TlsDatabase

Added in version 2.30.

class TlsDatabase(**properties: Any)

Superclasses: Object

GTlsDatabase is used to look up certificates and other information from a certificate or key store. It is an abstract base class which TLS library specific subtypes override.

A GTlsDatabase may be accessed from multiple threads by the TLS backend. All implementations are required to be fully thread-safe.

Most common client applications will not directly interact with GTlsDatabase. It is used internally by TlsConnection.

Methods

class TlsDatabase
create_certificate_handle(certificate: TlsCertificate) → str | None

Create a handle string for the certificate. The database will only be able to create a handle for certificates that originate from the database. In cases where the database cannot create a handle for a certificate, None will be returned.

This handle should be stable across various instances of the application, and between applications. If a certificate is modified in the database, then it is not guaranteed that this handle will continue to point to it.

Added in version 2.30.

Parameters:

certificate – certificate for which to create a handle.

lookup_certificate_for_handle(handle: str, interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None) → TlsCertificate | None

Look up a certificate by its handle.

The handle should have been created by calling create_certificate_handle() on a TlsDatabase object of the same TLS backend. The handle is designed to remain valid across instantiations of the database.

If the handle is no longer valid, or does not point to a certificate in this database, then None will be returned.

This function can block, use lookup_certificate_for_handle_async() to perform the lookup operation asynchronously.

Added in version 2.30.

Parameters:

  • handle – a certificate handle

  • interaction – used to interact with the user if necessary

  • flags – Flags which affect the lookup.

  • cancellable – a Cancellable, or None

lookup_certificate_for_handle_async(handle: str, interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

Asynchronously look up a certificate by its handle in the database. See lookup_certificate_for_handle() for more information.

Added in version 2.30.

Parameters:

  • handle – a certificate handle

  • interaction – used to interact with the user if necessary

  • flags – Flags which affect the lookup.

  • cancellable – a Cancellable, or None

  • callback – callback to call when the operation completes

  • user_data – the data to pass to the callback function

lookup_certificate_for_handle_finish(result: AsyncResult) → TlsCertificate

Finish an asynchronous lookup of a certificate by its handle. See lookup_certificate_for_handle() for more information.

If the handle is no longer valid, or does not point to a certificate in this database, then None will be returned.

Added in version 2.30.

Parameters:

result – a AsyncResult.

lookup_certificate_issuer(certificate: TlsCertificate, interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None) → TlsCertificate

Look up the issuer of certificate in the database. The TlsCertificate:issuer property of certificate is not modified, and the two certificates are not hooked into a chain.

This function can block. Use lookup_certificate_issuer_async() to perform the lookup operation asynchronously.

Beware this function cannot be used to build certification paths. The issuer certificate returned by this function may not be the same as the certificate that would actually be used to construct a valid certification path during certificate verification. RFC 4158 explains why an issuer certificate cannot be naively assumed to be part of the the certification path (though GLib’s TLS backends may not follow the path building strategies outlined in this RFC). Due to the complexity of certification path building, GLib does not provide any way to know which certification path will actually be used when verifying a TLS certificate. Accordingly, this function cannot be used to make security-related decisions. Only GLib itself should make security decisions about TLS certificates.

Added in version 2.30.

Parameters:

  • certificate – a TlsCertificate

  • interaction – used to interact with the user if necessary

  • flags – flags which affect the lookup operation

  • cancellable – a Cancellable, or None

lookup_certificate_issuer_async(certificate: TlsCertificate, interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

Asynchronously look up the issuer of certificate in the database. See lookup_certificate_issuer() for more information.

Added in version 2.30.

Parameters:

  • certificate – a TlsCertificate

  • interaction – used to interact with the user if necessary

  • flags – flags which affect the lookup operation

  • cancellable – a Cancellable, or None

  • callback – callback to call when the operation completes

  • user_data – the data to pass to the callback function

lookup_certificate_issuer_finish(result: AsyncResult) → TlsCertificate

Finish an asynchronous lookup issuer operation. See lookup_certificate_issuer() for more information.

Added in version 2.30.

Parameters:

result – a AsyncResult.

lookup_certificates_issued_by(issuer_raw_dn: Sequence[int], interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None) → list[TlsCertificate]

Look up certificates issued by this issuer in the database.

This function can block, use lookup_certificates_issued_by_async() to perform the lookup operation asynchronously.

Added in version 2.30.

Parameters:

  • issuer_raw_dn – a GByteArray which holds the DER encoded issuer DN.

  • interaction – used to interact with the user if necessary

  • flags – Flags which affect the lookup operation.

  • cancellable – a Cancellable, or None

lookup_certificates_issued_by_async(issuer_raw_dn: Sequence[int], interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

Asynchronously look up certificates issued by this issuer in the database. See lookup_certificates_issued_by() for more information.

The database may choose to hold a reference to the issuer byte array for the duration of this asynchronous operation. The byte array should not be modified during this time.

Added in version 2.30.

Parameters:

  • issuer_raw_dn – a GByteArray which holds the DER encoded issuer DN.

  • interaction – used to interact with the user if necessary

  • flags – Flags which affect the lookup operation.

  • cancellable – a Cancellable, or None

  • callback – callback to call when the operation completes

  • user_data – the data to pass to the callback function

lookup_certificates_issued_by_finish(result: AsyncResult) → list[TlsCertificate]

Finish an asynchronous lookup of certificates. See lookup_certificates_issued_by() for more information.

Added in version 2.30.

Parameters:

result – a AsyncResult.

verify_chain(chain: TlsCertificate, purpose: str, identity: SocketConnectable | None, interaction: TlsInteraction | None, flags: TlsDatabaseVerifyFlags, cancellable: Cancellable | None = None) → TlsCertificateFlags

Determines the validity of a certificate chain, outside the context of a TLS session.

chain is a chain of TlsCertificate objects each pointing to the next certificate in the chain by its TlsCertificate:issuer property.

purpose describes the purpose (or usage) for which the certificate is being used. Typically purpose will be set to TLS_DATABASE_PURPOSE_AUTHENTICATE_SERVER which means that the certificate is being used to authenticate a server (and we are acting as the client).

The identity is used to ensure the server certificate is valid for the expected peer identity. If the identity does not match the certificate, BAD_IDENTITY will be set in the return value. If identity is None, that bit will never be set in the return value. The peer identity may also be used to check for pinned certificates (trust exceptions) in the database. These may override the normal verification process on a host-by-host basis.

Currently there are no flags, and NONE should be used.

If chain is found to be valid, then the return value will be 0. If chain is found to be invalid, then the return value will indicate at least one problem found. If the function is unable to determine whether chain is valid (for example, because cancellable is triggered before it completes) then the return value will be GENERIC_ERROR and error will be set accordingly. error is not set when chain is successfully analyzed but found to be invalid.

GLib guarantees that if certificate verification fails, at least one error will be set in the return value, but it does not guarantee that all possible errors will be set. Accordingly, you may not safely decide to ignore any particular type of error. For example, it would be incorrect to mask EXPIRED if you want to allow expired certificates, because this could potentially be the only error flag set even if other problems exist with the certificate.

Prior to GLib 2.48, GLib’s default TLS backend modified chain to represent the certification path built by TlsDatabase during certificate verification by adjusting the TlsCertificate:issuer property of each certificate in chain. Since GLib 2.48, this no longer occurs, so you cannot rely on TlsCertificate:issuer to represent the actual certification path used during certificate verification.

Because TLS session context is not used, TlsDatabase may not perform as many checks on the certificates as TlsConnection would. For example, certificate constraints may not be honored, and revocation checks may not be performed. The best way to verify TLS certificates used by a TLS connection is to let TlsConnection handle the verification.

The TLS backend may attempt to look up and add missing certificates to the chain. This may involve HTTP requests to download missing certificates.

This function can block. Use verify_chain_async() to perform the verification operation asynchronously.

Added in version 2.30.

Parameters:

  • chain – a TlsCertificate chain

  • purpose – the purpose that this certificate chain will be used for.

  • identity – the expected peer identity

  • interaction – used to interact with the user if necessary

  • flags – additional verify flags

  • cancellable – a Cancellable, or None

verify_chain_async(chain: TlsCertificate, purpose: str, identity: SocketConnectable | None, interaction: TlsInteraction | None, flags: TlsDatabaseVerifyFlags, cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

Asynchronously determines the validity of a certificate chain after looking up and adding any missing certificates to the chain. See verify_chain() for more information.

Added in version 2.30.

Parameters:

  • chain – a TlsCertificate chain

  • purpose – the purpose that this certificate chain will be used for.

  • identity – the expected peer identity

  • interaction – used to interact with the user if necessary

  • flags – additional verify flags

  • cancellable – a Cancellable, or None

  • callback – callback to call when the operation completes

  • user_data – the data to pass to the callback function

verify_chain_finish(result: AsyncResult) → TlsCertificateFlags

Finish an asynchronous verify chain operation. See verify_chain() for more information.

If chain is found to be valid, then the return value will be 0. If chain is found to be invalid, then the return value will indicate the problems found. If the function is unable to determine whether chain is valid or not (eg, because cancellable is triggered before it completes) then the return value will be GENERIC_ERROR and error will be set accordingly. error is not set when chain is successfully analyzed but found to be invalid.

Added in version 2.30.

Parameters:

result – a AsyncResult.

Virtual Methods

class TlsDatabase
do_create_certificate_handle(certificate: TlsCertificate) → str | None

Create a handle string for the certificate. The database will only be able to create a handle for certificates that originate from the database. In cases where the database cannot create a handle for a certificate, None will be returned.

This handle should be stable across various instances of the application, and between applications. If a certificate is modified in the database, then it is not guaranteed that this handle will continue to point to it.

Added in version 2.30.

Parameters:

certificate – certificate for which to create a handle.

do_lookup_certificate_for_handle(handle: str, interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None) → TlsCertificate | None

Look up a certificate by its handle.

The handle should have been created by calling create_certificate_handle() on a TlsDatabase object of the same TLS backend. The handle is designed to remain valid across instantiations of the database.

If the handle is no longer valid, or does not point to a certificate in this database, then None will be returned.

This function can block, use lookup_certificate_for_handle_async() to perform the lookup operation asynchronously.

Added in version 2.30.

Parameters:

  • handle – a certificate handle

  • interaction – used to interact with the user if necessary

  • flags – Flags which affect the lookup.

  • cancellable – a Cancellable, or None

do_lookup_certificate_for_handle_async(handle: str, interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

Asynchronously look up a certificate by its handle in the database. See lookup_certificate_for_handle() for more information.

Added in version 2.30.

Parameters:

  • handle – a certificate handle

  • interaction – used to interact with the user if necessary

  • flags – Flags which affect the lookup.

  • cancellable – a Cancellable, or None

  • callback – callback to call when the operation completes

  • user_data – the data to pass to the callback function

do_lookup_certificate_for_handle_finish(result: AsyncResult) → TlsCertificate

Finish an asynchronous lookup of a certificate by its handle. See lookup_certificate_for_handle() for more information.

If the handle is no longer valid, or does not point to a certificate in this database, then None will be returned.

Added in version 2.30.

Parameters:

result – a AsyncResult.

do_lookup_certificate_issuer(certificate: TlsCertificate, interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None) → TlsCertificate

Look up the issuer of certificate in the database. The TlsCertificate:issuer property of certificate is not modified, and the two certificates are not hooked into a chain.

This function can block. Use lookup_certificate_issuer_async() to perform the lookup operation asynchronously.

Beware this function cannot be used to build certification paths. The issuer certificate returned by this function may not be the same as the certificate that would actually be used to construct a valid certification path during certificate verification. RFC 4158 explains why an issuer certificate cannot be naively assumed to be part of the the certification path (though GLib’s TLS backends may not follow the path building strategies outlined in this RFC). Due to the complexity of certification path building, GLib does not provide any way to know which certification path will actually be used when verifying a TLS certificate. Accordingly, this function cannot be used to make security-related decisions. Only GLib itself should make security decisions about TLS certificates.

Added in version 2.30.

Parameters:

  • certificate – a TlsCertificate

  • interaction – used to interact with the user if necessary

  • flags – flags which affect the lookup operation

  • cancellable – a Cancellable, or None

do_lookup_certificate_issuer_async(certificate: TlsCertificate, interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

Asynchronously look up the issuer of certificate in the database. See lookup_certificate_issuer() for more information.

Added in version 2.30.

Parameters:

  • certificate – a TlsCertificate

  • interaction – used to interact with the user if necessary

  • flags – flags which affect the lookup operation

  • cancellable – a Cancellable, or None

  • callback – callback to call when the operation completes

  • user_data – the data to pass to the callback function

do_lookup_certificate_issuer_finish(result: AsyncResult) → TlsCertificate

Finish an asynchronous lookup issuer operation. See lookup_certificate_issuer() for more information.

Added in version 2.30.

Parameters:

result – a AsyncResult.

do_lookup_certificates_issued_by(issuer_raw_dn: Sequence[int], interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None) → list[TlsCertificate]

Look up certificates issued by this issuer in the database.

This function can block, use lookup_certificates_issued_by_async() to perform the lookup operation asynchronously.

Added in version 2.30.

Parameters:

  • issuer_raw_dn – a GByteArray which holds the DER encoded issuer DN.

  • interaction – used to interact with the user if necessary

  • flags – Flags which affect the lookup operation.

  • cancellable – a Cancellable, or None

do_lookup_certificates_issued_by_async(issuer_raw_dn: Sequence[int], interaction: TlsInteraction | None, flags: TlsDatabaseLookupFlags, cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

Asynchronously look up certificates issued by this issuer in the database. See lookup_certificates_issued_by() for more information.

The database may choose to hold a reference to the issuer byte array for the duration of this asynchronous operation. The byte array should not be modified during this time.

Added in version 2.30.

Parameters:

  • issuer_raw_dn – a GByteArray which holds the DER encoded issuer DN.

  • interaction – used to interact with the user if necessary

  • flags – Flags which affect the lookup operation.

  • cancellable – a Cancellable, or None

  • callback – callback to call when the operation completes

  • user_data – the data to pass to the callback function

do_lookup_certificates_issued_by_finish(result: AsyncResult) → list[TlsCertificate]

Finish an asynchronous lookup of certificates. See lookup_certificates_issued_by() for more information.

Added in version 2.30.

Parameters:

result – a AsyncResult.

do_verify_chain(chain: TlsCertificate, purpose: str, identity: SocketConnectable | None, interaction: TlsInteraction | None, flags: TlsDatabaseVerifyFlags, cancellable: Cancellable | None = None) → TlsCertificateFlags

Determines the validity of a certificate chain, outside the context of a TLS session.

chain is a chain of TlsCertificate objects each pointing to the next certificate in the chain by its TlsCertificate:issuer property.

purpose describes the purpose (or usage) for which the certificate is being used. Typically purpose will be set to TLS_DATABASE_PURPOSE_AUTHENTICATE_SERVER which means that the certificate is being used to authenticate a server (and we are acting as the client).

The identity is used to ensure the server certificate is valid for the expected peer identity. If the identity does not match the certificate, BAD_IDENTITY will be set in the return value. If identity is None, that bit will never be set in the return value. The peer identity may also be used to check for pinned certificates (trust exceptions) in the database. These may override the normal verification process on a host-by-host basis.

Currently there are no flags, and NONE should be used.

If chain is found to be valid, then the return value will be 0. If chain is found to be invalid, then the return value will indicate at least one problem found. If the function is unable to determine whether chain is valid (for example, because cancellable is triggered before it completes) then the return value will be GENERIC_ERROR and error will be set accordingly. error is not set when chain is successfully analyzed but found to be invalid.

GLib guarantees that if certificate verification fails, at least one error will be set in the return value, but it does not guarantee that all possible errors will be set. Accordingly, you may not safely decide to ignore any particular type of error. For example, it would be incorrect to mask EXPIRED if you want to allow expired certificates, because this could potentially be the only error flag set even if other problems exist with the certificate.

Prior to GLib 2.48, GLib’s default TLS backend modified chain to represent the certification path built by TlsDatabase during certificate verification by adjusting the TlsCertificate:issuer property of each certificate in chain. Since GLib 2.48, this no longer occurs, so you cannot rely on TlsCertificate:issuer to represent the actual certification path used during certificate verification.

Because TLS session context is not used, TlsDatabase may not perform as many checks on the certificates as TlsConnection would. For example, certificate constraints may not be honored, and revocation checks may not be performed. The best way to verify TLS certificates used by a TLS connection is to let TlsConnection handle the verification.

The TLS backend may attempt to look up and add missing certificates to the chain. This may involve HTTP requests to download missing certificates.

This function can block. Use verify_chain_async() to perform the verification operation asynchronously.

Added in version 2.30.

Parameters:

  • chain – a TlsCertificate chain

  • purpose – the purpose that this certificate chain will be used for.

  • identity – the expected peer identity

  • interaction – used to interact with the user if necessary

  • flags – additional verify flags

  • cancellable – a Cancellable, or None

do_verify_chain_async(chain: TlsCertificate, purpose: str, identity: SocketConnectable | None, interaction: TlsInteraction | None, flags: TlsDatabaseVerifyFlags, cancellable: Cancellable | None = None, callback: Callable[[...], None] | None = None, *user_data: Any) → None

Asynchronously determines the validity of a certificate chain after looking up and adding any missing certificates to the chain. See verify_chain() for more information.

Added in version 2.30.

Parameters:

  • chain – a TlsCertificate chain

  • purpose – the purpose that this certificate chain will be used for.

  • identity – the expected peer identity

  • interaction – used to interact with the user if necessary

  • flags – additional verify flags

  • cancellable – a Cancellable, or None

  • callback – callback to call when the operation completes

  • user_data – the data to pass to the callback function

do_verify_chain_finish(result: AsyncResult) → TlsCertificateFlags

Finish an asynchronous verify chain operation. See verify_chain() for more information.

If chain is found to be valid, then the return value will be 0. If chain is found to be invalid, then the return value will indicate the problems found. If the function is unable to determine whether chain is valid or not (eg, because cancellable is triggered before it completes) then the return value will be GENERIC_ERROR and error will be set accordingly. error is not set when chain is successfully analyzed but found to be invalid.

Added in version 2.30.

Parameters:

result – a AsyncResult.

Fields

class TlsDatabase
parent_instance
priv