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4.2. The Signature HTTP Field

4.2. The Signature HTTP Field

The Signature field is a Dictionary Structured Field (defined in Section 3.2 of [STRUCTURED-FIELDS]) containing one or more message signatures generated from the signature context of the target message. The member's key is the label that uniquely identifies the message signature within the HTTP message. The member's value is a Byte Sequence containing the signature value for the message signature identified by the label:

NOTE: '' line wrapping per RFC 8792

Signature: sig1=:P0wLUszWQjoi54udOtydf9IWTfNhy+r53jGFj9XZuP4uKwxyJo
1RSHi+oEF1FuX6O29d+lbxwwBao1BAgadijW+7O/PyezlTnqAOVPWx9GlyntiCiHz
C87qmSQjvu1CFyFuWSjdGa3qLYYlNm7pVaJFalQiKWnUaqfT4LyttaXyoyZW84jS8
gyarxAiWI97mPXU+OVM64+HVBHmnEsS+lTeIsEQo36T3NFf2CujWARPQg53r58Rmp
Z+J9eKR2CD6IJQvacn5A4Ix5BUAVGqlyp8JYm+S/CWJi31PNUjRRCusCVRj05NrxA
BNFv3r5S9IXf2fYJK+eyW4AiGVMvMcOg==:

The signer MAY include the Signature field as a trailer to facilitate signing a message after its content has been processed by the signer. However, since intermediaries are allowed to drop trailers as per [HTTP], it is RECOMMENDED that the Signature field be included only as a header field to avoid signatures being inadvertently stripped from a message.

Multiple Signature fields MAY be included in a single HTTP message. The signature labels MUST be unique across all field values.