openssl-cmp¶

NAME¶

openssl-cmp - Certificate Management Protocol (CMP, RFC 4210) application

SYNOPSIS¶

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]

DESCRIPTION¶

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.

OPTIONS¶

-help
Display a summary of all options
-config filename
Configuration file to use. An empty string "" means none. Default filename is from the environment variable OPENSSL_CONF.
-section names
Section(s) to use within config file defining CMP options. An empty string "" means no specific section. Default is cmp.
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.
-verbosity level
Level of verbosity for logging, error output, etc. 0 = EMERG, 1 = ALERT, 2 = CRIT, 3 = ERR, 4 = WARN, 5 = NOTE, 6 = INFO, 7 = DEBUG, 8 = TRACE. Defaults to 6 = INFO.

Generic message options¶

-cmd ir|cr|kur|p10cr|rr|genm
CMP command to execute. Currently implemented commands are:
- ir - Initialization Request
- cr - Certificate Request
- p10cr - PKCS#10 Certification Request (for legacy support)
- kur - Key Update Request
- rr - Revocation Request
- genm - General Message
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.
-infotype name
Set InfoType name to use for requesting specific info in genm, e.g., signKeyPairTypes.
-geninfo OID:int:N
generalInfo integer values to place in request PKIHeader with given OID, e.g., 1.2.3.4:int:56789.

Certificate enrollment options¶

-newkey filename|uri
The source of the private or public key for the certificate being requested. Defaults to the public key in the PKCS#10 CSR given with the -csr option, the public key of the reference certificate, or the current client key.
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.
-newkeypass arg
Pass phrase source for the key given with the -newkey option. If not given here, the password will be prompted for if needed.
For more information about the format of arg see openssl-passphrase-options(1).
-subject name
X509 Distinguished Name (DN) of subject to use in the requested certificate template. If the NULL-DN ("/") is given then no subject is placed in the template. Default is the subject DN of any PKCS#10 CSR given with the -csr option. For KUR, a further fallback is the subject DN of the reference certificate (see -oldcert) if provided. This fallback is used for IR and CR only if no SANs are set.
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
-issuer name
X509 issuer Distinguished Name (DN) of the CA server to place in the requested certificate template in IR/CR/KUR. If the NULL-DN ("/") is given then no issuer is placed in the template.
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.
-days number
Number of days the new certificate is requested to be valid for, counting from the current time of the host. Also triggers the explicit request that the validity period starts from the current time (as seen by the host).
-reqexts name
Name of section in OpenSSL config file defining certificate request extensions. If the -csr option is present, these extensions augment the extensions contained the given PKCS#10 CSR, overriding any extensions with same OIDs.
-sans spec
One or more IP addresses, DNS names, or URIs separated by commas or whitespace (where in the latter case the whole argument must be enclosed in "...") to add as Subject Alternative Name(s) (SAN) certificate request extension. If the special element "critical" is given the SANs are flagged as critical. Cannot be used if any Subject Alternative Name extension is set via -reqexts.
-san_nodefault
When Subject Alternative Names are not given via -sans nor defined via -reqexts, they are copied by default from the reference certificate (see -oldcert). This can be disabled by giving the -san_nodefault option.
-policies name
Name of section in OpenSSL config file defining policies to be set as certificate request extension. This option cannot be used together with -policy_oids.
-policy_oids names
One or more OID(s), separated by commas and/or whitespace (where in the latter case the whole argument must be enclosed in "...") to add as certificate policies request extension. This option cannot be used together with -policies.
-policy_oids_critical
Flag the policies given with -policy_oids as critical.
-popo number
Proof-of-possession (POPO) method to use for IR/CR/KUR; values: -1..<2> where -1 = NONE, 0 = RAVERIFIED, 1 = SIGNATURE (default), 2 = KEYENC.
Note that a signature-based POPO can only be produced if a private key is provided via the -newkey or -key options.
-csr filename
PKCS#10 CSR in PEM or DER format containing a certificate request. With -cmd p10cr it is used directly in a legacy P10CR message.
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.
-out_trusted filenames|uris
Trusted certificate(s) to use for validating the newly enrolled certificate. During this verification, any certificate status checking is disabled.
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.
-implicit_confirm
Request implicit confirmation of newly enrolled certificates.
-disable_confirm
Do not send certificate confirmation message for newly enrolled certificate without requesting implicit confirmation to cope with broken servers not supporting implicit confirmation correctly. WARNING: This leads to behavior violating RFC 4210.
-certout filename
The file where the newly enrolled certificate should be saved.
-chainout filename
The file where the chain of the newly enrolled certificate should be saved.

Certificate enrollment and revocation options¶

-oldcert filename|uri
The certificate to be updated (i.e., renewed or re-keyed) in Key Update Request (KUR) messages or to be revoked in Revocation Request (RR) messages. For KUR the certificate to be updated defaults to -cert, and the resulting certificate is called reference certificate. For RR the certificate to be revoked can also be specified using -csr.
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.

-revreason number

Set CRLReason to be included in revocation request (RR); values: 0..10 or -1 for none (which is the default).

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)
 }

Message transfer options¶

-server [http[s]://][userinfo@]host[:port][/path][?query][#fragment]
The host domain name or IP address and optionally port of the CMP server to connect to using HTTP(S). IP address may be for v4 or v6, such as 127.0.0.1 or [::1] for localhost. If the host string is an IPv6 address, it must be enclosed in [ and ].
This option excludes -port and -use_mock_srv. It is ignored if -rspin is given with enough filename arguments.
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.
-proxy [http[s]://][userinfo@]host[:port][/path][?query][#fragment]
The HTTP(S) proxy server to use for reaching the CMP server unless -no_proxy applies, see below. If the host string is an IPv6 address, it must be enclosed in [ and ]. The proxy port defaults to 80 or 443 if the scheme is https; apart from that the optional http:// or https:// prefix is ignored (note that TLS may be selected by -tls_used), as well as any path, userinfo, and query, and fragment components. Defaults to the environment variable http_proxy if set, else HTTP_PROXY in case no TLS is used, otherwise https_proxy if set, else HTTPS_PROXY. This option is ignored if -server is not given.
-no_proxy addresses
List of IP addresses and/or DNS names of servers not to use an HTTP(S) proxy for, separated by commas and/or whitespace (where in the latter case the whole argument must be enclosed in "..."). Default is from the environment variable no_proxy if set, else NO_PROXY. This option is ignored if -server is not given.
-recipient name
Distinguished Name (DN) to use in the recipient field of CMP request message headers, i.e., the CMP server (usually the addressed CA).
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.
-path remote_path
HTTP path at the CMP server (aka CMP alias) to use for POST requests. Defaults to any path given with -server, else "/".
-keep_alive value
If the given value is 0 then HTTP connections are not kept open after receiving a response, which is the default behavior for HTTP 1.0. If the value is 1 or 2 then persistent connections are requested. If the value is 2 then persistent connections are required, i.e., in case the server does not grant them an error occurs. The default value is 1, which means preferring to keep the connection open.
-msg_timeout seconds
Number of seconds a CMP request-response message round trip is allowed to take before a timeout error is returned. A value <= 0 means no limitation (waiting indefinitely). Default is to use the -total_timeout setting.
-total_timeout seconds
Maximum total number of seconds a transaction may take, including polling etc. A value <= 0 means no limitation (waiting indefinitely). Default is 0.

Server authentication options¶

-trusted filenames|uris
The certificate(s), typically of root CAs, the client shall use as trust anchors when validating signature-based protection of CMP response messages. This option is ignored if the -srvcert option is given as well. It provides more flexibility than -srvcert because the CMP protection certificate of the server is not pinned but may be any certificate from which a chain to one of the given trust anchors can be constructed.
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.
-untrusted filenames|uris
Non-trusted intermediate CA certificate(s). Any extra certificates given with the -cert option are appended to it. All these certificates may be useful for cert path construction for the own CMP signer certificate (to include in the extraCerts field of request messages) and for the TLS client certificate (if TLS is enabled) as well as for chain building when validating server certificates (checking signature-based CMP message protection) and when validating newly enrolled certificates.
Multiple filenames or URLs may be given, separated by commas and/or whitespace. Each source may contain multiple certificates.
-srvcert filename|uri
The specific CMP server certificate to expect and directly trust (even if it is expired) when verifying signature-based protection of CMP response messages. This pins the accepted server and results in ignoring the -trusted option.
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.
-expect_sender name
Distinguished Name (DN) expected in the sender field of incoming CMP messages. Defaults to the subject DN of the pinned -srvcert, if any.
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.
-ignore_keyusage
Ignore key usage restrictions in CMP signer certificates when validating signature-based protection of incoming CMP messages. By default, digitalSignature must be allowed by CMP signer certificates.
-unprotected_errors
Accept missing or invalid protection of negative responses from the server. This applies to the following message types and contents:
- error messages
- negative certificate responses (IP/CP/KUP)
- negative revocation responses (RP)
- negative PKIConf messages
WARNING: This setting leads to unspecified behavior and it is meant exclusively to allow interoperability with server implementations violating RFC 4210, e.g.:
- section 5.1.3.1 allows exceptions from protecting only for special cases: "There MAY be cases in which the PKIProtection BIT STRING is deliberately not used to protect a message [...] because other protection, external to PKIX, will be applied instead."
- section 5.3.21 is clear on ErrMsgContent: "The CA MUST always sign it with a signature key."
- appendix D.4 shows PKIConf message having protection
-extracertsout filename
The file where to save all certificates contained in the extraCerts field of the last received response message (except for pollRep and PKIConf).
-cacertsout filename
The file where to save any CA certificates contained in the caPubs field of the last received certificate response (i.e., IP, CP, or KUP) message.

Client authentication options¶

-ref value
Reference number/string/value to use as fallback senderKID; this is required if no sender name can be determined from the -cert or <-subject> options and is typically used when authenticating with pre-shared key (password-based MAC).
-secret arg
Provides the source of a secret value to use with MAC-based message protection. This takes precedence over the -cert and -key options. The secret is used for creating MAC-based protection of outgoing messages and for validating incoming messages that have MAC-based protection. The algorithm used by default is Password-Based Message Authentication Code (PBM) as defined in RFC 4210 section 5.1.3.1.
For more information about the format of arg see openssl-passphrase-options(1).
-cert filename|uri
The client's current CMP signer certificate. Requires the corresponding key to be given with -key.
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.
-own_trusted filenames|uris
If this list of certificates is provided then the chain built for the client-side CMP signer certificate given with the -cert option is verified using the given certificates as trust anchors.
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.
-key filename|uri
The corresponding private key file for the client's current certificate given in the -cert option. This will be used for signature-based message protection unless the -secret option indicating MAC-based protection or -unprotected_requests is given.
It is also used as a fallback for the -newkey option with IR/CR/KUR messages.
-keypass arg
Pass phrase source for the private key given with the -key option. Also used for -cert and -oldcert in case it is an encrypted PKCS#12 file. If not given here, the password will be prompted for if needed.
For more information about the format of arg see openssl-passphrase-options(1).
-digest name
Specifies name of supported digest to use in RFC 4210's MSG_SIG_ALG and as the one-way function (OWF) in MSG_MAC_ALG. If applicable, this is used for message protection and proof-of-possession (POPO) signatures. To see the list of supported digests, use openssl list -digest-commands. Defaults to sha256.
-mac name
Specifies the name of the MAC algorithm in MSG_MAC_ALG. To get the names of supported MAC algorithms use openssl list -mac-algorithms and possibly combine such a name with the name of a supported digest algorithm, e.g., hmacWithSHA256. Defaults to hmac-sha1 as per RFC 4210.
-extracerts filenames|uris
Certificates to append in the extraCerts field when sending messages. They can be used as the default CMP signer certificate chain to include.
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.
-unprotected_requests
Send request messages without CMP-level protection.

Credentials format options¶

-certform PEM|DER
File format to use when saving a certificate to a file. Default value is PEM.
-keyform PEM|DER|P12|ENGINE
The format of the key input; unspecified by default. See "Format Options" in openssl(1) for details.
-otherpass arg
Pass phrase source for certificate given with the -trusted, -untrusted, -own_trusted, -srvcert, -out_trusted, -extracerts, -srv_trusted, -srv_untrusted, -rsp_extracerts, -rsp_capubs, -tls_extra, and -tls_trusted options. If not given here, the password will be prompted for if needed.
For more information about the format of arg see openssl-passphrase-options(1).
-engine id
See "Engine Options" in openssl(1). This option is deprecated.
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.

Provider options¶

-provider name
-provider-path path
-propquery propq
See "Provider Options" in openssl(1), provider(7), and property(7).

Random state options¶

-rand files, -writerand file
See "Random State Options" in openssl(1) for details.

TLS connection options¶

-tls_used
Enable using TLS (even when other TLS-related options are not set) for message exchange with CMP server via HTTP. This option is not supported with the -port option. It is ignored if the -server option is not given or -use_mock_srv is given or -rspin is given with enough filename arguments.
The following TLS-related options are ignored if -tls_used is not given or does not take effect.
-tls_cert filename|uri
Client's TLS certificate. If the source includes further certs they are used (along with -untrusted certs) for constructing the client cert chain provided to the TLS server.
-tls_key filename|uri
Private key for the client's TLS certificate.
-tls_keypass arg
Pass phrase source for client's private TLS key -tls_key. Also used for -tls_cert in case it is an encrypted PKCS#12 file. If not given here, the password will be prompted for if needed.
For more information about the format of arg see openssl-passphrase-options(1).
-tls_extra filenames|uris
Extra certificates to provide to TLS server during TLS handshake
-tls_trusted filenames|uris
Trusted certificate(s) to use for validating the TLS server certificate. This implies hostname validation.
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.
-tls_host name
Address to be checked during hostname validation. This may be a DNS name or an IP address. If not given it defaults to the -server address.

Client-side debugging options¶

-batch
Do not interactively prompt for input, for instance when a password is needed. This can be useful for batch processing and testing.
-repeat number
Invoke the command the given positive number of times with the same parameters. Default is one invocation.
-reqin filenames
Take the sequence of CMP requests to send to the server from the given file(s) rather than from the sequence of requests produced internally.
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).
-reqin_new_tid
Use a fresh transactionID for CMP request messages read using -reqin, which causes their reprotection (if protecting requests is required). This may be needed in case the sequence of requests is reused and the CMP server complains that the transaction ID has already been used.
-reqout filenames
Save the sequence of CMP requests created by the client to the given file(s). These requests are not sent to the server if the -reqin option is used, too.
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.
-rspin filenames
Process the sequence of CMP responses provided in the given file(s), not contacting any given server, as long as enough filenames are provided to complete the transaction.
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.
-rspout filenames
Save the sequence of actually used CMP responses to the given file(s). These have been received from the server unless -rspin takes effect.
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.
-use_mock_srv
Test the client using the internal CMP server mock-up at API level, bypassing socket-based transfer via HTTP. This excludes the -server and -port options.

Mock server options¶

-port number
Act as HTTP-based CMP server mock-up listening on the given local port. The client may address the server via, e.g., 127.0.0.1 or [::1]. This option excludes the -server and -use_mock_srv options. The -rspin, -rspout, -reqin, and -reqout options so far are not supported in this mode.
-max_msgs number
Maximum number of CMP (request) messages the CMP HTTP server mock-up should handle, which must be nonnegative. The default value is 0, which means that no limit is imposed. In any case the server terminates on internal errors, but not when it detects a CMP-level error that it can successfully answer with an error message.
-srv_ref value
Reference value to use as senderKID of server in case no -srv_cert is given.
-srv_secret arg
Password source for server authentication with a pre-shared key (secret).
-srv_cert filename|uri
Certificate of the server.
-srv_key filename|uri
Private key used by the server for signing messages.
-srv_keypass arg
Server private key (and cert) file pass phrase source.
-srv_trusted filenames|uris
Trusted certificates for client authentication.
The certificate verification options -verify_hostname, -verify_ip, and -verify_email have no effect on the certificate verification enabled via this option.
-srv_untrusted filenames|uris
Intermediate CA certs that may be useful when validating client certificates.
-rsp_cert filename|uri
Certificate to be returned as mock enrollment result.
-rsp_extracerts filenames|uris
Extra certificates to be included in mock certification responses.
-rsp_capubs filenames|uris
CA certificates to be included in mock Initialization Response (IP) message.
-poll_count number
Number of times the client must poll before receiving a certificate.
-check_after number
The checkAfter value (number of seconds to wait) to include in poll response.
-grant_implicitconf
Grant implicit confirmation of newly enrolled certificate.
-pkistatus number
PKIStatus to be included in server response. Valid range is 0 (accepted) .. 6 (keyUpdateWarning).
-failure number
A single failure info bit number to be included in server response. Valid range is 0 (badAlg) .. 26 (duplicateCertReq).
-failurebits number Number representing failure bits to be included in server response. Valid range is 0 .. 2^27 - 1.
-statusstring arg
Text to be included as status string in server response.
-send_error
Force server to reply with error message.
-send_unprotected
Send response messages without CMP-level protection.
-send_unprot_err
In case of negative responses, server shall send unprotected error messages, certificate responses (IP/CP/KUP), and revocation responses (RP). WARNING: This setting leads to behavior violating RFC 4210.
-accept_unprotected
Accept missing or invalid protection of requests.
-accept_unprot_err
Accept unprotected error messages from client. So far this has no effect because the server does not accept any error messages.
-accept_raverified
Accept RAVERIFED as proof of possession (POPO).

Certificate verification options, for both CMP and TLS¶

-allow_proxy_certs, -attime, -no_check_time, -check_ss_sig, -crl_check, -crl_check_all, -explicit_policy, -extended_crl, -ignore_critical, -inhibit_any, -inhibit_map, -no_alt_chains, -partial_chain, -policy, -policy_check, -policy_print, -purpose, -suiteB_128, -suiteB_128_only, -suiteB_192, -trusted_first, -use_deltas, -auth_level, -verify_depth, -verify_email, -verify_hostname, -verify_ip, -verify_name, -x509_strict -issuer_checks
Set various options of certificate chain verification. See "Verification Options" in openssl-verification-options(1) for details.
The certificate verification options -verify_hostname, -verify_ip, and -verify_email only affect the certificate verification enabled via the -out_trusted option.

NOTES¶

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.

EXAMPLES¶

Simple examples using the default OpenSSL configuration file¶

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

Certificate enrollment¶

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

Certificate update¶

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 information from CMP server¶

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

Using a custom configuration file¶

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

HISTORY¶

The cmp application was added in OpenSSL 3.0.

The -engine option was deprecated in OpenSSL 3.0.

COPYRIGHT¶

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.