diff options
Diffstat (limited to 'protocols/WhatsAppWeb/src/utils.cpp')
| -rw-r--r-- | protocols/WhatsAppWeb/src/utils.cpp | 49 |
1 files changed, 48 insertions, 1 deletions
diff --git a/protocols/WhatsAppWeb/src/utils.cpp b/protocols/WhatsAppWeb/src/utils.cpp index d956471e48..fba42e8b8d 100644 --- a/protocols/WhatsAppWeb/src/utils.cpp +++ b/protocols/WhatsAppWeb/src/utils.cpp @@ -7,6 +7,8 @@ Copyright © 2019 George Hazan #include "stdafx.h" +#define sharedKey(A, B, C) crypto_scalarmult((unsigned char*)A, (const unsigned char*)B, (const unsigned char*)C) + WAUser* WhatsAppProto::FindUser(const char *szId) { mir_cslock lck(m_csUsers); @@ -234,6 +236,31 @@ void WANoise::mixIntoKey(const void *pData, size_t cbLen) readCounter = writeCounter = 0; } +void WANoise::decrypt(const void *pData, size_t cbLen, MBinBuffer &dest) +{ + uint8_t iv[12]; + memset(iv, 0, 8); + memcpy(iv + 8, (bInitFinished) ? &readCounter : &writeCounter, sizeof(int)); + + uint8_t outbuf[1024 + EVP_MAX_BLOCK_LENGTH]; + + int dec_len = 0, final_len = 0; + EVP_CIPHER_CTX *ctx = EVP_CIPHER_CTX_new(); + EVP_DecryptInit_ex(ctx, EVP_aes_256_gcm(), NULL, (BYTE *)decKey.data(), iv); + for (size_t len = 0; len < cbLen; len += 1024) { + size_t portionSize = cbLen - len; + EVP_DecryptUpdate(ctx, outbuf, &dec_len, (BYTE*)pData + len, min(portionSize, 1024)); + if (len == 0) + dest.assign(outbuf, dec_len); + else + dest.append(outbuf, dec_len); + } + EVP_DecryptFinal_ex(ctx, outbuf, &final_len); + if (final_len) + dest.append(outbuf, final_len); + EVP_CIPHER_CTX_free(ctx); +} + bool WANoise::decodeFrame(const void *pData, size_t cbLen) { if (!bInitFinished) { @@ -243,10 +270,25 @@ bool WANoise::decodeFrame(const void *pData, size_t cbLen) auto &static_ = msg.serverhello().static_(); auto &payload = msg.serverhello().payload(); + uint8_t tmp[32]; + updateHash(ephemeral.c_str(), ephemeral.size()); - mixIntoKey(ephemeral.c_str(), ephemeral.size()); + sharedKey(tmp, privKey.data(), ephemeral.c_str()); + mixIntoKey(tmp, sizeof(tmp)); + + MBinBuffer decryptedStatic, decryptedCert; + decrypt(static_.c_str(), static_.size(), decryptedStatic); + + sharedKey(tmp, privKey.data(), decryptedStatic.data()); + mixIntoKey(tmp, sizeof(tmp)); + decrypt(payload.c_str(), payload.size(), decryptedCert); + + proto::CertChain cert; cert.ParseFromArray(decryptedCert.data(), (int)decryptedCert.length()); + proto::CertChain::NoiseCertificate::Details details; details.ParseFromString(cert.intermediate().details()); + if (details.issuerserial() != 0) + return false; } return true; } @@ -271,6 +313,11 @@ void WANoise::encodeFrame(const void *pData, size_t cbLen, MBinBuffer &res) res.append(pData, cbLen); } +void WANoise::encrypt(const void *pData, size_t cbLen, MBinBuffer &dest) +{ + +} + void WANoise::updateHash(const void *pData, size_t cbLen) { if (bInitFinished) |