pineapple-src/externals/libressl/crypto/bytestring/bytestring.h
2022-04-24 22:29:35 +02:00

566 lines
19 KiB
C
Executable file

/* $OpenBSD: bytestring.h,v 1.3 2022/01/06 14:32:55 jsing Exp $ */
/*
* Copyright (c) 2014, Google Inc.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef OPENSSL_HEADER_BYTESTRING_H
#define OPENSSL_HEADER_BYTESTRING_H
#include <sys/types.h>
#include <stdint.h>
__BEGIN_HIDDEN_DECLS
/*
* Bytestrings are used for parsing and building TLS and ASN.1 messages.
*
* A "CBS" (CRYPTO ByteString) represents a string of bytes in memory and
* provides utility functions for safely parsing length-prefixed structures
* like TLS and ASN.1 from it.
*
* A "CBB" (CRYPTO ByteBuilder) is a memory buffer that grows as needed and
* provides utility functions for building length-prefixed messages.
*/
/* CRYPTO ByteString */
typedef struct cbs_st {
const uint8_t *data;
size_t initial_len;
size_t len;
} CBS;
/*
* CBS_init sets |cbs| to point to |data|. It does not take ownership of
* |data|.
*/
void CBS_init(CBS *cbs, const uint8_t *data, size_t len);
/*
* CBS_skip advances |cbs| by |len| bytes. It returns one on success and zero
* otherwise.
*/
int CBS_skip(CBS *cbs, size_t len);
/*
* CBS_data returns a pointer to the contents of |cbs|.
*/
const uint8_t *CBS_data(const CBS *cbs);
/*
* CBS_len returns the number of bytes remaining in |cbs|.
*/
size_t CBS_len(const CBS *cbs);
/*
* CBS_offset returns the current offset into the original data of |cbs|.
*/
size_t CBS_offset(const CBS *cbs);
/*
* CBS_stow copies the current contents of |cbs| into |*out_ptr| and
* |*out_len|. If |*out_ptr| is not NULL, the contents are freed with
* free. It returns one on success and zero on allocation failure. On
* success, |*out_ptr| should be freed with free. If |cbs| is empty,
* |*out_ptr| will be NULL.
*/
int CBS_stow(const CBS *cbs, uint8_t **out_ptr, size_t *out_len);
/*
* CBS_strdup copies the current contents of |cbs| into |*out_ptr| as a
* NUL-terminated C string. If |*out_ptr| is not NULL, the contents are freed
* with free. It returns one on success and zero on allocation
* failure. On success, |*out_ptr| should be freed with free.
*
* NOTE: If |cbs| contains NUL bytes, the string will be truncated. Call
* |CBS_contains_zero_byte(cbs)| to check for NUL bytes.
*/
int CBS_strdup(const CBS *cbs, char **out_ptr);
/*
* CBS_write_bytes writes all of the remaining data from |cbs| into |dst|
* if it is at most |dst_len| bytes. If |copied| is not NULL, it will be set
* to the amount copied. It returns one on success and zero otherwise.
*/
int CBS_write_bytes(const CBS *cbs, uint8_t *dst, size_t dst_len,
size_t *copied);
/*
* CBS_contains_zero_byte returns one if the current contents of |cbs| contains
* a NUL byte and zero otherwise.
*/
int CBS_contains_zero_byte(const CBS *cbs);
/*
* CBS_mem_equal compares the current contents of |cbs| with the |len| bytes
* starting at |data|. If they're equal, it returns one, otherwise zero. If the
* lengths match, it uses a constant-time comparison.
*/
int CBS_mem_equal(const CBS *cbs, const uint8_t *data, size_t len);
/*
* CBS_get_u8 sets |*out| to the next uint8_t from |cbs| and advances |cbs|. It
* returns one on success and zero on error.
*/
int CBS_get_u8(CBS *cbs, uint8_t *out);
/*
* CBS_get_u16 sets |*out| to the next, big-endian uint16_t from |cbs| and
* advances |cbs|. It returns one on success and zero on error.
*/
int CBS_get_u16(CBS *cbs, uint16_t *out);
/*
* CBS_get_u24 sets |*out| to the next, big-endian 24-bit value from |cbs| and
* advances |cbs|. It returns one on success and zero on error.
*/
int CBS_get_u24(CBS *cbs, uint32_t *out);
/*
* CBS_get_u32 sets |*out| to the next, big-endian uint32_t value from |cbs|
* and advances |cbs|. It returns one on success and zero on error.
*/
int CBS_get_u32(CBS *cbs, uint32_t *out);
/*
* CBS_get_u64 sets |*out| to the next, big-endian uint64_t value from |cbs|
* and advances |cbs|. It returns one on success and zero on error.
*/
int CBS_get_u64(CBS *cbs, uint64_t *out);
/*
* CBS_get_last_u8 sets |*out| to the last uint8_t from |cbs| and shortens
* |cbs|. It returns one on success and zero on error.
*/
int CBS_get_last_u8(CBS *cbs, uint8_t *out);
/*
* CBS_get_bytes sets |*out| to the next |len| bytes from |cbs| and advances
* |cbs|. It returns one on success and zero on error.
*/
int CBS_get_bytes(CBS *cbs, CBS *out, size_t len);
/*
* CBS_get_u8_length_prefixed sets |*out| to the contents of an 8-bit,
* length-prefixed value from |cbs| and advances |cbs| over it. It returns one
* on success and zero on error.
*/
int CBS_get_u8_length_prefixed(CBS *cbs, CBS *out);
/*
* CBS_get_u16_length_prefixed sets |*out| to the contents of a 16-bit,
* big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It
* returns one on success and zero on error.
*/
int CBS_get_u16_length_prefixed(CBS *cbs, CBS *out);
/*
* CBS_get_u24_length_prefixed sets |*out| to the contents of a 24-bit,
* big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It
* returns one on success and zero on error.
*/
int CBS_get_u24_length_prefixed(CBS *cbs, CBS *out);
/*
* CBS_peek_u8 sets |*out| to the next uint8_t from |cbs|, but does not advance
* |cbs|. It returns one on success and zero on error.
*/
int CBS_peek_u8(CBS *cbs, uint8_t *out);
/*
* CBS_peek_u16 sets |*out| to the next, big-endian uint16_t from |cbs|, but
* does not advance |cbs|. It returns one on success and zero on error.
*/
int CBS_peek_u16(CBS *cbs, uint16_t *out);
/*
* CBS_peek_u24 sets |*out| to the next, big-endian 24-bit value from |cbs|, but
* does not advance |cbs|. It returns one on success and zero on error.
*/
int CBS_peek_u24(CBS *cbs, uint32_t *out);
/*
* CBS_peek_u32 sets |*out| to the next, big-endian uint32_t value from |cbs|,
* but does not advance |cbs|. It returns one on success and zero on error.
*/
int CBS_peek_u32(CBS *cbs, uint32_t *out);
/*
* CBS_peek_last_u8 sets |*out| to the last uint8_t from |cbs|, but does not
* shorten |cbs|. It returns one on success and zero on error.
*/
int CBS_peek_last_u8(CBS *cbs, uint8_t *out);
/* Parsing ASN.1 */
/*
* While an identifier can be multiple octets, this library only handles the
* single octet variety currently. This limits support up to tag number 30
* since tag number 31 is a reserved value to indicate multiple octets.
*/
/* Bits 8 and 7: class tag type: See X.690 section 8.1.2.2. */
#define CBS_ASN1_UNIVERSAL 0x00
#define CBS_ASN1_APPLICATION 0x40
#define CBS_ASN1_CONTEXT_SPECIFIC 0x80
#define CBS_ASN1_PRIVATE 0xc0
/* Bit 6: Primitive or constructed: See X.690 section 8.1.2.3. */
#define CBS_ASN1_PRIMITIVE 0x00
#define CBS_ASN1_CONSTRUCTED 0x20
/*
* Bits 5 to 1 are the tag number. See X.680 section 8.6 for tag numbers of
* the universal class.
*/
/*
* Common universal identifier octets.
* See X.690 section 8.1 and X.680 section 8.6 for universal tag numbers.
*
* Note: These definitions are the cause of some of the strange behavior in
* CBS's bs_ber.c.
*
* In BER, it is the sender's option to use primitive or constructed for
* bitstring (X.690 section 8.6.1) and octetstring (X.690 section 8.7.1).
*
* In DER, bitstring and octetstring are required to be primitive
* (X.690 section 10.2).
*/
#define CBS_ASN1_BOOLEAN (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x1)
#define CBS_ASN1_INTEGER (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x2)
#define CBS_ASN1_BITSTRING (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x3)
#define CBS_ASN1_OCTETSTRING (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x4)
#define CBS_ASN1_OBJECT (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0x6)
#define CBS_ASN1_ENUMERATED (CBS_ASN1_UNIVERSAL | CBS_ASN1_PRIMITIVE | 0xa)
#define CBS_ASN1_SEQUENCE (CBS_ASN1_UNIVERSAL | CBS_ASN1_CONSTRUCTED | 0x10)
#define CBS_ASN1_SET (CBS_ASN1_UNIVERSAL | CBS_ASN1_CONSTRUCTED | 0x11)
/*
* CBS_get_asn1 sets |*out| to the contents of DER-encoded, ASN.1 element (not
* including tag and length bytes) and advances |cbs| over it. The ASN.1
* element must match |tag_value|. It returns one on success and zero
* on error.
*
* Tag numbers greater than 30 are not supported (i.e. short form only).
*/
int CBS_get_asn1(CBS *cbs, CBS *out, unsigned int tag_value);
/*
* CBS_get_asn1_element acts like |CBS_get_asn1| but |out| will include the
* ASN.1 header bytes too.
*/
int CBS_get_asn1_element(CBS *cbs, CBS *out, unsigned int tag_value);
/*
* CBS_peek_asn1_tag looks ahead at the next ASN.1 tag and returns one
* if the next ASN.1 element on |cbs| would have tag |tag_value|. If
* |cbs| is empty or the tag does not match, it returns zero. Note: if
* it returns one, CBS_get_asn1 may still fail if the rest of the
* element is malformed.
*/
int CBS_peek_asn1_tag(const CBS *cbs, unsigned int tag_value);
/*
* CBS_get_any_asn1_element sets |*out| to contain the next ASN.1 element from
* |*cbs| (including header bytes) and advances |*cbs|. It sets |*out_tag| to
* the tag number and |*out_header_len| to the length of the ASN.1 header.
* Each of |out|, |out_tag|, and |out_header_len| may be NULL to ignore
* the value.
*
* Tag numbers greater than 30 are not supported (i.e. short form only).
*/
int CBS_get_any_asn1_element(CBS *cbs, CBS *out, unsigned int *out_tag,
size_t *out_header_len);
/*
* CBS_get_asn1_uint64 gets an ASN.1 INTEGER from |cbs| using |CBS_get_asn1|
* and sets |*out| to its value. It returns one on success and zero on error,
* where error includes the integer being negative, or too large to represent
* in 64 bits.
*/
int CBS_get_asn1_uint64(CBS *cbs, uint64_t *out);
/*
* CBS_get_optional_asn1 gets an optional explicitly-tagged element
* from |cbs| tagged with |tag| and sets |*out| to its contents. If
* present, it sets |*out_present| to one, otherwise zero. It returns
* one on success, whether or not the element was present, and zero on
* decode failure.
*/
int CBS_get_optional_asn1(CBS *cbs, CBS *out, int *out_present,
unsigned int tag);
/*
* CBS_get_optional_asn1_octet_string gets an optional
* explicitly-tagged OCTET STRING from |cbs|. If present, it sets
* |*out| to the string and |*out_present| to one. Otherwise, it sets
* |*out| to empty and |*out_present| to zero. |out_present| may be
* NULL. It returns one on success, whether or not the element was
* present, and zero on decode failure.
*/
int CBS_get_optional_asn1_octet_string(CBS *cbs, CBS *out, int *out_present,
unsigned int tag);
/*
* CBS_get_optional_asn1_uint64 gets an optional explicitly-tagged
* INTEGER from |cbs|. If present, it sets |*out| to the
* value. Otherwise, it sets |*out| to |default_value|. It returns one
* on success, whether or not the element was present, and zero on
* decode failure.
*/
int CBS_get_optional_asn1_uint64(CBS *cbs, uint64_t *out, unsigned int tag,
uint64_t default_value);
/*
* CBS_get_optional_asn1_bool gets an optional, explicitly-tagged BOOLEAN from
* |cbs|. If present, it sets |*out| to either zero or one, based on the
* boolean. Otherwise, it sets |*out| to |default_value|. It returns one on
* success, whether or not the element was present, and zero on decode
* failure.
*/
int CBS_get_optional_asn1_bool(CBS *cbs, int *out, unsigned int tag,
int default_value);
/*
* CRYPTO ByteBuilder.
*
* |CBB| objects allow one to build length-prefixed serialisations. A |CBB|
* object is associated with a buffer and new buffers are created with
* |CBB_init|. Several |CBB| objects can point at the same buffer when a
* length-prefix is pending, however only a single |CBB| can be 'current' at
* any one time. For example, if one calls |CBB_add_u8_length_prefixed| then
* the new |CBB| points at the same buffer as the original. But if the original
* |CBB| is used then the length prefix is written out and the new |CBB| must
* not be used again.
*
* If one needs to force a length prefix to be written out because a |CBB| is
* going out of scope, use |CBB_flush|.
*/
struct cbb_buffer_st {
uint8_t *buf;
/* The number of valid bytes. */
size_t len;
/* The size of buf. */
size_t cap;
/*
* One iff |buf| is owned by this object. If not then |buf| cannot be
* resized.
*/
char can_resize;
};
typedef struct cbb_st {
struct cbb_buffer_st *base;
/*
* offset is the offset from the start of |base->buf| to the position of any
* pending length-prefix.
*/
size_t offset;
/* child points to a child CBB if a length-prefix is pending. */
struct cbb_st *child;
/*
* pending_len_len contains the number of bytes in a pending length-prefix,
* or zero if no length-prefix is pending.
*/
uint8_t pending_len_len;
char pending_is_asn1;
/*
* is_top_level is true iff this is a top-level |CBB| (as opposed to a child
* |CBB|). Top-level objects are valid arguments for |CBB_finish|.
*/
char is_top_level;
} CBB;
/*
* CBB_init initialises |cbb| with |initial_capacity|. Since a |CBB| grows as
* needed, the |initial_capacity| is just a hint. It returns one on success or
* zero on error.
*/
int CBB_init(CBB *cbb, size_t initial_capacity);
/*
* CBB_init_fixed initialises |cbb| to write to |len| bytes at |buf|. Since
* |buf| cannot grow, trying to write more than |len| bytes will cause CBB
* functions to fail. It returns one on success or zero on error.
*/
int CBB_init_fixed(CBB *cbb, uint8_t *buf, size_t len);
/*
* CBB_cleanup frees all resources owned by |cbb| and other |CBB| objects
* writing to the same buffer. This should be used in an error case where a
* serialisation is abandoned.
*/
void CBB_cleanup(CBB *cbb);
/*
* CBB_finish completes any pending length prefix and sets |*out_data| to a
* malloced buffer and |*out_len| to the length of that buffer. The caller
* takes ownership of the buffer and, unless the buffer was fixed with
* |CBB_init_fixed|, must call |free| when done.
*
* It can only be called on a "top level" |CBB|, i.e. one initialised with
* |CBB_init| or |CBB_init_fixed|. It returns one on success and zero on
* error.
*/
int CBB_finish(CBB *cbb, uint8_t **out_data, size_t *out_len);
/*
* CBB_flush causes any pending length prefixes to be written out and any child
* |CBB| objects of |cbb| to be invalidated. It returns one on success or zero
* on error.
*/
int CBB_flush(CBB *cbb);
/*
* CBB_discard_child discards the current unflushed child of |cbb|. Neither the
* child's contents nor the length prefix will be included in the output.
*/
void CBB_discard_child(CBB *cbb);
/*
* CBB_add_u8_length_prefixed sets |*out_contents| to a new child of |cbb|. The
* data written to |*out_contents| will be prefixed in |cbb| with an 8-bit
* length. It returns one on success or zero on error.
*/
int CBB_add_u8_length_prefixed(CBB *cbb, CBB *out_contents);
/*
* CBB_add_u16_length_prefixed sets |*out_contents| to a new child of |cbb|.
* The data written to |*out_contents| will be prefixed in |cbb| with a 16-bit,
* big-endian length. It returns one on success or zero on error.
*/
int CBB_add_u16_length_prefixed(CBB *cbb, CBB *out_contents);
/*
* CBB_add_u24_length_prefixed sets |*out_contents| to a new child of |cbb|.
* The data written to |*out_contents| will be prefixed in |cbb| with a 24-bit,
* big-endian length. It returns one on success or zero on error.
*/
int CBB_add_u24_length_prefixed(CBB *cbb, CBB *out_contents);
/*
* CBB_add_asn sets |*out_contents| to a |CBB| into which the contents of an
* ASN.1 object can be written. The |tag| argument will be used as the tag for
* the object. Passing in |tag| number 31 will return in an error since only
* single octet identifiers are supported. It returns one on success or zero
* on error.
*/
int CBB_add_asn1(CBB *cbb, CBB *out_contents, unsigned int tag);
/*
* CBB_add_bytes appends |len| bytes from |data| to |cbb|. It returns one on
* success and zero otherwise.
*/
int CBB_add_bytes(CBB *cbb, const uint8_t *data, size_t len);
/*
* CBB_add_space appends |len| bytes to |cbb| and sets |*out_data| to point to
* the beginning of that space. The caller must then write |len| bytes of
* actual contents to |*out_data|. It returns one on success and zero
* otherwise.
*/
int CBB_add_space(CBB *cbb, uint8_t **out_data, size_t len);
/*
* CBB_add_u8 appends an 8-bit number from |value| to |cbb|. It returns one on
* success and zero otherwise.
*/
int CBB_add_u8(CBB *cbb, size_t value);
/*
* CBB_add_u8 appends a 16-bit, big-endian number from |value| to |cbb|. It
* returns one on success and zero otherwise.
*/
int CBB_add_u16(CBB *cbb, size_t value);
/*
* CBB_add_u24 appends a 24-bit, big-endian number from |value| to |cbb|. It
* returns one on success and zero otherwise.
*/
int CBB_add_u24(CBB *cbb, size_t value);
/*
* CBB_add_u32 appends a 32-bit, big-endian number from |value| to |cbb|. It
* returns one on success and zero otherwise.
*/
int CBB_add_u32(CBB *cbb, size_t value);
/*
* CBB_add_u64 appends a 64-bit, big-endian number from |value| to |cbb|. It
* returns one on success and zero otherwise.
*/
int CBB_add_u64(CBB *cbb, uint64_t value);
/*
* CBB_add_asn1_uint64 writes an ASN.1 INTEGER into |cbb| using |CBB_add_asn1|
* and writes |value| in its contents. It returns one on success and zero on
* error.
*/
int CBB_add_asn1_uint64(CBB *cbb, uint64_t value);
#ifdef LIBRESSL_INTERNAL
/*
* CBS_dup sets |out| to point to cbs's |data| and |len|. It results in two
* CBS that point to the same buffer.
*/
void CBS_dup(const CBS *cbs, CBS *out);
/*
* cbs_get_any_asn1_element sets |*out| to contain the next ASN.1 element from
* |*cbs| (including header bytes) and advances |*cbs|. It sets |*out_tag| to
* the tag number and |*out_header_len| to the length of the ASN.1 header. If
* strict mode is disabled and the element has indefinite length then |*out|
* will only contain the header. Each of |out|, |out_tag|, and
* |out_header_len| may be NULL to ignore the value.
*
* Tag numbers greater than 30 are not supported (i.e. short form only).
*/
int cbs_get_any_asn1_element_internal(CBS *cbs, CBS *out, unsigned int *out_tag,
size_t *out_header_len, int strict);
/*
* CBS_asn1_indefinite_to_definite reads an ASN.1 structure from |in|. If it
* finds indefinite-length elements that otherwise appear to be valid DER, it
* attempts to convert the DER-like data to DER and sets |*out| and
* |*out_length| to describe a malloced buffer containing the DER data.
* Additionally, |*in| will be advanced over the ASN.1 data.
*
* If it doesn't find any indefinite-length elements then it sets |*out| to
* NULL and |*in| is unmodified.
*
* This is NOT a conversion from BER to DER. There are many restrictions when
* dealing with DER data. This is only concerned with one: indefinite vs.
* definite form. However, this suffices to handle the PKCS#7 and PKCS#12 output
* from NSS.
*
* It returns one on success and zero otherwise.
*/
int CBS_asn1_indefinite_to_definite(CBS *in, uint8_t **out, size_t *out_len);
#endif /* LIBRESSL_INTERNAL */
__END_HIDDEN_DECLS
#endif /* OPENSSL_HEADER_BYTESTRING_H */