//Sending the TURN message to the network.
void turn_send(int8_t rotation){
uint8_t data;
xQueueSend(turnQueue, ( void * )&rotation, 0); // put the rotation into the queue
data = (uint8_t) rotation;
send_new_packet(TURN, &data, EVERYBODY); // tell to the neighbors that the block turned
addDirection(( 4 - rotation));
}
//Send PONG in order to answer a PING message.
void pong_task(void *parameters){
Packet packet;
uint8_t data[2];
while(1){
xQueueReceive(xPongQueue, &packet, portMAX_DELAY);
data[0] = getMembersInNetwork();
data[1] = packet.interface;
if(sendPing == 1)
send_new_packet(PONG,data, packet.interface);
}
}
/* this actually makes the message block and sends it */
int
build_message (FILE * in_ptr, byte numdest,
char **destination, int *chain, byte numsub,
char **subject, char *outfile, int outfileflag,
REMAILER * remailer_list, int num_remailers,
int client)
{
int hop, i, j, k, numpackets, packet, copy;
long int chunk, tmpchunk;
byte iv[8];
byte ivarray[NUM_IV][8], innerkey[24], digest[16];
BUFFER *sendbuff, *bodybuff, *headbuff[21], *message, *tempbuff;
long offset;
char line[1024];
byte *key[5], packetID[16], commonpacketID[16], messageID[16];
byte tmpbyte;
byte packet_type;
#ifdef USE_RSAREF
PUBLIC_KEY pubKey, *keyPtr[5];
unsigned int numPubKeys, keylen;
R_ENVELOPE_CTX rsa_context;
#else
PUBLIC_KEY pubKey;
unsigned int keylen;
B_ALGORITHM_OBJ rsa_context;
B_ALGORITHM_OBJ des_context;
B_KEY_OBJ des_key;
#endif
unsigned long timestamp;
message = new_buffer ();
/* prepend destinations to body */
add_to_buffer (message, &numdest, 1);
for (i = 0; i < numdest; i++)
add_to_buffer (message, destination[i], DESTSIZE);
/* add message header lines to body */
add_to_buffer (message, &numsub, 1);
for (i = 0; i < numsub; i++)
add_to_buffer (message, subject[i], SUBSIZE);
offset = message->length;
/* add the file to body */
if (in_ptr)
{
while ((i = fread (line, 1, sizeof (line), in_ptr)) > 0)
{
if (i < 0)
return (-1); /* file error */
add_to_buffer (message, line, i);
}
fclose (in_ptr);
}
/* message is complete. */
add_to_random (message->message, message->length);
/* Choose the final hop now. */
if (chain[chain[0]] == 0)
if (rnd_select (chain[0], chain, remailer_list, num_remailers) < 0)
return (-1);
#ifdef USE_ZLIB
/* should we compress this message? */
if (message->length > PACKETSIZE &&
check_abilities (remailer_list[chain[chain[0]]].abilities, "C", ""))
{
tempbuff = new_buffer ();
if (compress_buf2buf (message, tempbuff, offset))
{
free_buffer (message);
message = tempbuff;
}
else
free_buffer (tempbuff);
}
/* in case it already is compressed, but should not be */
if (!check_abilities (remailer_list[chain[chain[0]]].abilities, "C", ""))
{
tempbuff = new_buffer ();
if (uncompress_buf2buf (message, tempbuff, offset))
{
free_buffer (message);
message = tempbuff;
}
else
free_buffer (tempbuff);
}
#endif
numpackets = message->length / PACKETSIZE;
if (message->length % PACKETSIZE != 0)
numpackets++;
bodybuff = new_buffer ();
sendbuff = new_buffer ();
for (i = 1; i <= HOPMAX; i++)
headbuff[i] = new_buffer ();
our_randombytes (messageID, 16);
/* Loop to make one packet at a time */
for (packet = 1; packet <= numpackets; packet++)
{
/* put the packet in bodybuff, and put the rest back in message */
chunk = message->length;
if (chunk > PACKETSIZE)
chunk = PACKETSIZE;
clear_buffer (bodybuff);
tmpchunk = chunk;
tmpbyte = tmpchunk & 0xFF;
add_to_buffer (bodybuff, &tmpbyte, 1); /* prepend length of data low byte */
tmpchunk = tmpchunk / 256;
tmpbyte = tmpchunk & 0xFF;
add_to_buffer (bodybuff, &tmpbyte, 1); /* prepend length of data 2nd byte */
tmpchunk = tmpchunk / 256;
tmpbyte = tmpchunk & 0xFF;
add_to_buffer (bodybuff, &tmpbyte, 1); /* prepend length of data 3rd byte */
tmpchunk = tmpchunk / 256;
tmpbyte = tmpchunk & 0xFF;
add_to_buffer (bodybuff, &tmpbyte, 1); /* prepend length of data high byte */
add_to_buffer (bodybuff, message->message, chunk);
tempbuff = new_buffer ();
add_to_buffer (tempbuff, (message->message) + chunk, message->length - chunk);
free_buffer (message);
message = tempbuff;
if (NUMCOPIES < 1 || NUMCOPIES > 10)
{
fprintf (errlog, "Error: Invalid number of copies.\n");
return (-1);
}
for (copy = 1; copy <= NUMCOPIES; copy++)
{
clear_buffer (sendbuff);
add_to_buffer (sendbuff, bodybuff->message, bodybuff->length);
pad_buffer (sendbuff, PACKETSIZE + 4);
/* Create fake header cards */
for (i = chain[0] + 1; i <= HOPMAX; i++)
{
reset_buffer (headbuff[i]);
pad_buffer (headbuff[i], HEADERSIZE);
}
if (rnd_selectchain (chain, remailer_list, num_remailers) < 0)
return (-1);
for (hop = chain[0]; hop >= 1; hop--)
{
/* Get public key for remailer */
if (get_pub_key (remailer_list[abs (chain[hop])].key_ID,
&pubKey) != 0)
{
fprintf (errlog, "Can't get public key!\n");
return (-1);
}
key[0] = malloc (MAX_ENCRYPTED_KEY_LEN);
#ifdef USE_RSAREF
numPubKeys = 1;
keyPtr[0] = &pubKey;
if (R_SealInit (&rsa_context, key, &keylen, iv, numPubKeys,
keyPtr, EA_DES_EDE3_CBC, &random_obj) != 0)
{
fprintf (errlog, "R_SealInit error %x!!!\n", i);
exit (-1);
}
#else
B_CreateAlgorithmObject (&rsa_context);
B_CreateAlgorithmObject (&des_context);
B_SetAlgorithmInfo (rsa_context, AI_PKCS_RSAPublic, 0);
B_SetAlgorithmInfo (des_context, AI_DES_EDE3_CBC_IV8, iv);
our_randombytes (line, 24);
B_CreateKeyObject (&des_key);
B_SetKeyInfo (des_key, KI_DES24Strong, line);
B_EncryptInit (rsa_context, pubKey, CHOOSER, NULL);
B_EncryptUpdate (rsa_context, key[0], &keylen,
MAX_ENCRYPTED_KEY_LEN, line, 24,
random_obj, NULL);
B_EncryptFinal (rsa_context, key[0] + keylen, &k,
MAX_ENCRYPTED_KEY_LEN - keylen, random_obj,
NULL);
B_DestroyAlgorithmObject (&rsa_context);
B_DestroyKeyObject (&pubKey);
keylen += k;
B_EncryptInit (des_context, des_key, CHOOSER, NULL);
/* XXX Error handling! */
#endif
/* make packet ID and innerkey */
/* packet ID is unique except for duplicates in the last hop */
if (hop != chain[0])
our_randombytes (packetID, 16);
else
{
if (copy == 1)
our_randombytes (commonpacketID, 16);
memcpy (packetID, commonpacketID, 16);
}
our_randombytes (innerkey, 24);
/* make the iv array */
for (i = 0; i < NUM_IV; i++)
our_randombytes (ivarray[i], 8);
/* Now build the current header */
reset_buffer (headbuff[hop]);
add_to_buffer (headbuff[hop], packetID, 16); /* also like another IV */
add_to_buffer (headbuff[hop], innerkey, 24); /* Key used to encrypt headers and body */
if (hop == chain[0])
{ /* if this is the last hop */
if (numpackets == 1)
/* final hop */
packet_type = P_FINAL;
else
/* partial message */
packet_type = P_PARTIAL;
add_to_buffer (headbuff[hop], &packet_type, 1);
if (packet_type & P_PARTIAL)
{
tmpbyte = packet; /* which packet is this */
add_to_buffer (headbuff[hop], &tmpbyte, 1);
tmpbyte = numpackets; /* out of how many */
add_to_buffer (headbuff[hop], &tmpbyte, 1);
}
add_to_buffer (headbuff[hop], messageID, 16);
add_to_buffer (headbuff[hop], ivarray[BODY_IV], 8);
}
else
{ /* this is not the last hop */
packet_type = 0; /* packet type = intermediate packet */
add_to_buffer (headbuff[hop], &packet_type, 1);
/* insert the array of IVs */
for (i = 0; i < NUM_IV; i++)
{
add_to_buffer (headbuff[hop], ivarray[i], 8);
}
add_to_buffer (headbuff[hop], remailer_list[abs (chain[hop + 1])].name, 80);
}
/* Extension to original mixmaster format:
Use timestamp to prevent replay of old messages. */
add_to_buffer (headbuff[hop], TSMAGIC, sizeof(TSMAGIC));
/* Fuzzy timestamp: don't leak more information than necessary */
timestamp = time(NULL) / SECONDSPERDAY - random_number(4);
tmpbyte = timestamp & 0xFF;
add_to_buffer (headbuff[hop], &tmpbyte, 1);
tmpbyte = (timestamp / 256) & 0xFF;
add_to_buffer (headbuff[hop], &tmpbyte, 1);
/* Make and append an MD5 checksum of the packet */
make_digest (headbuff[hop], digest);
add_to_buffer (headbuff[hop], digest, 16);
/* Now pad pre-encrypted header to standard size */
pad_buffer (headbuff[hop], INNERHEAD);
/* Done building headbuff[hop] so now RSA it */
tempbuff = new_buffer ();
assert (headbuff[hop]->length <= INNERHEAD);
#ifdef USE_RSAREF
R_SealUpdate (&rsa_context, line, &k, headbuff[hop]->message,
headbuff[hop]->length);
#else
B_EncryptUpdate (des_context, line, &k, sizeof (line),
headbuff[hop]->message, headbuff[hop]->length,
random_obj, NULL);
#endif
add_to_buffer (tempbuff, line, k);
#ifdef USE_RSAREF
R_SealFinal (&rsa_context, line, &k);
#else
B_EncryptFinal (des_context, line, &k,
INNERHEAD - k,
random_obj, NULL);
B_DestroyAlgorithmObject (&des_context);
B_DestroyKeyObject (&des_key);
#endif
add_to_buffer (tempbuff, line, k);
clear_buffer (headbuff[hop]);
/* Prepend RSA key ID */
add_to_buffer (headbuff[hop], remailer_list[abs (chain[hop])].key_ID, 16);
/* prepend keys and IV to header */
tmpbyte = keylen;
add_to_buffer (headbuff[hop], &tmpbyte, 1);
add_to_buffer (headbuff[hop], key[0], tmpbyte);
add_to_buffer (headbuff[hop], iv, 8);
/* add encryped header */
add_to_buffer (headbuff[hop], tempbuff->message, tempbuff->length);
free_buffer (tempbuff);
/* pad out encrypted header to standard size */
pad_buffer (headbuff[hop], HEADERSIZE);
/* encrypt body */
crypt_in_buffer (innerkey, ivarray[BODY_IV], sendbuff, 1);
/* encrypt all later headers */
/* i is the index for ivarray */
for (i = 0, j = hop + 1; j <= HOPMAX; j++)
crypt_in_buffer (innerkey, ivarray[i++], headbuff[j], 1);
} /* hop loop for a given packet */
if (VERBOSE)
{
fprintf (errlog, "Packet chain: ");
for (i = 1; i <= chain[0]; i++)
fprintf (errlog, "%s;", remailer_list[abs (chain[i])].shortname);
fprintf (errlog, "\n");
}
if (strlen (outfile) > 0 && (!streq (outfile, "-")) && (numpackets > 1 || NUMCOPIES > 1))
{
sprintf (line, "%s.%d", outfile, (packet - 1) * NUMCOPIES + copy);
send_new_packet (headbuff, sendbuff, remailer_list[abs (chain[1])].name, line, outfileflag, client);
}
else
{
send_new_packet (headbuff, sendbuff, remailer_list[abs (chain[1])].name, outfile, outfileflag, client);
}
} /* copies of one packet */
} /* end loop processing packets */
free_buffer (bodybuff);
free_buffer (sendbuff);
free_buffer (message);
for (i = 1; i <= HOPMAX; i++)
free_buffer (headbuff[i]);
return (0);
}
