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NSS Tools cmsutil

Using cmsutil


The cmsutil command-line utility uses the S/MIME Toolkit to perform basic operations, such as encryption and decryption, on Cryptographic Message Syntax (CMS) messages.


To run cmsutil, type the command

cmsutil option [arguments]

where option and arguments are combinations of the options and arguments listed in the following section. Each command takes one option. Each option may take zero or more arguments. To see a usage string, issue the command without options.

Options and Arguments

Options specify an action. Option arguments modify an action. The options and arguments for the cmsutil command are defined as follows:



Decode a message.


Encrypt a message.


Envelope a message.


Create a certificates-only message.


Sign a message.


-c content

Use this detached content (decode only).

-d dbdir

Specify the key/certificate database directory (default is ".")

-e envfile

Specify a file containing an enveloped message for a set of recipients to which you would like to send an encrypted message. If this is the first encrypted message for that set of recipients, a new enveloped message will be created that you can then use for future messages (encrypt only).


Include a signing time attribute (sign only).

-h num

Generate email headers with info about CMS message (decode only).

-i infile

Use infile as a source of data (default is stdin).

-N nickname

Specify nickname of certificate to sign with (sign only).


Suppress output of contents (decode only).

-o outfile

Use outfile as a destination of data (default is stdout).


Include an S/MIME capabilities attribute.

-p password

Use password as key database password.

-r recipient1,recipient2, . . . Specify list of recipients (email addresses) for an encrypted or enveloped message. For certificates-only message, list of certificates to send.
-T Suppress content in CMS message (sign only).
-u certusage Set type of cert usage (default is <tt>certUsageEmailSigner)</tt>.
<-Y ekprefnick Specify an encryption key preference by nickname.


cmsutil -C [-i infile] [-o outfile] [-d dbdir] [-p password] -r "recipient1,recipient2, . . ." -e envfile

cmsutil -D [-i infile] [-o outfile] [-d dbdir] [-p password] [-c content] [-n] [-h num]

cmsutil -E [-i infile] [-o outfile] [-d dbdir] [-p password] -r "recipient1,recipient2, . . ."

cmsutil -O [-i infile] [-o outfile] [-d dbdir] [-p password] -r "cert1,cert2, . . ."

cmsutil -S [-i infile] [-o outfile] [-d dbdir] [-p password] -N nickname[-TGP] [-Y ekprefnick]

Document Tags and Contributors

 Contributors to this page: Sheppy, kwilson
 Last updated by: Sheppy,