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+# Enum Definitions
+
+## Crypto.Mode
+:egg::egg::egg:
+* Type: number
+
+Name | Value | Description
+--- | --- | ---
+RC4_40 | 0 | 40bit RC4 Encryption
+RC4_128 | 1 | 128bit RC4 Encryption
+AES_128 | 2 | 128bit AES Encryption
+AES_256 | 3 | 256bit AES Encryption
+
+# Type Definitions
+
+## DSSInfo
+:taco::taco::taco:
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+certs | Array\<forge_cert\> | optional | An array of necessary certificates.
+ocsps | Array\<Uint8Array\> | optional | An array of [OCSP](#note)s' response.
+crls | Array\<Uint8Array\> | optional | The array of [CRL](#note)s.
+
+## EncryptOption
+:taco::taco::taco:
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+mode | [Crypto.Mode](#Crypto.Mode) | required | The mode of encryption
+permissions | Array\<string\> | optional | The set of permissions to be blocked :one:
+userpwd | string | optional | User password. Used when opening the pdf.
+ownerpwd | string | optional | Owner password. If not specified, a random value is used.
+pubkeys | Array\<[PubKeyInfo](#PubKeyInfo)\> | optional | An array of recipients containing public-key certificates ('c') and permissions ('p').
+
+:one: `permissions` can be the values listed blow.
+  * `copy`: (Only valid on public-key mode) Copy text and graphics from the document;
+  * `print`: Print the document;
+  * `modify`: Modify the contents of the document by operations other than those controlled by 'fill-forms', 'extract' and 'assemble';
+  * `copy-extract`: Copy or otherwise extract text and graphics from the document;
+  * `annot-forms`: Add or modify text annotations, fill in interactive form fields, and, if 'modify' is also set, create or modify interactive form fields (including signature fields);
+  * `fill-forms`: Fill in existing interactive form fields (including signature fields), even if 'annot-forms' is not specified;
+  * `extract`: Extract text and graphics (in support of accessibility to users with disabilities or for other purposes);
+  * `assemble`: Assemble the document (insert, rotate, or delete pages and create bookmarks or thumbnail images), even if 'modify' is not set;
+  * `print-high`: Print the document to a representation from which a faithful digital copy of the PDF content could be generated. When this is not set, printing is limited to a low-level representation of the appearance, possibly of degraded quality.
+
+
+## PubKeyInfo
+:taco::taco::taco:
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+c | Array\<number\><br />:fork_and_knife:Uint8Array<br />:fork_and_knife:ArrayBuffer<br />:fork_and_knife:string<br />:fork_and_knife:forge_cert | optional | A certificate.
+p | Array\<string\> | optional | An array of permissions you want to block. Valid values see [EncryptOption](#encryptoption)
+
+## SignAreaInfo
+:taco::taco::taco:
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+x | number | required | Distance from left
+y | number | required | Distance from top
+w | number | required | Width
+h | number | required | Height
+
+## SignDrawInfo
+:taco::taco::taco:
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+area | [SignAreaInfo](#signareainfo) | required | The signature's drawing area, these numbers are dots on 72dpi.
+pageidx | number | optional | The index of a page where the signature will be drawn. Default is 0.
+imgData | Array\<number\><br />:fork_and_knife:Uint8Array<br />:fork_and_knife:ArrayBuffer<br />:fork_and_knife:string | optional | The image's data.
+imgType | string | optional | The image's type, <ins>only support jpg and png</ins>
+text | string| optional | A text drawing for the signature, <ins>not implemented yet</ins>
+fontData | PDFLib.StandardFonts<br />:fork_and_knife:Array\<number\><br />:fork_and_knife:Uint8Array<br />:fork_and_knife:ArrayBuffer<br />:fork_and_knife:string | optional | The font's data for drawing text, <ins>not implemented yet</ins>
+
+## SignOption
+:taco::taco::taco:
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+p12cert | Array\<number\><br />:fork_and_knife:Uint8Array<br />:fork_and_knife:ArrayBuffer<br />:fork_and_knife:string | optional | Certificate's data. In the case of adding a document timestamp, it must be omitted.
+pwd | string | optional | The passphrase of the certificate. In the case of adding a document timestamp, it must be omitted.
+permission | number | optional | The modification permissions granted for this document. :one:
+reason | string | optional | The reason for signing
+location | string | optional | Your location
+contact | string | optional | Your contact information
+signdate | [TsaServiceInfo](#tsaserviceinfo)<br />:fork_and_knife:string<br />:fork_and_knife:Date | optional | In the case of adding a document timestamp, it can't be omitted and can't be a Date. :two:
+signame | string | optional | The name of the signature
+drawinf | [SignDrawInfo](#SignDrawInfo) | optional | Visible signature's information
+ltv | number | optional | The method of how to enable [LTV](#note) :three:
+debug | boolean | optional | To output debug informations or not
+
+:one: `permission` is a setting of [DocMDP](#note). Valid values are:
+  * 1: No changes to the document are permitted; any change to the document invalidates the signature.
+  * 2: Permitted changes are filling in forms, instantiating page templates, and signing; other changes invalidate the signature.
+  * 3: Permitted changes are the same as for 2, as well as annotation creation, deletion, and modification; other changes invalidate the signature.
+
+:two: `signdate`
+  * When it is a Date, it means the date and time of signing.
+  * When it is a string, it can be an url of [TSA](#note) or an index of the preset [TSA](#note)s as below:
+    * "1": http://ts.ssl.com
+    * "2": http://timestamp.digicert.com
+    * "3": http://timestamp.sectigo.com
+    * "4": http://timestamp.entrust.net/TSS/RFC3161sha2TS
+    * "5": http://timestamp.apple.com/ts01
+    * "6": http://www.langedge.jp/tsa
+    * "7": https://freetsa.org/tsr
+  * When it is a [TsaServiceInfo](#TsaServiceInfo), it means a full customized information of a [TSA](#note).
+  * When it is omitted, the system timestamp will be used.
+
+:three: `ltv`'s valid values are:
+  * 1: auto; Try using [OCSP](#note) only to enable the [LTV](#note) first; If can't, try using [CRL](#note) to enable the [LTV](#note).
+  * 2: crl only; Only try using [CRL](#note) to enable the [LTV](#note).
+
+
+## TsaServiceInfo
+:taco::taco::taco:
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+url | string | required | The url of [TSA](#note).
+len | number | optional | The length of signature's placeholder.
+headers | Object\<string, *\> | optional | The customized headers for sending to tsa server.
+
+# Function Definitions
+
+## u8arrToRaw
+:fondue::fondue::fondue:
+#### u8arrToRaw(uarr) :arrow_right: string
+Converts an Uint8Array to a raw string.
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+uarr | Uint8Array | required | The target Uint8Array
+
+## rawToU8arr
+:fondue::fondue::fondue:
+#### rawToU8arr(raw) :arrow_right: Uint8Array
+Converts a raw string to an Uint8Array.
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+raw | string | required | The target string
+
+# Classes
+
+## CertsChain
+:croissant::croissant::croissant:
+### Constructor
+#### new CertsChain(certs<sub>*opt*</sub>)
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+certs | Array\<forge_cert\><br />:fork_and_knife:Array\<forge.asn1\><br />:fork_and_knife:Array\<string\> | optional | An array of certificates.
+
+### Methods
+#### buildChain(cert) :arrow_right: Promise\<boolean\>
+Build the certificates chain from the specified certificate, and returns true if this operation is successful.
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+cert | forge_cert | required | A certificate to start build by looking for it's issuer.
+
+#### getAllCerts() :arrow_right: Array\<forge_cert\>
+Returns an array of all certificates.
+
+#### getSignCert() :arrow_right: forge_cert
+Returns the certificate for signing.
+
+#### isSelfSignedCert() :arrow_right: boolean
+Returns true if the certificate for signing is a self-signed certificate.
+
+#### prepareDSSInf(crlOnly<sub>*opt*</sub>) :arrow_right: Promise\<[DSSInfo](#dssinfo)\>
+Returns the informations of [DSS](#note).
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+crlOnly | boolean | optional | Query [CRL](#note) only or try query [OCSP](#note) first.
+
+## PdfCryptor
+:croissant::croissant::croissant:
+### Constructor
+#### new PdfCryptor(encopt)
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+encopt | [EncryptOption](#EncryptOption) | required | Infomations of encryption.
+
+### Methods
+#### encryptObject(num, val)
+Encrypts the content of the specified pdf object.
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+num | number | required | The object number.
+val | PDFLib.PDFObject | required | The target object.
+
+#### encryptPdf(pdf, ref<sub>*opt*</sub>) :arrow_right: Promise\<PDFLib.PDFDocument\>
+Encrypts the contents in the pdf and returns the pdf document.
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+pdf | PDFLib.PDFDocument<br />:fork_and_knife:Array\<number\><br />:fork_and_knife:Uint8Array<br />:fork_and_knife:ArrayBuffer<br />:fork_and_knife:string | required | The target pdf.
+ref | PDFLib.PDFRef | optional | The unique reference will be assigned to the encryption information.
+
+## PdfSigner
+:croissant::croissant::croissant:
+### Constructor
+#### new PdfSigner(signopt)
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+signopt | [SignOption](#SignOption) | required | Infomations of signing.
+
+### Methods
+#### sign(pdf, cypopt<sub>*opt*</sub>) :arrow_right: Promise\<Uint8Array\>
+Sign the pdf and returns the binary data.
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+pdf | PDFLib.PDFDocument|Array\<number\>|Uint8Array|ArrayBuffer|string | required | The target pdf.
+cypopt | [EncryptOption](#EncryptOption) | optional | The informations of encryption.
+
+## TsaFetcher
+:croissant::croissant::croissant:
+### Constructor
+#### new TsaFetcher(inf)
+
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+inf | [TsaServiceInfo](#TsaServiceInfo) | required | Infomations of [TSA](#note).
+
+### Properties
+
+Name | Type | Description
+--- | --- | ---
+url | string | The url of [TSA](#note).
+len | number | The length of signature which is generated by the [TSA](#note).
+
+### Methods
+#### getCertsChain() :arrow_right: [CertsChain](#CertsChain)
+Get the certificates' chain from the response of [TSA](#note).
+
+#### getToken(forP7<sub>*opt*</sub>) :arrow_right: forge.asn1
+Get the token data in response from [TSA](#note).
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+forP7 | boolean | optional | To create an asn1 for appending to a pkcs#7 signature or not.
+
+#### queryTsa(data) :arrow_right: Promise\<string\>
+Query [TSA](#note) to sign the data and returns error message if error occured.
+Name | Type | Attributes | Description
+--- | --- | --- | ---
+data | string | required | The data needs to be signed.
+
+## Note
+1. __CRL__:loudspeaker: Certificate Revocation List
+2. __DDS__:loudspeaker: Document Security Store
+3. __DocMDP__:loudspeaker: Document Modification Detection and Prevention
+4. __LTV__:loudspeaker: Long-Term Validation
+5. __OCSP__:loudspeaker: Online Certificate Status Protocol
+6. __TSA__:loudspeaker: Time Stamp Authority