<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"></head><body dir="auto"><div dir="auto">Thanks for the hint. Without searching the Web just yet in between two calls, do you happen to know of any option for Windows users? </div><div dir="auto"><br></div><div dir="auto"><br></div><div dir="auto">Regards </div><div dir="auto"><br></div><div dir="auto">-- </div><div dir="auto">Alexander Kriegisch</div><div dir="auto"><br></div><div dir="auto"><br></div><div><br></div><div align="left" dir="auto" style="font-size:100%;color:#000000"><div>-------- Ursprüngliche Nachricht --------</div><div>Von: Andrew Gallagher <andrewg@andrewg.com> </div><div>Datum: 20.12.20 17:11 (GMT+07:00) </div><div>An: Alexander Kriegisch <alexander@kriegisch.name> </div><div>Cc: gnupg-users@gnupg.org </div><div>Betreff: Re: Split private key in order to share among users </div><div><br></div></div><br>> On 20 Dec 2020, at 09:19, Alexander Kriegisch <alexander@kriegisch.name> wrote:<br>> <br>> The original PGP used to have this feature around 20 years ago already,<br>> maybe some people remember. In the list archive I found two threads,<br>> both several years old, asking about this feature in GnuPG, but there<br>> were no conclusive answers, only workaround suggestions like to split<br>> the binary or ASCII key file or print the password and share parts of<br>> the passwords, neither of which satisfy the original requirements<br>> covered by the original PGP functionality. Example:<br>> <br>> I split a private key file with PGP into these shares:<br>> -- User A gets a piece of key worth 2 shares.<br>> -- User B gets a piece of key worth 2 shares.<br>> -- User C gets a piece of key worth 1 share.<br>> -- User D gets a piece of key worth 1 share.<br>> -- User E gets a piece of key worth 1 share.<br>> -- User F gets a piece of key worth 1 share.<br>> <br>> I define that at least 5 shares are necessary to re-assemble a valid<br>> decryption key, i.e. we need for example<br>> -- A + B + one other user<br>> -- C + D + E + either A or B<br>> for decryption.<br>> <br><br>You’re referring to Shamir’s secret sharing scheme, for which several implementations exist. If you are using Linux, it should be as simple as installing the “ssss” package. <br><br>A<br></body></html>