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 62 #define MAXUSRARGS 100 63 #define MAXGLOBARGS 1000 64 65 /* 66 * Special version of popen which avoids call to shell. This ensures noone 67 * may create a pipe to a hidden program as a side effect of a list or dir 68 * command. 69 */ 70 static int *pids; 71 static int fds; 72 73 FILE * 74 ftpd_popen(char *program, char *type) 75 { 76 char *cp; 77 FILE *iop; 78 int argc, gargc, pdes[2], pid; 79 char **pop, *argv[MAXUSRARGS], *gargv[MAXGLOBARGS]; 80 81 if (((*type != 'r') && (*type != 'w')) || type[1]) 82 return (NULL); 83 84 if (!pids) { 85 if ((fds = getdtablesize()) <= 0) 86 return (NULL); 87 if ((pids = (int *)malloc((u_int)(fds * sizeof(int)))) == NULL) 88 return (NULL); 89 memset(pids, 0, fds * sizeof(int)); 90 } 91 if (pipe(pdes) < 0) 92 return (NULL); 93 94 /* break up string into pieces */ 95 for (argc = 0, cp = program; argc < MAXUSRARGS; cp = NULL) { 96 if (!(argv[argc++] = strtok(cp, " \t\n"))) 97 break; 98 } 99 argv[argc - 1] = NULL; 100 101 /* glob each piece */ 102 gargv[0] = argv[0]; 103 for (gargc = argc = 1; argv[argc] && gargc < (MAXGLOBARGS-1); argc++) { 104 glob_t gl; 105 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE; 106 107 memset(&gl, 0, sizeof(gl)); 108 gl.gl_matchc = MAXGLOBARGS; 109 flags |= GLOB_LIMIT; 110 if (glob(argv[argc], flags, NULL, &gl)) 111 gargv[gargc++] = strdup(argv[argc]); 112 else 113 for (pop = gl.gl_pathv; *pop && gargc < (MAXGLOBARGS-1); 114 pop++) 115 gargv[gargc++] = strdup(*pop); 116 globfree(&gl); 117 } 118 gargv[gargc] = NULL; 119 120 iop = NULL; 121 fflush(NULL); 122 pid = (strcmp(gargv[0], _PATH_LS) == 0) ? fork() : vfork(); 123 switch(pid) { 124 case -1: /* error */ 125 (void)close(pdes[0]); 126 (void)close(pdes[1]); 127 goto pfree; 128 /* NOTREACHED */ 129 case 0: /* child */ 130 if (*type == 'r') { 131 if (pdes[1] != STDOUT_FILENO) { 132 dup2(pdes[1], STDOUT_FILENO); 133 (void)close(pdes[1]); 134 } 135 dup2(STDOUT_FILENO, STDERR_FILENO); /* stderr too! */ 136 (void)close(pdes[0]); 137 } else { 138 if (pdes[0] != STDIN_FILENO) { 139 dup2(pdes[0], STDIN_FILENO); 140 (void)close(pdes[0]); 141 } 142 (void)close(pdes[1]); 143 } 144 if (strcmp(gargv[0], _PATH_LS) == 0) { 145 /* Reset getopt for ls_main() */ 146 optreset = optind = optopt = 1; 147 /* Close syslogging to remove pwd.db missing msgs */ 148 closelog(); 149 /* Trigger to sense new /etc/localtime after chroot */ 150 if (getenv("TZ") == NULL) { 151 setenv("TZ", "", 0); 152 tzset(); 153 unsetenv("TZ"); 154 tzset(); 155 } 156 exit(ls_main(gargc, gargv)); 157 } 158 execv(gargv[0], gargv); 159 _exit(1); 160 } 161 /* parent; assume fdopen can't fail... */ 162 if (*type == 'r') { 163 iop = fdopen(pdes[0], type); 164 (void)close(pdes[1]); 165 } else { 166 iop = fdopen(pdes[1], type); 167 (void)close(pdes[0]); 168 } 169 pids[fileno(iop)] = pid; 170 171 pfree: for (argc = 1; gargv[argc] != NULL; argc++) 172 free(gargv[argc]); 173 174 return (iop); 175 } 176 177 int 178 ftpd_pclose(FILE *iop) 179 { 180 int fdes, omask, status; 181 pid_t pid; 182 183 /* 184 * pclose returns -1 if stream is not associated with a 185 * `popened' command, or, if already `pclosed'. 186 */ 187 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 188 return (-1); 189 (void)fclose(iop); 190 omask = sigblock(sigmask(SIGINT)|sigmask(SIGQUIT)|sigmask(SIGHUP)); 191 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 192 continue; 193 (void)sigsetmask(omask); 194 pids[fdes] = 0; 195 if (pid < 0) 196 return (pid); 197 if (WIFEXITED(status)) 198 return (WEXITSTATUS(status)); 199 return (1); 200 } 201