1 /*
2  * SPDX-License-Identifier: ISC
3  *
4  * Copyright (c) 2000-2005, 2007-2019
5  *	Todd C. Miller <Todd.Miller@sudo.ws>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  *
19  * Sponsored in part by the Defense Advanced Research Projects
20  * Agency (DARPA) and Air Force Research Laboratory, Air Force
21  * Materiel Command, USAF, under agreement number F39502-99-1-0512.
22  */
23 
24 /*
25  * This is an open source non-commercial project. Dear PVS-Studio, please check it.
26  * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
27  */
28 
29 #include <config.h>
30 
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <errno.h>
35 
36 #include "sudoers.h"
37 
38 /*
39  * Similar to setenv(3) but operates on a private copy of the environment.
40  * Does not include warnings or debugging to avoid recursive calls.
41  */
42 static int
sudo_setenv_nodebug(const char * var,const char * val,int overwrite)43 sudo_setenv_nodebug(const char *var, const char *val, int overwrite)
44 {
45     char *ep, *estring = NULL;
46     const char *cp;
47     size_t esize;
48     int ret = -1;
49 
50     if (var == NULL || *var == '\0') {
51 	errno = EINVAL;
52 	goto done;
53     }
54 
55     /*
56      * POSIX says a var name with '=' is an error but BSD
57      * just ignores the '=' and anything after it.
58      */
59     for (cp = var; *cp && *cp != '='; cp++)
60 	continue;
61     esize = (size_t)(cp - var) + 2;
62     if (val) {
63 	esize += strlen(val);	/* glibc treats a NULL val as "" */
64     }
65 
66     /* Allocate and fill in estring. */
67     if ((estring = ep = malloc(esize)) == NULL)
68 	goto done;
69     for (cp = var; *cp && *cp != '='; cp++)
70 	*ep++ = *cp;
71     *ep++ = '=';
72     if (val) {
73 	for (cp = val; *cp; cp++)
74 	    *ep++ = *cp;
75     }
76     *ep = '\0';
77 
78     ret = sudo_putenv_nodebug(estring, true, overwrite);
79 done:
80     if (ret == -1)
81 	free(estring);
82     else
83 	sudoers_gc_add(GC_PTR, estring);
84     return ret;
85 }
86 
87 int
sudoers_hook_getenv(const char * name,char ** value,void * closure)88 sudoers_hook_getenv(const char *name, char **value, void *closure)
89 {
90     static bool in_progress = false; /* avoid recursion */
91 
92     if (in_progress || env_get() == NULL)
93 	return SUDO_HOOK_RET_NEXT;
94 
95     in_progress = true;
96 
97     /* Hack to make GNU gettext() find the sudoers locale when needed. */
98     if (*name == 'L' && sudoers_getlocale() == SUDOERS_LOCALE_SUDOERS) {
99 	if (strcmp(name, "LANGUAGE") == 0 || strcmp(name, "LANG") == 0) {
100 	    *value = NULL;
101 	    goto done;
102 	}
103 	if (strcmp(name, "LC_ALL") == 0 || strcmp(name, "LC_MESSAGES") == 0) {
104 	    *value = def_sudoers_locale;
105 	    goto done;
106 	}
107     }
108 
109     *value = sudo_getenv_nodebug(name);
110 done:
111     in_progress = false;
112     return SUDO_HOOK_RET_STOP;
113 }
114 
115 int
sudoers_hook_putenv(char * string,void * closure)116 sudoers_hook_putenv(char *string, void *closure)
117 {
118     static bool in_progress = false; /* avoid recursion */
119 
120     if (in_progress || env_get() == NULL)
121 	return SUDO_HOOK_RET_NEXT;
122 
123     in_progress = true;
124     sudo_putenv_nodebug(string, true, true);
125     in_progress = false;
126     return SUDO_HOOK_RET_STOP;
127 }
128 
129 int
sudoers_hook_setenv(const char * name,const char * value,int overwrite,void * closure)130 sudoers_hook_setenv(const char *name, const char *value, int overwrite, void *closure)
131 {
132     static bool in_progress = false; /* avoid recursion */
133 
134     if (in_progress || env_get() == NULL)
135 	return SUDO_HOOK_RET_NEXT;
136 
137     in_progress = true;
138     sudo_setenv_nodebug(name, value, overwrite);
139     in_progress = false;
140     return SUDO_HOOK_RET_STOP;
141 }
142 
143 int
sudoers_hook_unsetenv(const char * name,void * closure)144 sudoers_hook_unsetenv(const char *name, void *closure)
145 {
146     static bool in_progress = false; /* avoid recursion */
147 
148     if (in_progress || env_get() == NULL)
149 	return SUDO_HOOK_RET_NEXT;
150 
151     in_progress = true;
152     sudo_unsetenv_nodebug(name);
153     in_progress = false;
154     return SUDO_HOOK_RET_STOP;
155 }
156