2 * Copyright (c) 1988 The Regents of the University of California.
5 * This code is derived from software written by Ken Arnold and
6 * published in UNIX Review, Vol. 6, No. 8.
8 * Redistribution and use in source and binary forms are permitted
9 * provided that the above copyright notice and this paragraph are
10 * duplicated in all such forms and that any documentation,
11 * advertising materials, and other materials related to such
12 * distribution and use acknowledge that the software was developed
13 * by the University of California, Berkeley. The name of the
14 * University may not be used to endorse or promote products derived
15 * from this software without specific prior written permission.
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20 * @(#)popen.c 5.7 (Berkeley) 2/14/89
21 * $FreeBSD: src/usr.sbin/cron/cron/popen.c,v 1.7.2.3 2000/12/11 01:03:31 obrien Exp $
22 * $DragonFly: src/usr.sbin/cron/cron/popen.c,v 1.5 2004/12/18 22:48:03 swildner Exp $
25 /* this came out of the ftpd sources; it's been modified to avoid the
26 * globbing stuff since we don't need it. also execvp instead of execv.
30 #include <sys/signal.h>
36 #if defined(LOGIN_CAP)
37 # include <login_cap.h>
42 #define WANT_GLOBBING 0
45 * Special version of popen which avoids call to shell. This insures noone
46 * may create a pipe to a hidden program as a side effect of a list or dir
53 cron_popen(char *program, char *type, entry *e)
60 char *argv[MAX_ARGS + 1];
61 # if defined(LOGIN_CAP)
69 extern char **glob(), **copyblk();
72 if ((*type != 'r' && *type != 'w') || type[1])
76 if ((fds = getdtablesize()) <= 0)
78 if (!(pids = (PID_T *)malloc((u_int)(fds * sizeof(PID_T)))))
80 bzero((char *)pids, fds * sizeof(PID_T));
85 /* break up string into pieces */
86 for (argc = 0, cp = program; argc < MAX_ARGS; cp = NULL)
87 if (!(argv[argc++] = strtok(cp, " \t\n")))
89 argv[MAX_ARGS] = NULL;
94 for (gargc = argc = 1; argv[argc]; argc++) {
95 if (!(pop = glob(argv[argc]))) { /* globbing failed */
100 argv[argc] = (char *)pop; /* save to free later */
101 while (*pop && gargc < 1000)
102 gargv[gargc++] = *pop++;
108 switch(pid = vfork()) {
120 /* get new pgrp, void tty, etc.
125 /* Do not share our parent's stdin */
127 open(_PATH_DEVNULL, O_RDWR);
130 dup2(pdes[1], 2); /* stderr, too! */
139 /* Hack: stdout gets revoked */
141 open(_PATH_DEVNULL, O_RDWR);
143 open(_PATH_DEVNULL, O_RDWR);
146 # if defined(LOGIN_CAP)
148 /* Set user's entire context, but skip the environment
149 * as cron provides a separate interface for this
151 usernm = env_get("LOGNAME", e->envp);
152 if ((pwd = getpwnam(usernm)) == NULL)
153 pwd = getpwuid(e->uid);
156 pwd->pw_gid = e->gid;
157 if (e->class != NULL)
158 lc = login_getclass(e->class);
161 setusercontext(lc, pwd, e->uid,
162 LOGIN_SETALL & ~(LOGIN_SETPATH|LOGIN_SETENV)) == 0)
165 /* fall back to the old method */
168 /* set our directory, uid and gid. Set gid first,
169 * since once we set uid, we've lost root privledges.
173 initgroups(usernm, e->gid);
176 setuid(e->uid); /* we aren't root after this..*/
177 #if defined(LOGIN_CAP)
182 chdir(env_get("HOME", e->envp));
185 execvp(gargv[0], gargv);
187 execvp(argv[0], argv);
191 /* parent; assume fdopen can't fail... */
193 iop = fdopen(pdes[0], type);
196 iop = fdopen(pdes[1], type);
199 pids[fileno(iop)] = pid;
203 for (argc = 1; argv[argc] != NULL; argc++) {
204 /* blkfree((char **)argv[argc]); */
205 free((char *)argv[argc]);
212 cron_pclose(FILE *iop)
220 * pclose returns -1 if stream is not associated with a
221 * `popened' command, or, if already `pclosed'.
223 if (pids == 0 || pids[fdes = fileno(iop)] == 0)
226 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP));
227 while ((pid = wait(&stat_loc)) != pids[fdes] && pid != -1)
231 return (pid == -1 ? -1 : WEXITSTATUS(stat_loc));