When I decrypt a file in OpenPGP (in Golang), I receive this error message:
unsupported feature: nested signatures
There is very little clear information about this kind of signature.
In RFC 4880, under One-Pass Signature Packets, it says that:
The body of this packet consists of:
- A one-octet version number. The current version is 3.
- A one-octet signature type. Signature types are described in Section 5.2.1.
A one-octet number describing the hash algorithm used.
A one-octet number describing the public-key algorithm used.
- An eight-octet number holding the Key ID of the signing key.
A one-octet number holding a flag showing whether the signature is nested. A zero value indicates that the next packet is another One-Pass Signature packet that describes another signature to be applied to the same message data.
Note that if a message contains more than one one-pass signature,
then the Signature packets bracket the message; that is, the first
Signature packet after the message corresponds to the last one-pass
packet and the final Signature packet corresponds to the first
However, I simply can't understand what "bracket the message" means. Could someone explain it more clearly? Thanks.