p
Registry Context
The "p" parameter contains the first prime factor of an RSA private key represented as a JWK.
Technical Summary
RFC 7518 defines "p" as a Base64urlUInt-encoded first prime factor. For RSA private JWKs, "d" is REQUIRED; optimization parameters such as "p" SHOULD be included; and including any optimization parameter requires all of them except "oth", which is conditional on using more than two prime factors.
When Used
When representing an RSA private key as a JWK.
Normative Requirements
producers of JWKs representing RSA private keys
RFC 7518 - Section 6.3.2
include the "d" parameter.
Condition: when representing an RSA private key
The parameter "d" is REQUIRED for RSA private keys.
RFC 7518 - Section 6.3.2
include the optimization parameters, including "p".
Condition: when representing an RSA private key
The others enable optimizations and SHOULD be included by producers of JWKs representing RSA private keys.
the producer
RFC 7518 - Section 6.3.2
include all other RSA private-key optimization parameters, including "p".
Condition: if any of the other private-key parameters are included, subject to the exception for "oth"
If the producer includes any of the other private key parameters, then all of the others MUST be present, with the exception of "oth".
Validation Guidance
For an RSA private JWK, verify that "d" is present.
If any RSA private-key optimization parameter is present, verify that "p" and all other optimization parameters are present, except that "oth" is conditional.
For producers of RSA private JWKs, prefer including "p" as part of the optimization parameter set.
Verify that "p" is represented as a Base64urlUInt-encoded value.
Reference
Details
- Entry Id
p- Parameter Name
p- Parameter Description
First Prime Factor- Used With Kty Value
RSA- Parameter Information Class
Private- Change Controller
IESG- Reference
RFC7518 - Section 6.3.2.2