summaryrefslogtreecommitdiff
path: root/protocols/Twitter/src/oauth.cpp
blob: 2235ca88ce8d8fdbbf5df06e7869d4ef9fbe6005 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
/* aww whatup?  this is all the oauth functions, at the moment
 * they're all part of the twitter class.. i think this is the
 * best way?  
 */

#include "twitter.h"
//#include "tc2.h"
#include "utility.h"
#include "stdafx.h"
#include "common.h"

OAuthParameters mir_twitter::BuildSignedOAuthParameters( const OAuthParameters& requestParameters, 
								   const std::wstring& url, 
								   const std::wstring& httpMethod, 
								   const OAuthParameters *postData,
								   const std::wstring& consumerKey, 
								   const std::wstring& consumerSecret,
								   const std::wstring& requestToken = L"", 
								   const std::wstring& requestTokenSecret = L"", 
								   const std::wstring& pin = L"" )
{
	wstring timestamp = OAuthCreateTimestamp();
	wstring nonce = OAuthCreateNonce();

	// create oauth requestParameters
	OAuthParameters oauthParameters;

	oauthParameters[L"oauth_timestamp"] = timestamp;
	oauthParameters[L"oauth_nonce"] = nonce;
	oauthParameters[L"oauth_version"] = L"1.0";
	oauthParameters[L"oauth_signature_method"] = L"HMAC-SHA1";
	oauthParameters[L"oauth_consumer_key"] = consumerKey;

	// add the request token if found
	if (!requestToken.empty())
	{
		oauthParameters[L"oauth_token"] = requestToken; /*WLOG("requestToken not empty: %s", requestToken);*/
	}

	// add the authorization pin if found
	if (!pin.empty())
	{
		oauthParameters[L"oauth_verifier"] = pin;
	}

	// create a parameter list containing both oauth and original parameters
	// this will be used to create the parameter signature
	OAuthParameters allParameters = requestParameters;

	if(Compare(httpMethod, L"POST", false) && postData) {
		//LOG("in post section of buildOAuthParams");
		allParameters.insert(postData->begin(), postData->end());
	}

	allParameters.insert(oauthParameters.begin(), oauthParameters.end());

	// prepare a signature base, a carefully formatted string containing 
	// all of the necessary information needed to generate a valid signature
	wstring normalUrl = OAuthNormalizeUrl(url);
	//WLOG("normalURL is %s", normalUrl);
	wstring normalizedParameters = OAuthNormalizeRequestParameters(allParameters);
	//WLOG("normalisedparams is %s", normalizedParameters);
	wstring signatureBase = OAuthConcatenateRequestElements(httpMethod, normalUrl, normalizedParameters);
	//WLOG("sigBase is %s", signatureBase);

	// obtain a signature and add it to header requestParameters
	wstring signature = OAuthCreateSignature(signatureBase, consumerSecret, requestTokenSecret);
	//WLOG("**BuildSignedOAuthParameters - sig is %s", signature);
	oauthParameters[L"oauth_signature"] = signature;

	return oauthParameters;
}

wstring mir_twitter::UrlGetQuery( const wstring& url ) 
{
	wstring query;
	/*
	URL_COMPONENTS components = {sizeof(URL_COMPONENTS)};

	wchar_t buf[1024*4] = {};

	components.lpszExtraInfo = buf;
	components.dwExtraInfoLength = SIZEOF(buf);

	BOOL crackUrlOk = InternetCrackUrl(url.c_str(), url.size(), 0, &components);
	_ASSERTE(crackUrlOk);
	if(crackUrlOk)
	{*/

		map<wstring, wstring> brokenURL = CrackURL(url);

		query = brokenURL[L"extraInfo"];
		//WLOG("inside crack, url is %s", url);
		wstring::size_type q = query.find_first_of(L'?');
		if(q != wstring::npos)
		{
			query = query.substr(q + 1);
		}

		wstring::size_type h = query.find_first_of(L'#');
		if(h != wstring::npos)
		{
			query = query.substr(0, h);
		}
	//}
	return query;
}

// OAuthWebRequest used for all OAuth related queries
//
// consumerKey and consumerSecret - must be provided for every call, they identify the application
// oauthToken and oauthTokenSecret - need to be provided for every call, except for the first token request before authorizing
// pin - only used during authorization, when the user enters the PIN they received from the twitter website
wstring mir_twitter::OAuthWebRequestSubmit( 
    const wstring& url, 
    const wstring& httpMethod, 
	const OAuthParameters *postData,
    const wstring& consumerKey, 
    const wstring& consumerSecret, 
	const wstring& oauthToken, 
    const wstring& oauthTokenSecret, 
    const wstring& pin
    )
{
	//WLOG("URL is %s", url);
    wstring query = UrlGetQuery(url);
	//WLOG("query is %s", query);
    OAuthParameters originalParameters = ParseQueryString(query);

    OAuthParameters oauthSignedParameters = BuildSignedOAuthParameters(
        originalParameters, 
        url, 
        httpMethod, postData,
        consumerKey, consumerSecret, 
        oauthToken, oauthTokenSecret, 
        pin );
    return OAuthWebRequestSubmit(oauthSignedParameters, url);
}

wstring mir_twitter::OAuthWebRequestSubmit( 
	const OAuthParameters& parameters, 
	const wstring& url 
	) 
{
	//WLOG("OAuthWebRequestSubmit(%s)", url);

	//wstring oauthHeader = L"Authorization: OAuth ";
	wstring oauthHeader = L"OAuth ";

	for(OAuthParameters::const_iterator it = parameters.begin(); 
		it != parameters.end(); 
		++it)
	{
		//WLOG("%s = ", it->first);
		//WLOG("%s", it->second);
		//LOG("---------");

		if(it != parameters.begin())
		{
			oauthHeader += L",";
		}

		wstring pair;
		pair += it->first + L"=\"" + it->second + L"\"";
		oauthHeader += pair;
	}

	//WLOG("oauthheader is %s", oauthHeader);

	return oauthHeader;
}

// parameters must already be URL encoded before calling BuildQueryString
std::wstring mir_twitter::BuildQueryString( const OAuthParameters &parameters ) 
{
	wstring query;
	//LOG("do we ever get here?");
	for(OAuthParameters::const_iterator it = parameters.begin(); 
		it != parameters.end(); 
		++it)
	{
		//LOG("aww como ONNNNNN");
		//LOG("%s = %s", it->first.c_str(), it->second.c_str());
		//WLOG("in buildqueryString bit, first is %s", it->first);

		if(it != parameters.begin())
		{
			query += L"&";
		}

		wstring pair;
		pair += it->first + L"=" + it->second + L"";
		query += pair;
	}	
	return query;
}

wstring mir_twitter::OAuthConcatenateRequestElements( const wstring& httpMethod, wstring url, const wstring& parameters ) 
{
	wstring escapedUrl = UrlEncode(url);
	//WLOG("before OAUTHConcat, params are %s", parameters);
	wstring escapedParameters = UrlEncode(parameters);
	//LOG(")))))))))))))))))))))))))))))))))))))))))))))))");
	//WLOG("after url encode, its %s", escapedParameters);
	wstring ret = httpMethod + L"&" + escapedUrl + L"&" + escapedParameters;
	return ret;
}

/* CrackURL.. just basically pulls apart a url into a map of wstrings:
 * scheme, domain, port, path, extraInfo, explicitPort
 * explicitPort will be 0 or 1, 0 if there was no actual port in the url,
 * and 1 if it was explicitely specified.
 * eg "http://twitter.com/blah.htm" will give:
 * http, twitter.com, 80, blah.htm, "", 0
 * "https://twitter.com:989/blah.htm?boom" will give:
 * https, twitter.com, 989, blah.htm?boom, ?boom, 1
 */
map<wstring, wstring> mir_twitter::CrackURL(wstring url) {

	wstring scheme1, domain1, port1, path1, extraInfo, explicitPort;
	vector<wstring> urlToks, urlToks2, extraInfoToks;

	Split(url, urlToks, L':', false);
	//WLOG("**CRACK - URL to split is %s", url);

	scheme1 = urlToks[0];
	//WLOG("**CRACK - scheme is %s", scheme1);

	if (urlToks.size() == 2) { // if there is only 1 ":" in the url
		if (Compare(scheme1, L"http", false)) {
			port1 = L"80";
		}
		else {
			port1 = L"443";
		}

		//WLOG("**CRACK::2 - port is %s", port1);

		Split(urlToks[1], urlToks2, L'/', false);
		domain1 = urlToks2[0];
		//WLOG("**CRACK::2 - domain is %s", domain1);
		explicitPort = L"0";
	}
	else if (urlToks.size() == 3) { // if there are 2 ":"s in the URL, ie a port is explicitly set
		domain1 = urlToks[1].substr(2, urlToks[1].size());
		//WLOG("**CRACK::3 - domain is %s", domain1);
		Split(urlToks[2], urlToks2, L'/', false);
		port1 = urlToks2[0];
		//WLOG("**CRACK::3 - port is %s", port1);
		explicitPort = L"1";
	}
	else {
		WLOG("**CRACK - not a proper URL? doesn't have a colon. URL is %s", url);

	}

	for (size_t i = 1; i < urlToks2.size(); ++i) {
		if (i > 1) {
			path1 += L"/";
		}
		path1 += urlToks2[i];
	}
	//WLOG("**CRACK - path is %s", path1);
	
	wstring::size_type foundHash = path1.find(L"#");
	wstring::size_type foundQ = path1.find(L"?");

	if ((foundHash != wstring::npos) || (foundQ != wstring::npos)) { // if we've found a # or a ?...
		if (foundHash == wstring::npos) { // if we didn't find a #, we must have found a ?
			extraInfo = path1.substr(foundQ);
		}
		else if (foundQ == wstring::npos) { // if we didn't find a ?, we must have found a #
			extraInfo = path1.substr(foundHash);
		}
		else { // we found both a # and a ?, whichever came first we grab the sub string from there
			if (foundQ < foundHash) {
				extraInfo = path1.substr(foundQ);
			}
			else {
				extraInfo = path1.substr(foundHash);
			}
		}
	}
	else { // we have no # or ? in the path...
		extraInfo = L"";
	}

	//WLOG("**CRACK - extraInfo is %s", extraInfo);

	map<wstring, wstring> result;
	result[L"scheme"] = scheme1;
	result[L"domain"] = domain1;
	result[L"port"] = port1;
	result[L"path"] = path1;
	result[L"extraInfo"] = extraInfo;
	result[L"explicitPort"] = explicitPort;

	return result;
}

wstring mir_twitter::OAuthNormalizeUrl( const wstring& url ) 
{
	/*wchar_t scheme[1024*4] = {};
	wchar_t host[1024*4] = {};
	wchar_t path[1024*4] = {};

	URL_COMPONENTS components = { sizeof(URL_COMPONENTS) };

	components.lpszScheme = scheme;
	components.dwSchemeLength = SIZEOF(scheme);

	components.lpszHostName = host;
	components.dwHostNameLength = SIZEOF(host);

	components.lpszUrlPath = path;
	components.dwUrlPathLength = SIZEOF(path);

	BOOL crackUrlOk = InternetCrackUrl(url.c_str(), url.size(), 0, &components);*/

	wstring normalUrl = url;
	map<wstring, wstring> brokenURL = CrackURL(url);

	/*_ASSERTE(crackUrlOk);
	if(crackUrlOk)
	{*/
		wchar_t port[10] = {};

		// The port number must only be included if it is non-standard
		if(Compare(brokenURL[L"scheme"], L"http", false) && !(Compare(brokenURL[L"port"], L"80", false)) || 
			(Compare(brokenURL[L"scheme"], L"https", false) && !(Compare(brokenURL[L"port"], L"443", false))))
		{
			swprintf_s(port, SIZEOF(port), L":%s", brokenURL[L"port"]);
		}

		// InternetCrackUrl includes ? and # elements in the path, 
		// which we need to strip off
		wstring pathOnly = brokenURL[L"path"];
		wstring::size_type q = pathOnly.find_first_of(L"#?");
		if(q != wstring::npos)
		{
			pathOnly = pathOnly.substr(0, q);
		}

		normalUrl = brokenURL[L"scheme"] + L"://" + brokenURL[L"domain"] + port + L"/" + pathOnly;
		//WLOG("**OAuthNOrmailseURL - normalUrl is %s", normalUrl);
	//}
	return normalUrl;
}

wstring mir_twitter::OAuthNormalizeRequestParameters( const OAuthParameters& requestParameters ) 
{
	list<wstring> sorted;
	for(OAuthParameters::const_iterator it = requestParameters.begin(); 
		it != requestParameters.end(); 
		++it)
	{
		wstring param = it->first + L"=" + it->second;
		sorted.push_back(param);
	}
	sorted.sort();

	wstring params;
	for(list<wstring>::iterator it = sorted.begin(); it != sorted.end(); ++it)
	{
		if(params.size() > 0)
		{
			params += L"&";
		}
		params += *it;
	}

	return params;
}

OAuthParameters mir_twitter::ParseQueryString( const wstring& url ) 
{
	OAuthParameters ret;

	vector<wstring> queryParams;
	Split(url, queryParams, L'&', false);

	for(size_t i = 0; i < queryParams.size(); ++i)
	{
		vector<wstring> paramElements;
		Split(queryParams[i], paramElements, L'=', true);
		_ASSERTE(paramElements.size() == 2);
		if(paramElements.size() == 2)
		{
			ret[paramElements[0]] = paramElements[1];
		}
	}
	return ret;
}

wstring mir_twitter::OAuthCreateNonce() 
{
	wchar_t ALPHANUMERIC[] = L"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
	wstring nonce;

	for(int i = 0; i <= 16; ++i)
	{
		nonce += ALPHANUMERIC[rand() % (SIZEOF(ALPHANUMERIC) - 1)]; // don't count null terminator in array
	}
	return nonce;
}

wstring mir_twitter::OAuthCreateTimestamp() 
{
	__time64_t utcNow;
	__time64_t ret = _time64(&utcNow);
	_ASSERTE(ret != -1);

	wchar_t buf[100] = {};
	swprintf_s(buf, SIZEOF(buf), L"%I64u", utcNow);

	return buf;
}

string mir_twitter::HMACSHA1( const string& keyBytes, const string& data ) 
{
	// based on http://msdn.microsoft.com/en-us/library/aa382379%28v=VS.85%29.aspx

	string hash;

	//--------------------------------------------------------------------
	// Declare variables.
	//
	// hProv:           Handle to a cryptographic service provider (CSP). 
	//                  This example retrieves the default provider for  
	//                  the PROV_RSA_FULL provider type.  
	// hHash:           Handle to the hash object needed to create a hash.
	// hKey:            Handle to a symmetric key. This example creates a 
	//                  key for the RC4 algorithm.
	// hHmacHash:       Handle to an HMAC hash.
	// pbHash:          Pointer to the hash.
	// dwDataLen:       Length, in bytes, of the hash.
	// Data1:           Password string used to create a symmetric key.
	// Data2:           Message string to be hashed.
	// HmacInfo:        Instance of an HMAC_INFO structure that contains 
	//                  information about the HMAC hash.
	// 
	HCRYPTPROV  hProv       = NULL;
	HCRYPTHASH  hHash       = NULL;
	HCRYPTKEY   hKey        = NULL;
	HCRYPTHASH  hHmacHash   = NULL;
	PBYTE       pbHash      = NULL;
	DWORD       dwDataLen   = 0;
	//BYTE        Data1[]     = {0x70,0x61,0x73,0x73,0x77,0x6F,0x72,0x64};
	//BYTE        Data2[]     = {0x6D,0x65,0x73,0x73,0x61,0x67,0x65};
	HMAC_INFO   HmacInfo;

	//--------------------------------------------------------------------
	// Zero the HMAC_INFO structure and use the SHA1 algorithm for
	// hashing.

	ZeroMemory(&HmacInfo, sizeof(HmacInfo));
	HmacInfo.HashAlgid = CALG_SHA1;

	//--------------------------------------------------------------------
	// Acquire a handle to the default RSA cryptographic service provider.

	if (!CryptAcquireContext(
		&hProv,                   // handle of the CSP
		NULL,                     // key container name
		NULL,                     // CSP name
		PROV_RSA_FULL,            // provider type
		CRYPT_VERIFYCONTEXT))     // no key access is requested
	{
		_TRACE(" Error in AcquireContext 0x%08x \n",
			GetLastError());
		goto ErrorExit;
	}

	//--------------------------------------------------------------------
	// Derive a symmetric key from a hash object by performing the
	// following steps:
	//    1. Call CryptCreateHash to retrieve a handle to a hash object.
	//    2. Call CryptHashData to add a text string (password) to the 
	//       hash object.
	//    3. Call CryptDeriveKey to create the symmetric key from the
	//       hashed password derived in step 2.
	// You will use the key later to create an HMAC hash object. 

	if (!CryptCreateHash(
		hProv,                    // handle of the CSP
		CALG_SHA1,                // hash algorithm to use
		0,                        // hash key
		0,                        // reserved
		&hHash))                  // address of hash object handle
	{
		_TRACE("Error in CryptCreateHash 0x%08x \n",
			GetLastError());
		goto ErrorExit;
	}

	if (!CryptHashData(
		hHash,                    // handle of the hash object
		(BYTE*)keyBytes.c_str(),                    // password to hash
		(DWORD)keyBytes.size(),            // number of bytes of data to add
		0))                       // flags
	{
		_TRACE("Error in CryptHashData 0x%08x \n", 
			GetLastError());
		goto ErrorExit;
	}

	// key creation based on 
	// http://mirror.leaseweb.com/NetBSD/NetBSD-release-5-0/src/dist/wpa/src/crypto/crypto_cryptoapi.c
	struct {
		BLOBHEADER hdr;
		DWORD len;
		BYTE key[1024]; // TODO might want to dynamically allocate this, Should Be Fine though
	} key_blob;

	key_blob.hdr.bType = PLAINTEXTKEYBLOB;
	key_blob.hdr.bVersion = CUR_BLOB_VERSION;
	key_blob.hdr.reserved = 0;
	/*
	* Note: RC2 is not really used, but that can be used to
	* import HMAC keys of up to 16 byte long.
	* CRYPT_IPSEC_HMAC_KEY flag for CryptImportKey() is needed to
	* be able to import longer keys (HMAC-SHA1 uses 20-byte key).
	*/
	key_blob.hdr.aiKeyAlg = CALG_RC2;
	key_blob.len = (DWORD)keyBytes.size();
	ZeroMemory(key_blob.key, sizeof(key_blob.key));

	_ASSERTE(keyBytes.size() <= SIZEOF(key_blob.key));
	CopyMemory(key_blob.key, keyBytes.c_str(), min(keyBytes.size(), SIZEOF(key_blob.key)));

	if (!CryptImportKey(
		hProv, 
		(BYTE *)&key_blob,
		sizeof(key_blob), 
		0, 
		CRYPT_IPSEC_HMAC_KEY,
		&hKey)) 
	{
		_TRACE("Error in CryptImportKey 0x%08x \n", GetLastError());
		goto ErrorExit;
	}

	//--------------------------------------------------------------------
	// Create an HMAC by performing the following steps:
	//    1. Call CryptCreateHash to create a hash object and retrieve 
	//       a handle to it.
	//    2. Call CryptSetHashParam to set the instance of the HMAC_INFO 
	//       structure into the hash object.
	//    3. Call CryptHashData to compute a hash of the message.
	//    4. Call CryptGetHashParam to retrieve the size, in bytes, of
	//       the hash.
	//    5. Call malloc to allocate memory for the hash.
	//    6. Call CryptGetHashParam again to retrieve the HMAC hash.

	if (!CryptCreateHash(
		hProv,                    // handle of the CSP.
		CALG_HMAC,                // HMAC hash algorithm ID
		hKey,                     // key for the hash (see above)
		0,                        // reserved
		&hHmacHash))              // address of the hash handle
	{
		_TRACE("Error in CryptCreateHash 0x%08x \n", 
			GetLastError());
		goto ErrorExit;
	}

	if (!CryptSetHashParam(
		hHmacHash,                // handle of the HMAC hash object
		HP_HMAC_INFO,             // setting an HMAC_INFO object
		(BYTE*)&HmacInfo,         // the HMAC_INFO object
		0))                       // reserved
	{
		_TRACE("Error in CryptSetHashParam 0x%08x \n", 
			GetLastError());
		goto ErrorExit;
	}

	if (!CryptHashData(
		hHmacHash,                // handle of the HMAC hash object
		(BYTE*)data.c_str(),                    // message to hash
		(DWORD)data.size(),            // number of bytes of data to add
		0))                       // flags
	{
		_TRACE("Error in CryptHashData 0x%08x \n", 
			GetLastError());
		goto ErrorExit;
	}

	//--------------------------------------------------------------------
	// Call CryptGetHashParam twice. Call it the first time to retrieve
	// the size, in bytes, of the hash. Allocate memory. Then call 
	// CryptGetHashParam again to retrieve the hash value.

	if (!CryptGetHashParam(
		hHmacHash,                // handle of the HMAC hash object
		HP_HASHVAL,               // query on the hash value
		NULL,                     // filled on second call
		&dwDataLen,               // length, in bytes, of the hash
		0))
	{
		_TRACE("Error in CryptGetHashParam 0x%08x \n", 
			GetLastError());
		goto ErrorExit;
	}

	pbHash = (BYTE*)malloc(dwDataLen);
	if(NULL == pbHash) 
	{
		_TRACE("unable to allocate memory\n");
		goto ErrorExit;
	}

	if (!CryptGetHashParam(
		hHmacHash,                 // handle of the HMAC hash object
		HP_HASHVAL,                // query on the hash value
		pbHash,                    // pointer to the HMAC hash value
		&dwDataLen,                // length, in bytes, of the hash
		0))
	{
		_TRACE("Error in CryptGetHashParam 0x%08x \n", GetLastError());
		goto ErrorExit;
	}

	for(DWORD i = 0 ; i < dwDataLen ; i++) 
	{
		hash.push_back((char)pbHash[i]);
	}

	// Free resources.
	// lol goto
ErrorExit:
	if(hHmacHash)
		CryptDestroyHash(hHmacHash);
	if(hKey)
		CryptDestroyKey(hKey);
	if(hHash)
		CryptDestroyHash(hHash);    
	if(hProv)
		CryptReleaseContext(hProv, 0);
	if(pbHash)
		free(pbHash);

	return hash;
}

wstring mir_twitter::Base64String( const string& hash ) 
{
	Base64Coder coder;
	coder.Encode((BYTE*)hash.c_str(), (DWORD)hash.size());
	wstring encoded = UTF8ToWide(coder.EncodedMessage());
	return encoded;
}

wstring mir_twitter::OAuthCreateSignature( const wstring& signatureBase, const wstring& consumerSecret, const wstring& requestTokenSecret ) 
{
	// URL encode key elements
	wstring escapedConsumerSecret = UrlEncode(consumerSecret);
	wstring escapedTokenSecret = UrlEncode(requestTokenSecret);

	wstring key = escapedConsumerSecret + L"&" + escapedTokenSecret;
	string keyBytes = WideToUTF8(key);

	string data = WideToUTF8(signatureBase);
	string hash = HMACSHA1(keyBytes, data);
	wstring signature = Base64String(hash);

	// URL encode the returned signature
	signature = UrlEncode(signature);
	return signature;
}