From a8ced184dc67c5cf39ce1332156c7eb80241768b Mon Sep 17 00:00:00 2001 From: Adam Ierymenko Date: Thu, 20 Apr 2017 09:33:35 -0700 Subject: Some code cleanup and make sure any type punning is guarded with ZT_NO_TYPE_PUNNING. --- node/Packet.cpp | 60 ++++++++++++++++++++------------------------------------- 1 file changed, 21 insertions(+), 39 deletions(-) (limited to 'node/Packet.cpp') diff --git a/node/Packet.cpp b/node/Packet.cpp index 85b18cff..8a57dd55 100644 --- a/node/Packet.cpp +++ b/node/Packet.cpp @@ -1109,38 +1109,26 @@ void Packet::armor(const void *key,bool encryptPayload,unsigned int counter) setCipher(encryptPayload ? ZT_PROTO_CIPHER_SUITE__C25519_POLY1305_SALSA2012 : ZT_PROTO_CIPHER_SUITE__C25519_POLY1305_NONE); _salsa20MangleKey((const unsigned char *)key,mangledKey); - if (ZT_HAS_FAST_CRYPTO()) { - const unsigned int payloadLen = (encryptPayload) ? (size() - ZT_PACKET_IDX_VERB) : 0; + const unsigned int encryptLen = (encryptPayload) ? (size() - ZT_PACKET_IDX_VERB) : 0; uint64_t keyStream[(ZT_PROTO_MAX_PACKET_LENGTH + 64 + 8) / 8]; - ZT_FAST_SINGLE_PASS_SALSA2012(keyStream,payloadLen + 64,(data + ZT_PACKET_IDX_IV),mangledKey); - - uint64_t *ksptr = keyStream + 8; // encryption starts after first Salsa20 block - uint8_t *dptr = data + ZT_PACKET_IDX_VERB; - unsigned int ksrem = payloadLen; - while (ksrem >= 8) { - ksrem -= 8; - *(reinterpret_cast(dptr)) ^= *(ksptr++); - dptr += 8; - } - for(unsigned int i=0;i(ksptr)[i]; - } - + ZT_FAST_SINGLE_PASS_SALSA2012(keyStream,encryptLen + 64,(data + ZT_PACKET_IDX_IV),mangledKey); + Salsa20::memxor(data + ZT_PACKET_IDX_VERB,reinterpret_cast(keyStream + 8),encryptLen); uint64_t mac[2]; Poly1305::compute(mac,data + ZT_PACKET_IDX_VERB,size() - ZT_PACKET_IDX_VERB,keyStream); +#ifdef ZT_NO_TYPE_PUNNING memcpy(data + ZT_PACKET_IDX_MAC,mac,8); +#else + (*reinterpret_cast(data + ZT_PACKET_IDX_MAC)) = mac[0]; +#endif } else { Salsa20 s20(mangledKey,data + ZT_PACKET_IDX_IV); - uint64_t macKey[4]; s20.crypt12(ZERO_KEY,macKey,sizeof(macKey)); - uint8_t *const payload = data + ZT_PACKET_IDX_VERB; const unsigned int payloadLen = size() - ZT_PACKET_IDX_VERB; if (encryptPayload) s20.crypt12(payload,payload,payloadLen); - uint64_t mac[2]; Poly1305::compute(mac,payload,payloadLen,macKey); memcpy(data + ZT_PACKET_IDX_MAC,mac,8); @@ -1157,39 +1145,33 @@ bool Packet::dearmor(const void *key) if ((cs == ZT_PROTO_CIPHER_SUITE__C25519_POLY1305_NONE)||(cs == ZT_PROTO_CIPHER_SUITE__C25519_POLY1305_SALSA2012)) { _salsa20MangleKey((const unsigned char *)key,mangledKey); - if (ZT_HAS_FAST_CRYPTO()) { uint64_t keyStream[(ZT_PROTO_MAX_PACKET_LENGTH + 64 + 8) / 8]; ZT_FAST_SINGLE_PASS_SALSA2012(keyStream,((cs == ZT_PROTO_CIPHER_SUITE__C25519_POLY1305_SALSA2012) ? (payloadLen + 64) : 64),(data + ZT_PACKET_IDX_IV),mangledKey); - uint64_t mac[2]; Poly1305::compute(mac,payload,payloadLen,keyStream); +#ifdef ZT_NO_TYPE_PUNNING if (!Utils::secureEq(mac,data + ZT_PACKET_IDX_MAC,8)) - return false; // MAC failed, packet is corrupt, modified, or is not from the sender - - if (cs == ZT_PROTO_CIPHER_SUITE__C25519_POLY1305_SALSA2012) { - uint64_t *ksptr = keyStream + 8; // encryption starts after first Salsa20 block - uint8_t *dptr = data + ZT_PACKET_IDX_VERB; - unsigned int ksrem = payloadLen; - while (ksrem >= 8) { - ksrem -= 8; - *(reinterpret_cast(dptr)) ^= *(ksptr++); - dptr += 8; - } - for(unsigned int i=0;i(ksptr)[i]; - } - } + return false; +#else + if ((*reinterpret_cast(data + ZT_PACKET_IDX_MAC)) != mac[0]) // also secure, constant time + return false; +#endif + if (cs == ZT_PROTO_CIPHER_SUITE__C25519_POLY1305_SALSA2012) + Salsa20::memxor(data + ZT_PACKET_IDX_VERB,reinterpret_cast(keyStream + 8),payloadLen); } else { Salsa20 s20(mangledKey,data + ZT_PACKET_IDX_IV); - uint64_t macKey[4]; s20.crypt12(ZERO_KEY,macKey,sizeof(macKey)); uint64_t mac[2]; Poly1305::compute(mac,payload,payloadLen,macKey); +#ifdef ZT_NO_TYPE_PUNNING if (!Utils::secureEq(mac,data + ZT_PACKET_IDX_MAC,8)) - return false; // MAC failed, packet is corrupt, modified, or is not from the sender - + return false; +#else + if ((*reinterpret_cast(data + ZT_PACKET_IDX_MAC)) != mac[0]) // also secure, constant time + return false; +#endif if (cs == ZT_PROTO_CIPHER_SUITE__C25519_POLY1305_SALSA2012) s20.crypt12(payload,payload,payloadLen); } -- cgit v1.2.3