1 /*- 2 * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $Id: exec.c,v 1.5 1999/06/05 21:35:50 brian Exp $ 27 */ 28 29 #include <sys/param.h> 30 #include <sys/socket.h> 31 #include <netinet/in.h> 32 #include <arpa/inet.h> 33 #include <netdb.h> 34 #include <netinet/in_systm.h> 35 #include <netinet/ip.h> 36 #include <sys/un.h> 37 38 #include <errno.h> 39 #include <fcntl.h> 40 #include <stdio.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include <sys/wait.h> 44 #include <sys/uio.h> 45 #include <termios.h> 46 #include <unistd.h> 47 48 #include "layer.h" 49 #include "defs.h" 50 #include "mbuf.h" 51 #include "log.h" 52 #include "sync.h" 53 #include "timer.h" 54 #include "lqr.h" 55 #include "hdlc.h" 56 #include "throughput.h" 57 #include "fsm.h" 58 #include "lcp.h" 59 #include "ccp.h" 60 #include "link.h" 61 #include "async.h" 62 #include "slcompress.h" 63 #include "iplist.h" 64 #include "ipcp.h" 65 #include "filter.h" 66 #include "descriptor.h" 67 #include "physical.h" 68 #include "mp.h" 69 #ifndef NORADIUS 70 #include "radius.h" 71 #endif 72 #include "chat.h" 73 #include "command.h" 74 #include "bundle.h" 75 #include "prompt.h" 76 #include "auth.h" 77 #include "chap.h" 78 #include "cbcp.h" 79 #include "datalink.h" 80 #include "exec.h" 81 82 static struct device execdevice = { 83 EXEC_DEVICE, 84 "exec", 85 NULL, 86 NULL, 87 NULL, 88 NULL, 89 NULL, 90 NULL, 91 NULL, 92 NULL, 93 NULL, 94 NULL 95 }; 96 97 struct device * 98 exec_iov2device(int type, struct physical *p, struct iovec *iov, 99 int *niov, int maxiov) 100 { 101 if (type == EXEC_DEVICE) { 102 free(iov[(*niov)++].iov_base); 103 physical_SetupStack(p, execdevice.name, PHYSICAL_FORCE_ASYNC); 104 return &execdevice; 105 } 106 107 return NULL; 108 } 109 110 struct device * 111 exec_Create(struct physical *p) 112 { 113 if (p->fd < 0 && *p->name.full == '!') { 114 int fids[2]; 115 116 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, fids) < 0) 117 log_Printf(LogPHASE, "Unable to create pipe for line exec: %s\n", 118 strerror(errno)); 119 else { 120 int stat, argc; 121 pid_t pid, realpid; 122 char *argv[MAXARGS]; 123 124 stat = fcntl(fids[0], F_GETFL, 0); 125 if (stat > 0) { 126 stat |= O_NONBLOCK; 127 fcntl(fids[0], F_SETFL, stat); 128 } 129 realpid = getpid(); 130 switch ((pid = fork())) { 131 case -1: 132 log_Printf(LogPHASE, "Unable to create pipe for line exec: %s\n", 133 strerror(errno)); 134 break; 135 136 case 0: 137 close(fids[0]); 138 timer_TermService(); 139 setuid(geteuid()); 140 141 switch (fork()) { 142 case 0: 143 break; 144 145 case -1: 146 log_Printf(LogPHASE, "Unable to fork to drop parent: %s\n", 147 strerror(errno)); 148 default: 149 _exit(127); 150 } 151 152 fids[1] = fcntl(fids[1], F_DUPFD, 3); 153 dup2(fids[1], STDIN_FILENO); 154 dup2(fids[1], STDOUT_FILENO); 155 dup2(fids[1], STDERR_FILENO); 156 157 log_Printf(LogDEBUG, "Exec'ing ``%s''\n", p->name.base); 158 argc = MakeArgs(p->name.base, argv, VECSIZE(argv)); 159 command_Expand(argv, argc, (char const *const *)argv, 160 p->dl->bundle, 0, realpid); 161 execvp(*argv, argv); 162 fprintf(stderr, "execvp failed: %s: %s\r\n", *argv, strerror(errno)); 163 _exit(127); 164 break; 165 166 default: 167 close(fids[1]); 168 p->fd = fids[0]; 169 waitpid(pid, &stat, 0); 170 log_Printf(LogDEBUG, "Using descriptor %d for child\n", p->fd); 171 physical_SetupStack(p, execdevice.name, PHYSICAL_FORCE_ASYNC); 172 return &execdevice; 173 } 174 } 175 } 176 177 return NULL; 178 } 179