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Diffstat (limited to 'thirdparty/internal/packet.h')
-rw-r--r-- | thirdparty/internal/packet.h | 902 |
1 files changed, 902 insertions, 0 deletions
diff --git a/thirdparty/internal/packet.h b/thirdparty/internal/packet.h new file mode 100644 index 00000000..170997db --- /dev/null +++ b/thirdparty/internal/packet.h @@ -0,0 +1,902 @@ +/* + * Copyright 2015-2021 The OpenSSL Project Authors. All Rights Reserved. + * + * Licensed under the Apache License 2.0 (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 OSSL_INTERNAL_PACKET_H +# define OSSL_INTERNAL_PACKET_H +# pragma once + +# include <string.h> +# include <openssl/bn.h> +# include <openssl/buffer.h> +# include <openssl/crypto.h> +# include <openssl/e_os2.h> + +# include "internal/numbers.h" + +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; + + /* Writing from the end first? */ + unsigned int endfirst : 1; +}; + +/* 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 there is no underlying buffer. No data is + * ever actually written. We just keep track of how much data would have been + * written if a buffer was there. + */ +int WPACKET_init_null(WPACKET *pkt, size_t lenbytes); + +/* + * Same as WPACKET_init_null except we set the WPACKET to assume DER length + * encoding for sub-packets. + */ +int WPACKET_init_null_der(WPACKET *pkt); + +/* + * 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); + +/* + * Same as WPACKET_init_static_len except lenbytes is always 0, and we set the + * WPACKET to write to the end of the buffer moving towards the start and use + * DER length encoding for sub-packets. + */ +int WPACKET_init_der(WPACKET *pkt, unsigned char *buf, size_t len); + +/* + * 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); + +/* + * Iterate through all the sub-packets and write out their lengths as if they + * were being closed. The lengths will be overwritten with the final lengths + * when the sub-packets are eventually closed (which may be different if more + * data is added to the WPACKET). This function fails if a sub-packet is of 0 + * length and WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH is set. + */ +int WPACKET_fill_lengths(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|. |allocbytes| may be NULL. + * 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_get_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); + +/* Set |len| bytes of data to |ch| into the WPACKET. */ +int WPACKET_memset(WPACKET *pkt, int ch, 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); + +/* + * Returns a pointer to the current write location, but does not allocate any + * bytes. + */ +unsigned char *WPACKET_get_curr(WPACKET *pkt); + +/* Returns true if the underlying buffer is actually NULL */ +int WPACKET_is_null_buf(WPACKET *pkt); + +/* Release resources in a WPACKET if a failure has occurred. */ +void WPACKET_cleanup(WPACKET *pkt); + +#endif /* OSSL_INTERNAL_PACKET_H */ |