cscg24-guacamole

CSCG 2024 Challenge 'Guacamole Mashup'
git clone https://git.sinitax.com/sinitax/cscg24-guacamole
Log | Files | Refs | sfeed.txt

lws-cose.h (15637B)


      1/*
      2 * libwebsockets - small server side websockets and web server implementation
      3 *
      4 * Copyright (C) 2010 - 2021 Andy Green <andy@warmcat.com>
      5 *
      6 * Permission is hereby granted, free of charge, to any person obtaining a copy
      7 * of this software and associated documentation files (the "Software"), to
      8 * deal in the Software without restriction, including without limitation the
      9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
     10 * sell copies of the Software, and to permit persons to whom the Software is
     11 * furnished to do so, subject to the following conditions:
     12 *
     13 * The above copyright notice and this permission notice shall be included in
     14 * all copies or substantial portions of the Software.
     15 *
     16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
     18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
     19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
     20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
     21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
     22 * IN THE SOFTWARE.
     23 */
     24
     25/** \defgroup cose COSE apis
     26 * ##COSE related functions
     27 * \ingroup lwsaoi
     28 *
     29 * COSE RFC 8152 relates to signed and encrypted CBOR
     30 */
     31//@{
     32
     33enum {
     34	/*  RFC8152: Table 2: Common Header Parameters
     35	 * https://www.iana.org/assignments/cose/cose.xhtml#header-parameters
     36	 */
     37
     38	LWSCOSE_WKL_ALG				= 1,   /* int / tstr */
     39	LWSCOSE_WKL_CRIT,			       /* [+ label ] */
     40	LWSCOSE_WKL_CONTENT_TYPE,		       /* tstr / uint */
     41	LWSCOSE_WKL_KID,			       /* bstr */
     42	LWSCOSE_WKL_IV,				       /* bstr */
     43	LWSCOSE_WKL_IV_PARTIAL,			       /* bstr */
     44	LWSCOSE_WKL_COUNTERSIG,			       /* COSE sig(s) */
     45	LWSCOSE_WKL_COUNTERSIG0			= 9,   /* bstr */
     46	LWSCOSE_WKL_KID_CONTEXT,		       /* bstr */
     47	LWSCOSE_WKL_CUPH_NONCE			= 256, /* bstr */
     48	LWSCOSE_WKL_CUPH_OWNER_PUBKEY		= 257, /* array */
     49
     50	/*  RFC8152: Table 3: key map labels */
     51
     52	LWSCOSE_WKK_KTY				= 1, /* int / tstr */
     53	LWSCOSE_WKK_KID,			     /* bstr */
     54	LWSCOSE_WKK_ALG,			     /* int / tstr */
     55	LWSCOSE_WKK_KEY_OPS,			     /* [ + (int / tstr) ] */
     56	LWSCOSE_WKK_BASE_IV,			     /* bstr */
     57
     58	/*  RFC8152: Table 4: Key Operation Values */
     59
     60	LWSCOSE_WKKO_SIGN			= 1,
     61	LWSCOSE_WKKO_VERIFY,
     62	LWSCOSE_WKKO_ENCRYPT,
     63	LWSCOSE_WKKO_DECRYPT,
     64	LWSCOSE_WKKO_WRAP_KEY,
     65	LWSCOSE_WKKO_UNWRAP_KEY,
     66	LWSCOSE_WKKO_DERIVE_KEY,
     67	LWSCOSE_WKKO_DERIVE_BITS,
     68	LWSCOSE_WKKO_MAC_CREATE,
     69	LWSCOSE_WKKO_MAC_VERIFY,
     70
     71	/*  RFC8152: Table 5: ECDSA algs */
     72
     73	LWSCOSE_WKAECDSA_ALG_ES256		= -7,
     74	LWSCOSE_WKAECDSA_ALG_ES384		= -35,
     75	LWSCOSE_WKAECDSA_ALG_ES512		= -36,
     76
     77	/*  RFC8152: Table 6: EDDSA algs */
     78
     79	LWSCOSE_WKAEDDSA_ALG_EDDSA		= -8,
     80
     81	/*  RFC8152: Table 7: HMAC algs */
     82
     83	LWSCOSE_WKAHMAC_256_64			= 4,
     84	LWSCOSE_WKAHMAC_256_256,
     85	LWSCOSE_WKAHMAC_384_384,
     86	LWSCOSE_WKAHMAC_512_512,
     87
     88	/*  RFC8152: Table 8: AES algs */
     89
     90	LWSCOSE_WKAAES_128_64			= 14,
     91	LWSCOSE_WKAAES_256_64,
     92	LWSCOSE_WKAAES_128_128			= 25,
     93	LWSCOSE_WKAAES_256_128,
     94
     95	/*  RFC8152: Table 9: AES GCM algs */
     96
     97	LWSCOSE_WKAAESGCM_128			= 1,
     98	LWSCOSE_WKAAESGCM_192,
     99	LWSCOSE_WKAAESGCM_256,
    100
    101	/*  RFC8152: Table 10: AES CCM algs */
    102
    103	LWSCOSE_WKAAESCCM_16_64_128		= 10,
    104	LWSCOSE_WKAAESCCM_16_64_256,
    105	LWSCOSE_WKAAESCCM_64_64_128,
    106	LWSCOSE_WKAAESCCM_64_64_256,
    107	LWSCOSE_WKAAESCCM_16_128_128,
    108	LWSCOSE_WKAAESCCM_16_128_256,
    109	LWSCOSE_WKAAESCCM_64_128_128,
    110	LWSCOSE_WKAAESCCM_64_128_256,
    111
    112	/*  RFC8152: Table 11: CHACHA20 / Poly1305 */
    113
    114	LWSCOSE_WKACHACHA_POLY1305		= 24,
    115
    116	/*  RFC8152: Table 13: HKDF param */
    117
    118	LWSCOSE_WKAPHKDF_SALT			= -20,
    119
    120	/* RFC8152: Table 14: Context Algorithm Parameters */
    121
    122	LWSCOSE_WKAPCTX_PARTY_U_IDENTITY	= -21,
    123	LWSCOSE_WKAPCTX_PARTY_U_NONCE		= -22,
    124	LWSCOSE_WKAPCTX_PARTY_U_OTHER		= -23,
    125	LWSCOSE_WKAPCTX_PARTY_V_IDENTITY	= -24,
    126	LWSCOSE_WKAPCTX_PARTY_V_NONCE		= -25,
    127	LWSCOSE_WKAPCTX_PARTY_V_OTHER		= -26,
    128
    129	/* RFC8152: Table 15: Direct key */
    130
    131	LWSCOSE_WKK_DIRECT_CEK			= -6,
    132
    133	/* RFC8152: Table 16: Direct key with KDF */
    134
    135	LWSCOSE_WKK_DIRECT_HKDF_SHA_256		= -10,
    136	LWSCOSE_WKK_DIRECT_HKDF_SHA_512		= -11,
    137	LWSCOSE_WKK_DIRECT_HKDF_AES_128		= -12,
    138	LWSCOSE_WKK_DIRECT_HKDF_AES_256		= -13,
    139
    140	/* RFC8152: Table 17: AES Key Wrap Algorithm Values */
    141
    142	LWSCOSE_WKK_DIRECT_HKDFKW_SHA_256	= -3,
    143	LWSCOSE_WKK_DIRECT_HKDFKW_SHA_512	= -4,
    144	LWSCOSE_WKK_DIRECT_HKDFKW_AES_128	= -5,
    145
    146	/* RFC8152: Table 18: ECDH Algorithm Values */
    147
    148	LWSCOSE_WKAECDH_ALG_ES_HKDF_256		= -25,
    149	LWSCOSE_WKAECDH_ALG_ES_HKDF_512		= -26,
    150	LWSCOSE_WKAECDH_ALG_SS_HKDF_256		= -27,
    151	LWSCOSE_WKAECDH_ALG_SS_HKDF_512		= -28,
    152
    153	/* RFC8152: Table 19: ECDH Algorithm Parameters */
    154
    155	LWSCOSE_WKAPECDH_EPHEMERAL_KEY		= -1,
    156	LWSCOSE_WKAPECDH_STATIC_KEY		= -2,
    157	LWSCOSE_WKAPECDH_STATIC_KEY_ID		= -3,
    158
    159	/* RFC8152: Table 20: ECDH Algorithm Parameters with key wrap */
    160
    161	LWSCOSE_WKAPECDH_ES_A128KW		= -29,
    162	LWSCOSE_WKAPECDH_ES_A192KW		= -30,
    163	LWSCOSE_WKAPECDH_ES_A256KW		= -31,
    164	LWSCOSE_WKAPECDH_SS_A128KW		= -32,
    165	LWSCOSE_WKAPECDH_SS_A192KW		= -33,
    166	LWSCOSE_WKAPECDH_SS_A256KW		= -34,
    167
    168	/* RFC8152: Table 21: Key Type Values
    169	 *  https://www.iana.org/assignments/cose/cose.xhtml#key-type
    170	 */
    171
    172	LWSCOSE_WKKTV_OKP			= 1,
    173	LWSCOSE_WKKTV_EC2			= 2,
    174	LWSCOSE_WKKTV_RSA			= 3,
    175	LWSCOSE_WKKTV_SYMMETRIC			= 4,
    176	LWSCOSE_WKKTV_HSS_LMS			= 5,
    177	LWSCOSE_WKKTV_WALNUTDSA			= 6,
    178
    179
    180	/* RFC8152: Table 22: Elliptic Curves
    181	 * https://www.iana.org/assignments/cose/cose.xhtml#elliptic-curves
    182	 */
    183
    184	LWSCOSE_WKEC_P256			= 1,
    185	LWSCOSE_WKEC_P384,
    186	LWSCOSE_WKEC_P521,
    187	LWSCOSE_WKEC_X25519,
    188	LWSCOSE_WKEC_X448,
    189	LWSCOSE_WKEC_ED25519,
    190	LWSCOSE_WKEC_ED448,
    191	LWSCOSE_WKEC_SECP256K1,
    192
    193	/* RFC8152: Table 23: EC Key Parameters */
    194
    195	LWSCOSE_WKECKP_CRV			= -1,
    196	LWSCOSE_WKECKP_X			= -2,
    197	LWSCOSE_WKECKP_Y			= -3,
    198	LWSCOSE_WKECKP_D			= -4,
    199
    200	/* RFC8152: Table 24: Octet Key Pair (OKP) Parameters */
    201
    202	LWSCOSE_WKOKP_CRV			= -1,
    203	LWSCOSE_WKOKP_X				= -2,
    204	LWSCOSE_WKOKP_D				= -4,
    205
    206	/* Additional from
    207	 * https://www.iana.org/assignments/cose/cose.xhtml#key-type-parameters
    208	 */
    209
    210	LWSCOSE_WKKPRSA_N			= -1,
    211	LWSCOSE_WKKPRSA_E			= -2,
    212	LWSCOSE_WKKPRSA_D			= -3,
    213	LWSCOSE_WKKPRSA_P			= -4,
    214	LWSCOSE_WKKPRSA_Q			= -5,
    215	LWSCOSE_WKKPRSA_DP			= -6,
    216	LWSCOSE_WKKPRSA_DQ			= -7,
    217	LWSCOSE_WKKPRSA_QINV			= -8,
    218	LWSCOSE_WKKPRSA_OTHER			= -9,
    219	LWSCOSE_WKKPRSA_RI			= -10,
    220	LWSCOSE_WKKPRSA_DI			= -11,
    221	LWSCOSE_WKKPRSA_TI			= -12,
    222
    223	/* RFC8152: Table 25: Symmetric Key Parameters */
    224
    225	LWSCOSE_WKSYMKP_KEY_VALUE		= 4,
    226
    227	/* RFC8152: Table 26: CoAP Content-Formats for COSE */
    228
    229	LWSCOAP_CONTENTFORMAT_COSE_SIGN		= 98,
    230	LWSCOAP_CONTENTFORMAT_COSE_SIGN1	= 18,
    231	LWSCOAP_CONTENTFORMAT_COSE_ENCRYPT	= 96,
    232	LWSCOAP_CONTENTFORMAT_COSE_ENCRYPT0	= 16,
    233	LWSCOAP_CONTENTFORMAT_COSE_MAC		= 97,
    234	LWSCOAP_CONTENTFORMAT_COSE_MAC0		= 17,
    235	LWSCOAP_CONTENTFORMAT_COSE_KEY		= 101,
    236	LWSCOAP_CONTENTFORMAT_COSE_KEY_SET	= 102,
    237
    238	/* RFC8152: Table 27: Header Parameter for CounterSignature0 */
    239
    240	LWSCOSE_WKL_COUNTERSIGNATURE0		= 9, /* bstr */
    241
    242	/* RFC8812: Table 1: RSASSA-PKCS1-v1_5 Algorithm Values */
    243
    244	LWSCOSE_WKARSA_ALG_RS256		= -257, /* + SHA-256 */
    245	LWSCOSE_WKARSA_ALG_RS384		= -258, /* + SHA-384 */
    246	LWSCOSE_WKARSA_ALG_RS512		= -259, /* + SHA-512 */
    247};
    248
    249enum enum_cose_key_meta_tok {
    250	COSEKEY_META_KTY,
    251	COSEKEY_META_KID,
    252	COSEKEY_META_KEY_OPS,
    253	COSEKEY_META_BASE_IV,
    254	COSEKEY_META_ALG,
    255
    256	LWS_COUNT_COSE_KEY_ELEMENTS
    257};
    258
    259typedef int64_t cose_param_t;
    260
    261LWS_VISIBLE LWS_EXTERN const char *
    262lws_cose_alg_to_name(cose_param_t alg);
    263
    264LWS_VISIBLE LWS_EXTERN cose_param_t
    265lws_cose_name_to_alg(const char *name);
    266
    267/*
    268 * cose_key
    269 */
    270
    271typedef struct lws_cose_key {
    272	/* key data elements */
    273	struct lws_gencrypto_keyelem	e[LWS_GENCRYPTO_MAX_KEYEL_COUNT];
    274	/* generic meta key elements, like KID */
    275	struct lws_gencrypto_keyelem 	meta[LWS_COUNT_COSE_KEY_ELEMENTS];
    276	lws_dll2_t			list; /* used when part of a set */
    277	int				gencrypto_kty;	/**< one of LWS_GENCRYPTO_KTY_ */
    278	cose_param_t			kty;
    279	cose_param_t			cose_alg;
    280	cose_param_t			cose_curve;
    281	char 				private_key; /* nonzero = has private key elements */
    282} lws_cose_key_t;
    283
    284typedef int (*lws_cose_key_import_callback)(struct lws_cose_key *s, void *user);
    285
    286/** lws_cose_jwk_import() - Create an lws_cose_key_t object from cose_key CBOR
    287 *
    288 * \param pkey_set: NULL, or a pointer to an lws_dll2_owner_t for a cose_key set
    289 * \param cb: callback for each jwk-processed key, or NULL if importing a single
    290 *	      key with no parent "keys" JSON
    291 * \param user: pointer to be passed to the callback, otherwise ignored by lws.
    292 *		NULL if importing a single key with no parent "keys" JSON
    293 * \param in: a single cose_key
    294 * \param len: the length of the cose_key in bytes
    295 *
    296 * Creates a single lws_cose_key_t if \p pkey_set is NULL or if the incoming
    297 * CBOR doesn't start with an array, otherwise expects a CBOR array containing
    298 * zero or more cose_key CBOR, and adds each to the \p pkey_set
    299 * lws_dll2_owner_t struct.  Created lws_cose_key_t are filled with data from
    300 * the COSE representation and can be used with other COSE crypto ops.
    301 */
    302LWS_VISIBLE LWS_EXTERN lws_cose_key_t *
    303lws_cose_key_import(lws_dll2_owner_t *pkey_set, lws_cose_key_import_callback cb,
    304		    void *user, const uint8_t *in, size_t len);
    305
    306/** lws_cose_key_export() - Create cose_key CBOR from an lws_cose_key_t
    307 *
    308 * \param ck: the lws_cose_key_t to export to CBOR
    309 * \param ctx: the CBOR writing context (same as for lws_lec_printf())
    310 * \param flags: 0 to export only public elements, or LWSJWKF_EXPORT_PRIVATE
    311 *
    312 * Creates an lws_jwk struct filled with data from the COSE representation.
    313 */
    314LWS_VISIBLE LWS_EXTERN enum lws_lec_pctx_ret
    315lws_cose_key_export(lws_cose_key_t *ck, lws_lec_pctx_t *ctx, int flags);
    316
    317/**
    318 * lws_cose_key_generate() - generate a fresh key
    319 *
    320 * \param context: the lws_context used to get random
    321 * \param cose_kty: one of LWSCOSE_WKKTV_ indicating the well-known key type
    322 * \param use_mask: 0, or a bitfield where (1 << LWSCOSE_WKKO_...) set means valid for use
    323 * \param bits: key bits for RSA
    324 * \param curve: for EC keys, one of "P-256", "P-384" or "P-521" currently
    325 * \param kid: string describing the key, or NULL
    326 *
    327 * Create an lws_cose_key_t of the specified type and return it
    328 */
    329LWS_VISIBLE LWS_EXTERN lws_cose_key_t *
    330lws_cose_key_generate(struct lws_context *context, cose_param_t cose_kty,
    331		      int use_mask, int bits, const char *curve,
    332		      const uint8_t *kid, size_t kl);
    333
    334LWS_VISIBLE LWS_EXTERN lws_cose_key_t *
    335lws_cose_key_from_set(lws_dll2_owner_t *set, const uint8_t *kid, size_t kl);
    336
    337LWS_VISIBLE LWS_EXTERN void
    338lws_cose_key_destroy(lws_cose_key_t **ck);
    339
    340LWS_VISIBLE LWS_EXTERN void
    341lws_cose_key_set_destroy(lws_dll2_owner_t *o);
    342
    343/* only available in _DEBUG build */
    344
    345LWS_VISIBLE LWS_EXTERN void
    346lws_cose_key_dump(const lws_cose_key_t *ck);
    347
    348/*
    349 * cose_sign
    350 */
    351
    352struct lws_cose_validate_context;
    353
    354
    355enum lws_cose_sig_types {
    356	SIGTYPE_UNKNOWN,
    357	SIGTYPE_MULTI,
    358	SIGTYPE_SINGLE,
    359	SIGTYPE_COUNTERSIGNED, /* not yet supported */
    360	SIGTYPE_MAC, /* only supported for validation */
    361	SIGTYPE_MAC0,
    362};
    363
    364/* a list of these result objects is the output of the validation process */
    365
    366typedef struct {
    367	lws_dll2_t		list;
    368
    369	const lws_cose_key_t	*cose_key;
    370	cose_param_t		cose_alg;
    371
    372	int			result; /* 0 = validated */
    373
    374} lws_cose_validate_res_t;
    375
    376enum {
    377	LCOSESIGEXTCB_RET_FINISHED,
    378	LCOSESIGEXTCB_RET_AGAIN,
    379	LCOSESIGEXTCB_RET_ERROR		= -1
    380};
    381
    382typedef struct {
    383	struct lws_cose_validate_context *cps;
    384	const uint8_t			 *ext;
    385	size_t				 xl;
    386} lws_cose_sig_ext_pay_t;
    387
    388typedef int (*lws_cose_sign_ext_pay_cb_t)(lws_cose_sig_ext_pay_t *x);
    389typedef int (*lws_cose_validate_pay_cb_t)(struct lws_cose_validate_context *cps,
    390					  void *opaque, const uint8_t *paychunk,
    391					  size_t paychunk_len);
    392
    393typedef struct lws_cose_validate_create_info {
    394	struct lws_context		*cx;
    395	/**< REQUIRED: the lws context */
    396	lws_dll2_owner_t		*keyset;
    397	/**< REQUIRED: one or more cose_keys */
    398
    399	enum lws_cose_sig_types		sigtype;
    400	/**<  0 if a CBOR tag is in the sig, else one of SIGTYPE_MULTI,
    401	 * SIGTYPE_SINGLE, etc*/
    402
    403	lws_cose_validate_pay_cb_t	pay_cb;
    404	/**< optional: called back with unvalidated payload pieces */
    405	void				*pay_opaque;
    406	/**< optional: passed into pay_cb callback along with payload chunk */
    407
    408	lws_cose_sign_ext_pay_cb_t	ext_cb;
    409	/**< optional extra application data provision callback */
    410	void				*ext_opaque;
    411	/**< optional extra application data provision callback opaque */
    412	size_t				ext_len;
    413	/**< if we have extra app data, this must be set to the length of it */
    414} lws_cose_validate_create_info_t;
    415
    416/**
    417 * lws_cose_validate_create() - create a signature validation context
    418 *
    419 * \param info: struct describing the validation context to create
    420 *
    421 * Creates a signature validation context set up as described in \p info.
    422 *
    423 * You can then pass the signature cbor chunks to it using
    424 * lws_cose_validate_chunk(), finialize and get the results list using
    425 * lws_cose_validate_results() and destroy with lws_cose_validate_destroy().
    426 */
    427LWS_VISIBLE LWS_EXTERN struct lws_cose_validate_context *
    428lws_cose_validate_create(const lws_cose_validate_create_info_t *info);
    429
    430/**
    431 * lws_cose_validate_chunk() - passes chunks of CBOR into the signature validator
    432 *
    433 * \param cps: the validation context
    434 * \param in: the chunk of CBOR (does not have to be logically complete)
    435 * \param in_len: number of bytes available at \p in
    436 *
    437 * Parses signature CBOR to produce a list of result objects.
    438 *
    439 *
    440 */
    441LWS_VISIBLE LWS_EXTERN int
    442lws_cose_validate_chunk(struct lws_cose_validate_context *cps,
    443			const uint8_t *in, size_t in_len, size_t *used_in);
    444
    445LWS_VISIBLE LWS_EXTERN lws_dll2_owner_t *
    446lws_cose_validate_results(struct lws_cose_validate_context *cps);
    447
    448LWS_VISIBLE LWS_EXTERN void
    449lws_cose_validate_destroy(struct lws_cose_validate_context **cps);
    450
    451struct lws_cose_sign_context;
    452
    453#define LCSC_FL_ADD_CBOR_TAG		(1 << 0)
    454#define LCSC_FL_ADD_CBOR_PREFER_MAC0	(1 << 1)
    455
    456typedef struct lws_cose_sign_create_info {
    457	struct lws_context		*cx;
    458	/**< REQUIRED: the lws context */
    459	lws_dll2_owner_t		*keyset;
    460	/**< REQUIRED: one or more cose_keys */
    461
    462	lws_lec_pctx_t			*lec;
    463	/**< REQUIRED: the cbor output context to emit to, user must
    464	 * initialize with lws_lec_init() beforehand */
    465
    466	lws_cose_sign_ext_pay_cb_t	ext_cb;
    467	/**< optional extra application data provision callback */
    468	void				*ext_opaque;
    469	/**< optional extra application data provision callback opaque */
    470	size_t				ext_len;
    471	/**< if we have extra app data, this must be set to the length of it */
    472
    473	size_t				inline_payload_len;
    474	/**< REQUIRED: size of the inline payload we will provide */
    475
    476	int				flags;
    477	/**< bitmap of  LCSC_FL_* */
    478	enum lws_cose_sig_types		sigtype;
    479	/**< 0, or sign type hint */
    480} lws_cose_sign_create_info_t;
    481
    482/**
    483 * lws_cose_sign_create() - Create a signing context
    484 *
    485 * \param info: a structure describing the signing context you want to create
    486 *
    487 * This allocates and returns a signing context created according to what is in
    488 * the \p info parameter.
    489 *
    490 * \p info must be prepared with the lws_context, a keyset to use, a CBOR
    491 * output context, and the inline payload length.
    492 *
    493 * Returns NULL on failure or the created signing context ready to add alg(s)
    494 * to.
    495 */
    496
    497LWS_VISIBLE LWS_EXTERN struct lws_cose_sign_context *
    498lws_cose_sign_create(const lws_cose_sign_create_info_t *info);
    499
    500LWS_VISIBLE LWS_EXTERN int
    501lws_cose_sign_add(struct lws_cose_sign_context *csc, cose_param_t alg,
    502		  const lws_cose_key_t *ck);
    503
    504LWS_VISIBLE LWS_EXTERN enum lws_lec_pctx_ret
    505lws_cose_sign_payload_chunk(struct lws_cose_sign_context *csc,
    506			    const uint8_t *in, size_t in_len);
    507
    508LWS_VISIBLE LWS_EXTERN void
    509lws_cose_sign_destroy(struct lws_cose_sign_context **csc);
    510
    511//@}