OpenPGPCertificate.OpenPGPSignatureChain (Bouncy Castle Library 1.84 API Specification)

java.lang.Object
- org.bouncycastle.openpgp.api.OpenPGPCertificate.OpenPGPSignatureChain

All Implemented Interfaces:

java.lang.Comparable<OpenPGPCertificate.OpenPGPSignatureChain>, java.lang.Iterable<OpenPGPCertificate.OpenPGPSignatureChain.Link>

Enclosing class:

OpenPGPCertificate
```
public static class OpenPGPCertificate.OpenPGPSignatureChain
extends java.lang.Object
implements java.lang.Comparable<OpenPGPCertificate.OpenPGPSignatureChain>, java.lang.Iterable<OpenPGPCertificate.OpenPGPSignatureChain.Link>
```
Chain of signatures. Such a chain originates from a certificates primary key and points towards some certificate component that is bound to a certificate. As for example a subkey can only be bound by a primary key that holds either at least one direct-key self-signature or at least one user-id binding signature, multiple signatures may form a validity chain. Another example is a third-party certification over a user-id or certificates primary key. Here, the chain originates from the certifiers primary key and ends at the user-id or primary key of the signee. An OpenPGPCertificate.OpenPGPSignatureChain can either be a certification (isCertification()), e.g. it represents a positive binding, or it can be a revocation (isRevocation()) which invalidates a positive binding.
Example:
```
                           v-----------\
           [PRIMARY KEY 0xAAAA]         \
            /         \       \         |
           /           \       \__(DIRECT KEY SIG #0)
   (USERID BINDING #1) |
          |    (SUBKEY BINDING #2)
          v           |
  [USERID Alice]      v
                  [SUBKEY 0xAABB]
 
```
Here, the certificates components are bound like follows:
- Primary Key 0xAAAA: [0xAAAA->#0->0xAAAA]
- UserID Alice: [0xAAAA->#0->#1->Alice]
- Subkey 0xAABB: [0xAAAA->#0->#2->0xAABB]
Note: If the certificate does not carry a direct-key self-signature, the primary user-id binding would be used as root link in its place. A binding can also be a revocation. In such case, the whole chain represents a revocation.
In Web-of-Trust scenarios, signature chains can span multiple certificates.
Example:
```
                               ________________
                              v               |
               [PRIMARY KEY 0xAAAA]---(DIRECT KEY SIG #0)
               /         |     \
  (USERID BINDING #1)    |      \
        |                |  (DELEGATION #2)-->[PRIMARY KEY 0xBBBB]
        |                \                            |
        v                 \                  (USERID BINDING #3)
 [USERID Alice]      (CERTIFICATION #4)               |
                             \                        v
                              \________________>[USERID Bob]
 
```
Here, Alice delegated trust to Bob by issuing a direct key delegation signature (#0) over Bobs primary key, as well as a 3rd-party certification signature for UserID Bob. Now there are the following paths of trust from Alice's certificate down to Bobs certificate:
- Bobs Certificate (primary key 0xBBBB): [0xAAAA->#0->#2->0xBBBB
- Bobs UserID Bob: [0xAAAA->#0->#4->Bob
Note, that certificate 0xAAAA holds signatures #0,#1, while certificate 0xBBBB holds signatures #2,#3,#4.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`OpenPGPCertificate.OpenPGPSignatureChain.Certification` "Positive" signature chain link.
`static class`	`OpenPGPCertificate.OpenPGPSignatureChain.Link` Link in a `OpenPGPCertificate.OpenPGPSignatureChain`.
`static class`	`OpenPGPCertificate.OpenPGPSignatureChain.Revocation` "Negative" signature chain link.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`int`	`compareTo(OpenPGPCertificate.OpenPGPSignatureChain other)`
`static OpenPGPCertificate.OpenPGPSignatureChain`	`direct(OpenPGPCertificate.OpenPGPComponentSignature sig)` Factory method for creating an `OpenPGPCertificate.OpenPGPSignatureChain` with only a single link.
`OpenPGPCertificate.OpenPGPSignatureChain.Link`	`getLeafLink()` Return the last link in the chain, which applies to the chains target component.
`OpenPGPCertificate.OpenPGPComponentKey`	`getLeafLinkTargetKey()` Return the `OpenPGPCertificate.OpenPGPComponentKey` to which the leaf link applies to.
`OpenPGPCertificate.OpenPGPComponentSignature`	`getRevocation()` Return the first revocation signature in the chain, or null if the chain does not contain any revocations.
`OpenPGPCertificate.OpenPGPSignatureChain.Link`	`getRootLink()` Return the very first link in the chain.
`OpenPGPCertificate.OpenPGPComponentKey`	`getRootLinkIssuer()` Return the issuer of the root link.
`OpenPGPCertificate.OpenPGPComponentSignature`	`getSignature()` Return the signature from the leaf of the chain, which directly applies to the `OpenPGPCertificate.OpenPGPCertificateComponent`.
`java.util.List<OpenPGPCertificate.OpenPGPComponentSignature>`	`getSignatures()` Return a List of all signatures in the chain.
`java.util.Date`	`getSince()` Return the date since which this signature chain is valid.
`java.util.Date`	`getUntil()` Return the date until which the chain link is valid.
`boolean`	`isCertification()` Return true, if the chain only consists of non-revocation signatures and is therefore a certification chain.
`boolean`	`isEffectiveAt(java.util.Date evaluationDate)` Return true if the chain is effective at the given evaluation date, meaning all link signatures have been created before the evaluation time, and none signature expires before the evaluation time.
`boolean`	`isHardRevocation()` Return true, if the chain contains at least one link that represents a hard revocation.
`boolean`	`isRevocation()` Return true, if the chain contains at least one revocation signature.
`boolean`	`isValid()` Return true if the signature chain is valid, meaning all its chain links are valid.
`boolean`	`isValid(PGPContentVerifierBuilderProvider contentVerifierBuilderProvider, OpenPGPPolicy policy)` Return true if the signature chain is valid, meaning all its chain links are valid.
`java.util.Iterator<OpenPGPCertificate.OpenPGPSignatureChain.Link>`	`iterator()`
`OpenPGPCertificate.OpenPGPSignatureChain`	`plus(OpenPGPCertificate.OpenPGPComponentSignature sig)` Return an NEW instance of the `OpenPGPCertificate.OpenPGPSignatureChain` with the new link appended.
`java.lang.String`	`toString()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.lang.Iterable
forEach, spliterator

- Method Detail
  - getSignature
```
public OpenPGPCertificate.OpenPGPComponentSignature getSignature()
```
    Return the signature from the leaf of the chain, which directly applies to the OpenPGPCertificate.OpenPGPCertificateComponent.
    
    Returns:
    
    signature
  - getRevocation
```
public OpenPGPCertificate.OpenPGPComponentSignature getRevocation()
```
    Return the first revocation signature in the chain, or null if the chain does not contain any revocations.
    
    Returns:
    
    first revocation signature
  - getSignatures
```
public java.util.List<OpenPGPCertificate.OpenPGPComponentSignature> getSignatures()
```
    Return a List of all signatures in the chain.
    
    Returns:
    
    list of signatures
  - plus
```
public OpenPGPCertificate.OpenPGPSignatureChain plus(OpenPGPCertificate.OpenPGPComponentSignature sig)
```
    Return an NEW instance of the OpenPGPCertificate.OpenPGPSignatureChain with the new link appended.
    
    Parameters:
    
    sig - signature
    
    Returns:
    
    new instance
  - direct
```
public static OpenPGPCertificate.OpenPGPSignatureChain direct(OpenPGPCertificate.OpenPGPComponentSignature sig)
```
    Factory method for creating an OpenPGPCertificate.OpenPGPSignatureChain with only a single link.
    
    Parameters:
    
    sig - signature
    
    Returns:
    
    chain
  - getRootLink
```
public OpenPGPCertificate.OpenPGPSignatureChain.Link getRootLink()
```
    Return the very first link in the chain. This is typically a link that originates from the issuing certificates primary key.
    
    Returns:
    
    root link
  - getRootLinkIssuer
```
public OpenPGPCertificate.OpenPGPComponentKey getRootLinkIssuer()
```
    Return the issuer of the root link. This is typically the issuing certificates primary key.
    
    Returns:
    
    root links issuer
  - getLeafLink
```
public OpenPGPCertificate.OpenPGPSignatureChain.Link getLeafLink()
```
    Return the last link in the chain, which applies to the chains target component.
    
    Returns:
    
    leaf link
  - getLeafLinkTargetKey
```
public OpenPGPCertificate.OpenPGPComponentKey getLeafLinkTargetKey()
```
    Return the OpenPGPCertificate.OpenPGPComponentKey to which the leaf link applies to. For subkey binding signatures, this is the subkey. For user-id certification signatures, it is the primary key.
    
    Returns:
    
    target key component of the leaf link
  - isCertification
```
public boolean isCertification()
```
    Return true, if the chain only consists of non-revocation signatures and is therefore a certification chain.
    
    Returns:
    
    true if the chain is a certification, false if it contains a revocation link.
  - isRevocation
```
public boolean isRevocation()
```
    Return true, if the chain contains at least one revocation signature.
    
    Returns:
    
    true if the chain is a revocation.
  - isHardRevocation
```
public boolean isHardRevocation()
```
    Return true, if the chain contains at least one link that represents a hard revocation.
    
    Returns:
    
    true if chain is hard revocation, false if it is a certification or soft revocation
  - getSince
```
public java.util.Date getSince()
```
    Return the date since which this signature chain is valid. This is the creation time of the most recent link in the chain.
    
    Returns:
    
    most recent signature creation time
  - getUntil
```
public java.util.Date getUntil()
```
    Return the date until which the chain link is valid. This is the earliest expiration time of any signature in the chain.
    
    Returns:
    
    earliest expiration time
  - isEffectiveAt
```
public boolean isEffectiveAt(java.util.Date evaluationDate)
```
    Return true if the chain is effective at the given evaluation date, meaning all link signatures have been created before the evaluation time, and none signature expires before the evaluation time.
    
    Parameters:
    
    evaluationDate - reference time
    
    Returns:
    
    true if chain is effective at evaluation date
  - isValid
```
public boolean isValid()
                throws PGPSignatureException
```
    Return true if the signature chain is valid, meaning all its chain links are valid.
    
    Returns:
    
    true if chain is valid
    
    Throws:
    
    PGPSignatureException - if an exception occurs during signature verification
  - isValid
```
public boolean isValid(PGPContentVerifierBuilderProvider contentVerifierBuilderProvider,
                       OpenPGPPolicy policy)
                throws PGPSignatureException
```
    Return true if the signature chain is valid, meaning all its chain links are valid.
    
    Parameters:
    
    contentVerifierBuilderProvider - provider for content verifier builders
    
    policy - algorithm policy
    
    Returns:
    
    true if chain is valid
    
    Throws:
    
    PGPSignatureException - if an exception occurs during signature verification
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object
  - compareTo
```
public int compareTo(OpenPGPCertificate.OpenPGPSignatureChain other)
```
    Specified by:
    
    compareTo in interface java.lang.Comparable<OpenPGPCertificate.OpenPGPSignatureChain>
  - iterator
```
public java.util.Iterator<OpenPGPCertificate.OpenPGPSignatureChain.Link> iterator()
```
    Specified by:
    
    iterator in interface java.lang.Iterable<OpenPGPCertificate.OpenPGPSignatureChain.Link>

Class OpenPGPCertificate.OpenPGPSignatureChain

Nested Class Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.lang.Iterable

Method Detail

getSignature

getRevocation

getSignatures

plus

direct

getRootLink

getRootLinkIssuer

getLeafLink

getLeafLinkTargetKey

isCertification

isRevocation

isHardRevocation

getSince

getUntil

isEffectiveAt

isValid

isValid

toString

compareTo

iterator