From f7ea1b115e60bb1e3592e20d27fbcef46551a416 Mon Sep 17 00:00:00 2001 From: "Tammi L. Coles" Date: Fri, 10 Nov 2023 17:45:36 +0100 Subject: [PATCH] edit ch7 ## Signature types --- book/source/07-signing_data.md | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/book/source/07-signing_data.md b/book/source/07-signing_data.md index adbf0db..8f3bdfa 100644 --- a/book/source/07-signing_data.md +++ b/book/source/07-signing_data.md @@ -19,15 +19,14 @@ Note that signatures over data are distinct from {ref}`component_signatures_chap ## Signature types -Data signatures use one of two OpenPGP [signature types](signature_types): +OpenPGP data signatures use one of two [signature types](signature_types): -- "Signature of a binary document" (*Binary Signature*, type ID `0x00`): A universal signature type for binary data. Binary signatures are typically used for files or data streams. -Binary signatures are calculated over the data "as is", without performing any transformations. -- "Signature of a canonical text document" (*Text Signature*, type ID `0x01`): Used for textual data, such as email bodies. When calculating a text signature, the data is first normalized by converting line endings into a canonical form (``). The normalization mitigates issues caused by platform-specific text encodings, for example with detached signatures, where the message file may get re-encoded between signature generation and validation. +- **Binary signature** (type ID `0x00`): This is the standard signature type for binary data and is typically used for files or data streams. Binary signatures are calculated over the data without any modifications or transformations. +- **Text signature** (type ID `0x01`): Used for textual data, such as email bodies. When calculating a text signature, the data is first normalized by converting line endings into a canonical form (``). This mitigates issues caused by platform-specific text encodings, which is particularly important for detached signatures where the message file might be re-encoded between signature creation and verification. -Data signatures are generated by hashing the message content, plus the metadata in the signature packet, and calculating a cryptographic signature over that hash. The resulting cryptographic signature is stored in an OpenPGP signature packet. +Data signatures are generated by hashing the message content along with the metadata in the signature packet, and calculating a cryptographic signature over that hash. The resulting cryptographic signature is stored in an OpenPGP signature packet. -Data signature packets can be used in three different forms. We'll discuss these in the following section. +Data signature packets manifest in three distinct forms, which will be detailed in the subsequent section. ## Forms of OpenPGP data signatures