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 * @(#)popen.c 8.3 (Berkeley) 4/6/94 37 * $FreeBSD: src/libexec/ftpd/popen.c,v 1.26 2004/11/18 13:46:29 yar Exp $ 38 * $DragonFly: src/libexec/ftpd/popen.c,v 1.3 2006/01/12 13:43:10 corecode Exp $ 39 */ 40 41 #include <sys/types.h> 42 #include <sys/wait.h> 43 #include <netinet/in.h> 44 45 #include <errno.h> 46 #include <glob.h> 47 #include <signal.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <string.h> 51 #include <unistd.h> 52 53 #include "extern.h" 54 #include "pathnames.h" 55 #include <syslog.h> 56 #include <time.h> 57 58 #define MAXUSRARGS 100 59 #define MAXGLOBARGS 1000 60 61 /* 62 * Special version of popen which avoids call to shell. This ensures noone 63 * may create a pipe to a hidden program as a side effect of a list or dir 64 * command. 65 */ 66 static int *pids; 67 static int fds; 68 69 FILE * 70 ftpd_popen(char *program, char *type) 71 { 72 char *cp; 73 FILE *iop; 74 int argc, gargc, pdes[2], pid; 75 char **pop, *argv[MAXUSRARGS], *gargv[MAXGLOBARGS]; 76 77 if (((*type != 'r') && (*type != 'w')) || type[1]) 78 return (NULL); 79 80 if (!pids) { 81 if ((fds = getdtablesize()) <= 0) 82 return (NULL); 83 if ((pids = malloc(fds * sizeof(int))) == NULL) 84 return (NULL); 85 memset(pids, 0, fds * sizeof(int)); 86 } 87 if (pipe(pdes) < 0) 88 return (NULL); 89 90 /* break up string into pieces */ 91 for (argc = 0, cp = program; argc < MAXUSRARGS; cp = NULL) { 92 if (!(argv[argc++] = strtok(cp, " \t\n"))) 93 break; 94 } 95 argv[argc - 1] = NULL; 96 97 /* glob each piece */ 98 gargv[0] = argv[0]; 99 for (gargc = argc = 1; argv[argc] && gargc < (MAXGLOBARGS-1); argc++) { 100 glob_t gl; 101 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE; 102 103 memset(&gl, 0, sizeof(gl)); 104 gl.gl_matchc = MAXGLOBARGS; 105 flags |= GLOB_LIMIT; 106 if (glob(argv[argc], flags, NULL, &gl)) 107 gargv[gargc++] = strdup(argv[argc]); 108 else 109 for (pop = gl.gl_pathv; *pop && gargc < (MAXGLOBARGS-1); 110 pop++) 111 gargv[gargc++] = strdup(*pop); 112 globfree(&gl); 113 } 114 gargv[gargc] = NULL; 115 116 iop = NULL; 117 fflush(NULL); 118 pid = (strcmp(gargv[0], _PATH_LS) == 0) ? fork() : vfork(); 119 switch(pid) { 120 case -1: /* error */ 121 close(pdes[0]); 122 close(pdes[1]); 123 goto pfree; 124 /* NOTREACHED */ 125 case 0: /* child */ 126 if (*type == 'r') { 127 if (pdes[1] != STDOUT_FILENO) { 128 dup2(pdes[1], STDOUT_FILENO); 129 close(pdes[1]); 130 } 131 dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */ 132 close(pdes[0]); 133 } else { 134 if (pdes[0] != STDIN_FILENO) { 135 dup2(pdes[0], STDIN_FILENO); 136 close(pdes[0]); 137 } 138 close(pdes[1]); 139 } 140 if (strcmp(gargv[0], _PATH_LS) == 0) { 141 /* Reset getopt for ls_main() */ 142 optreset = optind = optopt = 1; 143 /* Close syslogging to remove pwd.db missing msgs */ 144 closelog(); 145 /* Trigger to sense new /etc/localtime after chroot */ 146 if (getenv("TZ") == NULL) { 147 if (setenv("TZ", "", 0) == -1) 148 syslog(LOG_ERR, "setenv: cannot set TZ: %m"); 149 tzset(); 150 unsetenv("TZ"); 151 tzset(); 152 } 153 exit(ls_main(gargc, gargv)); 154 } 155 execv(gargv[0], gargv); 156 _exit(1); 157 } 158 /* parent; assume fdopen can't fail... */ 159 if (*type == 'r') { 160 iop = fdopen(pdes[0], type); 161 close(pdes[1]); 162 } else { 163 iop = fdopen(pdes[1], type); 164 close(pdes[0]); 165 } 166 pids[fileno(iop)] = pid; 167 168 pfree: for (argc = 1; gargv[argc] != NULL; argc++) 169 free(gargv[argc]); 170 171 return (iop); 172 } 173 174 int 175 ftpd_pclose(FILE *iop) 176 { 177 int fdes, omask, status; 178 pid_t pid; 179 180 /* 181 * pclose returns -1 if stream is not associated with a 182 * `popened' command, or, if already `pclosed'. 183 */ 184 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 185 return (-1); 186 fclose(iop); 187 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); 188 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 189 continue; 190 sigsetmask(omask); 191 pids[fdes] = 0; 192 if (pid < 0) 193 return (pid); 194 if (WIFEXITED(status)) 195 return (WEXITSTATUS(status)); 196 return (1); 197 } 198