Re: [PATCH v9 2/9] x509: Detect sm2 keys by their parameters OID

[Stefan Berger]

On 3/5/21 2:37 AM, Tianjia Zhang wrote:
> Hi,
>
> On 3/4/21 7:46 AM, Stefan Berger wrote:
> > Tianjia,
> >
> >     can you say whether SM2 support works for you before and after 
> > applying this patch? I cannot verify it with an sm2 key I have 
> > created using a sequence of commands like this:
> >
> >  > modprobe sm2_generic
> >  > id=$(keyctl newring test @u)
> >  > keyctl padd asymmetric "" $id < sm2.der
> > add_key: Key was rejected by service
> >  > keyctl padd asymmetric "" $id < eckeys/cert-prime192v1-0.der
> > 88506426
> >
> > The sm2 key is reject but the pime192v1 key works just fine. SM2 
> > support neither worked for me before nor after this patch here. The 
> > difference is that before it returned 'add_key: Package not installed'.
> >
> > This is my sm2 cert:
> >
> >  > base64 < sm2.der
> > MIIBbzCCARWgAwIBAgIUfqwndeAy7reymWLwvCHOgYPU2YUwCgYIKoZIzj0EAwIwDTELMAkGA1UE 
> >
> > AwwCbWUwHhcNMjEwMTI0MTgwNjQ3WhcNMjIwMTI0MTgwNjQ3WjANMQswCQYDVQQDDAJtZTBZMBMG 
> >
> > ByqGSM49AgEGCCqBHM9VAYItA0IABEtiMaczdk46MEugmOsY/u+puf5qoi7JdLd/w3VpdixvDd26 
> >
> > vrxLKL7lCTVn5w3a07G7QB1dgdMDpzIRgWrVXC6jUzBRMB0GA1UdDgQWBBSxOVnE7ihvTb6Nczb4 
> >
> > /mow+HIc9TAfBgNVHSMEGDAWgBSxOVnE7ihvTb6Nczb4/mow+HIc9TAPBgNVHRMBAf8EBTADAQH/ 
> >
> > MAoGCCqGSM49BAMCA0gAMEUCIE1kiji2ABUy663NANe0iCPjCeeqg02Yk4b3K+Ci/Qh4AiEA/cFB 
> >
> > eJEVklyveRMvuTP7BN7FG4U8iRdtedjiX+YrNio=
> >
> > Regards,
> >     Stefan
>
> Yes, it works fine here. Your test method may be wrong. First of all, 
> the certificate looks wrong, I don’t know if it is not sent 
> completely. Secondly, the SM2 algorithm must be compiled with builtin. 
> There will be a problem when it is compiled into a module. This is a 
> restriction for SM2 signature with Za. you may refer to this discussion:
>
> https://lkml.org/lkml/2021/1/12/1736
>
> In addition, give you a self-signed root certificate for my test:
>
> -----BEGIN CERTIFICATE-----
> MIICLjCCAdWgAwIBAgIUEoozP6LzMYWh4gCpcWlzsUyfgsIwCgYIKoEcz1UBg3Uw
> bTELMAkGA1UEBhMCQ04xCzAJBgNVBAgMAkdTMQswCQYDVQQHDAJHdDENMAsGA1UE
> CgwEYmFiYTELMAkGA1UECwwCT1MxCzAJBgNVBAMMAmNhMRswGQYJKoZIhvcNAQkB
> FgxjYUB3b3JsZC5jb20wHhcNMjAwNDE1MTE1NDA3WhcNMzAwNDEzMTE1NDA3WjBt
> MQswCQYDVQQGEwJDTjELMAkGA1UECAwCR1MxCzAJBgNVBAcMAkd0MQ0wCwYDVQQK
> DARiYWJhMQswCQYDVQQLDAJPUzELMAkGA1UEAwwCY2ExGzAZBgkqhkiG9w0BCQEW
> DGNhQHdvcmxkLmNvbTBZMBMGByqGSM49AgEGCCqBHM9VAYItA0IABMTGRiHezKm5
> MiKHlyfa5Bv5jLxge/WRRG0nLNsZx1yf0XQTQBR/tFFjPGePEr7+Fa1CPgYpXExx
> i44coYMmQT6jUzBRMB0GA1UdDgQWBBSjd9GWIe98Ll9J0dquxgCktp9DrTAfBgNV
> HSMEGDAWgBSjd9GWIe98Ll9J0dquxgCktp9DrTAPBgNVHRMBAf8EBTADAQH/MAoG
> CCqBHM9VAYN1A0cAMEQCIAvLWIfGFq85u/vVMLc5H1D/DnrNS0VhSkQA4daRO4tc
> AiABbeWENcQZDZLWTuqG9P2KDPOoNqV/QV/+0XjMAVblhg==
> -----END CERTIFICATE-----
>
> If you can, please add:
>
> Tested-by: Tianjia Zhang <tianjia.zhang@xxxxxxxxxxxxxxxxx>
>
> good luck!


It works with your certificate! When I create the sm2 with OpenSSL on 
Ubuntu, which seems to have sm2 support, or so one may think, I get this 
type of signature:


I cannot create it with sm3, if that's how this is supposed to be signed:

> # openssl req -x509 -sm3 -newkey ec -pkeyopt ec_paramgen_curve:sm2 
-keyout sm2key.pem -days 365 -subj '/CN=test' -nodes -outform der -out 
sm2.der
parameter error "ec_paramgen_curve:sm2"
140735899258064:error:100AE081:elliptic curve 
routines:EC_GROUP_new_by_curve_name:unknown group:crypto/ec/ec_curve.c:418:
140735899258064:error:100C508D:elliptic curve 
routines:pkey_ec_ctrl:invalid curve:crypto/ec/ec_pmeth.c:231:


Using sha256 instead, which is the mistake:

> openssl req -x509 -sha256 -newkey ec -pkeyopt ec_paramgen_curve:sm2 
-keyout sm2key.pem -days 365 -subj '/CN=test' -nodes -outform der -out 
sm2-2nd.der

> openssl x509 -inform der -in sm2-2nd.der -noout -text

[...]

    Signature Algorithm: ecdsa-with-SHA256
         30:45:02:20:05:72:15:b0:e8:f5:5a:27:d2:fb:f9:de:de:35:
         05:b2:76:8a:6f:84:c1:54:db:c2:38:8c:d2:64:8b:67:23:01:
         02:21:00:97:77:9e:42:fa:41:3d:d4:81:5e:5b:ad:9e:56:ad:
         46:fc:5e:94:92:a6:07:2d:af:62:d2:2d:39:7b:71:f1:4a


Yours has this type of signature:

    Signature Algorithm: 1.2.156.10197.1.501
         30:44:02:20:0b:cb:58:87:c6:16:af:39:bb:fb:d5:30:b7:39:
         1f:50:ff:0e:7a:cd:4b:45:61:4a:44:00:e1:d6:91:3b:8b:5c:
         02:20:01:6d:e5:84:35:c4:19:0d:92:d6:4e:ea:86:f4:fd:8a:
         0c:f3:a8:36:a5:7f:41:5f:fe:d1:78:cc:01:56:e5:86

Thanks anyway!


   Stefan