Provided by: openssl_1.1.1-1ubuntu2_amd64 bug

NAME

       openssl-cms, cms - CMS utility

SYNOPSIS

       openssl cms [-help] [-encrypt] [-decrypt] [-sign] [-verify] [-cmsout] [-resign]
       [-data_create] [-data_out] [-digest_create] [-digest_verify] [-compress] [-uncompress]
       [-EncryptedData_encrypt] [-sign_receipt] [-verify_receipt receipt] [-in filename] [-inform
       SMIME|PEM|DER] [-rctform SMIME|PEM|DER] [-out filename] [-outform SMIME|PEM|DER] [-stream
       -indef -noindef] [-noindef] [-content filename] [-text] [-noout] [-print] [-CAfile file]
       [-CApath dir] [-no-CAfile] [-no-CApath] [-attime timestamp] [-check_ss_sig] [-crl_check]
       [-crl_check_all] [-explicit_policy] [-extended_crl] [-ignore_critical] [-inhibit_any]
       [-inhibit_map] [-no_check_time] [-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] [-md digest] [-cipher] [-nointern] [-noverify] [-nocerts] [-noattr]
       [-nosmimecap] [-binary] [-crlfeol] [-asciicrlf] [-nodetach] [-certfile file] [-certsout
       file] [-signer file] [-recip file] [-keyid] [-receipt_request_all]
       [-receipt_request_first] [-receipt_request_from emailaddress] [-receipt_request_to
       emailaddress] [-receipt_request_print] [-secretkey key] [-secretkeyid id] [-econtent_type
       type] [-inkey file] [-keyopt name:parameter] [-passin arg] [-rand file...]  [-writerand
       file] [cert.pem...]  [-to addr] [-from addr] [-subject subj] [cert.pem]...

DESCRIPTION

       The cms command handles S/MIME v3.1 mail. It can encrypt, decrypt, sign and verify,
       compress and uncompress S/MIME messages.

OPTIONS

       There are fourteen operation options that set the type of operation to be performed. The
       meaning of the other options varies according to the operation type.

       -help
           Print out a usage message.

       -encrypt
           Encrypt mail for the given recipient certificates. Input file is the message to be
           encrypted. The output file is the encrypted mail in MIME format. The actual CMS type
           is <B>EnvelopedData<B>.

           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 mail using the supplied certificate and private key. Expects an encrypted mail
           message in MIME format for the input file. The decrypted mail is written to the output
           file.

       -debug_decrypt
           This option sets the CMS_DEBUG_DECRYPT flag. This option should be used with caution:
           see the notes section below.

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

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

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

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

       -data_create
           Create a CMS Data type.

       -data_out
           Data type and output the content.

       -digest_create
           Create a CMS DigestedData type.

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

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

       -in filename
           The input message to be encrypted or signed or the message to be decrypted or
           verified.

       -inform SMIME|PEM|DER
           This specifies the input format for the CMS structure. The default is SMIME which
           reads an S/MIME format message. PEM and DER format change this to expect PEM and DER
           format CMS structures instead. This currently only affects the input format of the CMS
           structure, if no CMS structure is being input (for example with -encrypt or -sign)
           this option has no effect.

       -rctform SMIME|PEM|DER
           Specify the format for a signed receipt for use with the -receipt_verify operation.

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

       -outform SMIME|PEM|DER
           This specifies the output format for the CMS structure. The default is SMIME which
           writes an S/MIME format message. PEM and DER format change this to write PEM and DER
           format CMS structures instead. This currently only affects the output format of the
           CMS structure, if no CMS structure is being output (for example with -verify or
           -decrypt) this option has no effect.

       -stream -indef -noindef
           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.

       -content filename
           This specifies a file containing the detached content, this is only useful with 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.

       -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.

       -noout
           For the -cmsout operation do not output the parsed CMS structure. This is useful when
           combined with the -print option or if the syntax of the CMS structure is being
           checked.

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

       -CAfile file
           A file containing trusted CA certificates, only used with -verify.

       -CApath dir
           A directory containing trusted CA certificates, only used with -verify. This directory
           must be a standard certificate directory: that is a hash of each subject name (using
           x509 -hash) should be linked to each certificate.

       -no-CAfile
           Do not load the trusted CA certificates from the default file location

       -no-CApath
           Do not load the trusted CA certificates from the default directory location

       -md digest
           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).

       -cipher
           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 enc(1)
           for a list of ciphers supported by your version of OpenSSL.

           If not specified triple DES is used. Only used with -encrypt and -EncryptedData_create
           commands.

       -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.

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

       -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.

       -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.

       -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.

       -certfile file
           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 certificates should be in PEM format.

       -certsout file
           Any certificates contained in the message are written to file.

       -signer file
           A signing certificate when signing or resigning a message, this option can be used
           multiple times if more than one signer is required. If a message is being verified
           then the signers certificates will be written to this file if the verification was
           successful.

       -recip file
           When decrypting a message this specifies the recipients certificate. The certificate
           must match one of the recipients of the message or an error occurs.

           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.

       -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.

       -receipt_request_all, -receipt_request_first
           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_request_from emailaddress
           For -sign option include a signed receipt request. Add an explicit email address where
           receipts should be supplied.

       -receipt_request_to emailaddress
           Add an explicit email address where signed receipts should be sent to. This option
           must but supplied if a signed receipt it requested.

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

       -secretkey key
           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 id
           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.

       -econtent_type type
           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.

       -inkey file
           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.

       -keyopt name:opt
           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.

       -passin arg
           The private key password source. For more information about the format of arg see the
           PASS PHRASE ARGUMENTS section in openssl(1).

       -rand file...
           A file or files containing random data used to seed the random number generator.
           Multiple files can be specified separated by an OS-dependent character.  The separator
           is ; for MS-Windows, , for OpenVMS, and : for all others.

       [-writerand file]
           Writes random data to the specified file upon exit.  This can be used with a
           subsequent -rand flag.

       cert.pem...
           One or more certificates of message recipients: used when encrypting a message.

       -to, -from, -subject
           The relevant mail 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.

       -attime, -check_ss_sig, -crl_check, -crl_check_all, -explicit_policy, -extended_crl,
       -ignore_critical, -inhibit_any, -inhibit_map, -no_alt_chains, -no_check_time,
       -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
           Set various certificate chain validation options. See the verify(1) manual page for
           details.

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)).

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.

       The smime utility can only process the older PKCS#7 format. The cms utility 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 smime 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 mail:

        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 mail using RSA-PSS:

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

       Create encrypted mail 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

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.

HISTORY

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

       The keyopt option was first added in OpenSSL 1.0.2.

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

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

       The -no_alt_chains options was first added to OpenSSL 1.0.2b.

COPYRIGHT

       Copyright 2008-2018 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the OpenSSL license (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>.