From 1e75de9bb80d19f48d2cb6b2f0b4a609f6d233ed Mon Sep 17 00:00:00 2001 From: orignal Date: Wed, 8 Nov 2017 21:06:58 -0500 Subject: [PATCH] 514 bytes ECIES block --- libi2pd/Crypto.cpp | 18 ++++++++++-------- libi2pd/Crypto.h | 2 +- 2 files changed, 11 insertions(+), 9 deletions(-) diff --git a/libi2pd/Crypto.cpp b/libi2pd/Crypto.cpp index 13c86188..ddd42f0d 100644 --- a/libi2pd/Crypto.cpp +++ b/libi2pd/Crypto.cpp @@ -385,10 +385,11 @@ namespace crypto auto p = EC_POINT_new (curve); EC_POINT_mul (curve, p, k, nullptr, nullptr, ctx); BIGNUM * x = BN_CTX_get (ctx), * y = BN_CTX_get (ctx); - EC_POINT_get_affine_coordinates_GFp (curve, p, x, y, nullptr); - bn2buf (x, encrypted, len); - bn2buf (y, encrypted + len, len); - RAND_bytes (encrypted + 2*len, 256 - 2*len); + EC_POINT_get_affine_coordinates_GFp (curve, p, x, y, nullptr); + encrypted[0] = 0; + bn2buf (x, encrypted + 1, len); + bn2buf (y, encrypted + 1 + len, len); + RAND_bytes (encrypted + 1 + 2*len, 256 - 2*len); // ecryption key and iv EC_POINT_mul (curve, p, nullptr, key, k, ctx); EC_POINT_get_affine_coordinates_GFp (curve, p, x, y, nullptr); @@ -402,10 +403,11 @@ namespace crypto memcpy (m+33, data, 222); SHA256 (m+33, 222, m+1); // encrypt + encrypted[257] = 0; CBCEncryption encryption; encryption.SetKey (shared); encryption.SetIV (iv); - encryption.Encrypt (m, 256, encrypted + 256); + encryption.Encrypt (m, 256, encrypted + 258); EC_POINT_free (p); BN_CTX_end (ctx); } @@ -419,8 +421,8 @@ namespace crypto int len = BN_num_bytes (q); // point for shared secret BIGNUM * x = BN_CTX_get (ctx), * y = BN_CTX_get (ctx); - BN_bin2bn (encrypted, len, x); - BN_bin2bn (encrypted + len, len, y); + BN_bin2bn (encrypted + 1, len, x); + BN_bin2bn (encrypted + 1 + len, len, y); auto p = EC_POINT_new (curve); if (EC_POINT_set_affine_coordinates_GFp (curve, p, x, y, nullptr)) { @@ -437,7 +439,7 @@ namespace crypto CBCDecryption decryption; decryption.SetKey (shared); decryption.SetIV (iv); - decryption.Decrypt (encrypted + 256, 256, m); + decryption.Decrypt (encrypted + 258, 256, m); // verify and copy uint8_t hash[32]; SHA256 (m + 33, 222, hash); diff --git a/libi2pd/Crypto.h b/libi2pd/Crypto.h index 68378b4e..2b1bf6a0 100644 --- a/libi2pd/Crypto.h +++ b/libi2pd/Crypto.h @@ -53,7 +53,7 @@ namespace crypto void GenerateElGamalKeyPair (uint8_t * priv, uint8_t * pub); // ECIES - void ECIESEncrypt (const EC_GROUP * curve, const EC_POINT * key, const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx); // 222 bytes data, 512 bytes encrypted + void ECIESEncrypt (const EC_GROUP * curve, const EC_POINT * key, const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx); // 222 bytes data, 514 bytes encrypted bool ECIESDecrypt (const EC_GROUP * curve, const BIGNUM * key, const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx); void GenerateECIESKeyPair (const EC_GROUP * curve, BIGNUM *& priv, EC_POINT *& pub);