5 Author: Pekka Riikonen <priikone@silcnet.org>
7 Copyright (C) 2000 - 2001 Pekka Riikonen
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
22 #include "silcincludes.h"
24 /* Encodes Key Exchange Start Payload into a SILC Buffer to be sent
27 SilcSKEStatus silc_ske_payload_start_encode(SilcSKE ske,
28 SilcSKEStartPayload *payload,
29 SilcBuffer *return_buffer)
34 SILC_LOG_DEBUG(("Encoding KE Start Payload"));
37 return SILC_SKE_STATUS_ERROR;
39 buf = silc_buffer_alloc(payload->len);
40 silc_buffer_pull_tail(buf, SILC_BUFFER_END(buf));
42 /* Encode the payload */
43 ret = silc_buffer_format(buf,
44 SILC_STR_UI_CHAR(0), /* RESERVED field */
45 SILC_STR_UI_CHAR(payload->flags),
46 SILC_STR_UI_SHORT(payload->len),
47 SILC_STR_UI_XNSTRING(payload->cookie,
49 SILC_STR_UI_SHORT(payload->version_len),
50 SILC_STR_UI_XNSTRING(payload->version,
51 payload->version_len),
52 SILC_STR_UI_SHORT(payload->ke_grp_len),
53 SILC_STR_UI_XNSTRING(payload->ke_grp_list,
55 SILC_STR_UI_SHORT(payload->pkcs_alg_len),
56 SILC_STR_UI_XNSTRING(payload->pkcs_alg_list,
57 payload->pkcs_alg_len),
58 SILC_STR_UI_SHORT(payload->enc_alg_len),
59 SILC_STR_UI_XNSTRING(payload->enc_alg_list,
60 payload->enc_alg_len),
61 SILC_STR_UI_SHORT(payload->hash_alg_len),
62 SILC_STR_UI_XNSTRING(payload->hash_alg_list,
63 payload->hash_alg_len),
64 SILC_STR_UI_SHORT(payload->hmac_alg_len),
65 SILC_STR_UI_XNSTRING(payload->hmac_alg_list,
66 payload->hmac_alg_len),
67 SILC_STR_UI_SHORT(payload->comp_alg_len),
68 SILC_STR_UI_XNSTRING(payload->comp_alg_list,
69 payload->comp_alg_len),
72 silc_buffer_free(buf);
73 return SILC_SKE_STATUS_ERROR;
76 /* Return the encoded buffer */
79 SILC_LOG_HEXDUMP(("KE Start Payload"), buf->data, buf->len);
81 return SILC_SKE_STATUS_OK;
84 /* Parses the Key Exchange Start Payload. Parsed data is returned
85 to allocated payload structure. */
88 silc_ske_payload_start_decode(SilcSKE ske,
90 SilcSKEStartPayload **return_payload)
92 SilcSKEStartPayload *payload;
93 SilcSKEStatus status = SILC_SKE_STATUS_ERROR;
97 SILC_LOG_DEBUG(("Decoding Key Exchange Start Payload"));
99 SILC_LOG_HEXDUMP(("KE Start Payload"), buffer->data, buffer->len);
101 payload = silc_calloc(1, sizeof(*payload));
102 payload->cookie_len = SILC_SKE_COOKIE_LEN;
104 /* Parse start of the payload */
106 silc_buffer_unformat(buffer,
107 SILC_STR_UI_CHAR(&tmp), /* RESERVED Field */
108 SILC_STR_UI_CHAR(&payload->flags),
109 SILC_STR_UI_SHORT(&payload->len),
110 SILC_STR_UI_XNSTRING_ALLOC(&payload->cookie,
111 payload->cookie_len),
112 SILC_STR_UI16_NSTRING_ALLOC(&payload->version,
113 &payload->version_len),
114 SILC_STR_UI16_NSTRING_ALLOC(&payload->ke_grp_list,
115 &payload->ke_grp_len),
116 SILC_STR_UI16_NSTRING_ALLOC(&payload->pkcs_alg_list,
117 &payload->pkcs_alg_len),
118 SILC_STR_UI16_NSTRING_ALLOC(&payload->enc_alg_list,
119 &payload->enc_alg_len),
120 SILC_STR_UI16_NSTRING_ALLOC(&payload->hash_alg_list,
121 &payload->hash_alg_len),
122 SILC_STR_UI16_NSTRING_ALLOC(&payload->hmac_alg_list,
123 &payload->hmac_alg_len),
124 SILC_STR_UI16_NSTRING_ALLOC(&payload->comp_alg_list,
125 &payload->comp_alg_len),
128 status = SILC_SKE_STATUS_ERROR;
133 SILC_LOG_DEBUG(("Bad reserved field"));
134 status = SILC_SKE_STATUS_BAD_RESERVED_FIELD;
138 if (payload->len != buffer->len) {
139 SILC_LOG_DEBUG(("Bad payload length"));
140 status = SILC_SKE_STATUS_BAD_PAYLOAD_LENGTH;
144 /* Return the payload */
145 *return_payload = payload;
147 return SILC_SKE_STATUS_OK;
150 silc_ske_payload_start_free(payload);
152 ske->status = status;
156 /* Free's Start Payload */
158 void silc_ske_payload_start_free(SilcSKEStartPayload *payload)
162 silc_free(payload->cookie);
163 if (payload->version)
164 silc_free(payload->version);
165 if (payload->ke_grp_list)
166 silc_free(payload->ke_grp_list);
167 if (payload->pkcs_alg_list)
168 silc_free(payload->pkcs_alg_list);
169 if (payload->enc_alg_list)
170 silc_free(payload->enc_alg_list);
171 if (payload->hash_alg_list)
172 silc_free(payload->hash_alg_list);
173 if (payload->hmac_alg_list)
174 silc_free(payload->hmac_alg_list);
175 if (payload->comp_alg_list)
176 silc_free(payload->comp_alg_list);
181 /* Encodes Key Exchange Payload into a SILC Buffer to be sent to the other
184 SilcSKEStatus silc_ske_payload_ke_encode(SilcSKE ske,
185 SilcSKEKEPayload *payload,
186 SilcBuffer *return_buffer)
189 unsigned char *x_str;
193 SILC_LOG_DEBUG(("Encoding KE Payload"));
196 return SILC_SKE_STATUS_ERROR;
198 if (ske->start_payload &&
199 ske->start_payload->flags & SILC_SKE_SP_FLAG_MUTUAL &&
200 !payload->sign_data) {
201 SILC_LOG_DEBUG(("Signature data is missing"));
202 return SILC_SKE_STATUS_ERROR;
205 /* Encode the integer into binary data */
206 x_str = silc_mp_mp2bin(&payload->x, 0, &x_len);
208 /* Allocate channel payload buffer. The length of the buffer
209 is 4 + public key + 2 + x + 2 + signature. */
210 buf = silc_buffer_alloc(4 + payload->pk_len + 2 + x_len +
211 2 + payload->sign_len);
212 silc_buffer_pull_tail(buf, SILC_BUFFER_END(buf));
214 /* Encode the payload */
215 ret = silc_buffer_format(buf,
216 SILC_STR_UI_SHORT(payload->pk_len),
217 SILC_STR_UI_SHORT(payload->pk_type),
218 SILC_STR_UI_XNSTRING(payload->pk_data,
220 SILC_STR_UI_SHORT(x_len),
221 SILC_STR_UI_XNSTRING(x_str, x_len),
222 SILC_STR_UI_SHORT(payload->sign_len),
223 SILC_STR_UI_XNSTRING(payload->sign_data,
227 memset(x_str, 'F', x_len);
229 silc_buffer_free(buf);
230 return SILC_SKE_STATUS_ERROR;
233 /* Return encoded buffer */
234 *return_buffer = buf;
236 SILC_LOG_HEXDUMP(("KE Payload"), buf->data, buf->len);
238 memset(x_str, 'F', x_len);
241 return SILC_SKE_STATUS_OK;
244 /* Parses the Key Exchange Payload. Parsed data is returned to allocated
245 payload structure. */
247 SilcSKEStatus silc_ske_payload_ke_decode(SilcSKE ske,
249 SilcSKEKEPayload **return_payload)
251 SilcSKEStatus status = SILC_SKE_STATUS_ERROR;
252 SilcSKEKEPayload *payload;
253 unsigned char *x = NULL;
255 uint32 tot_len = 0, len2;
258 SILC_LOG_DEBUG(("Decoding Key Exchange Payload"));
260 SILC_LOG_HEXDUMP(("KE Payload"), buffer->data, buffer->len);
262 payload = silc_calloc(1, sizeof(*payload));
266 /* Parse start of the payload */
267 ret = silc_buffer_unformat(buffer,
268 SILC_STR_UI_SHORT(&payload->pk_len),
269 SILC_STR_UI_SHORT(&payload->pk_type),
272 status = SILC_SKE_STATUS_ERROR;
276 if (payload->pk_type == 0) {
277 status = SILC_SKE_STATUS_BAD_PAYLOAD;
281 tot_len += payload->pk_len + 4;
283 /* Parse PK data and the signature */
284 silc_buffer_pull(buffer, 4);
285 ret = silc_buffer_unformat(buffer,
286 SILC_STR_UI_XNSTRING_ALLOC(&payload->pk_data,
288 SILC_STR_UI16_NSTRING_ALLOC(&x, &x_len),
289 SILC_STR_UI16_NSTRING_ALLOC(&payload->sign_data,
293 status = SILC_SKE_STATUS_ERROR;
297 tot_len += x_len + 2;
298 tot_len += payload->sign_len + 2;
301 status = SILC_SKE_STATUS_BAD_PAYLOAD;
305 if (ske->start_payload &&
306 (ske->start_payload->flags & SILC_SKE_SP_FLAG_MUTUAL) &&
307 (payload->sign_len < 3 || !payload->sign_data)) {
308 SILC_LOG_DEBUG(("The signature data is missing - both parties are "
309 "required to do authentication"));
310 status = SILC_SKE_STATUS_BAD_PAYLOAD;
314 if (tot_len != len2) {
315 status = SILC_SKE_STATUS_BAD_PAYLOAD;
319 /* Decode the binary data to integer */
320 silc_mp_init(&payload->x);
321 silc_mp_bin2mp(x, x_len, &payload->x);
322 memset(x, 0, sizeof(x_len));
325 /* Return the payload */
326 *return_payload = payload;
328 return SILC_SKE_STATUS_OK;
331 if (payload->pk_data)
332 silc_free(payload->pk_data);
333 if (payload->sign_data)
334 silc_free(payload->sign_data);
338 ske->status = status;
342 /* Free's KE Payload */
344 void silc_ske_payload_ke_free(SilcSKEKEPayload *payload)
347 if (payload->pk_data)
348 silc_free(payload->pk_data);
349 silc_mp_uninit(&payload->x);
350 if (payload->sign_data)
351 silc_free(payload->sign_data);