#include "AES.h" #include "CTR.h" #include "CryptoEngine.h" #include "configuration.h" class RP2040CryptoEngine : public CryptoEngine { CTRCommon *ctr = NULL; public: RP2040CryptoEngine() {} ~RP2040CryptoEngine() {} virtual void setKey(const CryptoKey &k) override { CryptoEngine::setKey(k); LOG_DEBUG("Installing AES%d key!\n", key.length * 8); if (ctr) { delete ctr; ctr = NULL; } if (key.length != 0) { if (key.length == 16) ctr = new CTR(); else ctr = new CTR(); ctr->setKey(key.bytes, key.length); } } /** * Encrypt a packet * * @param bytes is updated in place */ virtual void encrypt(uint32_t fromNode, uint64_t packetId, size_t numBytes, uint8_t *bytes) override { if (key.length > 0) { initNonce(fromNode, packetId); if (numBytes <= MAX_BLOCKSIZE) { static uint8_t scratch[MAX_BLOCKSIZE]; memcpy(scratch, bytes, numBytes); memset(scratch + numBytes, 0, sizeof(scratch) - numBytes); // Fill rest of buffer with zero (in case cypher looks at it) ctr->setIV(nonce, sizeof(nonce)); ctr->setCounterSize(4); ctr->encrypt(bytes, scratch, numBytes); } else { LOG_ERROR("Packet too large for crypto engine: %d. noop encryption!\n", numBytes); } } } virtual void decrypt(uint32_t fromNode, uint64_t packetId, size_t numBytes, uint8_t *bytes) override { // For CTR, the implementation is the same encrypt(fromNode, packetId, numBytes, bytes); } private: }; CryptoEngine *crypto = new RP2040CryptoEngine();