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I have a PEM format certificate which contains all the headers in ASCII/UTF-8 text. I would like to output just the certificate itself. In other words the portion between and inclusive of:

-----BEGIN CERTIFICATE-----

and 

-----END CERTIFICATE-----

I can do this by simply cutting and pasting from the source pem file. However, I would like to do this using OpenSSL. I have looked at the various -text -certopt X but none that I have tried give just the certificate portion.

Is there any way of outputting just the encoded certificate using OpenSSL? How is it done?

jww
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James B. Byrne
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  • Also see [Bash working code to delete first or last line from file](http://stackoverflow.com/a/14913430/608639). – jww Nov 02 '16 at 06:33

4 Answers4

8

Get just the certificate portion from an openssl pem file

Don't use OpenSSL. Instead, use cat, awk, sed and redirections.

For example:

$ ls *.pem
DigiCertHighAssuranceEVRootCA.pem

$ cat DigiCertHighAssuranceEVRootCA.pem 
-----BEGIN CERTIFICATE-----
MIIDxTCCAq2gAwIBAgIQAqxcJmoLQJuPC3nyrkYldzANBgkqhkiG9w0BAQUFADBs
MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
...
Yzi9RKR/5CYrCsSXaQ3pjOLAEFe4yHYSkVXySGnYvCoCWw9E1CAx2/S6cCZdkGCe
vEsXCS+0yx5DaMkHJ8HSXPfqIbloEpw8nL+e/IBcm2PN7EeqJSdnoDfzAIJ9VNep
+OkuE6N36B9K
-----END CERTIFICATE-----

Then, whack the first line:

$ cat DigiCertHighAssuranceEVRootCA.pem | sed '1,1d'
MIIDxTCCAq2gAwIBAgIQAqxcJmoLQJuPC3nyrkYldzANBgkqhkiG9w0BAQUFADBs
MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
...

And whack the last line:

$ cat DigiCertHighAssuranceEVRootCA.pem | sed '$ d'
...
Yzi9RKR/5CYrCsSXaQ3pjOLAEFe4yHYSkVXySGnYvCoCWw9E1CAx2/S6cCZdkGCe
vEsXCS+0yx5DaMkHJ8HSXPfqIbloEpw8nL+e/IBcm2PN7EeqJSdnoDfzAIJ9VNep
+OkuE6N36B9K

Put them together:

$ cat DigiCertHighAssuranceEVRootCA.pem | sed '1,1d' | sed '$ d'
MIIDxTCCAq2gAwIBAgIQAqxcJmoLQJuPC3nyrkYldzANBgkqhkiG9w0BAQUFADBs
MQswCQYDVQQGEwJVUzEVMBMGA1UEChMMRGlnaUNlcnQgSW5jMRkwFwYDVQQLExB3
...
Yzi9RKR/5CYrCsSXaQ3pjOLAEFe4yHYSkVXySGnYvCoCWw9E1CAx2/S6cCZdkGCe
vEsXCS+0yx5DaMkHJ8HSXPfqIbloEpw8nL+e/IBcm2PN7EeqJSdnoDfzAIJ9VNep
+OkuE6N36B9K

Finally, you can fold the sed commands by sparating the separate commands with a semi-colon:

$ cat DigiCertHighAssuranceEVRootCA.pem | sed '1,1d;$ d'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Now, I'm not sure what you were trying to do with -certopt X, so take this with a grain of salt... To print the certificate in readable form, use -text -noout:

$ cat DigiCertHighAssuranceEVRootCA.pem | openssl x509 -text -noout
Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number:
            02:ac:5c:26:6a:0b:40:9b:8f:0b:79:f2:ae:46:25:77
    Signature Algorithm: sha1WithRSAEncryption
        Issuer: C = US, O = DigiCert Inc, OU = www.digicert.com, CN = DigiCert High Assurance EV Root CA
        Validity
            Not Before: Nov 10 00:00:00 2006 GMT
            Not After : Nov 10 00:00:00 2031 GMT
        Subject: C = US, O = DigiCert Inc, OU = www.digicert.com, CN = DigiCert High Assurance EV Root CA
        Subject Public Key Info:
            Public Key Algorithm: rsaEncryption
                Public-Key: (2048 bit)
                Modulus:
                    00:c6:cc:e5:73:e6:fb:d4:bb:e5:2d:2d:32:a6:df:
                    e5:81:3f:c9:cd:25:49:b6:71:2a:c3:d5:94:34:67:
                    a2:0a:1c:b0:5f:69:a6:40:b1:c4:b7:b2:8f:d0:98:
                    a4:a9:41:59:3a:d3:dc:94:d6:3c:db:74:38:a4:4a:
                    cc:4d:25:82:f7:4a:a5:53:12:38:ee:f3:49:6d:71:
                    91:7e:63:b6:ab:a6:5f:c3:a4:84:f8:4f:62:51:be:
                    f8:c5:ec:db:38:92:e3:06:e5:08:91:0c:c4:28:41:
                    55:fb:cb:5a:89:15:7e:71:e8:35:bf:4d:72:09:3d:
                    be:3a:38:50:5b:77:31:1b:8d:b3:c7:24:45:9a:a7:
                    ac:6d:00:14:5a:04:b7:ba:13:eb:51:0a:98:41:41:
                    22:4e:65:61:87:81:41:50:a6:79:5c:89:de:19:4a:
                    57:d5:2e:e6:5d:1c:53:2c:7e:98:cd:1a:06:16:a4:
                    68:73:d0:34:04:13:5c:a1:71:d3:5a:7c:55:db:5e:
                    64:e1:37:87:30:56:04:e5:11:b4:29:80:12:f1:79:
                    39:88:a2:02:11:7c:27:66:b7:88:b7:78:f2:ca:0a:
                    a8:38:ab:0a:64:c2:bf:66:5d:95:84:c1:a1:25:1e:
                    87:5d:1a:50:0b:20:12:cc:41:bb:6e:0b:51:38:b8:
                    4b:cb
                Exponent: 65537 (0x10001)
        X509v3 extensions:
            X509v3 Key Usage: critical
                Digital Signature, Certificate Sign, CRL Sign
            X509v3 Basic Constraints: critical
                CA:TRUE
            X509v3 Subject Key Identifier: 
                B1:3E:C3:69:03:F8:BF:47:01:D4:98:26:1A:08:02:EF:63:64:2B:C3
            X509v3 Authority Key Identifier: 
                keyid:B1:3E:C3:69:03:F8:BF:47:01:D4:98:26:1A:08:02:EF:63:64:2B:C3

    Signature Algorithm: sha1WithRSAEncryption
         1c:1a:06:97:dc:d7:9c:9f:3c:88:66:06:08:57:21:db:21:47:
         f8:2a:67:aa:bf:18:32:76:40:10:57:c1:8a:f3:7a:d9:11:65:
         8e:35:fa:9e:fc:45:b5:9e:d9:4c:31:4b:b8:91:e8:43:2c:8e:
         b3:78:ce:db:e3:53:79:71:d6:e5:21:94:01:da:55:87:9a:24:
         64:f6:8a:66:cc:de:9c:37:cd:a8:34:b1:69:9b:23:c8:9e:78:
         22:2b:70:43:e3:55:47:31:61:19:ef:58:c5:85:2f:4e:30:f6:
         a0:31:16:23:c8:e7:e2:65:16:33:cb:bf:1a:1b:a0:3d:f8:ca:
         5e:8b:31:8b:60:08:89:2d:0c:06:5c:52:b7:c4:f9:0a:98:d1:
         15:5f:9f:12:be:7c:36:63:38:bd:44:a4:7f:e4:26:2b:0a:c4:
         97:69:0d:e9:8c:e2:c0:10:57:b8:c8:76:12:91:55:f2:48:69:
         d8:bc:2a:02:5b:0f:44:d4:20:31:db:f4:ba:70:26:5d:90:60:
         9e:bc:4b:17:09:2f:b4:cb:1e:43:68:c9:07:27:c1:d2:5c:f7:
         ea:21:b9:68:12:9c:3c:9c:bf:9e:fc:80:5c:9b:63:cd:ec:47:
         aa:25:27:67:a0:37:f3:00:82:7d:54:d7:a9:f8:e9:2e:13:a3:
         77:e8:1f:4a

You can also use the openssl x509 utility to open the file for you:

$ openssl x509 -in DigiCertHighAssuranceEVRootCA.pem -inform PEM -text -noout
Certificate:
    Data:
        Version: 3 (0x2)
        Serial Number:
            02:ac:5c:26:6a:0b:40:9b:8f:0b:79:f2:ae:46:25:77
    ...

And convert from PEM to DER:

$ openssl x509 -in DigiCertHighAssuranceEVRootCA.pem -inform PEM \
              -out DigiCertHighAssuranceEVRootCA.der -outform DER

$ dumpasn1 DigiCertHighAssuranceEVRootCA.der 
  0 965: SEQUENCE {
  4 685:   SEQUENCE {
  8   3:     [0] {
 10   1:       INTEGER 2
       :       }
 13  16:     INTEGER 02 AC 5C 26 6A 0B 40 9B 8F 0B 79 F2 AE 46 25 77
...

Is there any way of outputting just the encoded certificate using OpenSSL? How is it done?

No. OpenSSL has -outform in addition to -inform. There are three inform's and outform's available: DER, PEM and NET. None of them are naked Base64.

Also see the openssl x509 man page.

jww
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  • I was afraid of that but I thought that I would ask just to be sure. I thought that some combination of `-certopt` modifications to the `-text` option would give the desired result but it seems not to be the case. Although that seems to me an odd omission for the x509 openssl command. I think that the option of outputting a raw encoded certificate would have been a good candidate for the default behaviour rather than being absent altogether. – James B. Byrne Nov 02 '16 at 12:39
  • `openssl x509 -in cert-0-0.pem -inform PEM -text -noout` Worked well for me – Kishan K Aug 16 '23 at 11:53
4

Just even more late. This is as close as possible i guess openssl + base64.

openssl x509 -in cert.pem -outform der | base64 -w 64

s-hal
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0

Just a tad late. I've just needed exactly the same and would prefer not to do the logic in awk, sed or whatever.

openssl x509 -in YOUR_CERTIFICATE.pem -text -certopt no_header,no_pubkey,no_subject,no_issuer,no_signame,no_version,no_serial,no_validity,no_extensions,no_sigdump,no_aux,no_extensions

Don't know if there are other fields that just don't happen to appear in the certificate I've tested this out on. So far though all indications are this does just what you're after.

Phil
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0

Simple solution:

openssl x509 -in cert.pem | sed -e '1d;$d' > just_the_certificate_itself.txt
David Buck
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TFleschenberg
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