# phpman > man > OPENSSL-CMS(1SSL)

[OPENSSL-CMS(1SSL)](https://www.chedong.com/phpMan.php/man/OPENSSL-CMS/1SSL/markdown)                              OpenSSL                             [OPENSSL-CMS(1SSL)](https://www.chedong.com/phpMan.php/man/OPENSSL-CMS/1SSL/markdown)



## NAME
       openssl-cms - CMS command

## SYNOPSIS
       **openssl** **cms** [**-help**]

       General options:

       [**-in** _filename_] [**-out** _filename_] [**-config** _configfile_]

       Operation options:

       [**-encrypt**] [**-decrypt**] [**-sign**] [**-verify**] [**-resign**] [**-sign**___**receipt**] [**-verify**___**receipt** _receipt_]
       [**-digest**___**create**] [**-digest**___**verify**] [**-compress**] [**-uncompress**] [**-EncryptedData**___**encrypt**]
       [**-EncryptedData**___**decrypt**] [**-data**___**create**] [**-data**___**out**] [**-cmsout**]

       File format options:

       [**-inform** **DER**|**PEM**|**SMIME**] [**-outform** **DER**|**PEM**|**SMIME**] [**-rctform** **DER**|**PEM**|**SMIME**] [**-stream**] [**-indef**]
       [**-noindef**] [**-binary**] [**-crlfeol**] [**-asciicrlf**]

       Keys and password options:

       [**-pwri**___**password** _password_] [**-secretkey** _key_] [**-secretkeyid** _id_] [**-inkey** _filename_|_uri_] [**-passin**
       _arg_] [**-keyopt** _name_:_parameter_] [**-keyform** **DER**|**PEM**|**P12**|**ENGINE**] [**-engine** _id_] [**-provider** _name_]
       [**-provider-path** _path_] [**-propquery** _propq_] [**-rand** _files_] [**-writerand** _file_]

       Encryption options:

       [**-originator** _file_] [**-recip** _file_] [_recipient-cert_ ...]  [**-**_c_c_i_i_p_p_h_h_e_e_r_r] [**-wrap** _cipher_]
       [**-aes128-wrap**] [**-aes192-wrap**] [**-aes256-wrap**] [**-des3-wrap**] [**-debug**___**decrypt**]

       Signing options:

       [**-md** _digest_] [**-signer** _file_] [**-certfile** _file_] [**-cades**] [**-nodetach**] [**-nocerts**] [**-noattr**]
       [**-nosmimecap**] [**-receipt**___**request**___**all**] [**-receipt**___**request**___**first**] [**-receipt**___**request**___**from**
       _emailaddress_] [**-receipt**___**request**___**to** _emailaddress_]

       Verification options:

       [**-signer** _file_] [**-content** _filename_] [**-no**___**content**___**verify**] [**-no**___**attr**___**verify**] [**-nosigs**]
       [**-noverify**] [**-nointern**] [**-cades**] [**-verify**___**retcode**] [**-CAfile** _file_] [**-no-CAfile**] [**-CApath** _dir_]
       [**-no-CApath**] [**-CAstore** _uri_] [**-no-CAstore**]

       Output options:

       [**-keyid**] [**-econtent**___**type** _type_] [**-text**] [**-certsout** _file_] [**-to** _addr_] [**-from** _addr_] [**-subject**
       _subj_]

       Printing options:

       [**-noout**] [**-print**] [**-nameopt** _option_] [**-receipt**___**request**___**print**]

       Validation options:

       [**-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
       This command handles data in CMS format such as S/MIME v3.1 email messages.  It can encrypt,
       decrypt, sign, verify, compress, uncompress, and print messages.

## OPTIONS
       There are a number of operation options that set the type of operation to be performed:
       encrypt, decrypt, sign, verify, resign, sign_receipt, verify_receipt, digest_create,
       digest_verify, compress, uncompress, EncryptedData_encrypt, EncryptedData_decrypt,
       data_create, data_out, or cmsout.  The relevance of the other options depends on the
       operation type and their meaning may vary according to it.

### -help
           Print out a usage message.

### General options
### -in
           The input message to be encrypted or signed or the message to be decrypted or verified.

### -out
           The message text that has been decrypted or verified or the output MIME format message
           that has been signed or verified.

### -config
           See "Configuration Option" in [**openssl**(1)](https://www.chedong.com/phpMan.php/man/openssl/1/markdown).

### Operation options
### -encrypt
           Encrypt data for the given recipient certificates. Input file is the message to be
           encrypted. The output file is the encrypted data in MIME format. The actual CMS type is
           **EnvelopedData**.

           Note that no revocation check is done for the recipient cert, so if that key has been
           compromised, others may be able to decrypt the text.

### -decrypt
           Decrypt data using the supplied certificate and private key. Expects encrypted datain
           MIME format for the input file. The decrypted data is written to the output file.

### -sign
           Sign data using the supplied certificate and private key. Input file is the message to be
           signed. The signed data in MIME format is written to the output file.

### -verify
           Verify signed data. Expects a signed data on input and outputs the signed data. Both
           clear text and opaque signing is supported.

### -resign
           Resign a message: take an existing message and one or more new signers.

### -sign
           Generate and output a signed receipt for the supplied message. The input message **must**
           contain a signed receipt request. Functionality is otherwise similar to the **-sign**
           operation.

### -verify
           Verify a signed receipt in filename **receipt**. The input message **must** contain the original
           receipt request. Functionality is otherwise similar to the **-verify** operation.

### -digest
           Create a CMS **DigestedData** type.

### -digest
           Verify a CMS **DigestedData** type and output the content.

### -compress
           Create a CMS **CompressedData** type. OpenSSL must be compiled with **zlib** support for this
           option to work, otherwise it will output an error.

### -uncompress
           Uncompress a CMS **CompressedData** type and output the content. OpenSSL must be compiled
           with **zlib** support for this option to work, otherwise it will output an error.

### -EncryptedData
           Encrypt content using supplied symmetric key and algorithm using a CMS **EncryptedData** type
           and output the content.

### -EncryptedData
           Decrypt content using supplied symmetric key and algorithm using a CMS **EncryptedData** type
           and output the content.

### -data
           Create a CMS **Data** type.

### -data
           **Data** type and output the content.

### -cmsout
           Takes an input message and writes out a PEM encoded CMS structure.

### File format options
### -inform
           The input format of the CMS structure (if one is being read); the default is **SMIME**.  See
           [**openssl-format-options**(1)](https://www.chedong.com/phpMan.php/man/openssl-format-options/1/markdown) for details.

### -outform
           The output format of the CMS structure (if one is being written); the default is **SMIME**.
           See [**openssl-format-options**(1)](https://www.chedong.com/phpMan.php/man/openssl-format-options/1/markdown) for details.

### -rctform
           The signed receipt format for use with the **-receipt**___**verify**; the default is **SMIME**.  See
           [**openssl-format-options**(1)](https://www.chedong.com/phpMan.php/man/openssl-format-options/1/markdown) for details.

### -stream -indef
           The **-stream** and **-indef** options are equivalent and enable streaming I/O for encoding
           operations. This permits single pass processing of data without the need to hold the
           entire contents in memory, potentially supporting very large files. Streaming is
           automatically set for S/MIME signing with detached data if the output format is **SMIME** it
           is currently off by default for all other operations.

### -noindef
           Disable streaming I/O where it would produce and indefinite length constructed encoding.
           This option currently has no effect. In future streaming will be enabled by default on
           all relevant operations and this option will disable it.

### -binary
           Normally the input message is converted to "canonical" format which is effectively using
           CR and LF as end of line: as required by the S/MIME specification. When this option is
           present no translation occurs. This is useful when handling binary data which may not be
           in MIME format.

### -crlfeol
           Normally the output file uses a single **LF** as end of line. When this option is present
           **CRLF** is used instead.

### -asciicrlf
           When signing use ASCII CRLF format canonicalisation. This strips trailing whitespace from
           all lines, deletes trailing blank lines at EOF and sets the encapsulated content type.
           This option is normally used with detached content and an output signature format of DER.
           This option is not normally needed when verifying as it is enabled automatically if the
           encapsulated content format is detected.

### Keys and password options
### -pwri
           Specify password for recipient.

### -secretkey
           Specify symmetric key to use. The key must be supplied in hex format and be consistent
           with the algorithm used. Supported by the **-EncryptedData**___**encrypt** **-EncryptedData**___**decrypt**,
           **-encrypt** and **-decrypt** options. When used with **-encrypt** or **-decrypt** the supplied key is
           used to wrap or unwrap the content encryption key using an AES key in the
           **KEKRecipientInfo** type.

### -secretkeyid
           The key identifier for the supplied symmetric key for **KEKRecipientInfo** type.  This option
           **must** be present if the **-secretkey** option is used with **-encrypt**. With **-decrypt** operations
           the _id_ is used to locate the relevant key if it is not supplied then an attempt is used
           to decrypt any **KEKRecipientInfo** structures.

### -inkey
           The private key to use when signing or decrypting. This must match the corresponding
           certificate. If this option is not specified then the private key must be included in the
           certificate file specified with the **-recip** or **-signer** file. When signing this option can
           be used multiple times to specify successive keys.

### -passin
           The private key password source. For more information about the format of **arg** see
           [**openssl-passphrase-options**(1)](https://www.chedong.com/phpMan.php/man/openssl-passphrase-options/1/markdown).

### -keyopt
           For signing and encryption this option can be used multiple times to set customised
           parameters for the preceding key or certificate. It can currently be used to set RSA-PSS
           for signing, RSA-OAEP for encryption or to modify default parameters for ECDH.

### -keyform
           The format of the private key file; unspecified by default.  See
           [**openssl-format-options**(1)](https://www.chedong.com/phpMan.php/man/openssl-format-options/1/markdown) for details.

### -engine
           See "Engine Options" in [**openssl**(1)](https://www.chedong.com/phpMan.php/man/openssl/1/markdown).  This option is deprecated.

### -provider
### -provider-path
### -propquery
           See "Provider Options" in [**openssl**(1)](https://www.chedong.com/phpMan.php/man/openssl/1/markdown), [**provider**(7)](https://www.chedong.com/phpMan.php/man/provider/7/markdown), and [**property**(7)](https://www.chedong.com/phpMan.php/man/property/7/markdown).

### -rand -writerand
           See "Random State Options" in [**openssl**(1)](https://www.chedong.com/phpMan.php/man/openssl/1/markdown) for details.

### Encryption and decryption options
### -originator
           A certificate of the originator of the encrypted message. Necessary for decryption when
           Key Agreement is in use for a shared key.

### -recip
           When decrypting a message this specifies the certificate of the recipient.  The
           certificate must match one of the recipients of the message.

           When encrypting a message this option may be used multiple times to specify each
           recipient. This form **must** be used if customised parameters are required (for example to
           specify RSA-OAEP).

           Only certificates carrying RSA, Diffie-Hellman or EC keys are supported by this option.

       _recipient-cert_ ...
           This is an alternative to using the **-recip** option when encrypting a message.  One or more
           certificate filennames may be given.

       **-**_c_c_i_i_p_p_h_h_e_e_r_r
           The encryption algorithm to use. For example triple DES (168 bits) - **-des3** or 256 bit AES
           - **-aes256**. Any standard algorithm name (as used by the **EVP**___**get**___**cipherbyname()** function)
           can also be used preceded by a dash, for example **-aes-128-cbc**. See [**openssl-enc**(1)](https://www.chedong.com/phpMan.php/man/openssl-enc/1/markdown) for a
           list of ciphers supported by your version of OpenSSL.

           Currently the AES variants with GCM mode are the only supported AEAD algorithms.

           If not specified triple DES is used. Only used with **-encrypt** and **-EncryptedData**___**create**
           commands.

### -wrap
           Cipher algorithm to use for key wrap when encrypting the message using Key Agreement for
           key transport. The algorithm specified should be suitable for key wrap.

### -aes128-wrap -aes192-wrap -aes256-wrap -des3-wrap
           Use AES128, AES192, AES256, or 3DES-EDE, respectively, to wrap key.  Depending on the
           OpenSSL build options used, **-des3-wrap** may not be supported.

### -debug
           This option sets the **CMS**___**DEBUG**___**DECRYPT** flag. This option should be used with caution: see
           the notes section below.

### Signing options
### -md
           Digest algorithm to use when signing or resigning. If not present then the default digest
           algorithm for the signing key will be used (usually SHA1).

### -signer
           A signing certificate.  When signing or resigning a message, this option can be used
           multiple times if more than one signer is required.

### -certfile
           Allows additional certificates to be specified. When signing these will be included with
           the message. When verifying these will be searched for the signers certificates.  The
           input can be in PEM, DER, or PKCS#12 format.

### -cades
           When used with **-sign**, add an ESS signingCertificate or ESS signingCertificateV2 signed-
           attribute to the SignerInfo, in order to make the signature comply with the requirements
           for a CAdES Basic Electronic Signature (CAdES-BES).

### -nodetach
           When signing a message use opaque signing: this form is more resistant to translation by
           mail relays but it cannot be read by mail agents that do not support S/MIME.  Without
           this option cleartext signing with the MIME type multipart/signed is used.

### -nocerts
           When signing a message the signer's certificate is normally included with this option it
           is excluded. This will reduce the size of the signed message but the verifier must have a
           copy of the signers certificate available locally (passed using the **-certfile** option for
           example).

### -noattr
           Normally when a message is signed a set of attributes are included which include the
           signing time and supported symmetric algorithms. With this option they are not included.

### -nosmimecap
           Exclude the list of supported algorithms from signed attributes, other options such as
           signing time and content type are still included.

### -receipt -receipt
           For **-sign** option include a signed receipt request. Indicate requests should be provided
           by all recipient or first tier recipients (those mailed directly and not from a mailing
           list). Ignored it **-receipt**___**request**___**from** is included.

### -receipt
           For **-sign** option include a signed receipt request. Add an explicit email address where
           receipts should be supplied.

### -receipt
           Add an explicit email address where signed receipts should be sent to. This option **must**
           but supplied if a signed receipt is requested.

### Verification options
### -signer
           If a message has been verified successfully then the signers certificate(s) will be
           written to this file if the verification was successful.

### -content
           This specifies a file containing the detached content for operations taking S/MIME input,
           such as the **-verify** command. This is only usable if the CMS structure is using the
           detached signature form where the content is not included. This option will override any
           content if the input format is S/MIME and it uses the multipart/signed MIME content type.

### -no
           Do not verify signed content signatures.

### -no
           Do not verify signed attribute signatures.

### -nosigs
           Don't verify message signature.

### -noverify
           Do not verify the signers certificate of a signed message.

### -nointern
           When verifying a message normally certificates (if any) included in the message are
           searched for the signing certificate. With this option only the certificates specified in
           the **-certfile** option are used.  The supplied certificates can still be used as untrusted
           CAs however.

### -cades
           When used with **-verify**, require and check signer certificate digest.  See the NOTES
           section for more details.

### -verify
           Exit nonzero on verification failure.

### -CAfile -no-CAfile -CApath -no-CApath -CAstore -no-CAstore
           See "Trusted Certificate Options" in [**openssl-verification-options**(1)](https://www.chedong.com/phpMan.php/man/openssl-verification-options/1/markdown) for details.

### Output options
### -keyid
           Use subject key identifier to identify certificates instead of issuer name and serial
           number. The supplied certificate **must** include a subject key identifier extension.
           Supported by **-sign** and **-encrypt** options.

### -econtent
           Set the encapsulated content type to _type_ if not supplied the **Data** type is used. The _type_
           argument can be any valid OID name in either text or numerical format.

### -text
           This option adds plain text (text/plain) MIME headers to the supplied message if
           encrypting or signing. If decrypting or verifying it strips off text headers: if the
           decrypted or verified message is not of MIME type text/plain then an error occurs.

### -certsout
           Any certificates contained in the input message are written to _file_.

### -to -from -subject
           The relevant email headers. These are included outside the signed portion of a message so
           they may be included manually. If signing then many S/MIME mail clients check the signers
           certificate's email address matches that specified in the From: address.

### Printing options
### -noout
           For the **-cmsout** operation do not output the parsed CMS structure.  This is useful if the
           syntax of the CMS structure is being checked.

### -print
           For the **-cmsout** operation print out all fields of the CMS structure.  This implies
           **-noout**.  This is mainly useful for testing purposes.

### -nameopt
           For the **-cmsout** operation when **-print** option is in use, specifies printing options for
           string fields. For most cases **utf8** is reasonable value.  See
           [**openssl-namedisplay-options**(1)](https://www.chedong.com/phpMan.php/man/openssl-namedisplay-options/1/markdown) for details.

### -receipt
           For the **-verify** operation print out the contents of any signed receipt requests.

### Validation options
### -allow -attime -no -check -crl -crl
### -explicit -extended -ignore -inhibit -inhibit
### -no -partial -policy -policy -policy -purpose -suiteB
### -suiteB -suiteB -trusted -use -auth -verify
### -verify -verify -verify -verify -x509 -issuer
           Set various options of certificate chain verification.  See "Verification Options" in
           [**openssl-verification-options**(1)](https://www.chedong.com/phpMan.php/man/openssl-verification-options/1/markdown) for details.

           Any validation errors cause the command to exit.

## NOTES
       The MIME message must be sent without any blank lines between the headers and the output.
       Some mail programs will automatically add a blank line. Piping the mail directly to sendmail
       is one way to achieve the correct format.

       The supplied message to be signed or encrypted must include the necessary MIME headers or
       many S/MIME clients won't display it properly (if at all). You can use the **-text** option to
       automatically add plain text headers.

       A "signed and encrypted" message is one where a signed message is then encrypted. This can be
       produced by encrypting an already signed message: see the examples section.

       This version of the program only allows one signer per message but it will verify multiple
       signers on received messages. Some S/MIME clients choke if a message contains multiple
       signers. It is possible to sign messages "in parallel" by signing an already signed message.

       The options **-encrypt** and **-decrypt** reflect common usage in S/MIME clients. Strictly speaking
       these process CMS enveloped data: CMS encrypted data is used for other purposes.

       The **-resign** option uses an existing message digest when adding a new signer. This means that
       attributes must be present in at least one existing signer using the same message digest or
       this operation will fail.

       The **-stream** and **-indef** options enable streaming I/O support.  As a result the encoding is BER
       using indefinite length constructed encoding and no longer DER. Streaming is supported for
       the **-encrypt** operation and the **-sign** operation if the content is not detached.

       Streaming is always used for the **-sign** operation with detached data but since the content is
       no longer part of the CMS structure the encoding remains DER.

       If the **-decrypt** option is used without a recipient certificate then an attempt is made to
       locate the recipient by trying each potential recipient in turn using the supplied private
       key. To thwart the MMA attack (Bleichenbacher's attack on PKCS #1 v1.5 RSA padding) all
       recipients are tried whether they succeed or not and if no recipients match the message is
       "decrypted" using a random key which will typically output garbage.  The **-debug**___**decrypt**
       option can be used to disable the MMA attack protection and return an error if no recipient
       can be found: this option should be used with caution. For a fuller description see
       **CMS**___**[decrypt**(3)](https://www.chedong.com/phpMan.php/man/decrypt/3/markdown)).

### CADES BASIC ELECTRONIC SIGNATURE (CADES-BES)
       A CAdES Basic Electronic Signature (CAdES-BES), as defined in the European Standard ETSI EN
       319 122-1 V1.1.1, contains:

       •   The signed user data as defined in CMS (RFC 3852);

       •   Content-type of the EncapsulatedContentInfo value being signed;

       •   Message-digest of the eContent OCTET STRING within encapContentInfo being signed;

       •   An ESS signingCertificate or ESS signingCertificateV2 attribute, as defined in Enhanced
           Security Services (ESS), RFC 2634 and RFC 5035.  An ESS signingCertificate attribute only
           allows for SHA-1 as digest algorithm.  An ESS signingCertificateV2 attribute allows for
           any digest algorithm.

       •   The digital signature value computed on the user data and, when present, on the signed
           attributes.

           NOTE that the **-cades** option applies to the **-sign** or **-verify** operations.  With this
           option, the **-verify** operation also requires that the signingCertificate attribute is
           present and checks that the given identifiers match the verification trust chain built
           during the verification process.

## EXIT CODES
       0   The operation was completely successfully.

       1   An error occurred parsing the command options.

       2   One of the input files could not be read.

       3   An error occurred creating the CMS file or when reading the MIME message.

       4   An error occurred decrypting or verifying the message.

       5   The message was verified correctly but an error occurred writing out the signers
           certificates.

### COMPATIBILITY WITH PKCS#7 FORMAT
       [**openssl-smime**(1)](https://www.chedong.com/phpMan.php/man/openssl-smime/1/markdown) can only process the older **PKCS#7** format.  **openssl** **cms** supports
       Cryptographic Message Syntax format.  Use of some features will result in messages which
       cannot be processed by applications which only support the older format. These are detailed
       below.

       The use of the **-keyid** option with **-sign** or **-encrypt**.

       The **-outform** _PEM_ option uses different headers.

       The **-compress** option.

       The **-secretkey** option when used with **-encrypt**.

       The use of PSS with **-sign**.

       The use of OAEP or non-RSA keys with **-encrypt**.

       Additionally the **-EncryptedData**___**create** and **-data**___**create** type cannot be processed by the older
       [**openssl-smime**(1)](https://www.chedong.com/phpMan.php/man/openssl-smime/1/markdown) command.

## EXAMPLES
       Create a cleartext signed message:

        openssl cms -sign -in message.txt -text -out mail.msg \
               -signer mycert.pem

       Create an opaque signed message

        openssl cms -sign -in message.txt -text -out mail.msg -nodetach \
               -signer mycert.pem

       Create a signed message, include some additional certificates and read the private key from
       another file:

        openssl cms -sign -in in.txt -text -out mail.msg \
               -signer mycert.pem -inkey mykey.pem -certfile mycerts.pem

       Create a signed message with two signers, use key identifier:

        openssl cms -sign -in message.txt -text -out mail.msg \
               -signer mycert.pem -signer othercert.pem -keyid

       Send a signed message under Unix directly to sendmail, including headers:

        openssl cms -sign -in in.txt -text -signer mycert.pem \
               -from <steve@openssl.org> -to someone@somewhere \
               -subject "Signed message" | sendmail someone@somewhere

       Verify a message and extract the signer's certificate if successful:

        openssl cms -verify -in mail.msg -signer user.pem -out signedtext.txt

       Send encrypted mail using triple DES:

        openssl cms -encrypt -in in.txt -from <steve@openssl.org> \
               -to someone@somewhere -subject "Encrypted message" \
               -des3 user.pem -out mail.msg

       Sign and encrypt mail:

        openssl cms -sign -in ml.txt -signer my.pem -text \
               | openssl cms -encrypt -out mail.msg \
               -from <steve@openssl.org> -to someone@somewhere \
               -subject "Signed and Encrypted message" -des3 user.pem

       Note: the encryption command does not include the **-text** option because the message being
       encrypted already has MIME headers.

       Decrypt a message:

        openssl cms -decrypt -in mail.msg -recip mycert.pem -inkey key.pem

       The output from Netscape form signing is a PKCS#7 structure with the detached signature
       format. You can use this program to verify the signature by line wrapping the base64 encoded
       structure and surrounding it with:

        -----BEGIN PKCS7-----
        -----END PKCS7-----

       and using the command,

        openssl cms -verify -inform PEM -in signature.pem -content content.txt

       alternatively you can base64 decode the signature and use

        openssl cms -verify -inform DER -in signature.der -content content.txt

       Create an encrypted message using 128 bit Camellia:

        openssl cms -encrypt -in plain.txt -camellia128 -out mail.msg cert.pem

       Add a signer to an existing message:

        openssl cms -resign -in mail.msg -signer newsign.pem -out mail2.msg

       Sign a message using RSA-PSS:

        openssl cms -sign -in message.txt -text -out mail.msg \
               -signer mycert.pem -keyopt rsa_padding_mode:pss

       Create an encrypted message using RSA-OAEP:

        openssl cms -encrypt -in plain.txt -out mail.msg \
               -recip cert.pem -keyopt rsa_padding_mode:oaep

       Use SHA256 KDF with an ECDH certificate:

        openssl cms -encrypt -in plain.txt -out mail.msg \
               -recip ecdhcert.pem -keyopt ecdh_kdf_md:sha256

       Print CMS signed binary data in human-readable form:

       openssl cms -in signed.cms -binary -inform DER -cmsout -print

## BUGS
       The MIME parser isn't very clever: it seems to handle most messages that I've thrown at it
       but it may choke on others.

       The code currently will only write out the signer's certificate to a file: if the signer has
       a separate encryption certificate this must be manually extracted. There should be some
       heuristic that determines the correct encryption certificate.

       Ideally a database should be maintained of a certificates for each email address.

       The code doesn't currently take note of the permitted symmetric encryption algorithms as
       supplied in the SMIMECapabilities signed attribute. this means the user has to manually
       include the correct encryption algorithm. It should store the list of permitted ciphers in a
       database and only use those.

       No revocation checking is done on the signer's certificate.

## SEE ALSO
       **ossl**___**[store-file**(7)](https://www.chedong.com/phpMan.php/man/store-file/7/markdown)

## HISTORY
       The use of multiple **-signer** options and the **-resign** command were first added in OpenSSL
       1.0.0.

       The **-keyopt** option was added in OpenSSL 1.0.2.

       Support for RSA-OAEP and RSA-PSS was added in OpenSSL 1.0.2.

       The use of non-RSA keys with **-encrypt** and **-decrypt** was added in OpenSSL 1.0.2.

       The -no_alt_chains option was added in OpenSSL 1.0.2b.

       The **-nameopt** option was added in OpenSSL 3.0.0.

       The **-engine** option was deprecated in OpenSSL 3.0.

## COPYRIGHT
       Copyright 2008-2021 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>>.



3.0.2                                        2026-06-02                            [OPENSSL-CMS(1SSL)](https://www.chedong.com/phpMan.php/man/OPENSSL-CMS/1SSL/markdown)
