Digital signature for a file using openssl - cryptography

Is there a way to digitally sign a x509 certificate or any document using openssl?

To Generate Private Key
openssl genrsa -out privatekey.pem 2048
To Sign
openssl dgst -sha256 -sign privatekey.pem -out data.txt.signature data.txt
To Generate The Public Key
dgst -verify requires the public key
openssl rsa -in privatekey.pem -outform PEM -pubout -out publickey.pem
To Verify
openssl dgst -sha256 -verify publickey.pem -signature data.txt.signature data.txt
In case of success: prints "Verified OK", return code 0
In case of failure: prints "Verification Failure", return code 1

Yes, the dgst and rsautl component of OpenSSL can be used to compute a signature given an RSA key pair.
Signing:
openssl dgst -sha256 data.txt > hash
openssl rsautl -sign -inkey privatekey.pem -keyform PEM -in hash >signature
Verifying just the signature:
openssl rsautl -verify -inkey publickey.pem -pubin -keyform PEM -in signature
Update: Capturing Reto's comments from below because this is an important nuance. Presumably if you are going to the trouble to verify, you want to know the signature was produced on the plaintext to which it is attached:
This might sound obvious for some but: Be aware, rsautl verify just decrypts the file signature. The output of this call is guaranteed to be produced by the owner of the private key, but beside that nothing else is being checked. So to actually verify the consistency of data.txt you have to regenerate the digest and then compare it against the output of openssl rsautl -verify.
Verifying that the owner of the private key does vouch for data.txt:
openssl dgst -sha256 -verify publickey.pem -signature signature data.txt
For this operation, openssl requires the public key, the signature, and the message.

To digitally sign document in openssl it will work
For this first your certificate should be trusted
it would be look like this
-----BEGIN TRUSTED CERTIFICATE-----
MIIDbjCCAlYCCQCOyunl25ProDANBgkqhkiG9w0BAQUFADB5MQswCQYDVQQGEwJJ
...
-----END TRUSTED CERTIFICATE-----
Then use following command
smime -sign -signer certificate.pem -inkey private.key -in test.txt \
-out test1.txt -from ashish -to singhal

Related

openssl self-signed certificate verify failed

Background: I create a self-made certificate and use the private key to sign some text.And then, use the self made certificate verify the signature.But I cannot verify successful.Here is my process.
# create Rsa public/private key
openssl genrsa -out private.key 2048
# generate the certificate
openssl req -x509 -days 3650 -key private.key -out ca.csr
# generate text message
echo 'hello' > text
# sign text
openssl smime -sign -inkey private.key -signer ca.csr -in text -outform PEM -out signature
# verify signature
openssl smime -verify -noverify -content text -certfile ca.csr -inform PEM -in signature -signer ca.csr
hello
Verification failure
139927005472576:error:21071065:PKCS7 routines:PKCS7_signatureVerify:digest failure:crypto/pkcs7/pk7_doit.c:1011:
139927005472576:error:21075069:PKCS7 routines:PKCS7_verify:signature failure:crypto/pkcs7/pk7_smime.c:353:
what's wrong with my verification process.
In addition, if verify without -noverify option, which is in line with expectations
# verify signature
openssl smime -verify -content text -certfile ca.csr -inform PEM -in signature -signer ca.csr
Verification failure
139636965443472:error:21075075:PKCS7 routines:PKCS7_verify:certificate verify error:pk7_smime.c:336:Verify error:self signed certificate

Open SSL digital signature unable to load key file

I'm looking to create an example of creating a document, digitally signing it, and verifying it. All works fine until I try and verify the signature, all I get is unable to load key file
Create a document, which needs an agreement (signature):
echo I, Bob, promise to pay Mark £1000 by 1/1/2020 > contract.txt
Generate a private key:
openssl genpkey -algorithm RSA -out private_key.pem -pkeyopt rsa_keygen_bits:2048
Generate the public key from the private key:
openssl rsa -in private_key.pem -RSAPublicKey_out -out public_key.pem
Digitally sign the document:
openssl dgst -sha256 -hex -sign private_key.pem -out signature.sign contract.txt
Then if we view the contents of signature.sign:
RSA-SHA256(contract.txt)= 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
To verify the signature:
openssl dgst -sha256 -hex -verify public_key.pem -signature signature.sign contract.txt
Full script:
echo I, Bob, promise to pay Mark £1000 by 1/1/2020 > contract.txt
openssl genpkey -algorithm RSA -out private_key.pem -pkeyopt rsa_keygen_bits:2048
openssl rsa -in private_key.pem -RSAPublicKey_out -out public_key.pem
openssl dgst -sha256 -sign private_key.pem -out signature contract.txt
openssl dgst -sha256 -verify public_key.pem -signature signature contract.txt
Thank you!

Data verification with openssl smime fails

I am using openssl smime to sign and verify data.
To sign text file using openssl I sue the following command:
openssl smime -sign -in sample.txt -out mail.msg -signer cert.pem -inkey key.pem
Then I proceed to verification:
openssl smime -verify -in mail.msg -CAfile allCA.pem
The verification succeed.
My problem is that I have an external tool that performs the verification using the following command:
openssl smime -verify -in mail.msg -inform DER -CAfile allCA.pem
How to sign my txt file so it can be verified with the previous command ?
What I've tried so far:
openssl smime -sign -in sample.txt -out mail.msg -outform DER -signer cert.pem -inkey key.pem
But I get an error when trying to verify my mail:
Verification failure
140204331579208:error:2107507A:PKCS7 routines:PKCS7_verify:no content:pk7_smime.c:291:
The way you call sign operation creates detached signature so you would need to pass -content sample.txt to verify command. However, it is possible to create structure that encapsulates message together with signature (-nodetach parameter).
This is the sign command you are looking for:
openssl smime -sign -in data.dat -out mail.msg -signer cert.pem -inkey key.pem -outform DER -nodetach

No certificate matches private key while generating .p12 file

I have successfully generated .p12 file but I got a message which is a follows:
C:\OpenSSL-Win32\bin>openssl pkcs12 -export -inkey mykey.key -in exported.pem -out myfile.p12
Loading 'screen' into random state - done
No certificate matches private key
Could anyone tell me what is this error all about?
Also, the size of the file myfile.p12 is 0KB and when I tried to open it, I got the following message in a small window with OK button:
`Invalid Public Key Security Object File
This file is invalid for use as the following: Personal Information Exchange `
Please clarify.
Thanks
Source
OpenSSL says no certificate matches private key when the certificate is DER-encoded. Just change it to PEM encoding before creating the PKCS#12.
Create key pair :
openssl genrsa -out aps_development.key 2048
Create CSR : openssl req -new -sha256 -key aps_development.key -out aps_development.csr
Upload the CSR to developer portal to get the certificate aps_development.cer
Convert the certificate: openssl x509 -inform DER -outform PEM -in aps_development.cer -out aps_development.pem
Build the PKCS#12: openssl pkcs12 -inkey aps_development.key -in aps_development.pem -export -out aps_development.p12
I also had exactly same issue. Below two commands worked like a charm.
cat domain.crt intermediate.crt ca.crt > bundle.crt
openssl pkcs12 -export -out cert.pfx -inkey key -in bundle.crt
In my case, I'd actually specified the wrong certificate -- i.e. the certificate was for one system, and the private key for another. So the error message was spot-on!
Use these commands to compare the RSA Public-Key component of your CSR to that of the private key.
Key: openssl pkey -text_pub -in file.key -noout
CSR: openssl req -in file.csr -noout -text
These must match for 'openssl pkcs12' to create the export file.

Convert .pem to .crt and .key

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