* [PATCH] KEYS: revert requiring signature "encoding"
@ 2018-11-09 5:59 Mimi Zohar
2018-11-09 13:16 ` David Howells
2018-11-09 15:28 ` David Howells
0 siblings, 2 replies; 6+ messages in thread
From: Mimi Zohar @ 2018-11-09 5:59 UTC (permalink / raw)
To: David Howells
Cc: Mimi Zohar, keyrings, linux-integrity, linux-security-module
Attempting to verify IMA signatures fail causing the system to hang.
Fixes: commit 82f94f24475c ("KEYS: Provide software public key query
function [ver #2]")
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
---
crypto/asymmetric_keys/public_key.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index f5d85b47fcc6..f90360122090 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -239,9 +239,17 @@ int public_key_verify_signature(const struct public_key *pkey,
BUG_ON(!sig);
BUG_ON(!sig->s);
- ret = software_key_determine_akcipher(sig->encoding,
- sig->hash_algo,
- pkey, alg_name);
+ if (!sig->digest)
+ return -ENOPKG;
+
+ if (!(sig->encoding) && strcmp(pkey->pkey_algo, "rsa") == 0)
+ ret = software_key_determine_akcipher("pkcs1",
+ sig->hash_algo,
+ pkey, alg_name);
+ else
+ ret = software_key_determine_akcipher(sig->encoding,
+ sig->hash_algo,
+ pkey, alg_name);
if (ret < 0)
return ret;
--
2.7.5
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] KEYS: revert requiring signature "encoding"
2018-11-09 5:59 [PATCH] KEYS: revert requiring signature "encoding" Mimi Zohar
@ 2018-11-09 13:16 ` David Howells
2018-11-09 14:14 ` Mimi Zohar
` (2 more replies)
2018-11-09 15:28 ` David Howells
1 sibling, 3 replies; 6+ messages in thread
From: David Howells @ 2018-11-09 13:16 UTC (permalink / raw)
To: Mimi Zohar; +Cc: dhowells, keyrings, linux-integrity, linux-security-module
Mimi Zohar <zohar@linux.ibm.com> wrote:
> Attempting to verify IMA signatures fail causing the system to hang.
Can you say why?
> Fixes: commit 82f94f24475c ("KEYS: Provide software public key query
> function [ver #2]")
Btw, no word "commit" after Fixes:.
David
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] KEYS: revert requiring signature "encoding"
2018-11-09 13:16 ` David Howells
@ 2018-11-09 14:14 ` Mimi Zohar
2018-11-09 15:05 ` David Howells
2018-11-09 15:06 ` David Howells
2 siblings, 0 replies; 6+ messages in thread
From: Mimi Zohar @ 2018-11-09 14:14 UTC (permalink / raw)
To: David Howells; +Cc: keyrings, linux-integrity, linux-security-module
On Fri, 2018-11-09 at 13:16 +0000, David Howells wrote:
> Mimi Zohar <zohar@linux.ibm.com> wrote:
>
> > Attempting to verify IMA signatures fail causing the system to hang.
>
> Can you say why?
On systems with IMA-appraisal enabled with a policy requiring file
signatures, the "good" signature values are stored on the filesystem
as extended attributes (security.ima). Signature verification failure
would normally be limited to just a particular file (eg. executable),
but during boot signature verification failure could result in a
system hang.
Removing existing signature formats breaks existing systems. This
patch adds support for RSA signatures without an explicit "pkcs1" sig-
>encoding.
>
> > Fixes: commit 82f94f24475c ("KEYS: Provide software public key query
> > function [ver #2]")
>
> Btw, no word "commit" after Fixes:.
Ok.
Looking the patch over again, do you prefer the duplicate call or
defining a local variable and using the ternary conditional operator
("?:") like this:
bool rsa = false;
if (!(sig->encoding) && strcmp(pkey->pkey_algo, "rsa") == 0)
rsa = true;
ret = software_key_determine_akcipher(rsa ? "pkcs1" : sig->encoding,
sig->hash_algo,
pkey, alg_name);
Mimi
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] KEYS: revert requiring signature "encoding"
2018-11-09 13:16 ` David Howells
2018-11-09 14:14 ` Mimi Zohar
@ 2018-11-09 15:05 ` David Howells
2018-11-09 15:06 ` David Howells
2 siblings, 0 replies; 6+ messages in thread
From: David Howells @ 2018-11-09 15:05 UTC (permalink / raw)
To: Mimi Zohar; +Cc: dhowells, keyrings, linux-integrity, linux-security-module
Mimi Zohar <zohar@linux.ibm.com> wrote:
> Looking the patch over again, do you prefer the duplicate call or
> defining a local variable and using the ternary conditional operator
> ("?:") like this:
>
> bool rsa = false;
>
> if (!(sig->encoding) && strcmp(pkey->pkey_algo, "rsa") == 0)
> rsa = true;
>
> ret = software_key_determine_akcipher(rsa ? "pkcs1" : sig->encoding,
> sig->hash_algo,
> pkey, alg_name);
Might be better to do:
const char *encoding = sig->encoding;
if (!encoding && strcmp(pkey->pkey_algo, "rsa") == 0)
encoding = "pkcs1";
ret = software_key_determine_akcipher(encoding, ...
David
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] KEYS: revert requiring signature "encoding"
2018-11-09 13:16 ` David Howells
2018-11-09 14:14 ` Mimi Zohar
2018-11-09 15:05 ` David Howells
@ 2018-11-09 15:06 ` David Howells
2 siblings, 0 replies; 6+ messages in thread
From: David Howells @ 2018-11-09 15:06 UTC (permalink / raw)
To: Mimi Zohar
Cc: dhowells, keyrings, linux-integrity, linux-security-module,
Denis Kenzior
And can you cc: Denis Kenzior <denkenz@gmail.com> too?
David
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] KEYS: revert requiring signature "encoding"
2018-11-09 5:59 [PATCH] KEYS: revert requiring signature "encoding" Mimi Zohar
2018-11-09 13:16 ` David Howells
@ 2018-11-09 15:28 ` David Howells
1 sibling, 0 replies; 6+ messages in thread
From: David Howells @ 2018-11-09 15:28 UTC (permalink / raw)
To: Mimi Zohar
Cc: dhowells, keyrings, linux-integrity, linux-security-module,
Denis Kenzior
Actually, a better solution would be to set the encoding in the caller, say in
asymmetric_verify() in digsig_asymmetric.c.
David
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2018-11-09 15:29 UTC | newest]
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2018-11-09 5:59 [PATCH] KEYS: revert requiring signature "encoding" Mimi Zohar
2018-11-09 13:16 ` David Howells
2018-11-09 14:14 ` Mimi Zohar
2018-11-09 15:05 ` David Howells
2018-11-09 15:06 ` David Howells
2018-11-09 15:28 ` David Howells
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