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#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <signal.h>
#include <fcntl.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <grp.h>
#include <sys/wait.h>
#include <netax25/axlib.h>
#include <netax25/axconfig.h>
#include "node.h"
#define ECMD_PIPE 1 /* Run through pipe */
#define ECMD_RECONN 2 /* */
static int norm_extcmd(struct cmd *cmdp, char **argv)
{
int pid;
alarm(0L);
pid = fork();
if (pid == -1) {
/* fork error */
node_perror("norm_extcmd: fork", errno);
return 0;
}
if (pid == 0) {
/* child */
setgroups(0, NULL);
setgid(cmdp->gid);
setuid(cmdp->uid);
execve(cmdp->path, argv, NULL);
node_perror("norm_extcmd: execve", errno);
exit(1);
}
/* parent */
waitpid(pid, NULL, 0);
return 0;
}
static int pipe_extcmd(struct cmd *cmdp, char **argv)
{
ax25io *iop;
int pipe_in[2], pipe_out[2];
int maxfd, pid, c;
fd_set rdfdset, wrfdset;
int pend_nodew = -1, pend_pipew = -1;
if (pipe(pipe_in) == -1) {
node_perror("pipe_extcmd: pipe_in", errno);
return 0;
}
if (pipe(pipe_out) == -1) {
node_perror("pipe_extcmd: pipe_out", errno);
return 0;
}
signal(SIGCHLD, SIG_IGN);
pid = fork();
if (pid == -1) { /* fork error */
node_perror("pipe_extcmd: fork", errno);
signal(SIGCHLD, SIG_DFL);
return 0;
}
if (pid == 0) { /* child */
/*
* Redirect childs output to the pipes closing
* stdin/out/err as we go.
*/
dup2(pipe_in[0], STDIN_FILENO);
dup2(pipe_out[1], STDOUT_FILENO);
dup2(pipe_out[1], STDERR_FILENO);
/* Close the other ends */
close(pipe_in[1]);
close(pipe_out[0]);
/* Set uid, gid and supplementary groups */
setgroups(0, NULL);
setgid(cmdp->gid);
setuid(cmdp->uid);
execve(cmdp->path, argv, NULL);
perror("pipe_extcmd: execve");
exit(1);
}
/* parent */
close(pipe_in[0]);
close(pipe_out[1]);
iop = axio_init(pipe_out[0], pipe_in[1], 1024, UNSPEC_EOL);
if (iop == NULL) {
node_perror("pipe_extcmd: Error initializing I/O", -1);
signal(SIGCHLD, SIG_DFL);
kill(pid, SIGKILL);
return 0;
}
node_set_nonblock(NodeIo, 1);
node_set_nonblock(iop, 1);
maxfd = NodeIo->ifd;
maxfd = MAX(maxfd, NodeIo->ofd);
maxfd = MAX(maxfd, iop->ifd);
maxfd = MAX(maxfd, iop->ofd);
maxfd++;
while (1) {
FD_ZERO(&rdfdset);
FD_ZERO(&wrfdset);
FD_SET(NodeIo->ifd, &rdfdset);
FD_SET(iop->ifd, &rdfdset);
if (pend_nodew != -1)
FD_SET(NodeIo->ofd, &wrfdset);
if (pend_pipew != -1)
FD_SET(iop->ofd, &wrfdset);
if (select(maxfd, &rdfdset, &wrfdset, NULL, NULL) == -1) {
node_perror("pipe_extcmd: select", errno);
break;
}
/* Try to write pending char to pipe */
if (pend_pipew != -1) {
if (axio_putc(pend_pipew, iop) != -1)
pend_pipew = -1;
else if (errno != EAGAIN)
break;
}
/* If nothing is pending we can try to get new data */
if (pend_pipew == -1) {
while ((c = axio_getc(NodeIo)) != -1) {
alarm(ConnTimeout);
if (axio_putc(c, iop) == -1) {
pend_pipew = c;
break;
}
}
if (errno != EAGAIN)
break;
}
/* Try to write pending char to node connection */
if (pend_nodew != -1) {
if (axio_putc(pend_nodew, NodeIo) != -1)
pend_nodew = -1;
else if (errno != EAGAIN)
break;
}
/* If nothing is pending we can try to get new data */
if (pend_nodew == -1) {
while ((c = axio_getc(iop)) != -1) {
alarm(ConnTimeout);
if (axio_putc(c, NodeIo) == -1) {
pend_nodew = c;
break;
}
}
if (errno != EAGAIN) {
if (errno)
node_msg("%s", strerror(errno));
break;
}
}
/* blocking flush */
if (node_flush(NodeIo) == -1)
break;
if (node_flush(iop) == -1)
break;
}
node_set_nonblock(NodeIo, 0);
node_set_nonblock(iop, 0);
axio_end(iop);
signal(SIGCHLD, SIG_DFL);
kill(pid, SIGKILL);
return 0;
}
int extcmd(struct cmd *cmdp, char **argv)
{
int ret;
User.state = STATE_EXTCMD;
User.dl_type = AF_UNSPEC;
strcpy(User.dl_name, cmdp->name);
strupr(User.dl_name);
update_user();
if (cmdp->flags & ECMD_PIPE)
ret = pipe_extcmd(cmdp, argv);
else
ret = norm_extcmd(cmdp, argv);
if (cmdp->flags & ECMD_RECONN)
node_msg("Reconnected to %s", HostName);
return ret;
}
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