _VERBOSE_(force ? Log_Level_Error : Log_Level_Info, "binding [%s] %s",
165 path, obsolete ? "is obsolete" : "isn't an AFB binding");
174 int afb_api_so_add_binding(const char *path, struct afb_apiset *declare_set, struct afb_apiset * call_set)
176 return load_binding(path, 1, declare_set, call_set);
179 static int adddirs(char path[PATH_MAX], size_t end, struct afb_apiset *declare_set, struct afb_apiset * call_set, int failstops)
187 /* open the DIR now */
190 ERROR("can't scan binding directory %s, %m", path);
193 INFO("Scanning dir=[%s] for bindings", path);
195 /* scan each entry */
203 ERROR("read error while scanning directory %.*s: %m", (int)(end - 1), path);
207 /* get the name and inspect dereferenced link instead of the directory entry */
208 len = strlen(dent->d_name);
209 if (len + end >= PATH_MAX) {
210 ERROR("path too long while scanning bindings for %.*s%s", (int)end, path, dent->d_name);
213 memcpy(&path[end], dent->d_name, len+1);
214 rc = stat(path, &st);
216 ERROR("getting status of %s failed: %m", path);
219 else if (S_ISDIR(st.st_mode)) {
220 /* case of directories */
221 if (dent->d_name[0] == '.') {
223 Exclude from the search of bindings any
224 directory starting with a dot (.) by default.
226 It is possible to reactivate the prvious behaviour
227 by defining the following preprocessor variables
229 - AFB_API_SO_ACCEPT_DOT_PREFIXED_DIRS
231 When this variable is defined, the directories
232 starting with a dot are searched except
233 if their name is "." or ".." or ".debug"
235 - AFB_API_SO_ACCEPT_DOT_DEBUG_DIRS
237 When this variable is defined and the variable
238 AFB_API_SO_ACCEPT_DOT_PREFIXED_DIRS is also defined
239 scans any directory not being "." or "..".
241 The previous behaviour was like difining the 2 variables,
242 meaning that only . and .. were excluded from the search.
244 This change is intended to definitely solve the issue
245 SPEC-662. Yocto installed the debugging symbols in the
246 subdirectory .debug. For example the binding.so also
247 had a .debug/binding.so file attached. Opening that
248 debug file made dlopen crashing.
249 See https://sourceware.org/bugzilla/show_bug.cgi?id=22101
251 #if !defined(AFB_API_SO_ACCEPT_DOT_PREFIXED_DIRS) /* not defined by default */
252 continue; /* ignore any directory beginning with a dot */
256 if (dent->d_name[1] == '.' && len == 2)
258 #if !defined(AFB_API_SO_ACCEPT_DOT_DEBUG_DIRS) /* not defined by default */
260 && dent->d_name[1] == 'd'
261 && dent->d_name[2] == 'e'
262 && dent->d_name[3] == 'b'
263 && dent->d_name[4] == 'u'
264 && dent->d_name[5] == 'g')
265 continue; /* .debug */
269 rc = adddirs(path, end+len, declare_set, call_set, failstops);
270 } else if (S_ISREG(st.st_mode)) {
272 if (memcmp(&dent->d_name[len - 3], ".so", 4))
274 rc = load_binding(path, 0, declare_set, call_set);
276 if (rc < 0 && failstops) {
285 int afb_api_so_add_directory(const char *path, struct afb_apiset *declare_set, struct afb_apiset * call_set, int failstops)
288 char buffer[PATH_MAX];
290 length = strlen(path);
291 if (length >= sizeof(buffer)) {
292 ERROR("path too long %lu [%.99s...]", (unsigned long)length, path);
296 memcpy(buffer, path, length + 1);
297 return adddirs(buffer, length, declare_set, call_set, failstops);
300 int afb_api_so_add_path(const char *path, struct afb_apiset *declare_set, struct afb_apiset * call_set, int failstops)
305 rc = stat(path, &st);
307 ERROR("Invalid binding path [%s]: %m", path);
308 else if (S_ISDIR(st.st_mode))
309 rc = afb_api_so_add_directory(path, declare_set, call_set, failstops);
310 else if (strstr(path, ".so"))
311 rc = load_binding(path, 0, declare_set, call_set);
313 INFO("not a binding [%s], skipped", path);
317 int afb_api_so_add_pathset(const char *pathset, struct afb_apiset *declare_set, struct afb_apiset * call_set, int failstops)
319 static char sep[] = ":";
323 ps = strdupa(pathset);
325 p = strsep(&ps, sep);
328 rc = afb_api_so_add_path(p, declare_set, call_set, failstops);
334 int afb_api_so_add_pathset_fails(const char *pathset, struct afb_apiset *declare_set, struct afb_apiset * call_set)
336 return afb_api_so_add_pathset(pathset, declare_set, call_set, 1);
339 int afb_api_so_add_pathset_nofails(const char *pathset, struct afb_apiset *declare_set, struct afb_apiset * call_set)
341 return afb_api_so_add_pathset(pathset, declare_set, call_set, 0);