I have the need to generate a JWK with the following parameters:
“kty”: Key Type
“kid”: Key ID
“use”: “sig” Public Key Use
“n”: the modulus
“e”: “AQAB” the public exponent
“x5c”: X. 509 Certificate Chain
“x5t”: X.509 Certificate SHA-1 Thumbprint
Note:
JWKs should contain a public key using RSA algorithm. RSA provides a key ID for key
matching purposes.
Should contain X.509 certificate using both “x5t” (X.509 SHA-1 Thumbprint) and “x5c” (X.509
certificate Chain) parameters
The first 5 parameters ("kty", "kid", "use", "n", "e") are fairly straight forward and not an issue. However, for the "x5c" and "x5t" components, I am not sure how to generate these. It seems as I can create an x509 cert using tools such as the one found at https://www.samltool.com/self_signed_certs.php and I suppose the x509 cert generated there would be the x5c parameter. Is this correct and how would I generate a x5t (cert thumbprint) from this?
All help is appreciated.
Since you have neither a tool nor a language tagged, I assume that it is rather a general explanation of both parameters.
In x5c a certificate or certificate chain is stored, in x5t the associated thumbprint. A certificate or certificate chain is used to prove ownership of a public key, the thumbprint is a hash of a certificate used to identify/compare certificates.
The exact definition of both parameters is described in RFC 7517, JSON Web Key (JWK), chapters 4.7 x5c and 4.8 x5t:
x5c:
The "x5c" (X.509 certificate chain) parameter contains a chain of one or more PKIX certificates [RFC5280]. The certificate chain is represented as a JSON array of certificate value strings. Each string in the array is a base64-encoded (Section 4 of [RFC4648] -- not base64url-encoded) DER [ITU.X690.1994] PKIX certificate value. The PKIX certificate containing the key value MUST be the first certificate. This MAY be followed by additional certificates, with each subsequent certificate being the one used to certify the previous one. The key in the first certificate MUST match the public key represented by other members of the JWK. Use of this member is OPTIONAL...
x5t:
The "x5t" (X.509 certificate SHA-1 thumbprint) parameter is a base64url-encoded SHA-1 thumbprint (a.k.a. digest) of the DER encoding of an X.509 certificate [RFC5280]. Note that certificate thumbprints are also sometimes known as certificate fingerprints. The key in the certificate MUST match the public key represented by other members of the JWK. Use of this member is OPTIONAL.
Creation of a certificate:
A self signed certificate can (apart from the online tool you use) also be generated e.g. with OpenSSL. The following OpenSSL statement
openssl req -x509 -newkey rsa:4096 -nodes -keyout key.pem -out cert.crt -days 365
generates a private (unencrypted) PEM encoded 4096 bit key in PKCS#8 format (key.pem):
-----BEGIN PRIVATE KEY-----
MIIJRAIBADANBgkqhkiG9w0BAQEFAASCCS4wggkqAgEAAoICAQDkWIfV9uL3XMay
...
OPAsywknGU1A/xTa3fFKO9KV6t/T9z3G
-----END PRIVATE KEY-----
and a PEM encoded certificate (cert.crt):
-----BEGIN CERTIFICATE-----
MIIF4zCCA8ugAwIBAgIJAKSZ5oC4tblkMA0GCSqGSIb3DQEBCwUAMIGHMQswCQYD
...
6aBMYeKy0dqjtZIlO8rm2Rialc7Qt+0=
-----END CERTIFICATE-----
For more options and details, see openssl req and the post How to generate a self-signed SSL certificate using OpenSSL?.
Note that a self-signed certificate is signed by the owner. Self-signed certificates are used on internal pages or in test environments. A CA-signed certificate, in contrast, is signed by a third-party, publicly trusted certificate authority (CA) like DigiCert or Thawte etc. used e.g. for public-facing websites, s. also here. A signed certificate is requested with a CSR.
Certificates, certificate chains, certificate authorities, etc. are part of a public key infrastructure.
Example use of x5c:
In Appendix B of RFC 7517, an example of the use of the x5c parameter is given. The DER encoded certificate is Base64 encoded and is contained in a JSON array:
{
"kty":"RSA",
"use":"sig",
"kid":"1b94c",
"n":"vrjOfz9Ccdgx5nQudyhdoR17V-IubWMeOZCwX_jj0hgAsz2J_pqYW08
PLbK_PdiVGKPrqzmDIsLI7sA25VEnHU1uCLNwBuUiCO11_-7dYbsr4iJmG0Q
u2j8DsVyT1azpJC_NG84Ty5KKthuCaPod7iI7w0LK9orSMhBEwwZDCxTWq4a
YWAchc8t-emd9qOvWtVMDC2BXksRngh6X5bUYLy6AyHKvj-nUy1wgzjYQDwH
MTplCoLtU-o-8SNnZ1tmRoGE9uJkBLdh5gFENabWnU5m1ZqZPdwS-qo-meMv
VfJb6jJVWRpl2SUtCnYG2C32qvbWbjZ_jBPD5eunqsIo1vQ",
"e":"AQAB",
"x5c":
["MIIDQjCCAiqgAwIBAgIGATz/FuLiMA0GCSqGSIb3DQEBBQUAMGIxCzAJB
gNVBAYTAlVTMQswCQYDVQQIEwJDTzEPMA0GA1UEBxMGRGVudmVyMRwwGgYD
VQQKExNQaW5nIElkZW50aXR5IENvcnAuMRcwFQYDVQQDEw5CcmlhbiBDYW1
wYmVsbDAeFw0xMzAyMjEyMzI5MTVaFw0xODA4MTQyMjI5MTVaMGIxCzAJBg
NVBAYTAlVTMQswCQYDVQQIEwJDTzEPMA0GA1UEBxMGRGVudmVyMRwwGgYDV
QQKExNQaW5nIElkZW50aXR5IENvcnAuMRcwFQYDVQQDEw5CcmlhbiBDYW1w
YmVsbDCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBAL64zn8/QnH
YMeZ0LncoXaEde1fiLm1jHjmQsF/449IYALM9if6amFtPDy2yvz3YlRij66
s5gyLCyO7ANuVRJx1NbgizcAblIgjtdf/u3WG7K+IiZhtELto/A7Fck9Ws6
SQvzRvOE8uSirYbgmj6He4iO8NCyvaK0jIQRMMGQwsU1quGmFgHIXPLfnpn
fajr1rVTAwtgV5LEZ4Iel+W1GC8ugMhyr4/p1MtcIM42EA8BzE6ZQqC7VPq
PvEjZ2dbZkaBhPbiZAS3YeYBRDWm1p1OZtWamT3cEvqqPpnjL1XyW+oyVVk
aZdklLQp2Btgt9qr21m42f4wTw+Xrp6rCKNb0CAwEAATANBgkqhkiG9w0BA
QUFAAOCAQEAh8zGlfSlcI0o3rYDPBB07aXNswb4ECNIKG0CETTUxmXl9KUL
+9gGlqCz5iWLOgWsnrcKcY0vXPG9J1r9AqBNTqNgHq2G03X09266X5CpOe1
zFo+Owb1zxtp3PehFdfQJ610CDLEaS9V9Rqp17hCyybEpOGVwe8fnk+fbEL
2Bo3UPGrpsHzUoaGpDftmWssZkhpBJKVMJyf/RuP2SmmaIzmnw9JiSlYhzo
4tpzd5rFXhjRbg4zW9C+2qok+2+qDM1iJ684gPHMIY8aLWrdgQTxkumGmTq
gawR+N5MDtdPTEQ0XfIBc2cJEUyMTY5MPvACWpkA6SdS4xSvdXK3IVfOWA=="]
}
Note that the line breaks within values are for display purposes only. The DER encoding results from the PEM encoding by removing header, footer and line breaks and Base64 decoding the rest, i.e. the Base64 decoded DER encoded certificate is the body of the PEM encoded certificate without line breaks.
For a certificate chain, the certificates are separated by commas, see e.g. RFC 7515, Appendix B, x5c.
Thumbprint/Fingerprint:
The thumbprint of a certificate is the SHA-1 hash of the DER encoded certificate and can be generated with OpenSSL as follows, s. also here:
openssl x509 -in cert.crt -noout -fingerprint
Here cert.crt is the PEM encoded certificate. For more details, see openssl x509.
Example: If the certificate from RFC 7517, Appendix B is used, the OpenSSL statement returns the following output:
SHA1 Fingerprint=E2:93:5E:9C:40:4B:BF:42:69:2C:87:6E:81:6C:50:90:EB:19:70:AD
i.e. the hex encoded thumbprint is: E2935E9C404BBF42692C876E816C5090EB1970AD or Base64url encoded: 4pNenEBLv0JpLIdugWxQkOsZcK0. The latter is the value of x5t:
"x5t":"4pNenEBLv0JpLIdugWxQkOsZcK0"
Thank you #Topaco for the last comment on your own answer. For anyone still confused, here's a complete flow with sample code:
In a JS environment with Buffer and crypto:
function generateX5t(certificate) {
// Extracts everything between `-----BEGIN CERTIFICATE-----` and `-----END CERTIFICATE-----`
// and remove line-breaks
const data = certificate
.replaceAll('\n', '')
.match(/^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$/gm)
.join('');
const sha1 = crypto.subtle.digest('SHA-1', Buffer.from(data, 'base64'));
const hex = sha1.then((r) => Buffer.from(r).toString('hex'));
const x5t = hex.then((r) => Buffer.from(r, 'hex').toString('base64url'));
return x5t
}
const certificate = `-----BEGIN CERTIFICATE-----
MIIDQjCCAiqgAwIBAgIGATz/FuLiMA0GCSqGSIb3DQEBBQUAMGIxCzAJB
gNVBAYTAlVTMQswCQYDVQQIEwJDTzEPMA0GA1UEBxMGRGVudmVyMRwwGgYD
VQQKExNQaW5nIElkZW50aXR5IENvcnAuMRcwFQYDVQQDEw5CcmlhbiBDYW1
wYmVsbDAeFw0xMzAyMjEyMzI5MTVaFw0xODA4MTQyMjI5MTVaMGIxCzAJBg
NVBAYTAlVTMQswCQYDVQQIEwJDTzEPMA0GA1UEBxMGRGVudmVyMRwwGgYDV
QQKExNQaW5nIElkZW50aXR5IENvcnAuMRcwFQYDVQQDEw5CcmlhbiBDYW1w
YmVsbDCCASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBAL64zn8/QnH
YMeZ0LncoXaEde1fiLm1jHjmQsF/449IYALM9if6amFtPDy2yvz3YlRij66
s5gyLCyO7ANuVRJx1NbgizcAblIgjtdf/u3WG7K+IiZhtELto/A7Fck9Ws6
SQvzRvOE8uSirYbgmj6He4iO8NCyvaK0jIQRMMGQwsU1quGmFgHIXPLfnpn
fajr1rVTAwtgV5LEZ4Iel+W1GC8ugMhyr4/p1MtcIM42EA8BzE6ZQqC7VPq
PvEjZ2dbZkaBhPbiZAS3YeYBRDWm1p1OZtWamT3cEvqqPpnjL1XyW+oyVVk
aZdklLQp2Btgt9qr21m42f4wTw+Xrp6rCKNb0CAwEAATANBgkqhkiG9w0BA
QUFAAOCAQEAh8zGlfSlcI0o3rYDPBB07aXNswb4ECNIKG0CETTUxmXl9KUL
+9gGlqCz5iWLOgWsnrcKcY0vXPG9J1r9AqBNTqNgHq2G03X09266X5CpOe1
zFo+Owb1zxtp3PehFdfQJ610CDLEaS9V9Rqp17hCyybEpOGVwe8fnk+fbEL
2Bo3UPGrpsHzUoaGpDftmWssZkhpBJKVMJyf/RuP2SmmaIzmnw9JiSlYhzo
4tpzd5rFXhjRbg4zW9C+2qok+2+qDM1iJ684gPHMIY8aLWrdgQTxkumGmTq
gawR+N5MDtdPTEQ0XfIBc2cJEUyMTY5MPvACWpkA6SdS4xSvdXK3IVfOWA==
-----END CERTIFICATE-----`
generateX5t(certificate).then(r => console.log(r))
To summarize:
1. Get certificate content between -----BEGIN CERTIFICATE----- and -----END CERTIFICATE-----
2. Remove new lines or line breaks
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
3. Decode the resulting string as Base64
4. SHA1 encode the result
5. HEX decode the result
6. URL-safe Base64 encode the result, this is the value for x5t
I am using Control-M AFT for decryption. The encrypted source file is pulled from Mainframe and while decrypting the file using GnuPG, it fails with below error
gpg: mdc_packet with invalid encoding
gpg: decryption failed: Invalid packet
When trying to decrypt manually, it gives the same error message but the file is decrypted. But from control-m, file is not decrypted and the job fails
I'm trying to automate centos installs via PXE and kickstart with encrypted filesystems. In case we mislay the passphrase we want to use escrow files and encrypt them using the public key attached to an x509 certificate obtained from a web server. The relevant line in the kickstart file is
logvol /home --fstype ext4 --name=lv02 --vgname=vg01 --size=1 --grow --encrypted --escrowcert=http://10.0.2.2:8080/escrow.crt --passphrase=XXXX --backuppassphrase
Leaving the cert as PEM encoded on the web server rather than DER doesn't seem to matter, either work up to a point.
The filesystem is created and encrypted using the supplied passphrase and can be opened on reboot with no issues. Two escrow files are produced as expected and if by using the NSS database containing the private key and the first escrow file I obtain what I think is the passphrase but it doesn't unlock the disk. For example:
# volume_key --secrets -d /tmp/nss e04a93fc-555b-430b-a962-1cdf921e320f-escrow
Data encryption key:<span class="whitespace other" title="Tab">»</span>817E65AC37C1EC802E3663322BFE818D47BDD477678482E78986C25731B343C221CC1D2505EA8D76FBB50C5C5E98B28CAD440349DC0842407B46B8F116E50B34
I assume the string from 817 to B34 is the passphrase but using it in a cryptsetup command does not work.
[root#mypxetest ~]# cryptsetup -v status home
/dev/mapper/home is inactive.
Command failed with code 19.
[root#mypxetest ~]# cryptsetup luksOpen /dev/rootvg01/lv02 home
Enter passphrase for /dev/rootvg01/lv02:
No key available with this passphrase.
Enter passphrase for /dev/rootvg01/lv02:
When prompted I paste in the long numeric string but get the No key available message. However if I use the passphrase specified in the kickstart file or the backup escrow file the disk unlocks.
# volume_key --secrets -d /tmp/nss e04a93fc-555b-430b-a962-1cdf921e320f-escrow-backup-passphrase
Passphrase:<span class="whitespace other" title="Tab">»</span>QII.q-ImgpN-0oy0Y-RC5qa
Then using the string QII.q-ImgpN-0oy0Y-RC5qa in the crypsetup command works.
Has anyone any idea what I'm missing? Why don't both escrow files work?
I've done some more reading and the file ending in escrow is not an alternative passphrase for the luks volume but it contains the encryption key which is encrypted of course. When decrypted the long string is the encryption key and there's a clue in the rest of the text which I confess I didn't read very well.
I try to make a gpg encryption/decryption on my server, for encryption i make this command line :
gpg --output test.txt.gpg --encrypt test.txt
and then i enter a user ID and my file is created.
But after, when i want to decrypt this file with same commande :
gpg --output result.txt --decrypt test.txt.gpg
result is :
gpg: encrypted with 2048-bit RSA key, ID FF070B4D, created 2017-07-19
"droli mail_adress"
gpg: decryption failed: No secret key
i don't understand why i can encrypt but can't decrypt after ?
$gpg --list-keys
/home/ssie/.gnupg/pubring.gpg
-----------------------------
pub 2048R/09C41BAC 2017-07-19
uid droli mail_adress
sub 2048R/6D2F1BE9 2017-07-19
$gpg --list-secret-keys
/home/ssie/.gnupg/secring.gpg
-----------------------------
sec 2048R/09C41BAC 2017-07-19
uid droli mail_adress sub
ssb 2048R/6D2F1BE9 2017-07-19
Edit after 2 hours :
I think to have find why : there were 2 different keys and 1 secret key for the same user. But now there is another issue : i deleted the wrong key and make the same test again.
the answer after decrypt is :
You need a passphrase to unlock the secret key for user: "droli
mail_adress" 2048-bit RSA key, ID 6D2F1BE9, created 2017-07-19 (main
key ID 09C41BAC)
can't connect to `/home/ssie/.gnupg/S.gpg-agent': Connection refused
gpg-agent[32298]: command get_passphrase failed: Operation cancelled
gpg: cancelled by user gpg: encrypted with 2048-bit RSA key, ID
6D2F1BE9, created 2017-07-19 "telefact " gpg: public key decryption
failed: General error gpg: decryption failed: No secret key
what is this "S.gpg-agent" ? (the file /home/ssie/.gnupg/S.gpg-agent is empty in my case)
$ gpg-agent
--daemon GPG_AGENT_INFO=/tmp/gpg-1K7fOi/S.gpg-agent:18607:1; export GPG_AGENT_INFO;
After launching GPG_AGENT_INFO=/tmp/gpg-1K7fOi/S.gpg-agent:18607:1
and export GPG_AGENT_INFO
there is no ask about the gpg agent.
You need a passphrase to unlock the secret key for user: "droli
mail_adress" 2048-bit RSA key, ID 6D2F1BE9, created 2017-07-19 (main
key ID 09C41BAC)
gpg: cancelled by user
gpg: encrypted with 2048-bit RSA key, ID 6D2F1BE9, created 2017-07-19
"droli mail_adress"
gpg: public key decryption failed: General error
gpg: decryption failed: No secret key
When creating a new key i have the same issue at the end :
Change (N)ame, (C)omment, (E)mail or (O)kay/(Q)uit? O
You need a Passphrase to protect your secret key.
gpg: cancelled by user
gpg: Key generation canceled.
it's like there is a dyfonctionnement with the passphrase ?
Thanks for help.
The solution is :
chmod o+rw $(tty)
before using su to become that user and it works as it should.
I need a secret token to be part of a command executed by Travis CI, but am in a public repository. I found that I can encrypt parts of .travis.yml to keep secrets safe. However, encrypting the command like in the following example fails saying Y95MgqDf...Bc=}: No such file or directory
after_deploy:
- secure: "Y95MgqDf...Bc="
You don't encrypt the step. That does not appear to be supported by Travis.
Instead, encrypt only secret part:
$ travis encrypt TOKEN=verysecret
secure: "CnLZ...lI="
Put the secret in an environment variable:
env:
global:
secure: CnLZ...lI=
Then dereference the environment variable when you need your secret.
after_deploy:
- mycommand $TOKEN