2010-09-03 15:42:36 +00:00
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USB communication
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=================
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2010-12-08 05:10:30 +00:00
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* No command chaining, but extended APDU and extended Lc and Le.
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I think that this keep the code simple.
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2010-09-05 16:55:29 +00:00
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2011-01-28 08:38:52 +00:00
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* Once in the past (version <= 0.4), the value of
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dwMaxCCIDMessageLength was 64 and we supported ICC block chaining,
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so that we could not handle multple Bulk transactions.
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2010-12-08 05:10:30 +00:00
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* Now, the value of dwMaxCCIDMessageLength is 320, that's the size
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of header of ICC block plus size of maximum APDU (by 64
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2011-01-28 08:38:52 +00:00
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granularity). Still, some ccid implementation (ccid 1.3.11, for
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example) sends ICC block using chaining unfortunately, so we keep
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the code of ICC block chaining.
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2010-09-03 15:42:36 +00:00
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OpenPGP card protocol implementation
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====================================
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2010-12-08 05:10:30 +00:00
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I try to follow "no clear password(s)" policy, even if it is on
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protected flash memory. Futher, keystrings for user and reset code
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are removed after key imports. Because of this, replacing keys
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are not possible without password information. Thus, replacing
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existing keys are not supported.
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2010-09-03 15:42:36 +00:00
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2010-09-05 16:55:29 +00:00
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How a private key is stored
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===========================
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2010-09-03 15:42:36 +00:00
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KEYPTR
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----> [ P ][ Q ][ N ]
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<---encrypted----><--- plain ---->
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key_addr 4-byte
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additional_data_encrypted 16-byte
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dek_encrypted_by_keystring_pw1 16-byte
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dek_encrypted_by_keystring_rc 16-byte
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dek_encrypted_by_keystring_pw3 16-byte
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... decrypted to
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[ P ][ Q ]
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check 4-byte
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random 4-byte
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magic[] 8-byte
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