2 * Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
11 #include "packet_locl.h"
13 #define DEFAULT_BUF_SIZE 256
15 int WPACKET_allocate_bytes(WPACKET *pkt, size_t len, unsigned char **allocbytes)
17 if (!WPACKET_reserve_bytes(pkt, len, allocbytes))
25 int WPACKET_sub_allocate_bytes__(WPACKET *pkt, size_t len,
26 unsigned char **allocbytes, size_t lenbytes)
28 if (!WPACKET_start_sub_packet_len__(pkt, lenbytes)
29 || !WPACKET_allocate_bytes(pkt, len, allocbytes)
30 || !WPACKET_close(pkt))
36 int WPACKET_reserve_bytes(WPACKET *pkt, size_t len, unsigned char **allocbytes)
38 /* Internal API, so should not fail */
39 assert(pkt->subs != NULL && len != 0);
40 if (pkt->subs == NULL || len == 0)
43 if (pkt->maxsize - pkt->written < len)
46 if (pkt->buf->length - pkt->written < len) {
50 reflen = (len > pkt->buf->length) ? len : pkt->buf->length;
52 if (reflen > SIZE_MAX / 2) {
56 if (newlen < DEFAULT_BUF_SIZE)
57 newlen = DEFAULT_BUF_SIZE;
59 if (BUF_MEM_grow(pkt->buf, newlen) == 0)
62 *allocbytes = (unsigned char *)pkt->buf->data + pkt->curr;
67 int WPACKET_sub_reserve_bytes__(WPACKET *pkt, size_t len,
68 unsigned char **allocbytes, size_t lenbytes)
70 if (!WPACKET_reserve_bytes(pkt, lenbytes + len, allocbytes))
73 *allocbytes += lenbytes;
78 static size_t maxmaxsize(size_t lenbytes)
80 if (lenbytes >= sizeof(size_t) || lenbytes == 0)
83 return ((size_t)1 << (lenbytes * 8)) - 1 + lenbytes;
86 int WPACKET_init_len(WPACKET *pkt, BUF_MEM *buf, size_t lenbytes)
88 unsigned char *lenchars;
90 /* Internal API, so should not fail */
98 pkt->maxsize = maxmaxsize(lenbytes);
100 pkt->subs = OPENSSL_zalloc(sizeof(*pkt->subs));
101 if (pkt->subs == NULL)
107 pkt->subs->pwritten = lenbytes;
108 pkt->subs->lenbytes = lenbytes;
110 if (!WPACKET_allocate_bytes(pkt, lenbytes, &lenchars)) {
111 OPENSSL_free(pkt->subs);
115 pkt->subs->packet_len = lenchars - (unsigned char *)pkt->buf->data;
120 int WPACKET_init(WPACKET *pkt, BUF_MEM *buf)
122 return WPACKET_init_len(pkt, buf, 0);
125 int WPACKET_set_flags(WPACKET *pkt, unsigned int flags)
127 /* Internal API, so should not fail */
128 assert(pkt->subs != NULL);
129 if (pkt->subs == NULL)
132 pkt->subs->flags = flags;
137 /* Store the |value| of length |len| at location |data| */
138 static int put_value(unsigned char *data, size_t value, size_t len)
140 for (data += len - 1; len > 0; len--) {
141 *data = (unsigned char)(value & 0xff);
146 /* Check whether we could fit the value in the assigned number of bytes */
155 * Internal helper function used by WPACKET_close() and WPACKET_finish() to
156 * close a sub-packet and write out its length if necessary.
158 static int wpacket_intern_close(WPACKET *pkt)
160 WPACKET_SUB *sub = pkt->subs;
161 size_t packlen = pkt->written - sub->pwritten;
164 && (sub->flags & WPACKET_FLAGS_NON_ZERO_LENGTH) != 0)
168 && sub->flags & WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH) {
169 /* Deallocate any bytes allocated for the length of the WPACKET */
170 if ((pkt->curr - sub->lenbytes) == sub->packet_len) {
171 pkt->written -= sub->lenbytes;
172 pkt->curr -= sub->lenbytes;
175 /* Don't write out the packet length */
180 /* Write out the WPACKET length if needed */
181 if (sub->lenbytes > 0
182 && !put_value((unsigned char *)&pkt->buf->data[sub->packet_len],
183 packlen, sub->lenbytes))
186 pkt->subs = sub->parent;
192 int WPACKET_close(WPACKET *pkt)
195 * Internal API, so should not fail - but we do negative testing of this
196 * so no assert (otherwise the tests fail)
198 if (pkt->subs == NULL || pkt->subs->parent == NULL)
201 return wpacket_intern_close(pkt);
204 int WPACKET_finish(WPACKET *pkt)
209 * Internal API, so should not fail - but we do negative testing of this
210 * so no assert (otherwise the tests fail)
212 if (pkt->subs == NULL || pkt->subs->parent != NULL)
215 ret = wpacket_intern_close(pkt);
217 OPENSSL_free(pkt->subs);
224 int WPACKET_start_sub_packet_len__(WPACKET *pkt, size_t lenbytes)
227 unsigned char *lenchars;
229 /* Internal API, so should not fail */
230 assert(pkt->subs != NULL);
231 if (pkt->subs == NULL)
234 sub = OPENSSL_zalloc(sizeof(*sub));
238 sub->parent = pkt->subs;
240 sub->pwritten = pkt->written + lenbytes;
241 sub->lenbytes = lenbytes;
248 if (!WPACKET_allocate_bytes(pkt, lenbytes, &lenchars))
250 /* Convert to an offset in case the underlying BUF_MEM gets realloc'd */
251 sub->packet_len = lenchars - (unsigned char *)pkt->buf->data;
256 int WPACKET_start_sub_packet(WPACKET *pkt)
258 return WPACKET_start_sub_packet_len__(pkt, 0);
261 int WPACKET_put_bytes__(WPACKET *pkt, unsigned int val, size_t size)
265 /* Internal API, so should not fail */
266 assert(size <= sizeof(unsigned int));
268 if (size > sizeof(unsigned int)
269 || !WPACKET_allocate_bytes(pkt, size, &data)
270 || !put_value(data, val, size))
276 int WPACKET_set_max_size(WPACKET *pkt, size_t maxsize)
281 /* Internal API, so should not fail */
282 assert(pkt->subs != NULL);
283 if (pkt->subs == NULL)
286 /* Find the WPACKET_SUB for the top level */
287 for (sub = pkt->subs; sub->parent != NULL; sub = sub->parent)
290 lenbytes = sub->lenbytes;
292 lenbytes = sizeof(pkt->maxsize);
294 if (maxmaxsize(lenbytes) < maxsize || maxsize < pkt->written)
297 pkt->maxsize = maxsize;
302 int WPACKET_memcpy(WPACKET *pkt, const void *src, size_t len)
309 if (!WPACKET_allocate_bytes(pkt, len, &dest))
312 memcpy(dest, src, len);
317 int WPACKET_sub_memcpy__(WPACKET *pkt, const void *src, size_t len,
320 if (!WPACKET_start_sub_packet_len__(pkt, lenbytes)
321 || !WPACKET_memcpy(pkt, src, len)
322 || !WPACKET_close(pkt))
328 int WPACKET_get_total_written(WPACKET *pkt, size_t *written)
330 /* Internal API, so should not fail */
331 assert(written != NULL);
335 *written = pkt->written;
340 int WPACKET_get_length(WPACKET *pkt, size_t *len)
342 /* Internal API, so should not fail */
343 assert(pkt->subs != NULL && len != NULL);
344 if (pkt->subs == NULL || len == NULL)
347 *len = pkt->written - pkt->subs->pwritten;
352 void WPACKET_cleanup(WPACKET *pkt)
354 WPACKET_SUB *sub, *parent;
356 for (sub = pkt->subs; sub != NULL; sub = parent) {
357 parent = sub->parent;