| /*- |
| * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org> |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * |
| * $FreeBSD: src/usr.sbin/ppp/exec.c,v 1.29.10.1.4.1 2010/12/21 17:10:29 kensmith Exp $ |
| */ |
| |
| #include <sys/param.h> |
| #include <sys/socket.h> |
| #include <sys/un.h> |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sysexits.h> |
| #include <sys/wait.h> |
| #include <sys/stat.h> |
| #include <sys/uio.h> |
| #include <termios.h> |
| #include <unistd.h> |
| |
| #include "layer.h" |
| #include "defs.h" |
| #include "mbuf.h" |
| #include "log.h" |
| #include "timer.h" |
| #include "lqr.h" |
| #include "hdlc.h" |
| #include "throughput.h" |
| #include "fsm.h" |
| #include "lcp.h" |
| #include "ccp.h" |
| #include "link.h" |
| #include "async.h" |
| #include "descriptor.h" |
| #include "physical.h" |
| #include "mp.h" |
| #include "chat.h" |
| #include "command.h" |
| #include "auth.h" |
| #include "chap.h" |
| #include "cbcp.h" |
| #include "datalink.h" |
| #include "id.h" |
| #include "main.h" |
| #include "exec.h" |
| |
| |
| struct execdevice { |
| struct device dev; /* What struct physical knows about */ |
| int fd_out; /* output descriptor */ |
| }; |
| |
| #define device2exec(d) ((d)->type == EXEC_DEVICE ? (struct execdevice *)d : NULL) |
| |
| unsigned |
| exec_DeviceSize(void) |
| { |
| return sizeof(struct execdevice); |
| } |
| |
| static void |
| exec_Free(struct physical *p) |
| { |
| struct execdevice *dev = device2exec(p->handler); |
| |
| if (dev->fd_out != -1) |
| close(dev->fd_out); |
| free(dev); |
| } |
| |
| static void |
| exec_device2iov(struct device *d, struct iovec *iov, int *niov, |
| int maxiov __unused, int *auxfd, int *nauxfd) |
| { |
| struct execdevice *dev; |
| int sz = physical_MaxDeviceSize(); |
| |
| iov[*niov].iov_base = d = realloc(d, sz); |
| if (d == NULL) { |
| log_Printf(LogALERT, "Failed to allocate memory: %d\n", sz); |
| AbortProgram(EX_OSERR); |
| } |
| iov[*niov].iov_len = sz; |
| (*niov)++; |
| |
| dev = device2exec(d); |
| if (dev->fd_out >= 0) { |
| *auxfd = dev->fd_out; |
| (*nauxfd)++; |
| } |
| } |
| |
| static int |
| exec_RemoveFromSet(struct physical *p, fd_set *r, fd_set *w, fd_set *e) |
| { |
| struct execdevice *dev = device2exec(p->handler); |
| int sets; |
| |
| p->handler->removefromset = NULL; |
| sets = physical_RemoveFromSet(p, r, w, e); |
| p->handler->removefromset = exec_RemoveFromSet; |
| |
| if (dev->fd_out >= 0) { |
| if (w && FD_ISSET(dev->fd_out, w)) { |
| FD_CLR(dev->fd_out, w); |
| log_Printf(LogTIMER, "%s: fdunset(w) %d\n", p->link.name, dev->fd_out); |
| sets++; |
| } |
| if (e && FD_ISSET(dev->fd_out, e)) { |
| FD_CLR(dev->fd_out, e); |
| log_Printf(LogTIMER, "%s: fdunset(e) %d\n", p->link.name, dev->fd_out); |
| sets++; |
| } |
| } |
| |
| return sets; |
| } |
| |
| static ssize_t |
| exec_Write(struct physical *p, const void *v, size_t n) |
| { |
| struct execdevice *dev = device2exec(p->handler); |
| int fd = dev->fd_out == -1 ? p->fd : dev->fd_out; |
| |
| return write(fd, v, n); |
| } |
| |
| static struct device baseexecdevice = { |
| EXEC_DEVICE, |
| "exec", |
| 0, |
| { CD_NOTREQUIRED, 0 }, |
| NULL, |
| exec_RemoveFromSet, |
| NULL, |
| NULL, |
| NULL, |
| NULL, |
| NULL, |
| exec_Free, |
| NULL, |
| exec_Write, |
| exec_device2iov, |
| NULL, |
| NULL, |
| NULL |
| }; |
| |
| struct device * |
| exec_iov2device(int type, struct physical *p, struct iovec *iov, |
| int *niov, int maxiov __unused, int *auxfd, int *nauxfd) |
| { |
| if (type == EXEC_DEVICE) { |
| struct execdevice *dev = (struct execdevice *)iov[(*niov)++].iov_base; |
| |
| dev = realloc(dev, sizeof *dev); /* Reduce to the correct size */ |
| if (dev == NULL) { |
| log_Printf(LogALERT, "Failed to allocate memory: %d\n", |
| (int)(sizeof *dev)); |
| AbortProgram(EX_OSERR); |
| } |
| |
| if (*nauxfd) { |
| dev->fd_out = *auxfd; |
| (*nauxfd)--; |
| } else |
| dev->fd_out = -1; |
| |
| /* Refresh function pointers etc */ |
| memcpy(&dev->dev, &baseexecdevice, sizeof dev->dev); |
| |
| physical_SetupStack(p, dev->dev.name, PHYSICAL_NOFORCE); |
| return &dev->dev; |
| } |
| |
| return NULL; |
| } |
| |
| static int |
| exec_UpdateSet(struct fdescriptor *d, fd_set *r, fd_set *w, fd_set *e, int *n) |
| { |
| struct physical *p = descriptor2physical(d); |
| struct execdevice *dev = device2exec(p->handler); |
| int result = 0; |
| |
| if (w && dev->fd_out >= 0) { |
| FD_SET(dev->fd_out, w); |
| log_Printf(LogTIMER, "%s: fdset(w) %d\n", p->link.name, dev->fd_out); |
| result++; |
| w = NULL; |
| } |
| |
| if (e && dev->fd_out >= 0) { |
| FD_SET(dev->fd_out, e); |
| log_Printf(LogTIMER, "%s: fdset(e) %d\n", p->link.name, dev->fd_out); |
| result++; |
| } |
| |
| if (result && *n <= dev->fd_out) |
| *n = dev->fd_out + 1; |
| |
| return result + physical_doUpdateSet(d, r, w, e, n, 0); |
| } |
| |
| static int |
| exec_IsSet(struct fdescriptor *d, const fd_set *fdset) |
| { |
| struct physical *p = descriptor2physical(d); |
| struct execdevice *dev = device2exec(p->handler); |
| int result = dev->fd_out >= 0 && FD_ISSET(dev->fd_out, fdset); |
| result += physical_IsSet(d, fdset); |
| |
| return result; |
| } |
| |
| struct device * |
| exec_Create(struct physical *p) |
| { |
| struct execdevice *dev; |
| |
| dev = NULL; |
| if (p->fd < 0) { |
| if (*p->name.full == '!') { |
| int fids[2], type; |
| |
| if ((dev = malloc(sizeof *dev)) == NULL) { |
| log_Printf(LogWARN, "%s: Cannot allocate an exec device: %s\n", |
| p->link.name, strerror(errno)); |
| return NULL; |
| } |
| dev->fd_out = -1; |
| |
| p->fd--; /* We own the device but maybe can't use it - change fd */ |
| type = physical_IsSync(p) ? SOCK_DGRAM : SOCK_STREAM; |
| |
| if (socketpair(AF_UNIX, type, PF_UNSPEC, fids) < 0) { |
| log_Printf(LogPHASE, "Unable to create pipe for line exec: %s\n", |
| strerror(errno)); |
| free(dev); |
| dev = NULL; |
| } else { |
| static int child_status; /* This variable is abused ! */ |
| int stat, argc, i, ret, wret, pidpipe[2]; |
| pid_t pid, realpid; |
| char *argv[MAXARGS]; |
| |
| stat = fcntl(fids[0], F_GETFL, 0); |
| if (stat > 0) { |
| stat |= O_NONBLOCK; |
| fcntl(fids[0], F_SETFL, stat); |
| } |
| realpid = getpid(); |
| if (pipe(pidpipe) == -1) { |
| log_Printf(LogPHASE, "Unable to pipe for line exec: %s\n", |
| strerror(errno)); |
| close(fids[1]); |
| close(fids[0]); |
| free(dev); |
| dev = NULL; |
| } else switch ((pid = fork())) { |
| case -1: |
| log_Printf(LogPHASE, "Unable to fork for line exec: %s\n", |
| strerror(errno)); |
| close(pidpipe[0]); |
| close(pidpipe[1]); |
| close(fids[1]); |
| close(fids[0]); |
| break; |
| |
| case 0: |
| close(pidpipe[0]); |
| close(fids[0]); |
| timer_TermService(); |
| #ifndef NOSUID |
| setuid(ID0realuid()); |
| #endif |
| |
| child_status = 0; |
| switch ((pid = vfork())) { |
| case 0: |
| close(pidpipe[1]); |
| break; |
| |
| case -1: |
| ret = errno; |
| log_Printf(LogPHASE, "Unable to vfork to drop parent: %s\n", |
| strerror(errno)); |
| close(pidpipe[1]); |
| _exit(ret); |
| |
| default: |
| write(pidpipe[1], &pid, sizeof pid); |
| close(pidpipe[1]); |
| _exit(child_status); /* The error from exec() ! */ |
| } |
| |
| log_Printf(LogDEBUG, "Exec'ing ``%s''\n", p->name.base); |
| |
| if ((argc = MakeArgs(p->name.base, argv, VECSIZE(argv), |
| PARSE_REDUCE|PARSE_NOHASH)) < 0) { |
| log_Printf(LogWARN, "Syntax error in exec command\n"); |
| _exit(ESRCH); |
| } |
| |
| command_Expand(argv, argc, (char const *const *)argv, |
| p->dl->bundle, 0, realpid); |
| |
| dup2(fids[1], STDIN_FILENO); |
| dup2(fids[1], STDOUT_FILENO); |
| dup2(fids[1], STDERR_FILENO); |
| for (i = getdtablesize(); i > STDERR_FILENO; i--) |
| fcntl(i, F_SETFD, 1); |
| |
| execvp(*argv, argv); |
| child_status = errno; /* Only works for vfork() */ |
| printf("execvp failed: %s: %s\r\n", *argv, strerror(child_status)); |
| _exit(child_status); |
| break; |
| |
| default: |
| close(pidpipe[1]); |
| close(fids[1]); |
| if (read(pidpipe[0], &p->session_owner, sizeof p->session_owner) != |
| sizeof p->session_owner) |
| p->session_owner = (pid_t)-1; |
| close(pidpipe[0]); |
| while ((wret = waitpid(pid, &stat, 0)) == -1 && errno == EINTR) |
| ; |
| if (wret == -1) { |
| log_Printf(LogWARN, "Waiting for child process: %s\n", |
| strerror(errno)); |
| close(fids[0]); |
| p->session_owner = (pid_t)-1; |
| break; |
| } else if (WIFSIGNALED(stat)) { |
| log_Printf(LogWARN, "Child process received sig %d !\n", |
| WTERMSIG(stat)); |
| close(fids[0]); |
| p->session_owner = (pid_t)-1; |
| break; |
| } else if (WIFSTOPPED(stat)) { |
| log_Printf(LogWARN, "Child process received stop sig %d !\n", |
| WSTOPSIG(stat)); |
| /* I guess that's ok.... */ |
| } else if ((ret = WEXITSTATUS(stat))) { |
| log_Printf(LogWARN, "Cannot exec \"%s\": %s\n", p->name.base, |
| strerror(ret)); |
| close(fids[0]); |
| p->session_owner = (pid_t)-1; |
| break; |
| } |
| p->fd = fids[0]; |
| log_Printf(LogDEBUG, "Using descriptor %d for child\n", p->fd); |
| } |
| } |
| } |
| } else { |
| struct stat st; |
| |
| if (fstat(p->fd, &st) != -1 && (st.st_mode & S_IFIFO)) { |
| if ((dev = malloc(sizeof *dev)) == NULL) |
| log_Printf(LogWARN, "%s: Cannot allocate an exec device: %s\n", |
| p->link.name, strerror(errno)); |
| else if (p->fd == STDIN_FILENO) { |
| log_Printf(LogPHASE, "%s: Using stdin/stdout to communicate with " |
| "parent (pipe mode)\n", p->link.name); |
| dev->fd_out = dup(STDOUT_FILENO); |
| |
| /* Hook things up so that we monitor dev->fd_out */ |
| p->desc.UpdateSet = exec_UpdateSet; |
| p->desc.IsSet = exec_IsSet; |
| } else |
| dev->fd_out = -1; |
| } |
| } |
| |
| if (dev) { |
| memcpy(&dev->dev, &baseexecdevice, sizeof dev->dev); |
| physical_SetupStack(p, dev->dev.name, PHYSICAL_NOFORCE); |
| if (p->cfg.cd.necessity != CD_DEFAULT) |
| log_Printf(LogWARN, "Carrier settings ignored\n"); |
| return &dev->dev; |
| } |
| |
| return NULL; |
| } |
