Index: openssl/doc/apps/cms.pod |
=================================================================== |
--- openssl/doc/apps/cms.pod (revision 0) |
+++ openssl/doc/apps/cms.pod (revision 0) |
@@ -0,0 +1,602 @@ |
+=pod |
+ |
+=head1 NAME |
+ |
+cms - CMS utility |
+ |
+=head1 SYNOPSIS |
+ |
+B<openssl> B<cms> |
+[B<-encrypt>] |
+[B<-decrypt>] |
+[B<-sign>] |
+[B<-verify>] |
+[B<-cmsout>] |
+[B<-resign>] |
+[B<-data_create>] |
+[B<-data_out>] |
+[B<-digest_create>] |
+[B<-digest_verify>] |
+[B<-compress>] |
+[B<-uncompress>] |
+[B<-EncryptedData_encrypt>] |
+[B<-sign_receipt>] |
+[B<-verify_receipt receipt>] |
+[B<-in filename>] |
+[B<-inform SMIME|PEM|DER>] |
+[B<-rctform SMIME|PEM|DER>] |
+[B<-out filename>] |
+[B<-outform SMIME|PEM|DER>] |
+[B<-stream -indef -noindef>] |
+[B<-noindef>] |
+[B<-content filename>] |
+[B<-text>] |
+[B<-noout>] |
+[B<-print>] |
+[B<-CAfile file>] |
+[B<-CApath dir>] |
+[B<-md digest>] |
+[B<-[cipher]>] |
+[B<-nointern>] |
+[B<-no_signer_cert_verify>] |
+[B<-nocerts>] |
+[B<-noattr>] |
+[B<-nosmimecap>] |
+[B<-binary>] |
+[B<-nodetach>] |
+[B<-certfile file>] |
+[B<-certsout file>] |
+[B<-signer file>] |
+[B<-recip file>] |
+[B<-keyid>] |
+[B<-receipt_request_all -receipt_request_first>] |
+[B<-receipt_request_from emailaddress>] |
+[B<-receipt_request_to emailaddress>] |
+[B<-receipt_request_print>] |
+[B<-secretkey key>] |
+[B<-secretkeyid id>] |
+[B<-econtent_type type>] |
+[B<-inkey file>] |
+[B<-passin arg>] |
+[B<-rand file(s)>] |
+[B<cert.pem...>] |
+[B<-to addr>] |
+[B<-from addr>] |
+[B<-subject subj>] |
+[cert.pem]... |
+ |
+=head1 DESCRIPTION |
+ |
+The B<cms> command handles S/MIME v3.1 mail. It can encrypt, decrypt, sign and |
+verify, compress and uncompress S/MIME messages. |
+ |
+=head1 COMMAND 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. |
+ |
+=over 4 |
+ |
+=item B<-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>. |
+ |
+=item B<-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. |
+ |
+=item B<-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. |
+ |
+=item B<-verify> |
+ |
+verify signed mail. Expects a signed mail message on input and outputs |
+the signed data. Both clear text and opaque signing is supported. |
+ |
+=item B<-cmsout> |
+ |
+takes an input message and writes out a PEM encoded CMS structure. |
+ |
+=item B<-resign> |
+ |
+resign a message: take an existing message and one or more new signers. |
+ |
+=item B<-data_create> |
+ |
+Create a CMS B<Data> type. |
+ |
+=item B<-data_out> |
+ |
+B<Data> type and output the content. |
+ |
+=item B<-digest_create> |
+ |
+Create a CMS B<DigestedData> type. |
+ |
+=item B<-digest_verify> |
+ |
+Verify a CMS B<DigestedData> type and output the content. |
+ |
+=item B<-compress> |
+ |
+Create a CMS B<CompressedData> type. OpenSSL must be compiled with B<zlib> |
+support for this option to work, otherwise it will output an error. |
+ |
+=item B<-uncompress> |
+ |
+Uncompress a CMS B<CompressedData> type and output the content. OpenSSL must be |
+compiled with B<zlib> support for this option to work, otherwise it will |
+output an error. |
+ |
+=item B<-EncryptedData_encrypt> |
+ |
+Encrypt suppled content using supplied symmetric key and algorithm using a CMS |
+B<EncrytedData> type and output the content. |
+ |
+=item B<-sign_receipt> |
+ |
+Generate and output a signed receipt for the supplied message. The input |
+message B<must> contain a signed receipt request. Functionality is otherwise |
+similar to the B<-sign> operation. |
+ |
+=item B<-verify_receipt receipt> |
+ |
+Verify a signed receipt in filename B<receipt>. The input message B<must> |
+contain the original receipt request. Functionality is otherwise similar |
+to the B<-verify> operation. |
+ |
+=item B<-in filename> |
+ |
+the input message to be encrypted or signed or the message to be decrypted |
+or verified. |
+ |
+=item B<-inform SMIME|PEM|DER> |
+ |
+this specifies the input format for the CMS structure. The default |
+is B<SMIME> which reads an S/MIME format message. B<PEM> and B<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 |
+B<-encrypt> or B<-sign>) this option has no effect. |
+ |
+=item B<-rctform SMIME|PEM|DER> |
+ |
+specify the format for a signed receipt for use with the B<-receipt_verify> |
+operation. |
+ |
+=item B<-out filename> |
+ |
+the message text that has been decrypted or verified or the output MIME |
+format message that has been signed or verified. |
+ |
+=item B<-outform SMIME|PEM|DER> |
+ |
+this specifies the output format for the CMS structure. The default |
+is B<SMIME> which writes an S/MIME format message. B<PEM> and B<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 |
+B<-verify> or B<-decrypt>) this option has no effect. |
+ |
+=item B<-stream -indef -noindef> |
+ |
+the B<-stream> and B<-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 B<SMIME> it is currently off by default for all |
+other operations. |
+ |
+=item B<-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. |
+ |
+=item B<-content filename> |
+ |
+This specifies a file containing the detached content, this is only |
+useful with the B<-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. |
+ |
+=item B<-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. |
+ |
+=item B<-noout> |
+ |
+for the B<-cmsout> operation do not output the parsed CMS structure. This |
+is useful when combined with the B<-print> option or if the syntax of the CMS |
+structure is being checked. |
+ |
+=item B<-print> |
+ |
+for the B<-cmsout> operation print out all fields of the CMS structure. This |
+is mainly useful for testing purposes. |
+ |
+=item B<-CAfile file> |
+ |
+a file containing trusted CA certificates, only used with B<-verify>. |
+ |
+=item B<-CApath dir> |
+ |
+a directory containing trusted CA certificates, only used with |
+B<-verify>. This directory must be a standard certificate directory: that |
+is a hash of each subject name (using B<x509 -hash>) should be linked |
+to each certificate. |
+ |
+=item B<-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). |
+ |
+=item B<-[cipher]> |
+ |
+the encryption algorithm to use. For example triple DES (168 bits) - B<-des3> |
+or 256 bit AES - B<-aes256>. Any standard algorithm name (as used by the |
+EVP_get_cipherbyname() function) can also be used preceded by a dash, for |
+example B<-aes_128_cbc>. See L<B<enc>|enc(1)> for a list of ciphers |
+supported by your version of OpenSSL. |
+ |
+If not specified triple DES is used. Only used with B<-encrypt> and |
+B<-EncryptedData_create> commands. |
+ |
+=item B<-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 B<-certfile> option are used. |
+The supplied certificates can still be used as untrusted CAs however. |
+ |
+=item B<-no_signer_cert_verify> |
+ |
+do not verify the signers certificate of a signed message. |
+ |
+=item B<-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 B<-certfile> option for example). |
+ |
+=item B<-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. |
+ |
+=item B<-nosmimecap> |
+ |
+exclude the list of supported algorithms from signed attributes, other options |
+such as signing time and content type are still included. |
+ |
+=item B<-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. |
+ |
+=item B<-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. |
+ |
+=item B<-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. |
+ |
+=item B<-certsout file> |
+ |
+any certificates contained in the message are written to B<file>. |
+ |
+=item B<-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. |
+ |
+=item B<-recip file> |
+ |
+the recipients certificate when decrypting a message. This certificate |
+must match one of the recipients of the message or an error occurs. |
+ |
+=item B<-keyid> |
+ |
+use subject key identifier to identify certificates instead of issuer name and |
+serial number. The supplied certificate B<must> include a subject key |
+identifier extension. Supported by B<-sign> and B<-encrypt> options. |
+ |
+=item B<-receipt_request_all -receipt_request_first> |
+ |
+for B<-sign> option include a signed receipt request. Indicate requests should |
+be provided by all receipient or first tier recipients (those mailed directly |
+and not from a mailing list). Ignored it B<-receipt_request_from> is included. |
+ |
+=item B<-receipt_request_from emailaddress> |
+ |
+for B<-sign> option include a signed receipt request. Add an explicit email |
+address where receipts should be supplied. |
+ |
+=item B<-receipt_request_to emailaddress> |
+ |
+Add an explicit email address where signed receipts should be sent to. This |
+option B<must> but supplied if a signed receipt it requested. |
+ |
+=item B<-receipt_request_print> |
+ |
+For the B<-verify> operation print out the contents of any signed receipt |
+requests. |
+ |
+=item B<-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 B<-EncryptedData_encrypt> |
+B<-EncrryptedData_decrypt>, B<-encrypt> and B<-decrypt> options. When used |
+with B<-encrypt> or B<-decrypt> the supplied key is used to wrap or unwrap the |
+content encryption key using an AES key in the B<KEKRecipientInfo> type. |
+ |
+=item B<-secretkeyid id> |
+ |
+the key identifier for the supplied symmetric key for B<KEKRecipientInfo> type. |
+This option B<must> be present if the B<-secretkey> option is used with |
+B<-encrypt>. With B<-decrypt> operations the B<id> is used to locate the |
+relevant key if it is not supplied then an attempt is used to decrypt any |
+B<KEKRecipientInfo> structures. |
+ |
+=item B<-econtent_type type> |
+ |
+set the encapsulated content type to B<type> if not supplied the B<Data> type |
+is used. The B<type> argument can be any valid OID name in either text or |
+numerical format. |
+ |
+=item B<-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 B<-recip> or B<-signer> file. When signing this option can be used |
+multiple times to specify successive keys. |
+ |
+=item B<-passin arg> |
+ |
+the private key password source. For more information about the format of B<arg> |
+see the B<PASS PHRASE ARGUMENTS> section in L<openssl(1)|openssl(1)>. |
+ |
+=item B<-rand file(s)> |
+ |
+a file or files containing random data used to seed the random number |
+generator, or an EGD socket (see L<RAND_egd(3)|RAND_egd(3)>). |
+Multiple files can be specified separated by a OS-dependent character. |
+The separator is B<;> for MS-Windows, B<,> for OpenVMS, and B<:> for |
+all others. |
+ |
+=item B<cert.pem...> |
+ |
+one or more certificates of message recipients: used when encrypting |
+a message. |
+ |
+=item B<-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. |
+ |
+=item B<-purpose, -ignore_critical, -issuer_checks, -crl_check, -crl_check_all, -policy_check, -extended_crl, -x509_strict, -policy -check_ss_sig> |
+ |
+Set various certificate chain valiadition option. See the |
+L<B<verify>|verify(1)> manual page for details. |
+ |
+=back |
+ |
+=head1 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 wont display it |
+properly (if at all). You can use the B<-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 B<-encrypt> and B<-decrypt> reflect common usage in S/MIME |
+clients. Strictly speaking these process CMS enveloped data: CMS |
+encrypted data is used for other purposes. |
+ |
+The B<-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 B<-stream> and B<-indef> options enable experimental 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 B<-encrypt> operation and the |
+B<-sign> operation if the content is not detached. |
+ |
+Streaming is always used for the B<-sign> operation with detached data but |
+since the content is no longer part of the CMS structure the encoding |
+remains DER. |
+ |
+=head1 EXIT CODES |
+ |
+=over 4 |
+ |
+=item 0 |
+ |
+the operation was completely successfully. |
+ |
+=item 1 |
+ |
+an error occurred parsing the command options. |
+ |
+=item 2 |
+ |
+one of the input files could not be read. |
+ |
+=item 3 |
+ |
+an error occurred creating the CMS file or when reading the MIME |
+message. |
+ |
+=item 4 |
+ |
+an error occurred decrypting or verifying the message. |
+ |
+=item 5 |
+ |
+the message was verified correctly but an error occurred writing out |
+the signers certificates. |
+ |
+=back |
+ |
+=head1 COMPATIBILITY WITH PKCS#7 format. |
+ |
+The B<smime> utility can only process the older B<PKCS#7> format. The B<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 B<-keyid> option with B<-sign> or B<-encrypt>. |
+ |
+The B<-outform PEM> option uses different headers. |
+ |
+The B<-compress> option. |
+ |
+The B<-secretkey> option when used with B<-encrypt>. |
+ |
+Additionally the B<-EncryptedData_create> and B<-data_create> type cannot |
+be processed by the older B<smime> command. |
+ |
+=head1 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 B<-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 |
+ |
+=head1 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. |
+ |
+=head1 HISTORY |
+ |
+The use of multiple B<-signer> options and the B<-resign> command were first |
+added in OpenSSL 1.0.0 |
+ |
+ |
+=cut |