1ZCERT(3) CZMQ Manual ZCERT(3)
2
6 zcert - work with CURVE security certificates
7
9 // This is a stable class, and may not change except for emergencies. It
10 // is provided in stable builds.
11 // This class has draft methods, which may change over time. They are not
12 // in stable releases, by default. Use --enable-drafts to enable.
13 // Create and initialize a new certificate in memory
14 CZMQ_EXPORT zcert_t *
15 zcert_new (void);
16 // Accepts public/secret key pair from caller
18 CZMQ_EXPORT zcert_t *
19 zcert_new_from (const byte *public_key, const byte *secret_key);
20 // Load certificate from file
22 CZMQ_EXPORT zcert_t *
23 zcert_load (const char *filename);
24 // Destroy a certificate in memory
26 CZMQ_EXPORT void
27 zcert_destroy (zcert_t **self_p);
28 // Return public part of key pair as 32-byte binary string
30 CZMQ_EXPORT const byte *
31 zcert_public_key (zcert_t *self);
32 // Return secret part of key pair as 32-byte binary string
34 CZMQ_EXPORT const byte *
35 zcert_secret_key (zcert_t *self);
36 // Return public part of key pair as Z85 armored string
38 CZMQ_EXPORT const char *
39 zcert_public_txt (zcert_t *self);
40 // Return secret part of key pair as Z85 armored string
42 CZMQ_EXPORT const char *
43 zcert_secret_txt (zcert_t *self);
44 // Set certificate metadata from formatted string.
46 CZMQ_EXPORT void
47 zcert_set_meta (zcert_t *self, const char *name, const char *format, ...) CHECK_PRINTF (3);
48 // Get metadata value from certificate; if the metadata value doesn't
50 // exist, returns NULL.
51 CZMQ_EXPORT const char *
52 zcert_meta (zcert_t *self, const char *name);
53 // Get list of metadata fields from certificate. Caller is responsible for
55 // destroying list. Caller should not modify the values of list items.
56 CZMQ_EXPORT zlist_t *
57 zcert_meta_keys (zcert_t *self);
58 // Save full certificate (public + secret) to file for persistent storage
60 // This creates one public file and one secret file (filename + "_secret").
61 CZMQ_EXPORT int
62 zcert_save (zcert_t *self, const char *filename);
63 // Save public certificate only to file for persistent storage
65 CZMQ_EXPORT int
66 zcert_save_public (zcert_t *self, const char *filename);
67 // Save secret certificate only to file for persistent storage
69 CZMQ_EXPORT int
70 zcert_save_secret (zcert_t *self, const char *filename);
71 // Apply certificate to socket, i.e. use for CURVE security on socket.
73 // If certificate was loaded from public file, the secret key will be
74 // undefined, and this certificate will not work successfully.
75 CZMQ_EXPORT void
76 zcert_apply (zcert_t *self, void *socket);
77 // Return copy of certificate; if certificate is NULL or we exhausted
79 // heap memory, returns NULL.
80 // Caller owns return value and must destroy it when done.
81 CZMQ_EXPORT zcert_t *
82 zcert_dup (zcert_t *self);
83 // Return true if two certificates have the same keys
85 CZMQ_EXPORT bool
86 zcert_eq (zcert_t *self, zcert_t *compare);
87 // Print certificate contents to stdout
89 CZMQ_EXPORT void
90 zcert_print (zcert_t *self);
91 // Self test of this class
93 CZMQ_EXPORT void
94 zcert_test (bool verbose);
95 #ifdef CZMQ_BUILD_DRAFT_API
97 // *** Draft method, for development use, may change without warning ***
98 // Unset certificate metadata.
99 CZMQ_EXPORT void
100 zcert_unset_meta (zcert_t *self, const char *name);
101 #endif // CZMQ_BUILD_DRAFT_API
103 Please add '@interface' section in './../src/zcert.c'.
104
106 The zcert class provides a way to create and work with security
107 certificates for the ZMQ CURVE mechanism. A certificate contains a
108 public + secret key pair, plus metadata. It can be used as a temporary
109 object in memory, or persisted to disk. On disk, a certificate is
110 stored as two files. One is public and contains only the public key.
111 The second is secret and contains both keys. The two have the same
112 filename, with the secret file adding "_secret". To exchange
113 certificates, send the public file via some secure route. Certificates
114 are not signed but are text files that can be verified by eye.
115 Certificates are stored in the ZPL (ZMQ RFC 4) format. They have two
117 sections, "metadata" and "curve". The first contains a list of name =
118 value pairs, one per line. Values may be enclosed in quotes. The curve
119 section has a public-key = keyvalue and, for secret certificates, a
120 secret-key = keyvalue line. The keyvalue is a Z85-encoded CURVE key.
121
123 From zcert_test method.
124 // Create temporary directory for test files
126 # define TESTDIR ".test_zcert"
127 zsys_dir_create (TESTDIR);
128 // Create a simple certificate with metadata
130 zcert_t *cert = zcert_new ();
131 assert (cert);
132 zcert_set_meta (cert, "email", "ph@imatix.com");
133 zcert_set_meta (cert, "name", "Pieter Hintjens");
134 zcert_set_meta (cert, "organization", "iMatix Corporation");
135 zcert_set_meta (cert, "version", "%d", 1);
136 zcert_set_meta (cert, "delete_me", "now");
137 zcert_unset_meta (cert, "delete_me");
138 assert (streq (zcert_meta (cert, "email"), "ph@imatix.com"));
139 zlist_t *keys = zcert_meta_keys (cert);
140 assert (zlist_size (keys) == 4);
141 zlist_destroy (&keys);
142 // Check the dup and eq methods
144 zcert_t *shadow = zcert_dup (cert);
145 assert (zcert_eq (cert, shadow));
146 zcert_destroy (&shadow);
147 // Check we can save and load certificate
149 zcert_save (cert, TESTDIR "/mycert.txt");
150 assert (zsys_file_exists (TESTDIR "/mycert.txt"));
151 assert (zsys_file_exists (TESTDIR "/mycert.txt_secret"));
152 // Load certificate, will in fact load secret one
154 shadow = zcert_load (TESTDIR "/mycert.txt");
155 assert (shadow);
156 assert (zcert_eq (cert, shadow));
157 zcert_destroy (&shadow);
158 // Delete secret certificate, load public one
160 int rc = zsys_file_delete (TESTDIR "/mycert.txt_secret");
161 assert (rc == 0);
162 shadow = zcert_load (TESTDIR "/mycert.txt");
163 // 32-byte null key encodes as 40 '0' characters
165 assert (streq (zcert_secret_txt (shadow), FORTY_ZEROES));
166 zcert_destroy (&shadow);
168 zcert_destroy (&cert);
169 // Delete all test files
171 zdir_t *dir = zdir_new (TESTDIR, NULL);
172 assert (dir);
173 zdir_remove (dir, true);
174 zdir_destroy (&dir);
175
178 The czmq manual was written by the authors in the AUTHORS file.
179
181 Main web site:
182 Report bugs to the email <zeromq-dev@lists.zeromq.org[1]>
184
186 Copyright (c) the Contributors as noted in the AUTHORS file. This file
187 is part of CZMQ, the high-level C binding for 0MQ:
188 http://czmq.zeromq.org. This Source Code Form is subject to the terms
189 of the Mozilla Public License, v. 2.0. If a copy of the MPL was not
190 distributed with this file, You can obtain one at
191 http://mozilla.org/MPL/2.0/. LICENSE included with the czmq
192 distribution.
193
195 1. zeromq-dev@lists.zeromq.org
196 mailto:zeromq-dev@lists.zeromq.org
197CZMQ 4.0.2 12/31/2016 ZCERT(3)