Crypto++  8.8
Free C++ class library of cryptographic schemes
ida.cpp
1 // ida.cpp - originally written and placed in the public domain by Wei Dai
2 
3 #include "pch.h"
4 #include "config.h"
5 
6 #include "ida.h"
7 #include "stdcpp.h"
8 #include "algebra.h"
9 #include "polynomi.h"
10 #include "polynomi.cpp"
11 
12 NAMESPACE_BEGIN(CryptoPP)
13 
14 #if (defined(CRYPTOPP_MSC_VERSION) && (CRYPTOPP_MSC_VERSION < 1400)) && !defined(__MWERKS__)
15  // VC60 and VC7 workaround: built-in reverse_iterator has two template parameters, Dinkumware only has one
16  typedef std::reverse_bidirectional_iterator<const byte *, const byte> RevIt;
17 #elif defined(_RWSTD_NO_CLASS_PARTIAL_SPEC)
18  typedef std::reverse_iterator<const byte *, std::random_access_iterator_tag, const byte> RevIt;
19 #else
20  typedef std::reverse_iterator<const byte *> RevIt;
21 #endif
22 
23 void RawIDA::IsolatedInitialize(const NameValuePairs &parameters)
24 {
25  if (!parameters.GetIntValue("RecoveryThreshold", m_threshold))
26  throw InvalidArgument("RawIDA: missing RecoveryThreshold argument");
27 
28  CRYPTOPP_ASSERT(m_threshold > 0);
29  if (m_threshold <= 0)
30  throw InvalidArgument("RawIDA: RecoveryThreshold must be greater than 0");
31 
32  m_lastMapPosition = m_inputChannelMap.end();
33  m_channelsReady = 0;
34  m_channelsFinished = 0;
35  m_w.New(m_threshold);
36  m_y.New(m_threshold);
37  m_inputQueues.reserve(m_threshold);
38 
39  m_outputChannelIds.clear();
40  m_outputChannelIdStrings.clear();
41  m_outputQueues.clear();
42 
43  word32 outputChannelID;
44  if (parameters.GetValue("OutputChannelID", outputChannelID))
45  AddOutputChannel(outputChannelID);
46  else
47  {
48  int nShares = parameters.GetIntValueWithDefault("NumberOfShares", m_threshold);
49  CRYPTOPP_ASSERT(nShares > 0);
50  if (nShares <= 0) {nShares = m_threshold;}
51  for (unsigned int i=0; i< (unsigned int)(nShares); i++)
52  AddOutputChannel(i);
53  }
54 }
55 
56 unsigned int RawIDA::InsertInputChannel(word32 channelId)
57 {
58  if (m_lastMapPosition != m_inputChannelMap.end())
59  {
60  if (m_lastMapPosition->first == channelId)
61  goto skipFind;
62  ++m_lastMapPosition;
63  if (m_lastMapPosition != m_inputChannelMap.end() && m_lastMapPosition->first == channelId)
64  goto skipFind;
65  }
66  m_lastMapPosition = m_inputChannelMap.find(channelId);
67 
68 skipFind:
69  if (m_lastMapPosition == m_inputChannelMap.end())
70  {
71  if (m_inputChannelIds.size() == size_t(m_threshold))
72  return m_threshold;
73 
74  m_lastMapPosition = m_inputChannelMap.insert(InputChannelMap::value_type(channelId, (unsigned int)m_inputChannelIds.size())).first;
75  m_inputQueues.push_back(MessageQueue());
76  m_inputChannelIds.push_back(channelId);
77 
78  if (m_inputChannelIds.size() == size_t(m_threshold))
79  PrepareInterpolation();
80  }
81  return m_lastMapPosition->second;
82 }
83 
84 unsigned int RawIDA::LookupInputChannel(word32 channelId) const
85 {
86  std::map<word32, unsigned int>::const_iterator it = m_inputChannelMap.find(channelId);
87  if (it == m_inputChannelMap.end())
88  return m_threshold;
89  else
90  return it->second;
91 }
92 
93 void RawIDA::ChannelData(word32 channelId, const byte *inString, size_t length, bool messageEnd)
94 {
95  int i = InsertInputChannel(channelId);
96  if (i < m_threshold)
97  {
98  lword size = m_inputQueues[i].MaxRetrievable();
99  m_inputQueues[i].Put(inString, length);
100  if (size < 4 && size + length >= 4)
101  {
102  m_channelsReady++;
103  if (m_channelsReady == size_t(m_threshold))
104  ProcessInputQueues();
105  }
106 
107  if (messageEnd)
108  {
109  m_inputQueues[i].MessageEnd();
110  if (m_inputQueues[i].NumberOfMessages() == 1)
111  {
112  m_channelsFinished++;
113  if (m_channelsFinished == size_t(m_threshold))
114  {
115  m_channelsReady = 0;
116  for (i=0; i<m_threshold; i++)
117  m_channelsReady += m_inputQueues[i].AnyRetrievable();
118  ProcessInputQueues();
119  }
120  }
121  }
122  }
123 }
124 
125 lword RawIDA::InputBuffered(word32 channelId) const
126 {
127  int i = LookupInputChannel(channelId);
128  return i < m_threshold ? m_inputQueues[i].MaxRetrievable() : 0;
129 }
130 
131 void RawIDA::ComputeV(unsigned int i)
132 {
133  if (i >= m_v.size())
134  {
135  m_v.resize(i+1);
136  m_outputToInput.resize(i+1);
137  }
138 
139  m_outputToInput[i] = LookupInputChannel(m_outputChannelIds[i]);
140  if (m_outputToInput[i] == size_t(m_threshold) && i * size_t(m_threshold) <= 1000*1000)
141  {
142  m_v[i].resize(m_threshold);
143  PrepareBulkPolynomialInterpolationAt(m_gf32, m_v[i].begin(), m_outputChannelIds[i], &(m_inputChannelIds[0]), m_w.begin(), m_threshold);
144  }
145 }
146 
147 void RawIDA::AddOutputChannel(word32 channelId)
148 {
149  m_outputChannelIds.push_back(channelId);
150  m_outputChannelIdStrings.push_back(WordToString(channelId));
151  m_outputQueues.push_back(ByteQueue());
152  if (m_inputChannelIds.size() == size_t(m_threshold))
153  ComputeV((unsigned int)m_outputChannelIds.size() - 1);
154 }
155 
156 void RawIDA::PrepareInterpolation()
157 {
158  CRYPTOPP_ASSERT(m_inputChannelIds.size() == size_t(m_threshold));
159  PrepareBulkPolynomialInterpolation(m_gf32, m_w.begin(), &(m_inputChannelIds[0]), (unsigned int)(m_threshold));
160  for (unsigned int i=0; i<m_outputChannelIds.size(); i++)
161  ComputeV(i);
162 }
163 
164 void RawIDA::ProcessInputQueues()
165 {
166  bool finished = (m_channelsFinished == size_t(m_threshold));
167  unsigned int i;
168 
169  while (finished ? m_channelsReady > 0 : m_channelsReady == size_t(m_threshold))
170  {
171  m_channelsReady = 0;
172  for (i=0; i<size_t(m_threshold); i++)
173  {
174  MessageQueue &queue = m_inputQueues[i];
175  queue.GetWord32(m_y[i]);
176 
177  if (finished)
178  m_channelsReady += queue.AnyRetrievable();
179  else
180  m_channelsReady += queue.NumberOfMessages() > 0 || queue.MaxRetrievable() >= 4;
181  }
182 
183  for (i=0; (unsigned int)i<m_outputChannelIds.size(); i++)
184  {
185  if (m_outputToInput[i] != size_t(m_threshold))
186  m_outputQueues[i].PutWord32(m_y[m_outputToInput[i]]);
187  else if (m_v[i].size() == size_t(m_threshold))
188  m_outputQueues[i].PutWord32(BulkPolynomialInterpolateAt(m_gf32, m_y.begin(), m_v[i].begin(), m_threshold));
189  else
190  {
191  m_u.resize(m_threshold);
192  PrepareBulkPolynomialInterpolationAt(m_gf32, m_u.begin(), m_outputChannelIds[i], &(m_inputChannelIds[0]), m_w.begin(), m_threshold);
193  m_outputQueues[i].PutWord32(BulkPolynomialInterpolateAt(m_gf32, m_y.begin(), m_u.begin(), m_threshold));
194  }
195  }
196  }
197 
198  if (m_outputChannelIds.size() > 0 && m_outputQueues[0].AnyRetrievable())
199  FlushOutputQueues();
200 
201  if (finished)
202  {
203  OutputMessageEnds();
204 
205  m_channelsReady = 0;
206  m_channelsFinished = 0;
207  m_v.clear();
208 
209  std::vector<MessageQueue> inputQueues;
210  std::vector<word32> inputChannelIds;
211 
212  inputQueues.swap(m_inputQueues);
213  inputChannelIds.swap(m_inputChannelIds);
214  m_inputChannelMap.clear();
215  m_lastMapPosition = m_inputChannelMap.end();
216 
217  for (i=0; i<size_t(m_threshold); i++)
218  {
219  inputQueues[i].GetNextMessage();
220  inputQueues[i].TransferAllTo(*AttachedTransformation(), WordToString(inputChannelIds[i]));
221  }
222  }
223 }
224 
225 void RawIDA::FlushOutputQueues()
226 {
227  for (unsigned int i=0; i<m_outputChannelIds.size(); i++)
228  m_outputQueues[i].TransferAllTo(*AttachedTransformation(), m_outputChannelIdStrings[i]);
229 }
230 
231 void RawIDA::OutputMessageEnds()
232 {
233  if (GetAutoSignalPropagation() != 0)
234  {
235  for (unsigned int i=0; i<m_outputChannelIds.size(); i++)
236  AttachedTransformation()->ChannelMessageEnd(m_outputChannelIdStrings[i], GetAutoSignalPropagation()-1);
237  }
238 }
239 
240 // ****************************************************************
241 
243 {
244  m_pad = parameters.GetValueWithDefault("AddPadding", true);
245  m_ida.IsolatedInitialize(parameters);
246 }
247 
248 size_t SecretSharing::Put2(const byte *begin, size_t length, int messageEnd, bool blocking)
249 {
250  if (!blocking)
251  throw BlockingInputOnly("SecretSharing");
252 
253  SecByteBlock buf(UnsignedMin(256u, length));
254  unsigned int threshold = m_ida.GetThreshold();
255  while (length > 0)
256  {
257  size_t len = STDMIN(length, buf.size());
258  m_ida.ChannelData(0xffffffff, begin, len, false);
259  for (unsigned int i=0; i<threshold-1; i++)
260  {
261  m_rng.GenerateBlock(buf, len);
262  m_ida.ChannelData(i, buf, len, false);
263  }
264  length -= len;
265  begin += len;
266  }
267 
268  if (messageEnd)
269  {
270  m_ida.SetAutoSignalPropagation(messageEnd-1);
271  if (m_pad)
272  {
274  while (m_ida.InputBuffered(0xffffffff) > 0)
276  }
277  m_ida.ChannelData(0xffffffff, NULLPTR, 0, true);
278  for (unsigned int i=0; i<m_ida.GetThreshold()-1; i++)
279  m_ida.ChannelData(i, NULLPTR, 0, true);
280  }
281 
282  return 0;
283 }
284 
285 void SecretRecovery::IsolatedInitialize(const NameValuePairs &parameters)
286 {
287  m_pad = parameters.GetValueWithDefault("RemovePadding", true);
288  RawIDA::IsolatedInitialize(CombinedNameValuePairs(parameters, MakeParameters("OutputChannelID", (word32)0xffffffff)));
289 }
290 
291 void SecretRecovery::FlushOutputQueues()
292 {
293  if (m_pad)
294  m_outputQueues[0].TransferTo(*AttachedTransformation(), m_outputQueues[0].MaxRetrievable()-4);
295  else
296  m_outputQueues[0].TransferTo(*AttachedTransformation());
297 }
298 
299 void SecretRecovery::OutputMessageEnds()
300 {
301  if (m_pad)
302  {
303  PaddingRemover paddingRemover(new Redirector(*AttachedTransformation()));
304  m_outputQueues[0].TransferAllTo(paddingRemover);
305  }
306 
307  if (GetAutoSignalPropagation() != 0)
308  AttachedTransformation()->MessageEnd(GetAutoSignalPropagation()-1);
309 }
310 
311 // ****************************************************************
312 
314 {
315  m_nextChannel = 0;
316  m_pad = parameters.GetValueWithDefault("AddPadding", true);
317  m_ida.IsolatedInitialize(parameters);
318 }
319 
320 size_t InformationDispersal::Put2(const byte *begin, size_t length, int messageEnd, bool blocking)
321 {
322  if (!blocking)
323  throw BlockingInputOnly("InformationDispersal");
324 
325  while (length--)
326  {
327  m_ida.ChannelData(m_nextChannel, begin, 1, false);
328  begin++;
329  m_nextChannel++;
330  if (m_nextChannel == m_ida.GetThreshold())
331  m_nextChannel = 0;
332  }
333 
334  if (messageEnd)
335  {
336  m_ida.SetAutoSignalPropagation(messageEnd-1);
337  if (m_pad)
339  for (word32 i=0; i<m_ida.GetThreshold(); i++)
340  m_ida.ChannelData(i, NULLPTR, 0, true);
341  }
342 
343  return 0;
344 }
345 
346 void InformationRecovery::IsolatedInitialize(const NameValuePairs &parameters)
347 {
348  m_pad = parameters.GetValueWithDefault("RemovePadding", true);
349  RawIDA::IsolatedInitialize(parameters);
350 }
351 
352 void InformationRecovery::FlushOutputQueues()
353 {
354  while (m_outputQueues[0].AnyRetrievable())
355  {
356  for (unsigned int i=0; i<m_outputChannelIds.size(); i++)
357  m_outputQueues[i].TransferTo(m_queue, 1);
358  }
359 
360  if (m_pad)
361  m_queue.TransferTo(*AttachedTransformation(), m_queue.MaxRetrievable()-4*m_threshold);
362  else
363  m_queue.TransferTo(*AttachedTransformation());
364 }
365 
366 void InformationRecovery::OutputMessageEnds()
367 {
368  if (m_pad)
369  {
370  PaddingRemover paddingRemover(new Redirector(*AttachedTransformation()));
371  m_queue.TransferAllTo(paddingRemover);
372  }
373 
374  if (GetAutoSignalPropagation() != 0)
375  AttachedTransformation()->MessageEnd(GetAutoSignalPropagation()-1);
376 }
377 
378 size_t PaddingRemover::Put2(const byte *begin, size_t length, int messageEnd, bool blocking)
379 {
380  if (!blocking)
381  throw BlockingInputOnly("PaddingRemover");
382 
383  const byte *const end = begin + length;
384 
385  if (m_possiblePadding)
386  {
387  size_t len = FindIfNot(begin, end, byte(0)) - begin;
388  m_zeroCount += len;
389  begin += len;
390  if (begin == end)
391  return 0;
392 
394  while (m_zeroCount--)
396  AttachedTransformation()->Put(*begin++);
397  m_possiblePadding = false;
398  }
399 
400  const byte *x = FindIfNot(RevIt(end), RevIt(begin), byte(0)).base();
401  if (x != begin && *(x-1) == 1)
402  {
403  AttachedTransformation()->Put(begin, x-begin-1);
404  m_possiblePadding = true;
405  m_zeroCount = end - x;
406  }
407  else
408  AttachedTransformation()->Put(begin, end-begin);
409 
410  if (messageEnd)
411  {
412  m_possiblePadding = false;
413  Output(0, begin, length, messageEnd, blocking);
414  }
415  return 0;
416 }
417 
418 NAMESPACE_END
Classes for performing mathematics over different fields.
AlgorithmParameters MakeParameters(const char *name, const T &value, bool throwIfNotUsed=true)
Create an object that implements NameValuePairs.
Definition: algparam.h:508
int GetAutoSignalPropagation() const
Retrieve automatic signal propagation value.
Definition: simple.h:439
void SetAutoSignalPropagation(int propagation)
Set propagation of automatically generated and transferred signals.
Definition: simple.h:433
size_t GetWord32(word32 &value, ByteOrder order=BIG_ENDIAN_ORDER)
Retrieve a 32-bit word.
void TransferAllTo(BufferedTransformation &target, const std::string &channel=DEFAULT_CHANNEL)
Transfer all bytes from this object to another BufferedTransformation.
Definition: cryptlib.h:2098
lword TransferTo(BufferedTransformation &target, lword transferMax=LWORD_MAX, const std::string &channel=DEFAULT_CHANNEL)
move transferMax bytes of the buffered output to target as input
Definition: cryptlib.h:1996
size_t Put(byte inByte, bool blocking=true)
Input a byte for processing.
Definition: cryptlib.h:1678
Data structure used to store byte strings.
Definition: queue.h:23
lword MaxRetrievable() const
Provides the number of bytes ready for retrieval.
Definition: queue.h:40
Combines two sets of NameValuePairs.
Definition: algparam.h:129
BufferedTransformation * AttachedTransformation()
Retrieve attached transformation.
size_t Put2(const byte *begin, size_t length, int messageEnd, bool blocking)
Input multiple bytes for processing.
Definition: ida.cpp:320
void IsolatedInitialize(const NameValuePairs &parameters=g_nullNameValuePairs)
Initialize or reinitialize this object, without signal propagation.
Definition: ida.cpp:313
An invalid argument was detected.
Definition: cryptlib.h:208
Data structure used to store messages.
Definition: mqueue.h:24
bool AnyRetrievable() const
Determines whether bytes are ready for retrieval.
Definition: mqueue.h:54
unsigned int NumberOfMessages() const
Provides the number of meesages processed by this object.
Definition: mqueue.h:62
lword MaxRetrievable() const
Provides the number of bytes ready for retrieval.
Definition: mqueue.h:52
Interface for retrieving values given their names.
Definition: cryptlib.h:327
T GetValueWithDefault(const char *name, T defaultValue) const
Get a named value.
Definition: cryptlib.h:397
bool GetValue(const char *name, T &value) const
Get a named value.
Definition: cryptlib.h:384
CRYPTOPP_DLL int GetIntValueWithDefault(const char *name, int defaultValue) const
Get a named value with type int, with default.
Definition: cryptlib.h:429
CRYPTOPP_DLL bool GetIntValue(const char *name, int &value) const
Get a named value with type int.
Definition: cryptlib.h:420
size_t Put2(const byte *begin, size_t length, int messageEnd, bool blocking)
Input multiple bytes for processing.
Definition: ida.cpp:378
virtual void GenerateBlock(byte *output, size_t size)
Generate random array of bytes.
Redirect input to another BufferedTransformation without owning it.
Definition: filters.h:884
iterator begin()
Provides an iterator pointing to the first element in the memory block.
Definition: secblock.h:836
void New(size_type newSize)
Change size without preserving contents.
Definition: secblock.h:1126
size_type size() const
Provides the count of elements in the SecBlock.
Definition: secblock.h:867
void resize(size_type newSize)
Change size and preserve contents.
Definition: secblock.h:1198
SecBlock<byte> typedef.
Definition: secblock.h:1226
size_t Put2(const byte *begin, size_t length, int messageEnd, bool blocking)
Input multiple bytes for processing.
Definition: ida.cpp:248
void IsolatedInitialize(const NameValuePairs &parameters=g_nullNameValuePairs)
Initialize or reinitialize this object, without signal propagation.
Definition: ida.cpp:242
Library configuration file.
unsigned int word32
32-bit unsigned datatype
Definition: config_int.h:72
word64 lword
Large word type.
Definition: config_int.h:168
Classes for Rabin's Information Dispersal and Shamir's Secret Sharing algorithms.
std::string WordToString(T value, ByteOrder order=BIG_ENDIAN_ORDER)
Convert a word to a string.
Definition: misc.h:3065
InputIt FindIfNot(InputIt first, InputIt last, const T &value)
Finds first element not in a range.
Definition: misc.h:3190
const T & STDMIN(const T &a, const T &b)
Replacement function for std::min.
Definition: misc.h:657
const T1 UnsignedMin(const T1 &a, const T2 &b)
Safe comparison of values that could be negative and incorrectly promoted.
Definition: misc.h:695
Crypto++ library namespace.
Precompiled header file.
Classes for polynomial basis and operations.
Common C++ header files.
Exception thrown by objects that have not implemented nonblocking input processing.
Definition: cryptlib.h:1789
#define CRYPTOPP_ASSERT(exp)
Debugging and diagnostic assertion.
Definition: trap.h:68