1 /*
2 script.c -- call an external script
3 Copyright (C) 1999-2005 Ivo Timmermans,
4 2000-2018 Guus Sliepen <guus@tinc-vpn.org>
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License along
17 with this program; if not, write to the Free Software Foundation, Inc.,
18 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19 */
20
21 #include "system.h"
22
23 #include "conf.h"
24 #include "device.h"
25 #include "logger.h"
26 #include "names.h"
27 #include "script.h"
28 #include "xalloc.h"
29
30 #ifdef HAVE_PUTENV
unputenv(const char * p)31 static void unputenv(const char *p) {
32 const char *e = strchr(p, '=');
33
34 if(!e) {
35 return;
36 }
37
38 int len = e - p;
39 #ifndef HAVE_UNSETENV
40 #ifdef HAVE_MINGW
41 // Windows requires putenv("FOO=") to unset %FOO%
42 len++;
43 #endif
44 #endif
45 char var[len + 1];
46 strncpy(var, p, len);
47 var[len] = 0;
48 #ifdef HAVE_UNSETENV
49 unsetenv(var);
50 #else
51 // We must keep what we putenv() around in memory.
52 // To do this without memory leaks, keep things in a list and reuse if possible.
53 static list_t list = {0};
54
55 for list_each(char, data, &list) {
56 if(!strcmp(data, var)) {
57 putenv(data);
58 return;
59 }
60 }
61
62 char *data = xstrdup(var);
63 list_insert_tail(&list, data);
64 putenv(data);
65 #endif
66 }
67 #else
putenv(const char * p)68 static void putenv(const char *p) {}
unputenv(const char * p)69 static void unputenv(const char *p) {}
70 #endif
71
72 static const int min_env_size = 10;
73
environment_add(environment_t * env,const char * format,...)74 int environment_add(environment_t *env, const char *format, ...) {
75 if(env->n >= env->size) {
76 env->size = env->n ? env->n * 2 : min_env_size;
77 env->entries = xrealloc(env->entries, env->size * sizeof(*env->entries));
78 }
79
80 if(format) {
81 va_list ap;
82 va_start(ap, format);
83 vasprintf(&env->entries[env->n], format, ap);
84 va_end(ap);
85 } else {
86 env->entries[env->n] = NULL;
87 }
88
89 return env->n++;
90 }
91
environment_update(environment_t * env,int pos,const char * format,...)92 void environment_update(environment_t *env, int pos, const char *format, ...) {
93 free(env->entries[pos]);
94 va_list ap;
95 va_start(ap, format);
96 vasprintf(&env->entries[pos], format, ap);
97 va_end(ap);
98 }
99
environment_init(environment_t * env)100 void environment_init(environment_t *env) {
101 env->n = 0;
102 env->size = min_env_size;
103 env->entries = xzalloc(env->size * sizeof(*env->entries));
104
105 if(netname) {
106 environment_add(env, "NETNAME=%s", netname);
107 }
108
109 if(myname) {
110 environment_add(env, "NAME=%s", myname);
111 }
112
113 if(device) {
114 environment_add(env, "DEVICE=%s", device);
115 }
116
117 if(iface) {
118 environment_add(env, "INTERFACE=%s", iface);
119 }
120
121 if(debug_level >= 0) {
122 environment_add(env, "DEBUG=%d", debug_level);
123 }
124 }
125
environment_exit(environment_t * env)126 void environment_exit(environment_t *env) {
127 for(int i = 0; i < env->n; i++) {
128 free(env->entries[i]);
129 }
130
131 free(env->entries);
132 }
133
execute_script(const char * name,environment_t * env)134 bool execute_script(const char *name, environment_t *env) {
135 char scriptname[PATH_MAX];
136 char *command;
137
138 snprintf(scriptname, sizeof(scriptname), "%s" SLASH "%s%s", confbase, name, scriptextension);
139
140 /* First check if there is a script */
141
142 #ifdef HAVE_MINGW
143
144 if(!*scriptextension) {
145 const char *pathext = getenv("PATHEXT");
146
147 if(!pathext) {
148 pathext = ".COM;.EXE;.BAT;.CMD";
149 }
150
151 size_t pathlen = strlen(pathext);
152 size_t scriptlen = strlen(scriptname);
153 char fullname[scriptlen + pathlen + 1];
154 char *ext = fullname + scriptlen;
155 strncpy(fullname, scriptname, sizeof(fullname));
156
157 const char *p = pathext;
158 bool found = false;
159
160 while(p && *p) {
161 const char *q = strchr(p, ';');
162
163 if(q) {
164 memcpy(ext, p, q - p);
165 ext[q - p] = 0;
166 q++;
167 } else {
168 strncpy(ext, p, pathlen + 1);
169 }
170
171 if((found = !access(fullname, F_OK))) {
172 break;
173 }
174
175 p = q;
176 }
177
178 if(!found) {
179 return true;
180 }
181 } else
182 #endif
183
184 if(access(scriptname, F_OK)) {
185 return true;
186 }
187
188 logger(DEBUG_STATUS, LOG_INFO, "Executing script %s", name);
189
190 /* Set environment */
191
192 for(int i = 0; i < env->n; i++) {
193 putenv(env->entries[i]);
194 }
195
196 if(scriptinterpreter) {
197 xasprintf(&command, "%s \"%s\"", scriptinterpreter, scriptname);
198 } else {
199 xasprintf(&command, "\"%s\"", scriptname);
200 }
201
202 int status = system(command);
203
204 free(command);
205
206 /* Unset environment */
207
208 for(int i = 0; i < env->n; i++) {
209 unputenv(env->entries[i]);
210 }
211
212 if(status != -1) {
213 #ifdef WEXITSTATUS
214
215 if(WIFEXITED(status)) { /* Child exited by itself */
216 if(WEXITSTATUS(status)) {
217 logger(DEBUG_ALWAYS, LOG_ERR, "Script %s exited with non-zero status %d",
218 name, WEXITSTATUS(status));
219 return false;
220 }
221 } else if(WIFSIGNALED(status)) { /* Child was killed by a signal */
222 logger(DEBUG_ALWAYS, LOG_ERR, "Script %s was killed by signal %d (%s)",
223 name, WTERMSIG(status), strsignal(WTERMSIG(status)));
224 return false;
225 } else { /* Something strange happened */
226 logger(DEBUG_ALWAYS, LOG_ERR, "Script %s terminated abnormally", name);
227 return false;
228 }
229
230 #endif
231 } else {
232 logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "system", strerror(errno));
233 return false;
234 }
235
236 return true;
237 }
238