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
10 #ifndef HEADER_PACKET_LOCL_H
11 # define HEADER_PACKET_LOCL_H
14 # include <openssl/bn.h>
15 # include <openssl/buffer.h>
16 # include <openssl/crypto.h>
17 # include <openssl/e_os2.h>
19 # include "internal/numbers.h"
26 /* Pointer to where we are currently reading from */
27 const unsigned char *curr;
28 /* Number of bytes remaining */
32 /* Internal unchecked shorthand; don't use outside this file. */
33 static ossl_inline void packet_forward(PACKET *pkt, size_t len)
36 pkt->remaining -= len;
40 * Returns the number of bytes remaining to be read in the PACKET
42 static ossl_inline size_t PACKET_remaining(const PACKET *pkt)
44 return pkt->remaining;
48 * Returns a pointer to the first byte after the packet data.
49 * Useful for integrating with non-PACKET parsing code.
50 * Specifically, we use PACKET_end() to verify that a d2i_... call
51 * has consumed the entire packet contents.
53 static ossl_inline const unsigned char *PACKET_end(const PACKET *pkt)
55 return pkt->curr + pkt->remaining;
59 * Returns a pointer to the PACKET's current position.
60 * For use in non-PACKETized APIs.
62 static ossl_inline const unsigned char *PACKET_data(const PACKET *pkt)
68 * Initialise a PACKET with |len| bytes held in |buf|. This does not make a
69 * copy of the data so |buf| must be present for the whole time that the PACKET
72 __owur static ossl_inline int PACKET_buf_init(PACKET *pkt,
73 const unsigned char *buf,
76 /* Sanity check for negative values. */
77 if (len > (size_t)(SIZE_MAX / 2))
85 /* Initialize a PACKET to hold zero bytes. */
86 static ossl_inline void PACKET_null_init(PACKET *pkt)
93 * Returns 1 if the packet has length |num| and its contents equal the |num|
94 * bytes read from |ptr|. Returns 0 otherwise (lengths or contents not equal).
95 * If lengths are equal, performs the comparison in constant time.
97 __owur static ossl_inline int PACKET_equal(const PACKET *pkt, const void *ptr,
100 if (PACKET_remaining(pkt) != num)
102 return CRYPTO_memcmp(pkt->curr, ptr, num) == 0;
106 * Peek ahead and initialize |subpkt| with the next |len| bytes read from |pkt|.
107 * Data is not copied: the |subpkt| packet will share its underlying buffer with
108 * the original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
110 __owur static ossl_inline int PACKET_peek_sub_packet(const PACKET *pkt,
111 PACKET *subpkt, size_t len)
113 if (PACKET_remaining(pkt) < len)
116 return PACKET_buf_init(subpkt, pkt->curr, len);
120 * Initialize |subpkt| with the next |len| bytes read from |pkt|. Data is not
121 * copied: the |subpkt| packet will share its underlying buffer with the
122 * original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
124 __owur static ossl_inline int PACKET_get_sub_packet(PACKET *pkt,
125 PACKET *subpkt, size_t len)
127 if (!PACKET_peek_sub_packet(pkt, subpkt, len))
130 packet_forward(pkt, len);
136 * Peek ahead at 2 bytes in network order from |pkt| and store the value in
139 __owur static ossl_inline int PACKET_peek_net_2(const PACKET *pkt,
142 if (PACKET_remaining(pkt) < 2)
145 *data = ((unsigned int)(*pkt->curr)) << 8;
146 *data |= *(pkt->curr + 1);
151 /* Equivalent of n2s */
152 /* Get 2 bytes in network order from |pkt| and store the value in |*data| */
153 __owur static ossl_inline int PACKET_get_net_2(PACKET *pkt, unsigned int *data)
155 if (!PACKET_peek_net_2(pkt, data))
158 packet_forward(pkt, 2);
163 /* Same as PACKET_get_net_2() but for a size_t */
164 __owur static ossl_inline int PACKET_get_net_2_len(PACKET *pkt, size_t *data)
169 ret = PACKET_get_net_2(pkt, &i);
177 * Peek ahead at 3 bytes in network order from |pkt| and store the value in
180 __owur static ossl_inline int PACKET_peek_net_3(const PACKET *pkt,
183 if (PACKET_remaining(pkt) < 3)
186 *data = ((unsigned long)(*pkt->curr)) << 16;
187 *data |= ((unsigned long)(*(pkt->curr + 1))) << 8;
188 *data |= *(pkt->curr + 2);
193 /* Equivalent of n2l3 */
194 /* Get 3 bytes in network order from |pkt| and store the value in |*data| */
195 __owur static ossl_inline int PACKET_get_net_3(PACKET *pkt, unsigned long *data)
197 if (!PACKET_peek_net_3(pkt, data))
200 packet_forward(pkt, 3);
205 /* Same as PACKET_get_net_3() but for a size_t */
206 __owur static ossl_inline int PACKET_get_net_3_len(PACKET *pkt, size_t *data)
211 ret = PACKET_get_net_3(pkt, &i);
219 * Peek ahead at 4 bytes in network order from |pkt| and store the value in
222 __owur static ossl_inline int PACKET_peek_net_4(const PACKET *pkt,
225 if (PACKET_remaining(pkt) < 4)
228 *data = ((unsigned long)(*pkt->curr)) << 24;
229 *data |= ((unsigned long)(*(pkt->curr + 1))) << 16;
230 *data |= ((unsigned long)(*(pkt->curr + 2))) << 8;
231 *data |= *(pkt->curr + 3);
236 /* Equivalent of n2l */
237 /* Get 4 bytes in network order from |pkt| and store the value in |*data| */
238 __owur static ossl_inline int PACKET_get_net_4(PACKET *pkt, unsigned long *data)
240 if (!PACKET_peek_net_4(pkt, data))
243 packet_forward(pkt, 4);
248 /* Same as PACKET_get_net_4() but for a size_t */
249 __owur static ossl_inline int PACKET_get_net_4_len(PACKET *pkt, size_t *data)
254 ret = PACKET_get_net_4(pkt, &i);
261 /* Peek ahead at 1 byte from |pkt| and store the value in |*data| */
262 __owur static ossl_inline int PACKET_peek_1(const PACKET *pkt,
265 if (!PACKET_remaining(pkt))
273 /* Get 1 byte from |pkt| and store the value in |*data| */
274 __owur static ossl_inline int PACKET_get_1(PACKET *pkt, unsigned int *data)
276 if (!PACKET_peek_1(pkt, data))
279 packet_forward(pkt, 1);
284 /* Same as PACKET_get_1() but for a size_t */
285 __owur static ossl_inline int PACKET_get_1_len(PACKET *pkt, size_t *data)
290 ret = PACKET_get_1(pkt, &i);
298 * Peek ahead at 4 bytes in reverse network order from |pkt| and store the value
301 __owur static ossl_inline int PACKET_peek_4(const PACKET *pkt,
304 if (PACKET_remaining(pkt) < 4)
308 *data |= ((unsigned long)(*(pkt->curr + 1))) << 8;
309 *data |= ((unsigned long)(*(pkt->curr + 2))) << 16;
310 *data |= ((unsigned long)(*(pkt->curr + 3))) << 24;
315 /* Equivalent of c2l */
317 * Get 4 bytes in reverse network order from |pkt| and store the value in
320 __owur static ossl_inline int PACKET_get_4(PACKET *pkt, unsigned long *data)
322 if (!PACKET_peek_4(pkt, data))
325 packet_forward(pkt, 4);
331 * Peek ahead at |len| bytes from the |pkt| and store a pointer to them in
332 * |*data|. This just points at the underlying buffer that |pkt| is using. The
333 * caller should not free this data directly (it will be freed when the
334 * underlying buffer gets freed
336 __owur static ossl_inline int PACKET_peek_bytes(const PACKET *pkt,
337 const unsigned char **data,
340 if (PACKET_remaining(pkt) < len)
349 * Read |len| bytes from the |pkt| and store a pointer to them in |*data|. This
350 * just points at the underlying buffer that |pkt| is using. The caller should
351 * not free this data directly (it will be freed when the underlying buffer gets
354 __owur static ossl_inline int PACKET_get_bytes(PACKET *pkt,
355 const unsigned char **data,
358 if (!PACKET_peek_bytes(pkt, data, len))
361 packet_forward(pkt, len);
366 /* Peek ahead at |len| bytes from |pkt| and copy them to |data| */
367 __owur static ossl_inline int PACKET_peek_copy_bytes(const PACKET *pkt,
371 if (PACKET_remaining(pkt) < len)
374 memcpy(data, pkt->curr, len);
380 * Read |len| bytes from |pkt| and copy them to |data|.
381 * The caller is responsible for ensuring that |data| can hold |len| bytes.
383 __owur static ossl_inline int PACKET_copy_bytes(PACKET *pkt,
384 unsigned char *data, size_t len)
386 if (!PACKET_peek_copy_bytes(pkt, data, len))
389 packet_forward(pkt, len);
395 * Copy packet data to |dest|, and set |len| to the number of copied bytes.
396 * If the packet has more than |dest_len| bytes, nothing is copied.
397 * Returns 1 if the packet data fits in |dest_len| bytes, 0 otherwise.
398 * Does not forward PACKET position (because it is typically the last thing
399 * done with a given PACKET).
401 __owur static ossl_inline int PACKET_copy_all(const PACKET *pkt,
403 size_t dest_len, size_t *len)
405 if (PACKET_remaining(pkt) > dest_len) {
409 *len = pkt->remaining;
410 memcpy(dest, pkt->curr, pkt->remaining);
415 * Copy |pkt| bytes to a newly allocated buffer and store a pointer to the
416 * result in |*data|, and the length in |len|.
417 * If |*data| is not NULL, the old data is OPENSSL_free'd.
418 * If the packet is empty, or malloc fails, |*data| will be set to NULL.
419 * Returns 1 if the malloc succeeds and 0 otherwise.
420 * Does not forward PACKET position (because it is typically the last thing
421 * done with a given PACKET).
423 __owur static ossl_inline int PACKET_memdup(const PACKET *pkt,
424 unsigned char **data, size_t *len)
432 length = PACKET_remaining(pkt);
437 *data = OPENSSL_memdup(pkt->curr, length);
446 * Read a C string from |pkt| and copy to a newly allocated, NUL-terminated
447 * buffer. Store a pointer to the result in |*data|.
448 * If |*data| is not NULL, the old data is OPENSSL_free'd.
449 * If the data in |pkt| does not contain a NUL-byte, the entire data is
450 * copied and NUL-terminated.
451 * Returns 1 if the malloc succeeds and 0 otherwise.
452 * Does not forward PACKET position (because it is typically the last thing done
453 * with a given PACKET).
455 __owur static ossl_inline int PACKET_strndup(const PACKET *pkt, char **data)
459 /* This will succeed on an empty packet, unless pkt->curr == NULL. */
460 *data = OPENSSL_strndup((const char *)pkt->curr, PACKET_remaining(pkt));
461 return (*data != NULL);
464 /* Returns 1 if |pkt| contains at least one 0-byte, 0 otherwise. */
465 static ossl_inline int PACKET_contains_zero_byte(const PACKET *pkt)
467 return memchr(pkt->curr, 0, pkt->remaining) != NULL;
470 /* Move the current reading position forward |len| bytes */
471 __owur static ossl_inline int PACKET_forward(PACKET *pkt, size_t len)
473 if (PACKET_remaining(pkt) < len)
476 packet_forward(pkt, len);
482 * Reads a variable-length vector prefixed with a one-byte length, and stores
483 * the contents in |subpkt|. |pkt| can equal |subpkt|.
484 * Data is not copied: the |subpkt| packet will share its underlying buffer with
485 * the original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
486 * Upon failure, the original |pkt| and |subpkt| are not modified.
488 __owur static ossl_inline int PACKET_get_length_prefixed_1(PACKET *pkt,
492 const unsigned char *data;
494 if (!PACKET_get_1(&tmp, &length) ||
495 !PACKET_get_bytes(&tmp, &data, (size_t)length)) {
501 subpkt->remaining = length;
507 * Like PACKET_get_length_prefixed_1, but additionally, fails when there are
508 * leftover bytes in |pkt|.
510 __owur static ossl_inline int PACKET_as_length_prefixed_1(PACKET *pkt,
514 const unsigned char *data;
516 if (!PACKET_get_1(&tmp, &length) ||
517 !PACKET_get_bytes(&tmp, &data, (size_t)length) ||
518 PACKET_remaining(&tmp) != 0) {
524 subpkt->remaining = length;
530 * Reads a variable-length vector prefixed with a two-byte length, and stores
531 * the contents in |subpkt|. |pkt| can equal |subpkt|.
532 * Data is not copied: the |subpkt| packet will share its underlying buffer with
533 * the original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
534 * Upon failure, the original |pkt| and |subpkt| are not modified.
536 __owur static ossl_inline int PACKET_get_length_prefixed_2(PACKET *pkt,
540 const unsigned char *data;
543 if (!PACKET_get_net_2(&tmp, &length) ||
544 !PACKET_get_bytes(&tmp, &data, (size_t)length)) {
550 subpkt->remaining = length;
556 * Like PACKET_get_length_prefixed_2, but additionally, fails when there are
557 * leftover bytes in |pkt|.
559 __owur static ossl_inline int PACKET_as_length_prefixed_2(PACKET *pkt,
563 const unsigned char *data;
566 if (!PACKET_get_net_2(&tmp, &length) ||
567 !PACKET_get_bytes(&tmp, &data, (size_t)length) ||
568 PACKET_remaining(&tmp) != 0) {
574 subpkt->remaining = length;
580 * Reads a variable-length vector prefixed with a three-byte length, and stores
581 * the contents in |subpkt|. |pkt| can equal |subpkt|.
582 * Data is not copied: the |subpkt| packet will share its underlying buffer with
583 * the original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
584 * Upon failure, the original |pkt| and |subpkt| are not modified.
586 __owur static ossl_inline int PACKET_get_length_prefixed_3(PACKET *pkt,
589 unsigned long length;
590 const unsigned char *data;
592 if (!PACKET_get_net_3(&tmp, &length) ||
593 !PACKET_get_bytes(&tmp, &data, (size_t)length)) {
599 subpkt->remaining = length;
604 /* Writeable packets */
606 typedef struct wpacket_sub WPACKET_SUB;
608 /* The parent WPACKET_SUB if we have one or NULL otherwise */
612 * Offset into the buffer where the length of this WPACKET goes. We use an
613 * offset in case the buffer grows and gets reallocated.
617 /* Number of bytes in the packet_len or 0 if we don't write the length */
620 /* Number of bytes written to the buf prior to this packet starting */
623 /* Flags for this sub-packet */
627 typedef struct wpacket_st WPACKET;
629 /* The buffer where we store the output data */
633 * Offset into the buffer where we are currently writing. We use an offset
634 * in case the buffer grows and gets reallocated.
638 /* Number of bytes written so far */
641 /* Maximum number of bytes we will allow to be written to this WPACKET */
644 /* Our sub-packets (always at least one if not finished) */
651 #define WPACKET_FLAGS_NONE 0
653 /* Error on WPACKET_close() if no data written to the WPACKET */
654 #define WPACKET_FLAGS_NON_ZERO_LENGTH 1
657 * Abandon all changes on WPACKET_close() if no data written to the WPACKET,
658 * i.e. this does not write out a zero packet length
660 #define WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH 2
664 * Initialise a WPACKET with the buffer in |buf|. The buffer must exist
665 * for the whole time that the WPACKET is being used. Additionally |lenbytes| of
666 * data is preallocated at the start of the buffer to store the length of the
667 * WPACKET once we know it.
669 int WPACKET_init_len(WPACKET *pkt, BUF_MEM *buf, size_t lenbytes);
672 * Same as WPACKET_init_len except there is no preallocation of the WPACKET
675 int WPACKET_init(WPACKET *pkt, BUF_MEM *buf);
678 * Set the flags to be applied to the current sub-packet
680 int WPACKET_set_flags(WPACKET *pkt, unsigned int flags);
683 * Closes the most recent sub-packet. It also writes out the length of the
684 * packet to the required location (normally the start of the WPACKET) if
685 * appropriate. The top level WPACKET should be closed using WPACKET_finish()
686 * instead of this function.
688 int WPACKET_close(WPACKET *pkt);
691 * The same as WPACKET_close() but only for the top most WPACKET. Additionally
692 * frees memory resources for this WPACKET.
694 int WPACKET_finish(WPACKET *pkt);
697 * Initialise a new sub-packet. Additionally |lenbytes| of data is preallocated
698 * at the start of the sub-packet to store its length once we know it. Don't
699 * call this directly. Use the convenience macros below instead.
701 int WPACKET_start_sub_packet_len__(WPACKET *pkt, size_t lenbytes);
704 * Convenience macros for calling WPACKET_start_sub_packet_len with different
707 #define WPACKET_start_sub_packet_u8(pkt) \
708 WPACKET_start_sub_packet_len__((pkt), 1)
709 #define WPACKET_start_sub_packet_u16(pkt) \
710 WPACKET_start_sub_packet_len__((pkt), 2)
711 #define WPACKET_start_sub_packet_u24(pkt) \
712 WPACKET_start_sub_packet_len__((pkt), 3)
713 #define WPACKET_start_sub_packet_u32(pkt) \
714 WPACKET_start_sub_packet_len__((pkt), 4)
717 * Same as WPACKET_start_sub_packet_len__() except no bytes are pre-allocated
718 * for the sub-packet length.
720 int WPACKET_start_sub_packet(WPACKET *pkt);
723 * Allocate bytes in the WPACKET for the output. This reserves the bytes
724 * and counts them as "written", but doesn't actually do the writing. A pointer
725 * to the allocated bytes is stored in |*allocbytes|.
726 * WARNING: the allocated bytes must be filled in immediately, without further
727 * WPACKET_* calls. If not then the underlying buffer may be realloc'd and
728 * change its location.
730 int WPACKET_allocate_bytes(WPACKET *pkt, size_t len,
731 unsigned char **allocbytes);
734 * The same as WPACKET_allocate_bytes() except additionally a new sub-packet is
735 * started for the allocated bytes, and then closed immediately afterwards. The
736 * number of length bytes for the sub-packet is in |lenbytes|. Don't call this
737 * directly. Use the convenience macros below instead.
739 int WPACKET_sub_allocate_bytes__(WPACKET *pkt, size_t len,
740 unsigned char **allocbytes, size_t lenbytes);
743 * Convenience macros for calling WPACKET_sub_allocate_bytes with different
746 #define WPACKET_sub_allocate_bytes_u8(pkt, len, bytes) \
747 WPACKET_sub_allocate_bytes__((pkt), (len), (bytes), 1)
748 #define WPACKET_sub_allocate_bytes_u16(pkt, len, bytes) \
749 WPACKET_sub_allocate_bytes__((pkt), (len), (bytes), 2)
750 #define WPACKET_sub_allocate_bytes_u24(pkt, len, bytes) \
751 WPACKET_sub_allocate_bytes__((pkt), (len), (bytes), 3)
752 #define WPACKET_sub_allocate_bytes_u32(pkt, len, bytes) \
753 WPACKET_sub_allocate_bytes__((pkt), (len), (bytes), 4)
756 * The same as WPACKET_allocate_bytes() except the reserved bytes are not
757 * actually counted as written. Typically this will be for when we don't know
758 * how big arbitrary data is going to be up front, but we do know what the
759 * maximum size will be. If this function is used, then it should be immediately
760 * followed by a WPACKET_allocate_bytes() call before any other WPACKET
761 * functions are called (unless the write to the allocated bytes is abandoned).
763 * For example: If we are generating a signature, then the size of that
764 * signature may not be known in advance. We can use WPACKET_reserve_bytes() to
767 * if (!WPACKET_sub_reserve_bytes_u16(&pkt, EVP_PKEY_size(pkey), &sigbytes1)
768 * || EVP_SignFinal(md_ctx, sigbytes1, &siglen, pkey) <= 0
769 * || !WPACKET_sub_allocate_bytes_u16(&pkt, siglen, &sigbytes2)
770 * || sigbytes1 != sigbytes2)
773 int WPACKET_reserve_bytes(WPACKET *pkt, size_t len, unsigned char **allocbytes);
776 * The "reserve_bytes" equivalent of WPACKET_sub_allocate_bytes__()
778 int WPACKET_sub_reserve_bytes__(WPACKET *pkt, size_t len,
779 unsigned char **allocbytes, size_t lenbytes);
782 * Convenience macros for WPACKET_sub_reserve_bytes with different lengths
784 #define WPACKET_sub_reserve_bytes_u8(pkt, len, bytes) \
785 WPACKET_reserve_bytes__((pkt), (len), (bytes), 1)
786 #define WPACKET_sub_reserve_bytes_u16(pkt, len, bytes) \
787 WPACKET_sub_reserve_bytes__((pkt), (len), (bytes), 2)
788 #define WPACKET_sub_reserve_bytes_u24(pkt, len, bytes) \
789 WPACKET_sub_reserve_bytes__((pkt), (len), (bytes), 3)
790 #define WPACKET_sub_reserve_bytes_u32(pkt, len, bytes) \
791 WPACKET_sub_reserve_bytes__((pkt), (len), (bytes), 4)
794 * Write the value stored in |val| into the WPACKET. The value will consume
795 * |bytes| amount of storage. An error will occur if |val| cannot be
796 * accommodated in |bytes| storage, e.g. attempting to write the value 256 into
797 * 1 byte will fail. Don't call this directly. Use the convenience macros below
800 int WPACKET_put_bytes__(WPACKET *pkt, unsigned int val, size_t bytes);
803 * Convenience macros for calling WPACKET_put_bytes with different
806 #define WPACKET_put_bytes_u8(pkt, val) \
807 WPACKET_put_bytes__((pkt), (val), 1)
808 #define WPACKET_put_bytes_u16(pkt, val) \
809 WPACKET_put_bytes__((pkt), (val), 2)
810 #define WPACKET_put_bytes_u24(pkt, val) \
811 WPACKET_put_bytes__((pkt), (val), 3)
812 #define WPACKET_put_bytes_u32(pkt, val) \
813 WPACKET_put_bytes__((pkt), (val), 4)
815 /* Set a maximum size that we will not allow the WPACKET to grow beyond */
816 int WPACKET_set_max_size(WPACKET *pkt, size_t maxsize);
818 /* Copy |len| bytes of data from |*src| into the WPACKET. */
819 int WPACKET_memcpy(WPACKET *pkt, const void *src, size_t len);
822 * Copy |len| bytes of data from |*src| into the WPACKET and prefix with its
823 * length (consuming |lenbytes| of data for the length). Don't call this
824 * directly. Use the convenience macros below instead.
826 int WPACKET_sub_memcpy__(WPACKET *pkt, const void *src, size_t len,
829 /* Convenience macros for calling WPACKET_sub_memcpy with different lengths */
830 #define WPACKET_sub_memcpy_u8(pkt, src, len) \
831 WPACKET_sub_memcpy__((pkt), (src), (len), 1)
832 #define WPACKET_sub_memcpy_u16(pkt, src, len) \
833 WPACKET_sub_memcpy__((pkt), (src), (len), 2)
834 #define WPACKET_sub_memcpy_u24(pkt, src, len) \
835 WPACKET_sub_memcpy__((pkt), (src), (len), 3)
836 #define WPACKET_sub_memcpy_u32(pkt, src, len) \
837 WPACKET_sub_memcpy__((pkt), (src), (len), 4)
840 * Return the total number of bytes written so far to the underlying buffer
841 * including any storage allocated for length bytes
843 int WPACKET_get_total_written(WPACKET *pkt, size_t *written);
846 * Returns the length of the current sub-packet. This excludes any bytes
847 * allocated for the length itself.
849 int WPACKET_get_length(WPACKET *pkt, size_t *len);
851 /* Release resources in a WPACKET if a failure has occurred. */
852 void WPACKET_cleanup(WPACKET *pkt);
858 #endif /* HEADER_PACKET_LOCL_H */