openssl/ssl/packet_locl.h
Matt Caswell 9b36b7d9bd Add support for initialising WPACKETs from a static buffer
Normally WPACKETs will use a BUF_MEM which can grow as required. Sometimes
though that may be overkill for what is needed - a static buffer may be
sufficient. This adds that capability.

Reviewed-by: Rich Salz <rsalz@openssl.org>
2016-11-09 10:36:54 +00:00

865 lines
26 KiB
C

/*
* Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#ifndef HEADER_PACKET_LOCL_H
# define HEADER_PACKET_LOCL_H
# include <string.h>
# include <openssl/bn.h>
# include <openssl/buffer.h>
# include <openssl/crypto.h>
# include <openssl/e_os2.h>
# include "internal/numbers.h"
# ifdef __cplusplus
extern "C" {
# endif
typedef struct {
/* Pointer to where we are currently reading from */
const unsigned char *curr;
/* Number of bytes remaining */
size_t remaining;
} PACKET;
/* Internal unchecked shorthand; don't use outside this file. */
static ossl_inline void packet_forward(PACKET *pkt, size_t len)
{
pkt->curr += len;
pkt->remaining -= len;
}
/*
* Returns the number of bytes remaining to be read in the PACKET
*/
static ossl_inline size_t PACKET_remaining(const PACKET *pkt)
{
return pkt->remaining;
}
/*
* Returns a pointer to the first byte after the packet data.
* Useful for integrating with non-PACKET parsing code.
* Specifically, we use PACKET_end() to verify that a d2i_... call
* has consumed the entire packet contents.
*/
static ossl_inline const unsigned char *PACKET_end(const PACKET *pkt)
{
return pkt->curr + pkt->remaining;
}
/*
* Returns a pointer to the PACKET's current position.
* For use in non-PACKETized APIs.
*/
static ossl_inline const unsigned char *PACKET_data(const PACKET *pkt)
{
return pkt->curr;
}
/*
* Initialise a PACKET with |len| bytes held in |buf|. This does not make a
* copy of the data so |buf| must be present for the whole time that the PACKET
* is being used.
*/
__owur static ossl_inline int PACKET_buf_init(PACKET *pkt,
const unsigned char *buf,
size_t len)
{
/* Sanity check for negative values. */
if (len > (size_t)(SIZE_MAX / 2))
return 0;
pkt->curr = buf;
pkt->remaining = len;
return 1;
}
/* Initialize a PACKET to hold zero bytes. */
static ossl_inline void PACKET_null_init(PACKET *pkt)
{
pkt->curr = NULL;
pkt->remaining = 0;
}
/*
* Returns 1 if the packet has length |num| and its contents equal the |num|
* bytes read from |ptr|. Returns 0 otherwise (lengths or contents not equal).
* If lengths are equal, performs the comparison in constant time.
*/
__owur static ossl_inline int PACKET_equal(const PACKET *pkt, const void *ptr,
size_t num)
{
if (PACKET_remaining(pkt) != num)
return 0;
return CRYPTO_memcmp(pkt->curr, ptr, num) == 0;
}
/*
* Peek ahead and initialize |subpkt| with the next |len| bytes read from |pkt|.
* Data is not copied: the |subpkt| packet will share its underlying buffer with
* the original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
*/
__owur static ossl_inline int PACKET_peek_sub_packet(const PACKET *pkt,
PACKET *subpkt, size_t len)
{
if (PACKET_remaining(pkt) < len)
return 0;
return PACKET_buf_init(subpkt, pkt->curr, len);
}
/*
* Initialize |subpkt| with the next |len| bytes read from |pkt|. Data is not
* copied: the |subpkt| packet will share its underlying buffer with the
* original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
*/
__owur static ossl_inline int PACKET_get_sub_packet(PACKET *pkt,
PACKET *subpkt, size_t len)
{
if (!PACKET_peek_sub_packet(pkt, subpkt, len))
return 0;
packet_forward(pkt, len);
return 1;
}
/*
* Peek ahead at 2 bytes in network order from |pkt| and store the value in
* |*data|
*/
__owur static ossl_inline int PACKET_peek_net_2(const PACKET *pkt,
unsigned int *data)
{
if (PACKET_remaining(pkt) < 2)
return 0;
*data = ((unsigned int)(*pkt->curr)) << 8;
*data |= *(pkt->curr + 1);
return 1;
}
/* Equivalent of n2s */
/* Get 2 bytes in network order from |pkt| and store the value in |*data| */
__owur static ossl_inline int PACKET_get_net_2(PACKET *pkt, unsigned int *data)
{
if (!PACKET_peek_net_2(pkt, data))
return 0;
packet_forward(pkt, 2);
return 1;
}
/* Same as PACKET_get_net_2() but for a size_t */
__owur static ossl_inline int PACKET_get_net_2_len(PACKET *pkt, size_t *data)
{
unsigned int i;
int ret = PACKET_get_net_2(pkt, &i);
if (ret)
*data = (size_t)i;
return ret;
}
/*
* Peek ahead at 3 bytes in network order from |pkt| and store the value in
* |*data|
*/
__owur static ossl_inline int PACKET_peek_net_3(const PACKET *pkt,
unsigned long *data)
{
if (PACKET_remaining(pkt) < 3)
return 0;
*data = ((unsigned long)(*pkt->curr)) << 16;
*data |= ((unsigned long)(*(pkt->curr + 1))) << 8;
*data |= *(pkt->curr + 2);
return 1;
}
/* Equivalent of n2l3 */
/* Get 3 bytes in network order from |pkt| and store the value in |*data| */
__owur static ossl_inline int PACKET_get_net_3(PACKET *pkt, unsigned long *data)
{
if (!PACKET_peek_net_3(pkt, data))
return 0;
packet_forward(pkt, 3);
return 1;
}
/* Same as PACKET_get_net_3() but for a size_t */
__owur static ossl_inline int PACKET_get_net_3_len(PACKET *pkt, size_t *data)
{
unsigned long i;
int ret = PACKET_get_net_3(pkt, &i);
if (ret)
*data = (size_t)i;
return ret;
}
/*
* Peek ahead at 4 bytes in network order from |pkt| and store the value in
* |*data|
*/
__owur static ossl_inline int PACKET_peek_net_4(const PACKET *pkt,
unsigned long *data)
{
if (PACKET_remaining(pkt) < 4)
return 0;
*data = ((unsigned long)(*pkt->curr)) << 24;
*data |= ((unsigned long)(*(pkt->curr + 1))) << 16;
*data |= ((unsigned long)(*(pkt->curr + 2))) << 8;
*data |= *(pkt->curr + 3);
return 1;
}
/* Equivalent of n2l */
/* Get 4 bytes in network order from |pkt| and store the value in |*data| */
__owur static ossl_inline int PACKET_get_net_4(PACKET *pkt, unsigned long *data)
{
if (!PACKET_peek_net_4(pkt, data))
return 0;
packet_forward(pkt, 4);
return 1;
}
/* Same as PACKET_get_net_4() but for a size_t */
__owur static ossl_inline int PACKET_get_net_4_len(PACKET *pkt, size_t *data)
{
unsigned long i;
int ret = PACKET_get_net_4(pkt, &i);
if (ret)
*data = (size_t)i;
return ret;
}
/* Peek ahead at 1 byte from |pkt| and store the value in |*data| */
__owur static ossl_inline int PACKET_peek_1(const PACKET *pkt,
unsigned int *data)
{
if (!PACKET_remaining(pkt))
return 0;
*data = *pkt->curr;
return 1;
}
/* Get 1 byte from |pkt| and store the value in |*data| */
__owur static ossl_inline int PACKET_get_1(PACKET *pkt, unsigned int *data)
{
if (!PACKET_peek_1(pkt, data))
return 0;
packet_forward(pkt, 1);
return 1;
}
/* Same as PACKET_get_1() but for a size_t */
__owur static ossl_inline int PACKET_get_1_len(PACKET *pkt, size_t *data)
{
unsigned int i;
int ret = PACKET_get_1(pkt, &i);
if (ret)
*data = (size_t)i;
return ret;
}
/*
* Peek ahead at 4 bytes in reverse network order from |pkt| and store the value
* in |*data|
*/
__owur static ossl_inline int PACKET_peek_4(const PACKET *pkt,
unsigned long *data)
{
if (PACKET_remaining(pkt) < 4)
return 0;
*data = *pkt->curr;
*data |= ((unsigned long)(*(pkt->curr + 1))) << 8;
*data |= ((unsigned long)(*(pkt->curr + 2))) << 16;
*data |= ((unsigned long)(*(pkt->curr + 3))) << 24;
return 1;
}
/* Equivalent of c2l */
/*
* Get 4 bytes in reverse network order from |pkt| and store the value in
* |*data|
*/
__owur static ossl_inline int PACKET_get_4(PACKET *pkt, unsigned long *data)
{
if (!PACKET_peek_4(pkt, data))
return 0;
packet_forward(pkt, 4);
return 1;
}
/*
* Peek ahead at |len| bytes from the |pkt| and store a pointer to them in
* |*data|. This just points at the underlying buffer that |pkt| is using. The
* caller should not free this data directly (it will be freed when the
* underlying buffer gets freed
*/
__owur static ossl_inline int PACKET_peek_bytes(const PACKET *pkt,
const unsigned char **data,
size_t len)
{
if (PACKET_remaining(pkt) < len)
return 0;
*data = pkt->curr;
return 1;
}
/*
* Read |len| bytes from the |pkt| and store a pointer to them in |*data|. This
* just points at the underlying buffer that |pkt| is using. The caller should
* not free this data directly (it will be freed when the underlying buffer gets
* freed
*/
__owur static ossl_inline int PACKET_get_bytes(PACKET *pkt,
const unsigned char **data,
size_t len)
{
if (!PACKET_peek_bytes(pkt, data, len))
return 0;
packet_forward(pkt, len);
return 1;
}
/* Peek ahead at |len| bytes from |pkt| and copy them to |data| */
__owur static ossl_inline int PACKET_peek_copy_bytes(const PACKET *pkt,
unsigned char *data,
size_t len)
{
if (PACKET_remaining(pkt) < len)
return 0;
memcpy(data, pkt->curr, len);
return 1;
}
/*
* Read |len| bytes from |pkt| and copy them to |data|.
* The caller is responsible for ensuring that |data| can hold |len| bytes.
*/
__owur static ossl_inline int PACKET_copy_bytes(PACKET *pkt,
unsigned char *data, size_t len)
{
if (!PACKET_peek_copy_bytes(pkt, data, len))
return 0;
packet_forward(pkt, len);
return 1;
}
/*
* Copy packet data to |dest|, and set |len| to the number of copied bytes.
* If the packet has more than |dest_len| bytes, nothing is copied.
* Returns 1 if the packet data fits in |dest_len| bytes, 0 otherwise.
* Does not forward PACKET position (because it is typically the last thing
* done with a given PACKET).
*/
__owur static ossl_inline int PACKET_copy_all(const PACKET *pkt,
unsigned char *dest,
size_t dest_len, size_t *len)
{
if (PACKET_remaining(pkt) > dest_len) {
*len = 0;
return 0;
}
*len = pkt->remaining;
memcpy(dest, pkt->curr, pkt->remaining);
return 1;
}
/*
* Copy |pkt| bytes to a newly allocated buffer and store a pointer to the
* result in |*data|, and the length in |len|.
* If |*data| is not NULL, the old data is OPENSSL_free'd.
* If the packet is empty, or malloc fails, |*data| will be set to NULL.
* Returns 1 if the malloc succeeds and 0 otherwise.
* Does not forward PACKET position (because it is typically the last thing
* done with a given PACKET).
*/
__owur static ossl_inline int PACKET_memdup(const PACKET *pkt,
unsigned char **data, size_t *len)
{
size_t length;
OPENSSL_free(*data);
*data = NULL;
*len = 0;
length = PACKET_remaining(pkt);
if (length == 0)
return 1;
*data = OPENSSL_memdup(pkt->curr, length);
if (*data == NULL)
return 0;
*len = length;
return 1;
}
/*
* Read a C string from |pkt| and copy to a newly allocated, NUL-terminated
* buffer. Store a pointer to the result in |*data|.
* If |*data| is not NULL, the old data is OPENSSL_free'd.
* If the data in |pkt| does not contain a NUL-byte, the entire data is
* copied and NUL-terminated.
* Returns 1 if the malloc succeeds and 0 otherwise.
* Does not forward PACKET position (because it is typically the last thing done
* with a given PACKET).
*/
__owur static ossl_inline int PACKET_strndup(const PACKET *pkt, char **data)
{
OPENSSL_free(*data);
/* This will succeed on an empty packet, unless pkt->curr == NULL. */
*data = OPENSSL_strndup((const char *)pkt->curr, PACKET_remaining(pkt));
return (*data != NULL);
}
/* Returns 1 if |pkt| contains at least one 0-byte, 0 otherwise. */
static ossl_inline int PACKET_contains_zero_byte(const PACKET *pkt)
{
return memchr(pkt->curr, 0, pkt->remaining) != NULL;
}
/* Move the current reading position forward |len| bytes */
__owur static ossl_inline int PACKET_forward(PACKET *pkt, size_t len)
{
if (PACKET_remaining(pkt) < len)
return 0;
packet_forward(pkt, len);
return 1;
}
/*
* Reads a variable-length vector prefixed with a one-byte length, and stores
* the contents in |subpkt|. |pkt| can equal |subpkt|.
* Data is not copied: the |subpkt| packet will share its underlying buffer with
* the original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
* Upon failure, the original |pkt| and |subpkt| are not modified.
*/
__owur static ossl_inline int PACKET_get_length_prefixed_1(PACKET *pkt,
PACKET *subpkt)
{
unsigned int length;
const unsigned char *data;
PACKET tmp = *pkt;
if (!PACKET_get_1(&tmp, &length) ||
!PACKET_get_bytes(&tmp, &data, (size_t)length)) {
return 0;
}
*pkt = tmp;
subpkt->curr = data;
subpkt->remaining = length;
return 1;
}
/*
* Like PACKET_get_length_prefixed_1, but additionally, fails when there are
* leftover bytes in |pkt|.
*/
__owur static ossl_inline int PACKET_as_length_prefixed_1(PACKET *pkt,
PACKET *subpkt)
{
unsigned int length;
const unsigned char *data;
PACKET tmp = *pkt;
if (!PACKET_get_1(&tmp, &length) ||
!PACKET_get_bytes(&tmp, &data, (size_t)length) ||
PACKET_remaining(&tmp) != 0) {
return 0;
}
*pkt = tmp;
subpkt->curr = data;
subpkt->remaining = length;
return 1;
}
/*
* Reads a variable-length vector prefixed with a two-byte length, and stores
* the contents in |subpkt|. |pkt| can equal |subpkt|.
* Data is not copied: the |subpkt| packet will share its underlying buffer with
* the original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
* Upon failure, the original |pkt| and |subpkt| are not modified.
*/
__owur static ossl_inline int PACKET_get_length_prefixed_2(PACKET *pkt,
PACKET *subpkt)
{
unsigned int length;
const unsigned char *data;
PACKET tmp = *pkt;
if (!PACKET_get_net_2(&tmp, &length) ||
!PACKET_get_bytes(&tmp, &data, (size_t)length)) {
return 0;
}
*pkt = tmp;
subpkt->curr = data;
subpkt->remaining = length;
return 1;
}
/*
* Like PACKET_get_length_prefixed_2, but additionally, fails when there are
* leftover bytes in |pkt|.
*/
__owur static ossl_inline int PACKET_as_length_prefixed_2(PACKET *pkt,
PACKET *subpkt)
{
unsigned int length;
const unsigned char *data;
PACKET tmp = *pkt;
if (!PACKET_get_net_2(&tmp, &length) ||
!PACKET_get_bytes(&tmp, &data, (size_t)length) ||
PACKET_remaining(&tmp) != 0) {
return 0;
}
*pkt = tmp;
subpkt->curr = data;
subpkt->remaining = length;
return 1;
}
/*
* Reads a variable-length vector prefixed with a three-byte length, and stores
* the contents in |subpkt|. |pkt| can equal |subpkt|.
* Data is not copied: the |subpkt| packet will share its underlying buffer with
* the original |pkt|, so data wrapped by |pkt| must outlive the |subpkt|.
* Upon failure, the original |pkt| and |subpkt| are not modified.
*/
__owur static ossl_inline int PACKET_get_length_prefixed_3(PACKET *pkt,
PACKET *subpkt)
{
unsigned long length;
const unsigned char *data;
PACKET tmp = *pkt;
if (!PACKET_get_net_3(&tmp, &length) ||
!PACKET_get_bytes(&tmp, &data, (size_t)length)) {
return 0;
}
*pkt = tmp;
subpkt->curr = data;
subpkt->remaining = length;
return 1;
}
/* Writeable packets */
typedef struct wpacket_sub WPACKET_SUB;
struct wpacket_sub {
/* The parent WPACKET_SUB if we have one or NULL otherwise */
WPACKET_SUB *parent;
/*
* Offset into the buffer where the length of this WPACKET goes. We use an
* offset in case the buffer grows and gets reallocated.
*/
size_t packet_len;
/* Number of bytes in the packet_len or 0 if we don't write the length */
size_t lenbytes;
/* Number of bytes written to the buf prior to this packet starting */
size_t pwritten;
/* Flags for this sub-packet */
unsigned int flags;
};
typedef struct wpacket_st WPACKET;
struct wpacket_st {
/* The buffer where we store the output data */
BUF_MEM *buf;
/* Fixed sized buffer which can be used as an alternative to buf */
unsigned char *staticbuf;
/*
* Offset into the buffer where we are currently writing. We use an offset
* in case the buffer grows and gets reallocated.
*/
size_t curr;
/* Number of bytes written so far */
size_t written;
/* Maximum number of bytes we will allow to be written to this WPACKET */
size_t maxsize;
/* Our sub-packets (always at least one if not finished) */
WPACKET_SUB *subs;
};
/* Flags */
/* Default */
#define WPACKET_FLAGS_NONE 0
/* Error on WPACKET_close() if no data written to the WPACKET */
#define WPACKET_FLAGS_NON_ZERO_LENGTH 1
/*
* Abandon all changes on WPACKET_close() if no data written to the WPACKET,
* i.e. this does not write out a zero packet length
*/
#define WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH 2
/*
* Initialise a WPACKET with the buffer in |buf|. The buffer must exist
* for the whole time that the WPACKET is being used. Additionally |lenbytes| of
* data is preallocated at the start of the buffer to store the length of the
* WPACKET once we know it.
*/
int WPACKET_init_len(WPACKET *pkt, BUF_MEM *buf, size_t lenbytes);
/*
* Same as WPACKET_init_len except there is no preallocation of the WPACKET
* length.
*/
int WPACKET_init(WPACKET *pkt, BUF_MEM *buf);
/*
* Same as WPACKET_init_len except we do not use a growable BUF_MEM structure.
* A fixed buffer of memory |buf| of size |len| is used instead. A failure will
* occur if you attempt to write beyond the end of the buffer
*/
int WPACKET_init_static_len(WPACKET *pkt, unsigned char *buf, size_t len,
size_t lenbytes);
/*
* Set the flags to be applied to the current sub-packet
*/
int WPACKET_set_flags(WPACKET *pkt, unsigned int flags);
/*
* Closes the most recent sub-packet. It also writes out the length of the
* packet to the required location (normally the start of the WPACKET) if
* appropriate. The top level WPACKET should be closed using WPACKET_finish()
* instead of this function.
*/
int WPACKET_close(WPACKET *pkt);
/*
* The same as WPACKET_close() but only for the top most WPACKET. Additionally
* frees memory resources for this WPACKET.
*/
int WPACKET_finish(WPACKET *pkt);
/*
* Initialise a new sub-packet. Additionally |lenbytes| of data is preallocated
* at the start of the sub-packet to store its length once we know it. Don't
* call this directly. Use the convenience macros below instead.
*/
int WPACKET_start_sub_packet_len__(WPACKET *pkt, size_t lenbytes);
/*
* Convenience macros for calling WPACKET_start_sub_packet_len with different
* lengths
*/
#define WPACKET_start_sub_packet_u8(pkt) \
WPACKET_start_sub_packet_len__((pkt), 1)
#define WPACKET_start_sub_packet_u16(pkt) \
WPACKET_start_sub_packet_len__((pkt), 2)
#define WPACKET_start_sub_packet_u24(pkt) \
WPACKET_start_sub_packet_len__((pkt), 3)
#define WPACKET_start_sub_packet_u32(pkt) \
WPACKET_start_sub_packet_len__((pkt), 4)
/*
* Same as WPACKET_start_sub_packet_len__() except no bytes are pre-allocated
* for the sub-packet length.
*/
int WPACKET_start_sub_packet(WPACKET *pkt);
/*
* Allocate bytes in the WPACKET for the output. This reserves the bytes
* and counts them as "written", but doesn't actually do the writing. A pointer
* to the allocated bytes is stored in |*allocbytes|.
* WARNING: the allocated bytes must be filled in immediately, without further
* WPACKET_* calls. If not then the underlying buffer may be realloc'd and
* change its location.
*/
int WPACKET_allocate_bytes(WPACKET *pkt, size_t len,
unsigned char **allocbytes);
/*
* The same as WPACKET_allocate_bytes() except additionally a new sub-packet is
* started for the allocated bytes, and then closed immediately afterwards. The
* number of length bytes for the sub-packet is in |lenbytes|. Don't call this
* directly. Use the convenience macros below instead.
*/
int WPACKET_sub_allocate_bytes__(WPACKET *pkt, size_t len,
unsigned char **allocbytes, size_t lenbytes);
/*
* Convenience macros for calling WPACKET_sub_allocate_bytes with different
* lengths
*/
#define WPACKET_sub_allocate_bytes_u8(pkt, len, bytes) \
WPACKET_sub_allocate_bytes__((pkt), (len), (bytes), 1)
#define WPACKET_sub_allocate_bytes_u16(pkt, len, bytes) \
WPACKET_sub_allocate_bytes__((pkt), (len), (bytes), 2)
#define WPACKET_sub_allocate_bytes_u24(pkt, len, bytes) \
WPACKET_sub_allocate_bytes__((pkt), (len), (bytes), 3)
#define WPACKET_sub_allocate_bytes_u32(pkt, len, bytes) \
WPACKET_sub_allocate_bytes__((pkt), (len), (bytes), 4)
/*
* The same as WPACKET_allocate_bytes() except the reserved bytes are not
* actually counted as written. Typically this will be for when we don't know
* how big arbitrary data is going to be up front, but we do know what the
* maximum size will be. If this function is used, then it should be immediately
* followed by a WPACKET_allocate_bytes() call before any other WPACKET
* functions are called (unless the write to the allocated bytes is abandoned).
*
* For example: If we are generating a signature, then the size of that
* signature may not be known in advance. We can use WPACKET_reserve_bytes() to
* handle this:
*
* if (!WPACKET_sub_reserve_bytes_u16(&pkt, EVP_PKEY_size(pkey), &sigbytes1)
* || EVP_SignFinal(md_ctx, sigbytes1, &siglen, pkey) <= 0
* || !WPACKET_sub_allocate_bytes_u16(&pkt, siglen, &sigbytes2)
* || sigbytes1 != sigbytes2)
* goto err;
*/
int WPACKET_reserve_bytes(WPACKET *pkt, size_t len, unsigned char **allocbytes);
/*
* The "reserve_bytes" equivalent of WPACKET_sub_allocate_bytes__()
*/
int WPACKET_sub_reserve_bytes__(WPACKET *pkt, size_t len,
unsigned char **allocbytes, size_t lenbytes);
/*
* Convenience macros for WPACKET_sub_reserve_bytes with different lengths
*/
#define WPACKET_sub_reserve_bytes_u8(pkt, len, bytes) \
WPACKET_reserve_bytes__((pkt), (len), (bytes), 1)
#define WPACKET_sub_reserve_bytes_u16(pkt, len, bytes) \
WPACKET_sub_reserve_bytes__((pkt), (len), (bytes), 2)
#define WPACKET_sub_reserve_bytes_u24(pkt, len, bytes) \
WPACKET_sub_reserve_bytes__((pkt), (len), (bytes), 3)
#define WPACKET_sub_reserve_bytes_u32(pkt, len, bytes) \
WPACKET_sub_reserve_bytes__((pkt), (len), (bytes), 4)
/*
* Write the value stored in |val| into the WPACKET. The value will consume
* |bytes| amount of storage. An error will occur if |val| cannot be
* accommodated in |bytes| storage, e.g. attempting to write the value 256 into
* 1 byte will fail. Don't call this directly. Use the convenience macros below
* instead.
*/
int WPACKET_put_bytes__(WPACKET *pkt, unsigned int val, size_t bytes);
/*
* Convenience macros for calling WPACKET_put_bytes with different
* lengths
*/
#define WPACKET_put_bytes_u8(pkt, val) \
WPACKET_put_bytes__((pkt), (val), 1)
#define WPACKET_put_bytes_u16(pkt, val) \
WPACKET_put_bytes__((pkt), (val), 2)
#define WPACKET_put_bytes_u24(pkt, val) \
WPACKET_put_bytes__((pkt), (val), 3)
#define WPACKET_put_bytes_u32(pkt, val) \
WPACKET_put_bytes__((pkt), (val), 4)
/* Set a maximum size that we will not allow the WPACKET to grow beyond */
int WPACKET_set_max_size(WPACKET *pkt, size_t maxsize);
/* Copy |len| bytes of data from |*src| into the WPACKET. */
int WPACKET_memcpy(WPACKET *pkt, const void *src, size_t len);
/*
* Copy |len| bytes of data from |*src| into the WPACKET and prefix with its
* length (consuming |lenbytes| of data for the length). Don't call this
* directly. Use the convenience macros below instead.
*/
int WPACKET_sub_memcpy__(WPACKET *pkt, const void *src, size_t len,
size_t lenbytes);
/* Convenience macros for calling WPACKET_sub_memcpy with different lengths */
#define WPACKET_sub_memcpy_u8(pkt, src, len) \
WPACKET_sub_memcpy__((pkt), (src), (len), 1)
#define WPACKET_sub_memcpy_u16(pkt, src, len) \
WPACKET_sub_memcpy__((pkt), (src), (len), 2)
#define WPACKET_sub_memcpy_u24(pkt, src, len) \
WPACKET_sub_memcpy__((pkt), (src), (len), 3)
#define WPACKET_sub_memcpy_u32(pkt, src, len) \
WPACKET_sub_memcpy__((pkt), (src), (len), 4)
/*
* Return the total number of bytes written so far to the underlying buffer
* including any storage allocated for length bytes
*/
int WPACKET_get_total_written(WPACKET *pkt, size_t *written);
/*
* Returns the length of the current sub-packet. This excludes any bytes
* allocated for the length itself.
*/
int WPACKET_get_length(WPACKET *pkt, size_t *len);
/* Release resources in a WPACKET if a failure has occurred. */
void WPACKET_cleanup(WPACKET *pkt);
# ifdef __cplusplus
}
# endif
#endif /* HEADER_PACKET_LOCL_H */