2 * Copyright (c) 1996 by
3 * Sean Eric Fagan <sef@kithrup.com>
4 * David Nugent <davidn@blaze.net.au>
7 * Portions copyright (c) 1995,1997
8 * Berkeley Software Design, Inc.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, is permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice immediately at the beginning of the file, without modification,
16 * this list of conditions, and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. This work was done expressly for inclusion into FreeBSD. Other use
21 * is permitted provided this notation is included.
22 * 4. Absolutely no warranty of function or purpose is made by the authors.
23 * 5. Modifications may be freely made to this file providing the above
26 * Low-level routines relating to the user capabilities database
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
39 #include <sys/types.h>
41 #include <sys/resource.h>
42 #include <sys/param.h>
46 #include <login_cap.h>
50 * Manage a single static pointer for handling a local char* buffer,
51 * resizing as necessary to contain the string.
54 * Manage a static array for handling a group of strings, resizing
58 static int lc_object_count = 0;
60 static size_t internal_stringsz = 0;
61 static char * internal_string = NULL;
62 static size_t internal_arraysz = 0;
63 static char ** internal_array = NULL;
70 size_t sz = strlen(str) + 1; /* realloc() only if necessary */
71 if (sz <= internal_stringsz)
72 p = strcpy(internal_string, str);
73 else if ((p = realloc(internal_string, sz)) != NULL) {
74 internal_stringsz = sz;
75 internal_string = strcpy(p, str);
86 if (sz <= internal_arraysz)
88 else if ((p = realloc(internal_array, sz * sizeof(char*))) != NULL) {
89 internal_arraysz = sz;
98 * Turn a simple string <str> separated by any of
99 * the set of <chars> into an array. The last element
100 * of the array will be NULL, as is proper.
101 * Free using freearraystr()
105 arrayize(char *str, const char *chars, int *size)
111 /* count the sub-strings */
112 for (i = 0, ptr = str; *ptr; i++) {
113 int count = strcspn(ptr, chars);
119 /* alloc the array */
120 if ((ptr = allocstr(str)) != NULL) {
121 if ((res = allocarray(++i)) == NULL)
124 /* now split the string */
127 int count = strcspn(ptr, chars);
146 * Frees up all resources relating to a login class
151 login_close(login_cap_t * lc)
158 if (--lc_object_count == 0) {
159 free(internal_string);
160 free(internal_array);
161 internal_array = NULL;
162 internal_arraysz = 0;
163 internal_string = NULL;
164 internal_stringsz = 0;
172 * login_getclassbyname() get the login class by its name.
173 * If the name given is NULL or empty, the default class
174 * LOGIN_DEFCLASS (ie. "default") is fetched. If the
175 * 'dir' argument contains a non-NULL non-empty string,
176 * then the file _FILE_LOGIN_CONF is picked up from that
177 * directory instead of the system login database.
178 * Return a filled-out login_cap_t structure, including
179 * class name, and the capability record buffer.
183 login_getclassbyname(char const *name, const struct passwd *pwd)
187 if ((lc = malloc(sizeof(login_cap_t))) != NULL) {
191 const char *msg = NULL;
193 char userpath[MAXPATHLEN];
195 static char *login_dbarray[] = { NULL, NULL, NULL };
197 me = (name != NULL && strcmp(name, LOGIN_MECLASS) == 0);
198 dir = (!me || pwd == NULL) ? NULL : pwd->pw_dir;
200 * Switch to user mode before checking/reading its ~/.login_conf
201 * - some NFSes have root read access disabled.
203 * XXX: This fails to configure additional groups.
208 (void)setegid(pwd->pw_gid);
209 (void)seteuid(pwd->pw_uid);
212 if (dir && snprintf(userpath, MAXPATHLEN, "%s/%s", dir,
213 _FILE_LOGIN_CONF) < MAXPATHLEN) {
214 login_dbarray[i] = userpath;
215 if (_secure_path(userpath, pwd->pw_uid, pwd->pw_gid) != -1)
216 i++; /* only use 'secure' data */
218 if (_secure_path(_PATH_LOGIN_CONF, 0, 0) != -1)
219 login_dbarray[i++] = _PATH_LOGIN_CONF;
220 login_dbarray[i] = NULL;
222 memset(lc, 0, sizeof(login_cap_t));
223 lc->lc_cap = lc->lc_class = lc->lc_style = NULL;
225 if (name == NULL || *name == '\0')
226 name = LOGIN_DEFCLASS;
228 switch (cgetent(&lc->lc_cap, login_dbarray, (char*)name)) {
229 case -1: /* Failed, entry does not exist */
231 break; /* Don't retry default on 'me' */
234 else if ((r = open(login_dbarray[0], O_RDONLY)) >= 0)
237 * If there's at least one login class database,
238 * and we aren't searching for a default class
239 * then complain about a non-existent class.
241 if (r >= 0 || strcmp(name, LOGIN_DEFCLASS) != 0)
242 syslog(LOG_ERR, "login_getclass: unknown class '%s'", name);
243 /* fall-back to default class */
244 name = LOGIN_DEFCLASS;
245 msg = "%s: no default/fallback class '%s'";
246 if (cgetent(&lc->lc_cap, login_dbarray, (char*)name) != 0 && r >= 0)
248 /* Fallthru - just return system defaults */
249 case 0: /* success! */
250 if ((lc->lc_class = strdup(name)) != NULL) {
258 msg = "%s: strdup: %m";
261 msg = "%s: retrieving class information: %m";
264 msg = "%s: 'tc=' reference loop '%s'";
267 msg = "couldn't resolve 'tc=' reference in '%s'";
270 msg = "%s: unexpected cgetent() error '%s': %m";
278 syslog(LOG_ERR, msg, "login_getclass", name);
289 * Get the login class for the system (only) login class database.
290 * Return a filled-out login_cap_t structure, including
291 * class name, and the capability record buffer.
295 login_getclass(const char *cls)
297 return login_getclassbyname(cls, NULL);
303 * Get the login class for a given password entry from
304 * the system (only) login class database.
305 * If the password entry's class field is not set, or
306 * the class specified does not exist, then use the
307 * default of LOGIN_DEFCLASS (ie. "default").
308 * Return a filled-out login_cap_t structure, including
309 * class name, and the capability record buffer.
313 login_getpwclass(const struct passwd *pwd)
315 const char *cls = NULL;
319 if (cls == NULL || *cls == '\0')
320 cls = (pwd->pw_uid == 0) ? LOGIN_DEFROOTCLASS : LOGIN_DEFCLASS;
322 return login_getclassbyname(cls, pwd);
327 * login_getuserclass()
328 * Get the login class for a given password entry, allowing user
329 * overrides via ~/.login_conf.
333 login_getuserclass(const struct passwd *pwd)
335 return login_getclassbyname(LOGIN_MECLASS, pwd);
342 * Given a login_cap entry, and a capability name, return the
343 * value defined for that capability, a defualt if not found, or
344 * an error string on error.
348 login_getcapstr(login_cap_t *lc, const char *cap, char *def, char *error)
353 if (lc == NULL || cap == NULL || lc->lc_cap == NULL || *cap == '\0')
356 if ((ret = cgetstr(lc->lc_cap, (char *)cap, &res)) == -1)
358 return (ret >= 0) ? res : error;
364 * Given a login_cap entry, and a capability name, return the
365 * value defined for that capability split into an array of
370 login_getcaplist(login_cap_t *lc, const char *cap, const char *chars)
376 if ((lstring = login_getcapstr(lc, cap, NULL, NULL)) != NULL)
377 return arrayize(lstring, chars, NULL);
384 * From the login_cap_t <lc>, get the capability <cap> which is
385 * formatted as either a space or comma delimited list of paths
386 * and append them all into a string and separate by semicolons.
387 * If there is an error of any kind, return <error>.
391 login_getpath(login_cap_t *lc, const char *cap, char * error)
395 if ((str = login_getcapstr(lc, (char*)cap, NULL, NULL)) == NULL)
401 int count = strcspn(ptr, ", \t");
412 isinfinite(const char *s)
414 static const char *infs[] = {
422 const char **i = &infs[0];
425 if (strcasecmp(s, *i) == 0)
434 rmultiply(u_quad_t n1, u_quad_t n2)
441 /* Handle simple cases */
442 if (n1 == 0 || n2 == 0)
450 * sizeof() returns number of bytes needed for storage.
451 * This may be different from the actual number of useful bits.
454 bpw = sizeof(u_quad_t) * 8;
455 while (((u_quad_t)1 << (bpw-1)) == 0)
460 * First check the magnitude of each number. If the sum of the
461 * magnatude is way to high, reject the number. (If this test
462 * is not done then the first multiply below may overflow.)
464 for (b1 = bpw; (((u_quad_t)1 << (b1-1)) & n1) == 0; --b1)
466 for (b2 = bpw; (((u_quad_t)1 << (b2-1)) & n2) == 0; --b2)
468 if (b1 + b2 - 2 > bpw) {
474 * Decompose the multiplication to be:
479 * (h1 + l1) * (h2 + l2)
480 * (h1 * h2) + (h1 * l2) + (l1 * h2) + (l1 * l2)
482 * Since h1 && h2 do not have the low bit set, we can then say:
484 * (h1>>1 * h2>>1 * 4) + ...
486 * So if (h1>>1 * h2>>1) > (1<<(bpw - 2)) then the result will
489 * Finally, if MAX - ((h1 * l2) + (l1 * h2) + (l1 * l2)) < (h1*h2)
490 * then adding in residual amout will cause an overflow.
493 m = (n1 >> 1) * (n2 >> 1);
494 if (m >= ((u_quad_t)1 << (bpw-2))) {
501 + (n2 & 1) * (n1 & ~(u_quad_t)1)
502 + (n1 & 1) * (n2 & ~(u_quad_t)1);
504 if ((u_quad_t)(m + r) < m) {
516 * From the login_cap_t <lc>, get the capability <cap>, which is
517 * formatted as a time (e.g., "<cap>=10h3m2s"). If <cap> is not
518 * present in <lc>, return <def>; if there is an error of some kind,
523 login_getcaptime(login_cap_t *lc, const char *cap, rlim_t def, rlim_t error)
525 char *res, *ep, *oval;
530 if (lc == NULL || lc->lc_cap == NULL)
534 * Look for <cap> in lc_cap.
535 * If it's not there (-1), return <def>.
536 * If there's an error, return <error>.
539 if ((r = cgetstr(lc->lc_cap, (char *)cap, &res)) == -1)
546 /* "inf" and "infinity" are special cases */
548 return RLIM_INFINITY;
551 * Now go through the string, turning something like 1h2m3s into
552 * an integral value. Whee.
559 rlim_t tim = strtoq(res, &ep, 0);
562 if (ep == NULL || ep == res || errno != 0) {
564 syslog(LOG_WARNING, "login_getcaptime: class '%s' bad value %s=%s",
565 lc->lc_class, cap, oval);
569 /* Look for suffixes */
573 break; /* end of string */
574 case 's': case 'S': /* seconds */
576 case 'm': case 'M': /* minutes */
579 case 'h': case 'H': /* hours */
582 case 'd': case 'D': /* days */
583 mult = 60L * 60L * 24L;
585 case 'w': case 'W': /* weeks */
586 mult = 60L * 60L * 24L * 7L;
588 case 'y': case 'Y': /* 365-day years */
589 mult = 60L * 60L * 24L * 365L;
595 tot += rmultiply(tim, mult);
606 * From the login_cap_t <lc>, extract the numerical value <cap>.
607 * If it is not present, return <def> for a default, and return
608 * <error> if there is an error.
609 * Like login_getcaptime(), only it only converts to a number, not
610 * to a time; "infinity" and "inf" are 'special.'
614 login_getcapnum(login_cap_t *lc, const char *cap, rlim_t def, rlim_t error)
620 if (lc == NULL || lc->lc_cap == NULL)
624 * For BSDI compatibility, try for the tag=<val> first
626 if ((r = cgetstr(lc->lc_cap, (char *)cap, &res)) == -1) {
628 /* string capability not present, so try for tag#<val> as numeric */
629 if ((r = cgetnum(lc->lc_cap, (char *)cap, &lval)) == -1)
630 return def; /* Not there, so return default */
641 return RLIM_INFINITY;
644 val = strtoq(res, &ep, 0);
645 if (ep == NULL || ep == res || errno != 0) {
646 syslog(LOG_WARNING, "login_getcapnum: class '%s' bad value %s=%s",
647 lc->lc_class, cap, res);
659 * From the login_cap_t <lc>, extract the capability <cap>, which is
660 * formatted as a size (e.g., "<cap>=10M"); it can also be "infinity".
661 * If not present, return <def>, or <error> if there is an error of
666 login_getcapsize(login_cap_t *lc, const char *cap, rlim_t def, rlim_t error)
668 char *ep, *res, *oval;
672 if (lc == NULL || lc->lc_cap == NULL)
675 if ((r = cgetstr(lc->lc_cap, (char *)cap, &res)) == -1)
683 return RLIM_INFINITY;
689 rlim_t siz = strtoq(res, &ep, 0);
692 if (ep == NULL || ep == res || errno != 0) {
694 syslog(LOG_WARNING, "login_getcapsize: class '%s' bad value %s=%s",
695 lc->lc_class, cap, oval);
700 case 0: /* end of string */
703 case 'b': case 'B': /* 512-byte blocks */
706 case 'k': case 'K': /* 1024-byte Kilobytes */
709 case 'm': case 'M': /* 1024-k kbytes */
712 case 'g': case 'G': /* 1Gbyte */
713 mult = 1024 * 1024 * 1024;
715 case 't': case 'T': /* 1TBte */
716 mult = 1024LL * 1024LL * 1024LL * 1024LL;
722 tot += rmultiply(siz, mult);
733 * From the login_cap_t <lc>, check for the existance of the capability
734 * of <cap>. Return <def> if <lc>->lc_cap is NULL, otherwise return
735 * the whether or not <cap> exists there.
739 login_getcapbool(login_cap_t *lc, const char *cap, int def)
741 if (lc == NULL || lc->lc_cap == NULL)
743 return (cgetcap(lc->lc_cap, (char *)cap, ':') != NULL);
749 * Given a login_cap entry <lc>, and optionally a type of auth <auth>,
750 * and optionally a style <style>, find the style that best suits these
752 * 1. If <auth> is non-null, look for an "auth-<auth>=" string
753 * in the capability; if not present, default to "auth=".
754 * 2. If there is no auth list found from (1), default to
755 * "passwd" as an authorization list.
756 * 3. If <style> is non-null, look for <style> in the list of
757 * authorization methods found from (2); if <style> is NULL, default
758 * to LOGIN_DEFSTYLE ("passwd").
759 * 4. If the chosen style is found in the chosen list of authorization
760 * methods, return that; otherwise, return NULL.
762 * login_getstyle(lc, NULL, "ftp");
763 * login_getstyle(lc, "login", NULL);
764 * login_getstyle(lc, "skey", "network");
768 login_getstyle(login_cap_t *lc, char *style, const char *auth)
771 char **authtypes = NULL;
775 static char *defauthtypes[] = { LOGIN_DEFSTYLE, NULL };
777 if (auth != NULL && *auth != '\0') {
778 if (snprintf(realauth, sizeof realauth, "auth-%s", auth) < sizeof realauth)
779 authtypes = login_getcaplist(lc, realauth, NULL);
782 if (authtypes == NULL)
783 authtypes = login_getcaplist(lc, "auth", NULL);
785 if (authtypes == NULL)
786 authtypes = defauthtypes;
789 * We have at least one authtype now; auths is a comma-separated
790 * (or space-separated) list of authentication types. We have to
791 * convert from this to an array of char*'s; authtypes then gets this.
794 if (style != NULL && *style != '\0') {
795 while (authtypes[i] != NULL && strcmp(style, authtypes[i]) != 0)
800 if (authtypes[i] != NULL && (auths = strdup(authtypes[i])) != NULL)
801 lc->lc_style = auths;
803 if (lc->lc_style != NULL)
804 lc->lc_style = strdup(lc->lc_style);