exec.c revision 78410
1235783Skib/*- 2235783Skib * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org> 3235783Skib * All rights reserved. 4235783Skib * 5235783Skib * Redistribution and use in source and binary forms, with or without 6235783Skib * modification, are permitted provided that the following conditions 7235783Skib * are met: 8235783Skib * 1. Redistributions of source code must retain the above copyright 9235783Skib * notice, this list of conditions and the following disclaimer. 10235783Skib * 2. Redistributions in binary form must reproduce the above copyright 11235783Skib * notice, this list of conditions and the following disclaimer in the 12235783Skib * documentation and/or other materials provided with the distribution. 13235783Skib * 14235783Skib * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15235783Skib * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16235783Skib * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17235783Skib * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18235783Skib * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19235783Skib * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20235783Skib * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21235783Skib * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22235783Skib * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23235783Skib * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24235783Skib * SUCH DAMAGE. 25235783Skib * 26235783Skib * $FreeBSD: head/usr.sbin/ppp/exec.c 78410 2001-06-18 14:59:36Z brian $ 27235783Skib */ 28235783Skib 29235783Skib#include <sys/param.h> 30235783Skib#include <sys/socket.h> 31235783Skib#include <sys/un.h> 32235783Skib 33235783Skib#include <errno.h> 34235783Skib#include <fcntl.h> 35235783Skib#include <stdio.h> 36235783Skib#include <stdlib.h> 37235783Skib#include <string.h> 38235783Skib#include <sys/wait.h> 39235783Skib#include <sys/uio.h> 40235783Skib#include <termios.h> 41235783Skib#include <unistd.h> 42235783Skib 43235783Skib#include "layer.h" 44235783Skib#include "defs.h" 45235783Skib#include "mbuf.h" 46235783Skib#include "log.h" 47235783Skib#include "timer.h" 48235783Skib#include "lqr.h" 49235783Skib#include "hdlc.h" 50235783Skib#include "throughput.h" 51235783Skib#include "fsm.h" 52235783Skib#include "lcp.h" 53235783Skib#include "ccp.h" 54235783Skib#include "link.h" 55235783Skib#include "async.h" 56235783Skib#include "descriptor.h" 57235783Skib#include "physical.h" 58235783Skib#include "mp.h" 59235783Skib#include "chat.h" 60235783Skib#include "command.h" 61235783Skib#include "auth.h" 62235783Skib#include "chap.h" 63235783Skib#include "cbcp.h" 64235783Skib#include "datalink.h" 65235783Skib#include "id.h" 66235783Skib#include "exec.h" 67235783Skib 68235783Skibstatic struct device execdevice = { 69235783Skib EXEC_DEVICE, 70235783Skib "exec", 71235783Skib 0, 72235783Skib { CD_NOTREQUIRED, 0 }, 73235783Skib NULL, 74235783Skib NULL, 75235783Skib NULL, 76235783Skib NULL, 77235783Skib NULL, 78235783Skib NULL, 79235783Skib NULL, 80235783Skib NULL, 81235783Skib NULL, 82235783Skib NULL, 83235783Skib NULL, 84235783Skib NULL 85235783Skib}; 86235783Skib 87235783Skibstruct device * 88235783Skibexec_iov2device(int type, struct physical *p, struct iovec *iov, 89235783Skib int *niov, int maxiov, int *auxfd, int *nauxfd) 90235783Skib{ 91235783Skib if (type == EXEC_DEVICE) { 92235783Skib free(iov[(*niov)++].iov_base); 93235783Skib physical_SetupStack(p, execdevice.name, PHYSICAL_NOFORCE); 94235783Skib return &execdevice; 95235783Skib } 96235783Skib 97235783Skib return NULL; 98235783Skib} 99235783Skib 100235783Skibstruct device * 101235783Skibexec_Create(struct physical *p) 102235783Skib{ 103235783Skib if (p->fd < 0 && *p->name.full == '!') { 104235783Skib int fids[2], type; 105235783Skib 106235783Skib p->fd--; /* We own the device but maybe can't use it - change fd */ 107235783Skib type = physical_IsSync(p) ? SOCK_DGRAM : SOCK_STREAM; 108235783Skib 109235783Skib if (socketpair(AF_UNIX, type, PF_UNSPEC, fids) < 0) 110235783Skib log_Printf(LogPHASE, "Unable to create pipe for line exec: %s\n", 111235783Skib strerror(errno)); 112235783Skib else { 113235783Skib static int child_status; /* This variable is abused ! */ 114235783Skib int stat, argc, i, ret, wret, pidpipe[2]; 115235783Skib pid_t pid, realpid; 116235783Skib char *argv[MAXARGS]; 117235783Skib 118235783Skib stat = fcntl(fids[0], F_GETFL, 0); 119235783Skib if (stat > 0) { 120235783Skib stat |= O_NONBLOCK; 121235783Skib fcntl(fids[0], F_SETFL, stat); 122235783Skib } 123235783Skib realpid = getpid(); 124235783Skib if (pipe(pidpipe) == -1) { 125235783Skib log_Printf(LogPHASE, "Unable to pipe for line exec: %s\n", 126235783Skib strerror(errno)); 127235783Skib close(fids[1]); 128235783Skib } else switch ((pid = fork())) { 129235783Skib case -1: 130271816Sdumbbell log_Printf(LogPHASE, "Unable to fork for line exec: %s\n", 131271816Sdumbbell strerror(errno)); 132271816Sdumbbell close(pidpipe[0]); 133271816Sdumbbell close(pidpipe[1]); 134271816Sdumbbell close(fids[1]); 135271816Sdumbbell break; 136271816Sdumbbell 137271816Sdumbbell case 0: 138271816Sdumbbell close(pidpipe[0]); 139271816Sdumbbell close(fids[0]); 140271816Sdumbbell timer_TermService(); 141271816Sdumbbell#ifndef NOSUID 142271816Sdumbbell setuid(ID0realuid()); 143271816Sdumbbell#endif 144271816Sdumbbell 145271816Sdumbbell child_status = 0; 146271816Sdumbbell switch ((pid = vfork())) { 147271816Sdumbbell case 0: 148235783Skib close(pidpipe[1]); 149235783Skib break; 150235783Skib 151235783Skib case -1: 152235783Skib ret = errno; 153235783Skib log_Printf(LogPHASE, "Unable to vfork to drop parent: %s\n", 154282199Sdumbbell strerror(errno)); 155235783Skib close(pidpipe[1]); 156254838Sdumbbell _exit(ret); 157254838Sdumbbell 158254838Sdumbbell default: 159235783Skib write(pidpipe[1], &pid, sizeof pid); 160235783Skib close(pidpipe[1]); 161235783Skib _exit(child_status); /* The error from exec() ! */ 162235783Skib } 163282199Sdumbbell 164235783Skib log_Printf(LogDEBUG, "Exec'ing ``%s''\n", p->name.base); 165235783Skib 166235783Skib if ((argc = MakeArgs(p->name.base, argv, VECSIZE(argv), 167235783Skib PARSE_REDUCE|PARSE_NOHASH)) < 0) { 168235783Skib log_Printf(LogWARN, "Syntax error in exec command\n"); 169235783Skib _exit(ESRCH); 170235783Skib } 171235783Skib 172235783Skib command_Expand(argv, argc, (char const *const *)argv, 173235783Skib p->dl->bundle, 0, realpid); 174235783Skib 175235783Skib dup2(fids[1], STDIN_FILENO); 176235783Skib dup2(fids[1], STDOUT_FILENO); 177235783Skib dup2(fids[1], STDERR_FILENO); 178235783Skib for (i = getdtablesize(); i > STDERR_FILENO; i--) 179235783Skib fcntl(i, F_SETFD, 1); 180235783Skib 181235783Skib execvp(*argv, argv); 182235783Skib child_status = errno; /* Only works for vfork() */ 183235783Skib printf("execvp failed: %s: %s\r\n", *argv, strerror(child_status)); 184235783Skib _exit(child_status); 185235783Skib break; 186235783Skib 187235783Skib default: 188235783Skib close(pidpipe[1]); 189235783Skib close(fids[1]); 190235783Skib if (read(pidpipe[0], &p->session_owner, sizeof p->session_owner) != 191235783Skib sizeof p->session_owner) 192235783Skib p->session_owner = (pid_t)-1; 193235783Skib close(pidpipe[0]); 194235783Skib while ((wret = waitpid(pid, &stat, 0)) == -1 && errno == EINTR) 195235783Skib ; 196235783Skib if (wret == -1) { 197235783Skib log_Printf(LogWARN, "Waiting for child process: %s\n", 198235783Skib strerror(errno)); 199235783Skib close(fids[0]); 200235783Skib p->session_owner = (pid_t)-1; 201235783Skib break; 202235783Skib } else if (WIFSIGNALED(stat)) { 203235783Skib log_Printf(LogWARN, "Child process received sig %d !\n", 204235783Skib WTERMSIG(stat)); 205235783Skib close(fids[0]); 206235783Skib p->session_owner = (pid_t)-1; 207235783Skib break; 208235783Skib } else if (WIFSTOPPED(stat)) { 209235783Skib log_Printf(LogWARN, "Child process received stop sig %d !\n", 210235783Skib WSTOPSIG(stat)); 211235783Skib /* I guess that's ok.... */ 212235783Skib } else if ((ret = WEXITSTATUS(stat))) { 213235783Skib log_Printf(LogWARN, "Cannot exec \"%s\": %s\n", p->name.base, 214235783Skib strerror(ret)); 215235783Skib close(fids[0]); 216235783Skib p->session_owner = (pid_t)-1; 217235783Skib break; 218235783Skib } 219235783Skib p->fd = fids[0]; 220235783Skib log_Printf(LogDEBUG, "Using descriptor %d for child\n", p->fd); 221235783Skib physical_SetupStack(p, execdevice.name, PHYSICAL_NOFORCE); 222235783Skib if (p->cfg.cd.necessity != CD_DEFAULT) 223235783Skib log_Printf(LogWARN, "Carrier settings ignored\n"); 224235783Skib return &execdevice; 225235783Skib } 226235783Skib close(fids[0]); 227235783Skib } 228235783Skib } 229235783Skib 230 return NULL; 231} 232