zcert(3)

zcert(3)

CZMQ Manual - CZMQ/2.2.1

Name

zcert - work with CURVE security certificates

Synopsis

//  Create and initialize a new certificate in memory
CZMQ_EXPORT zcert_t *
    zcert_new (void);

//  Constructor, accepts public/secret key pair from caller
CZMQ_EXPORT zcert_t *
    zcert_new_from (byte *public_key, byte *secret_key);

//  Destroy a certificate in memory
CZMQ_EXPORT void
    zcert_destroy (zcert_t **self_p);

//  Return public part of key pair as 32-byte binary string
CZMQ_EXPORT byte *
    zcert_public_key (zcert_t *self);

//  Return secret part of key pair as 32-byte binary string
CZMQ_EXPORT byte *
    zcert_secret_key (zcert_t *self);

//  Return public part of key pair as Z85 armored string
CZMQ_EXPORT char *
    zcert_public_txt (zcert_t *self);

//  Return secret part of key pair as Z85 armored string
CZMQ_EXPORT char *
    zcert_secret_txt (zcert_t *self);

//  Set certificate metadata from formatted string.
CZMQ_EXPORT void
    zcert_set_meta (zcert_t *self, const char *name, const char *format, ...);

//  Get metadata value from certificate; if the metadata value doesn't
//  exist, returns NULL.
CZMQ_EXPORT char *
    zcert_meta (zcert_t *self, const char *name);

//  Get list of metadata fields from certificate. Caller is responsible for
//  destroying list. Caller should not modify the values of list items.
CZMQ_EXPORT zlist_t *
    zcert_meta_keys (zcert_t *self);

//  Load certificate from file (constructor)
CZMQ_EXPORT zcert_t *
    zcert_load (const char *filename);

//  Save full certificate (public + secret) to file for persistent storage
//  This creates one public file and one secret file (filename + "_secret").
CZMQ_EXPORT int
    zcert_save (zcert_t *self, const char *filename);

//  Save public certificate only to file for persistent storage
CZMQ_EXPORT int
    zcert_save_public (zcert_t *self, const char *filename);

//  Save secret certificate only to file for persistent storage
CZMQ_EXPORT int
    zcert_save_secret (zcert_t *self, const char *filename);

//  Apply certificate to socket, i.e. use for CURVE security on socket.
//  If certificate was loaded from public file, the secret key will be
//  undefined, and this certificate will not work successfully.
CZMQ_EXPORT void
    zcert_apply (zcert_t *self, void *zocket);

//  Return copy of certificate
CZMQ_EXPORT zcert_t *
    zcert_dup (zcert_t *self);

//  Return true if two certificates have the same keys
CZMQ_EXPORT bool
    zcert_eq (zcert_t *self, zcert_t *compare);

//  Print certificate contents to open stream
CZMQ_EXPORT void
    zcert_fprint (zcert_t *self, FILE *file);

//  Print certificate contents to stdout
CZMQ_EXPORT void
    zcert_print (zcert_t *self);

//  Self test of this class
CZMQ_EXPORT int
    zcert_test (bool verbose);

Description

The zcert class provides a way to create and work with security certificates for the ZMQ CURVE mechanism. A certificate contains a public + secret key pair, plus metadata. It can be used as a temporary object in memory, or persisted to disk. On disk, a certificate is stored as two files. One is public and contains only the public key. The second is secret and contains both keys. The two have the same filename, with the secret file adding "_secret". To exchange certificates, send the public file via some secure route. Certificates are not signed but are text files that can be verified by eye.

Certificates are stored in the ZPL (ZMQ RFC 4) format. They have two sections, "metadata" and "curve". The first contains a list of name = value pairs, one per line. Values may be enclosed in quotes. The curve section has a public-key = keyvalue and, for secret certificates, a secret-key = keyvalue line. The keyvalue is a Z85-encoded CURVE key.

Example

From zcert_test method

 // Create temporary directory for test files
# define TESTDIR ".test_zcert"
 zsys_dir_create (TESTDIR);

 // Create a simple certificate with metadata
 zcert_t *cert = zcert_new (); # if defined (HAVE_LIBSODIUM)

See also

czmq(7)

Authors

The CZMQ manual was written by Pieter Hintjens<moc.xitami|hp#moc.xitami|hp>.

Resources

Main web site: http://czmq.zeromq.org/

Report bugs to the ØMQ development mailing list: <gro.qmorez.stsil|ved-qmorez#gro.qmorez.stsil|ved-qmorez>

Copyright

Copyright (c) 1991-2014 iMatix and Contributors. License LGPLv3+: GNU LGPL 3 or later <http://gnu.org/licenses/lgpl.html>. This is free software: you are free to change it and redistribute it. There is NO WARRANTY, to the extent permitted by law. For details see the files COPYING and COPYING.LESSER included with the CZMQ distribution.