1 /* 2 * Copyright (c) 1988, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software written by Ken Arnold and 6 * published in UNIX Review, Vol. 6, No. 8. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)popen.c 8.3 (Berkeley) 4/6/94"; 40 #endif 41 static const char rcsid[] = 42 "$Id: popen.c,v 1.14 1998/05/15 16:51:06 ache Exp $"; 43 #endif /* not lint */ 44 45 #include <sys/types.h> 46 #include <sys/wait.h> 47 48 #include <errno.h> 49 #include <glob.h> 50 #include <signal.h> 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <unistd.h> 55 56 #include "extern.h" 57 #ifdef INTERNAL_LS 58 #include "pathnames.h" 59 #include <syslog.h> 60 #include <time.h> 61 #include <varargs.h> 62 #endif 63 64 #define MAXUSRARGS 100 65 #define MAXGLOBARGS 1000 66 67 /* 68 * Special version of popen which avoids call to shell. This ensures noone 69 * may create a pipe to a hidden program as a side effect of a list or dir 70 * command. 71 */ 72 static int *pids; 73 static int fds; 74 75 FILE * 76 ftpd_popen(program, type) 77 char *program, *type; 78 { 79 char *cp; 80 FILE *iop; 81 int argc, gargc, pdes[2], pid; 82 char **pop, *argv[MAXUSRARGS], *gargv[MAXGLOBARGS]; 83 84 if (((*type != 'r') && (*type != 'w')) || type[1]) 85 return (NULL); 86 87 if (!pids) { 88 if ((fds = getdtablesize()) <= 0) 89 return (NULL); 90 if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL) 91 return (NULL); 92 memset(pids, 0, fds * sizeof(int)); 93 } 94 if (pipe(pdes) < 0) 95 return (NULL); 96 97 /* break up string into pieces */ 98 for (argc = 0, cp = program; argc < MAXUSRARGS; cp = NULL) { 99 if (!(argv[argc++] = strtok(cp, " \t\n"))) 100 break; 101 } 102 argv[argc - 1] = NULL; 103 104 /* glob each piece */ 105 gargv[0] = argv[0]; 106 for (gargc = argc = 1; argv[argc] && gargc < (MAXGLOBARGS-1); argc++) { 107 glob_t gl; 108 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE; 109 110 memset(&gl, 0, sizeof(gl)); 111 if (glob(argv[argc], flags, NULL, &gl)) 112 gargv[gargc++] = strdup(argv[argc]); 113 else 114 for (pop = gl.gl_pathv; *pop && gargc < (MAXGLOBARGS-1); 115 pop++) 116 gargv[gargc++] = strdup(*pop); 117 globfree(&gl); 118 } 119 gargv[gargc] = NULL; 120 121 iop = NULL; 122 #ifdef INTERNAL_LS 123 fflush(NULL); 124 pid = (strcmp(gargv[0], _PATH_LS) == 0) ? fork() : vfork(); 125 #else 126 pid = vfork(); 127 #endif 128 switch(pid) { 129 case -1: /* error */ 130 (void)close(pdes[0]); 131 (void)close(pdes[1]); 132 goto pfree; 133 /* NOTREACHED */ 134 case 0: /* child */ 135 if (*type == 'r') { 136 if (pdes[1] != STDOUT_FILENO) { 137 dup2(pdes[1], STDOUT_FILENO); 138 (void)close(pdes[1]); 139 } 140 dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */ 141 (void)close(pdes[0]); 142 } else { 143 if (pdes[0] != STDIN_FILENO) { 144 dup2(pdes[0], STDIN_FILENO); 145 (void)close(pdes[0]); 146 } 147 (void)close(pdes[1]); 148 } 149 #ifdef INTERNAL_LS 150 if (strcmp(gargv[0], _PATH_LS) == 0) { 151 extern int optreset; 152 /* Reset getopt for ls_main() */ 153 optreset = optind = optopt = 1; 154 /* Close syslogging to remove pwd.db missing msgs */ 155 closelog(); 156 /* Trigger to sense new /etc/localtime after chroot */ 157 if (getenv("TZ") == NULL) { 158 setenv("TZ", "", 0); 159 tzset(); 160 unsetenv("TZ"); 161 tzset(); 162 } 163 exit(ls_main(gargc, gargv)); 164 } 165 #endif 166 execv(gargv[0], gargv); 167 _exit(1); 168 } 169 /* parent; assume fdopen can't fail... */ 170 if (*type == 'r') { 171 iop = fdopen(pdes[0], type); 172 (void)close(pdes[1]); 173 } else { 174 iop = fdopen(pdes[1], type); 175 (void)close(pdes[0]); 176 } 177 pids[fileno(iop)] = pid; 178 179 pfree: for (argc = 1; gargv[argc] != NULL; argc++) 180 free(gargv[argc]); 181 182 return (iop); 183 } 184 185 int 186 ftpd_pclose(iop) 187 FILE *iop; 188 { 189 int fdes, omask, status; 190 pid_t pid; 191 192 /* 193 * pclose returns -1 if stream is not associated with a 194 * `popened' command, or, if already `pclosed'. 195 */ 196 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 197 return (-1); 198 (void)fclose(iop); 199 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); 200 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 201 continue; 202 (void)sigsetmask(omask); 203 pids[fdes] = 0; 204 if (pid < 0) 205 return (pid); 206 if (WIFEXITED(status)) 207 return (WEXITSTATUS(status)); 208 return (1); 209 } 210