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         char *p, *server;
  57
  58         if(keypattern == nil)
  59                 keypattern = "";
  60         auth = vncrdlong(v);
  61         switch(auth){
  62         default:
  63                 werrstr("unknown auth type 0x%lux", auth);
  64                 if(verbose)
  65                         fprint(2, "unknown auth type 0x%lux\n", auth);
  66                 return -1;
  67
  68         case AFailed:
  69                 reason = vncrdstring(v);
  70                 werrstr("%s", reason);
  71                 if(verbose)
  72                         fprint(2, "auth failed: %s\n", reason);
  73                 return -1;
  74
  75         case ANoAuth:
  76                 if(verbose)
  77                         fprint(2, "no auth needed\n");
  78                 break;
  79
  80         case AVncAuth:
  81                 vncrdbytes(v, chal, VncChalLen);
  82                 server = strdup(serveraddr);
  83                 p = strrchr(server, ':');
  84                 if(p)
  85                         *p = 0;
  86                 if(auth_respond(chal, VncChalLen, nil, 0, chal, VncChalLen, auth_getkey,
  87                         "proto=vnc role=client server=%s %s", server, keypattern) != VncChalLen){
  88                         free(server);
  89                         return -1;
  90                 }
  91                 free(server);
  92                 vncwrbytes(v, chal, VncChalLen);
  93                 vncflush(v);
  94
  95                 auth = vncrdlong(v);
  96                 switch(auth){
  97                 default:
  98                         werrstr("unknown server response 0x%lux", auth);
  99                         return -1;
 100                 case VncAuthFailed:
 101                         werrstr("server says authentication failed");
 102                         return -1;
 103                 case VncAuthTooMany:
 104                         werrstr("server says too many tries");
 105                         return -1;
 106                 case VncAuthOK:
 107                         break;
 108                 }
 109                 break;
 110         }
 111         return 0;
 112 }
 113
 114 int
 115 vncsrvauth(Vnc *v)
 116 {
 117         Chalstate *c;
 118         AuthInfo *ai;
 119
 120         if((c = auth_challenge("proto=vnc role=server user=%q", getuser()))==nil)
 121                 sysfatal("vncchal: %r");
 122         if(c->nchal != VncChalLen)
 123                 sysfatal("vncchal got %d bytes wanted %d", c->nchal, VncChalLen);
 124         vncwrlong(v, AVncAuth);
 125         vncwrbytes(v, c->chal, VncChalLen);
 126         vncflush(v);
 127
 128         vncrdbytes(v, c->chal, VncChalLen);
 129         c->resp = c->chal;
 130         c->nresp = VncChalLen;
 131         ai = auth_response(c);
 132         auth_freechal(c);
 133         if(ai == nil){
 134                 fprint(2, "vnc auth failed: server factotum: %r\n");
 135                 vncwrlong(v, VncAuthFailed);
 136                 vncflush(v);
 137                 return -1;
 138         }
 139         auth_freeAI(ai);
 140         vncwrlong(v, VncAuthOK);
 141         vncflush(v);
 142
 143         return 0;
 144 }
 145