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 "$FreeBSD$"; 43 #endif /* not lint */ 44 45 #include <sys/types.h> 46 #include <sys/wait.h> 47 #include <netinet/in.h> 48 49 #include <errno.h> 50 #include <glob.h> 51 #include <signal.h> 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <unistd.h> 56 57 #include "extern.h" 58 #include "pathnames.h" 59 #include <syslog.h> 60 #include <time.h> 61 #include <varargs.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(program, type) 76 char *program, *type; 77 { 78 char *cp; 79 FILE *iop; 80 int argc, gargc, pdes[2], pid; 81 char **pop, *argv[MAXUSRARGS], *gargv[MAXGLOBARGS]; 82 83 if (((*type != 'r') && (*type != 'w')) || type[1]) 84 return (NULL); 85 86 if (!pids) { 87 if ((fds = getdtablesize()) <= 0) 88 return (NULL); 89 if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL) 90 return (NULL); 91 memset(pids, 0, fds * sizeof(int)); 92 } 93 if (pipe(pdes) < 0) 94 return (NULL); 95 96 /* break up string into pieces */ 97 for (argc = 0, cp = program; argc < MAXUSRARGS; cp = NULL) { 98 if (!(argv[argc++] = strtok(cp, " \t\n"))) 99 break; 100 } 101 argv[argc - 1] = NULL; 102 103 /* glob each piece */ 104 gargv[0] = argv[0]; 105 for (gargc = argc = 1; argv[argc] && gargc < (MAXGLOBARGS-1); argc++) { 106 glob_t gl; 107 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE; 108 109 memset(&gl, 0, sizeof(gl)); 110 gl.gl_matchc = MAXGLOBARGS; 111 flags |= GLOB_LIMIT; 112 if (glob(argv[argc], flags, NULL, &gl)) 113 gargv[gargc++] = strdup(argv[argc]); 114 else 115 for (pop = gl.gl_pathv; *pop && gargc < (MAXGLOBARGS-1); 116 pop++) 117 gargv[gargc++] = strdup(*pop); 118 globfree(&gl); 119 } 120 gargv[gargc] = NULL; 121 122 iop = NULL; 123 fflush(NULL); 124 pid = (strcmp(gargv[0], _PATH_LS) == 0) ? fork() : vfork(); 125 switch(pid) { 126 case -1: /* error */ 127 (void)close(pdes[0]); 128 (void)close(pdes[1]); 129 goto pfree; 130 /* NOTREACHED */ 131 case 0: /* child */ 132 if (*type == 'r') { 133 if (pdes[1] != STDOUT_FILENO) { 134 dup2(pdes[1], STDOUT_FILENO); 135 (void)close(pdes[1]); 136 } 137 dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */ 138 (void)close(pdes[0]); 139 } else { 140 if (pdes[0] != STDIN_FILENO) { 141 dup2(pdes[0], STDIN_FILENO); 142 (void)close(pdes[0]); 143 } 144 (void)close(pdes[1]); 145 } 146 if (strcmp(gargv[0], _PATH_LS) == 0) { 147 /* Reset getopt for ls_main() */ 148 optreset = optind = optopt = 1; 149 /* Close syslogging to remove pwd.db missing msgs */ 150 closelog(); 151 /* Trigger to sense new /etc/localtime after chroot */ 152 if (getenv("TZ") == NULL) { 153 setenv("TZ", "", 0); 154 tzset(); 155 unsetenv("TZ"); 156 tzset(); 157 } 158 exit(ls_main(gargc, gargv)); 159 } 160 execv(gargv[0], gargv); 161 _exit(1); 162 } 163 /* parent; assume fdopen can't fail... */ 164 if (*type == 'r') { 165 iop = fdopen(pdes[0], type); 166 (void)close(pdes[1]); 167 } else { 168 iop = fdopen(pdes[1], type); 169 (void)close(pdes[0]); 170 } 171 pids[fileno(iop)] = pid; 172 173 pfree: for (argc = 1; gargv[argc] != NULL; argc++) 174 free(gargv[argc]); 175 176 return (iop); 177 } 178 179 int 180 ftpd_pclose(iop) 181 FILE *iop; 182 { 183 int fdes, omask, status; 184 pid_t pid; 185 186 /* 187 * pclose returns -1 if stream is not associated with a 188 * `popened' command, or, if already `pclosed'. 189 */ 190 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 191 return (-1); 192 (void)fclose(iop); 193 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); 194 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 195 continue; 196 (void)sigsetmask(omask); 197 pids[fdes] = 0; 198 if (pid < 0) 199 return (pid); 200 if (WIFEXITED(status)) 201 return (WEXITSTATUS(status)); 202 return (1); 203 } 204