This question already has an answer here:
- One Encryption, Many Decryption Keys 7 answers
Is there a asymmetric encryption scheme that allows for multiple private decryption keys?
where m= plaintext message and c= cyphertext message
c = Ek(m) where K is the public encryption key.
m = Dj(c) where J is the private decryption key.
nothing out of the ordinary here, RSA satisfies this basic scenario.
In addition I also want the message to be decrypted by any number of additional keys, ( Dj1 ... Djn ) such that:
m = Djn(c)
does such a scheme exist?
note: I am NOT referring to the way GPG/PGP broadcasts a message to many parties.
edit: looks to be similar to One Encryption, Many Decryption Keys
in particular see D.W.'s answer https://crypto.stackexchange.com/a/39403/29315