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 38 #ifdef HAVE_CONFIG_H 39 #include <config.h> 40 RCSID("$Id: popen.c,v 1.24 2001/03/26 11:41:02 assar Exp $"); 41 #endif 42 43 #include <sys/types.h> 44 #ifdef TIME_WITH_SYS_TIME 45 #include <sys/time.h> 46 #include <time.h> 47 #elif defined(HAVE_SYS_TIME_H) 48 #include <sys/time.h> 49 #else 50 #include <time.h> 51 #endif 52 #ifdef HAVE_SYS_RESOURCE_H 53 #include <sys/resource.h> 54 #endif 55 #include <sys/wait.h> 56 57 #include <errno.h> 58 #include <glob.h> 59 #include <signal.h> 60 #include <stdio.h> 61 #include <stdlib.h> 62 #include <string.h> 63 #include <unistd.h> 64 #include <roken.h> 65 #include "extern.h" 66 67 68 /* 69 * Special version of popen which avoids call to shell. This ensures 70 * no one may create a pipe to a hidden program as a side effect of a 71 * list or dir command. 72 */ 73 static int *pids; 74 static int fds; 75 76 extern int dochroot; 77 78 /* return path prepended with ~ftp if that file exists, otherwise 79 * return path unchanged 80 */ 81 82 const char * 83 ftp_rooted(const char *path) 84 { 85 static char home[MaxPathLen] = ""; 86 static char newpath[MaxPathLen]; 87 struct passwd *pwd; 88 89 if(!home[0]) 90 if((pwd = k_getpwnam("ftp"))) 91 strlcpy(home, pwd->pw_dir, sizeof(home)); 92 snprintf(newpath, sizeof(newpath), "%s/%s", home, path); 93 if(access(newpath, X_OK)) 94 strlcpy(newpath, path, sizeof(newpath)); 95 return newpath; 96 } 97 98 99 #define MAXARGS 100 100 #define MAXGLOBS 1000 101 102 FILE * 103 ftpd_popen(char *program, char *type, int do_stderr, int no_glob) 104 { 105 char *cp; 106 FILE *iop; 107 int argc, gargc, pdes[2], pid; 108 char **pop, *argv[MAXARGS], *gargv[MAXGLOBS]; 109 char *foo; 110 111 if (strcmp(type, "r") && strcmp(type, "w")) 112 return (NULL); 113 114 if (!pids) { 115 116 /* This function is ugly and should be rewritten, in 117 * modern unices there is no such thing as a maximum 118 * filedescriptor. 119 */ 120 121 fds = getdtablesize(); 122 pids = (int*)calloc(fds, sizeof(int)); 123 if(!pids) 124 return NULL; 125 } 126 if (pipe(pdes) < 0) 127 return (NULL); 128 129 /* break up string into pieces */ 130 foo = NULL; 131 for (argc = 0, cp = program; argc < MAXARGS - 1; cp = NULL) { 132 if (!(argv[argc++] = strtok_r(cp, " \t\n", &foo))) 133 break; 134 } 135 argv[MAXARGS - 1] = NULL; 136 137 gargv[0] = (char*)ftp_rooted(argv[0]); 138 /* glob each piece */ 139 for (gargc = argc = 1; argv[argc] && gargc < MAXGLOBS - 1; argc++) { 140 glob_t gl; 141 int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE 142 | GLOB_LIMIT; 143 144 memset(&gl, 0, sizeof(gl)); 145 if (no_glob || glob(argv[argc], flags, NULL, &gl)) 146 gargv[gargc++] = strdup(argv[argc]); 147 else 148 for (pop = gl.gl_pathv; 149 *pop && gargc < MAXGLOBS - 1; 150 pop++) 151 gargv[gargc++] = strdup(*pop); 152 globfree(&gl); 153 } 154 gargv[gargc] = NULL; 155 156 iop = NULL; 157 switch(pid = fork()) { 158 case -1: /* error */ 159 close(pdes[0]); 160 close(pdes[1]); 161 goto pfree; 162 /* NOTREACHED */ 163 case 0: /* child */ 164 if (*type == 'r') { 165 if (pdes[1] != STDOUT_FILENO) { 166 dup2(pdes[1], STDOUT_FILENO); 167 close(pdes[1]); 168 } 169 if(do_stderr) 170 dup2(STDOUT_FILENO, STDERR_FILENO); 171 close(pdes[0]); 172 } else { 173 if (pdes[0] != STDIN_FILENO) { 174 dup2(pdes[0], STDIN_FILENO); 175 close(pdes[0]); 176 } 177 close(pdes[1]); 178 } 179 execv(gargv[0], gargv); 180 gargv[0] = argv[0]; 181 execv(gargv[0], gargv); 182 _exit(1); 183 } 184 /* parent; assume fdopen can't fail... */ 185 if (*type == 'r') { 186 iop = fdopen(pdes[0], type); 187 close(pdes[1]); 188 } else { 189 iop = fdopen(pdes[1], type); 190 close(pdes[0]); 191 } 192 pids[fileno(iop)] = pid; 193 194 pfree: 195 for (argc = 1; gargv[argc] != NULL; argc++) 196 free(gargv[argc]); 197 198 199 return (iop); 200 } 201 202 int 203 ftpd_pclose(FILE *iop) 204 { 205 int fdes, status; 206 pid_t pid; 207 sigset_t sigset, osigset; 208 209 /* 210 * pclose returns -1 if stream is not associated with a 211 * `popened' command, or, if already `pclosed'. 212 */ 213 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 214 return (-1); 215 fclose(iop); 216 sigemptyset(&sigset); 217 sigaddset(&sigset, SIGINT); 218 sigaddset(&sigset, SIGQUIT); 219 sigaddset(&sigset, SIGHUP); 220 sigprocmask(SIG_BLOCK, &sigset, &osigset); 221 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 222 continue; 223 sigprocmask(SIG_SETMASK, &osigset, NULL); 224 pids[fdes] = 0; 225 if (pid < 0) 226 return (pid); 227 if (WIFEXITED(status)) 228 return (WEXITSTATUS(status)); 229 return (1); 230 } 231