void AdafruitMQTT::randomClientID(char* clientid)
{
// length is from 10 to 23
uint8_t length = 10+(rng_u32()%13);
rng_base64(clientid, length);
clientid[length] = 0;
}
void AdafruitTwitter::generate_oauth_authorization(char authorization[], const char* http_method, const char* json_api,
char const* contents_para[][2], uint8_t contents_count)
{
//------------- Generate Oauth nonce & timestamp -------------//
// Generate Auth nonce
char nonce[32+1];
rng_base64(nonce, 32);
nonce[32] = 0;
// Timestamp (UTC)
char timestamp[32];
sprintf(timestamp, "%u", Feather.getUtcTime());
#if TWITTER_DEBUG // test code
strcpy(timestamp, "1469790936");
strcpy(nonce, "9b936321c0aaeab59e47fdc04934baa7");
#endif
//------------- OAUTH parameter & Data contents -------------//
// OAUTH parameters: ASSUME key and values are already in urlencoded
char const* oauth_para[][2] =
{
{ "oauth_consumer_key" , _consumer_key },
{ "oauth_nonce" , nonce },
{ "oauth_signature" , NULL },
{ "oauth_signature_method" , "HMAC-SHA1" },
{ "oauth_timestamp" , timestamp },
{ "oauth_token" , _token_access },
{ "oauth_version" , "1.0" },
};
uint8_t oauth_count = sizeof(oauth_para) / sizeof(oauth_para[0]);
//------------- Create Signature with HMAC SHA1 -------------//
char signature[TWITTER_OAUTH_SIGNATURE_MAXLEN];
create_oauth_signature(signature, http_method, json_api, oauth_para, oauth_count, contents_para, contents_count);
// Update OAUTH table
oauth_para[2][1] = signature;
//------------- Construct Authorization header -------------//
// format: key1="value1", key2="value2" ...
authorization += sprintf(authorization, "OAuth ");
for(uint8_t i=0; i<oauth_count; i++)
{
char const* key = oauth_para[i][0];
char const* value = oauth_para[i][1];
if (i != 0 )
{
*authorization++ = ',';
*authorization++ = ' ';
}
authorization += sprintf(authorization, "%s=\"%s\"", key, value);
}
}
