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 #endif /* not lint */ 42 43 #include <sys/cdefs.h> 44 __FBSDID("$FreeBSD$"); 45 46 #include <sys/types.h> 47 #include <sys/wait.h> 48 #include <netinet/in.h> 49 50 #include <errno.h> 51 #include <glob.h> 52 #include <signal.h> 53 #include <stdio.h> 54 #include <stdlib.h> 55 #include <string.h> 56 #include <unistd.h> 57 58 #include "extern.h" 59 #include "pathnames.h" 60 #include <syslog.h> 61 #include <time.h> 62 63 #define MAXUSRARGS 100 64 #define MAXGLOBARGS 1000 65 66 /* 67 * Special version of popen which avoids call to shell. This ensures noone 68 * may create a pipe to a hidden program as a side effect of a list or dir 69 * command. 70 */ 71 static int *pids; 72 static int fds; 73 74 FILE * 75 ftpd_popen(char *program, char *type) 76 { 77 char *cp; 78 FILE *iop; 79 int argc, gargc, pdes[2], pid; 80 char **pop, *argv[MAXUSRARGS], *gargv[MAXGLOBARGS]; 81 82 if (((*type != 'r') && (*type != 'w')) || type[1]) 83 return (NULL); 84 85 if (!pids) { 86 if ((fds = getdtablesize()) <= 0) 87 return (NULL); 88 if ((pids = malloc(fds * sizeof(int))) == NULL) 89 return (NULL); 90 memset(pids, 0, fds * sizeof(int)); 91 } 92 if (pipe(pdes) < 0) 93 return (NULL); 94 95 /* break up string into pieces */ 96 for (argc = 0, cp = program; argc < MAXUSRARGS; cp = NULL) { 97 if (!(argv[argc++] = strtok(cp, " \t\n"))) 98 break; 99 } 100 argv[argc - 1] = NULL; 101 102 /* glob each piece */ 103 gargv[0] = argv[0]; 104 for (gargc = argc = 1; argv[argc] && gargc < (MAXGLOBARGS-1); argc++) { 105 glob_t gl; 106 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE; 107 108 memset(&gl, 0, sizeof(gl)); 109 gl.gl_matchc = MAXGLOBARGS; 110 flags |= GLOB_LIMIT; 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 fflush(NULL); 123 pid = (strcmp(gargv[0], _PATH_LS) == 0) ? fork() : vfork(); 124 switch(pid) { 125 case -1: /* error */ 126 (void)close(pdes[0]); 127 (void)close(pdes[1]); 128 goto pfree; 129 /* NOTREACHED */ 130 case 0: /* child */ 131 if (*type == 'r') { 132 if (pdes[1] != STDOUT_FILENO) { 133 dup2(pdes[1], STDOUT_FILENO); 134 (void)close(pdes[1]); 135 } 136 dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */ 137 (void)close(pdes[0]); 138 } else { 139 if (pdes[0] != STDIN_FILENO) { 140 dup2(pdes[0], STDIN_FILENO); 141 (void)close(pdes[0]); 142 } 143 (void)close(pdes[1]); 144 } 145 if (strcmp(gargv[0], _PATH_LS) == 0) { 146 /* Reset getopt for ls_main() */ 147 optreset = optind = optopt = 1; 148 /* Close syslogging to remove pwd.db missing msgs */ 149 closelog(); 150 /* Trigger to sense new /etc/localtime after chroot */ 151 if (getenv("TZ") == NULL) { 152 setenv("TZ", "", 0); 153 tzset(); 154 unsetenv("TZ"); 155 tzset(); 156 } 157 exit(ls_main(gargc, gargv)); 158 } 159 execv(gargv[0], gargv); 160 _exit(1); 161 } 162 /* parent; assume fdopen can't fail... */ 163 if (*type == 'r') { 164 iop = fdopen(pdes[0], type); 165 (void)close(pdes[1]); 166 } else { 167 iop = fdopen(pdes[1], type); 168 (void)close(pdes[0]); 169 } 170 pids[fileno(iop)] = pid; 171 172 pfree: for (argc = 1; gargv[argc] != NULL; argc++) 173 free(gargv[argc]); 174 175 return (iop); 176 } 177 178 int 179 ftpd_pclose(FILE *iop) 180 { 181 int fdes, omask, status; 182 pid_t pid; 183 184 /* 185 * pclose returns -1 if stream is not associated with a 186 * `popened' command, or, if already `pclosed'. 187 */ 188 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 189 return (-1); 190 (void)fclose(iop); 191 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); 192 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 193 continue; 194 (void)sigsetmask(omask); 195 pids[fdes] = 0; 196 if (pid < 0) 197 return (pid); 198 if (WIFEXITED(status)) 199 return (WEXITSTATUS(status)); 200 return (1); 201 } 202