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