src/Encrypt.c - third_party/github/cose-wg/COSE-C - Git at Google

 #include <stdlib.h>
 #include <memory.h>
 #include <stdio.h>
 #include <assert.h>

 #include "cose.h"
 #include "cose_int.h"
 #include "configure.h"
 #include "crypto.h"

 byte RgbDontUse[8 * 1024];   //  Remove this array when we can compute the size of a cbor serialization without this hack.


 bool IsValidEncryptHandle(HCOSE_ENCRYPT h)
 {
 	COSE_Encrypt * p = (COSE_Encrypt *)h;
 	if (p == NULL) return false;
 	return true;
 }


 size_t COSE_Encode(HCOSE msg, byte * rgb, int ib, size_t cb)
 {
 	if (rgb == NULL) return cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), ((COSE *)msg)->m_cbor) + ib;
 	return cn_cbor_encoder_write(rgb, ib, cb, ((COSE*)msg)->m_cbor);
 }

 HCOSE_ENCRYPT COSE_Encrypt_Init(CBOR_CONTEXT_COMMA cose_errback * perror)
 {
 	COSE_Encrypt * pobj = (COSE_Encrypt *)COSE_CALLOC(1, sizeof(COSE_Encrypt), context);
 	if (pobj == NULL) {
 		if (perror != NULL) perror->err = COSE_ERR_OUT_OF_MEMORY;
 		return NULL;
 	}

 	if (!_COSE_Init(&pobj->m_message, CBOR_CONTEXT_PARAM_COMMA perror)) {
 	error_setup:
 		COSE_Encrypt_Free((HCOSE_ENCRYPT)pobj);
 		return NULL;
 	}

 	if (!cn_cbor_mapput_int(pobj->m_message.m_cbor, COSE_Header_Type, cn_cbor_int_create(1, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) {
 		if (perror != NULL) perror->err = COSE_ERR_OUT_OF_MEMORY;
 		goto error_setup;
 	}

 	return (HCOSE_ENCRYPT) pobj;
 }

 HCOSE_ENCRYPT _COSE_Encrypt_Init_From_Object(cn_cbor * cbor, COSE_Encrypt * pIn, CBOR_CONTEXT_COMMA cose_errback * perr)
 {
 	COSE_Encrypt * pobj = pIn;
 	cn_cbor * pRecipients = NULL;
 	cn_cbor * tmp;
 	cose_errback error = { 0 };
 	if (perr == NULL) perr = &error;

 	if (pobj == NULL) pobj = (COSE_Encrypt *)COSE_CALLOC(1, sizeof(COSE_Encrypt), context);
 	if (pobj == NULL) {
 		perr->err = COSE_ERR_OUT_OF_MEMORY;
 	errorReturn:
 		if ((pIn == NULL) && (pobj != NULL)) COSE_FREE(pobj, context);
 		return NULL;
 	}

 	if (!_COSE_Init_From_Object(&pobj->m_message, cbor, CBOR_CONTEXT_PARAM_COMMA perr)) {
 		goto errorReturn;
 	}

 	tmp = cn_cbor_mapget_int(cbor, COSE_Header_Ciphertext);
 	if (tmp != NULL) {
 		CHECK_CONDITION(tmp->type == CN_CBOR_BYTES, COSE_ERR_INVALID_PARAMETER);
 		pobj->cbContent = tmp->length;
 		pobj->pbContent = tmp->v.str;
 	}

 	pRecipients = (cn_cbor *) cn_cbor_mapget_int(cbor, COSE_Header_Recipients);
 	if (pRecipients != NULL) {
 		CHECK_CONDITION(pRecipients->type == CN_CBOR_ARRAY, COSE_ERR_INVALID_PARAMETER);

 		pRecipients = pRecipients->first_child;
 		while (pRecipients != NULL) {
 			COSE_RecipientInfo * pInfo = _COSE_Recipient_Init_From_Object(pRecipients, CBOR_CONTEXT_PARAM_COMMA perr);
 			CHECK_CONDITION(pInfo != NULL, COSE_ERR_OUT_OF_MEMORY);

 			pInfo->m_recipientNext = pobj->m_recipientFirst;
 			pobj->m_recipientFirst = pInfo;
 			pRecipients = pRecipients->next;
 		}
 	}

 	return(HCOSE_ENCRYPT) pobj;
 }

 bool COSE_Encrypt_Free(HCOSE_ENCRYPT h)
 {
 #ifdef USE_CBOR_CONTEXT
 	cn_cbor_context context;
 #endif

 	if (!IsValidEncryptHandle(h)) return false;

 #ifdef USE_CBOR_CONTEXT
 	context = ((COSE_Encrypt *)h)->m_message.m_allocContext;
 #endif

 	_COSE_Encrypt_Release((COSE_Encrypt *)h);

 	COSE_FREE((COSE_Encrypt *)h, &context);

 	return true;
 }

 void _COSE_Encrypt_Release(COSE_Encrypt * p)
 {
 	if (p->pbContent != NULL) COSE_FREE(p->pbContent, &p->m_message.m_allocContext);
 	//	if (p->pbIV != NULL) COSE_FREE(p->pbIV, &p->m_message.m_allocContext);
 	if (p->pbKey != NULL) COSE_FREE(p ->pbKey, &p->m_message.m_allocContext);

 	_COSE_Release(&p->m_message);
 }

 HCOSE_RECIPIENT COSE_Encrypt_add_shared_secret(HCOSE_ENCRYPT hcose, COSE_Algorithms alg, byte * rgbKey, int cbKey, byte * rgbKid, int cbKid, cose_errback * perror)
 {
 #ifdef USE_CBOR_CONTEXT
 	cn_cbor_context * context;
 #endif // USE_CBOR_CONTEXT
 	COSE_RecipientInfo * pobj;
 	COSE_Encrypt * pcose = (COSE_Encrypt *)hcose;

 	if (!IsValidEncryptHandle(hcose) || (rgbKey == NULL)) {
 		if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
 		return NULL;
 	}

 	switch (alg) {
 	case COSE_Algorithm_Direct:
 		break;

 	default:
 		if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
 		return NULL;
 	}


 #ifdef USE_CBOR_CONTEXT
 	context = &pcose->m_message.m_allocContext;
 #endif // USE_CBOR_CONTEXT

 	pobj = (COSE_RecipientInfo *) COSE_CALLOC(1, sizeof(COSE_RecipientInfo) , context);
 	if (pobj == NULL) {
 		oom_error:
 		if (perror != NULL) perror->err = COSE_ERR_OUT_OF_MEMORY;
 	error:
 		// M00BUG COSE_Recipient_Free(pobj);
 		return NULL;
 	}

 	if (!_COSE_Init(&pobj->m_encrypt.m_message, CBOR_CONTEXT_PARAM_COMMA perror)) {
 		goto error;
 	}

 	if (!cn_cbor_mapput_int(pobj->m_encrypt.m_message.m_unprotectMap, COSE_Header_Algorithm, cn_cbor_int_create(alg, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) goto error;

 	if (cbKid > 0) {
 		byte * pb = (byte *)COSE_CALLOC(cbKid, 1, context);
 		if (pb == NULL) goto oom_error;
 		memcpy(pb, rgbKid, cbKid);
 		if (!cn_cbor_mapput_int(pobj->m_encrypt.m_message.m_unprotectMap, COSE_Header_KID, cn_cbor_data_create(pb, cbKid, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) {
 			COSE_FREE(pb, context);
 			goto oom_error; // M00BUG - get error from CBOR
 		}
 	}


 	pobj->m_encrypt.pbKey = (byte *) COSE_CALLOC(cbKey, 1, context);
 	if (pobj->m_encrypt.pbKey == NULL) goto error;
 	memcpy(pobj->m_encrypt.pbKey, rgbKey, cbKey);
 	pobj->m_encrypt.cbKey = cbKey;

 	pobj->m_recipientNext = pcose->m_recipientFirst;
 	pcose->m_recipientFirst = pobj;

 	cn_cbor * pRecipients = (cn_cbor *) cn_cbor_mapget_int(pcose->m_message.m_cbor, COSE_Header_Recipients);
 	if (pRecipients == NULL) {
 		pRecipients = cn_cbor_array_create(CBOR_CONTEXT_PARAM_COMMA NULL);
 		if (pRecipients == NULL) goto error;
 		if (!cn_cbor_mapput_int(pcose->m_message.m_cbor, COSE_Header_Recipients, pRecipients, CBOR_CONTEXT_PARAM_COMMA NULL)) {
 			cn_cbor_free(pRecipients, context);
 			goto error;
 		}
 	}

 	cn_cbor_array_append(pRecipients, pobj->m_encrypt.m_message.m_cbor, NULL);

 	pobj->m_encrypt.m_message.m_flags |= 1;
 	return (HCOSE_RECIPIENT) pobj;
 }

 bool COSE_Encrypt_decrypt(HCOSE_ENCRYPT h, HCOSE_RECIPIENT hRecip, cose_errback * perr)
 {
 	COSE_Encrypt * pcose = (COSE_Encrypt *)h;
 	COSE_RecipientInfo * pRecip = (COSE_RecipientInfo *)hRecip;
 	cose_errback error = { 0 };
 	bool f;

 	if (!IsValidEncryptHandle(h) || (!IsValidRecipientHandle(hRecip))) {
 		if (perr != NULL) perr->err = COSE_ERR_INVALID_PARAMETER;
 		return false;
 	}

 	f = _COSE_Encrypt_decrypt(pcose, pRecip, 0, NULL, &error);
 	if (perr != NULL) *perr = error;
 	return f;
 }

 bool _COSE_Encrypt_decrypt(COSE_Encrypt * pcose, COSE_RecipientInfo * pRecip, int cbitKey, byte *pbKeyIn, cose_errback * perr)
 {
 	int alg;
 	const cn_cbor * cn = NULL;

 	byte * pbKey = pbKeyIn;
 	cn_cbor_context * context;
 	byte * pbAuthData = NULL;
 	ssize_t cbAuthData;
 	cn_cbor * pAuthData = NULL;
 	byte * pbProtected = NULL;
 	ssize_t cbProtected;
 	cn_cbor * ptmp = NULL;

 	assert(perr != NULL);

 #ifdef USE_CBOR_CONTEXT
 	context = &pcose->m_message.m_allocContext;
 #endif

 	cn = _COSE_map_get_int(&pcose->m_message, COSE_Header_Algorithm, COSE_BOTH, perr);
 	if (cn == NULL) {
 	error:
 	errorReturn:
 		if (pbProtected != NULL) COSE_FREE(pbProtected, context);
 		if (pbAuthData != NULL) COSE_FREE(pbAuthData, context);
 		if (pAuthData != NULL) cn_cbor_free(pAuthData CBOR_CONTEXT_PARAM);
 		if ((pbKey != NULL) && (pbKeyIn == NULL)) {
 			memset(pbKey, 0xff, cbitKey / 8);
 			COSE_FREE(pbKey, context);
 		}
 		return false;
 	}
 	CHECK_CONDITION(cn->type == CN_CBOR_UINT, CN_CBOR_ERR_INVALID_PARAMETER);
 	alg = cn->v.uint;

 	switch (alg) {
 	case COSE_Algorithm_AES_CCM_16_64_128:
 	case COSE_Algorithm_AES_CCM_16_128_128:
 	case COSE_Algorithm_AES_CCM_64_64_128:
 	case COSE_Algorithm_AES_CCM_64_128_128:
 		cbitKey = 128;
 		break;

 	case COSE_Algorithm_Direct:
 		CHECK_CONDITION(pcose->cbKey == cbitKey / 8, COSE_ERR_INVALID_PARAMETER);
 		break;

 	default:
 		CHECK_CONDITION(false, COSE_ERR_UNKNOWN_ALGORITHM);
 		break;
 	}

 	//  Allocate the key if we have not already done so

 	if (pbKey == NULL) {
 		pbKey = COSE_CALLOC(cbitKey / 8, 1, context);
 		CHECK_CONDITION(pbKey != NULL, COSE_ERR_OUT_OF_MEMORY);
 	}

 	//  If there is a recipient - ask it for the key

 	for (pRecip = pcose->m_recipientFirst; pRecip != NULL; pRecip = pRecip->m_recipientNext) {
 		if (_COSE_Recipient_decrypt(pRecip, cbitKey, pbKey, perr)) break;
 	}

 	//  Build protected headers

 	if ((pcose->m_message.m_protectedMap != NULL) && (pcose->m_message.m_protectedMap->first_child != NULL)) {
 		cbProtected = cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), pcose->m_message.m_protectedMap);
 		pbProtected = (byte *)COSE_CALLOC(cbProtected, 1, context);
 		if (pbProtected == NULL) goto error;
 		if (cn_cbor_encoder_write(pbProtected, 0, cbProtected, pcose->m_message.m_protectedMap) != cbProtected) goto error;
 		if (!cn_cbor_mapput_int(pcose->m_message.m_cbor, COSE_Header_Protected, cn_cbor_data_create(pbProtected, cbProtected, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) goto error;
 	}
 	else {
 		pbProtected = NULL;
 		cbProtected = 0;
 	}

 	//  Build authenticated data
 	pbAuthData = NULL;
 	pAuthData = cn_cbor_array_create(CBOR_CONTEXT_PARAM_COMMA NULL);

 	ptmp = cn_cbor_data_create(pbProtected, cbProtected, CBOR_CONTEXT_PARAM_COMMA NULL);
 	CHECK_CONDITION(ptmp != NULL, COSE_ERR_CBOR);
 	cn_cbor_array_append(pAuthData, ptmp, NULL);
 	pbProtected = NULL;

 	ptmp = cn_cbor_data_create(NULL, 0, CBOR_CONTEXT_PARAM_COMMA NULL);
 	CHECK_CONDITION(ptmp != NULL, COSE_ERR_CBOR);
 	cn_cbor_array_append(pAuthData, ptmp, NULL);

 	cbAuthData = cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), pAuthData);
 	pbAuthData = (byte *)COSE_CALLOC(cbAuthData, 1, context);
 	CHECK_CONDITION(pbAuthData != NULL, COSE_ERR_OUT_OF_MEMORY);
 	CHECK_CONDITION((cn_cbor_encoder_write(pbAuthData, 0, cbAuthData, pAuthData) == cbAuthData), COSE_ERR_CBOR);

 	switch (alg) {
 	case COSE_Algorithm_AES_CCM_64_64_128:
 	case COSE_Algorithm_AES_CCM_64_64_256:
 		if (!AES_CCM_Decrypt(pcose, 8, 8, pbKey, cbitKey/8, pbAuthData, cbAuthData, perr)) {
 			goto error;
 		}
 		break;

 	case COSE_Algorithm_Direct:
 		CHECK_CONDITION((pcose->cbKey == cbitKey / 8),  COSE_ERR_INVALID_PARAMETER);
 		memcpy(pbKey, pcose->pbKey, pcose->cbKey);
 		break;

 	default:
 		CHECK_CONDITION(false, COSE_ERR_UNKNOWN_ALGORITHM);
 		break;
 	}

 	if (pbProtected != NULL) COSE_FREE(pbProtected, context);
 	if (pbAuthData != NULL) COSE_FREE(pbAuthData, context);
 	if (pAuthData != NULL) cn_cbor_free(pAuthData CBOR_CONTEXT_PARAM);
 	if ((pbKey != NULL) && (pbKeyIn == NULL)) COSE_FREE(pbKey, context);
 	perr->err = COSE_ERR_NONE;

 	return true;
 }

 bool COSE_Encrypt_encrypt(HCOSE_ENCRYPT h, cose_errback * perror)
 {
 	int alg;
 	int t;
 	COSE_RecipientInfo * pri;
 	const cn_cbor * cn_Alg = NULL;
 	byte * pbAuthData = NULL;
 	cn_cbor * pAuthData = NULL;
 	cn_cbor * ptmp = NULL;
 	byte * pbProtected = NULL;
 	ssize_t cbProtected = 0;
 	size_t cbitKey;
 	cn_cbor_context * context;
 	COSE_Encrypt * pcose = (COSE_Encrypt *) h;
 	cose_errback error;

 	if (!IsValidEncryptHandle(h)) {
 		if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
 		return false;
 	}
 #ifdef USE_CBOR_CONTEXT
 	context = &pcose->m_message.m_allocContext;
 #endif // USE_CBOR_CONTEXT

 	cn_Alg = _COSE_map_get_int(&pcose->m_message, COSE_Header_Algorithm, COSE_BOTH, &error);

 	if (cn_Alg == NULL) {
 	error:
 		if (pbProtected != NULL) COSE_FREE(pbProtected, context);
 		if (pbAuthData != NULL) COSE_FREE(pbAuthData, context);
 		if (pAuthData != NULL) cn_cbor_free(pAuthData CBOR_CONTEXT_PARAM);
 		if (ptmp != NULL) cn_cbor_free(ptmp CBOR_CONTEXT_PARAM);
 		if (perror != NULL) *perror = error;
 		return false;
 	}
 	if ((cn_Alg->type != CN_CBOR_UINT) && (cn_Alg->type != CN_CBOR_INT)) goto error;
 	alg = cn_Alg->v.uint;

 	//  Get the key size

 	switch (alg) {
 	case COSE_Algorithm_AES_CCM_64_64_128:
 	case COSE_Algorithm_AES_CCM_16_128_128:
 	case COSE_Algorithm_AES_CCM_64_128_128:
 	case COSE_Algorithm_AES_CCM_16_64_128:
 		cbitKey = 128;
 		break;

 	case COSE_Algorithm_Direct:
 		cbitKey = 0;
 		break;

 	default:
 		goto error;
 	}

 	//  If we are doing direct encryption - then recipient generates the key

 	if (pcose->pbKey == NULL) {
 		t = 0;
 		for (pri = pcose->m_recipientFirst; pri != NULL; pri = pri->m_recipientNext) {
 			if (pri->m_encrypt.m_message.m_flags & 1) {
 				t |= 1;
 				pcose->pbKey = _COSE_RecipientInfo_generateKey(pri, cbitKey);
 				if (pcose->pbKey == NULL) goto error;
 				pcose->cbKey = cbitKey / 8;
 			}
 			else {
 				t |= 2;
 			}
 		}
 		if (t == 3) {
 			error.err = CN_CBOR_ERR_INVALID_PARAMETER;
 			goto error;
 		}
 	}

 	if (pcose->pbKey == NULL) {
 		pcose->pbKey = (byte *) COSE_CALLOC(cbitKey/8, 1, context);
 		if (pcose->pbKey == NULL) goto error;
 		pcose->cbKey = cbitKey / 8;
 		rand_bytes(pcose->pbKey, pcose->cbKey);
 	}

 	//  Build protected headers

 	if (pcose->m_message.m_protectedMap->first_child != NULL) {
 		cbProtected = cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), pcose->m_message.m_protectedMap);
 		pbProtected = (byte *) COSE_CALLOC(cbProtected, 1, context);
 		if (pbProtected == NULL) goto error;
 		if (cn_cbor_encoder_write(pbProtected, 0, cbProtected, pcose->m_message.m_protectedMap) != cbProtected) goto error;
 		if (!cn_cbor_mapput_int(pcose->m_message.m_cbor, COSE_Header_Protected, cn_cbor_data_create(pbProtected, cbProtected, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) goto error;
 	}
 	else {
 		pbProtected = NULL;
 		cbProtected = 0;
 	}

 	//  Add Unprotected headers
 	if (pcose->m_message.m_unprotectMap->first_child != NULL) {
 		if (!cn_cbor_mapput_int(pcose->m_message.m_cbor, COSE_Header_Unprotected, pcose->m_message.m_unprotectMap, CBOR_CONTEXT_PARAM_COMMA NULL)) goto error;
 		pcose->m_message.m_ownUnprotectedMap = false;
 	}

 	//  Build authenticated data
 	ssize_t cbAuthData = 0;
 	pbAuthData = NULL;
 	pAuthData = cn_cbor_array_create(CBOR_CONTEXT_PARAM_COMMA NULL);

 	ptmp = cn_cbor_data_create(pbProtected, cbProtected, CBOR_CONTEXT_PARAM_COMMA NULL);
 	if (ptmp == NULL) goto error;
 	cn_cbor_array_append(pAuthData, ptmp, NULL);
 	pbProtected = NULL;
 	ptmp = NULL;

 	ptmp = cn_cbor_data_create(NULL, 0, CBOR_CONTEXT_PARAM_COMMA NULL);
 	if (ptmp == NULL) goto error;
 	cn_cbor_array_append(pAuthData, ptmp, NULL);
 	ptmp = NULL;

 	cbAuthData = cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), pAuthData);
 	pbAuthData = (byte *) COSE_CALLOC(cbAuthData, 1, context);
 	if (pbAuthData == NULL) goto error;
 	if (cn_cbor_encoder_write(pbAuthData, 0, cbAuthData, pAuthData) != cbAuthData) goto error;

 	switch (alg) {
 #ifdef INCLUDE_AES_CCM_64
 	case COSE_Algorithm_AES_CCM_64_128_128:
 		if (!AES_CCM_Encrypt(pcose, 64, 8, pbAuthData, cbAuthData, perror)) goto error;
 		break;
 #endif

 	case COSE_Algorithm_Direct:
 		break;

 	default:
 		return false;
 	}

 	for (pri = pcose->m_recipientFirst; pri != NULL; pri = pri->m_recipientNext) {
 		_COSE_Encrypt_SetContent(&pri->m_encrypt, pcose->pbKey, pcose->cbKey, &error);
 		if (error.err != COSE_ERR_NONE) goto error;

 		if (!COSE_Encrypt_encrypt((HCOSE_ENCRYPT) &pri->m_encrypt, &error)) goto error;
 	}

 	//  Figure out the clean up

 	if (pbAuthData != NULL) COSE_FREE(pbAuthData, context);
 	if (pAuthData != NULL) cn_cbor_free(pAuthData CBOR_CONTEXT_PARAM);

 	return true;
 }

 void COSE_Encrypt_SetContent(HCOSE_ENCRYPT h, const byte * rgb, size_t cb, cose_errback * perror)
 {
 	if (!IsValidEncryptHandle(h) || (rgb == NULL)) {
 		if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
 	}

 	_COSE_Encrypt_SetContent((COSE_Encrypt *)h, rgb, cb, perror);
 }

 void _COSE_Encrypt_SetContent(COSE_Encrypt * cose, const byte * rgb, size_t cb, cose_errback * perror)
 {
 	cose->pbContent = (byte *)COSE_CALLOC(cb, 1, &cose->m_message.m_allocContext);
 	if (cose->pbContent == NULL) {
 		if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
 		return;
 	}
 	memcpy(cose->pbContent, rgb, cb);
 	cose->cbContent = cb;

 	if (perror != NULL) perror->err = COSE_ERR_NONE;
 	return;
 }

 const cn_cbor * COSE_Encrypt_map_get_int(HCOSE_ENCRYPT h, int key, int flags, cose_errback * perror)
 {
 	if (!IsValidEncryptHandle(h)) {
 		if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
 		return NULL;
 	}

 	return _COSE_map_get_int(&((COSE_Encrypt *)h)->m_message, key, flags, perror);
 }


 bool COSE_Encrypt_map_put(HCOSE_ENCRYPT h, int key, cn_cbor * value, int flags, cose_errback * perror)
 {
 	if (!IsValidEncryptHandle(h) || (value == NULL)) {
 		if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
 		return false;
 	}

 	return _COSE_map_put(&((COSE_Encrypt *)h)->m_message, key, value, flags, perror);
 }
	#include <stdlib.h>
	#include <memory.h>
	#include <stdio.h>
	#include <assert.h>

	#include "cose.h"
	#include "cose_int.h"
	#include "configure.h"
	#include "crypto.h"

	byte RgbDontUse[8 * 1024]; // Remove this array when we can compute the size of a cbor serialization without this hack.


	bool IsValidEncryptHandle(HCOSE_ENCRYPT h)
	{
	COSE_Encrypt * p = (COSE_Encrypt *)h;
	if (p == NULL) return false;
	return true;
	}


	size_t COSE_Encode(HCOSE msg, byte * rgb, int ib, size_t cb)
	{
	if (rgb == NULL) return cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), ((COSE *)msg)->m_cbor) + ib;
	return cn_cbor_encoder_write(rgb, ib, cb, ((COSE*)msg)->m_cbor);
	}

	HCOSE_ENCRYPT COSE_Encrypt_Init(CBOR_CONTEXT_COMMA cose_errback * perror)
	{
	COSE_Encrypt * pobj = (COSE_Encrypt *)COSE_CALLOC(1, sizeof(COSE_Encrypt), context);
	if (pobj == NULL) {
	if (perror != NULL) perror->err = COSE_ERR_OUT_OF_MEMORY;
	return NULL;
	}

	if (!_COSE_Init(&pobj->m_message, CBOR_CONTEXT_PARAM_COMMA perror)) {
	error_setup:
	COSE_Encrypt_Free((HCOSE_ENCRYPT)pobj);
	return NULL;
	}

	if (!cn_cbor_mapput_int(pobj->m_message.m_cbor, COSE_Header_Type, cn_cbor_int_create(1, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) {
	if (perror != NULL) perror->err = COSE_ERR_OUT_OF_MEMORY;
	goto error_setup;
	}

	return (HCOSE_ENCRYPT) pobj;
	}

	HCOSE_ENCRYPT _COSE_Encrypt_Init_From_Object(cn_cbor * cbor, COSE_Encrypt * pIn, CBOR_CONTEXT_COMMA cose_errback * perr)
	{
	COSE_Encrypt * pobj = pIn;
	cn_cbor * pRecipients = NULL;
	cn_cbor * tmp;
	cose_errback error = { 0 };
	if (perr == NULL) perr = &error;

	if (pobj == NULL) pobj = (COSE_Encrypt *)COSE_CALLOC(1, sizeof(COSE_Encrypt), context);
	if (pobj == NULL) {
	perr->err = COSE_ERR_OUT_OF_MEMORY;
	errorReturn:
	if ((pIn == NULL) && (pobj != NULL)) COSE_FREE(pobj, context);
	return NULL;
	}

	if (!_COSE_Init_From_Object(&pobj->m_message, cbor, CBOR_CONTEXT_PARAM_COMMA perr)) {
	goto errorReturn;
	}

	tmp = cn_cbor_mapget_int(cbor, COSE_Header_Ciphertext);
	if (tmp != NULL) {
	CHECK_CONDITION(tmp->type == CN_CBOR_BYTES, COSE_ERR_INVALID_PARAMETER);
	pobj->cbContent = tmp->length;
	pobj->pbContent = tmp->v.str;
	}

	pRecipients = (cn_cbor *) cn_cbor_mapget_int(cbor, COSE_Header_Recipients);
	if (pRecipients != NULL) {
	CHECK_CONDITION(pRecipients->type == CN_CBOR_ARRAY, COSE_ERR_INVALID_PARAMETER);

	pRecipients = pRecipients->first_child;
	while (pRecipients != NULL) {
	COSE_RecipientInfo * pInfo = _COSE_Recipient_Init_From_Object(pRecipients, CBOR_CONTEXT_PARAM_COMMA perr);
	CHECK_CONDITION(pInfo != NULL, COSE_ERR_OUT_OF_MEMORY);

	pInfo->m_recipientNext = pobj->m_recipientFirst;
	pobj->m_recipientFirst = pInfo;
	pRecipients = pRecipients->next;
	}
	}

	return(HCOSE_ENCRYPT) pobj;
	}

	bool COSE_Encrypt_Free(HCOSE_ENCRYPT h)
	{
	#ifdef USE_CBOR_CONTEXT
	cn_cbor_context context;
	#endif

	if (!IsValidEncryptHandle(h)) return false;

	#ifdef USE_CBOR_CONTEXT
	context = ((COSE_Encrypt *)h)->m_message.m_allocContext;
	#endif

	_COSE_Encrypt_Release((COSE_Encrypt *)h);

	COSE_FREE((COSE_Encrypt *)h, &context);

	return true;
	}

	void _COSE_Encrypt_Release(COSE_Encrypt * p)
	{
	if (p->pbContent != NULL) COSE_FREE(p->pbContent, &p->m_message.m_allocContext);
	// if (p->pbIV != NULL) COSE_FREE(p->pbIV, &p->m_message.m_allocContext);
	if (p->pbKey != NULL) COSE_FREE(p ->pbKey, &p->m_message.m_allocContext);

	_COSE_Release(&p->m_message);
	}

	HCOSE_RECIPIENT COSE_Encrypt_add_shared_secret(HCOSE_ENCRYPT hcose, COSE_Algorithms alg, byte * rgbKey, int cbKey, byte * rgbKid, int cbKid, cose_errback * perror)
	{
	#ifdef USE_CBOR_CONTEXT
	cn_cbor_context * context;
	#endif // USE_CBOR_CONTEXT
	COSE_RecipientInfo * pobj;
	COSE_Encrypt * pcose = (COSE_Encrypt *)hcose;

	if (!IsValidEncryptHandle(hcose) \|\| (rgbKey == NULL)) {
	if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
	return NULL;
	}

	switch (alg) {
	case COSE_Algorithm_Direct:
	break;

	default:
	if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
	return NULL;
	}


	#ifdef USE_CBOR_CONTEXT
	context = &pcose->m_message.m_allocContext;
	#endif // USE_CBOR_CONTEXT

	pobj = (COSE_RecipientInfo *) COSE_CALLOC(1, sizeof(COSE_RecipientInfo) , context);
	if (pobj == NULL) {
	oom_error:
	if (perror != NULL) perror->err = COSE_ERR_OUT_OF_MEMORY;
	error:
	// M00BUG COSE_Recipient_Free(pobj);
	return NULL;
	}

	if (!_COSE_Init(&pobj->m_encrypt.m_message, CBOR_CONTEXT_PARAM_COMMA perror)) {
	goto error;
	}

	if (!cn_cbor_mapput_int(pobj->m_encrypt.m_message.m_unprotectMap, COSE_Header_Algorithm, cn_cbor_int_create(alg, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) goto error;

	if (cbKid > 0) {
	byte * pb = (byte *)COSE_CALLOC(cbKid, 1, context);
	if (pb == NULL) goto oom_error;
	memcpy(pb, rgbKid, cbKid);
	if (!cn_cbor_mapput_int(pobj->m_encrypt.m_message.m_unprotectMap, COSE_Header_KID, cn_cbor_data_create(pb, cbKid, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) {
	COSE_FREE(pb, context);
	goto oom_error; // M00BUG - get error from CBOR
	}
	}


	pobj->m_encrypt.pbKey = (byte *) COSE_CALLOC(cbKey, 1, context);
	if (pobj->m_encrypt.pbKey == NULL) goto error;
	memcpy(pobj->m_encrypt.pbKey, rgbKey, cbKey);
	pobj->m_encrypt.cbKey = cbKey;

	pobj->m_recipientNext = pcose->m_recipientFirst;
	pcose->m_recipientFirst = pobj;

	cn_cbor * pRecipients = (cn_cbor *) cn_cbor_mapget_int(pcose->m_message.m_cbor, COSE_Header_Recipients);
	if (pRecipients == NULL) {
	pRecipients = cn_cbor_array_create(CBOR_CONTEXT_PARAM_COMMA NULL);
	if (pRecipients == NULL) goto error;
	if (!cn_cbor_mapput_int(pcose->m_message.m_cbor, COSE_Header_Recipients, pRecipients, CBOR_CONTEXT_PARAM_COMMA NULL)) {
	cn_cbor_free(pRecipients, context);
	goto error;
	}
	}

	cn_cbor_array_append(pRecipients, pobj->m_encrypt.m_message.m_cbor, NULL);

	pobj->m_encrypt.m_message.m_flags \|= 1;
	return (HCOSE_RECIPIENT) pobj;
	}

	bool COSE_Encrypt_decrypt(HCOSE_ENCRYPT h, HCOSE_RECIPIENT hRecip, cose_errback * perr)
	{
	COSE_Encrypt * pcose = (COSE_Encrypt *)h;
	COSE_RecipientInfo * pRecip = (COSE_RecipientInfo *)hRecip;
	cose_errback error = { 0 };
	bool f;

	if (!IsValidEncryptHandle(h) \|\| (!IsValidRecipientHandle(hRecip))) {
	if (perr != NULL) perr->err = COSE_ERR_INVALID_PARAMETER;
	return false;
	}

	f = _COSE_Encrypt_decrypt(pcose, pRecip, 0, NULL, &error);
	if (perr != NULL) *perr = error;
	return f;
	}

	bool _COSE_Encrypt_decrypt(COSE_Encrypt * pcose, COSE_RecipientInfo * pRecip, int cbitKey, byte pbKeyIn, cose_errback perr)
	{
	int alg;
	const cn_cbor * cn = NULL;

	byte * pbKey = pbKeyIn;
	cn_cbor_context * context;
	byte * pbAuthData = NULL;
	ssize_t cbAuthData;
	cn_cbor * pAuthData = NULL;
	byte * pbProtected = NULL;
	ssize_t cbProtected;
	cn_cbor * ptmp = NULL;

	assert(perr != NULL);

	#ifdef USE_CBOR_CONTEXT
	context = &pcose->m_message.m_allocContext;
	#endif

	cn = _COSE_map_get_int(&pcose->m_message, COSE_Header_Algorithm, COSE_BOTH, perr);
	if (cn == NULL) {
	error:
	errorReturn:
	if (pbProtected != NULL) COSE_FREE(pbProtected, context);
	if (pbAuthData != NULL) COSE_FREE(pbAuthData, context);
	if (pAuthData != NULL) cn_cbor_free(pAuthData CBOR_CONTEXT_PARAM);
	if ((pbKey != NULL) && (pbKeyIn == NULL)) {
	memset(pbKey, 0xff, cbitKey / 8);
	COSE_FREE(pbKey, context);
	}
	return false;
	}
	CHECK_CONDITION(cn->type == CN_CBOR_UINT, CN_CBOR_ERR_INVALID_PARAMETER);
	alg = cn->v.uint;

	switch (alg) {
	case COSE_Algorithm_AES_CCM_16_64_128:
	case COSE_Algorithm_AES_CCM_16_128_128:
	case COSE_Algorithm_AES_CCM_64_64_128:
	case COSE_Algorithm_AES_CCM_64_128_128:
	cbitKey = 128;
	break;

	case COSE_Algorithm_Direct:
	CHECK_CONDITION(pcose->cbKey == cbitKey / 8, COSE_ERR_INVALID_PARAMETER);
	break;

	default:
	CHECK_CONDITION(false, COSE_ERR_UNKNOWN_ALGORITHM);
	break;
	}

	// Allocate the key if we have not already done so

	if (pbKey == NULL) {
	pbKey = COSE_CALLOC(cbitKey / 8, 1, context);
	CHECK_CONDITION(pbKey != NULL, COSE_ERR_OUT_OF_MEMORY);
	}

	// If there is a recipient - ask it for the key

	for (pRecip = pcose->m_recipientFirst; pRecip != NULL; pRecip = pRecip->m_recipientNext) {
	if (_COSE_Recipient_decrypt(pRecip, cbitKey, pbKey, perr)) break;
	}

	// Build protected headers

	if ((pcose->m_message.m_protectedMap != NULL) && (pcose->m_message.m_protectedMap->first_child != NULL)) {
	cbProtected = cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), pcose->m_message.m_protectedMap);
	pbProtected = (byte *)COSE_CALLOC(cbProtected, 1, context);
	if (pbProtected == NULL) goto error;
	if (cn_cbor_encoder_write(pbProtected, 0, cbProtected, pcose->m_message.m_protectedMap) != cbProtected) goto error;
	if (!cn_cbor_mapput_int(pcose->m_message.m_cbor, COSE_Header_Protected, cn_cbor_data_create(pbProtected, cbProtected, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) goto error;
	}
	else {
	pbProtected = NULL;
	cbProtected = 0;
	}

	// Build authenticated data
	pbAuthData = NULL;
	pAuthData = cn_cbor_array_create(CBOR_CONTEXT_PARAM_COMMA NULL);

	ptmp = cn_cbor_data_create(pbProtected, cbProtected, CBOR_CONTEXT_PARAM_COMMA NULL);
	CHECK_CONDITION(ptmp != NULL, COSE_ERR_CBOR);
	cn_cbor_array_append(pAuthData, ptmp, NULL);
	pbProtected = NULL;

	ptmp = cn_cbor_data_create(NULL, 0, CBOR_CONTEXT_PARAM_COMMA NULL);
	CHECK_CONDITION(ptmp != NULL, COSE_ERR_CBOR);
	cn_cbor_array_append(pAuthData, ptmp, NULL);

	cbAuthData = cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), pAuthData);
	pbAuthData = (byte *)COSE_CALLOC(cbAuthData, 1, context);
	CHECK_CONDITION(pbAuthData != NULL, COSE_ERR_OUT_OF_MEMORY);
	CHECK_CONDITION((cn_cbor_encoder_write(pbAuthData, 0, cbAuthData, pAuthData) == cbAuthData), COSE_ERR_CBOR);

	switch (alg) {
	case COSE_Algorithm_AES_CCM_64_64_128:
	case COSE_Algorithm_AES_CCM_64_64_256:
	if (!AES_CCM_Decrypt(pcose, 8, 8, pbKey, cbitKey/8, pbAuthData, cbAuthData, perr)) {
	goto error;
	}
	break;

	case COSE_Algorithm_Direct:
	CHECK_CONDITION((pcose->cbKey == cbitKey / 8), COSE_ERR_INVALID_PARAMETER);
	memcpy(pbKey, pcose->pbKey, pcose->cbKey);
	break;

	default:
	CHECK_CONDITION(false, COSE_ERR_UNKNOWN_ALGORITHM);
	break;
	}

	if (pbProtected != NULL) COSE_FREE(pbProtected, context);
	if (pbAuthData != NULL) COSE_FREE(pbAuthData, context);
	if (pAuthData != NULL) cn_cbor_free(pAuthData CBOR_CONTEXT_PARAM);
	if ((pbKey != NULL) && (pbKeyIn == NULL)) COSE_FREE(pbKey, context);
	perr->err = COSE_ERR_NONE;

	return true;
	}

	bool COSE_Encrypt_encrypt(HCOSE_ENCRYPT h, cose_errback * perror)
	{
	int alg;
	int t;
	COSE_RecipientInfo * pri;
	const cn_cbor * cn_Alg = NULL;
	byte * pbAuthData = NULL;
	cn_cbor * pAuthData = NULL;
	cn_cbor * ptmp = NULL;
	byte * pbProtected = NULL;
	ssize_t cbProtected = 0;
	size_t cbitKey;
	cn_cbor_context * context;
	COSE_Encrypt * pcose = (COSE_Encrypt *) h;
	cose_errback error;

	if (!IsValidEncryptHandle(h)) {
	if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
	return false;
	}
	#ifdef USE_CBOR_CONTEXT
	context = &pcose->m_message.m_allocContext;
	#endif // USE_CBOR_CONTEXT

	cn_Alg = _COSE_map_get_int(&pcose->m_message, COSE_Header_Algorithm, COSE_BOTH, &error);

	if (cn_Alg == NULL) {
	error:
	if (pbProtected != NULL) COSE_FREE(pbProtected, context);
	if (pbAuthData != NULL) COSE_FREE(pbAuthData, context);
	if (pAuthData != NULL) cn_cbor_free(pAuthData CBOR_CONTEXT_PARAM);
	if (ptmp != NULL) cn_cbor_free(ptmp CBOR_CONTEXT_PARAM);
	if (perror != NULL) *perror = error;
	return false;
	}
	if ((cn_Alg->type != CN_CBOR_UINT) && (cn_Alg->type != CN_CBOR_INT)) goto error;
	alg = cn_Alg->v.uint;

	// Get the key size

	switch (alg) {
	case COSE_Algorithm_AES_CCM_64_64_128:
	case COSE_Algorithm_AES_CCM_16_128_128:
	case COSE_Algorithm_AES_CCM_64_128_128:
	case COSE_Algorithm_AES_CCM_16_64_128:
	cbitKey = 128;
	break;

	case COSE_Algorithm_Direct:
	cbitKey = 0;
	break;

	default:
	goto error;
	}

	// If we are doing direct encryption - then recipient generates the key

	if (pcose->pbKey == NULL) {
	t = 0;
	for (pri = pcose->m_recipientFirst; pri != NULL; pri = pri->m_recipientNext) {
	if (pri->m_encrypt.m_message.m_flags & 1) {
	t \|= 1;
	pcose->pbKey = _COSE_RecipientInfo_generateKey(pri, cbitKey);
	if (pcose->pbKey == NULL) goto error;
	pcose->cbKey = cbitKey / 8;
	}
	else {
	t \|= 2;
	}
	}
	if (t == 3) {
	error.err = CN_CBOR_ERR_INVALID_PARAMETER;
	goto error;
	}
	}

	if (pcose->pbKey == NULL) {
	pcose->pbKey = (byte *) COSE_CALLOC(cbitKey/8, 1, context);
	if (pcose->pbKey == NULL) goto error;
	pcose->cbKey = cbitKey / 8;
	rand_bytes(pcose->pbKey, pcose->cbKey);
	}

	// Build protected headers

	if (pcose->m_message.m_protectedMap->first_child != NULL) {
	cbProtected = cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), pcose->m_message.m_protectedMap);
	pbProtected = (byte *) COSE_CALLOC(cbProtected, 1, context);
	if (pbProtected == NULL) goto error;
	if (cn_cbor_encoder_write(pbProtected, 0, cbProtected, pcose->m_message.m_protectedMap) != cbProtected) goto error;
	if (!cn_cbor_mapput_int(pcose->m_message.m_cbor, COSE_Header_Protected, cn_cbor_data_create(pbProtected, cbProtected, CBOR_CONTEXT_PARAM_COMMA NULL), CBOR_CONTEXT_PARAM_COMMA NULL)) goto error;
	}
	else {
	pbProtected = NULL;
	cbProtected = 0;
	}

	// Add Unprotected headers
	if (pcose->m_message.m_unprotectMap->first_child != NULL) {
	if (!cn_cbor_mapput_int(pcose->m_message.m_cbor, COSE_Header_Unprotected, pcose->m_message.m_unprotectMap, CBOR_CONTEXT_PARAM_COMMA NULL)) goto error;
	pcose->m_message.m_ownUnprotectedMap = false;
	}

	// Build authenticated data
	ssize_t cbAuthData = 0;
	pbAuthData = NULL;
	pAuthData = cn_cbor_array_create(CBOR_CONTEXT_PARAM_COMMA NULL);

	ptmp = cn_cbor_data_create(pbProtected, cbProtected, CBOR_CONTEXT_PARAM_COMMA NULL);
	if (ptmp == NULL) goto error;
	cn_cbor_array_append(pAuthData, ptmp, NULL);
	pbProtected = NULL;
	ptmp = NULL;

	ptmp = cn_cbor_data_create(NULL, 0, CBOR_CONTEXT_PARAM_COMMA NULL);
	if (ptmp == NULL) goto error;
	cn_cbor_array_append(pAuthData, ptmp, NULL);
	ptmp = NULL;

	cbAuthData = cn_cbor_encoder_write(RgbDontUse, 0, sizeof(RgbDontUse), pAuthData);
	pbAuthData = (byte *) COSE_CALLOC(cbAuthData, 1, context);
	if (pbAuthData == NULL) goto error;
	if (cn_cbor_encoder_write(pbAuthData, 0, cbAuthData, pAuthData) != cbAuthData) goto error;

	switch (alg) {
	#ifdef INCLUDE_AES_CCM_64
	case COSE_Algorithm_AES_CCM_64_128_128:
	if (!AES_CCM_Encrypt(pcose, 64, 8, pbAuthData, cbAuthData, perror)) goto error;
	break;
	#endif

	case COSE_Algorithm_Direct:
	break;

	default:
	return false;
	}

	for (pri = pcose->m_recipientFirst; pri != NULL; pri = pri->m_recipientNext) {
	_COSE_Encrypt_SetContent(&pri->m_encrypt, pcose->pbKey, pcose->cbKey, &error);
	if (error.err != COSE_ERR_NONE) goto error;

	if (!COSE_Encrypt_encrypt((HCOSE_ENCRYPT) &pri->m_encrypt, &error)) goto error;
	}

	// Figure out the clean up

	if (pbAuthData != NULL) COSE_FREE(pbAuthData, context);
	if (pAuthData != NULL) cn_cbor_free(pAuthData CBOR_CONTEXT_PARAM);

	return true;
	}

	void COSE_Encrypt_SetContent(HCOSE_ENCRYPT h, const byte * rgb, size_t cb, cose_errback * perror)
	{
	if (!IsValidEncryptHandle(h) \|\| (rgb == NULL)) {
	if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
	}

	_COSE_Encrypt_SetContent((COSE_Encrypt *)h, rgb, cb, perror);
	}

	void _COSE_Encrypt_SetContent(COSE_Encrypt * cose, const byte * rgb, size_t cb, cose_errback * perror)
	{
	cose->pbContent = (byte *)COSE_CALLOC(cb, 1, &cose->m_message.m_allocContext);
	if (cose->pbContent == NULL) {
	if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
	return;
	}
	memcpy(cose->pbContent, rgb, cb);
	cose->cbContent = cb;

	if (perror != NULL) perror->err = COSE_ERR_NONE;
	return;
	}

	const cn_cbor * COSE_Encrypt_map_get_int(HCOSE_ENCRYPT h, int key, int flags, cose_errback * perror)
	{
	if (!IsValidEncryptHandle(h)) {
	if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
	return NULL;
	}

	return _COSE_map_get_int(&((COSE_Encrypt *)h)->m_message, key, flags, perror);
	}


	bool COSE_Encrypt_map_put(HCOSE_ENCRYPT h, int key, cn_cbor * value, int flags, cose_errback * perror)
	{
	if (!IsValidEncryptHandle(h) \|\| (value == NULL)) {
	if (perror != NULL) perror->err = COSE_ERR_INVALID_PARAMETER;
	return false;
	}

	return _COSE_map_put(&((COSE_Encrypt *)h)->m_message, key, value, flags, perror);
	}