| OPENSSL-CMP(1SSL) | OpenSSL | OPENSSL-CMP(1SSL) |
openssl-cmp - Certificate Management Protocol (CMP, RFC 4210) application
openssl cmp [-help] [-config filename] [-section names] [-verbosity level]
Generic message options:
[-cmd ir|cr|kur|p10cr|rr|genm] [-infotype name] [-geninfo OID:int:N]
Certificate enrollment options:
[-newkey filename|uri] [-newkeypass arg] [-subject name] [-issuer name] [-days number] [-reqexts name] [-sans spec] [-san_nodefault] [-policies name] [-policy_oids names] [-policy_oids_critical] [-popo number] [-csr filename] [-out_trusted filenames|uris] [-implicit_confirm] [-disable_confirm] [-certout filename] [-chainout filename]
Certificate enrollment and revocation options:
[-oldcert filename|uri] [-revreason number]
Message transfer options:
[-server [http[s]://][userinfo@]host[:port][/path][?query][#fragment]] [-proxy [http[s]://][userinfo@]host[:port][/path][?query][#fragment]] [-no_proxy addresses] [-recipient name] [-path remote_path] [-keep_alive value] [-msg_timeout seconds] [-total_timeout seconds]
Server authentication options:
[-trusted filenames|uris] [-untrusted filenames|uris] [-srvcert filename|uri] [-expect_sender name] [-ignore_keyusage] [-unprotected_errors] [-extracertsout filename] [-cacertsout filename]
Client authentication and protection options:
[-ref value] [-secret arg] [-cert filename|uri] [-own_trusted filenames|uris] [-key filename|uri] [-keypass arg] [-digest name] [-mac name] [-extracerts filenames|uris] [-unprotected_requests]
Credentials format options:
[-certform PEM|DER] [-keyform PEM|DER|P12|ENGINE] [-otherpass arg] [-engine id] [-provider name] [-provider-path path] [-propquery propq]
Random state options:
[-rand files] [-writerand file]
TLS connection options:
[-tls_used] [-tls_cert filename|uri] [-tls_key filename|uri] [-tls_keypass arg] [-tls_extra filenames|uris] [-tls_trusted filenames|uris] [-tls_host name]
Client-side debugging options:
[-batch] [-repeat number] [-reqin filenames] [-reqin_new_tid] [-reqout filenames] [-rspin filenames] [-rspout filenames] [-use_mock_srv]
Mock server options:
[-port number] [-max_msgs number] [-srv_ref value] [-srv_secret arg] [-srv_cert filename|uri] [-srv_key filename|uri] [-srv_keypass arg] [-srv_trusted filenames|uris] [-srv_untrusted filenames|uris] [-rsp_cert filename|uri] [-rsp_extracerts filenames|uris] [-rsp_capubs filenames|uris] [-poll_count number] [-check_after number] [-grant_implicitconf] [-pkistatus number] [-failure number] [-failurebits number] [-statusstring arg] [-send_error] [-send_unprotected] [-send_unprot_err] [-accept_unprotected] [-accept_unprot_err] [-accept_raverified]
Certificate verification options, for both CMP and TLS:
[-allow_proxy_certs] [-attime timestamp] [-no_check_time] [-check_ss_sig] [-crl_check] [-crl_check_all] [-explicit_policy] [-extended_crl] [-ignore_critical] [-inhibit_any] [-inhibit_map] [-partial_chain] [-policy arg] [-policy_check] [-policy_print] [-purpose purpose] [-suiteB_128] [-suiteB_128_only] [-suiteB_192] [-trusted_first] [-no_alt_chains] [-use_deltas] [-auth_level num] [-verify_depth num] [-verify_email email] [-verify_hostname hostname] [-verify_ip ip] [-verify_name name] [-x509_strict] [-issuer_checks]
The cmp command is a client implementation for the Certificate Management Protocol (CMP) as defined in RFC4210. It can be used to request certificates from a CA server, update their certificates, request certificates to be revoked, and perform other types of CMP requests.
Multiple section names may be given, separated by commas and/or whitespace (where in the latter case the whole argument must be enclosed in "..."). Contents of sections named later may override contents of sections named before. In any case, as usual, the "[default]" section and finally the unnamed section (as far as present) can provide per-option fallback values.
ir requests initialization of an end entity into a PKI hierarchy by issuing a first certificate.
cr requests issuing an additional certificate for an end entity already initialized to the PKI hierarchy.
p10cr requests issuing an additional certificate similarly to cr but using legacy PKCS#10 CSR format.
kur requests a (key) update for an existing certificate.
rr requests revocation of an existing certificate.
genm requests information using a General Message, where optionally included InfoTypeAndValues may be used to state which info is of interest. Upon receipt of the General Response, information about all received ITAV infoTypes is printed to stdout.
The public portion of the key is placed in the certification request.
Unless -cmd p10cr, -popo -1, or -popo 0 is given, the private key will be needed as well to provide the proof of possession (POPO), where the -key option may provide a fallback.
For more information about the format of arg see openssl-passphrase-options(1).
If provided and neither -cert nor -oldcert is given, the subject DN is used as fallback sender of outgoing CMP messages.
The argument must be formatted as /type0=value0/type1=value1/type2=.... Special characters may be escaped by "\" (backslash); whitespace is retained. Empty values are permitted, but the corresponding type will not be included. Giving a single "/" will lead to an empty sequence of RDNs (a NULL-DN). Multi-valued RDNs can be formed by placing a "+" character instead of a "/" between the AttributeValueAssertions (AVAs) that specify the members of the set. Example:
"/DC=org/DC=OpenSSL/DC=users/UID=123456+CN=John Doe"
If provided and neither -recipient nor -srvcert is given, the issuer DN is used as fallback recipient of outgoing CMP messages.
The argument must be formatted as /type0=value0/type1=value1/type2=.... For details see the description of the -subject option.
Note that a signature-based POPO can only be produced if a private key is provided via the -newkey or -key options.
When used with -cmd ir, cr, or kur, it is transformed into the respective regular CMP request. In this case, a private key must be provided (with -newkey or -key) for the proof of possession (unless -popo -1 or -popo 0 is used) and the respective public key is placed in the certification request (rather than taking over the public key contained in the PKCS#10 CSR).
PKCS#10 CSR input may also be used with -cmd rr to specify the certificate to be revoked via the included subject name and public key.
Multiple sources may be given, separated by commas and/or whitespace (where in the latter case the whole argument must be enclosed in "..."). Each source may contain multiple certificates.
The certificate verification options -verify_hostname, -verify_ip, and -verify_email only affect the certificate verification enabled via this option.
The reference certificate, if any, is also used for deriving default subject DN and Subject Alternative Names and the default issuer entry in the requested certificate template of an IR/CR/KUR. Its public key is used as a fallback in the template of certification requests. Its subject is used as sender of outgoing messages if -cert is not given. Its issuer is used as default recipient in CMP message headers if neither -recipient, -srvcert, nor -issuer is given.
Reason numbers defined in RFC 5280 are:
CRLReason ::= ENUMERATED {
unspecified (0),
keyCompromise (1),
cACompromise (2),
affiliationChanged (3),
superseded (4),
cessationOfOperation (5),
certificateHold (6),
-- value 7 is not used
removeFromCRL (8),
privilegeWithdrawn (9),
aACompromise (10)
}
The scheme "https" may be given only if the -tls_used option is used. In this case the default port is 443, else 80. The optional userinfo and fragment components are ignored. Any given query component is handled as part of the path component. If a path is included it provides the default value for the -path option.
The recipient field in the header of a CMP message is mandatory. If not given explicitly the recipient is determined in the following order: the subject of the CMP server certificate given with the -srvcert option, the -issuer option, the issuer of the certificate given with the -oldcert option, the issuer of the CMP client certificate (-cert option), as far as any of those is present, else the NULL-DN as last resort.
The argument must be formatted as /type0=value0/type1=value1/type2=.... For details see the description of the -subject option.
If none of -trusted, -srvcert, and -secret is given, message validation errors will be thrown unless -unprotected_errors permits an exception.
Multiple sources may be given, separated by commas and/or whitespace (where in the latter case the whole argument must be enclosed in "..."). Each source may contain multiple certificates.
The certificate verification options -verify_hostname, -verify_ip, and -verify_email have no effect on the certificate verification enabled via this option.
Multiple filenames or URLs may be given, separated by commas and/or whitespace. Each source may contain multiple certificates.
If set, the subject of the certificate is also used as default value for the recipient of CMP requests and as default value for the expected sender of CMP responses.
This can be used to make sure that only a particular entity is accepted as CMP message signer, and attackers are not able to use arbitrary certificates of a trusted PKI hierarchy to fraudulently pose as a CMP server. Note that this option gives slightly more freedom than setting the -srvcert, which pins the server to the holder of a particular certificate, while the expected sender name will continue to match after updates of the server cert.
The argument must be formatted as /type0=value0/type1=value1/type2=.... For details see the description of the -subject option.
WARNING: This setting leads to unspecified behavior and it is meant exclusively to allow interoperability with server implementations violating RFC 4210, e.g.:
For more information about the format of arg see openssl-passphrase-options(1).
The subject and the public key contained in this certificate serve as fallback values in the certificate template of IR/CR/KUR messages.
The subject of this certificate will be used as sender of outgoing CMP messages, while the subject of -oldcert or -subjectName may provide fallback values.
The issuer of this certificate is used as one of the recipient fallback values and as fallback issuer entry in the certificate template of IR/CR/KUR messages.
When performing signature-based message protection, this "protection certificate", also called "signer certificate", will be included first in the extraCerts field of outgoing messages and the signature is done with the corresponding key. In Initialization Request (IR) messages this can be used for authenticating using an external entity certificate as defined in appendix E.7 of RFC 4210.
For Key Update Request (KUR) messages this is also used as the certificate to be updated if the -oldcert option is not given.
If the file includes further certs, they are appended to the untrusted certs because they typically constitute the chain of the client certificate, which is included in the extraCerts field in signature-protected request messages.
Multiple sources may be given, separated by commas and/or whitespace (where in the latter case the whole argument must be enclosed in "..."). Each source may contain multiple certificates.
The certificate verification options -verify_hostname, -verify_ip, and -verify_email have no effect on the certificate verification enabled via this option.
It is also used as a fallback for the -newkey option with IR/CR/KUR messages.
For more information about the format of arg see openssl-passphrase-options(1).
Multiple sources may be given, separated by commas and/or whitespace (where in the latter case the whole argument must be enclosed in "..."). Each source may contain multiple certificates.
For more information about the format of arg see openssl-passphrase-options(1).
As an alternative to using this combination:
-engine {engineid} -key {keyid} -keyform ENGINE
... it's also possible to just give the key ID in URI form to -key, like this:
-key org.openssl.engine:{engineid}:{keyid}
This applies to all options specifying keys: -key, -newkey, and -tls_key.
The following TLS-related options are ignored if -tls_used is not given or does not take effect.
For more information about the format of arg see openssl-passphrase-options(1).
Multiple sources may be given, separated by commas and/or whitespace (where in the latter case the whole argument must be enclosed in "..."). Each source may contain multiple certificates.
The certificate verification options -verify_hostname, -verify_ip, and -verify_email have no effect on the certificate verification enabled via this option.
This option is ignored if the -rspin option is given because in the latter case no requests are actually sent.
Multiple filenames may be given, separated by commas and/or whitespace (where in the latter case the whole argument must be enclosed in "...").
The files are read as far as needed to complete the transaction and filenames have been provided. If more requests are needed, the remaining ones are taken from the items at the respective position in the sequence of requests produced internally.
The client needs to update the recipNonce field in the given requests (except for the first one) in order to satisfy the checks to be performed by the server. This causes re-protection (if protecting requests is required).
Multiple filenames may be given, separated by commas and/or whitespace.
Files are written as far as needed to save the transaction and filenames have been provided. If the transaction contains more requests, the remaining ones are not saved.
Multiple filenames may be given, separated by commas and/or whitespace.
Any server specified via the -server or -use_mock_srv options is contacted only if more responses are needed to complete the transaction. In this case the transaction will fail unless the server has been prepared to continue the already started transaction.
Multiple filenames may be given, separated by commas and/or whitespace.
Files are written as far as needed to save the responses contained in the transaction and filenames have been provided. If the transaction contains more responses, the remaining ones are not saved.
The certificate verification options -verify_hostname, -verify_ip, and -verify_email have no effect on the certificate verification enabled via this option.
The certificate verification options -verify_hostname, -verify_ip, and -verify_email only affect the certificate verification enabled via the -out_trusted option.
When a client obtains from a CMP server CA certificates that it is going to trust, for instance via the "caPubs" field of a certificate response, authentication of the CMP server is particularly critical. So special care must be taken setting up server authentication using -trusted and related options for certificate-based authentication or -secret for MAC-based protection.
When setting up CMP configurations and experimenting with enrollment options typically various errors occur until the configuration is correct and complete. When the CMP server reports an error the client will by default check the protection of the CMP response message. Yet some CMP services tend not to protect negative responses. In this case the client will reject them, and thus their contents are not shown although they usually contain hints that would be helpful for diagnostics. For assisting in such cases the CMP client offers a workaround via the -unprotected_errors option, which allows accepting such negative messages.
This CMP client implementation comes with demonstrative CMP sections in the example configuration file openssl/apps/openssl.cnf, which can be used to interact conveniently with the Insta Demo CA.
In order to enroll an initial certificate from that CA it is sufficient to issue the following shell commands.
export OPENSSL_CONF=/path/to/openssl/apps/openssl.cnf
openssl genrsa -out insta.priv.pem openssl cmp -section insta
This should produce the file insta.cert.pem containing a new certificate for the private key held in insta.priv.pem. It can be viewed using, e.g.,
openssl x509 -noout -text -in insta.cert.pem
In case the network setup requires using an HTTP proxy it may be given as usual via the environment variable http_proxy or via the -proxy option in the configuration file or the CMP command-line argument -proxy, for example
-proxy http://192.168.1.1:8080
In the Insta Demo CA scenario both clients and the server may use the pre-shared secret insta and the reference value 3078 to authenticate to each other.
Alternatively, CMP messages may be protected in signature-based manner, where the trust anchor in this case is insta.ca.crt and the client may use any certificate already obtained from that CA, as specified in the [signature] section of the example configuration. This can be used in combination with the [insta] section simply by
openssl cmp -section insta,signature
By default the CMP IR message type is used, yet CR works equally here. This may be specified directly at the command line:
openssl cmp -section insta -cmd cr
or by referencing in addition the [cr] section of the example configuration:
openssl cmp -section insta,cr
In order to update the enrolled certificate one may call
openssl cmp -section insta,kur
using MAC-based protection with PBM or
openssl cmp -section insta,kur,signature
using signature-based protection.
In a similar way any previously enrolled certificate may be revoked by
openssl cmp -section insta,rr -trusted insta.ca.crt
or
openssl cmp -section insta,rr,signature
Many more options can be given in the configuration file and/or on the command line. For instance, the -reqexts CLI option may refer to a section in the configuration file defining X.509 extensions to use in certificate requests, such as "v3_req" in openssl/apps/openssl.cnf:
openssl cmp -section insta,cr -reqexts v3_req
The following examples do not make use of a configuration file at first. They assume that a CMP server can be contacted on the local TCP port 80 and accepts requests under the alias /pkix/.
For enrolling its very first certificate the client generates a client key and sends an initial request message to the local CMP server using a pre-shared secret key for mutual authentication. In this example the client does not have the CA certificate yet, so we specify the name of the CA with the -recipient option and save any CA certificates that we may receive in the "capubs.pem" file.
In below command line usage examples the "\" at line ends is used just for formatting; each of the command invocations should be on a single line.
openssl genrsa -out cl_key.pem
openssl cmp -cmd ir -server 127.0.0.1:80/pkix/ -recipient "/CN=CMPserver" \
-ref 1234 -secret pass:1234-5678 \
-newkey cl_key.pem -subject "/CN=MyName" \
-cacertsout capubs.pem -certout cl_cert.pem
Then, when the client certificate and its related key pair needs to be updated, the client can send a key update request taking the certs in "capubs.pem" as trusted for authenticating the server and using the previous cert and key for its own authentication. Then it can start using the new cert and key.
openssl genrsa -out cl_key_new.pem
openssl cmp -cmd kur -server 127.0.0.1:80/pkix/ \
-trusted capubs.pem \
-cert cl_cert.pem -key cl_key.pem \
-newkey cl_key_new.pem -certout cl_cert.pem
cp cl_key_new.pem cl_key.pem
This command sequence can be repeated as often as needed.
Requesting "all relevant information" with an empty General Message. This prints information about all received ITAV infoTypes to stdout.
openssl cmp -cmd genm -server 127.0.0.1/pkix/ -recipient "/CN=CMPserver" \
-ref 1234 -secret pass:1234-5678
For CMP client invocations, in particular for certificate enrollment, usually many parameters need to be set, which is tedious and error-prone to do on the command line. Therefore, the client offers the possibility to read options from sections of the OpenSSL config file, usually called openssl.cnf. The values found there can still be extended and even overridden by any subsequently loaded sections and on the command line.
After including in the configuration file the following sections:
[cmp] server = 127.0.0.1 path = pkix/ trusted = capubs.pem cert = cl_cert.pem key = cl_key.pem newkey = cl_key.pem certout = cl_cert.pem [init] recipient = "/CN=CMPserver" trusted = cert = key = ref = 1234 secret = pass:1234-5678-1234-567 subject = "/CN=MyName" cacertsout = capubs.pem
the above enrollment transactions reduce to
openssl cmp -section cmp,init openssl cmp -cmd kur -newkey cl_key_new.pem
and the above transaction using a general message reduces to
openssl cmp -section cmp,init -cmd genm
openssl-genrsa(1), openssl-ecparam(1), openssl-list(1), openssl-req(1), openssl-x509(1), x509v3_config(5)
The cmp application was added in OpenSSL 3.0.
The -engine option was deprecated in OpenSSL 3.0.
Copyright 2007-2023 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use this file except in compliance with the License. You can obtain a copy in the file LICENSE in the source distribution or at <https://www.openssl.org/source/license.html>.
| 2023-10-23 | 3.0.11 |