upstream: disallow empty incoming filename or ones that refer to the

current directory; based on report/patch from Harry Sintonen

OpenBSD-Commit-ID: f27651b30eaee2df49540ab68d030865c04f6de9
do_cmd2(char *host, char *remuser, int port, char *cmd, int fdin, int fdout)
{
	pid_t pid;
	int status;

	if (verbose_mode)
		fmprintf(stderr,
		    "Executing: 2nd program %s host %s, user %s, command %s\n",
		    ssh_program, host,
		    remuser ? remuser : "(unspecified)", cmd);

	if (port == -1)
		port = sshport;

	/* Fork a child to execute the command on the remote host using ssh. */
	pid = fork();
	if (pid == 0) {
		dup2(fdin, 0);
		dup2(fdout, 1);

		replacearg(&args, 0, "%s", ssh_program);
		if (port != -1) {
			addargs(&args, "-p");
			addargs(&args, "%d", port);
		}
		if (remuser != NULL) {
			addargs(&args, "-l");
			addargs(&args, "%s", remuser);
		}
		addargs(&args, "--");
		addargs(&args, "%s", host);
		addargs(&args, "%s", cmd);

		execvp(ssh_program, args.list);
		perror(ssh_program);
		exit(1);
	} else if (pid == -1) {
		fatal("fork: %s", strerror(errno));
	}
	while (waitpid(pid, &status, 0) == -1)
		if (errno != EINTR)
			fatal("do_cmd2: waitpid: %s", strerror(errno));
	return 0;
}

do_cmd2(char *host, char *remuser, int port, char *cmd, int fdin, int fdout)
{
	pid_t pid;
	int status;

	if (verbose_mode)
		fmprintf(stderr,
		    "Executing: 2nd program %s host %s, user %s, command %s\n",
		    ssh_program, host,
		    remuser ? remuser : "(unspecified)", cmd);

	if (port == -1)
		port = sshport;

	/* Fork a child to execute the command on the remote host using ssh. */
	pid = fork();
	if (pid == 0) {
		dup2(fdin, 0);
		dup2(fdout, 1);

		replacearg(&args, 0, "%s", ssh_program);
		if (port != -1) {
			addargs(&args, "-p");
			addargs(&args, "%d", port);
		}
		if (remuser != NULL) {
			addargs(&args, "-l");
			addargs(&args, "%s", remuser);
		}
		addargs(&args, "--");
		addargs(&args, "%s", host);
		addargs(&args, "%s", cmd);

		execvp(ssh_program, args.list);
		perror(ssh_program);
		exit(1);
	} else if (pid == -1) {
		fatal("fork: %s", strerror(errno));
	}
	while (waitpid(pid, &status, 0) == -1)
		if (errno != EINTR)
			fatal("do_cmd2: waitpid: %s", strerror(errno));
	return 0;
}
