5 Author: Pekka Riikonen <priikone@poseidon.pspt.fi>
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"
23 #include "payload_internal.h"
25 /* Encodes Key Exchange Start Payload into a SILC Buffer to be sent
28 SilcSKEStatus silc_ske_payload_start_encode(SilcSKE ske,
29 SilcSKEStartPayload *payload,
30 SilcBuffer *return_buffer)
35 SILC_LOG_DEBUG(("Encoding KE Start Payload"));
38 return SILC_SKE_STATUS_ERROR;
40 buf = silc_buffer_alloc(payload->len);
41 silc_buffer_pull_tail(buf, SILC_BUFFER_END(buf));
43 /* Encode the payload */
44 ret = silc_buffer_format(buf,
45 SILC_STR_UI_CHAR(0), /* RESERVED field */
46 SILC_STR_UI_CHAR(payload->flags),
47 SILC_STR_UI_SHORT(payload->len),
48 SILC_STR_UI_XNSTRING(payload->cookie,
50 SILC_STR_UI_SHORT(payload->version_len),
51 SILC_STR_UI_XNSTRING(payload->version,
52 payload->version_len),
53 SILC_STR_UI_SHORT(payload->ke_grp_len),
54 SILC_STR_UI_XNSTRING(payload->ke_grp_list,
56 SILC_STR_UI_SHORT(payload->pkcs_alg_len),
57 SILC_STR_UI_XNSTRING(payload->pkcs_alg_list,
58 payload->pkcs_alg_len),
59 SILC_STR_UI_SHORT(payload->enc_alg_len),
60 SILC_STR_UI_XNSTRING(payload->enc_alg_list,
61 payload->enc_alg_len),
62 SILC_STR_UI_SHORT(payload->hash_alg_len),
63 SILC_STR_UI_XNSTRING(payload->hash_alg_list,
64 payload->hash_alg_len),
65 SILC_STR_UI_SHORT(payload->hmac_alg_len),
66 SILC_STR_UI_XNSTRING(payload->hmac_alg_list,
67 payload->hmac_alg_len),
68 SILC_STR_UI_SHORT(payload->comp_alg_len),
69 SILC_STR_UI_XNSTRING(payload->comp_alg_list,
70 payload->comp_alg_len),
73 silc_buffer_free(buf);
74 return SILC_SKE_STATUS_ERROR;
77 /* Return the encoded buffer */
80 SILC_LOG_HEXDUMP(("KE Start Payload"), buf->data, buf->len);
82 return SILC_SKE_STATUS_OK;
85 /* Parses the Key Exchange Start Payload. Parsed data is returned
86 to allocated payload structure. */
89 silc_ske_payload_start_decode(SilcSKE ske,
91 SilcSKEStartPayload **return_payload)
93 SilcSKEStartPayload *payload;
94 SilcSKEStatus status = SILC_SKE_STATUS_ERROR;
98 SILC_LOG_DEBUG(("Decoding Key Exchange Start Payload"));
100 SILC_LOG_HEXDUMP(("KE Start Payload"), buffer->data, buffer->len);
102 payload = silc_calloc(1, sizeof(*payload));
103 payload->cookie_len = SILC_SKE_COOKIE_LEN;
105 /* Parse start of the payload */
107 silc_buffer_unformat(buffer,
108 SILC_STR_UI_CHAR(&tmp), /* RESERVED Field */
109 SILC_STR_UI_CHAR(&payload->flags),
110 SILC_STR_UI_SHORT(&payload->len),
111 SILC_STR_UI_XNSTRING_ALLOC(&payload->cookie,
112 payload->cookie_len),
113 SILC_STR_UI16_NSTRING_ALLOC(&payload->version,
114 &payload->version_len),
115 SILC_STR_UI16_NSTRING_ALLOC(&payload->ke_grp_list,
116 &payload->ke_grp_len),
117 SILC_STR_UI16_NSTRING_ALLOC(&payload->pkcs_alg_list,
118 &payload->pkcs_alg_len),
119 SILC_STR_UI16_NSTRING_ALLOC(&payload->enc_alg_list,
120 &payload->enc_alg_len),
121 SILC_STR_UI16_NSTRING_ALLOC(&payload->hash_alg_list,
122 &payload->hash_alg_len),
123 SILC_STR_UI16_NSTRING_ALLOC(&payload->hmac_alg_list,
124 &payload->hmac_alg_len),
125 SILC_STR_UI16_NSTRING_ALLOC(&payload->comp_alg_list,
126 &payload->comp_alg_len),
129 status = SILC_SKE_STATUS_ERROR;
134 SILC_LOG_DEBUG(("Bad reserved field"));
135 status = SILC_SKE_STATUS_BAD_RESERVED_FIELD;
139 if (payload->len != buffer->len) {
140 SILC_LOG_DEBUG(("Bad payload length"));
141 status = SILC_SKE_STATUS_BAD_PAYLOAD_LENGTH;
145 /* Return the payload */
146 *return_payload = payload;
148 return SILC_SKE_STATUS_OK;
151 silc_ske_payload_start_free(payload);
153 ske->status = status;
157 /* Free's Start Payload */
159 void silc_ske_payload_start_free(SilcSKEStartPayload *payload)
163 silc_free(payload->cookie);
164 if (payload->version)
165 silc_free(payload->version);
166 if (payload->ke_grp_list)
167 silc_free(payload->ke_grp_list);
168 if (payload->pkcs_alg_list)
169 silc_free(payload->pkcs_alg_list);
170 if (payload->enc_alg_list)
171 silc_free(payload->enc_alg_list);
172 if (payload->hash_alg_list)
173 silc_free(payload->hash_alg_list);
174 if (payload->hmac_alg_list)
175 silc_free(payload->hmac_alg_list);
176 if (payload->comp_alg_list)
177 silc_free(payload->comp_alg_list);
182 /* Encodes Key Exchange Payload into a SILC Buffer to be sent to the other
185 SilcSKEStatus silc_ske_payload_ke_encode(SilcSKE ske,
186 SilcSKEKEPayload *payload,
187 SilcBuffer *return_buffer)
190 unsigned char *x_str;
194 SILC_LOG_DEBUG(("Encoding KE Payload"));
197 return SILC_SKE_STATUS_ERROR;
199 if (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;
254 unsigned short x_len;
255 unsigned int 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_len < 5) {
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->flags & SILC_SKE_SP_FLAG_MUTUAL) &&
306 (payload->sign_len < 3 || !payload->sign_data)) {
307 SILC_LOG_DEBUG(("The signature data is missing - both parties are "
308 "required to do authentication"));
309 status = SILC_SKE_STATUS_BAD_PAYLOAD;
313 if (tot_len != len2) {
314 status = SILC_SKE_STATUS_BAD_PAYLOAD;
318 /* Decode the binary data to integer */
319 silc_mp_init(&payload->x);
320 silc_mp_bin2mp(x, x_len, &payload->x);
321 memset(x, 0, sizeof(x_len));
324 /* Return the payload */
325 *return_payload = payload;
327 return SILC_SKE_STATUS_OK;
330 if (payload->pk_data)
331 silc_free(payload->pk_data);
332 if (payload->sign_data)
333 silc_free(payload->sign_data);
337 ske->status = status;
341 /* Free's KE Payload */
343 void silc_ske_payload_ke_free(SilcSKEKEPayload *payload)
346 if (payload->pk_data)
347 silc_free(payload->pk_data);
348 silc_mp_clear(&payload->x);
349 if (payload->sign_data)
350 silc_free(payload->sign_data);