1: /*
2: * Copyright (c) 2000-2005, 2007-2013
3: * Todd C. Miller <Todd.Miller@courtesan.com>
4: *
5: * Permission to use, copy, modify, and distribute this software for any
6: * purpose with or without fee is hereby granted, provided that the above
7: * copyright notice and this permission notice appear in all copies.
8: *
9: * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10: * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11: * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12: * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13: * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14: * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15: * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16: *
17: * Sponsored in part by the Defense Advanced Research Projects
18: * Agency (DARPA) and Air Force Research Laboratory, Air Force
19: * Materiel Command, USAF, under agreement number F39502-99-1-0512.
20: */
21:
22: #include <config.h>
23:
24: #include <sys/types.h>
25: #include <sys/stat.h>
26: #include <stdio.h>
27: #ifdef STDC_HEADERS
28: # include <stdlib.h>
29: # include <stddef.h>
30: #else
31: # ifdef HAVE_STDLIB_H
32: # include <stdlib.h>
33: # endif
34: #endif /* STDC_HEADERS */
35: #ifdef HAVE_STRING_H
36: # include <string.h>
37: #endif /* HAVE_STRING_H */
38: #ifdef HAVE_STRINGS_H
39: # include <strings.h>
40: #endif /* HAVE_STRINGS_H */
41: #ifdef HAVE_UNISTD_H
42: # include <unistd.h>
43: #endif /* HAVE_UNISTD_H */
44: #ifdef HAVE_INTTYPES_H
45: # include <inttypes.h>
46: #endif
47: #ifdef HAVE_LOGIN_CAP_H
48: # include <login_cap.h>
49: # ifndef LOGIN_SETENV
50: # define LOGIN_SETENV 0
51: # endif
52: #endif /* HAVE_LOGIN_CAP_H */
53: #include <ctype.h>
54: #include <errno.h>
55: #include <limits.h>
56: #include <pwd.h>
57:
58: #include "sudoers.h"
59:
60: /*
61: * If there is no SIZE_MAX or SIZE_T_MAX we have to assume that size_t
62: * could be signed (as it is on SunOS 4.x). This just means that
63: * emalloc2() and erealloc3() cannot allocate huge amounts on such a
64: * platform but that is OK since sudo doesn't need to do so anyway.
65: */
66: #ifndef SIZE_MAX
67: # ifdef SIZE_T_MAX
68: # define SIZE_MAX SIZE_T_MAX
69: # else
70: # define SIZE_MAX INT_MAX
71: # endif /* SIZE_T_MAX */
72: #endif /* SIZE_MAX */
73:
74: /*
75: * Flags used in rebuild_env()
76: */
77: #undef DID_TERM
78: #define DID_TERM 0x0001
79: #undef DID_PATH
80: #define DID_PATH 0x0002
81: #undef DID_HOME
82: #define DID_HOME 0x0004
83: #undef DID_SHELL
84: #define DID_SHELL 0x0008
85: #undef DID_LOGNAME
86: #define DID_LOGNAME 0x0010
87: #undef DID_USER
88: #define DID_USER 0x0020
89: #undef DID_USERNAME
90: #define DID_USERNAME 0x0040
91: #undef DID_MAIL
92: #define DID_MAIL 0x0080
93: #undef DID_MAX
94: #define DID_MAX 0x00ff
95:
96: #undef KEPT_TERM
97: #define KEPT_TERM 0x0100
98: #undef KEPT_PATH
99: #define KEPT_PATH 0x0200
100: #undef KEPT_HOME
101: #define KEPT_HOME 0x0400
102: #undef KEPT_SHELL
103: #define KEPT_SHELL 0x0800
104: #undef KEPT_LOGNAME
105: #define KEPT_LOGNAME 0x1000
106: #undef KEPT_USER
107: #define KEPT_USER 0x2000
108: #undef KEPT_USERNAME
109: #define KEPT_USERNAME 0x4000
110: #undef KEPT_MAIL
111: #define KEPT_MAIL 0x8000
112: #undef KEPT_MAX
113: #define KEPT_MAX 0xff00
114:
115: struct environment {
116: char * const *old_envp; /* pointer the environment we passed back */
117: char **envp; /* pointer to the new environment */
118: size_t env_size; /* size of new_environ in char **'s */
119: size_t env_len; /* number of slots used, not counting NULL */
120: };
121:
122: /*
123: * Copy of the sudo-managed environment.
124: */
125: static struct environment env;
126:
127: /*
128: * Default table of "bad" variables to remove from the environment.
129: * XXX - how to omit TERMCAP if it starts with '/'?
130: */
131: static const char *initial_badenv_table[] = {
132: "IFS",
133: "CDPATH",
134: "LOCALDOMAIN",
135: "RES_OPTIONS",
136: "HOSTALIASES",
137: "NLSPATH",
138: "PATH_LOCALE",
139: "LD_*",
140: "_RLD*",
141: #ifdef __hpux
142: "SHLIB_PATH",
143: #endif /* __hpux */
144: #ifdef _AIX
145: "LDR_*",
146: "LIBPATH",
147: "AUTHSTATE",
148: #endif
149: #ifdef __APPLE__
150: "DYLD_*",
151: #endif
152: #ifdef HAVE_KERB5
153: "KRB5_CONFIG*",
154: "KRB5_KTNAME",
155: #endif /* HAVE_KERB5 */
156: #ifdef HAVE_SECURID
157: "VAR_ACE",
158: "USR_ACE",
159: "DLC_ACE",
160: #endif /* HAVE_SECURID */
161: "TERMINFO", /* terminfo, exclusive path to terminfo files */
162: "TERMINFO_DIRS", /* terminfo, path(s) to terminfo files */
163: "TERMPATH", /* termcap, path(s) to termcap files */
164: "TERMCAP", /* XXX - only if it starts with '/' */
165: "ENV", /* ksh, file to source before script runs */
166: "BASH_ENV", /* bash, file to source before script runs */
167: "PS4", /* bash, prefix for lines in xtrace mode */
168: "GLOBIGNORE", /* bash, globbing patterns to ignore */
169: "SHELLOPTS", /* bash, extra command line options */
170: "JAVA_TOOL_OPTIONS", /* java, extra command line options */
171: "PERLIO_DEBUG ", /* perl, debugging output file */
172: "PERLLIB", /* perl, search path for modules/includes */
173: "PERL5LIB", /* perl 5, search path for modules/includes */
174: "PERL5OPT", /* perl 5, extra command line options */
175: "PERL5DB", /* perl 5, command used to load debugger */
176: "FPATH", /* ksh, search path for functions */
177: "NULLCMD", /* zsh, command for null file redirection */
178: "READNULLCMD", /* zsh, command for null file redirection */
179: "ZDOTDIR", /* zsh, search path for dot files */
180: "TMPPREFIX", /* zsh, prefix for temporary files */
181: "PYTHONHOME", /* python, module search path */
182: "PYTHONPATH", /* python, search path */
183: "PYTHONINSPECT", /* python, allow inspection */
184: "PYTHONUSERBASE", /* python, per user site-packages directory */
185: "RUBYLIB", /* ruby, library load path */
186: "RUBYOPT", /* ruby, extra command line options */
187: NULL
188: };
189:
190: /*
191: * Default table of variables to check for '%' and '/' characters.
192: */
193: static const char *initial_checkenv_table[] = {
194: "COLORTERM",
195: "LANG",
196: "LANGUAGE",
197: "LC_*",
198: "LINGUAS",
199: "TERM",
200: NULL
201: };
202:
203: /*
204: * Default table of variables to preserve in the environment.
205: */
206: static const char *initial_keepenv_table[] = {
207: "COLORS",
208: "DISPLAY",
209: "HOSTNAME",
210: "KRB5CCNAME",
211: "LS_COLORS",
212: "PATH",
213: "PS1",
214: "PS2",
215: "TZ",
216: "XAUTHORITY",
217: "XAUTHORIZATION",
218: NULL
219: };
220:
221: /*
222: * Initialize env based on envp.
223: */
224: void
225: env_init(char * const envp[])
226: {
227: char * const *ep;
228: size_t len;
229: debug_decl(env_init, SUDO_DEBUG_ENV)
230:
231: if (envp == NULL) {
232: /* Reset to initial state but keep a pointer to what we allocated. */
233: envp = env.envp;
234: memset(&env, 0, sizeof(env));
235: env.old_envp = envp;
236: } else {
237: /* Make private copy of envp. */
238: for (ep = envp; *ep != NULL; ep++)
239: continue;
240: len = (size_t)(ep - envp);
241:
242: env.env_len = len;
243: env.env_size = len + 1 + 128;
244: env.envp = emalloc2(env.env_size, sizeof(char *));
245: #ifdef ENV_DEBUG
246: memset(env.envp, 0, env.env_size * sizeof(char *));
247: #endif
248: memcpy(env.envp, envp, len * sizeof(char *));
249: env.envp[len] = NULL;
250:
251: /* Free the old envp we allocated, if any. */
252: if (env.old_envp != NULL)
253: efree((void *)env.old_envp);
254: }
255:
256: debug_return;
257: }
258:
259: /*
260: * Getter for private copy of the environment.
261: */
262: char **
263: env_get(void)
264: {
265: return env.envp;
266: }
267:
268: /*
269: * Similar to putenv(3) but operates on sudo's private copy of the
270: * environment (not environ) and it always overwrites. The dupcheck param
271: * determines whether we need to verify that the variable is not already set.
272: * Will only overwrite an existing variable if overwrite is set.
273: * Does not include warnings or debugging to avoid recursive calls.
274: */
275: static int
276: sudo_putenv_nodebug(char *str, bool dupcheck, bool overwrite)
277: {
278: char **ep;
279: size_t len;
280: bool found = false;
281:
282: /* Make sure there is room for the new entry plus a NULL. */
283: if (env.env_size > 2 && env.env_len > env.env_size - 2) {
284: char **nenvp;
285: size_t nsize;
286:
287: if (env.env_size > SIZE_MAX - 128) {
288: fatalx_nodebug(U_("internal error, %s overflow"),
289: "sudo_putenv_nodebug()");
290: }
291: nsize = env.env_size + 128;
292: if (nsize > SIZE_MAX / sizeof(char *)) {
293: fatalx_nodebug(U_("internal error, %s overflow"),
294: "sudo_putenv_nodebug()");
295: }
296: nenvp = realloc(env.envp, nsize * sizeof(char *));
297: if (nenvp == NULL) {
298: errno = ENOMEM;
299: return -1;
300: }
301: env.envp = nenvp;
302: env.env_size = nsize;
303: #ifdef ENV_DEBUG
304: memset(env.envp + env.env_len, 0,
305: (env.env_size - env.env_len) * sizeof(char *));
306: #endif
307: }
308:
309: #ifdef ENV_DEBUG
310: if (env.envp[env.env_len] != NULL) {
311: errno = EINVAL;
312: return -1;
313: }
314: #endif
315:
316: if (dupcheck) {
317: len = (strchr(str, '=') - str) + 1;
318: for (ep = env.envp; *ep != NULL; ep++) {
319: if (strncmp(str, *ep, len) == 0) {
320: if (overwrite)
321: *ep = str;
322: found = true;
323: break;
324: }
325: }
326: /* Prune out extra instances of the variable we just overwrote. */
327: if (found && overwrite) {
328: while (*++ep != NULL) {
329: if (strncmp(str, *ep, len) == 0) {
330: char **cur = ep;
331: while ((*cur = *(cur + 1)) != NULL)
332: cur++;
333: ep--;
334: }
335: }
336: env.env_len = ep - env.envp;
337: }
338: }
339:
340: if (!found) {
341: ep = env.envp + env.env_len;
342: env.env_len++;
343: *ep++ = str;
344: *ep = NULL;
345: }
346: return 0;
347: }
348:
349: /*
350: * Similar to putenv(3) but operates on sudo's private copy of the
351: * environment (not environ) and it always overwrites. The dupcheck param
352: * determines whether we need to verify that the variable is not already set.
353: * Will only overwrite an existing variable if overwrite is set.
354: */
355: static int
356: sudo_putenv(char *str, bool dupcheck, bool overwrite)
357: {
358: int rval;
359: debug_decl(sudo_putenv, SUDO_DEBUG_ENV)
360:
361: sudo_debug_printf(SUDO_DEBUG_INFO, "sudo_putenv: %s", str);
362:
363: rval = sudo_putenv_nodebug(str, dupcheck, overwrite);
364: if (rval == -1) {
365: #ifdef ENV_DEBUG
366: if (env.envp[env.env_len] != NULL)
367: fatalx(U_("sudo_putenv: corrupted envp, length mismatch"));
368: #endif
369: fatal(NULL);
370: }
371: debug_return_int(rval);
372: }
373:
374: /*
375: * Similar to setenv(3) but operates on a private copy of the environment.
376: * The dupcheck param determines whether we need to verify that the variable
377: * is not already set.
378: */
379: static int
380: sudo_setenv2(const char *var, const char *val, bool dupcheck, bool overwrite)
381: {
382: char *estring;
383: size_t esize;
384: int rval;
385: debug_decl(sudo_setenv2, SUDO_DEBUG_ENV)
386:
387: esize = strlen(var) + 1 + strlen(val) + 1;
388: estring = emalloc(esize);
389:
390: /* Build environment string and insert it. */
391: if (strlcpy(estring, var, esize) >= esize ||
392: strlcat(estring, "=", esize) >= esize ||
393: strlcat(estring, val, esize) >= esize) {
394:
395: fatalx(U_("internal error, %s overflow"), "sudo_setenv2()");
396: }
397: rval = sudo_putenv(estring, dupcheck, overwrite);
398: if (rval == -1)
399: efree(estring);
400: debug_return_int(rval);
401: }
402:
403: /*
404: * Similar to setenv(3) but operates on a private copy of the environment.
405: */
406: int
407: sudo_setenv(const char *var, const char *val, int overwrite)
408: {
409: return sudo_setenv2(var, val, true, (bool)overwrite);
410: }
411:
412: /*
413: * Similar to setenv(3) but operates on a private copy of the environment.
414: * Does not include warnings or debugging to avoid recursive calls.
415: */
416: static int
417: sudo_setenv_nodebug(const char *var, const char *val, int overwrite)
418: {
419: char *ep, *estring = NULL;
420: const char *cp;
421: size_t esize;
422: int rval = -1;
423:
424: if (var == NULL || *var == '\0') {
425: errno = EINVAL;
426: goto done;
427: }
428:
429: /*
430: * POSIX says a var name with '=' is an error but BSD
431: * just ignores the '=' and anything after it.
432: */
433: for (cp = var; *cp && *cp != '='; cp++)
434: ;
435: esize = (size_t)(cp - var) + 2;
436: if (val) {
437: esize += strlen(val); /* glibc treats a NULL val as "" */
438: }
439:
440: /* Allocate and fill in estring. */
441: if ((estring = ep = malloc(esize)) == NULL) {
442: errno = ENOMEM;
443: goto done;
444: }
445: for (cp = var; *cp && *cp != '='; cp++)
446: *ep++ = *cp;
447: *ep++ = '=';
448: if (val) {
449: for (cp = val; *cp; cp++)
450: *ep++ = *cp;
451: }
452: *ep = '\0';
453:
454: rval = sudo_putenv_nodebug(estring, true, overwrite);
455: done:
456: if (rval == -1)
457: free(estring);
458: return rval;
459: }
460:
461: /*
462: * Similar to unsetenv(3) but operates on a private copy of the environment.
463: * Does not include warnings or debugging to avoid recursive calls.
464: */
465: static int
466: sudo_unsetenv_nodebug(const char *var)
467: {
468: char **ep = env.envp;
469: size_t len;
470:
471: if (ep == NULL || var == NULL || *var == '\0' || strchr(var, '=') != NULL) {
472: errno = EINVAL;
473: return -1;
474: }
475:
476: len = strlen(var);
477: while (*ep != NULL) {
478: if (strncmp(var, *ep, len) == 0 && (*ep)[len] == '=') {
479: /* Found it; shift remainder + NULL over by one. */
480: char **cur = ep;
481: while ((*cur = *(cur + 1)) != NULL)
482: cur++;
483: /* Keep going, could be multiple instances of the var. */
484: } else {
485: ep++;
486: }
487: }
488: return 0;
489: }
490:
491: /*
492: * Similar to unsetenv(3) but operates on a private copy of the environment.
493: */
494: int
495: sudo_unsetenv(const char *name)
496: {
497: int rval;
498: debug_decl(sudo_unsetenv, SUDO_DEBUG_ENV)
499:
500: sudo_debug_printf(SUDO_DEBUG_INFO, "sudo_unsetenv: %s", name);
501:
502: rval = sudo_unsetenv_nodebug(name);
503:
504: debug_return_int(rval);
505: }
506:
507: /*
508: * Similar to getenv(3) but operates on a private copy of the environment.
509: * Does not include warnings or debugging to avoid recursive calls.
510: */
511: static char *
512: sudo_getenv_nodebug(const char *name)
513: {
514: char **ep, *val = NULL;
515: size_t namelen = 0;
516:
517: if (env.env_len != 0) {
518: /* For BSD compatibility, treat '=' in name like end of string. */
519: while (name[namelen] != '\0' && name[namelen] != '=')
520: namelen++;
521: for (ep = env.envp; *ep != NULL; ep++) {
522: if (strncmp(*ep, name, namelen) == 0 && (*ep)[namelen] == '=') {
523: val = *ep + namelen + 1;
524: break;
525: }
526: }
527: }
528: return val;
529: }
530:
531: /*
532: * Similar to getenv(3) but operates on a private copy of the environment.
533: */
534: char *
535: sudo_getenv(const char *name)
536: {
537: char *val;
538: debug_decl(sudo_getenv, SUDO_DEBUG_ENV)
539:
540: sudo_debug_printf(SUDO_DEBUG_INFO, "sudo_getenv: %s", name);
541:
542: val = sudo_getenv_nodebug(name);
543:
544: debug_return_str(val);
545: }
546:
547: /*
548: * Check the env_delete blacklist.
549: * Returns true if the variable was found, else false.
550: */
551: static bool
552: matches_env_delete(const char *var)
553: {
554: struct list_member *cur;
555: size_t len;
556: bool iswild;
557: bool match = false;
558: debug_decl(matches_env_delete, SUDO_DEBUG_ENV)
559:
560: /* Skip anything listed in env_delete. */
561: SLIST_FOREACH(cur, &def_env_delete, entries) {
562: len = strlen(cur->value);
563: /* Deal with '*' wildcard */
564: if (cur->value[len - 1] == '*') {
565: len--;
566: iswild = true;
567: } else
568: iswild = false;
569: if (strncmp(cur->value, var, len) == 0 &&
570: (iswild || var[len] == '=')) {
571: match = true;
572: break;
573: }
574: }
575: debug_return_bool(match);
576: }
577:
578: /*
579: * Apply the env_check list.
580: * Returns true if the variable is allowed, false if denied
581: * or -1 if no match.
582: */
583: static int
584: matches_env_check(const char *var)
585: {
586: struct list_member *cur;
587: size_t len;
588: bool iswild;
589: int keepit = -1;
590: debug_decl(matches_env_check, SUDO_DEBUG_ENV)
591:
592: SLIST_FOREACH(cur, &def_env_check, entries) {
593: len = strlen(cur->value);
594: /* Deal with '*' wildcard */
595: if (cur->value[len - 1] == '*') {
596: len--;
597: iswild = true;
598: } else
599: iswild = false;
600: if (strncmp(cur->value, var, len) == 0 &&
601: (iswild || var[len] == '=')) {
602: keepit = !strpbrk(var, "/%");
603: break;
604: }
605: }
606: debug_return_bool(keepit);
607: }
608:
609: /*
610: * Check the env_keep list.
611: * Returns true if the variable is allowed else false.
612: */
613: static bool
614: matches_env_keep(const char *var)
615: {
616: struct list_member *cur;
617: size_t len;
618: bool iswild, keepit = false;
619: debug_decl(matches_env_keep, SUDO_DEBUG_ENV)
620:
621: /* Preserve SHELL variable for "sudo -s". */
622: if (ISSET(sudo_mode, MODE_SHELL) && strncmp(var, "SHELL=", 6) == 0) {
623: keepit = true;
624: goto done;
625: }
626:
627: SLIST_FOREACH(cur, &def_env_keep, entries) {
628: len = strlen(cur->value);
629: /* Deal with '*' wildcard */
630: if (cur->value[len - 1] == '*') {
631: len--;
632: iswild = true;
633: } else
634: iswild = false;
635: if (strncmp(cur->value, var, len) == 0 &&
636: (iswild || var[len] == '=')) {
637: keepit = true;
638: break;
639: }
640: }
641: done:
642: debug_return_bool(keepit);
643: }
644:
645: /*
646: * Look up var in the env_delete and env_check.
647: * Returns true if we should delete the variable, else false.
648: */
649: static bool
650: env_should_delete(const char *var)
651: {
652: int delete_it;
653: debug_decl(env_should_delete, SUDO_DEBUG_ENV);
654:
655: delete_it = matches_env_delete(var);
656: if (!delete_it)
657: delete_it = matches_env_check(var) == false;
658:
659: sudo_debug_printf(SUDO_DEBUG_INFO, "delete %s: %s",
660: var, delete_it ? "YES" : "NO");
661: debug_return_bool(delete_it);
662: }
663:
664: /*
665: * Lookup var in the env_check and env_keep lists.
666: * Returns true if the variable is allowed else false.
667: */
668: static bool
669: env_should_keep(const char *var)
670: {
671: int keepit;
672: debug_decl(env_should_keep, SUDO_DEBUG_ENV)
673:
674: keepit = matches_env_check(var);
675: if (keepit == -1)
676: keepit = matches_env_keep(var);
677:
678: sudo_debug_printf(SUDO_DEBUG_INFO, "keep %s: %s",
679: var, keepit ? "YES" : "NO");
680: debug_return_bool(keepit == true);
681: }
682:
683: /*
684: * Merge another environment with our private copy.
685: * Only overwrite an existing variable if it is not
686: * being preserved from the user's environment.
687: */
688: void
689: env_merge(char * const envp[])
690: {
691: char * const *ep;
692: debug_decl(env_merge, SUDO_DEBUG_ENV)
693:
694: for (ep = envp; *ep != NULL; ep++)
695: sudo_putenv(*ep, true, !env_should_keep(*ep));
696:
697: debug_return;
698: }
699:
700: static void
701: env_update_didvar(const char *ep, unsigned int *didvar)
702: {
703: switch (*ep) {
704: case 'H':
705: if (strncmp(ep, "HOME=", 5) == 0)
706: SET(*didvar, DID_HOME);
707: break;
708: case 'L':
709: if (strncmp(ep, "LOGNAME=", 8) == 0)
710: SET(*didvar, DID_LOGNAME);
711: break;
712: case 'M':
713: if (strncmp(ep, "MAIL=", 5) == 0)
714: SET(*didvar, DID_MAIL);
715: break;
716: case 'P':
717: if (strncmp(ep, "PATH=", 5) == 0)
718: SET(*didvar, DID_PATH);
719: break;
720: case 'S':
721: if (strncmp(ep, "SHELL=", 6) == 0)
722: SET(*didvar, DID_SHELL);
723: break;
724: case 'T':
725: if (strncmp(ep, "TERM=", 5) == 0)
726: SET(*didvar, DID_TERM);
727: break;
728: case 'U':
729: if (strncmp(ep, "USER=", 5) == 0)
730: SET(*didvar, DID_USER);
731: if (strncmp(ep, "USERNAME=", 5) == 0)
732: SET(*didvar, DID_USERNAME);
733: break;
734: }
735: }
736:
737: /*
738: * Build a new environment and ether clear potentially dangerous
739: * variables from the old one or start with a clean slate.
740: * Also adds sudo-specific variables (SUDO_*).
741: */
742: void
743: rebuild_env(void)
744: {
745: char **old_envp, **ep, *cp, *ps1;
746: char idbuf[MAX_UID_T_LEN + 1];
747: unsigned int didvar;
748: bool reset_home = false;
749:
750: /*
751: * Either clean out the environment or reset to a safe default.
752: */
753: ps1 = NULL;
754: didvar = 0;
755: env.env_len = 0;
756: env.env_size = 128;
757: old_envp = env.envp;
758: env.envp = emalloc2(env.env_size, sizeof(char *));
759: #ifdef ENV_DEBUG
760: memset(env.envp, 0, env.env_size * sizeof(char *));
761: #else
762: env.envp[0] = NULL;
763: #endif
764:
765: /* Reset HOME based on target user if configured to. */
766: if (ISSET(sudo_mode, MODE_RUN)) {
767: if (def_always_set_home ||
768: ISSET(sudo_mode, MODE_RESET_HOME | MODE_LOGIN_SHELL) ||
769: (ISSET(sudo_mode, MODE_SHELL) && def_set_home))
770: reset_home = true;
771: }
772:
773: if (def_env_reset || ISSET(sudo_mode, MODE_LOGIN_SHELL)) {
774: /*
775: * If starting with a fresh environment, initialize it based on
776: * /etc/environment or login.conf. For "sudo -i" we want those
777: * variables to override the invoking user's environment, so we
778: * defer reading them until later.
779: */
780: if (!ISSET(sudo_mode, MODE_LOGIN_SHELL)) {
781: #ifdef HAVE_LOGIN_CAP_H
782: /* Insert login class environment variables. */
783: if (login_class) {
784: login_cap_t *lc = login_getclass(login_class);
785: if (lc != NULL) {
786: setusercontext(lc, runas_pw, runas_pw->pw_uid,
787: LOGIN_SETPATH|LOGIN_SETENV);
788: login_close(lc);
789: }
790: }
791: #endif /* HAVE_LOGIN_CAP_H */
792: #if defined(_AIX) || (defined(__linux__) && !defined(HAVE_PAM))
793: /* Insert system-wide environment variables. */
794: read_env_file(_PATH_ENVIRONMENT, true);
795: #endif
796: for (ep = env.envp; *ep; ep++)
797: env_update_didvar(*ep, &didvar);
798: }
799:
800: /* Pull in vars we want to keep from the old environment. */
801: for (ep = old_envp; *ep; ep++) {
802: bool keepit;
803:
804: /* Skip variables with values beginning with () (bash functions) */
805: if ((cp = strchr(*ep, '=')) != NULL) {
806: if (strncmp(cp, "=() ", 3) == 0)
807: continue;
808: }
809:
810: /*
811: * Look up the variable in the env_check and env_keep lists.
812: */
813: keepit = env_should_keep(*ep);
814:
815: /*
816: * Do SUDO_PS1 -> PS1 conversion.
817: * This must happen *after* env_should_keep() is called.
818: */
819: if (strncmp(*ep, "SUDO_PS1=", 8) == 0)
820: ps1 = *ep + 5;
821:
822: if (keepit) {
823: /* Preserve variable. */
824: sudo_putenv(*ep, false, false);
825: env_update_didvar(*ep, &didvar);
826: }
827: }
828: didvar |= didvar << 8; /* convert DID_* to KEPT_* */
829:
830: /*
831: * Add in defaults. In -i mode these come from the runas user,
832: * otherwise they may be from the user's environment (depends
833: * on sudoers options).
834: */
835: if (ISSET(sudo_mode, MODE_LOGIN_SHELL)) {
836: sudo_setenv2("SHELL", runas_pw->pw_shell,
837: ISSET(didvar, DID_SHELL), true);
838: sudo_setenv2("LOGNAME", runas_pw->pw_name,
839: ISSET(didvar, DID_LOGNAME), true);
840: sudo_setenv2("USER", runas_pw->pw_name,
841: ISSET(didvar, DID_USER), true);
842: sudo_setenv2("USERNAME", runas_pw->pw_name,
843: ISSET(didvar, DID_USERNAME), true);
844: } else {
845: if (!ISSET(didvar, DID_SHELL))
846: sudo_setenv2("SHELL", sudo_user.pw->pw_shell, false, true);
847: /* We will set LOGNAME later in the !def_set_logname case. */
848: if (!def_set_logname) {
849: if (!ISSET(didvar, DID_LOGNAME))
850: sudo_setenv2("LOGNAME", user_name, false, true);
851: if (!ISSET(didvar, DID_USER))
852: sudo_setenv2("USER", user_name, false, true);
853: if (!ISSET(didvar, DID_USERNAME))
854: sudo_setenv2("USERNAME", user_name, false, true);
855: }
856: }
857:
858: /* If we didn't keep HOME, reset it based on target user. */
859: if (!ISSET(didvar, KEPT_HOME))
860: reset_home = true;
861:
862: /*
863: * Set MAIL to target user in -i mode or if MAIL is not preserved
864: * from user's environment.
865: */
866: if (ISSET(sudo_mode, MODE_LOGIN_SHELL) || !ISSET(didvar, KEPT_MAIL)) {
867: cp = _PATH_MAILDIR;
868: if (cp[sizeof(_PATH_MAILDIR) - 2] == '/')
869: easprintf(&cp, "MAIL=%s%s", _PATH_MAILDIR, runas_pw->pw_name);
870: else
871: easprintf(&cp, "MAIL=%s/%s", _PATH_MAILDIR, runas_pw->pw_name);
872: sudo_putenv(cp, ISSET(didvar, DID_MAIL), true);
873: }
874: } else {
875: /*
876: * Copy environ entries as long as they don't match env_delete or
877: * env_check.
878: */
879: for (ep = old_envp; *ep; ep++) {
880: /* Skip variables with values beginning with () (bash functions) */
881: if ((cp = strchr(*ep, '=')) != NULL) {
882: if (strncmp(cp, "=() ", 3) == 0)
883: continue;
884: }
885:
886: /* Add variable unless it matches a black list. */
887: if (!env_should_delete(*ep)) {
888: if (strncmp(*ep, "SUDO_PS1=", 9) == 0)
889: ps1 = *ep + 5;
890: else if (strncmp(*ep, "PATH=", 5) == 0)
891: SET(didvar, DID_PATH);
892: else if (strncmp(*ep, "TERM=", 5) == 0)
893: SET(didvar, DID_TERM);
894: sudo_putenv(*ep, false, false);
895: }
896: }
897: }
898: /* Replace the PATH envariable with a secure one? */
899: if (def_secure_path && !user_is_exempt()) {
900: sudo_setenv2("PATH", def_secure_path, true, true);
901: SET(didvar, DID_PATH);
902: }
903:
904: /*
905: * Set $USER, $LOGNAME and $USERNAME to target if "set_logname" is not
906: * disabled. We skip this if we are running a login shell (because
907: * they have already been set) or sudoedit (because we want the editor
908: * to find the invoking user's startup files).
909: */
910: if (def_set_logname && !ISSET(sudo_mode, MODE_LOGIN_SHELL|MODE_EDIT)) {
911: if (!ISSET(didvar, KEPT_LOGNAME))
912: sudo_setenv2("LOGNAME", runas_pw->pw_name, true, true);
913: if (!ISSET(didvar, KEPT_USER))
914: sudo_setenv2("USER", runas_pw->pw_name, true, true);
915: if (!ISSET(didvar, KEPT_USERNAME))
916: sudo_setenv2("USERNAME", runas_pw->pw_name, true, true);
917: }
918:
919: /* Set $HOME to target user if not preserving user's value. */
920: if (reset_home)
921: sudo_setenv2("HOME", runas_pw->pw_dir, true, true);
922:
923: /* Provide default values for $TERM and $PATH if they are not set. */
924: if (!ISSET(didvar, DID_TERM))
925: sudo_putenv("TERM=unknown", false, false);
926: if (!ISSET(didvar, DID_PATH))
927: sudo_setenv2("PATH", _PATH_STDPATH, false, true);
928:
929: /* Set PS1 if SUDO_PS1 is set. */
930: if (ps1 != NULL)
931: sudo_putenv(ps1, true, true);
932:
933: /* Add the SUDO_COMMAND envariable (cmnd + args). */
934: if (user_args) {
935: easprintf(&cp, "%s %s", user_cmnd, user_args);
936: sudo_setenv2("SUDO_COMMAND", cp, true, true);
937: efree(cp);
938: } else {
939: sudo_setenv2("SUDO_COMMAND", user_cmnd, true, true);
940: }
941:
942: /* Add the SUDO_USER, SUDO_UID, SUDO_GID environment variables. */
943: sudo_setenv2("SUDO_USER", user_name, true, true);
944: snprintf(idbuf, sizeof(idbuf), "%u", (unsigned int) user_uid);
945: sudo_setenv2("SUDO_UID", idbuf, true, true);
946: snprintf(idbuf, sizeof(idbuf), "%u", (unsigned int) user_gid);
947: sudo_setenv2("SUDO_GID", idbuf, true, true);
948:
949: /* Free old environment. */
950: efree(old_envp);
951: }
952:
953: void
954: insert_env_vars(char * const envp[])
955: {
956: char * const *ep;
957:
958: if (envp == NULL)
959: return;
960:
961: /* Add user-specified environment variables. */
962: for (ep = envp; *ep != NULL; ep++)
963: sudo_putenv(*ep, true, true);
964: }
965:
966: /*
967: * Validate the list of environment variables passed in on the command
968: * line against env_delete, env_check, and env_keep.
969: * Calls log_fatal() if any specified variables are not allowed.
970: */
971: void
972: validate_env_vars(char * const env_vars[])
973: {
974: char * const *ep;
975: char *eq, *bad = NULL;
976: size_t len, blen = 0, bsize = 0;
977: bool okvar;
978:
979: if (env_vars == NULL)
980: return;
981:
982: /* Add user-specified environment variables. */
983: for (ep = env_vars; *ep != NULL; ep++) {
984: if (def_secure_path && !user_is_exempt() &&
985: strncmp(*ep, "PATH=", 5) == 0) {
986: okvar = false;
987: } else if (def_env_reset) {
988: okvar = env_should_keep(*ep);
989: } else {
990: okvar = !env_should_delete(*ep);
991: }
992: if (okvar == false) {
993: /* Not allowed, add to error string, allocating as needed. */
994: if ((eq = strchr(*ep, '=')) != NULL)
995: *eq = '\0';
996: len = strlen(*ep) + 2;
997: if (blen + len >= bsize) {
998: do {
999: bsize += 1024;
1000: } while (blen + len >= bsize);
1001: bad = erealloc(bad, bsize);
1002: bad[blen] = '\0';
1003: }
1004: strlcat(bad, *ep, bsize);
1005: strlcat(bad, ", ", bsize);
1006: blen += len;
1007: if (eq != NULL)
1008: *eq = '=';
1009: }
1010: }
1011: if (bad != NULL) {
1012: bad[blen - 2] = '\0'; /* remove trailing ", " */
1013: log_fatal(NO_MAIL,
1014: N_("sorry, you are not allowed to set the following environment variables: %s"), bad);
1015: /* NOTREACHED */
1016: efree(bad);
1017: }
1018: }
1019:
1020: /*
1021: * Read in /etc/environment ala AIX and Linux.
1022: * Lines may be in either of three formats:
1023: * NAME=VALUE
1024: * NAME="VALUE"
1025: * NAME='VALUE'
1026: * with an optional "export" prefix so the shell can source the file.
1027: * Invalid lines, blank lines, or lines consisting solely of a comment
1028: * character are skipped.
1029: */
1030: void
1031: read_env_file(const char *path, int overwrite)
1032: {
1033: FILE *fp;
1034: char *cp, *var, *val, *line = NULL;
1035: size_t var_len, val_len, linesize = 0;
1036:
1037: if ((fp = fopen(path, "r")) == NULL)
1038: return;
1039:
1040: while (sudo_parseln(&line, &linesize, NULL, fp) != -1) {
1041: /* Skip blank or comment lines */
1042: if (*(var = line) == '\0')
1043: continue;
1044:
1045: /* Skip optional "export " */
1046: if (strncmp(var, "export", 6) == 0 && isspace((unsigned char) var[6])) {
1047: var += 7;
1048: while (isspace((unsigned char) *var)) {
1049: var++;
1050: }
1051: }
1052:
1053: /* Must be of the form name=["']value['"] */
1054: for (val = var; *val != '\0' && *val != '='; val++)
1055: ;
1056: if (var == val || *val != '=')
1057: continue;
1058: var_len = (size_t)(val - var);
1059: val_len = strlen(++val);
1060:
1061: /* Strip leading and trailing single/double quotes */
1062: if ((val[0] == '\'' || val[0] == '\"') && val[0] == val[val_len - 1]) {
1063: val[val_len - 1] = '\0';
1064: val++;
1065: val_len -= 2;
1066: }
1067:
1068: cp = emalloc(var_len + 1 + val_len + 1);
1069: memcpy(cp, var, var_len + 1); /* includes '=' */
1070: memcpy(cp + var_len + 1, val, val_len + 1); /* includes NUL */
1071:
1072: sudo_putenv(cp, true, overwrite);
1073: }
1074: free(line);
1075: fclose(fp);
1076: }
1077:
1078: void
1079: init_envtables(void)
1080: {
1081: struct list_member *cur;
1082: const char **p;
1083:
1084: /* Fill in the "env_delete" list. */
1085: for (p = initial_badenv_table; *p; p++) {
1086: cur = ecalloc(1, sizeof(struct list_member));
1087: cur->value = estrdup(*p);
1088: SLIST_INSERT_HEAD(&def_env_delete, cur, entries);
1089: }
1090:
1091: /* Fill in the "env_check" list. */
1092: for (p = initial_checkenv_table; *p; p++) {
1093: cur = ecalloc(1, sizeof(struct list_member));
1094: cur->value = estrdup(*p);
1095: SLIST_INSERT_HEAD(&def_env_check, cur, entries);
1096: }
1097:
1098: /* Fill in the "env_keep" list. */
1099: for (p = initial_keepenv_table; *p; p++) {
1100: cur = ecalloc(1, sizeof(struct list_member));
1101: cur->value = estrdup(*p);
1102: SLIST_INSERT_HEAD(&def_env_keep, cur, entries);
1103: }
1104: }
1105:
1106: int
1107: sudoers_hook_getenv(const char *name, char **value, void *closure)
1108: {
1109: static bool in_progress = false; /* avoid recursion */
1110:
1111: if (in_progress || env.envp == NULL)
1112: return SUDO_HOOK_RET_NEXT;
1113:
1114: in_progress = true;
1115:
1116: /* Hack to make GNU gettext() find the sudoers locale when needed. */
1117: if (*name == 'L' && sudoers_getlocale() == SUDOERS_LOCALE_SUDOERS) {
1118: if (strcmp(name, "LANGUAGE") == 0 || strcmp(name, "LANG") == 0) {
1119: *value = NULL;
1120: goto done;
1121: }
1122: if (strcmp(name, "LC_ALL") == 0 || strcmp(name, "LC_MESSAGES") == 0) {
1123: *value = def_sudoers_locale;
1124: goto done;
1125: }
1126: }
1127:
1128: *value = sudo_getenv_nodebug(name);
1129: done:
1130: in_progress = false;
1131: return SUDO_HOOK_RET_STOP;
1132: }
1133:
1134: int
1135: sudoers_hook_putenv(char *string, void *closure)
1136: {
1137: static bool in_progress = false; /* avoid recursion */
1138:
1139: if (in_progress || env.envp == NULL)
1140: return SUDO_HOOK_RET_NEXT;
1141:
1142: in_progress = true;
1143: sudo_putenv_nodebug(string, true, true);
1144: in_progress = false;
1145: return SUDO_HOOK_RET_STOP;
1146: }
1147:
1148: int
1149: sudoers_hook_setenv(const char *name, const char *value, int overwrite, void *closure)
1150: {
1151: static bool in_progress = false; /* avoid recursion */
1152:
1153: if (in_progress || env.envp == NULL)
1154: return SUDO_HOOK_RET_NEXT;
1155:
1156: in_progress = true;
1157: sudo_setenv_nodebug(name, value, overwrite);
1158: in_progress = false;
1159: return SUDO_HOOK_RET_STOP;
1160: }
1161:
1162: int
1163: sudoers_hook_unsetenv(const char *name, void *closure)
1164: {
1165: static bool in_progress = false; /* avoid recursion */
1166:
1167: if (in_progress || env.envp == NULL)
1168: return SUDO_HOOK_RET_NEXT;
1169:
1170: in_progress = true;
1171: sudo_unsetenv_nodebug(name);
1172: in_progress = false;
1173: return SUDO_HOOK_RET_STOP;
1174: }
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