2 * Copyright (c) 2010, 2012-2013 Todd C. Miller <Todd.Miller@courtesan.com>
4 * Permission to use, copy, modify, and 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 appear in all copies.
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21 #include <sys/types.h>
31 #endif /* STDC_HEADERS */
34 #endif /* HAVE_STRING_H */
37 #endif /* HAVE_STRINGS_H */
40 #include "compat/dlfcn.h"
45 * Emulate dlopen() using shl_load().
50 # define DYNAMIC_PATH 0
54 sudo_dlopen(const char *path, int mode)
56 int flags = DYNAMIC_PATH | BIND_VERBOSE;
59 mode = RTLD_LAZY; /* default behavior */
61 /* We don't support RTLD_GLOBAL or RTLD_LOCAL yet. */
62 if (ISSET(mode, RTLD_LAZY))
63 flags |= BIND_DEFERRED;
64 if (ISSET(mode, RTLD_NOW))
65 flags |= BIND_IMMEDIATE;
67 return (void *)shl_load(path, flags, 0L);
71 sudo_dlclose(void *handle)
73 return shl_unload((shl_t)handle);
77 sudo_dlsym(void *vhandle, const char *symbol)
79 shl_t handle = vhandle;
83 * Note that the behavior of of RTLD_NEXT and RTLD_SELF
84 * differs from most implementations when called from
87 if (vhandle == RTLD_NEXT) {
88 /* Iterate over all shared libs looking for symbol. */
89 struct shl_descriptor *desc;
91 while (shl_get(idx++, &desc) == 0) {
92 if (shl_findsym(&desc->handle, symbol, TYPE_UNDEFINED, &value) == 0)
96 if (vhandle == RTLD_DEFAULT)
98 else if (vhandle == RTLD_SELF)
100 (void)shl_findsym(&handle, symbol, TYPE_UNDEFINED, &value);
109 return strerror(errno);
112 #else /* !HAVE_SHL_LOAD */
115 * Emulate dlopen() using a static list of symbols compiled into sudo.
118 struct sudo_preload_table {
122 extern struct sudo_preload_table sudo_preload_table[];
125 sudo_dlopen(const char *path, int mode)
131 sudo_dlclose(void *handle)
137 sudo_dlsym(void *handle, const char *symbol)
139 struct sudo_preload_table *sym;
141 if (symbol != RTLD_NEXT && symbol != RTLD_DEFAULT && symbol != RTLD_SELF) {
142 for (sym = sudo_preload_table; sym->name != NULL; sym++) {
143 if (strcmp(symbol, sym->name) == 0)
153 return strerror(errno);
155 #endif /* HAVE_SHL_LOAD */
156 #endif /* HAVE_DLOPEN */