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Subject: Re: [Linux-ima-devel] [PATCH 0/7] IMA: new parser for
 ima_restore_measurement_list()
To: Ken Goldman <kgold@linux.vnet.ibm.com>,
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From: Roberto Sassu <roberto.sassu@huawei.com>
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Date: Thu, 18 May 2017 11:38:24 +0200
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On 5/17/2017 6:28 PM, Ken Goldman wrote:
> On 5/17/2017 3:25 AM, Roberto Sassu wrote:
>>
>> The format of digestN is: <algo name>:\0<digest value>, the same used
>> for the file digest.
>
> Since the format is changing from the SHA-1 log format anyway ...
>
> How do people feel about the colon and null terminated string format for
> algorithm identifiers?
>
> The TCG standard enumerations are uint16_t, and there is a registry of
> hash algorithms.
>
> As a consuming parser, it feels nice to know it's always 2 bytes and not
> have to worry about a missing colon or a missing nul terminator risking
> a buffer overflow.

There cannot be buffer overflow, because the length of each digest
field is known.

Roberto