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);
41 return SILC_SKE_STATUS_OUT_OF_MEMORY;
42 silc_buffer_pull_tail(buf, SILC_BUFFER_END(buf));
44 /* Encode the payload */
45 ret = silc_buffer_format(buf,
46 SILC_STR_UI_CHAR(0), /* RESERVED field */
47 SILC_STR_UI_CHAR(payload->flags),
48 SILC_STR_UI_SHORT(payload->len),
49 SILC_STR_UI_XNSTRING(payload->cookie,
51 SILC_STR_UI_SHORT(payload->version_len),
52 SILC_STR_UI_XNSTRING(payload->version,
53 payload->version_len),
54 SILC_STR_UI_SHORT(payload->ke_grp_len),
55 SILC_STR_UI_XNSTRING(payload->ke_grp_list,
57 SILC_STR_UI_SHORT(payload->pkcs_alg_len),
58 SILC_STR_UI_XNSTRING(payload->pkcs_alg_list,
59 payload->pkcs_alg_len),
60 SILC_STR_UI_SHORT(payload->enc_alg_len),
61 SILC_STR_UI_XNSTRING(payload->enc_alg_list,
62 payload->enc_alg_len),
63 SILC_STR_UI_SHORT(payload->hash_alg_len),
64 SILC_STR_UI_XNSTRING(payload->hash_alg_list,
65 payload->hash_alg_len),
66 SILC_STR_UI_SHORT(payload->hmac_alg_len),
67 SILC_STR_UI_XNSTRING(payload->hmac_alg_list,
68 payload->hmac_alg_len),
69 SILC_STR_UI_SHORT(payload->comp_alg_len),
70 SILC_STR_UI_XNSTRING(payload->comp_alg_list,
71 payload->comp_alg_len),
74 silc_buffer_free(buf);
75 return SILC_SKE_STATUS_ERROR;
78 /* Return the encoded buffer */
81 SILC_LOG_HEXDUMP(("KE Start Payload"), buf->data, buf->len);
83 return SILC_SKE_STATUS_OK;
86 /* Parses the Key Exchange Start Payload. Parsed data is returned
87 to allocated payload structure. */
90 silc_ske_payload_start_decode(SilcSKE ske,
92 SilcSKEStartPayload **return_payload)
94 SilcSKEStartPayload *payload;
95 SilcSKEStatus status = SILC_SKE_STATUS_ERROR;
99 SILC_LOG_DEBUG(("Decoding Key Exchange Start Payload"));
101 SILC_LOG_HEXDUMP(("KE Start Payload"), buffer->data, buffer->len);
103 payload = silc_calloc(1, sizeof(*payload));
105 return SILC_SKE_STATUS_OUT_OF_MEMORY;
106 payload->cookie_len = SILC_SKE_COOKIE_LEN;
108 /* Parse start of the payload */
110 silc_buffer_unformat(buffer,
111 SILC_STR_UI_CHAR(&tmp), /* RESERVED Field */
112 SILC_STR_UI_CHAR(&payload->flags),
113 SILC_STR_UI_SHORT(&payload->len),
114 SILC_STR_UI_XNSTRING_ALLOC(&payload->cookie,
115 payload->cookie_len),
116 SILC_STR_UI16_NSTRING_ALLOC(&payload->version,
117 &payload->version_len),
118 SILC_STR_UI16_NSTRING_ALLOC(&payload->ke_grp_list,
119 &payload->ke_grp_len),
120 SILC_STR_UI16_NSTRING_ALLOC(&payload->pkcs_alg_list,
121 &payload->pkcs_alg_len),
122 SILC_STR_UI16_NSTRING_ALLOC(&payload->enc_alg_list,
123 &payload->enc_alg_len),
124 SILC_STR_UI16_NSTRING_ALLOC(&payload->hash_alg_list,
125 &payload->hash_alg_len),
126 SILC_STR_UI16_NSTRING_ALLOC(&payload->hmac_alg_list,
127 &payload->hmac_alg_len),
128 SILC_STR_UI16_NSTRING_ALLOC(&payload->comp_alg_list,
129 &payload->comp_alg_len),
132 SILC_LOG_ERROR(("Malformed KE Start Payload"));
133 status = SILC_SKE_STATUS_BAD_PAYLOAD;
138 SILC_LOG_DEBUG(("Bad reserved field"));
139 SILC_LOG_ERROR(("Bad RESERVED field in KE Start Payload"));
140 status = SILC_SKE_STATUS_BAD_RESERVED_FIELD;
144 if (payload->len != buffer->len) {
145 SILC_LOG_ERROR(("Garbage after KE Start Payload"));
146 status = SILC_SKE_STATUS_BAD_PAYLOAD_LENGTH;
150 /* Return the payload */
151 *return_payload = payload;
153 return SILC_SKE_STATUS_OK;
156 silc_ske_payload_start_free(payload);
158 ske->status = status;
162 /* Free's Start Payload */
164 void silc_ske_payload_start_free(SilcSKEStartPayload *payload)
167 silc_free(payload->cookie);
168 silc_free(payload->version);
169 silc_free(payload->ke_grp_list);
170 silc_free(payload->pkcs_alg_list);
171 silc_free(payload->enc_alg_list);
172 silc_free(payload->hash_alg_list);
173 silc_free(payload->hmac_alg_list);
174 silc_free(payload->comp_alg_list);
179 /* Encodes Key Exchange Payload into a SILC Buffer to be sent to the other
182 SilcSKEStatus silc_ske_payload_ke_encode(SilcSKE ske,
183 SilcSKEKEPayload *payload,
184 SilcBuffer *return_buffer)
187 unsigned char *x_str;
191 SILC_LOG_DEBUG(("Encoding KE Payload"));
194 return SILC_SKE_STATUS_ERROR;
196 if (ske->start_payload &&
197 ske->start_payload->flags & SILC_SKE_SP_FLAG_MUTUAL &&
198 !payload->sign_data) {
199 SILC_LOG_DEBUG(("Signature data is missing"));
200 return SILC_SKE_STATUS_ERROR;
203 /* Encode the integer into binary data */
204 x_str = silc_mp_mp2bin(&payload->x, 0, &x_len);
206 /* Allocate channel payload buffer. The length of the buffer
207 is 4 + public key + 2 + x + 2 + signature. */
208 buf = silc_buffer_alloc(4 + payload->pk_len + 2 + x_len +
209 2 + payload->sign_len);
211 return SILC_SKE_STATUS_OUT_OF_MEMORY;
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 SilcUInt32 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));
264 return SILC_SKE_STATUS_OUT_OF_MEMORY;
268 /* Parse start of the payload */
269 ret = silc_buffer_unformat(buffer,
270 SILC_STR_UI_SHORT(&payload->pk_len),
271 SILC_STR_UI_SHORT(&payload->pk_type),
274 SILC_LOG_ERROR(("Cannot decode public key from KE payload"));
275 status = SILC_SKE_STATUS_BAD_PAYLOAD;
279 if (ske->start_payload &&
280 (payload->pk_type < SILC_SKE_PK_TYPE_SILC ||
281 payload->pk_type > SILC_SKE_PK_TYPE_SPKI)) {
282 SILC_LOG_ERROR(("Malformed public key in KE payload"));
283 status = SILC_SKE_STATUS_BAD_PAYLOAD;
287 tot_len += payload->pk_len + 4;
289 /* Parse PK data and the signature */
290 silc_buffer_pull(buffer, 4);
291 ret = silc_buffer_unformat(buffer,
292 SILC_STR_UI_XNSTRING_ALLOC(&payload->pk_data,
294 SILC_STR_UI16_NSTRING_ALLOC(&x, &x_len),
295 SILC_STR_UI16_NSTRING_ALLOC(&payload->sign_data,
299 SILC_LOG_ERROR(("Malformed KE Payload"));
300 status = SILC_SKE_STATUS_BAD_PAYLOAD;
304 tot_len += x_len + 2;
305 tot_len += payload->sign_len + 2;
308 SILC_LOG_ERROR(("Too short signature in KE Payload"));
309 status = SILC_SKE_STATUS_BAD_PAYLOAD;
313 if (ske->start_payload &&
314 (ske->start_payload->flags & SILC_SKE_SP_FLAG_MUTUAL) &&
315 (payload->sign_len < 3 || !payload->sign_data)) {
316 SILC_LOG_ERROR(("The signature data is missing - both parties are "
317 "required to do authentication"));
318 status = SILC_SKE_STATUS_BAD_PAYLOAD;
322 if (tot_len != len2) {
323 SILC_LOG_ERROR(("Garbage after KE payload"));
324 status = SILC_SKE_STATUS_BAD_PAYLOAD_LENGTH;
328 /* Decode the binary data to integer */
329 silc_mp_init(&payload->x);
330 silc_mp_bin2mp(x, x_len, &payload->x);
331 memset(x, 0, sizeof(x_len));
334 /* Return the payload */
335 *return_payload = payload;
337 return SILC_SKE_STATUS_OK;
340 silc_free(payload->pk_data);
341 silc_free(payload->sign_data);
344 ske->status = status;
348 /* Free's KE Payload */
350 void silc_ske_payload_ke_free(SilcSKEKEPayload *payload)
353 silc_free(payload->pk_data);
354 silc_mp_uninit(&payload->x);
355 silc_free(payload->sign_data);