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Shift away from "plaintext" term for the signed data

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Talking about "plaintext" seems potentially confusing, especially when signing an encrypted message.
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Heiko Schaefer 2023-12-20 15:20:21 +01:00
parent ad68dc83da
commit 7d756c77ee
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GPG key ID: DAE9A9050FCCF1EB
1 changed files with 3 additions and 3 deletions
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book/source/signing_data.md
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@ -35,7 +35,7 @@ Note that {term}`data signatures<Data Signature>` are distinct from [](/signing_
- **{term}`Detached<Detached Signature>`**: The OpenPGP signature exists as a separate entity, independent of the signed data.
- **{term}`Inline<Inline Signature>`**: Both the original data and its corresponding {term}`OpenPGP signature<OpenPGP Signature Packet>` are encapsulated within an {term}`OpenPGP message`.
- **{term}`Cleartext signature`**: A plaintext message and its {term}`OpenPGP signature<OpenPGP Signature Packet>` coexist in a combined text format, preserving the readability of the original message.
- **{term}`Cleartext signature`**: A plain text message and its {term}`OpenPGP signature<OpenPGP Signature Packet>` coexist in a combined text format, preserving the readability of the original message.
[^sign-modes-gpg]: These three forms of {term}`signature<OpenPGP Signature Packet>` application align with GnuPG's `--detach-sign`, `--sign`, and `--clearsign` command options.
@ -89,7 +89,7 @@ Instead, it's a type of auxiliary packet that can be used in conjunction with {t
#### The function of the one-pass signature packet
To understand the purpose of this packet, consider that without it, the position of signature packets within an inline signed OpenPGP message constitutes a trade-off for efficient data processing. In particular when plaintext data is large and exceeds available memory in size.
To understand the purpose of this packet, consider that without it, the position of signature packets within an inline signed OpenPGP message constitutes a trade-off for efficient data processing. In particular when signed data is large and exceeds available memory in size.
The producer of a signed OpenPGP message wants to streamline the signature calculation process in such a way that allows to emit a copy of the signed data while calculating the cryptographic signature. On the signer's side, the signature packet is therefore easy to store after the signed data.
@ -109,7 +109,7 @@ The signer can easily emit this metadata before processing the full message, and
#### Creation
To produce an {term}`inline signature`, the {term}`signer` decides on a hash algorithm and emits a {term}`one-pass signature packet<One-pass Signature Packet>` into the destination {term}`OpenPGP message`. This contains essential information such as the {term}`fingerprint<OpenPGP Fingerprint>` of the {term}`signing key<OpenPGP Component Key>` and the {term}`hash<Hash Digest>` algorithm used for computing the {term}`signature<OpenPGP Signature Packet>`'s {term}`hash digest`. The signer then processes the entirety of the plaintext data, emitting it as a {term}`literal data<Literal Data Packet>` into the message as well. Once the data is processed, the {term}`signer` calculates a {term}`cryptographic signature` using the calculated hash value. Lastly, the result is emitted as a {term}`data signature packet` to the output message, and the whole packet sequence can be efficiently stored or transmitted.
To produce a {term}`one-pass inline signature<One-pass signed Message>`, the {term}`signer` decides on a hash algorithm and emits a {term}`one-pass signature packet<One-pass Signature Packet>` into the destination {term}`OpenPGP message`. This contains essential information such as the {term}`fingerprint<OpenPGP Fingerprint>` of the {term}`signing key<OpenPGP Component Key>` and the {term}`hash<Hash Digest>` algorithm used for computing the {term}`signature<OpenPGP Signature Packet>`'s {term}`hash digest`. The signer then processes the entirety of the signed data, emitting it as a {term}`literal data<Literal Data Packet>` into the message as well. Once the data is processed, the {term}`signer` calculates a {term}`cryptographic signature` using the calculated hash value. Lastly, the result is emitted as a {term}`data signature packet` to the output message, and the whole packet sequence can be efficiently stored or transmitted.
For efficient {term}`verification`, an application must understand how to handle the {term}`literal data<Literal Data Packet>` prior to reading from it. This requirement is addressed by the {term}`one-pass signature packets<One-pass Signature Packet>` located at the beginning of {term}`inline-signed<Inline Signature>` messages. This setup enables the verifier to process the data correctly and efficiently in only a single pass.