static void Password(const char *pass, const char *key) {
size_t keylen = strlen(key);
size_t passlen = strlen(pass);
// Create a new key, which is the XOR of the "key" and the challenge that
// was received from the server. If the vectors are of unequal length,
// the end is padded with values from the longest.
size_t newLength = keylen;
if (gLoginChallenge.size() > newLength)
newLength = gLoginChallenge.size();
unsigned char newkey[newLength];
for (size_t i=0; i<newLength; i++) newkey[i] = 0;
for (size_t i=0; i<keylen; i++) newkey[i] = key[i];
for (size_t i=0; i<gLoginChallenge.size(); i++) newkey[i] ^= gLoginChallenge[i];
#if 0
printf("Password: Key (len %d): ", newLength);
for (int i=0; i<newLength; i++) printf("%d ", newkey[i]);
printf("\n");
#endif
unsigned char b[passlen+3];
// Build the message into 'b'.
b[0] = passlen+3; // LSB of message length
b[1] = 0; // MSB of message length
b[2] = CMD_RESP_PASSWORD;
memcpy(b+3, pass, passlen); // Initialize with the clear text password
rc4_init(newkey, newLength);
rc4_xor(b+3, passlen); // Encrypt the password
#if 0
printf("encr: ");
for (int i=0; i<passlen; i++) printf(" %d", b[i+3]);
printf("\n");
#endif
SendMsg(b, passlen+3);
}
void rc4_test() {
// Test of encryption, according to http://en.wikipedia.org/wiki/RC4#Test_vectors
unsigned char buff[100];
strcpy((char *)buff, "Plaintext");
int l1 = strlen((char *)buff);
rc4_init((const unsigned char*)"Key", 3);
rc4_xor(buff, l1);
printf("rc4_test: ");
for (int i=0; i<l1; i++)
printf("%d ", buff[i]);
printf("\n");
}