From 56a5592ea034300c241505f32f4ed6eab673f223 Mon Sep 17 00:00:00 2001 From: Gustav Simonsson Date: Wed, 13 May 2015 18:33:31 +0200 Subject: [PATCH] Update keystore code comments --- crypto/key_store_passphrase.go | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/crypto/key_store_passphrase.go b/crypto/key_store_passphrase.go index d9a5a81f9..782f92bf1 100644 --- a/crypto/key_store_passphrase.go +++ b/crypto/key_store_passphrase.go @@ -28,21 +28,22 @@ the private key is encrypted and on disk uses another JSON encoding. Cryptography: -1. Encryption key is first 16 bytes of SHA3-256 of first 16 bytes of - scrypt derived key from user passphrase. Scrypt parameters +1. Encryption key is first 16 bytes of scrypt derived key + from user passphrase. Scrypt parameters (work factors) [1][2] are defined as constants below. 2. Scrypt salt is 32 random bytes from CSPRNG. - It's stored in plain next to ciphertext in key file. -3. MAC is SHA3-256 of concatenation of ciphertext and last 16 bytes of scrypt derived key. + It's stored in plain next in the key file. +3. MAC is SHA3-256 of concatenation of ciphertext and + last 16 bytes of scrypt derived key. 4. Plaintext is the EC private key bytes. 5. Encryption algo is AES 128 CBC [3][4] 6. CBC IV is 16 random bytes from CSPRNG. - It's stored in plain next to ciphertext in key file. + It's stored in plain next in the key file. 7. Plaintext padding is PKCS #7 [5][6] Encoding: -1. On disk, the ciphertext, MAC, salt and IV are encoded in a nested JSON object. +1. On disk, the ciphertext, MAC, salt and IV are encoded in a JSON object. cat a key file to see the structure. 2. byte arrays are base64 JSON strings. 3. The EC private key bytes are in uncompressed form [7].