In fact, the term X.509 certificate usually refers to the PKIX certificate of IETF and the CRL file of X.509 v3 certificate standard, which is stipulated in RFC 5280 (commonly known as PKIX of public key infrastructure (X.509)).
The first thing we need to know is the file extension of each type. Many people don't know what the endings of DER, PEM, CRT and CER are, and what's more, they are wrongly interchangeable. In some cases, some are interchangeable, and the best practice is to identify the encoding method of the certificate and then mark it correctly. Certificates with the correct labels will be easier to operate.
Yes. The DER extension is used for binary DER encoding certificates.
These files may also contain CER or CRT extensions. The correct statement is "I have a DER-encoded certificate", not "I have a DER certificate".
Yes. PEM extension is used for different types of X.509v3 files, which are ASCII(Base64) data prefixed with "-BEGIN ...".
Yes. CRT extensions are used for certificates. Certificates can be encoded as binary DER or ASCII PEM. CER and CRT extensions are almost synonyms. It is most common in Unix or Unix-like systems.
Cer is. Microsoft convention. You can convert. Crt entry. CER(。 By the encoded cer. Bode is still. Cer encoded by base64 [PEM]).
Yes. The cer file extension is also recognized by IE as a command to run the MS cryptoAPI command (especially in cryptext.dll and rundll32.exe), which displays a dialog box for importing and/or viewing certificate contents.
Yes. Key extension is used for public key and private key PKCS # 8. The key can be encoded as binary DER or ASCII PEM.
There are four basic types of certificate operations. View, transform, combine and extract.
Even if PEM-encoded certificates are ASCII, they are unreadable. Here are some commands that allow you to output the contents of the certificate in a readable form;
If you encounter this error, it means that you are trying to view a DER-encoded certificate, and you need to use the command in "View a DER-encoded certificate".
Unable to load certificate 12626: Error: 0906d06c: pemroutines: pem _ read _ bio: No starting line: pem_lib.c:647: TRUSTEDCERTIFICATE expected.
If you encounter the following error, it means that you are trying to view a PEM-encoded certificate using the DER encoded certificate command. Use the commands in View PEM-encoded certificates.
Unable to load the certificate 13978: error: 0D0680A8:asn 1 encoding routine: ASN 1_CHECK_TLEN: wrong token: tasn _ dec.c:1306:1396.
Transformation can store one type of encoding certificate in another type. (i.e. PEM to DER conversion)
PEM to DER
DER to PEM
In some cases, it is beneficial to merge multiple X.509 infrastructures into a single file. A common example is to merge the private key and the public key into the same certificate.
The easiest way to combine keys and chains is to convert each file into a PEM-encoded certificate, and then simply copy the contents of each file into a new file. This applies to applications that combine files in Apache.
Some certificates will appear in combination. A file can contain any of the following: certificate, private key, public key, signing certificate, certificate authority (CA) and/or chain of authorities.