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Diff for /src/usr.bin/ssh/packet.c between version 1.61.2.2 and 1.61.2.3

version 1.61.2.2, 2001/11/15 00:15:19 version 1.61.2.3, 2001/11/15 22:51:15
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 /* Session key information for Encryption and MAC */  /* Session key information for Encryption and MAC */
 Newkeys *newkeys[MODE_MAX];  Newkeys *newkeys[MODE_MAX];
   
   /* roundup current message to extra_pad bytes */
   static u_char extra_pad = 0;
   
 /*  /*
  * Sets the descriptors used for communication.  Disables encryption until   * Sets the descriptors used for communication.  Disables encryption until
  * packet_set_encryption_key is called.   * packet_set_encryption_key is called.
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 {  {
         static u_int32_t seqnr = 0;          static u_int32_t seqnr = 0;
         u_char type, *ucp, *macbuf = NULL;          u_char type, *ucp, *macbuf = NULL;
           u_char padlen, pad;
         char *cp;          char *cp;
         u_int packet_length = 0;          u_int packet_length = 0;
         u_int i, padlen, len;          u_int i, len;
         u_int32_t rand = 0;          u_int32_t rand = 0;
         Enc *enc   = NULL;          Enc *enc   = NULL;
         Mac *mac   = NULL;          Mac *mac   = NULL;
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         padlen = block_size - (len % block_size);          padlen = block_size - (len % block_size);
         if (padlen < 4)          if (padlen < 4)
                 padlen += block_size;                  padlen += block_size;
           if (extra_pad) {
                   /* will wrap if extra_pad+padlen > 255 */
                   extra_pad  = roundup(extra_pad, block_size);
                   pad = extra_pad - ((len + padlen) % extra_pad);
                   debug("packet_send2: adding %d (len %d padlen %d extra_pad %d)",
                       pad, len, padlen, extra_pad);
                   padlen += pad;
                   extra_pad = 0;
           }
         buffer_append_space(&outgoing_packet, &cp, padlen);          buffer_append_space(&outgoing_packet, &cp, padlen);
         if (enc && enc->cipher->number != SSH_CIPHER_NONE) {          if (enc && enc->cipher->number != SSH_CIPHER_NONE) {
                 /* random padding */                  /* random padding */
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         return s;          return s;
 }  }
   
   /* roundup current message to pad bytes */
   void
   packet_add_padding(u_char pad)
   {
           extra_pad = pad;
   }
   
 /*  /*
  * 9.2.  Ignored Data Message   * 9.2.  Ignored Data Message
  *   *
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  * required to send them. This message can be used as an additional   * required to send them. This message can be used as an additional
  * protection measure against advanced traffic analysis techniques.   * protection measure against advanced traffic analysis techniques.
  */   */
 /* size of current + ignore message should be n*sumlen bytes (w/o mac) */  
 void  
 packet_inject_ignore(int sumlen)  
 {  
         int blocksize, padlen, have, need, nb, mini, nbytes;  
         Enc *enc = NULL;  
   
         if (compat20 == 0)  
                 return;  
   
         have = buffer_len(&outgoing_packet);  
         debug2("packet_inject_ignore: current %d", have);  
         if (newkeys[MODE_OUT] != NULL)  
                 enc  = &newkeys[MODE_OUT]->enc;  
         blocksize = enc ? enc->cipher->block_size : 8;  
         padlen = blocksize - (have % blocksize);  
         if (padlen < 4)  
                 padlen += blocksize;  
         have += padlen;  
         have /= blocksize;      /* # of blocks for current message */  
   
         nb   = roundup(sumlen,  blocksize) / blocksize; /* blocks for both */  
         mini = roundup(5+1+4+4, blocksize) / blocksize; /* minsize ignore msg */  
         need = nb - (have % nb);                        /* blocks for ignore */  
         if (need <= mini)  
                 need += nb;  
         nbytes = (need - mini) * blocksize;     /* size of ignore payload */  
         debug2("packet_inject_ignore: block %d have %d nb %d mini %d need %d",  
             blocksize, have, nb, mini, need);  
   
         /* enqueue current message and append a ignore message */  
         packet_send();  
         packet_send_ignore(nbytes);  
 }  
   
 void  void
 packet_send_ignore(int nbytes)  packet_send_ignore(int nbytes)
 {  {
Legend:
Removed from v.1.61.2.2  
changed lines
  Added in v.1.61.2.3