Re: [LTP] [PATCH v2 1/1] tst_af_alg: Another fix for disabled weak cipher

[Petr Vorel <pvorel@suse.cz>]

Hi Cyril,

[ Cc Eric ]
> Hi!
> > e.g. md5 on enabled FIPS.
> > Similar fix to 4fa302ef9d. It fixes:

> > ./af_alg01
> > tst_af_alg.c:84: TBROK: unexpected error binding AF_ALG socket to hash algorithm 'md5': ELIBBAD (80)
> > become
> > tst_fips.c:22: TINFO: FIPS: on
> > tst_af_alg.c:82: TCONF: FIPS enabled => hash algorithm 'md5' disabled
> > tst_fips.c:22: TINFO: FIPS: on
> > tst_af_alg.c:82: TCONF: FIPS enabled => hash algorithm 'md5-generic' disabled

> > ./af_alg02
> > tst_af_alg.c:37: TBROK: unexpected error binding AF_ALG socket to skcipher algorithm 'salsa20': ELIBBAD (80)
> > become
> > tst_fips.c:22: TINFO: FIPS: on
> > tst_af_alg.c:36: TCONF: FIPS enabled => skcipher algorithm 'salsa20' disabled

> > ./af_alg04
> > tst_af_alg.c:81: TBROK: unexpected error binding AF_ALG socket to hash algorithm 'vmac64(aes)': ELIBBAD (80)
> > become
> > tst_fips.c:22: TINFO: FIPS: on
> > tst_af_alg.c:82: TCONF: FIPS enabled => hash algorithm 'vmac64(aes)' disabled
> > af_alg04.c:32: TCONF: kernel doesn't have hash algorithm 'vmac(aes)'
> > af_alg04.c:32: TCONF: kernel doesn't have hash algorithm 'vmac(sm4)'
> > af_alg04.c:32: TCONF: kernel doesn't have hash algorithm 'vmac(sm4-generic)'

> > af_alg01.c adjusted not to print TCONF twice.

> > Tested on Debian stable bullseye and SLES 15-SP4.

> > Signed-off-by: Petr Vorel <pvorel@suse.cz>
> > ---
> > Hi,

> > I was wrong, although SUSE has some custom patches for FIPS to disable
> > ciphers in drivers/crypto, patch is for mainline, because it returns
> > ELIBBAD for algorithms it considers non-FIPS-approved.

> > Also, while it's not that easy to run fips=1 on current openSUSE
> > Tumbleweed or Fedora 34 (there are probably some restricted ciphers
> > boot (systemd?) depends on), at least Debian stable boots and restrict
> > ciphers as expected.

> > NOTE: do we want to optimize repeated fips detection or repeated output?
> > (didn't see any elegant solution).

> > Kind regards,
> > Petr

> >  include/tst_af_alg.h               |  3 ++-
> >  lib/tst_af_alg.c                   | 16 +++++++++++++++-
> >  testcases/kernel/crypto/af_alg01.c |  6 ++++--
> >  3 files changed, 21 insertions(+), 4 deletions(-)

> > diff --git a/include/tst_af_alg.h b/include/tst_af_alg.h
> > index fd2ff06478..264e226a2c 100644
> > --- a/include/tst_af_alg.h
> > +++ b/include/tst_af_alg.h
> > @@ -61,7 +61,8 @@ void tst_alg_bind(int algfd, const char *algtype, const char *algname);
> >   * @param algname The name of the algorithm, such as "sha256" or "xts(aes)"
> >   *
> >   * Return true if the algorithm is available, or false if unavailable.
> > - * If another error occurs, tst_brk() is called with TBROK.
> > + * If another error occurs, tst_brk() is called with TBROK,
> > + * unless algorithm enabled due FIPS mode (errno ELIBBAD).
>                       ^
> 		      is disabled

Thanks!

> >   */
> >  bool tst_have_alg(const char *algtype, const char *algname);

> > diff --git a/lib/tst_af_alg.c b/lib/tst_af_alg.c
> > index 05caa63016..9325a98432 100644
> > --- a/lib/tst_af_alg.c
> > +++ b/lib/tst_af_alg.c
> > @@ -1,6 +1,7 @@
> >  // SPDX-License-Identifier: GPL-2.0-or-later
> >  /*
> >   * Copyright 2019 Google LLC
> > + * Copyright (c) Linux Test Project, 2019-2021
> >   */

> >  #include <errno.h>
> > @@ -30,10 +31,18 @@ void tst_alg_bind_addr(int algfd, const struct sockaddr_alg *addr)

> >  	if (ret == 0)
> >  		return;
> > +
> > +	if (errno == ELIBBAD && tst_fips_enabled()) {
> > +		tst_brk(TCONF,
> > +			"FIPS enabled => %s algorithm '%s' disabled",
> > +			addr->salg_type, addr->salg_name);
> > +	}
> > +
> >  	if (errno == ENOENT) {
> >  		tst_brk(TCONF, "kernel doesn't support %s algorithm '%s'",
> >  			addr->salg_type, addr->salg_name);
> >  	}
> > +
> >  	tst_brk(TBROK | TERRNO,
> >  		"unexpected error binding AF_ALG socket to %s algorithm '%s'",
> >  		addr->salg_type, addr->salg_name);
> > @@ -77,11 +86,16 @@ bool tst_have_alg(const char *algtype, const char *algname)

> >  	ret = bind(algfd, (const struct sockaddr *)&addr, sizeof(addr));
> >  	if (ret != 0) {
> > -		if (errno != ENOENT) {
> > +		if (errno == ELIBBAD && tst_fips_enabled()) {
> > +			tst_res(TCONF,
> > +				"FIPS enabled => %s algorithm '%s' disabled",
> > +				algtype, algname);
> > +		} else if (errno != ENOENT) {
> >  			tst_brk(TBROK | TERRNO,
> >  				"unexpected error binding AF_ALG socket to %s algorithm '%s'",
> >  				algtype, algname);
> >  		}
> > +
> >  		have_alg = false;
> >  	}

> > diff --git a/testcases/kernel/crypto/af_alg01.c b/testcases/kernel/crypto/af_alg01.c
> > index 47292ee328..e31126fe01 100644
> > --- a/testcases/kernel/crypto/af_alg01.c
> > +++ b/testcases/kernel/crypto/af_alg01.c
> > @@ -1,6 +1,7 @@
> >  // SPDX-License-Identifier: GPL-2.0-or-later
> >  /*
> >   * Copyright 2019 Google LLC
> > + * Copyright (c) Linux Test Project, 2019-2021
> >   */

> >  /*
> > @@ -22,8 +23,9 @@ static void test_with_hash_alg(const char *hash_algname)
> >  	char key[4096] = { 0 };

> >  	if (!tst_have_alg("hash", hash_algname)) {
> > -		tst_res(TCONF, "kernel doesn't have hash algorithm '%s'",
> > -			hash_algname);
> > +		if (errno != ELIBBAD)
> > +			tst_res(TCONF, "kernel doesn't have hash algorithm '%s'",
> > +				hash_algname);

> What about moving the tst_res(TCONF, ...) in the case of ENOENT to the
> tst_have_alg() function?

> That way we would have here just

> 	if (!tst_have_alg("hash", hash_algname))
> 		return;

Hm, if I haven't overlook anything, it could work even for af_alg04.c,
which uses it !tst_have_alg() once without TCONF:

 28     sprintf(vmac_algname, "vmac64(%s)", symm_enc_algname);
 29     if (!tst_have_alg("hash", vmac_algname)) {
 30         sprintf(vmac_algname, "vmac(%s)", symm_enc_algname);

Moved to tst_have_alg():
tst_fips.c:22: TINFO: FIPS: on
tst_af_alg.c:90: TCONF: FIPS enabled => hash algorithm 'vmac64(aes)' disabled
tst_af_alg.c:94: TCONF: kernel doesn't have hash algorithm 'vmac(aes)'
tst_af_alg.c:94: TCONF: kernel doesn't have hash algorithm 'vmac64(sm4)'
tst_af_alg.c:94: TCONF: kernel doesn't have hash algorithm 'vmac(sm4)'
tst_af_alg.c:94: TCONF: kernel doesn't have hash algorithm 'vmac64(sm4-generic)'
tst_af_alg.c:94: TCONF: kernel doesn't have hash algorithm 'vmac(sm4-generic)'

=> I'll send v3.

Kind regards,
Petr

> Other than these two minor things this version does look good:

> Reviewed-by: Cyril Hrubis <chrubis@suse.cz>

> >  		return;
> >  	}
> >  	sprintf(hmac_algname, "hmac(%s)", hash_algname);
> > -- 
> > 2.34.1

-- 
Mailing list info: https://lists.linux.it/listinfo/ltp