Subversion Repositories planix.SVN

/* screenlock - lock a terminal */

#include <u.h>

#include <libc.h>

#include <libsec.h>

#include <draw.h>

#include <thread.h>

#include <auth.h>

char pic[] = "/lib/bunny.bit";

int vgactl;

int debug;

int doblank;

int chatty = 0;

char user[256];

void

blankscreen(int blank)

{

	if(vgactl < 0)

		return;

	seek(vgactl, 0, 0);

	if(fprint(vgactl, blank? "blank": "unblank") < 0)

		fprint(2, "blankscreen: can't blank: %r\n");

}

void

error(char *fmt, ...)

{

	Fmt f;

	char buf[64];

	va_list arg;

	fmtfdinit(&f, 1, buf, sizeof buf);

	fmtprint(&f, "screenlock: ");

	va_start(arg, fmt);

	fmtvprint(&f, fmt, arg);

	va_end(arg);

	fmtprint(&f, "\n");

	fmtfdflush(&f);

	threadexitsall("fatal error");

}

void

usage(void)

{

	fprint(2, "usage: %s\n", argv0);

	exits("usage");

}

void

readfile(char *name, char *buf, int nbuf, int addnul)

{

	int fd;

	fd = open(name, OREAD);

	if(fd == -1)

		error("%s - can't open: %r", name);

	nbuf = read(fd, buf, nbuf-addnul);

	close(fd);

	if(nbuf == -1)

		error("%s - can't can't read: %r", name);

	if(addnul)

		buf[nbuf] = '\0';

}

void

readline(char *buf, int nbuf)

{

	char c;

	int i;

	i = 0;

	while(i < nbuf-1)

		if(read(0, &c, 1) != 1 || c == '\04' || c == '\177'){

			i = 0;

			break;

		} else if(c == '\n')

			break;

		else if(c == '\b' && i > 0)

			--i;

		else if(c == ('u' & 037))

			i = 0;

		else

			buf[i++] = c;

	buf[i] = '\0';

}

void

checkpassword(void)

{

	int fd, consctl, must;

	char buf[256];

	AuthInfo *ai;

	static int opened;

	must = 1;

	if(!opened){

		fd = open("/dev/cons", OREAD);

		if(fd == -1)

			error("can't open cons: %r");

		dup(fd, 0);

		close(fd);

		fd = open("/dev/cons", OWRITE);

		if(fd == -1)

			error("can't open cons: %r");

		dup(fd, 1);

		dup(1, 2);

		close(fd);

		consctl = open("/dev/consctl", OWRITE);

		if(consctl == -1)

			error("can't open consctl: %r");

		if(write(consctl, "rawon", 5) != 5)

			error("can't turn off echo\n");

		opened = 1;

	}

	for(;;){

		if(chatty || !must)

			fprint(2, "%s's screenlock password: ", user);

		memset(buf, 0, sizeof buf);

		readline(buf, sizeof buf);

		blankscreen(0);

		if(chatty || !must)

			fprint(2, "\n");

		if(buf[0] == '\0' || buf[0] == '\04'){

			if(must)

				continue;

			error("no password typed");

		}

		/* authenticate */

		ai = auth_userpasswd(user, buf);

		if(ai != nil && ai->cap != nil)

			break;

		auth_freeAI(ai);

		if(chatty || !must)

			fprint(2, "password mismatch\n");

		doblank = 1;

	}

	memset(buf, 0, sizeof buf);

	blankscreen(0);

}

void

blanker(void *)

{

	int tics;

	tics = 0;

	for(;;){

		if(doblank > 0){

			doblank = 0;

			tics = 10;

		}

		if(tics > 0 && --tics == 0)

			blankscreen(1);

		sleep(1000);

	}

}

void

grabmouse(void*)

{

	int fd, x, y;

	char ibuf[256], obuf[256];

	if(debug)

		return;

	fd = open("/dev/mouse", ORDWR);

	if(fd < 0)

		error("can't open /dev/mouse: %r");

	snprint(obuf, sizeof obuf, "m %d %d",

		screen->r.min.x + Dx(screen->r)/2,

		screen->r.min.y + Dy(screen->r)/2);

	while(read(fd, ibuf, sizeof ibuf) > 0){

		ibuf[12] = 0;

		ibuf[24] = 0;

		x = atoi(ibuf+1);

		y = atoi(ibuf+13);

		if(x != screen->r.min.x + Dx(screen->r)/2 ||

		   y != screen->r.min.y + Dy(screen->r)/2){

			fprint(fd, "%s", obuf);

			doblank = 1;

		}

	}

}

/* lay down text at `p' */

static void

screenstring(Point p, char *s)

{

	string(screen, p, screen->display->white, ZP, font, s);

	flushimage(display, 1);

}

void

lockscreen(void)

{

	enum { Nfld = 5, Fldlen = 12, Cursorlen = 2*4 + 2*2*16, };

	char *s;

	char buf[Nfld*Fldlen], *flds[Nfld], newcmd[128], cbuf[Cursorlen];

	int fd, dx, dy;

	Image *i;

	Point p;

	Rectangle r;

	Tm *tm;

	fd = open("/dev/screen", OREAD);

	if(fd < 0)

		error("can't open /dev/screen: %r");

	if(read(fd, buf, Nfld*Fldlen) != Nfld*Fldlen)

		error("can't read /dev/screen: %r");

	close(fd);

	buf[sizeof buf-1] = 0;

	if(tokenize(buf, flds, Nfld) != Nfld)

		error("can't tokenize /dev/screen header");

	snprint(newcmd, sizeof newcmd, "-r %s %s %d %d",

		flds[1], flds[2], atoi(flds[3]) - 1, atoi(flds[4]) - 1);

	newwindow(newcmd);

	if (initdraw(nil, nil, "screenlock") < 0)

		sysfatal("initdraw failed");

	if(display == nil)

		error("no display");

	/* screen is now open and covered.  grab mouse and hold on tight */

	procrfork(grabmouse, nil, 4096, RFFDG);

	procrfork(blanker, nil, 4096, RFFDG);

	fd = open(pic, OREAD);

	if(fd > 0){

		i = readimage(display, fd, 0);

		if(i){

 			r = screen->r;

			p = Pt(r.max.x / 2, r.max.y * 2 / 3); 

			dx = (Dx(screen->r) - Dx(i->r)) / 2;

			r.min.x += dx;

			r.max.x -= dx;

			dy = (Dy(screen->r) - Dy(i->r)) / 2;

			r.min.y += dy;

			r.max.y -= dy;

			draw(screen, screen->r, display->black, nil, ZP);

			draw(screen, r, i, nil, i->r.min);

			flushimage(display, 1);

		}

		close(fd);

		/* identify the user on screen, centered */

		tm = localtime(time(0));

		s = smprint("user %s at %d:%02.2d", getuser(), tm->hour, tm->min);

		p = subpt(p, Pt(stringwidth(font, "m") * strlen(s) / 2, 0));

		screenstring(p, s);

	}

	/* clear the cursor */

	fd = open("/dev/cursor", OWRITE);

	if(fd > 0){

		memset(cbuf, 0, sizeof cbuf);

		write(fd, cbuf, sizeof cbuf);

		/* leave it open */

	}

}

void

threadmain(int argc, char *argv[])

{

	readfile("#c/user", user, sizeof user, 1);

	if((vgactl = open("/dev/vgactl", OWRITE)) < 0)

		vgactl = open("#v/vgactl", OWRITE);

	ARGBEGIN{

	case 'd':

		debug++;

		break;

	default:

		usage();

	}ARGEND

	if(argc != 0)

		usage();

	doblank = 1;

	lockscreen();

	checkpassword();

	threadexitsall(nil);

}