sys/src/cmd/vnc/auth.c

   1 #include "vnc.h"
   2 #include <libsec.h>
   3 #include <auth.h>
   4
   5 char *serveraddr;
   6
   7 enum
   8 {
   9         VerLen  = 12
  10 };
  11
  12 static char version[VerLen+1] = "RFB 003.003\n";
  13
  14 int
  15 vncsrvhandshake(Vnc *v)
  16 {
  17         char msg[VerLen+1];
  18
  19         strecpy(msg, msg+sizeof msg, version);
  20         if(verbose)
  21                 fprint(2, "server version: %s\n", msg);
  22         vncwrbytes(v, msg, VerLen);
  23         vncflush(v);
  24
  25         vncrdbytes(v, msg, VerLen);
  26         if(verbose)
  27                 fprint(2, "client version: %s\n", msg);
  28         return 0;
  29 }
  30
  31 int
  32 vnchandshake(Vnc *v)
  33 {
  34         char msg[VerLen+1];
  35
  36         msg[VerLen] = 0;
  37         vncrdbytes(v, msg, VerLen);
  38         if(strncmp(msg, "RFB ", 4) != 0){
  39                 werrstr("bad rfb version \"%s\"", msg);
  40                 return -1;
  41         }
  42         if(verbose)
  43                 fprint(2, "server version: %s\n", msg);
  44         strcpy(msg, version);
  45         vncwrbytes(v, msg, VerLen);
  46         vncflush(v);
  47         return 0;
  48 }
  49
  50 int
  51 vncauth(Vnc *v, char *keypattern)
  52 {
  53         char *reason;
  54         uchar chal[VncChalLen];
  55         ulong auth;
  56
  57         if(keypattern == nil)
  58                 keypattern = "";
  59         auth = vncrdlong(v);
  60         switch(auth){
  61         default:
  62                 werrstr("unknown auth type 0x%lux", auth);
  63                 if(verbose)
  64                         fprint(2, "unknown auth type 0x%lux\n", auth);
  65                 return -1;
  66
  67         case AFailed:
  68                 reason = vncrdstring(v);
  69                 werrstr("%s", reason);
  70                 if(verbose)
  71                         fprint(2, "auth failed: %s\n", reason);
  72                 return -1;
  73
  74         case ANoAuth:
  75                 if(verbose)
  76                         fprint(2, "no auth needed\n");
  77                 break;
  78
  79         case AVncAuth:
  80                 vncrdbytes(v, chal, VncChalLen);
  81                 if(auth_respond(chal, VncChalLen, nil, 0, chal, VncChalLen, auth_getkey,
  82                         "proto=vnc role=client server=%s %s", serveraddr, keypattern) != VncChalLen){
  83                         return -1;
  84                 }
  85                 vncwrbytes(v, chal, VncChalLen);
  86                 vncflush(v);
  87
  88                 auth = vncrdlong(v);
  89                 switch(auth){
  90                 default:
  91                         werrstr("unknown server response 0x%lux", auth);
  92                         return -1;
  93                 case VncAuthFailed:
  94                         werrstr("server says authentication failed");
  95                         return -1;
  96                 case VncAuthTooMany:
  97                         werrstr("server says too many tries");
  98                         return -1;
  99                 case VncAuthOK:
 100                         break;
 101                 }
 102                 break;
 103         }
 104         return 0;
 105 }
 106
 107 int
 108 vncsrvauth(Vnc *v)
 109 {
 110         Chalstate *c;
 111         AuthInfo *ai;
 112
 113         if((c = auth_challenge("proto=vnc role=server user=%q", getuser()))==nil)
 114                 sysfatal("vncchal: %r");
 115         if(c->nchal != VncChalLen)
 116                 sysfatal("vncchal got %d bytes wanted %d", c->nchal, VncChalLen);
 117         vncwrlong(v, AVncAuth);
 118         vncwrbytes(v, c->chal, VncChalLen);
 119         vncflush(v);
 120
 121         vncrdbytes(v, c->chal, VncChalLen);
 122         c->resp = c->chal;
 123         c->nresp = VncChalLen;
 124         ai = auth_response(c);
 125         auth_freechal(c);
 126         if(ai == nil){
 127                 fprint(2, "vnc auth failed: server factotum: %r\n");
 128                 vncwrlong(v, VncAuthFailed);
 129                 vncflush(v);
 130                 return -1;
 131         }
 132         auth_freeAI(ai);
 133         vncwrlong(v, VncAuthOK);
 134         vncflush(v);
 135
 136         return 0;
 137 }
 138