use common context for ElGamal encrypt/decrypt

This commit is contained in:
orignal 2017-03-11 16:48:54 -05:00
parent 4bb607f180
commit c0c157ecef
7 changed files with 27 additions and 19 deletions

View file

@ -272,9 +272,8 @@ namespace crypto
} }
// ElGamal // ElGamal
void ElGamalEncrypt (const uint8_t * key, const uint8_t * data, uint8_t * encrypted, bool zeroPadding) void ElGamalEncrypt (const uint8_t * key, const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding)
{ {
BN_CTX * ctx = BN_CTX_new ();
BN_CTX_start (ctx); BN_CTX_start (ctx);
// everything, but a, because a might come from table // everything, but a, because a might come from table
BIGNUM * k = BN_CTX_get (ctx); BIGNUM * k = BN_CTX_get (ctx);
@ -324,13 +323,11 @@ namespace crypto
} }
BN_free (a); BN_free (a);
BN_CTX_end (ctx); BN_CTX_end (ctx);
BN_CTX_free (ctx);
} }
bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted, bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted,
uint8_t * data, bool zeroPadding) uint8_t * data, BN_CTX * ctx, bool zeroPadding)
{ {
BN_CTX * ctx = BN_CTX_new ();
BN_CTX_start (ctx); BN_CTX_start (ctx);
BIGNUM * x = BN_CTX_get (ctx), * a = BN_CTX_get (ctx), * b = BN_CTX_get (ctx); BIGNUM * x = BN_CTX_get (ctx), * a = BN_CTX_get (ctx), * b = BN_CTX_get (ctx);
BN_bin2bn (key, 256, x); BN_bin2bn (key, 256, x);
@ -343,7 +340,6 @@ namespace crypto
uint8_t m[255]; uint8_t m[255];
bn2buf (b, m, 255); bn2buf (b, m, 255);
BN_CTX_end (ctx); BN_CTX_end (ctx);
BN_CTX_free (ctx);
uint8_t hash[32]; uint8_t hash[32];
SHA256 (m + 33, 222, hash); SHA256 (m + 33, 222, hash);
if (memcmp (m + 1, hash, 32)) if (memcmp (m + 1, hash, 32))

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@ -48,8 +48,8 @@ namespace crypto
}; };
// ElGamal // ElGamal
void ElGamalEncrypt (const uint8_t * key, const uint8_t * data, uint8_t * encrypted, bool zeroPadding = false); void ElGamalEncrypt (const uint8_t * key, const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding = false);
bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted, uint8_t * data, bool zeroPadding = false); bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding = false);
void GenerateElGamalKeyPair (uint8_t * priv, uint8_t * pub); void GenerateElGamalKeyPair (uint8_t * priv, uint8_t * pub);
// HMAC // HMAC

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@ -187,7 +187,8 @@ namespace garlic
RAND_bytes (elGamal.preIV, 32); // Pre-IV RAND_bytes (elGamal.preIV, 32); // Pre-IV
uint8_t iv[32]; // IV is first 16 bytes uint8_t iv[32]; // IV is first 16 bytes
SHA256(elGamal.preIV, 32, iv); SHA256(elGamal.preIV, 32, iv);
i2p::crypto::ElGamalEncrypt (m_Destination->GetEncryptionPublicKey (), (uint8_t *)&elGamal, buf, true); i2p::crypto::ElGamalEncrypt (m_Destination->GetEncryptionPublicKey (),
(uint8_t *)&elGamal, buf, m_Owner->GetBNContext (), true);
m_Encryption.SetIV (iv); m_Encryption.SetIV (iv);
buf += 514; buf += 514;
len += 514; len += 514;
@ -388,9 +389,15 @@ namespace garlic
return size; return size;
} }
GarlicDestination::GarlicDestination (): m_NumTags (32) // 32 tags by default
{
m_Ctx = BN_CTX_new ();
}
GarlicDestination::~GarlicDestination () GarlicDestination::~GarlicDestination ()
{ {
BN_CTX_free (m_Ctx);
} }
void GarlicDestination::CleanUp () void GarlicDestination::CleanUp ()
@ -446,7 +453,7 @@ namespace garlic
{ {
// tag not found. Use ElGamal // tag not found. Use ElGamal
ElGamalBlock elGamal; ElGamalBlock elGamal;
if (length >= 514 && i2p::crypto::ElGamalDecrypt (GetEncryptionPrivateKey (), buf, (uint8_t *)&elGamal, true)) if (length >= 514 && i2p::crypto::ElGamalDecrypt (GetEncryptionPrivateKey (), buf, (uint8_t *)&elGamal, m_Ctx, true))
{ {
auto decryption = std::make_shared<i2p::crypto::CBCDecryption>(); auto decryption = std::make_shared<i2p::crypto::CBCDecryption>();
decryption->SetKey (elGamal.sessionKey); decryption->SetKey (elGamal.sessionKey);

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@ -153,11 +153,12 @@ namespace garlic
{ {
public: public:
GarlicDestination (): m_NumTags (32) {}; // 32 tags by default GarlicDestination ();
~GarlicDestination (); ~GarlicDestination ();
void CleanUp (); void CleanUp ();
void SetNumTags (int numTags) { m_NumTags = numTags; }; void SetNumTags (int numTags) { m_NumTags = numTags; };
BN_CTX * GetBNContext () const { return m_Ctx; };
std::shared_ptr<GarlicRoutingSession> GetRoutingSession (std::shared_ptr<const i2p::data::RoutingDestination> destination, bool attachLeaseSet); std::shared_ptr<GarlicRoutingSession> GetRoutingSession (std::shared_ptr<const i2p::data::RoutingDestination> destination, bool attachLeaseSet);
void CleanupExpiredTags (); void CleanupExpiredTags ();
void RemoveDeliveryStatusSession (uint32_t msgID); void RemoveDeliveryStatusSession (uint32_t msgID);
@ -188,7 +189,8 @@ namespace garlic
void HandleGarlicPayload (uint8_t * buf, size_t len, std::shared_ptr<i2p::tunnel::InboundTunnel> from); void HandleGarlicPayload (uint8_t * buf, size_t len, std::shared_ptr<i2p::tunnel::InboundTunnel> from);
private: private:
BN_CTX * m_Ctx;
// outgoing sessions // outgoing sessions
int m_NumTags; int m_NumTags;
std::mutex m_SessionsMutex; std::mutex m_SessionsMutex;

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@ -326,8 +326,9 @@ namespace i2p
if (!memcmp (record + BUILD_REQUEST_RECORD_TO_PEER_OFFSET, (const uint8_t *)i2p::context.GetRouterInfo ().GetIdentHash (), 16)) if (!memcmp (record + BUILD_REQUEST_RECORD_TO_PEER_OFFSET, (const uint8_t *)i2p::context.GetRouterInfo ().GetIdentHash (), 16))
{ {
LogPrint (eLogDebug, "I2NP: Build request record ", i, " is ours"); LogPrint (eLogDebug, "I2NP: Build request record ", i, " is ours");
BN_CTX * ctx = BN_CTX_new ();
i2p::crypto::ElGamalDecrypt (i2p::context.GetEncryptionPrivateKey (), record + BUILD_REQUEST_RECORD_ENCRYPTED_OFFSET, clearText); i2p::crypto::ElGamalDecrypt (i2p::context.GetEncryptionPrivateKey (), record + BUILD_REQUEST_RECORD_ENCRYPTED_OFFSET, clearText, ctx);
BN_CTX_free (ctx);
// replace record to reply // replace record to reply
if (i2p::context.AcceptsTunnels () && if (i2p::context.AcceptsTunnels () &&
i2p::tunnel::tunnels.GetTransitTunnels ().size () <= g_MaxNumTransitTunnels && i2p::tunnel::tunnels.GetTransitTunnels ().size () <= g_MaxNumTransitTunnels &&

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@ -51,6 +51,7 @@ namespace tunnel
uint8_t * records = msg->GetPayload () + 1; uint8_t * records = msg->GetPayload () + 1;
TunnelHopConfig * hop = m_Config->GetFirstHop (); TunnelHopConfig * hop = m_Config->GetFirstHop ();
int i = 0; int i = 0;
BN_CTX * ctx = BN_CTX_new ();
while (hop) while (hop)
{ {
uint32_t msgID; uint32_t msgID;
@ -59,7 +60,7 @@ namespace tunnel
else else
msgID = replyMsgID; msgID = replyMsgID;
int idx = recordIndicies[i]; int idx = recordIndicies[i];
hop->CreateBuildRequestRecord (records + idx*TUNNEL_BUILD_RECORD_SIZE, msgID); hop->CreateBuildRequestRecord (records + idx*TUNNEL_BUILD_RECORD_SIZE, msgID, ctx);
hop->recordIndex = idx; hop->recordIndex = idx;
i++; i++;
#ifdef WITH_EVENTS #ifdef WITH_EVENTS
@ -67,6 +68,7 @@ namespace tunnel
#endif #endif
hop = hop->next; hop = hop->next;
} }
BN_CTX_free (ctx);
#ifdef WITH_EVENTS #ifdef WITH_EVENTS
EmitTunnelEvent("tunnel.build", this, peers); EmitTunnelEvent("tunnel.build", this, peers);
#endif #endif

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@ -83,7 +83,7 @@ namespace tunnel
} }
} }
void CreateBuildRequestRecord (uint8_t * record, uint32_t replyMsgID) const void CreateBuildRequestRecord (uint8_t * record, uint32_t replyMsgID, BN_CTX * ctx) const
{ {
uint8_t clearText[BUILD_REQUEST_RECORD_CLEAR_TEXT_SIZE]; uint8_t clearText[BUILD_REQUEST_RECORD_CLEAR_TEXT_SIZE];
htobe32buf (clearText + BUILD_REQUEST_RECORD_RECEIVE_TUNNEL_OFFSET, tunnelID); htobe32buf (clearText + BUILD_REQUEST_RECORD_RECEIVE_TUNNEL_OFFSET, tunnelID);
@ -101,7 +101,7 @@ namespace tunnel
htobe32buf (clearText + BUILD_REQUEST_RECORD_REQUEST_TIME_OFFSET, i2p::util::GetHoursSinceEpoch ()); htobe32buf (clearText + BUILD_REQUEST_RECORD_REQUEST_TIME_OFFSET, i2p::util::GetHoursSinceEpoch ());
htobe32buf (clearText + BUILD_REQUEST_RECORD_SEND_MSG_ID_OFFSET, replyMsgID); htobe32buf (clearText + BUILD_REQUEST_RECORD_SEND_MSG_ID_OFFSET, replyMsgID);
RAND_bytes (clearText + BUILD_REQUEST_RECORD_PADDING_OFFSET, BUILD_REQUEST_RECORD_CLEAR_TEXT_SIZE - BUILD_REQUEST_RECORD_PADDING_OFFSET); RAND_bytes (clearText + BUILD_REQUEST_RECORD_PADDING_OFFSET, BUILD_REQUEST_RECORD_CLEAR_TEXT_SIZE - BUILD_REQUEST_RECORD_PADDING_OFFSET);
i2p::crypto::ElGamalEncrypt (ident->GetEncryptionPublicKey (), clearText, record + BUILD_REQUEST_RECORD_ENCRYPTED_OFFSET); i2p::crypto::ElGamalEncrypt (ident->GetEncryptionPublicKey (), clearText, record + BUILD_REQUEST_RECORD_ENCRYPTED_OFFSET, ctx);
memcpy (record + BUILD_REQUEST_RECORD_TO_PEER_OFFSET, (const uint8_t *)ident->GetIdentHash (), 16); memcpy (record + BUILD_REQUEST_RECORD_TO_PEER_OFFSET, (const uint8_t *)ident->GetIdentHash (), 16);
} }
}; };