Re: [PATCH RFC] crypto: keytoc: Split env-provided full keyspec on spaces

[Jonas Rebmann <jre@pengutronix.de>]

Hi Ahmad,

On 2026-02-10 10:35, Ahmad Fatoum wrote:
> On 2/6/26 1:28 PM, Jonas Rebmann wrote:
>> keytoc/CONFIG_CRYPTO_PUBLIC_KEYS can work with a complete keyspec
>> provided by an environment variable as opposed to providing single URIs.
>> This would be a very useful feature if it could also provide any number
>> of keys. Kconfig however provides keytoc with regular keyspecs already
>> split at spaces so without furhter measures, the env variable can only
>> be expanded into a single key.
>>
>> Work around this by, in the special case of keytoc provided with a
>> single environment variable, splitting that single argument at any space
>> character that is not escaped with a backslash in front of it.
> 
> I think that's sensible. Do we see breakage potential for existing
> users? If so, we should have a migration entry about the change in
> interpretation of space.

It does break for users of the single-env-variable format if they'd been
relying on paths containing spaces or backslashes, which they'd need to
start escaping now. But I don't suppose many, if any, users are really
affected by that.

I'll add a migration entry, suppose it can't hurt.

I'll update this patch to treat multiple variables the same way as
single variables.

Right now, given a single __ENV__var1 argument, that is split but once
given a second __ENV__var2 argument, neither are split, which is
inconsistent.

I will keep not modifying plain URIs provided by env e.g.
keyring:__ENV__uri

>>   	keycount = argc - optind;
>> +	keyspecs = argv + optind;
>> +
>> +	if (keycount == 1 && !strncmp(argv[optind], "__ENV__", 7)) {
>> +		char *singlespec = try_resolve_env(keyspecs[0]);
>> +		/* include '\0' in length */
>> +		int len = strlen(singlespec) + 1;
>> +		char *p;
>> +
>> +		for (p = singlespec; *p; p++) {
> 
> Can you copy strsep_unescaped to scripts/ and use that instead?

Oh yes that will make things easier.

Regards,
Jonas

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