I have created self-signed SSL certificate using OpenSSL as follow:
openssl req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 365
This gave me certificate and private key in .pem file. I need to provide my public key to my clients in .cer or .crt format. Is there any way to get public key in .cer/.crt formats?
What I have already tried:
1. Generating public key in .pem format and trying to convert it to .cer or .crt [Didn't work]
To extract public key in .pem file [worked fine]:
`openssl x509 -pubkey -noout -in signer-cert.pem > signer-public-key-test.pem`
To convert it from .pem for .cer format
openssl x509 -inform PEM -in signer-public-key-test.pem -outform DER -out signer-public-key-test.cer
I get this error:
unable to load certificate
140067363030680:error:0906D06C:PEM routines:PEM_read_bio:no start line:pem_lib.c:701:Expecting: TRUSTED CERTIFICATE
2. Converting my certificate to .cer (which I did fine) and trying to export public key using windows certificate export wizard as instructions given here
It didn't work either. I couldn't enable the option to export keys and the final output, when opened in notepad++ was garbage.
So my question is, is there any way to generate the certificate from scratch and have the public key in .cer or .crt file. OR generating the certificate in .pem format and later extracting public keys to .crt or .cer
Any help is deeply appreciated.
Since .cer and .crt usually mean "DER or PEM-DER X.509 certificate" I don't know what you mean by having the public key in that format.
If you mean you want a DER encoded SubjectPublicKeyInfo representing the public key, the second stage of your pipeline would be
openssl asn1parse -noout -out some.file
You can remove the intermediate with
openssl x509 -in signer-cert.pem -noout -pubkey |
openssl asn1parse -noout -out signer-public-key-test.der
(Newline added to remove scrollbar)
Or, skip the certificate middleman altogether:
openssl rsa -in key.pem -pubout -outform der -out signer-public-key-test.der
Seems pretty weird that you want that particular format, though.
Related
I have create .pem file from .cert file using the below line in openssl.exe :
OpenSSL> x509 -inform der -in C:\Certificate\Binary_Certificate_245568.cer -out C:\Certificate\Binary_Cert.pem
It worked without any issues.
Then when I try to generate the pfx file from .cert and .pem file using the following statement I get error:
OpenSSL> pkcs12 -inkey C:\Certificate\Binary_Cert.pem -in C:\Certificate\Binary_Certificate_245568.cer -export -out C:\Certificate\SGS_VS_CERT.pfx
unable to load private key
34359836736:error:08064066:object identifier routines:OBJ_create:oid exists:crypto/objects/obj_dat.c:698:
34359836736:error:0909006C:PEM routines:get_name:no start line:crypto/pem/pem_lib.c:745:
error in pkcs12
Can anyone please advise what I am doing wrong as I need to generate .pfx file. Thanks
You can follow steps given below in order to create .pfx certificate by combining the external CA issued server(.cer), intermediate(.cer) and root(.cer) certificates into one file (.pfx) on redhat linux server using openssl tool :
A) To run below command for generating the CSR in linux using openssl tool -
[user#machine]$ openssl req -new -nodes -newkeys rsa:2048 -keyout myapp.mydomain.com.key -out myapp.mydomain.com.csr -sha256
Note : -nodes means 'NOT TO USE DES ALOGORITHM' and create multiple backup of this key file, which will be used again during certificate renewal.
B) To generate .pfx ( certificate chain sequence to be SERVER-CER --> INTERMEDIATE-CERT --> ROOT-CERT ) in linux using openssl.
SERVER-CERT myapp.mydomain.com.cer
INTERMEDIATE-CERT myintermediatecert.com.cer
ROOT-CERT myrootcert.cer
KEY FILE myapp.mydomain.com.key
STEP 1 - To combine all certificates in one pem certificate(myapp.mydomain.pem) using command 'cat' in redhat.
[user#machine]$ cat myapp.mydomain.com.cer myintermediatecert.com.cer myrootcert.cer > myapp.mydomain.com.pem (output pem cert)
STEP 2 - To convert PEM to PFX by importing the private key with password configured.
[user#machine]$ openssl pkcs12 -export -out myapp.mydomain.com.pfx -inkey myapp.mydomain.com.key -in myapp.mydomain.com.pem
Note : you will get an option to set the password to output .pfx file.
STEP 3 : To verify .pfx file using openssl by entering the password.
[user#machine]$ openssl pkcs12 -in myapp.mydomain.com.pfx -info
I'm having some weird issues with generating CSRs and certificates from them which I don't fully understand.
Here's what I've done:
Generate private key and CSR (done on Ubuntu on WSL if that's of any significance)
openssl req -newkey rsa:2048 -keyout PRIVATEKEY.key -out MYCSR.csr
Uploaded that to CA and got back a certificate beginning with -----BEGIN CERTIFICATE----- which would indicate a PEM-encoded certificate, right?
Tried combining all of this into a PFX for ease of use
openssl pkcs12 -export -out CERTIFICATE.pfx -inkey PRIVATEKEY.key -in CERTIFICATE.cer
It then asks for the private key and then throws the error No certificate matches private key
Some people suggested reencoding the certificate from DER to PEM, but that just throws an error indicating the certificate is already X509
sudo openssl x509 -inform DER -outform PEM -in CERTIFICATE.cer -out CERTIFICATE.pem
unable to load certificate
140390322082240:error:0D0680A8:asn1 encoding routines:asn1_check_tlen:wrong tag:../crypto/asn1/tasn_dec.c:1130:
140390322082240:error:0D07803A:asn1 encoding routines:asn1_item_embed_d2i:nested asn1 error:../crypto/asn1/tasn_dec.c:290:Type=X509
The following command generates quite sensible output, so the certificate seems to be alright to some extent
openssl x509 -in CERTIFICATE.cer -text -noout
The CA is Telia if this is of any use to anybody. I have had some issues in the past with them, for example Digicert's Certificate Utility doesn't recognize their certificates as valid for some reason (but that might of course be cause by me using the wrong file extension or something).
This issue was due to the renewal process in the Telia user interface, it allows you to upload a new CSR during renewal, but it actually ignores that and uses the old CSR without telling you.
I used openSSL to create a .key and .csr file.
openssl req -new -newkey rsa:2048 -passout pass:myPassword -nodes -out myDomainName.csr -keyout myDomainName.key
I know the .csr file needs to be submitted to the certificate authority, but my asp net core object is expecting a .pfx file as input (I think)... how do I get the .pfx file ?? Do I convert the .key to .pfx somehow?
options.Listen(ipAddress, 443, listenOptions => {
listenOptions.UseHttps("myCertificate.pfx" /* how to get this file? */, password);
});
A csr (Certificate Signing Request) file is used by a Certificate Authority to create an SSL for you, which is the one that you use in your app, there is no conversion from csr to pfx you can do locally.
Note: They do not need your private key for this.
For a free alternative you can use this CA
Yes you can convert certificate csr + key files to pfx on your local machine by using openssl (understanding csr as certificate request and key as certificate private key).
To do so, you need to go into bin directory in openssl (at my machine it is located in c:\Program Files\OpenSSL-Win64\bin), copy there your csr + key files and run these two commands:
First you need to make a crt from csr + key
openssl x509 -req -in certificate.csr -signkey key.pem -out certificate.crt
Next you make pfx from crt + key
openssl pkcs12 -export -in certificate.crt -inkey key.pem -out certificate.pfx
Where key.pem is a file with your private key, and certificate.csr is a file with csr.
Done!
Of course you may want to use different options than defaults for your target key, so in that case please read more about openssl.
I'm trying to sign a PDF in a PHP script with a certificate. Until now, I executed my test with a self-signed .crt file, generated with the command line :
openssl req -x509 -nodes -days 365000 -newkey rsa:1024 \
-keyout tcpdf.crt -out tcpdf.crt
(yes, i'm using tcpdf). It works fine.
But know, my company gave me real certificates (from tbs-certificats), and I'm a bit disappointed: I've a .cer, a .pem and a .p7b file...
I tried to use each of them in my script, but I've the error
Warning: openssl_pkcs7_sign(): error getting private key
The code I use with a self-signed certificate :
// set certificate file
$certificate = 'file://data/cert/tcpdf.crt';
// set document signature
$pdf->setSignature($certificate, $certificate);
May I change something ? I'm not very familiar with the crypto world...
We'll, first things first, you have to point your script to an existing file. In this case, the .cer file would contain the certificate, so try that instead of "/path/file.CRT".
Now the file extension vs. how the certificate is encoded is kinda unrelated I'm afraid, even if the names are inducing some confusion, see this reference.
I have no idea whether tcpdf supports both pem and der encoded files, because of the lack of documentation. They probably do, but just in case, here's how to work around it. Test commands will give you an "unable to load certificate" error if you assume the wrong encoding.
testing for pem encoded files : openssl x509 -in cert.cer -text -noout
testing for der encoded files : openssl x509 -in certificate.der -inform der -text -noout
conversion from PEM to DER openssl x509 -in cert.cer -outform der -out cert.der
conversion from DER to PEM openssl x509 -in cert.cer -inform der -outform pem -out cert.pem
Can anyone tell me the correct way/command to extract/convert the certificate .crt and private key .key files from a .pem file? I just read they are interchangable, but not how.
I was able to convert pem to crt using this:
openssl x509 -outform der -in your-cert.pem -out your-cert.crt
Converting Using OpenSSL
These commands allow you to convert certificates and keys to different formats to make them compatible with specific types of servers or software.
Convert a DER file (.crt .cer .der) to PEM
openssl x509 -inform der -in certificate.cer -out certificate.pem
Convert a PEM file to DER
openssl x509 -outform der -in certificate.pem -out certificate.der
Convert a PKCS#12 file (.pfx .p12) containing a private key and certificates to PEM
openssl pkcs12 -in keyStore.pfx -out keyStore.pem -nodes
You can add -nocerts to only output the private key or add -nokeys to only output the certificates.
Convert a PEM certificate file and a private key to PKCS#12 (.pfx .p12)
openssl pkcs12 -export -out certificate.pfx -inkey privateKey.key -in certificate.crt -certfile CACert.crt
Convert PEM to CRT (.CRT file)
openssl x509 -outform der -in certificate.pem -out certificate.crt
OpenSSL Convert PEM
Convert PEM to DER
openssl x509 -outform der -in certificate.pem -out certificate.der
Convert PEM to P7B
openssl crl2pkcs7 -nocrl -certfile certificate.cer -out certificate.p7b -certfile CACert.cer
Convert PEM to PFX
openssl pkcs12 -export -out certificate.pfx -inkey privateKey.key -in certificate.crt -certfile CACert.crt
OpenSSL Convert DER
Convert DER to PEM
openssl x509 -inform der -in certificate.cer -out certificate.pem
OpenSSL Convert P7B
Convert P7B to PEM
openssl pkcs7 -print_certs -in certificate.p7b -out certificate.cer
Convert P7B to PFX
openssl pkcs7 -print_certs -in certificate.p7b -out certificate.cer
openssl pkcs12 -export -in certificate.cer -inkey privateKey.key -out certificate.pfx -certfile CACert.cer
OpenSSL Convert PFX
Convert PFX to PEM
openssl pkcs12 -in certificate.pfx -out certificate.cer -nodes
Generate rsa keys by OpenSSL
Using OpenSSL on the command line you’d first need to generate a public and private key, you should password protect this file using the -passout argument, there are many different forms that this argument can take so consult the OpenSSL documentation about that.
openssl genrsa -out private.pem 1024
This creates a key file called private.pem that uses 1024 bits. This file actually have both the private and public keys, so you should extract the public one from this file:
openssl rsa -in private.pem -out public.pem -outform PEM -pubout
or
openssl rsa -in private.pem -pubout > public.pem
or
openssl rsa -in private.pem -pubout -out public.pem
You’ll now have public.pem containing just your public key, you can freely share this with 3rd parties.
You can test it all by just encrypting something yourself using your public key and then decrypting using your private key, first we need a bit of data to encrypt:
Example file :
echo 'too many secrets' > file.txt
You now have some data in file.txt, lets encrypt it using OpenSSL and
the public key:
openssl rsautl -encrypt -inkey public.pem -pubin -in file.txt -out file.ssl
This creates an encrypted version of file.txt calling it file.ssl, if
you look at this file it’s just binary junk, nothing very useful to
anyone. Now you can unencrypt it using the private key:
openssl rsautl -decrypt -inkey private.pem -in file.ssl -out decrypted.txt
You will now have an unencrypted file in decrypted.txt:
cat decrypted.txt
|output -> too many secrets
RSA TOOLS Options in OpenSSL
NAME
rsa - RSA key processing tool
SYNOPSIS
openssl rsa [-help] [-inform PEM|NET|DER] [-outform PEM|NET|DER] [-in filename] [-passin arg] [-out filename] [-passout arg] [-aes128] [-aes192] [-aes256] [-camellia128] [-camellia192] [-camellia256] [-des] [-des3] [-idea] [-text] [-noout] [-modulus] [-check] [-pubin] [-pubout] [-RSAPublicKey_in] [-RSAPublicKey_out] [-engine id]
DESCRIPTION
The rsa command processes RSA keys. They can be converted between various forms and their components printed out. Note this command uses the traditional SSLeay compatible format for private key encryption: newer applications should use the more secure PKCS#8 format using the pkcs8 utility.
COMMAND OPTIONS
-help
Print out a usage message.
-inform DER|NET|PEM
This specifies the input format. The DER option uses an ASN1 DER encoded form compatible with the PKCS#1 RSAPrivateKey or SubjectPublicKeyInfo format. The PEM form is the default format: it consists of the DER format base64 encoded with additional header and footer lines. On input PKCS#8 format private keys are also accepted. The NET form is a format is described in the NOTES section.
-outform DER|NET|PEM
This specifies the output format, the options have the same meaning as the -inform option.
-in filename
This specifies the input filename to read a key from or standard input if this option is not specified. If the key is encrypted a pass phrase will be prompted for.
-passin arg
the input file password source. For more information about the format of arg see the PASS PHRASE ARGUMENTS section in openssl.
-out filename
This specifies the output filename to write a key to or standard output if this option is not specified. If any encryption options are set then a pass phrase will be prompted for. The output filename should not be the same as the input filename.
-passout password
the output file password source. For more information about the format of arg see the PASS PHRASE ARGUMENTS section in openssl.
-aes128|-aes192|-aes256|-camellia128|-camellia192|-camellia256|-des|-des3|-idea
These options encrypt the private key with the specified cipher before outputting it. A pass phrase is prompted for. If none of these options is specified the key is written in plain text. This means that using the rsa utility to read in an encrypted key with no encryption option can be used to remove the pass phrase from a key, or by setting the encryption options it can be use to add or change the pass phrase. These options can only be used with PEM format output files.
-text
prints out the various public or private key components in plain text in addition to the encoded version.
-noout
this option prevents output of the encoded version of the key.
-modulus
this option prints out the value of the modulus of the key.
-check
this option checks the consistency of an RSA private key.
-pubin
by default a private key is read from the input file: with this option a public key is read instead.
-pubout
by default a private key is output: with this option a public key will be output instead. This option is automatically set if the input is a public key.
-RSAPublicKey_in, -RSAPublicKey_out
like -pubin and -pubout except RSAPublicKey format is used instead.
-engine id
specifying an engine (by its unique id string) will cause rsa to attempt to obtain a functional reference to the specified engine, thus initialising it if needed. The engine will then be set as the default for all available algorithms.
NOTES
The PEM private key format uses the header and footer lines:
-----BEGIN RSA PRIVATE KEY-----
-----END RSA PRIVATE KEY-----
The PEM public key format uses the header and footer lines:
-----BEGIN PUBLIC KEY-----
-----END PUBLIC KEY-----
The PEM RSAPublicKey format uses the header and footer lines:
-----BEGIN RSA PUBLIC KEY-----
-----END RSA PUBLIC KEY-----
The NET form is a format compatible with older Netscape servers and Microsoft IIS .key files, this uses unsalted RC4 for its encryption. It is not very secure and so should only be used when necessary.
Some newer version of IIS have additional data in the exported .key files. To use these with the utility, view the file with a binary editor and look for the string "private-key", then trace back to the byte sequence 0x30, 0x82 (this is an ASN1 SEQUENCE). Copy all the data from this point onwards to another file and use that as the input to the rsa utility with the -inform NET option.
EXAMPLES
To remove the pass phrase on an RSA private key:
openssl rsa -in key.pem -out keyout.pem
To encrypt a private key using triple DES:
openssl rsa -in key.pem -des3 -out keyout.pem
To convert a private key from PEM to DER format:
openssl rsa -in key.pem -outform DER -out keyout.der
To print out the components of a private key to standard output:
openssl rsa -in key.pem -text -noout
To just output the public part of a private key:
openssl rsa -in key.pem -pubout -out pubkey.pem
Output the public part of a private key in RSAPublicKey format:
openssl rsa -in key.pem -RSAPublicKey_out -out pubkey.pem
To extract the key and cert from a pem file:
Extract key
openssl pkey -in foo.pem -out foo.key
Another method of extracting the key...
openssl rsa -in foo.pem -out foo.key
Extract all the certs, including the CA Chain
openssl crl2pkcs7 -nocrl -certfile foo.pem | openssl pkcs7 -print_certs -out foo.cert
Extract the textually first cert as DER
openssl x509 -in foo.pem -outform DER -out first-cert.der
Pre-requisite
openssl should be installed.
On Windows, if Git Bash is installed, try that! Alternate binaries can be found here.
Step 1: Extract .key from .pem
openssl pkey -in cert.pem -out cert.key
Step 2: Extract .crt from .pem
openssl crl2pkcs7 -nocrl -certfile cert.pem | openssl pkcs7 -print_certs -out cert.crt
This is what I did on windows.
Download a zip file that contains the open ssl exe from Google
Unpack the zip file and go into the bin folder.
Go to the address bar in the bin folder and type cmd. This will open a command prompt at this folder.
move/Put the .pem file into this bin folder.
Run two commands. One creates the cert and the second the key file
openssl x509 -outform der -in yourPemFilename.pem -out certfileOutName.crt
openssl rsa -in yourPemFilename.pem -out keyfileOutName.key
If you asked this question because you're using mkcert then the trick is that the .pem file is the cert and the -key.pem file is the key.
(You don't need to convert, just run mkcert yourdomain.dev otherdomain.dev )
A .crt stores the certificate.. in pem format. So a .pem, while it can also have other things like a csr (Certificate signing request), a private key, a public key, or other certs, when it is storing just a cert, is the same thing as a .crt.
A pem is a base 64 encoded file with a header and a footer between each section.
To extract a particular section, a perl script such as the following is totally valid, but feel free to use some of the openssl commands.
perl -ne "\$n++ if /BEGIN/; print if \$n == 1 && /BEGIN/.../END/;" mydomain.pem
where ==1 can be changed to which ever section you need. Obviously if you know exactly the header and footer you require and there is only one of those in the file (usually the case if you keep just the cert and the key in there), you can simplify it:
perl -ne "print if /^-----BEGIN CERTIFICATE-----\$/.../END/;" mydomain.pem