sys/src/cmd/screenlock.c

   1 /* screenlock - lock a terminal */
   2 #include <u.h>
   3 #include <libc.h>
   4 #include <libsec.h>
   5 #include <draw.h>
   6 #include <thread.h>
   7 #include <auth.h>
   8
   9 char pic[] = "/lib/bunny.bit";
  10 int debug;
  11 long blank;
  12
  13 void
  14 usage(void)
  15 {
  16         fprint(2, "usage: %s [-d]\n", argv0);
  17         exits("usage");
  18 }
  19
  20 /* ^D, Delete, Enter, Backspace, ^U */
  21 void
  22 readline(char *buf, int nbuf)
  23 {
  24         char c;
  25         int i;
  26
  27         i = 0;
  28         while(i < nbuf-1){
  29                 if(read(0, &c, 1) != 1 || c == '\04' || c == '\177'){
  30                         i = 0;
  31                         break;
  32                 } else if(c == '\n')
  33                         break;
  34                 else if(c == '\b' && i > 0)
  35                         --i;
  36                 else if(c == ('u' & 037))
  37                         i = 0;
  38                 else
  39                         buf[i++] = c;
  40                 blank = time(0);
  41         }
  42         buf[i] = '\0';
  43 }
  44
  45 void
  46 checkpassword(void)
  47 {
  48         char buf[256];
  49         AuthInfo *ai;
  50
  51         for(;;){
  52                 memset(buf, 0, sizeof buf);
  53                 readline(buf, sizeof buf);
  54
  55                 border(screen, screen->r, 8, display->white, ZP);
  56                 flushimage(display, 1);
  57
  58                 /* authenticate */
  59                 ai = auth_userpasswd(getuser(), buf);
  60                 if(ai != nil && ai->cap != nil)
  61                         break;
  62
  63                 rerrstr(buf, sizeof buf);
  64                 if(strncmp(buf, "needkey ", 8) == 0)
  65                         break;
  66
  67                 auth_freeAI(ai);
  68                 border(screen, screen->r, 8, display->black, ZP);
  69                 flushimage(display, 1);
  70         }
  71         auth_freeAI(ai);
  72         memset(buf, 0, sizeof buf);
  73 }
  74
  75 void
  76 blanker(void *)
  77 {
  78         int fd;
  79
  80         if((fd = open("/dev/mousectl", OWRITE)) < 0)
  81                 return;
  82
  83         for(;;){
  84                 if(blank != 0 && ((ulong)time(0) - (ulong)blank) >= 5){
  85                         blank = 0;
  86                         write(fd, "blank", 5);
  87                 }
  88                 sleep(1000);
  89         }
  90 }
  91
  92 void
  93 grabmouse(void*)
  94 {
  95         int fd, x, y;
  96         char ibuf[256], obuf[256];
  97
  98         if((fd = open("/dev/mouse", ORDWR)) < 0)
  99                 sysfatal("can't open /dev/mouse: %r");
 100
 101         snprint(obuf, sizeof obuf, "m %d %d",
 102                 screen->r.min.x + Dx(screen->r)/2,
 103                 screen->r.min.y + Dy(screen->r)/2);
 104
 105         while(read(fd, ibuf, sizeof ibuf) > 0){
 106                 ibuf[12] = 0;
 107                 ibuf[24] = 0;
 108                 x = atoi(ibuf+1);
 109                 y = atoi(ibuf+13);
 110                 if(x != screen->r.min.x + Dx(screen->r)/2 ||
 111                    y != screen->r.min.y + Dy(screen->r)/2){
 112                         if(!debug)
 113                                 fprint(fd, "%s", obuf);
 114                         blank = time(0);
 115                 }
 116         }
 117 }
 118
 119 void
 120 top(void*)
 121 {
 122         int fd;
 123
 124         if((fd = open("/dev/wctl", OWRITE)) < 0)
 125                 return;
 126
 127         for(;;){
 128                 write(fd, "current", 7);
 129                 sleep(500);
 130         }
 131 }
 132
 133 void
 134 lockscreen(void)
 135 {
 136         enum { Cursorlen = 2*4 + 2*2*16 };
 137         char *s;
 138         char newcmd[128], cbuf[Cursorlen];
 139         int fd, dx, dy;
 140         Image *i;
 141         Point p;
 142         Rectangle r;
 143         Tm *tm;
 144
 145         display = initdisplay(nil, nil, nil);
 146         if(display == nil)
 147                 sysfatal("can't open /dev/draw: %r");
 148         r = display->image->r;
 149         snprint(newcmd, sizeof newcmd, "-r %d %d %d %d",
 150                 r.min.x, r.min.y, r.max.x, r.max.y);
 151         closedisplay(display);
 152
 153         newwindow(newcmd);
 154         if((fd = open("/dev/consctl", OWRITE)) >= 0)
 155                 write(fd, "rawon", 5);
 156
 157         if((fd = open("/dev/cons", OREAD)) < 0)
 158                 sysfatal("can't open cons: %r");
 159         dup(fd, 0);
 160
 161         if((fd = open("/dev/cons", OWRITE)) < 0)
 162                 sysfatal("can't open cons: %r");
 163         dup(fd, 1);
 164         dup(fd, 2);
 165
 166         if(initdraw(nil, nil, "screenlock") < 0)
 167                 sysfatal("initdraw failed");
 168         screen = _screen->image;        /* fullscreen */
 169
 170         if((fd = open(pic, OREAD)) >= 0){
 171                 if((i = readimage(display, fd, 0)) != nil){
 172                         r = screen->r;
 173                         p = Pt(r.max.x / 2, r.max.y * 2 / 3);
 174                         dx = (Dx(screen->r) - Dx(i->r)) / 2;
 175                         r.min.x += dx;
 176                         r.max.x -= dx;
 177                         dy = (Dy(screen->r) - Dy(i->r)) / 2;
 178                         r.min.y += dy;
 179                         r.max.y -= dy;
 180                         draw(screen, screen->r, display->black, nil, ZP);
 181                         draw(screen, r, i, nil, i->r.min);
 182                 }
 183                 close(fd);
 184
 185                 /* identify the user on screen, centered */
 186                 tm = localtime(time(&blank));
 187                 s = smprint("user %s at %d:%02.2d", getuser(), tm->hour, tm->min);
 188                 p = subpt(p, Pt(stringwidth(font, "m") * strlen(s) / 2, 0));
 189                 string(screen, p, screen->display->white, ZP, font, s);
 190         }
 191         flushimage(display, 1);
 192
 193         /* screen is now open and covered.  grab mouse and hold on tight */
 194         procrfork(top, nil, 8*1024, RFFDG);
 195         procrfork(grabmouse, nil, 8*1024, RFFDG);
 196         procrfork(blanker, nil, 8*1024, RFFDG);
 197
 198         /* clear the cursor */
 199         if((fd = open("/dev/cursor", OWRITE)) >= 0){
 200                 memset(cbuf, 0, sizeof cbuf);
 201                 write(fd, cbuf, sizeof cbuf);
 202                 /* leave it open */
 203         }
 204 }
 205
 206 void
 207 threadmain(int argc, char *argv[])
 208 {
 209         ARGBEGIN{
 210         case 'd':
 211                 debug++;
 212                 break;
 213         default:
 214                 usage();
 215         }ARGEND
 216
 217         if(argc != 0)
 218                 usage();
 219
 220         lockscreen();
 221         checkpassword();
 222         threadexitsall(nil);
 223 }