Overview[1]#
Certificate is a credential issued by an Identity Provider (IDP) (Certificate Authority) and is used by a Relying Party that trusts the Identity Provider (IDP) (Certificate Authority) by way of the Trust AnchorCertificate is an binary data structure containing element of Public Key cryptography that may be used to perform Asymmetric Key Cryptography.
In particular, a Certificate consists of a pair of keys (called the "Public Key" and the "Private Key") that are linked so that any data encrypted using the Public Key can ONLY be decrypted using the Private Key. With many Public Key algorithms, like RSA, the reverse is also true so that any data encrypted with the Private Key can ONLY be decrypted using the Public Key.
Certificate bind together:
- A domain name, server name or hostname.
- A Digital Identity of an Organizational Entity (i.e. company name) and location.
Certificate are the electronic counterparts to driver licenses, passport, Payment Cards and loyalty Cards.
Certificate can be used to establish Encryption, Identification, Authentication and Confidentiality and with a little bit of additional effort even Authorization.
Certificates provide an Assertion by the Certificate Authority (or Registration Authority) of Identification by binding an Digital Identity to a Private Key and Public Key which, is by definition, Authentication.
Different Meanings#
The term "Certificate" may have different meanings based on the context in which it is used. In many cases, Certificate refers to only the Public Key (in particular, whenever the server presents its Certificate to the client, or if a client presents only the Public Key certificate to the server, then only the Public Key is included). However, in other cases, it does include the Private Key (i.e., the server will require the use of the Private Key to establish a secure communication channel with the client, and the client will need access to its Private Key in order to send its own certificate to the server).Most often, Certificate is in reference to a X.509 Certificate.
We use the following specific terms:
- Site Certificate - for any Certificate presented by a server.
- Subject Certificate for any Certificate that is NOT a Trusted Certificate (though it may be in the future)
- Trusted Certificate for any Certificate that is Trusted
- Intermediate Certificate for any Certificate Signed by a Root Certificate that issues Certificates
- Root Certificate for any Root Certificate (Trust Anchor) and is implied to be a Trusted Certificate
- Identity Certificate - any Certificate with a Public Key
- Certificate - when used alone might be any of the above and should be taken in context
LDAP and Certificate#
The LDAPSyntaxes for Certificate is 1.3.6.1.4.1.1466.115.121.1.8.Certificates have two primary uses with LDAP servers. First, and most common, is for providing a secure communication mechanism, generally through the use of SSL or StartTLS. In this case, the negotiation process involves the client encrypting information using the server's Public Key so that only the server can decrypt it using its Public Key and that information will be Confidential.
Structure of a Certificate[2]#
The structure foreseen by the standards is expressed in a formal language, namely Abstract Syntax Notation One. Structure of a X.509 Certificate is shown with the Example CertificateOther Certificate Information#
- Certificate Extensions
- Certificate Fingerprint
- Key pair - Public Key, Private Keys
- Certificate Validation
- Certificate Level Of Assurance
Certificate Security Considerations#
Certificates are typically part of the Public Key Infrastructure and therefore subject to all the Public Key Infrastructure WeaknessesCertificate Formats#
Common filename extensions and Certificate Formats for X.509 certificates are:- .pem – (Privacy Enhanced Mail) Base64 encoded DER certificate, enclosed between "-----BEGIN CERTIFICATE-----" and "-----END CERTIFICATE-----"
- .cer, .crt, .der – usually in binary DER form, but Base64-encoded certificates are common too (see .pem above)
- .p7b, .p7c – PKCS#7 Signed Data structure without data, just certificate(s) or CRL(s)
- .p12 – PKCS#12, may contain certificate(s) (public) and Private Keys (password protected)
- .pfx – PFX, predecessor of PKCS#12 - usually contains data in PKCS#12 format, e.g., with PFX files typically generated in IIS
Single Binary Certificate#
A Single Binary Certificate is a binary data structure containing the fields listed in X.509 certificates. Certificates are encoded using Distinguished Encoding Rules (DER).Be careful when transferring Binary Certificates, remember to transfer a binary certificate in binary format, for example using binary FTP, when you copy to or from a system.
Usually, Binary Certificates are stored in a Certificate File Formats when exported from Certificate Formats and when used to transmit and store certificates.
More Information#
There might be more information for this subject on one of the following:- 1.3.6.1.4.1.1466.115.121.1.8
- 2.16.840.1.113730
- A Low Infrastructure Public Key Mechanism Using SPKM
- API Service Delivery
- Access Control Engine
- AuthorityKeyIdentifier
- Automatic Certificate Management Environment
- Base64
- BasicConstraints
- Best Practices For LDAP Naming Attributes
- Best Practices for LDAP Security
- Biometric Data Challenges
- Blinding Identity Taxonomy
- Blockcerts
- Blockchain 2.0
- Boulder
- Browsers and Certificates
- CA Constraint
- Certbot
- Certificate
- Certificate Algorithm ID
- Certificate Alias
- Certificate Authority
- Certificate Chain
- Certificate Extensions
- Certificate Fingerprint
- Certificate Formats
- Certificate Issuer
- Certificate Keystores
- Certificate Level Of Assurance
- Certificate Management Protocol
- Certificate Pinning
- Certificate Renewal
- Certificate Request Message Format
- Certificate Request Process
- Certificate Revocation
- Certificate Revocation List
- Certificate Serial Number
- Certificate Signature
- Certificate Signature Algorithm
- Certificate Signing Request
- Certificate Subject
- Certificate Transparency
- Certificate Validation
- Certificate Validation Tools
- Certificate Validity Period
- Certificate Version
- Certificate-based Authentication
- CertificateRequest
- CertificateVerify
- Certificate_list
- Certification Authority Browser Forum
- Channel Bindings for TLS
- Client Send Certificate
- ClientKeyExchange
- Compromised Certificate
- Connection-Oriented Media Transport over the Transport Layer Security (TLS) Protocol in the Session Description Protocol (SDP)
- ContentCommitment
- Converting Certificate Formats
- Creating KMO Signed By An External Certificate Authority
- Credential
- Credential Management
- Cross-site request forgery
- Crypt32.dll
- CryptoAPI
- Cryptographic Message Syntax
- DIGEST-MD5
- DNS Certification Authority Authorization
- DNS-Based Authentication of Named Entities
- Data Provenance
- DataEncipherment
- Differences between LDAP 2 and 3 Protocols
- DigiD
- Digital certificate request
- DigitalSignature
- DirXML Engine JVM
- Direct Anonymous Attestation
- Distinguished Encoding Rules
- Distinguished Names
- Dogtag
- Domain Authorization Document
- Domain Validated Certificate
- EMV Terms
- Electronic IDentification Authentication and trust Services
- Encrypted Server Name Indication
- EncryptedExtensions
- Example Certificate
- Extended Validation Certificate
- Glossary Of LDAP And Directory Terminology
- Health Information Services Provider
- How SSL-TLS Works
- How To Crack SSL-TLS
- IAM Charter
- IDM Related Compliance Items
- IMessage
- Identify and Authenticate access to system components
- Identity Certificate
- Importing Certificates In Imanager
- Intermediate Certificate
- Internet Key Exchange
- Internet X.509 Public Key Infrastructure Certificate Policy and Certification Practices Framework
- Issuer
- Issuer Unique Identifier
- JWK Set
- Java KeyStore
- Kerberos SSP
- KeyCertSign
- KeyEncipherment
- KeyUsage
- Keytool
- LDAPs and AD
- LdapKeyMaterialName
- Lets encrypt
- Macaroons
- Mutual Authentication
- Mutual TLS
- Mutual TLS Profiles for OAuth Clients
- Mutual TLS Sender Constrained Resources Access
- NICI
- NIST.SP.800-63B
- NMAS
- NameConstraints
- Ndsconfig Parameters
- Netlogon service
- Netscape Certificate Sequence
- Network Security Services
- Non-Repudiation
- NonRepudiation
- Not After
- Not Before
- OAuth 2.0 Mutual TLS Client Authentication and Certificate Bound Access Tokens
- OAuth Dynamic Client Registration Metadata
- OCSP Stapling
- Obtain a Certificate from Server
- Online Certificate Status Protocol
- Open-Loop Authentication
- OpenSSL
- OpenSSL Commands
- Opportunistic encryption
- PKCS 11
- PKCS 6
- PKCS 8
- PKCS 9
- PKCS12
- PKCS7
- Password
- PathLenConstraint
- Perl LDAPS and Certificates
- Perspectives Project
- Pre-Shared Key Ciphersuites for Transport Layer Security (TLS)
- Privacy-Enhanced Mail
- Privilege Management Infrastructure
- Public Key Cryptography Based User-to-User
- Public Key Infrastructure
- Public Key Infrastructure Weaknesses
- Public-Key Cryptography Standards
- RFC 2459
- RFC 3279
- RFC 3280
- RFC 4055
- RFC 4491
- RFC 4523
- RFC 5280
- RFC 5759
- RFC 6125
- RFC 6818
- RSA Cryptography
- RSA key-exchange
- Registration
- Registration Authority
- Resource Access Control Facility
- Retrieving Edirectory Certificate OpenSSL Toolkit
- Roots of Trust
- SAML Holder of Key
- SASDFM
- SASService
- SDA
- SHA-1
- SHA-1 Deprecation
- SSL Handshake Failed
- SSL-TLS Interception
- SSLAndOurPrograms
- Schannel SSP
- Secure MIME
- Secure Socket Layer
- Self-signed Certificate
- Server Name Indication
- ServerCertificate
- ServerKeyExchange
- Session Management
- Set Active Directory Password From Java
- SignatureAlgorithm
- SignatureValue
- Signing key
- Site Certificate
- Standard Disclaimer
- Subject Alternative Name
- Subject Certificate
- Subject Unique Identifier
- SubjectAltName
- SubjectKeyIdentifier
- TLS 1.3
- TLS Client Authentication
- TLS Session Resumption
- TLS User Mapping Extension
- TLSA
- Token Binding Protocol
- Tomcat And SSL
- Transport Layer Security
- Trust Anchor
- Trusted Certificate
- U-Prove
- Using the Secure Remote Password (SRP) Protocol for TLS Authentication
- Verifying Certificate Signatures
- Web Blog_blogentry_170120_1
- Wildcard Certificates
- X.500
- X.509
- X.509 Style Guide
- X.509v3
- [#1] - SSL Certificate framework 101: How does the browser actually verify the validity of a given server certificate?
- based on 2015-03-16
- [#2] - The First Few Milliseconds of an HTTPS Connection
- based on 2015-03-16