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. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)popen.c 8.3 (Berkeley) 4/6/94 33 * $FreeBSD: src/libexec/ftpd/popen.c,v 1.26 2004/11/18 13:46:29 yar Exp $ 34 */ 35 36 #include <sys/types.h> 37 #include <sys/wait.h> 38 #include <netinet/in.h> 39 40 #include <errno.h> 41 #include <glob.h> 42 #include <signal.h> 43 #include <stdio.h> 44 #include <stdlib.h> 45 #include <string.h> 46 #include <unistd.h> 47 48 #include "extern.h" 49 #include "pathnames.h" 50 #include <syslog.h> 51 #include <time.h> 52 53 #define MAXUSRARGS 100 54 #define MAXGLOBARGS 1000 55 56 /* 57 * Special version of popen which avoids call to shell. This ensures noone 58 * may create a pipe to a hidden program as a side effect of a list or dir 59 * command. 60 */ 61 static int *pids; 62 static int fds; 63 64 FILE * 65 ftpd_popen(char *program, char *type) 66 { 67 char *cp; 68 FILE *iop; 69 int argc, gargc, pdes[2], pid; 70 char **pop, *argv[MAXUSRARGS], *gargv[MAXGLOBARGS]; 71 72 if (((*type != 'r') && (*type != 'w')) || type[1]) 73 return (NULL); 74 75 if (!pids) { 76 if ((fds = getdtablesize()) <= 0) 77 return (NULL); 78 if ((pids = malloc(fds * sizeof(int))) == NULL) 79 return (NULL); 80 memset(pids, 0, fds * sizeof(int)); 81 } 82 if (pipe(pdes) < 0) 83 return (NULL); 84 85 /* break up string into pieces */ 86 for (argc = 0, cp = program; argc < MAXUSRARGS; cp = NULL) { 87 if (!(argv[argc++] = strtok(cp, " \t\n"))) 88 break; 89 } 90 argv[argc - 1] = NULL; 91 92 /* glob each piece */ 93 gargv[0] = argv[0]; 94 for (gargc = argc = 1; argv[argc] && gargc < (MAXGLOBARGS-1); argc++) { 95 glob_t gl; 96 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE; 97 98 memset(&gl, 0, sizeof(gl)); 99 gl.gl_matchc = MAXGLOBARGS; 100 /*flags |= GLOB_LIMIT;*/ 101 if (glob(argv[argc], flags, NULL, &gl)) 102 gargv[gargc++] = strdup(argv[argc]); 103 else 104 for (pop = gl.gl_pathv; *pop && gargc < (MAXGLOBARGS-1); 105 pop++) 106 gargv[gargc++] = strdup(*pop); 107 globfree(&gl); 108 } 109 gargv[gargc] = NULL; 110 111 iop = NULL; 112 fflush(NULL); 113 pid = (strcmp(gargv[0], _PATH_LS) == 0) ? fork() : vfork(); 114 switch(pid) { 115 case -1: /* error */ 116 close(pdes[0]); 117 close(pdes[1]); 118 goto pfree; 119 /* NOTREACHED */ 120 case 0: /* child */ 121 if (*type == 'r') { 122 if (pdes[1] != STDOUT_FILENO) { 123 dup2(pdes[1], STDOUT_FILENO); 124 close(pdes[1]); 125 } 126 dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */ 127 close(pdes[0]); 128 } else { 129 if (pdes[0] != STDIN_FILENO) { 130 dup2(pdes[0], STDIN_FILENO); 131 close(pdes[0]); 132 } 133 close(pdes[1]); 134 } 135 if (strcmp(gargv[0], _PATH_LS) == 0) { 136 /* Reset getopt for ls_main() */ 137 optreset = optind = optopt = 1; 138 /* Close syslogging to remove pwd.db missing msgs */ 139 closelog(); 140 /* Trigger to sense new /etc/localtime after chroot */ 141 if (getenv("TZ") == NULL) { 142 if (setenv("TZ", "", 0) == -1) 143 syslog(LOG_ERR, "setenv: cannot set TZ: %m"); 144 tzset(); 145 unsetenv("TZ"); 146 tzset(); 147 } 148 exit(ls_main(gargc, gargv)); 149 } 150 execv(gargv[0], gargv); 151 _exit(1); 152 } 153 /* parent; assume fdopen can't fail... */ 154 if (*type == 'r') { 155 iop = fdopen(pdes[0], type); 156 close(pdes[1]); 157 } else { 158 iop = fdopen(pdes[1], type); 159 close(pdes[0]); 160 } 161 pids[fileno(iop)] = pid; 162 163 pfree: for (argc = 1; gargv[argc] != NULL; argc++) 164 free(gargv[argc]); 165 166 return (iop); 167 } 168 169 int 170 ftpd_pclose(FILE *iop) 171 { 172 int fdes, omask, status; 173 pid_t pid; 174 175 /* 176 * pclose returns -1 if stream is not associated with a 177 * `popened' command, or, if already `pclosed'. 178 */ 179 if (pids == NULL || pids[fdes = fileno(iop)] == 0) 180 return (-1); 181 fclose(iop); 182 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); 183 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 184 continue; 185 sigsetmask(omask); 186 pids[fdes] = 0; 187 if (pid < 0) 188 return (pid); 189 if (WIFEXITED(status)) 190 return (WEXITSTATUS(status)); 191 return (1); 192 } 193