2 This file is part of GNUnet.
3 Copyright (C) 2014 GNUnet e.V.
5 GNUnet is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Affero General Public License as published
7 by the Free Software Foundation, either version 3 of the License,
8 or (at your option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Affero General Public License for more details.
15 You should have received a copy of the GNU Affero General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>.
18 SPDX-License-Identifier: AGPL3.0-or-later
21 #include "secretsharing.h"
24 * Read a share from its binary representation.
26 * @param data Binary representation of the share.
27 * @param len Length of @a data.
28 * @param[out] readlen Number of bytes read,
30 * @return The share, or NULL on error.
32 struct GNUNET_SECRETSHARING_Share *
33 GNUNET_SECRETSHARING_share_read (const void *data,
37 struct GNUNET_SECRETSHARING_Share *share;
38 const struct GNUNET_SECRETSHARING_ShareHeaderNBO *sh = data;
41 uint16_t payload_size;
43 payload_size = ntohs (sh->num_peers)
44 * (sizeof(uint16_t) + sizeof(struct
45 GNUNET_SECRETSHARING_FieldElement)
46 + sizeof(struct GNUNET_PeerIdentity));
49 *readlen = payload_size + sizeof *sh;
51 share = GNUNET_new (struct GNUNET_SECRETSHARING_Share);
53 share->threshold = ntohs (sh->threshold);
54 share->num_peers = ntohs (sh->num_peers);
55 share->my_peer = ntohs (sh->my_peer);
57 share->my_share = sh->my_share;
58 share->public_key = sh->public_key;
60 p = (const char *) &sh[1];
62 n = share->num_peers * sizeof(struct GNUNET_PeerIdentity);
63 share->peers = GNUNET_new_array (share->num_peers,
64 struct GNUNET_PeerIdentity);
65 GNUNET_memcpy (share->peers, p, n);
68 n = share->num_peers * sizeof(struct GNUNET_SECRETSHARING_FieldElement);
69 share->sigmas = GNUNET_new_array (share->num_peers,
70 struct GNUNET_SECRETSHARING_FieldElement);
71 GNUNET_memcpy (share->sigmas, p, n);
74 n = share->num_peers * sizeof(uint16_t);
75 share->original_indices = GNUNET_new_array (share->num_peers,
77 GNUNET_memcpy (share->original_indices, p, n);
84 * Convert a share to its binary representation.
85 * Can be called with a NULL @a buf to get the size of the share.
87 * @param share Share to write.
88 * @param buf Buffer to write to.
89 * @param buflen Number of writable bytes in @a buf.
90 * @param[out] writelen Pointer to store number of bytes written,
92 * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure.
95 GNUNET_SECRETSHARING_share_write (const struct
96 GNUNET_SECRETSHARING_Share *share,
97 void *buf, size_t buflen, size_t *writelen)
99 uint16_t payload_size;
100 struct GNUNET_SECRETSHARING_ShareHeaderNBO *sh;
104 payload_size = share->num_peers
105 * (sizeof(uint16_t) + sizeof(struct
106 GNUNET_SECRETSHARING_FieldElement)
107 + sizeof(struct GNUNET_PeerIdentity));
109 if (NULL != writelen)
110 *writelen = payload_size + sizeof(struct
111 GNUNET_SECRETSHARING_ShareHeaderNBO);
113 /* just a query for the writelen */
117 /* wrong buffer size */
118 if (buflen < payload_size + sizeof(struct
119 GNUNET_SECRETSHARING_ShareHeaderNBO))
120 return GNUNET_SYSERR;
124 sh->threshold = htons (share->threshold);
125 sh->num_peers = htons (share->num_peers);
126 sh->my_peer = htons (share->my_peer);
128 sh->my_share = share->my_share;
129 sh->public_key = share->public_key;
133 n = share->num_peers * sizeof(struct GNUNET_PeerIdentity);
134 GNUNET_memcpy (p, share->peers, n);
137 n = share->num_peers * sizeof(struct GNUNET_SECRETSHARING_FieldElement);
138 GNUNET_memcpy (p, share->sigmas, n);
141 n = share->num_peers * sizeof(uint16_t);
142 GNUNET_memcpy (p, share->original_indices, n);
149 GNUNET_SECRETSHARING_share_destroy (struct GNUNET_SECRETSHARING_Share *share)
151 GNUNET_free (share->original_indices);
152 share->original_indices = NULL;
153 GNUNET_free (share->sigmas);
154 share->sigmas = NULL;
155 GNUNET_free (share->peers);