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 1.26 2002/04/02 11:57:39 joda 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 | 143 #ifdef GLOB_MAXPATH 144 GLOB_MAXPATH 145 #else 146 GLOB_LIMIT 147 #endif 148 ; 149 150 memset(&gl, 0, sizeof(gl)); 151 if (no_glob || 152 glob(argv[argc], flags, NULL, &gl) || 153 gl.gl_pathc == 0) 154 gargv[gargc++] = strdup(argv[argc]); 155 else 156 for (pop = gl.gl_pathv; 157 *pop && gargc < MAXGLOBS - 1; 158 pop++) 159 gargv[gargc++] = strdup(*pop); 160 globfree(&gl); 161 } 162 gargv[gargc] = NULL; 163 164 iop = NULL; 165 switch(pid = fork()) { 166 case -1: /* error */ 167 close(pdes[0]); 168 close(pdes[1]); 169 goto pfree; 170 /* NOTREACHED */ 171 case 0: /* child */ 172 if (*type == 'r') { 173 if (pdes[1] != STDOUT_FILENO) { 174 dup2(pdes[1], STDOUT_FILENO); 175 close(pdes[1]); 176 } 177 if(do_stderr) 178 dup2(STDOUT_FILENO, STDERR_FILENO); 179 close(pdes[0]); 180 } else { 181 if (pdes[0] != STDIN_FILENO) { 182 dup2(pdes[0], STDIN_FILENO); 183 close(pdes[0]); 184 } 185 close(pdes[1]); 186 } 187 execv(gargv[0], gargv); 188 gargv[0] = argv[0]; 189 execv(gargv[0], gargv); 190 _exit(1); 191 } 192 /* parent; assume fdopen can't fail... */ 193 if (*type == 'r') { 194 iop = fdopen(pdes[0], type); 195 close(pdes[1]); 196 } else { 197 iop = fdopen(pdes[1], type); 198 close(pdes[0]); 199 } 200 pids[fileno(iop)] = pid; 201 202 pfree: 203 for (argc = 1; gargv[argc] != NULL; argc++) 204 free(gargv[argc]); 205 206 207 return (iop); 208 } 209 210 int 211 ftpd_pclose(FILE *iop) 212 { 213 int fdes, status; 214 pid_t pid; 215 sigset_t sigset, osigset; 216 217 /* 218 * pclose returns -1 if stream is not associated with a 219 * `popened' command, or, if already `pclosed'. 220 */ 221 if (pids == 0 || pids[fdes = fileno(iop)] == 0) 222 return (-1); 223 fclose(iop); 224 sigemptyset(&sigset); 225 sigaddset(&sigset, SIGINT); 226 sigaddset(&sigset, SIGQUIT); 227 sigaddset(&sigset, SIGHUP); 228 sigprocmask(SIG_BLOCK, &sigset, &osigset); 229 while ((pid = waitpid(pids[fdes], &status, 0)) < 0 && errno == EINTR) 230 continue; 231 sigprocmask(SIG_SETMASK, &osigset, NULL); 232 pids[fdes] = 0; 233 if (pid < 0) 234 return (pid); 235 if (WIFEXITED(status)) 236 return (WEXITSTATUS(status)); 237 return (1); 238 } 239