Files
wolfssl/wolfcrypt/src/pkcs7.c
toddouska ce94243a20 Merge pull request #746 from cconlon/pkcs7ukm
PKCS7: fix optional UserKeyingMaterial encoding
2017-02-21 13:22:31 -08:00

3764 lines
116 KiB
C

/* pkcs7.c
*
* Copyright (C) 2006-2016 wolfSSL Inc.
*
* This file is part of wolfSSL.
*
* wolfSSL is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* wolfSSL is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <wolfssl/wolfcrypt/settings.h>
#ifdef HAVE_PKCS7
#include <wolfssl/wolfcrypt/pkcs7.h>
#include <wolfssl/wolfcrypt/error-crypt.h>
#include <wolfssl/wolfcrypt/logging.h>
#ifdef NO_INLINE
#include <wolfssl/wolfcrypt/misc.h>
#else
#define WOLFSSL_MISC_INCLUDED
#include <wolfcrypt/src/misc.c>
#endif
/* direction for processing, encoding or decoding */
typedef enum {
WC_PKCS7_ENCODE,
WC_PKCS7_DECODE
} pkcs7Direction;
/* placed ASN.1 contentType OID into *output, return idx on success,
* 0 upon failure */
static int wc_SetContentType(int pkcs7TypeOID, byte* output)
{
/* PKCS#7 content types, RFC 2315, section 14 */
const byte pkcs7[] = { 0x2A, 0x86, 0x48, 0x86, 0xF7,
0x0D, 0x01, 0x07 };
const byte data[] = { 0x2A, 0x86, 0x48, 0x86, 0xF7,
0x0D, 0x01, 0x07, 0x01 };
const byte signedData[] = { 0x2A, 0x86, 0x48, 0x86, 0xF7,
0x0D, 0x01, 0x07, 0x02};
const byte envelopedData[] = { 0x2A, 0x86, 0x48, 0x86, 0xF7,
0x0D, 0x01, 0x07, 0x03 };
const byte signedAndEnveloped[] = { 0x2A, 0x86, 0x48, 0x86, 0xF7,
0x0D, 0x01, 0x07, 0x04 };
const byte digestedData[] = { 0x2A, 0x86, 0x48, 0x86, 0xF7,
0x0D, 0x01, 0x07, 0x05 };
const byte encryptedData[] = { 0x2A, 0x86, 0x48, 0x86, 0xF7,
0x0D, 0x01, 0x07, 0x06 };
int idSz;
int typeSz = 0, idx = 0;
const byte* typeName = 0;
byte ID_Length[MAX_LENGTH_SZ];
switch (pkcs7TypeOID) {
case PKCS7_MSG:
typeSz = sizeof(pkcs7);
typeName = pkcs7;
break;
case DATA:
typeSz = sizeof(data);
typeName = data;
break;
case SIGNED_DATA:
typeSz = sizeof(signedData);
typeName = signedData;
break;
case ENVELOPED_DATA:
typeSz = sizeof(envelopedData);
typeName = envelopedData;
break;
case SIGNED_AND_ENVELOPED_DATA:
typeSz = sizeof(signedAndEnveloped);
typeName = signedAndEnveloped;
break;
case DIGESTED_DATA:
typeSz = sizeof(digestedData);
typeName = digestedData;
break;
case ENCRYPTED_DATA:
typeSz = sizeof(encryptedData);
typeName = encryptedData;
break;
default:
WOLFSSL_MSG("Unknown PKCS#7 Type");
return 0;
};
idSz = SetLength(typeSz, ID_Length);
output[idx++] = ASN_OBJECT_ID;
XMEMCPY(output + idx, ID_Length, idSz);
idx += idSz;
XMEMCPY(output + idx, typeName, typeSz);
idx += typeSz;
return idx;
}
/* get ASN.1 contentType OID sum, return 0 on success, <0 on failure */
static int wc_GetContentType(const byte* input, word32* inOutIdx, word32* oid,
word32 maxIdx)
{
WOLFSSL_ENTER("wc_GetContentType");
if (GetObjectId(input, inOutIdx, oid, oidIgnoreType, maxIdx) < 0)
return ASN_PARSE_E;
return 0;
}
/* return block size for algorithm represented by oid, or <0 on error */
static int wc_PKCS7_GetOIDBlockSize(int oid)
{
int blockSz;
switch (oid) {
#ifndef NO_AES
case AES128CBCb:
case AES192CBCb:
case AES256CBCb:
blockSz = AES_BLOCK_SIZE;
break;
#endif
#ifndef NO_DES3
case DESb:
case DES3b:
blockSz = DES_BLOCK_SIZE;
break;
#endif
default:
WOLFSSL_MSG("Unsupported content cipher type");
return ALGO_ID_E;
};
return blockSz;
}
/* get key size for algorithm represented by oid, or <0 on error */
static int wc_PKCS7_GetOIDKeySize(int oid)
{
int blockKeySz;
switch (oid) {
#ifndef NO_AES
case AES128CBCb:
case AES128_WRAP:
blockKeySz = 16;
break;
case AES192CBCb:
case AES192_WRAP:
blockKeySz = 24;
break;
case AES256CBCb:
case AES256_WRAP:
blockKeySz = 32;
break;
#endif
#ifndef NO_DES3
case DESb:
blockKeySz = DES_KEYLEN;
break;
case DES3b:
blockKeySz = DES3_KEYLEN;
break;
#endif
default:
WOLFSSL_MSG("Unsupported content cipher type");
return ALGO_ID_E;
};
return blockKeySz;
}
/* init PKCS7 struct with recipient cert, decode into DecodedCert */
int wc_PKCS7_InitWithCert(PKCS7* pkcs7, byte* cert, word32 certSz)
{
int ret = 0;
XMEMSET(pkcs7, 0, sizeof(PKCS7));
/* default heap hint is null or test value */
#ifdef WOLFSSL_HEAP_TEST
pkcs7->heap = (void*)WOLFSSL_HEAP_TEST;
#else
pkcs7->heap = NULL;
#endif
if (cert != NULL && certSz > 0) {
#ifdef WOLFSSL_SMALL_STACK
DecodedCert* dCert;
dCert = (DecodedCert*)XMALLOC(sizeof(DecodedCert), NULL,
DYNAMIC_TYPE_PKCS7);
if (dCert == NULL)
return MEMORY_E;
#else
DecodedCert stack_dCert;
DecodedCert* dCert = &stack_dCert;
#endif
pkcs7->singleCert = cert;
pkcs7->singleCertSz = certSz;
InitDecodedCert(dCert, cert, certSz, pkcs7->heap);
ret = ParseCert(dCert, CA_TYPE, NO_VERIFY, 0);
if (ret < 0) {
FreeDecodedCert(dCert);
#ifdef WOLFSSL_SMALL_STACK
XFREE(dCert, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ret;
}
XMEMCPY(pkcs7->publicKey, dCert->publicKey, dCert->pubKeySize);
pkcs7->publicKeySz = dCert->pubKeySize;
pkcs7->publicKeyOID = dCert->keyOID;
XMEMCPY(pkcs7->issuerHash, dCert->issuerHash, KEYID_SIZE);
pkcs7->issuer = dCert->issuerRaw;
pkcs7->issuerSz = dCert->issuerRawLen;
XMEMCPY(pkcs7->issuerSn, dCert->serial, dCert->serialSz);
pkcs7->issuerSnSz = dCert->serialSz;
FreeDecodedCert(dCert);
#ifdef WOLFSSL_SMALL_STACK
XFREE(dCert, NULL, DYNAMIC_TYPE_PKCS7);
#endif
}
return ret;
}
/* free linked list of PKCS7DecodedAttrib structs */
static void wc_PKCS7_FreeDecodedAttrib(PKCS7DecodedAttrib* attrib, void* heap)
{
PKCS7DecodedAttrib* current;
if (attrib == NULL) {
return;
}
current = attrib;
while (current != NULL) {
PKCS7DecodedAttrib* next = current->next;
if (current->oid != NULL) {
XFREE(current->oid, heap, DYNAMIC_TYPE_PKCS7);
}
if (current->value != NULL) {
XFREE(current->value, heap, DYNAMIC_TYPE_PKCS7);
}
XFREE(current, heap, DYNAMIC_TYPE_PKCS7);
current = next;
}
(void)heap;
}
/* releases any memory allocated by a PKCS7 initializer */
void wc_PKCS7_Free(PKCS7* pkcs7)
{
if (pkcs7 == NULL)
return;
wc_PKCS7_FreeDecodedAttrib(pkcs7->decodedAttrib, pkcs7->heap);
}
/* build PKCS#7 data content type */
int wc_PKCS7_EncodeData(PKCS7* pkcs7, byte* output, word32 outputSz)
{
static const byte oid[] =
{ ASN_OBJECT_ID, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01,
0x07, 0x01 };
byte seq[MAX_SEQ_SZ];
byte octetStr[MAX_OCTET_STR_SZ];
word32 seqSz;
word32 octetStrSz;
word32 oidSz = (word32)sizeof(oid);
int idx = 0;
octetStrSz = SetOctetString(pkcs7->contentSz, octetStr);
seqSz = SetSequence(pkcs7->contentSz + octetStrSz + oidSz, seq);
if (outputSz < pkcs7->contentSz + octetStrSz + oidSz + seqSz)
return BUFFER_E;
XMEMCPY(output, seq, seqSz);
idx += seqSz;
XMEMCPY(output + idx, oid, oidSz);
idx += oidSz;
XMEMCPY(output + idx, octetStr, octetStrSz);
idx += octetStrSz;
XMEMCPY(output + idx, pkcs7->content, pkcs7->contentSz);
idx += pkcs7->contentSz;
return idx;
}
typedef struct EncodedAttrib {
byte valueSeq[MAX_SEQ_SZ];
const byte* oid;
byte valueSet[MAX_SET_SZ];
const byte* value;
word32 valueSeqSz, oidSz, idSz, valueSetSz, valueSz, totalSz;
} EncodedAttrib;
typedef struct ESD {
Sha sha;
byte contentDigest[SHA_DIGEST_SIZE + 2]; /* content only + ASN.1 heading */
byte contentAttribsDigest[SHA_DIGEST_SIZE];
byte encContentDigest[512];
byte outerSeq[MAX_SEQ_SZ];
byte outerContent[MAX_EXP_SZ];
byte innerSeq[MAX_SEQ_SZ];
byte version[MAX_VERSION_SZ];
byte digAlgoIdSet[MAX_SET_SZ];
byte singleDigAlgoId[MAX_ALGO_SZ];
byte contentInfoSeq[MAX_SEQ_SZ];
byte innerContSeq[MAX_EXP_SZ];
byte innerOctets[MAX_OCTET_STR_SZ];
byte certsSet[MAX_SET_SZ];
byte signerInfoSet[MAX_SET_SZ];
byte signerInfoSeq[MAX_SEQ_SZ];
byte signerVersion[MAX_VERSION_SZ];
byte issuerSnSeq[MAX_SEQ_SZ];
byte issuerName[MAX_SEQ_SZ];
byte issuerSn[MAX_SN_SZ];
byte signerDigAlgoId[MAX_ALGO_SZ];
byte digEncAlgoId[MAX_ALGO_SZ];
byte signedAttribSet[MAX_SET_SZ];
EncodedAttrib signedAttribs[6];
byte signerDigest[MAX_OCTET_STR_SZ];
word32 innerOctetsSz, innerContSeqSz, contentInfoSeqSz;
word32 outerSeqSz, outerContentSz, innerSeqSz, versionSz, digAlgoIdSetSz,
singleDigAlgoIdSz, certsSetSz;
word32 signerInfoSetSz, signerInfoSeqSz, signerVersionSz,
issuerSnSeqSz, issuerNameSz, issuerSnSz,
signerDigAlgoIdSz, digEncAlgoIdSz, signerDigestSz;
word32 encContentDigestSz, signedAttribsSz, signedAttribsCount,
signedAttribSetSz;
} ESD;
static int EncodeAttributes(EncodedAttrib* ea, int eaSz,
PKCS7Attrib* attribs, int attribsSz)
{
int i;
int maxSz = min(eaSz, attribsSz);
int allAttribsSz = 0;
for (i = 0; i < maxSz; i++)
{
int attribSz = 0;
ea[i].value = attribs[i].value;
ea[i].valueSz = attribs[i].valueSz;
attribSz += ea[i].valueSz;
ea[i].valueSetSz = SetSet(attribSz, ea[i].valueSet);
attribSz += ea[i].valueSetSz;
ea[i].oid = attribs[i].oid;
ea[i].oidSz = attribs[i].oidSz;
attribSz += ea[i].oidSz;
ea[i].valueSeqSz = SetSequence(attribSz, ea[i].valueSeq);
attribSz += ea[i].valueSeqSz;
ea[i].totalSz = attribSz;
allAttribsSz += attribSz;
}
return allAttribsSz;
}
static int FlattenAttributes(byte* output, EncodedAttrib* ea, int eaSz)
{
int i, idx;
idx = 0;
for (i = 0; i < eaSz; i++) {
XMEMCPY(output + idx, ea[i].valueSeq, ea[i].valueSeqSz);
idx += ea[i].valueSeqSz;
XMEMCPY(output + idx, ea[i].oid, ea[i].oidSz);
idx += ea[i].oidSz;
XMEMCPY(output + idx, ea[i].valueSet, ea[i].valueSetSz);
idx += ea[i].valueSetSz;
XMEMCPY(output + idx, ea[i].value, ea[i].valueSz);
idx += ea[i].valueSz;
}
return 0;
}
/* build PKCS#7 signedData content type */
int wc_PKCS7_EncodeSignedData(PKCS7* pkcs7, byte* output, word32 outputSz)
{
static const byte outerOid[] =
{ ASN_OBJECT_ID, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01,
0x07, 0x02 };
static const byte innerOid[] =
{ ASN_OBJECT_ID, 0x09, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0x0D, 0x01,
0x07, 0x01 };
#ifdef WOLFSSL_SMALL_STACK
ESD* esd = NULL;
#else
ESD stack_esd;
ESD* esd = &stack_esd;
#endif
word32 signerInfoSz = 0;
word32 totalSz = 0;
int idx = 0, ret = 0;
byte* flatSignedAttribs = NULL;
word32 flatSignedAttribsSz = 0;
word32 innerOidSz = sizeof(innerOid);
word32 outerOidSz = sizeof(outerOid);
if (pkcs7 == NULL || pkcs7->content == NULL || pkcs7->contentSz == 0 ||
pkcs7->encryptOID == 0 || pkcs7->hashOID == 0 || pkcs7->rng == 0 ||
pkcs7->singleCert == NULL || pkcs7->singleCertSz == 0 ||
pkcs7->privateKey == NULL || pkcs7->privateKeySz == 0 ||
output == NULL || outputSz == 0)
return BAD_FUNC_ARG;
#ifdef WOLFSSL_SMALL_STACK
esd = (ESD*)XMALLOC(sizeof(ESD), NULL, DYNAMIC_TYPE_TMP_BUFFER);
if (esd == NULL)
return MEMORY_E;
#endif
XMEMSET(esd, 0, sizeof(ESD));
ret = wc_InitSha(&esd->sha);
if (ret != 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(esd, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ret;
}
if (pkcs7->contentSz != 0)
{
wc_ShaUpdate(&esd->sha, pkcs7->content, pkcs7->contentSz);
esd->contentDigest[0] = ASN_OCTET_STRING;
esd->contentDigest[1] = SHA_DIGEST_SIZE;
wc_ShaFinal(&esd->sha, &esd->contentDigest[2]);
}
esd->innerOctetsSz = SetOctetString(pkcs7->contentSz, esd->innerOctets);
esd->innerContSeqSz = SetExplicit(0, esd->innerOctetsSz + pkcs7->contentSz,
esd->innerContSeq);
esd->contentInfoSeqSz = SetSequence(pkcs7->contentSz + esd->innerOctetsSz +
innerOidSz + esd->innerContSeqSz,
esd->contentInfoSeq);
esd->issuerSnSz = SetSerialNumber(pkcs7->issuerSn, pkcs7->issuerSnSz,
esd->issuerSn);
signerInfoSz += esd->issuerSnSz;
esd->issuerNameSz = SetSequence(pkcs7->issuerSz, esd->issuerName);
signerInfoSz += esd->issuerNameSz + pkcs7->issuerSz;
esd->issuerSnSeqSz = SetSequence(signerInfoSz, esd->issuerSnSeq);
signerInfoSz += esd->issuerSnSeqSz;
esd->signerVersionSz = SetMyVersion(1, esd->signerVersion, 0);
signerInfoSz += esd->signerVersionSz;
esd->signerDigAlgoIdSz = SetAlgoID(pkcs7->hashOID, esd->signerDigAlgoId,
oidHashType, 0);
signerInfoSz += esd->signerDigAlgoIdSz;
esd->digEncAlgoIdSz = SetAlgoID(pkcs7->encryptOID, esd->digEncAlgoId,
oidKeyType, 0);
signerInfoSz += esd->digEncAlgoIdSz;
if (pkcs7->signedAttribsSz != 0) {
byte contentTypeOid[] =
{ ASN_OBJECT_ID, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xF7, 0x0d, 0x01,
0x09, 0x03 };
byte contentType[] =
{ ASN_OBJECT_ID, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01,
0x07, 0x01 };
byte messageDigestOid[] =
{ ASN_OBJECT_ID, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01,
0x09, 0x04 };
PKCS7Attrib cannedAttribs[2] ;
word32 cannedAttribsCount = sizeof(cannedAttribs)/sizeof(PKCS7Attrib);
cannedAttribs[0].oid = contentTypeOid ;
cannedAttribs[0].oidSz = sizeof(contentTypeOid) ;
cannedAttribs[0].value = contentType ;
cannedAttribs[0].valueSz = sizeof(contentType) ;
cannedAttribs[1].oid = messageDigestOid ;
cannedAttribs[1].oidSz = sizeof(messageDigestOid) ;
cannedAttribs[1].value = esd->contentDigest ;
cannedAttribs[1].valueSz = sizeof(esd->contentDigest) ;
esd->signedAttribsCount += cannedAttribsCount;
esd->signedAttribsSz += EncodeAttributes(&esd->signedAttribs[0], 2,
cannedAttribs, cannedAttribsCount);
esd->signedAttribsCount += pkcs7->signedAttribsSz;
esd->signedAttribsSz += EncodeAttributes(&esd->signedAttribs[2], 4,
pkcs7->signedAttribs, pkcs7->signedAttribsSz);
flatSignedAttribs = (byte*)XMALLOC(esd->signedAttribsSz, pkcs7->heap,
DYNAMIC_TYPE_PKCS);
flatSignedAttribsSz = esd->signedAttribsSz;
if (flatSignedAttribs == NULL) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(esd, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return MEMORY_E;
}
FlattenAttributes(flatSignedAttribs,
esd->signedAttribs, esd->signedAttribsCount);
esd->signedAttribSetSz = SetImplicit(ASN_SET, 0, esd->signedAttribsSz,
esd->signedAttribSet);
}
/* Calculate the final hash and encrypt it. */
{
int result;
word32 scratch = 0;
#ifdef WOLFSSL_SMALL_STACK
byte* digestInfo;
RsaKey* privKey;
#else
RsaKey stack_privKey;
RsaKey* privKey = &stack_privKey;
byte digestInfo[MAX_SEQ_SZ + MAX_ALGO_SZ +
MAX_OCTET_STR_SZ + SHA_DIGEST_SIZE];
#endif
byte digestInfoSeq[MAX_SEQ_SZ];
byte digestStr[MAX_OCTET_STR_SZ];
word32 digestInfoSeqSz, digestStrSz;
int digIdx = 0;
if (pkcs7->signedAttribsSz != 0) {
byte attribSet[MAX_SET_SZ];
word32 attribSetSz;
attribSetSz = SetSet(flatSignedAttribsSz, attribSet);
ret = wc_InitSha(&esd->sha);
if (ret < 0) {
XFREE(flatSignedAttribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
#ifdef WOLFSSL_SMALL_STACK
XFREE(esd, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ret;
}
wc_ShaUpdate(&esd->sha, attribSet, attribSetSz);
wc_ShaUpdate(&esd->sha, flatSignedAttribs, flatSignedAttribsSz);
wc_ShaFinal(&esd->sha, esd->contentAttribsDigest);
} else {
/* when no attrs, digest is contentDigest without tag and length */
XMEMCPY(esd->contentAttribsDigest, esd->contentDigest + 2,
SHA_DIGEST_SIZE);
}
digestStrSz = SetOctetString(SHA_DIGEST_SIZE, digestStr);
digestInfoSeqSz = SetSequence(esd->signerDigAlgoIdSz +
digestStrSz + SHA_DIGEST_SIZE,
digestInfoSeq);
#ifdef WOLFSSL_SMALL_STACK
digestInfo = (byte*)XMALLOC(MAX_SEQ_SZ + MAX_ALGO_SZ +
MAX_OCTET_STR_SZ + SHA_DIGEST_SIZE,
NULL, DYNAMIC_TYPE_TMP_BUFFER);
if (digestInfo == NULL) {
if (pkcs7->signedAttribsSz != 0)
XFREE(flatSignedAttribs, 0, NULL);
XFREE(esd, NULL, DYNAMIC_TYPE_TMP_BUFFER);
return MEMORY_E;
}
#endif
XMEMCPY(digestInfo + digIdx, digestInfoSeq, digestInfoSeqSz);
digIdx += digestInfoSeqSz;
XMEMCPY(digestInfo + digIdx,
esd->signerDigAlgoId, esd->signerDigAlgoIdSz);
digIdx += esd->signerDigAlgoIdSz;
XMEMCPY(digestInfo + digIdx, digestStr, digestStrSz);
digIdx += digestStrSz;
XMEMCPY(digestInfo + digIdx, esd->contentAttribsDigest,
SHA_DIGEST_SIZE);
digIdx += SHA_DIGEST_SIZE;
#ifdef WOLFSSL_SMALL_STACK
privKey = (RsaKey*)XMALLOC(sizeof(RsaKey), NULL,
DYNAMIC_TYPE_TMP_BUFFER);
if (privKey == NULL) {
if (pkcs7->signedAttribsSz != 0)
XFREE(flatSignedAttribs, 0, NULL);
XFREE(digestInfo, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(esd, NULL, DYNAMIC_TYPE_TMP_BUFFER);
return MEMORY_E;
}
#endif
result = wc_InitRsaKey(privKey, pkcs7->heap);
if (result == 0)
result = wc_RsaPrivateKeyDecode(pkcs7->privateKey, &scratch, privKey,
pkcs7->privateKeySz);
if (result < 0) {
if (pkcs7->signedAttribsSz != 0)
XFREE(flatSignedAttribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
#ifdef WOLFSSL_SMALL_STACK
XFREE(privKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(digestInfo, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(esd, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return PUBLIC_KEY_E;
}
result = wc_RsaSSL_Sign(digestInfo, digIdx,
esd->encContentDigest,
sizeof(esd->encContentDigest),
privKey, pkcs7->rng);
wc_FreeRsaKey(privKey);
#ifdef WOLFSSL_SMALL_STACK
XFREE(privKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(digestInfo, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
if (result < 0) {
if (pkcs7->signedAttribsSz != 0)
XFREE(flatSignedAttribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
#ifdef WOLFSSL_SMALL_STACK
XFREE(esd, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return result;
}
esd->encContentDigestSz = (word32)result;
}
signerInfoSz += flatSignedAttribsSz + esd->signedAttribSetSz;
esd->signerDigestSz = SetOctetString(esd->encContentDigestSz,
esd->signerDigest);
signerInfoSz += esd->signerDigestSz + esd->encContentDigestSz;
esd->signerInfoSeqSz = SetSequence(signerInfoSz, esd->signerInfoSeq);
signerInfoSz += esd->signerInfoSeqSz;
esd->signerInfoSetSz = SetSet(signerInfoSz, esd->signerInfoSet);
signerInfoSz += esd->signerInfoSetSz;
esd->certsSetSz = SetImplicit(ASN_SET, 0, pkcs7->singleCertSz,
esd->certsSet);
esd->singleDigAlgoIdSz = SetAlgoID(pkcs7->hashOID, esd->singleDigAlgoId,
oidHashType, 0);
esd->digAlgoIdSetSz = SetSet(esd->singleDigAlgoIdSz, esd->digAlgoIdSet);
esd->versionSz = SetMyVersion(1, esd->version, 0);
totalSz = esd->versionSz + esd->singleDigAlgoIdSz + esd->digAlgoIdSetSz +
esd->contentInfoSeqSz + esd->certsSetSz + pkcs7->singleCertSz +
esd->innerOctetsSz + esd->innerContSeqSz +
innerOidSz + pkcs7->contentSz +
signerInfoSz;
esd->innerSeqSz = SetSequence(totalSz, esd->innerSeq);
totalSz += esd->innerSeqSz;
esd->outerContentSz = SetExplicit(0, totalSz, esd->outerContent);
totalSz += esd->outerContentSz + outerOidSz;
esd->outerSeqSz = SetSequence(totalSz, esd->outerSeq);
totalSz += esd->outerSeqSz;
if (outputSz < totalSz) {
if (pkcs7->signedAttribsSz != 0)
XFREE(flatSignedAttribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
#ifdef WOLFSSL_SMALL_STACK
XFREE(esd, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return BUFFER_E;
}
idx = 0;
XMEMCPY(output + idx, esd->outerSeq, esd->outerSeqSz);
idx += esd->outerSeqSz;
XMEMCPY(output + idx, outerOid, outerOidSz);
idx += outerOidSz;
XMEMCPY(output + idx, esd->outerContent, esd->outerContentSz);
idx += esd->outerContentSz;
XMEMCPY(output + idx, esd->innerSeq, esd->innerSeqSz);
idx += esd->innerSeqSz;
XMEMCPY(output + idx, esd->version, esd->versionSz);
idx += esd->versionSz;
XMEMCPY(output + idx, esd->digAlgoIdSet, esd->digAlgoIdSetSz);
idx += esd->digAlgoIdSetSz;
XMEMCPY(output + idx, esd->singleDigAlgoId, esd->singleDigAlgoIdSz);
idx += esd->singleDigAlgoIdSz;
XMEMCPY(output + idx, esd->contentInfoSeq, esd->contentInfoSeqSz);
idx += esd->contentInfoSeqSz;
XMEMCPY(output + idx, innerOid, innerOidSz);
idx += innerOidSz;
XMEMCPY(output + idx, esd->innerContSeq, esd->innerContSeqSz);
idx += esd->innerContSeqSz;
XMEMCPY(output + idx, esd->innerOctets, esd->innerOctetsSz);
idx += esd->innerOctetsSz;
XMEMCPY(output + idx, pkcs7->content, pkcs7->contentSz);
idx += pkcs7->contentSz;
XMEMCPY(output + idx, esd->certsSet, esd->certsSetSz);
idx += esd->certsSetSz;
XMEMCPY(output + idx, pkcs7->singleCert, pkcs7->singleCertSz);
idx += pkcs7->singleCertSz;
XMEMCPY(output + idx, esd->signerInfoSet, esd->signerInfoSetSz);
idx += esd->signerInfoSetSz;
XMEMCPY(output + idx, esd->signerInfoSeq, esd->signerInfoSeqSz);
idx += esd->signerInfoSeqSz;
XMEMCPY(output + idx, esd->signerVersion, esd->signerVersionSz);
idx += esd->signerVersionSz;
XMEMCPY(output + idx, esd->issuerSnSeq, esd->issuerSnSeqSz);
idx += esd->issuerSnSeqSz;
XMEMCPY(output + idx, esd->issuerName, esd->issuerNameSz);
idx += esd->issuerNameSz;
XMEMCPY(output + idx, pkcs7->issuer, pkcs7->issuerSz);
idx += pkcs7->issuerSz;
XMEMCPY(output + idx, esd->issuerSn, esd->issuerSnSz);
idx += esd->issuerSnSz;
XMEMCPY(output + idx, esd->signerDigAlgoId, esd->signerDigAlgoIdSz);
idx += esd->signerDigAlgoIdSz;
/* SignerInfo:Attributes */
if (pkcs7->signedAttribsSz != 0) {
XMEMCPY(output + idx, esd->signedAttribSet, esd->signedAttribSetSz);
idx += esd->signedAttribSetSz;
XMEMCPY(output + idx, flatSignedAttribs, flatSignedAttribsSz);
idx += flatSignedAttribsSz;
XFREE(flatSignedAttribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
}
XMEMCPY(output + idx, esd->digEncAlgoId, esd->digEncAlgoIdSz);
idx += esd->digEncAlgoIdSz;
XMEMCPY(output + idx, esd->signerDigest, esd->signerDigestSz);
idx += esd->signerDigestSz;
XMEMCPY(output + idx, esd->encContentDigest, esd->encContentDigestSz);
idx += esd->encContentDigestSz;
#ifdef WOLFSSL_SMALL_STACK
XFREE(esd, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return idx;
}
/* Finds the certificates in the message and saves it. */
int wc_PKCS7_VerifySignedData(PKCS7* pkcs7, byte* pkiMsg, word32 pkiMsgSz)
{
word32 idx, contentType;
int length, version, ret;
byte* content = NULL;
byte* sig = NULL;
byte* cert = NULL;
int contentSz = 0, sigSz = 0, certSz = 0;
if (pkcs7 == NULL || pkiMsg == NULL || pkiMsgSz == 0)
return BAD_FUNC_ARG;
idx = 0;
/* Get the contentInfo sequence */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Get the contentInfo contentType */
if (wc_GetContentType(pkiMsg, &idx, &contentType, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (contentType != SIGNED_DATA) {
WOLFSSL_MSG("PKCS#7 input not of type SignedData");
return PKCS7_OID_E;
}
/* get the ContentInfo content */
if (pkiMsg[idx++] != (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 0))
return ASN_PARSE_E;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Get the signedData sequence */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Get the version */
if (GetMyVersion(pkiMsg, &idx, &version, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (version != 1) {
WOLFSSL_MSG("PKCS#7 signedData needs to be of version 1");
return ASN_VERSION_E;
}
/* Get the set of DigestAlgorithmIdentifiers */
if (GetSet(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Skip the set. */
idx += length;
/* Get the inner ContentInfo sequence */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Get the inner ContentInfo contentType */
if (wc_GetContentType(pkiMsg, &idx, &contentType, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (contentType != DATA) {
WOLFSSL_MSG("PKCS#7 inner input not of type Data");
return PKCS7_OID_E;
}
if (pkiMsg[idx++] != (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 0))
return ASN_PARSE_E;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) <= 0)
return ASN_PARSE_E;
if (pkiMsg[idx++] != ASN_OCTET_STRING)
return ASN_PARSE_E;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Save the inner data as the content. */
if (length > 0) {
/* Local pointer for calculating hashes later */
pkcs7->content = content = &pkiMsg[idx];
pkcs7->contentSz = contentSz = length;
idx += length;
}
/* Get the implicit[0] set of certificates */
if (pkiMsg[idx] == (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 0)) {
idx++;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (length > 0) {
/* At this point, idx is at the first certificate in
* a set of certificates. There may be more than one,
* or none, or they may be a PKCS 6 extended
* certificate. We want to save the first cert if it
* is X.509. */
word32 certIdx = idx;
if (pkiMsg[certIdx++] == (ASN_CONSTRUCTED | ASN_SEQUENCE)) {
if (GetLength(pkiMsg, &certIdx, &certSz, pkiMsgSz) < 0)
return ASN_PARSE_E;
cert = &pkiMsg[idx];
certSz += (certIdx - idx);
}
wc_PKCS7_InitWithCert(pkcs7, cert, certSz);
}
idx += length;
}
/* Get the implicit[1] set of crls */
if (pkiMsg[idx] == (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 1)) {
idx++;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Skip the set */
idx += length;
}
/* Get the set of signerInfos */
if (GetSet(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (length > 0) {
/* Get the sequence of the first signerInfo */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Get the version */
if (GetMyVersion(pkiMsg, &idx, &version, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (version != 1) {
WOLFSSL_MSG("PKCS#7 signerInfo needs to be of version 1");
return ASN_VERSION_E;
}
/* Get the sequence of IssuerAndSerialNumber */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Skip it */
idx += length;
/* Get the sequence of digestAlgorithm */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Skip it */
idx += length;
/* Get the IMPLICIT[0] SET OF signedAttributes */
if (pkiMsg[idx] == (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 0)) {
idx++;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
idx += length;
}
/* Get the sequence of digestEncryptionAlgorithm */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* Skip it */
idx += length;
/* Get the signature */
if (pkiMsg[idx] == ASN_OCTET_STRING) {
idx++;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* save pointer and length */
sig = &pkiMsg[idx];
sigSz = length;
idx += length;
}
pkcs7->content = content;
pkcs7->contentSz = contentSz;
{
word32 scratch = 0;
int plainSz = 0;
#define MAX_PKCS7_DIGEST_SZ (MAX_SEQ_SZ + MAX_ALGO_SZ +\
MAX_OCTET_STR_SZ + SHA_DIGEST_SIZE)
#ifdef WOLFSSL_SMALL_STACK
byte* digest;
RsaKey* key;
digest = (byte*)XMALLOC(MAX_PKCS7_DIGEST_SZ, NULL,
DYNAMIC_TYPE_TMP_BUFFER);
if (digest == NULL)
return MEMORY_E;
key = (RsaKey*)XMALLOC(sizeof(RsaKey), NULL,
DYNAMIC_TYPE_TMP_BUFFER);
if (key == NULL) {
XFREE(digest, NULL, DYNAMIC_TYPE_TMP_BUFFER);
return MEMORY_E;
}
#else
byte digest[MAX_PKCS7_DIGEST_SZ];
RsaKey stack_key;
RsaKey* key = &stack_key;
#endif
XMEMSET(digest, 0, MAX_PKCS7_DIGEST_SZ);
ret = wc_InitRsaKey(key, pkcs7->heap);
if (ret != 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(digest, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(key, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ret;
}
if (wc_RsaPublicKeyDecode(pkcs7->publicKey, &scratch, key,
pkcs7->publicKeySz) < 0) {
WOLFSSL_MSG("ASN RSA key decode error");
#ifdef WOLFSSL_SMALL_STACK
XFREE(digest, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(key, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return PUBLIC_KEY_E;
}
plainSz = wc_RsaSSL_Verify(sig, sigSz, digest, MAX_PKCS7_DIGEST_SZ,
key);
wc_FreeRsaKey(key);
#ifdef WOLFSSL_SMALL_STACK
XFREE(digest, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(key, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
if (plainSz < 0)
return plainSz;
}
}
return 0;
}
/* KARI == KeyAgreeRecipientInfo (key agreement) */
typedef struct WC_PKCS7_KARI {
DecodedCert* decoded; /* decoded recip cert */
void* heap; /* user heap, points to PKCS7->heap */
ecc_key* recipKey; /* recip key (pub | priv) */
ecc_key* senderKey; /* sender key (pub | priv) */
byte* senderKeyExport; /* sender ephemeral key DER */
byte* kek; /* key encryption key */
byte* ukm; /* OPTIONAL user keying material */
byte* sharedInfo; /* ECC-CMS-SharedInfo ASN.1 encoded blob */
word32 senderKeyExportSz; /* size of sender ephemeral key DER */
word32 kekSz; /* size of key encryption key */
word32 ukmSz; /* size of user keying material */
word32 sharedInfoSz; /* size of ECC-CMS-SharedInfo encoded */
byte ukmOwner; /* do we own ukm buffer? 1:yes, 0:no */
byte direction; /* WC_PKCS7_ENCODE | WC_PKCS7_DECODE */
} WC_PKCS7_KARI;
/* wrap CEK (content encryption key) with KEK, 0 on success, < 0 on error */
static int wc_PKCS7_KariKeyWrap(byte* cek, word32 cekSz, byte* kek,
word32 kekSz, byte* out, word32 outSz,
int keyWrapAlgo, int direction)
{
int ret;
if (cek == NULL || kek == NULL || out == NULL)
return BAD_FUNC_ARG;
switch (keyWrapAlgo) {
#ifndef NO_AES
case AES128_WRAP:
case AES192_WRAP:
case AES256_WRAP:
if (direction == AES_ENCRYPTION) {
ret = wc_AesKeyWrap(kek, kekSz, cek, cekSz,
out, outSz, NULL);
} else if (direction == AES_DECRYPTION) {
ret = wc_AesKeyUnWrap(kek, kekSz, cek, cekSz,
out, outSz, NULL);
} else {
WOLFSSL_MSG("Bad key un/wrap direction");
return BAD_FUNC_ARG;
}
if (ret <= 0)
return ret;
break;
#endif /* NO_AES */
default:
WOLFSSL_MSG("Unsupported key wrap algorithm");
return BAD_KEYWRAP_ALG_E;
};
(void)cekSz;
(void)kekSz;
(void)outSz;
(void)direction;
return ret;
}
/* allocate and create new WC_PKCS7_KARI struct,
* returns struct pointer on success, NULL on failure */
static WC_PKCS7_KARI* wc_PKCS7_KariNew(PKCS7* pkcs7, byte direction)
{
WC_PKCS7_KARI* kari = NULL;
if (pkcs7 == NULL)
return NULL;
kari = (WC_PKCS7_KARI*)XMALLOC(sizeof(WC_PKCS7_KARI), pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (kari == NULL) {
WOLFSSL_MSG("Failed to allocate WC_PKCS7_KARI");
return NULL;
}
kari->decoded = (DecodedCert*)XMALLOC(sizeof(DecodedCert), pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (kari->decoded == NULL) {
WOLFSSL_MSG("Failed to allocate DecodedCert");
XFREE(kari, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return NULL;
}
kari->recipKey = (ecc_key*)XMALLOC(sizeof(ecc_key), pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (kari->recipKey == NULL) {
WOLFSSL_MSG("Failed to allocate recipient ecc_key");
XFREE(kari->decoded, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(kari, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return NULL;
}
kari->senderKey = (ecc_key*)XMALLOC(sizeof(ecc_key), pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (kari->senderKey == NULL) {
WOLFSSL_MSG("Failed to allocate sender ecc_key");
XFREE(kari->recipKey, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(kari->decoded, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(kari, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return NULL;
}
kari->senderKeyExport = NULL;
kari->senderKeyExportSz = 0;
kari->kek = NULL;
kari->kekSz = 0;
kari->ukm = NULL;
kari->ukmSz = 0;
kari->ukmOwner = 0;
kari->sharedInfo = NULL;
kari->sharedInfoSz = 0;
kari->direction = direction;
kari->heap = pkcs7->heap;
return kari;
}
/* free WC_PKCS7_KARI struct, return 0 on success */
static int wc_PKCS7_KariFree(WC_PKCS7_KARI* kari)
{
void* heap;
if (kari) {
heap = kari->heap;
if (kari->decoded) {
FreeDecodedCert(kari->decoded);
XFREE(kari->decoded, heap, DYNAMIC_TYPE_PKCS7);
}
if (kari->senderKey) {
wc_ecc_free(kari->senderKey);
XFREE(kari->senderKey, heap, DYNAMIC_TYPE_PKCS7);
}
if (kari->recipKey) {
wc_ecc_free(kari->recipKey);
XFREE(kari->recipKey, heap, DYNAMIC_TYPE_PKCS7);
}
if (kari->senderKeyExport) {
ForceZero(kari->senderKeyExport, kari->senderKeyExportSz);
XFREE(kari->senderKeyExport, heap, DYNAMIC_TYPE_PKCS7);
kari->senderKeyExportSz = 0;
}
if (kari->kek) {
ForceZero(kari->kek, kari->kekSz);
XFREE(kari->kek, heap, DYNAMIC_TYPE_PKCS7);
kari->kekSz = 0;
}
if (kari->ukm) {
if (kari->ukmOwner == 1) {
XFREE(kari->ukm, heap, DYNAMIC_TYPE_PKCS7);
}
kari->ukmSz = 0;
}
if (kari->sharedInfo) {
ForceZero(kari->sharedInfo, kari->sharedInfoSz);
XFREE(kari->sharedInfo, heap, DYNAMIC_TYPE_PKCS7);
kari->sharedInfoSz = 0;
}
XFREE(kari, heap, DYNAMIC_TYPE_PKCS7);
}
(void)heap;
return 0;
}
/* parse recipient cert/key, return 0 on success, negative on error
* key/keySz only needed during decoding (WC_PKCS7_DECODE) */
static int wc_PKCS7_KariParseRecipCert(WC_PKCS7_KARI* kari, const byte* cert,
word32 certSz, const byte* key,
word32 keySz)
{
int ret;
word32 idx;
if (kari == NULL || kari->decoded == NULL ||
cert == NULL || certSz == 0)
return BAD_FUNC_ARG;
if (kari->direction == WC_PKCS7_DECODE &&
(key == NULL || keySz == 0))
return BAD_FUNC_ARG;
/* decode certificate */
InitDecodedCert(kari->decoded, (byte*)cert, certSz, kari->heap);
ret = ParseCert(kari->decoded, CA_TYPE, NO_VERIFY, 0);
if (ret < 0)
return ret;
/* make sure subject key id was read from cert */
if (kari->decoded->extSubjKeyIdSet == 0) {
WOLFSSL_MSG("Failed to read subject key ID from recipient cert");
return BAD_FUNC_ARG;
}
ret = wc_ecc_init(kari->recipKey);
if (ret != 0)
return ret;
/* get recip public key */
if (kari->direction == WC_PKCS7_ENCODE) {
ret = wc_ecc_import_x963(kari->decoded->publicKey,
kari->decoded->pubKeySize,
kari->recipKey);
}
/* get recip private key */
else if (kari->direction == WC_PKCS7_DECODE) {
idx = 0;
ret = wc_EccPrivateKeyDecode(key, &idx, kari->recipKey, keySz);
if (ret != 0)
return ret;
} else {
/* bad direction */
return BAD_FUNC_ARG;
}
if (ret != 0)
return ret;
(void)idx;
return 0;
}
/* create ephemeral ECC key, places ecc_key in kari->senderKey,
* DER encoded in kari->senderKeyExport. return 0 on success,
* negative on error */
static int wc_PKCS7_KariGenerateEphemeralKey(WC_PKCS7_KARI* kari, WC_RNG* rng)
{
int ret;
if (kari == NULL || kari->decoded == NULL ||
kari->recipKey == NULL || kari->recipKey->dp == NULL ||
rng == NULL)
return BAD_FUNC_ARG;
kari->senderKeyExport = (byte*)XMALLOC(kari->decoded->pubKeySize, kari->heap,
DYNAMIC_TYPE_PKCS7);
if (kari->senderKeyExport == NULL)
return MEMORY_E;
kari->senderKeyExportSz = kari->decoded->pubKeySize;
ret = wc_ecc_init_ex(kari->senderKey, kari->heap, INVALID_DEVID);
if (ret != 0)
return ret;
ret = wc_ecc_make_key_ex(rng, kari->recipKey->dp->size,
kari->senderKey, kari->recipKey->dp->id);
if (ret != 0)
return ret;
/* dump generated key to X.963 DER for output in CMS bundle */
ret = wc_ecc_export_x963(kari->senderKey, kari->senderKeyExport,
&kari->senderKeyExportSz);
if (ret != 0)
return ret;
return 0;
}
/* create ASN.1 encoded ECC-CMS-SharedInfo using specified key wrap algorithm,
* place in kari->sharedInfo. returns 0 on success, negative on error */
static int wc_PKCS7_KariGenerateSharedInfo(WC_PKCS7_KARI* kari, int keyWrapOID)
{
int idx = 0;
int sharedInfoSeqSz = 0;
int keyInfoSz = 0;
int suppPubInfoSeqSz = 0;
int entityUInfoOctetSz = 0;
int entityUInfoExplicitSz = 0;
int kekOctetSz = 0;
int sharedInfoSz = 0;
word32 kekBitSz = 0;
byte sharedInfoSeq[MAX_SEQ_SZ];
byte keyInfo[MAX_ALGO_SZ];
byte suppPubInfoSeq[MAX_SEQ_SZ];
byte entityUInfoOctet[MAX_OCTET_STR_SZ];
byte entityUInfoExplicitSeq[MAX_SEQ_SZ];
byte kekOctet[MAX_OCTET_STR_SZ];
if (kari == NULL)
return BAD_FUNC_ARG;
if ((kari->ukmSz > 0) && (kari->ukm == NULL))
return BAD_FUNC_ARG;
/* kekOctet */
kekOctetSz = SetOctetString(sizeof(word32), kekOctet);
sharedInfoSz += (kekOctetSz + sizeof(word32));
/* suppPubInfo */
suppPubInfoSeqSz = SetImplicit(ASN_SEQUENCE, 2,
kekOctetSz + sizeof(word32),
suppPubInfoSeq);
sharedInfoSz += suppPubInfoSeqSz;
/* optional ukm/entityInfo */
if (kari->ukmSz > 0) {
entityUInfoOctetSz = SetOctetString(kari->ukmSz, entityUInfoOctet);
sharedInfoSz += (entityUInfoOctetSz + kari->ukmSz);
entityUInfoExplicitSz = SetExplicit(0, entityUInfoOctetSz +
kari->ukmSz,
entityUInfoExplicitSeq);
sharedInfoSz += entityUInfoExplicitSz;
}
/* keyInfo */
keyInfoSz = SetAlgoID(keyWrapOID, keyInfo, oidKeyWrapType, 0);
sharedInfoSz += keyInfoSz;
/* sharedInfo */
sharedInfoSeqSz = SetSequence(sharedInfoSz, sharedInfoSeq);
sharedInfoSz += sharedInfoSeqSz;
kari->sharedInfo = (byte*)XMALLOC(sharedInfoSz, kari->heap,
DYNAMIC_TYPE_PKCS7);
if (kari->sharedInfo == NULL)
return MEMORY_E;
kari->sharedInfoSz = sharedInfoSz;
XMEMCPY(kari->sharedInfo + idx, sharedInfoSeq, sharedInfoSeqSz);
idx += sharedInfoSeqSz;
XMEMCPY(kari->sharedInfo + idx, keyInfo, keyInfoSz);
idx += keyInfoSz;
if (kari->ukmSz > 0) {
XMEMCPY(kari->sharedInfo + idx, entityUInfoExplicitSeq,
entityUInfoExplicitSz);
idx += entityUInfoExplicitSz;
XMEMCPY(kari->sharedInfo + idx, entityUInfoOctet, entityUInfoOctetSz);
idx += entityUInfoOctetSz;
XMEMCPY(kari->sharedInfo + idx, kari->ukm, kari->ukmSz);
idx += kari->ukmSz;
}
XMEMCPY(kari->sharedInfo + idx, suppPubInfoSeq, suppPubInfoSeqSz);
idx += suppPubInfoSeqSz;
XMEMCPY(kari->sharedInfo + idx, kekOctet, kekOctetSz);
idx += kekOctetSz;
kekBitSz = (kari->kekSz) * 8; /* convert to bits */
#ifdef LITTLE_ENDIAN_ORDER
kekBitSz = ByteReverseWord32(kekBitSz); /* network byte order */
#endif
XMEMCPY(kari->sharedInfo + idx, &kekBitSz, sizeof(kekBitSz));
return 0;
}
/* create key encryption key (KEK) using key wrap algorithm and key encryption
* algorithm, place in kari->kek. return 0 on success, <0 on error. */
static int wc_PKCS7_KariGenerateKEK(WC_PKCS7_KARI* kari,
int keyWrapOID, int keyEncOID)
{
int ret;
int kSz;
enum wc_HashType kdfType;
byte* secret;
word32 secretSz;
if (kari == NULL || kari->recipKey == NULL ||
kari->senderKey == NULL || kari->senderKey->dp == NULL)
return BAD_FUNC_ARG;
/* get KEK size, allocate buff */
kSz = wc_PKCS7_GetOIDKeySize(keyWrapOID);
if (kSz < 0)
return kSz;
kari->kek = (byte*)XMALLOC(kSz, kari->heap, DYNAMIC_TYPE_PKCS7);
if (kari->kek == NULL)
return MEMORY_E;
kari->kekSz = (word32)kSz;
/* generate ECC-CMS-SharedInfo */
ret = wc_PKCS7_KariGenerateSharedInfo(kari, keyWrapOID);
if (ret != 0)
return ret;
/* generate shared secret */
secretSz = kari->senderKey->dp->size;
secret = (byte*)XMALLOC(secretSz, kari->heap, DYNAMIC_TYPE_PKCS7);
if (secret == NULL)
return MEMORY_E;
if (kari->direction == WC_PKCS7_ENCODE) {
ret = wc_ecc_shared_secret(kari->senderKey, kari->recipKey,
secret, &secretSz);
} else if (kari->direction == WC_PKCS7_DECODE) {
ret = wc_ecc_shared_secret(kari->recipKey, kari->senderKey,
secret, &secretSz);
} else {
/* bad direction */
XFREE(secret, kari->heap, DYNAMIC_TYPE_PKCS7);
return BAD_FUNC_ARG;
}
if (ret != 0) {
XFREE(secret, kari->heap, DYNAMIC_TYPE_PKCS7);
return ret;
}
/* run through KDF */
switch (keyEncOID) {
#ifndef NO_SHA
case dhSinglePass_stdDH_sha1kdf_scheme:
kdfType = WC_HASH_TYPE_SHA;
break;
#endif
#ifndef WOLFSSL_SHA224
case dhSinglePass_stdDH_sha224kdf_scheme:
kdfType = WC_HASH_TYPE_SHA224;
break;
#endif
#ifndef NO_SHA256
case dhSinglePass_stdDH_sha256kdf_scheme:
kdfType = WC_HASH_TYPE_SHA256;
break;
#endif
#ifdef WOLFSSL_SHA384
case dhSinglePass_stdDH_sha384kdf_scheme:
kdfType = WC_HASH_TYPE_SHA384;
break;
#endif
#ifdef WOLFSSL_SHA512
case dhSinglePass_stdDH_sha512kdf_scheme:
kdfType = WC_HASH_TYPE_SHA512;
break;
#endif
default:
WOLFSSL_MSG("Unsupported key agreement algorithm");
XFREE(secret, kari->heap, DYNAMIC_TYPE_PKCS7);
return BAD_FUNC_ARG;
};
ret = wc_X963_KDF(kdfType, secret, secretSz, kari->sharedInfo,
kari->sharedInfoSz, kari->kek, kari->kekSz);
if (ret != 0) {
XFREE(secret, kari->heap, DYNAMIC_TYPE_PKCS7);
return ret;
}
XFREE(secret, kari->heap, DYNAMIC_TYPE_PKCS7);
return 0;
}
/* create ASN.1 formatted KeyAgreeRecipientInfo (kari) for use with ECDH,
* return sequence size or negative on error */
static int wc_CreateKeyAgreeRecipientInfo(PKCS7* pkcs7, const byte* cert,
word32 certSz, int keyAgreeAlgo, int blockKeySz,
int keyWrapAlgo, int keyEncAlgo, WC_RNG* rng,
byte* contentKeyPlain, byte* contentKeyEnc,
int* keyEncSz, byte* out, word32 outSz)
{
int ret = 0, idx = 0;
int keySz, direction = 0;
/* ASN.1 layout */
int totalSz = 0;
int kariSeqSz = 0;
byte kariSeq[MAX_SEQ_SZ]; /* IMPLICIT [1] */
int verSz = 0;
byte ver[MAX_VERSION_SZ];
int origIdOrKeySeqSz = 0;
byte origIdOrKeySeq[MAX_SEQ_SZ]; /* IMPLICIT [0] */
int origPubKeySeqSz = 0;
byte origPubKeySeq[MAX_SEQ_SZ]; /* IMPLICIT [1] */
int origAlgIdSz = 0;
byte origAlgId[MAX_ALGO_SZ];
int origPubKeyStrSz = 0;
byte origPubKeyStr[MAX_OCTET_STR_SZ];
/* optional user keying material */
int ukmOctetSz = 0;
byte ukmOctetStr[MAX_OCTET_STR_SZ];
int ukmExplicitSz = 0;
byte ukmExplicitSeq[MAX_SEQ_SZ];
int keyEncryptAlgoIdSz = 0;
byte keyEncryptAlgoId[MAX_ALGO_SZ];
int keyWrapAlgSz = 0;
byte keyWrapAlg[MAX_ALGO_SZ];
int recipEncKeysSeqSz = 0;
byte recipEncKeysSeq[MAX_SEQ_SZ];
int recipEncKeySeqSz = 0;
byte recipEncKeySeq[MAX_SEQ_SZ];
int recipKeyIdSeqSz = 0;
byte recipKeyIdSeq[MAX_SEQ_SZ]; /* IMPLICIT [0] */
int subjKeyIdOctetSz = 0;
byte subjKeyIdOctet[MAX_OCTET_STR_SZ];
int encryptedKeyOctetSz = 0;
byte encryptedKeyOctet[MAX_OCTET_STR_SZ];
WC_PKCS7_KARI* kari;
/* only supports ECDSA for now */
if (keyAgreeAlgo != ECDSAk)
return BAD_FUNC_ARG;
/* set direction based on keyWrapAlgo */
switch (keyWrapAlgo) {
#ifndef NO_AES
case AES128_WRAP:
case AES192_WRAP:
case AES256_WRAP:
direction = AES_ENCRYPTION;
break;
#endif
default:
WOLFSSL_MSG("Unsupported key wrap algorithm");
return BAD_KEYWRAP_ALG_E;
}
kari = wc_PKCS7_KariNew(pkcs7, WC_PKCS7_ENCODE);
if (kari == NULL)
return MEMORY_E;
/* set user keying material if available */
if ((pkcs7->ukmSz > 0) && (pkcs7->ukm != NULL)) {
kari->ukm = pkcs7->ukm;
kari->ukmSz = pkcs7->ukmSz;
kari->ukmOwner = 0;
}
/* parse recipient cert, get public key */
ret = wc_PKCS7_KariParseRecipCert(kari, cert, certSz, NULL, 0);
if (ret != 0) {
wc_PKCS7_KariFree(kari);
return ret;
}
/* generate sender ephemeral ECC key */
ret = wc_PKCS7_KariGenerateEphemeralKey(kari, rng);
if (ret != 0) {
wc_PKCS7_KariFree(kari);
return ret;
}
/* generate KEK (key encryption key) */
ret = wc_PKCS7_KariGenerateKEK(kari, keyWrapAlgo, keyEncAlgo);
if (ret != 0) {
wc_PKCS7_KariFree(kari);
return ret;
}
/* encrypt CEK with KEK */
keySz = wc_PKCS7_KariKeyWrap(contentKeyPlain, blockKeySz, kari->kek,
kari->kekSz, contentKeyEnc, *keyEncSz, keyWrapAlgo,
direction);
if (keySz <= 0) {
wc_PKCS7_KariFree(kari);
return ret;
}
*keyEncSz = (word32)keySz;
/* Start of RecipientEncryptedKeys */
/* EncryptedKey */
encryptedKeyOctetSz = SetOctetString(*keyEncSz, encryptedKeyOctet);
totalSz += (encryptedKeyOctetSz + *keyEncSz);
/* SubjectKeyIdentifier */
subjKeyIdOctetSz = SetOctetString(KEYID_SIZE, subjKeyIdOctet);
totalSz += (subjKeyIdOctetSz + KEYID_SIZE);
/* RecipientKeyIdentifier IMPLICIT [0] */
recipKeyIdSeqSz = SetImplicit(ASN_SEQUENCE, 0, subjKeyIdOctetSz +
KEYID_SIZE, recipKeyIdSeq);
totalSz += recipKeyIdSeqSz;
/* RecipientEncryptedKey */
recipEncKeySeqSz = SetSequence(totalSz, recipEncKeySeq);
totalSz += recipEncKeySeqSz;
/* RecipientEncryptedKeys */
recipEncKeysSeqSz = SetSequence(totalSz, recipEncKeysSeq);
totalSz += recipEncKeysSeqSz;
/* Start of optional UserKeyingMaterial */
if (kari->ukmSz > 0) {
ukmOctetSz = SetOctetString(kari->ukmSz, ukmOctetStr);
totalSz += (ukmOctetSz + kari->ukmSz);
ukmExplicitSz = SetExplicit(1, ukmOctetSz + kari->ukmSz,
ukmExplicitSeq);
totalSz += ukmExplicitSz;
}
/* Start of KeyEncryptionAlgorithmIdentifier */
/* KeyWrapAlgorithm */
keyWrapAlgSz = SetAlgoID(keyWrapAlgo, keyWrapAlg, oidKeyWrapType, 0);
totalSz += keyWrapAlgSz;
/* KeyEncryptionAlgorithmIdentifier */
keyEncryptAlgoIdSz = SetAlgoID(keyEncAlgo, keyEncryptAlgoId,
oidCmsKeyAgreeType, keyWrapAlgSz);
totalSz += keyEncryptAlgoIdSz;
/* Start of OriginatorIdentifierOrKey */
/* recipient ECPoint, public key */
XMEMSET(origPubKeyStr, 0, sizeof(origPubKeyStr)); /* no unused bits */
origPubKeyStr[0] = ASN_BIT_STRING;
origPubKeyStrSz = SetLength(kari->senderKeyExportSz + 1,
origPubKeyStr + 1) + 2;
totalSz += (origPubKeyStrSz + kari->senderKeyExportSz);
/* Originator AlgorithmIdentifier */
origAlgIdSz = SetAlgoID(ECDSAk, origAlgId, oidKeyType, 0);
totalSz += origAlgIdSz;
/* outer OriginatorPublicKey IMPLICIT [1] */
origPubKeySeqSz = SetImplicit(ASN_SEQUENCE, 1,
origAlgIdSz + origPubKeyStrSz +
kari->senderKeyExportSz, origPubKeySeq);
totalSz += origPubKeySeqSz;
/* outer OriginatorIdentiferOrKey IMPLICIT [0] */
origIdOrKeySeqSz = SetImplicit(ASN_SEQUENCE, 0,
origPubKeySeqSz + origAlgIdSz +
origPubKeyStrSz + kari->senderKeyExportSz,
origIdOrKeySeq);
totalSz += origIdOrKeySeqSz;
/* version, always 3 */
verSz = SetMyVersion(3, ver, 0);
totalSz += verSz;
/* outer IMPLICIT [1] kari */
kariSeqSz = SetImplicit(ASN_SEQUENCE, 1, totalSz, kariSeq);
totalSz += kariSeqSz;
if ((word32)totalSz > outSz) {
WOLFSSL_MSG("KeyAgreeRecipientInfo output buffer too small");
wc_PKCS7_KariFree(kari);
return BUFFER_E;
}
XMEMCPY(out + idx, kariSeq, kariSeqSz);
idx += kariSeqSz;
XMEMCPY(out + idx, ver, verSz);
idx += verSz;
XMEMCPY(out + idx, origIdOrKeySeq, origIdOrKeySeqSz);
idx += origIdOrKeySeqSz;
XMEMCPY(out + idx, origPubKeySeq, origPubKeySeqSz);
idx += origPubKeySeqSz;
XMEMCPY(out + idx, origAlgId, origAlgIdSz);
idx += origAlgIdSz;
XMEMCPY(out + idx, origPubKeyStr, origPubKeyStrSz);
idx += origPubKeyStrSz;
/* ephemeral public key */
XMEMCPY(out + idx, kari->senderKeyExport, kari->senderKeyExportSz);
idx += kari->senderKeyExportSz;
if (kari->ukmSz > 0) {
XMEMCPY(out + idx, ukmExplicitSeq, ukmExplicitSz);
idx += ukmExplicitSz;
XMEMCPY(out + idx, ukmOctetStr, ukmOctetSz);
idx += ukmOctetSz;
XMEMCPY(out + idx, kari->ukm, kari->ukmSz);
idx += kari->ukmSz;
}
XMEMCPY(out + idx, keyEncryptAlgoId, keyEncryptAlgoIdSz);
idx += keyEncryptAlgoIdSz;
XMEMCPY(out + idx, keyWrapAlg, keyWrapAlgSz);
idx += keyWrapAlgSz;
XMEMCPY(out + idx, recipEncKeysSeq, recipEncKeysSeqSz);
idx += recipEncKeysSeqSz;
XMEMCPY(out + idx, recipEncKeySeq, recipEncKeySeqSz);
idx += recipEncKeySeqSz;
XMEMCPY(out + idx, recipKeyIdSeq, recipKeyIdSeqSz);
idx += recipKeyIdSeqSz;
XMEMCPY(out + idx, subjKeyIdOctet, subjKeyIdOctetSz);
idx += subjKeyIdOctetSz;
/* subject key id */
XMEMCPY(out + idx, kari->decoded->extSubjKeyId, KEYID_SIZE);
idx += KEYID_SIZE;
XMEMCPY(out + idx, encryptedKeyOctet, encryptedKeyOctetSz);
idx += encryptedKeyOctetSz;
/* encrypted CEK */
XMEMCPY(out + idx, contentKeyEnc, *keyEncSz);
idx += *keyEncSz;
wc_PKCS7_KariFree(kari);
return idx;
}
/* create ASN.1 formatted RecipientInfo structure, returns sequence size */
static int wc_CreateRecipientInfo(const byte* cert, word32 certSz,
int keyEncAlgo, int blockKeySz,
WC_RNG* rng, byte* contentKeyPlain,
byte* contentKeyEnc, int* keyEncSz,
byte* out, word32 outSz, void* heap)
{
word32 idx = 0;
int ret = 0, totalSz = 0;
int verSz, issuerSz, snSz, keyEncAlgSz;
int issuerSeqSz, recipSeqSz, issuerSerialSeqSz;
int encKeyOctetStrSz;
byte ver[MAX_VERSION_SZ];
byte issuerSerialSeq[MAX_SEQ_SZ];
byte recipSeq[MAX_SEQ_SZ];
byte issuerSeq[MAX_SEQ_SZ];
byte encKeyOctetStr[MAX_OCTET_STR_SZ];
#ifdef WOLFSSL_SMALL_STACK
byte *serial;
byte *keyAlgArray;
RsaKey* pubKey;
DecodedCert* decoded;
serial = (byte*)XMALLOC(MAX_SN_SZ, NULL, DYNAMIC_TYPE_TMP_BUFFER);
keyAlgArray = (byte*)XMALLOC(MAX_SN_SZ, NULL, DYNAMIC_TYPE_TMP_BUFFER);
decoded = (DecodedCert*)XMALLOC(sizeof(DecodedCert), NULL,
DYNAMIC_TYPE_TMP_BUFFER);
if (decoded == NULL || serial == NULL || keyAlgArray == NULL) {
if (serial) XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
if (keyAlgArray) XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
if (decoded) XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
return MEMORY_E;
}
#else
byte serial[MAX_SN_SZ];
byte keyAlgArray[MAX_ALGO_SZ];
RsaKey stack_pubKey;
RsaKey* pubKey = &stack_pubKey;
DecodedCert stack_decoded;
DecodedCert* decoded = &stack_decoded;
#endif
InitDecodedCert(decoded, (byte*)cert, certSz, heap);
ret = ParseCert(decoded, CA_TYPE, NO_VERIFY, 0);
if (ret < 0) {
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ret;
}
/* version */
verSz = SetMyVersion(0, ver, 0);
/* IssuerAndSerialNumber */
if (decoded->issuerRaw == NULL || decoded->issuerRawLen == 0) {
WOLFSSL_MSG("DecodedCert lacks raw issuer pointer and length");
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return -1;
}
issuerSz = decoded->issuerRawLen;
issuerSeqSz = SetSequence(issuerSz, issuerSeq);
if (decoded->serialSz == 0) {
WOLFSSL_MSG("DecodedCert missing serial number");
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return -1;
}
snSz = SetSerialNumber(decoded->serial, decoded->serialSz, serial);
issuerSerialSeqSz = SetSequence(issuerSeqSz + issuerSz + snSz,
issuerSerialSeq);
/* KeyEncryptionAlgorithmIdentifier, only support RSA now */
if (keyEncAlgo != RSAk) {
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ALGO_ID_E;
}
keyEncAlgSz = SetAlgoID(keyEncAlgo, keyAlgArray, oidKeyType, 0);
if (keyEncAlgSz == 0) {
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return BAD_FUNC_ARG;
}
#ifdef WOLFSSL_SMALL_STACK
pubKey = (RsaKey*)XMALLOC(sizeof(RsaKey), NULL, DYNAMIC_TYPE_TMP_BUFFER);
if (pubKey == NULL) {
FreeDecodedCert(decoded);
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
return MEMORY_E;
}
#endif
/* EncryptedKey */
ret = wc_InitRsaKey(pubKey, 0);
if (ret != 0) {
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(pubKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ret;
}
if (wc_RsaPublicKeyDecode(decoded->publicKey, &idx, pubKey,
decoded->pubKeySize) < 0) {
WOLFSSL_MSG("ASN RSA key decode error");
wc_FreeRsaKey(pubKey);
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(pubKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return PUBLIC_KEY_E;
}
*keyEncSz = wc_RsaPublicEncrypt(contentKeyPlain, blockKeySz, contentKeyEnc,
MAX_ENCRYPTED_KEY_SZ, pubKey, rng);
wc_FreeRsaKey(pubKey);
#ifdef WOLFSSL_SMALL_STACK
XFREE(pubKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
if (*keyEncSz < 0) {
WOLFSSL_MSG("RSA Public Encrypt failed");
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return *keyEncSz;
}
encKeyOctetStrSz = SetOctetString(*keyEncSz, encKeyOctetStr);
/* RecipientInfo */
recipSeqSz = SetSequence(verSz + issuerSerialSeqSz + issuerSeqSz +
issuerSz + snSz + keyEncAlgSz + encKeyOctetStrSz +
*keyEncSz, recipSeq);
if (recipSeqSz + verSz + issuerSerialSeqSz + issuerSeqSz + snSz +
keyEncAlgSz + encKeyOctetStrSz + *keyEncSz > (int)outSz) {
WOLFSSL_MSG("RecipientInfo output buffer too small");
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return BUFFER_E;
}
XMEMCPY(out + totalSz, recipSeq, recipSeqSz);
totalSz += recipSeqSz;
XMEMCPY(out + totalSz, ver, verSz);
totalSz += verSz;
XMEMCPY(out + totalSz, issuerSerialSeq, issuerSerialSeqSz);
totalSz += issuerSerialSeqSz;
XMEMCPY(out + totalSz, issuerSeq, issuerSeqSz);
totalSz += issuerSeqSz;
XMEMCPY(out + totalSz, decoded->issuerRaw, issuerSz);
totalSz += issuerSz;
XMEMCPY(out + totalSz, serial, snSz);
totalSz += snSz;
XMEMCPY(out + totalSz, keyAlgArray, keyEncAlgSz);
totalSz += keyEncAlgSz;
XMEMCPY(out + totalSz, encKeyOctetStr, encKeyOctetStrSz);
totalSz += encKeyOctetStrSz;
XMEMCPY(out + totalSz, contentKeyEnc, *keyEncSz);
totalSz += *keyEncSz;
FreeDecodedCert(decoded);
#ifdef WOLFSSL_SMALL_STACK
XFREE(serial, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(keyAlgArray, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(decoded, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return totalSz;
}
/* encrypt content using encryptOID algo */
static int wc_PKCS7_EncryptContent(int encryptOID, byte* key, int keySz,
byte* iv, int ivSz, byte* in, int inSz,
byte* out)
{
int ret;
#ifndef NO_AES
Aes aes;
#endif
#ifndef NO_DES3
Des des;
Des3 des3;
#endif
if (key == NULL || iv == NULL || in == NULL || out == NULL)
return BAD_FUNC_ARG;
switch (encryptOID) {
#ifndef NO_AES
case AES128CBCb:
case AES192CBCb:
case AES256CBCb:
if ( (encryptOID == AES128CBCb && keySz != 16 ) ||
(encryptOID == AES192CBCb && keySz != 24 ) ||
(encryptOID == AES256CBCb && keySz != 32 ) ||
(ivSz != AES_BLOCK_SIZE) )
return BAD_FUNC_ARG;
ret = wc_AesSetKey(&aes, key, keySz, iv, AES_ENCRYPTION);
if (ret == 0)
ret = wc_AesCbcEncrypt(&aes, out, in, inSz);
break;
#endif
#ifndef NO_DES3
case DESb:
if (keySz != DES_KEYLEN || ivSz != DES_BLOCK_SIZE)
return BAD_FUNC_ARG;
ret = wc_Des_SetKey(&des, key, iv, DES_ENCRYPTION);
if (ret == 0)
ret = wc_Des_CbcEncrypt(&des, out, in, inSz);
break;
case DES3b:
if (keySz != DES3_KEYLEN || ivSz != DES_BLOCK_SIZE)
return BAD_FUNC_ARG;
ret = wc_Des3_SetKey(&des3, key, iv, DES_ENCRYPTION);
if (ret == 0)
ret = wc_Des3_CbcEncrypt(&des3, out, in, inSz);
break;
#endif
default:
WOLFSSL_MSG("Unsupported content cipher type");
return ALGO_ID_E;
};
return ret;
}
/* decrypt content using encryptOID algo */
static int wc_PKCS7_DecryptContent(int encryptOID, byte* key, int keySz,
byte* iv, int ivSz, byte* in, int inSz,
byte* out)
{
int ret;
#ifndef NO_AES
Aes aes;
#endif
#ifndef NO_DES3
Des des;
Des3 des3;
#endif
if (key == NULL || iv == NULL || in == NULL || out == NULL)
return BAD_FUNC_ARG;
switch (encryptOID) {
#ifndef NO_AES
case AES128CBCb:
case AES192CBCb:
case AES256CBCb:
if ( (encryptOID == AES128CBCb && keySz != 16 ) ||
(encryptOID == AES192CBCb && keySz != 24 ) ||
(encryptOID == AES256CBCb && keySz != 32 ) ||
(ivSz != AES_BLOCK_SIZE) )
return BAD_FUNC_ARG;
ret = wc_AesSetKey(&aes, key, keySz, iv, AES_DECRYPTION);
if (ret == 0)
ret = wc_AesCbcDecrypt(&aes, out, in, inSz);
break;
#endif
#ifndef NO_DES3
case DESb:
if (keySz != DES_KEYLEN || ivSz != DES_BLOCK_SIZE)
return BAD_FUNC_ARG;
ret = wc_Des_SetKey(&des, key, iv, DES_DECRYPTION);
if (ret == 0)
ret = wc_Des_CbcDecrypt(&des, out, in, inSz);
break;
case DES3b:
if (keySz != DES3_KEYLEN || ivSz != DES_BLOCK_SIZE)
return BAD_FUNC_ARG;
ret = wc_Des3_SetKey(&des3, key, iv, DES_DECRYPTION);
if (ret == 0)
ret = wc_Des3_CbcDecrypt(&des3, out, in, inSz);
break;
#endif
default:
WOLFSSL_MSG("Unsupported content cipher type");
return ALGO_ID_E;
};
return ret;
}
/* generate random IV, place in iv, return 0 on success negative on error */
static int wc_PKCS7_GenerateIV(WC_RNG* rng, byte* iv, word32 ivSz)
{
int ret;
WC_RNG* random = NULL;
if (iv == NULL || ivSz == 0)
return BAD_FUNC_ARG;
/* input RNG is optional, init local one if input rng is NULL */
if (rng == NULL) {
random = (WC_RNG*)XMALLOC(sizeof(WC_RNG), NULL, DYNAMIC_TYPE_RNG);
if (random == NULL)
return MEMORY_E;
ret = wc_InitRng(random);
if (ret != 0) {
XFREE(random, NULL, DYNAMIC_TYPE_RNG);
return ret;
}
} else {
random = rng;
}
ret = wc_RNG_GenerateBlock(random, iv, ivSz);
if (rng == NULL) {
wc_FreeRng(random);
XFREE(random, NULL, DYNAMIC_TYPE_RNG);
}
return ret;
}
/* return size of padded data, padded to blockSz chunks, or negative on error */
static int wc_PKCS7_GetPadSize(word32 inputSz, word32 blockSz)
{
int padSz;
if (blockSz == 0)
return BAD_FUNC_ARG;
padSz = blockSz - (inputSz % blockSz);
return padSz;
}
/* pad input data to blockSz chunk, place in outSz. out must be big enough
* for input + pad bytes. See wc_PKCS7_GetPadLength() helper. */
static int wc_PKCS7_PadData(byte* in, word32 inSz, byte* out, word32 outSz,
word32 blockSz)
{
int i, padSz;
if (in == NULL || inSz == 0 ||
out == NULL || outSz == 0)
return BAD_FUNC_ARG;
padSz = blockSz - (inSz % blockSz);
if (outSz < (inSz + padSz))
return BAD_FUNC_ARG;
XMEMCPY(out, in, inSz);
for (i = 0; i < padSz; i++) {
out[inSz + i] = (byte)padSz;
}
return inSz + padSz;
}
/* build PKCS#7 envelopedData content type, return enveloped size */
int wc_PKCS7_EncodeEnvelopedData(PKCS7* pkcs7, byte* output, word32 outputSz)
{
int ret, idx = 0;
int totalSz, padSz, encryptedOutSz;
int contentInfoSeqSz, outerContentTypeSz, outerContentSz;
byte contentInfoSeq[MAX_SEQ_SZ];
byte outerContentType[MAX_ALGO_SZ];
byte outerContent[MAX_SEQ_SZ];
int envDataSeqSz, verSz;
byte envDataSeq[MAX_SEQ_SZ];
byte ver[MAX_VERSION_SZ];
WC_RNG rng;
int contentKeyEncSz, blockSz, blockKeySz;
byte contentKeyPlain[MAX_CONTENT_KEY_LEN];
#ifdef WOLFSSL_SMALL_STACK
byte* contentKeyEnc;
#else
byte contentKeyEnc[MAX_ENCRYPTED_KEY_SZ];
#endif
byte* plain;
byte* encryptedContent;
int recipSz, recipSetSz;
#ifdef WOLFSSL_SMALL_STACK
byte* recip;
#else
byte recip[MAX_RECIP_SZ];
#endif
byte recipSet[MAX_SET_SZ];
int encContentOctetSz, encContentSeqSz, contentTypeSz;
int contentEncAlgoSz, ivOctetStringSz;
byte encContentSeq[MAX_SEQ_SZ];
byte contentType[MAX_ALGO_SZ];
byte contentEncAlgo[MAX_ALGO_SZ];
byte tmpIv[MAX_CONTENT_IV_SIZE];
byte ivOctetString[MAX_OCTET_STR_SZ];
byte encContentOctet[MAX_OCTET_STR_SZ];
if (pkcs7 == NULL || pkcs7->content == NULL || pkcs7->contentSz == 0 ||
pkcs7->encryptOID == 0 || pkcs7->singleCert == NULL ||
pkcs7->publicKeyOID == 0)
return BAD_FUNC_ARG;
if (output == NULL || outputSz == 0)
return BAD_FUNC_ARG;
blockKeySz = wc_PKCS7_GetOIDKeySize(pkcs7->encryptOID);
if (blockKeySz < 0)
return blockKeySz;
blockSz = wc_PKCS7_GetOIDBlockSize(pkcs7->encryptOID);
if (blockSz < 0)
return blockSz;
/* outer content type */
outerContentTypeSz = wc_SetContentType(ENVELOPED_DATA, outerContentType);
/* version, defined as 0 in RFC 2315 */
if (pkcs7->publicKeyOID == ECDSAk) {
verSz = SetMyVersion(2, ver, 0);
} else {
verSz = SetMyVersion(0, ver, 0);
}
/* generate random content encryption key */
ret = wc_InitRng_ex(&rng, pkcs7->heap);
if (ret != 0)
return ret;
ret = wc_RNG_GenerateBlock(&rng, contentKeyPlain, blockKeySz);
if (ret != 0) {
wc_FreeRng(&rng);
return ret;
}
#ifdef WOLFSSL_SMALL_STACK
recip = (byte*)XMALLOC(MAX_RECIP_SZ, NULL, DYNAMIC_TYPE_PKCS7);
contentKeyEnc = (byte*)XMALLOC(MAX_ENCRYPTED_KEY_SZ, NULL,
DYNAMIC_TYPE_PKCS7);
if (contentKeyEnc == NULL || recip == NULL) {
if (recip) XFREE(recip, NULL, DYNAMIC_TYPE_PKCS7);
if (contentKeyEnc) XFREE(contentKeyEnc, NULL, DYNAMIC_TYPE_PKCS7);
wc_FreeRng(&rng);
return MEMORY_E;
}
#endif
contentKeyEncSz = MAX_ENCRYPTED_KEY_SZ;
/* build RecipientInfo, only handle 1 for now */
switch (pkcs7->publicKeyOID) {
case RSAk:
recipSz = wc_CreateRecipientInfo(pkcs7->singleCert,
pkcs7->singleCertSz,
pkcs7->publicKeyOID,
blockKeySz, &rng, contentKeyPlain,
contentKeyEnc, &contentKeyEncSz, recip,
MAX_RECIP_SZ, pkcs7->heap);
break;
case ECDSAk:
recipSz = wc_CreateKeyAgreeRecipientInfo(pkcs7, pkcs7->singleCert,
pkcs7->singleCertSz,
pkcs7->publicKeyOID,
blockKeySz, pkcs7->keyWrapOID,
pkcs7->keyAgreeOID, &rng,
contentKeyPlain, contentKeyEnc,
&contentKeyEncSz, recip, MAX_RECIP_SZ);
break;
default:
WOLFSSL_MSG("Unsupported RecipientInfo public key type");
return BAD_FUNC_ARG;
};
ForceZero(contentKeyEnc, MAX_ENCRYPTED_KEY_SZ);
#ifdef WOLFSSL_SMALL_STACK
XFREE(contentKeyEnc, NULL, DYNAMIC_TYPE_PKCS7);
#endif
if (recipSz < 0) {
WOLFSSL_MSG("Failed to create RecipientInfo");
wc_FreeRng(&rng);
#ifdef WOLFSSL_SMALL_STACK
XFREE(recip, NULL, DYNAMMIC_TYPE_TMP_BUFFER);
#endif
return recipSz;
}
recipSetSz = SetSet(recipSz, recipSet);
/* generate IV for block cipher */
ret = wc_PKCS7_GenerateIV(&rng, tmpIv, blockSz);
wc_FreeRng(&rng);
if (ret != 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(recip, NULL, DYNAMMIC_TYPE_TMP_BUFFER);
#endif
return ret;
}
/* EncryptedContentInfo */
contentTypeSz = wc_SetContentType(pkcs7->contentOID, contentType);
if (contentTypeSz == 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(recip, NULL, DYNAMMIC_TYPE_TMP_BUFFER);
#endif
return BAD_FUNC_ARG;
}
/* allocate encrypted content buffer and PKCS#7 padding */
padSz = wc_PKCS7_GetPadSize(pkcs7->contentSz, blockSz);
if (padSz < 0)
return padSz;
encryptedOutSz = pkcs7->contentSz + padSz;
plain = (byte*)XMALLOC(encryptedOutSz, pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (plain == NULL)
return MEMORY_E;
ret = wc_PKCS7_PadData(pkcs7->content, pkcs7->contentSz, plain,
encryptedOutSz, blockSz);
if (ret < 0) {
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return ret;
}
encryptedContent = (byte*)XMALLOC(encryptedOutSz, pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (encryptedContent == NULL) {
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
#ifdef WOLFSSL_SMALL_STACK
XFREE(recip, NULL, DYNAMMIC_TYPE_TMP_BUFFER);
#endif
return MEMORY_E;
}
/* put together IV OCTET STRING */
ivOctetStringSz = SetOctetString(blockSz, ivOctetString);
/* build up our ContentEncryptionAlgorithmIdentifier sequence,
* adding (ivOctetStringSz + blockSz) for IV OCTET STRING */
contentEncAlgoSz = SetAlgoID(pkcs7->encryptOID, contentEncAlgo,
oidBlkType, ivOctetStringSz + blockSz);
if (contentEncAlgoSz == 0) {
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
#ifdef WOLFSSL_SMALL_STACK
XFREE(recip, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return BAD_FUNC_ARG;
}
/* encrypt content */
ret = wc_PKCS7_EncryptContent(pkcs7->encryptOID, contentKeyPlain,
blockKeySz, tmpIv, blockSz, plain, encryptedOutSz,
encryptedContent);
if (ret != 0) {
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
#ifdef WOLFSSL_SMALL_STACK
XFREE(recip, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ret;
}
encContentOctetSz = SetImplicit(ASN_OCTET_STRING, 0, encryptedOutSz,
encContentOctet);
encContentSeqSz = SetSequence(contentTypeSz + contentEncAlgoSz +
ivOctetStringSz + blockSz +
encContentOctetSz + encryptedOutSz,
encContentSeq);
/* keep track of sizes for outer wrapper layering */
totalSz = verSz + recipSetSz + recipSz + encContentSeqSz + contentTypeSz +
contentEncAlgoSz + ivOctetStringSz + blockSz +
encContentOctetSz + encryptedOutSz;
/* EnvelopedData */
envDataSeqSz = SetSequence(totalSz, envDataSeq);
totalSz += envDataSeqSz;
/* outer content */
outerContentSz = SetExplicit(0, totalSz, outerContent);
totalSz += outerContentTypeSz;
totalSz += outerContentSz;
/* ContentInfo */
contentInfoSeqSz = SetSequence(totalSz, contentInfoSeq);
totalSz += contentInfoSeqSz;
if (totalSz > (int)outputSz) {
WOLFSSL_MSG("Pkcs7_encrypt output buffer too small");
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_TMP_BUFFER);
#ifdef WOLFSSL_SMALL_STACK
XFREE(recip, NULL, DYNAMMIC_TYPE_TMP_BUFFER);
#endif
return BUFFER_E;
}
XMEMCPY(output + idx, contentInfoSeq, contentInfoSeqSz);
idx += contentInfoSeqSz;
XMEMCPY(output + idx, outerContentType, outerContentTypeSz);
idx += outerContentTypeSz;
XMEMCPY(output + idx, outerContent, outerContentSz);
idx += outerContentSz;
XMEMCPY(output + idx, envDataSeq, envDataSeqSz);
idx += envDataSeqSz;
XMEMCPY(output + idx, ver, verSz);
idx += verSz;
XMEMCPY(output + idx, recipSet, recipSetSz);
idx += recipSetSz;
XMEMCPY(output + idx, recip, recipSz);
idx += recipSz;
XMEMCPY(output + idx, encContentSeq, encContentSeqSz);
idx += encContentSeqSz;
XMEMCPY(output + idx, contentType, contentTypeSz);
idx += contentTypeSz;
XMEMCPY(output + idx, contentEncAlgo, contentEncAlgoSz);
idx += contentEncAlgoSz;
XMEMCPY(output + idx, ivOctetString, ivOctetStringSz);
idx += ivOctetStringSz;
XMEMCPY(output + idx, tmpIv, blockSz);
idx += blockSz;
XMEMCPY(output + idx, encContentOctet, encContentOctetSz);
idx += encContentOctetSz;
XMEMCPY(output + idx, encryptedContent, encryptedOutSz);
idx += encryptedOutSz;
ForceZero(contentKeyPlain, MAX_CONTENT_KEY_LEN);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
#ifdef WOLFSSL_SMALL_STACK
XFREE(recip, NULL, DYNAMMIC_TYPE_TMP_BUFFER);
#endif
return idx;
}
/* decode KeyTransRecipientInfo (ktri), return 0 on success, <0 on error */
static int wc_PKCS7_DecodeKtri(PKCS7* pkcs7, byte* pkiMsg, word32 pkiMsgSz,
word32* idx, byte* decryptedKey,
word32* decryptedKeySz, int* recipFound)
{
int length, encryptedKeySz, ret;
int keySz;
word32 encOID;
word32 keyIdx;
byte issuerHash[SHA_DIGEST_SIZE];
byte* outKey = NULL;
#ifdef WC_RSA_BLINDING
WC_RNG rng;
#endif
#ifdef WOLFSSL_SMALL_STACK
mp_int* serialNum;
byte* encryptedKey;
RsaKey* privKey;
#else
mp_int stack_serialNum;
mp_int* serialNum = &stack_serialNum;
byte encryptedKey[MAX_ENCRYPTED_KEY_SZ];
RsaKey stack_privKey;
RsaKey* privKey = &stack_privKey;
#endif
/* remove IssuerAndSerialNumber */
if (GetSequence(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (GetNameHash(pkiMsg, idx, issuerHash, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* if we found correct recipient, issuer hashes will match */
if (XMEMCMP(issuerHash, pkcs7->issuerHash, SHA_DIGEST_SIZE) == 0) {
*recipFound = 1;
}
#ifdef WOLFSSL_SMALL_STACK
serialNum = (mp_int*)XMALLOC(sizeof(mp_int), NULL,
DYNAMIC_TYPE_TMP_BUFFER);
if (serialNum == NULL)
return MEMORY_E;
#endif
if (GetInt(serialNum, pkiMsg, idx, pkiMsgSz) < 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(serialNum, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ASN_PARSE_E;
}
mp_clear(serialNum);
#ifdef WOLFSSL_SMALL_STACK
XFREE(serialNum, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
if (GetAlgoId(pkiMsg, idx, &encOID, oidKeyType, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* key encryption algorithm must be RSA for now */
if (encOID != RSAk)
return ALGO_ID_E;
/* read encryptedKey */
#ifdef WOLFSSL_SMALL_STACK
encryptedKey = (byte*)XMALLOC(MAX_ENCRYPTED_KEY_SZ, NULL,
DYNAMIC_TYPE_TMP_BUFFER);
if (encryptedKey == NULL)
return MEMORY_E;
#endif
if (pkiMsg[(*idx)++] != ASN_OCTET_STRING) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ASN_PARSE_E;
}
if (GetLength(pkiMsg, idx, &encryptedKeySz, pkiMsgSz) < 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ASN_PARSE_E;
}
if (*recipFound == 1)
XMEMCPY(encryptedKey, &pkiMsg[*idx], encryptedKeySz);
*idx += encryptedKeySz;
/* load private key */
#ifdef WOLFSSL_SMALL_STACK
privKey = (RsaKey*)XMALLOC(sizeof(RsaKey), NULL, DYNAMIC_TYPE_TMP_BUFFER);
if (privKey == NULL) {
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
return MEMORY_E;
}
#endif
ret = wc_InitRsaKey(privKey, 0);
if (ret != 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(privKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ret;
}
keyIdx = 0;
ret = wc_RsaPrivateKeyDecode(pkcs7->privateKey, &keyIdx, privKey,
pkcs7->privateKeySz);
if (ret != 0) {
WOLFSSL_MSG("Failed to decode RSA private key");
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(privKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return ret;
}
/* decrypt encryptedKey */
#ifdef WC_RSA_BLINDING
ret = wc_InitRng(&rng);
if (ret == 0) {
ret = wc_RsaSetRNG(privKey, &rng);
}
#endif
if (ret == 0) {
keySz = wc_RsaPrivateDecryptInline(encryptedKey, encryptedKeySz,
&outKey, privKey);
#ifdef WC_RSA_BLINDING
wc_FreeRng(&rng);
#endif
} else {
keySz = ret;
}
wc_FreeRsaKey(privKey);
if (keySz <= 0 || outKey == NULL) {
ForceZero(encryptedKey, MAX_ENCRYPTED_KEY_SZ);
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(privKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return keySz;
} else {
*decryptedKeySz = keySz;
XMEMCPY(decryptedKey, outKey, keySz);
ForceZero(encryptedKey, MAX_ENCRYPTED_KEY_SZ);
}
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
XFREE(privKey, NULL, DYNAMIC_TYPE_TMP_BUFFER);
#endif
return 0;
}
/* remove ASN.1 OriginatorIdentifierOrKey, return 0 on success, <0 on error */
static int wc_PKCS7_KariGetOriginatorIdentifierOrKey(WC_PKCS7_KARI* kari,
byte* pkiMsg, word32 pkiMsgSz, word32* idx)
{
int ret, length;
word32 keyOID;
if (kari == NULL || pkiMsg == NULL || idx == NULL)
return BAD_FUNC_ARG;
/* remove OriginatorIdentifierOrKey */
if (pkiMsg[*idx] == (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 0)) {
(*idx)++;
if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
} else {
return ASN_PARSE_E;
}
/* remove OriginatorPublicKey */
if (pkiMsg[*idx] == (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 1)) {
(*idx)++;
if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
} else {
return ASN_PARSE_E;
}
/* remove AlgorithmIdentifier */
if (GetAlgoId(pkiMsg, idx, &keyOID, oidKeyType, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (keyOID != ECDSAk)
return ASN_PARSE_E;
/* remove ECPoint BIT STRING */
if ((pkiMsgSz > (*idx + 1)) && (pkiMsg[(*idx)++] != ASN_BIT_STRING))
return ASN_PARSE_E;
if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if ((pkiMsgSz < (*idx + 1)) || (pkiMsg[(*idx)++] != 0x00))
return ASN_EXPECT_0_E;
/* get sender ephemeral public ECDSA key */
ret = wc_ecc_init(kari->senderKey);
if (ret != 0)
return ret;
/* length-1 for unused bits counter */
ret = wc_ecc_import_x963(pkiMsg + (*idx), length - 1, kari->senderKey);
if (ret != 0)
return ret;
(*idx) += length - 1;
return 0;
}
/* remove optional UserKeyingMaterial if available, return 0 on success,
* < 0 on error */
static int wc_PKCS7_KariGetUserKeyingMaterial(WC_PKCS7_KARI* kari,
byte* pkiMsg, word32 pkiMsgSz, word32* idx)
{
int length;
word32 savedIdx;
if (kari == NULL || pkiMsg == NULL || idx == NULL)
return BAD_FUNC_ARG;
savedIdx = *idx;
/* starts with EXPLICIT [1] */
if (pkiMsg[(*idx)++] != (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 1)) {
*idx = savedIdx;
return 0;
}
if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0) {
*idx = savedIdx;
return 0;
}
/* get OCTET STRING */
if ( (pkiMsgSz > ((*idx) + 1)) &&
(pkiMsg[(*idx)++] != ASN_OCTET_STRING) ) {
*idx = savedIdx;
return 0;
}
if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0) {
*idx = savedIdx;
return 0;
}
kari->ukm = NULL;
if (length > 0) {
kari->ukm = (byte*)XMALLOC(length, kari->heap, DYNAMIC_TYPE_PKCS7);
if (kari->ukm == NULL)
return MEMORY_E;
XMEMCPY(kari->ukm, pkiMsg + (*idx), length);
kari->ukmOwner = 1;
}
(*idx) += length;
kari->ukmSz = length;
return 0;
}
/* remove ASN.1 KeyEncryptionAlgorithmIdentifier, return 0 on success,
* < 0 on error */
static int wc_PKCS7_KariGetKeyEncryptionAlgorithmId(WC_PKCS7_KARI* kari,
byte* pkiMsg, word32 pkiMsgSz, word32* idx,
word32* keyAgreeOID, word32* keyWrapOID)
{
if (kari == NULL || pkiMsg == NULL || idx == NULL ||
keyAgreeOID == NULL || keyWrapOID == NULL)
return BAD_FUNC_ARG;
/* remove KeyEncryptionAlgorithmIdentifier */
if (GetAlgoId(pkiMsg, idx, keyAgreeOID, oidCmsKeyAgreeType,
pkiMsgSz) < 0)
return ASN_PARSE_E;
/* remove KeyWrapAlgorithm, stored in parameter of KeyEncAlgoId */
if (GetAlgoId(pkiMsg, idx, keyWrapOID, oidKeyWrapType, pkiMsgSz) < 0)
return ASN_PARSE_E;
return 0;
}
/* remove ASN.1 RecipientEncryptedKeys, return 0 on success, < 0 on error */
static int wc_PKCS7_KariGetRecipientEncryptedKeys(WC_PKCS7_KARI* kari,
byte* pkiMsg, word32 pkiMsgSz, word32* idx,
int* recipFound, byte* encryptedKey,
int* encryptedKeySz)
{
int length;
byte subjKeyId[KEYID_SIZE];
if (kari == NULL || pkiMsg == NULL || idx == NULL ||
recipFound == NULL || encryptedKey == NULL)
return BAD_FUNC_ARG;
/* remove RecipientEncryptedKeys */
if (GetSequence(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* remove RecipientEncryptedKeys */
if (GetSequence(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* remove RecipientKeyIdentifier IMPLICIT [0] */
if ( (pkiMsgSz > (*idx + 1)) &&
(pkiMsg[(*idx)++] == (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 0)) ) {
if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
} else {
return ASN_PARSE_E;
}
/* remove SubjectKeyIdentifier */
if ( (pkiMsgSz > (*idx + 1)) &&
(pkiMsg[(*idx)++] != ASN_OCTET_STRING) )
return ASN_PARSE_E;
if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (length != KEYID_SIZE)
return ASN_PARSE_E;
XMEMCPY(subjKeyId, pkiMsg + (*idx), KEYID_SIZE);
(*idx) += length;
/* subject key id should match if recipient found */
if (XMEMCMP(subjKeyId, kari->decoded->extSubjKeyId, KEYID_SIZE) == 0) {
*recipFound = 1;
}
/* remove EncryptedKey */
if ( (pkiMsgSz > (*idx + 1)) &&
(pkiMsg[(*idx)++] != ASN_OCTET_STRING) )
return ASN_PARSE_E;
if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* put encrypted CEK in decryptedKey buffer for now, decrypt later */
if (length > *encryptedKeySz)
return BUFFER_E;
XMEMCPY(encryptedKey, pkiMsg + (*idx), length);
*encryptedKeySz = length;
(*idx) += length;
return 0;
}
/* decode ASN.1 KeyAgreeRecipientInfo (kari), return 0 on success,
* < 0 on error */
static int wc_PKCS7_DecodeKari(PKCS7* pkcs7, byte* pkiMsg, word32 pkiMsgSz,
word32* idx, byte* decryptedKey,
word32* decryptedKeySz, int* recipFound)
{
int ret, keySz;
int encryptedKeySz;
int direction = 0;
word32 keyAgreeOID, keyWrapOID;
#ifdef WOLFSSL_SMALL_STACK
byte* encryptedKey;
#else
byte encryptedKey[MAX_ENCRYPTED_KEY_SZ];
#endif
WC_PKCS7_KARI* kari;
if (pkcs7 == NULL || pkcs7->singleCert == NULL ||
pkcs7->singleCertSz == 0 || pkiMsg == NULL ||
idx == NULL || decryptedKey == NULL || decryptedKeySz == NULL) {
return BAD_FUNC_ARG;
}
kari = wc_PKCS7_KariNew(pkcs7, WC_PKCS7_DECODE);
if (kari == NULL)
return MEMORY_E;
#ifdef WOLFSSL_SMALL_STACK
encryptedKey = (byte*)XMALLOC(MAX_ENCRYPTED_KEY_SZ, NULL,
DYNAMIC_TYPE_PKCS7);
if (encryptedKey == NULL) {
wc_PKCS7_KariFree(kari);
return MEMORY_E;
}
#endif
encryptedKeySz = MAX_ENCRYPTED_KEY_SZ;
/* parse cert and key */
ret = wc_PKCS7_KariParseRecipCert(kari, (byte*)pkcs7->singleCert,
pkcs7->singleCertSz, pkcs7->privateKey,
pkcs7->privateKeySz);
if (ret != 0) {
wc_PKCS7_KariFree(kari);
return ret;
}
/* remove OriginatorIdentifierOrKey */
ret = wc_PKCS7_KariGetOriginatorIdentifierOrKey(kari, pkiMsg,
pkiMsgSz, idx);
if (ret != 0) {
wc_PKCS7_KariFree(kari);
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ret;
}
/* try and remove optional UserKeyingMaterial */
ret = wc_PKCS7_KariGetUserKeyingMaterial(kari, pkiMsg, pkiMsgSz, idx);
if (ret != 0) {
wc_PKCS7_KariFree(kari);
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ret;
}
/* remove KeyEncryptionAlgorithmIdentifier */
ret = wc_PKCS7_KariGetKeyEncryptionAlgorithmId(kari, pkiMsg, pkiMsgSz,
idx, &keyAgreeOID,
&keyWrapOID);
if (ret != 0) {
wc_PKCS7_KariFree(kari);
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ret;
}
/* set direction based on key wrap algorithm */
switch (keyWrapOID) {
#ifndef NO_AES
case AES128_WRAP:
case AES192_WRAP:
case AES256_WRAP:
direction = AES_DECRYPTION;
break;
#endif
default:
wc_PKCS7_KariFree(kari);
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
WOLFSSL_MSG("AES key wrap algorithm unsupported");
return BAD_KEYWRAP_ALG_E;
}
/* remove RecipientEncryptedKeys */
ret = wc_PKCS7_KariGetRecipientEncryptedKeys(kari, pkiMsg, pkiMsgSz,
idx, recipFound, encryptedKey, &encryptedKeySz);
if (ret != 0) {
wc_PKCS7_KariFree(kari);
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ret;
}
/* create KEK */
ret = wc_PKCS7_KariGenerateKEK(kari, keyWrapOID, pkcs7->keyAgreeOID);
if (ret != 0) {
wc_PKCS7_KariFree(kari);
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ret;
}
/* decrypt CEK with KEK */
keySz = wc_PKCS7_KariKeyWrap(encryptedKey, encryptedKeySz, kari->kek,
kari->kekSz, decryptedKey, *decryptedKeySz,
keyWrapOID, direction);
if (keySz <= 0) {
wc_PKCS7_KariFree(kari);
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return keySz;
}
*decryptedKeySz = (word32)keySz;
wc_PKCS7_KariFree(kari);
#ifdef WOLFSSL_SMALL_STACK
XFREE(encryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return 0;
}
/* decode ASN.1 RecipientInfos SET, return 0 on success, < 0 on error */
static int wc_PKCS7_DecodeRecipientInfos(PKCS7* pkcs7, byte* pkiMsg,
word32 pkiMsgSz, word32* idx, byte* decryptedKey,
word32* decryptedKeySz, int* recipFound)
{
word32 savedIdx;
int version, ret, length;
if (pkcs7 == NULL || pkiMsg == NULL || idx == NULL ||
decryptedKey == NULL || decryptedKeySz == NULL ||
recipFound == NULL) {
return BAD_FUNC_ARG;
}
savedIdx = *idx;
/* when looking for next recipient, use first sequence and version to
* indicate there is another, if not, move on */
while(*recipFound == 0) {
/* remove RecipientInfo, if we don't have a SEQUENCE, back up idx to
* last good saved one */
if (GetSequence(pkiMsg, idx, &length, pkiMsgSz) > 0) {
if (GetMyVersion(pkiMsg, idx, &version, pkiMsgSz) < 0) {
*idx = savedIdx;
break;
}
if (version != 0)
return ASN_VERSION_E;
/* found ktri */
ret = wc_PKCS7_DecodeKtri(pkcs7, pkiMsg, pkiMsgSz, idx,
decryptedKey, decryptedKeySz,
recipFound);
if (ret != 0)
return ret;
}
else {
/* kari is IMPLICIT[1] */
*idx = savedIdx;
if (pkiMsg[*idx] == (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 1)) {
(*idx)++;
if (GetLength(pkiMsg, idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (GetMyVersion(pkiMsg, idx, &version, pkiMsgSz) < 0) {
*idx = savedIdx;
break;
}
if (version != 3)
return ASN_VERSION_E;
/* found kari */
ret = wc_PKCS7_DecodeKari(pkcs7, pkiMsg, pkiMsgSz, idx,
decryptedKey, decryptedKeySz,
recipFound);
if (ret != 0)
return ret;
}
else {
/* failed to find RecipientInfo, restore idx and continue */
*idx = savedIdx;
break;
}
}
/* update good idx */
savedIdx = *idx;
}
return 0;
}
/* unwrap and decrypt PKCS#7 envelopedData object, return decoded size */
WOLFSSL_API int wc_PKCS7_DecodeEnvelopedData(PKCS7* pkcs7, byte* pkiMsg,
word32 pkiMsgSz, byte* output,
word32 outputSz)
{
int recipFound = 0;
int ret, version, length;
word32 idx = 0;
word32 contentType, encOID;
word32 decryptedKeySz;
int expBlockSz, blockKeySz;
byte tmpIv[MAX_CONTENT_IV_SIZE];
#ifdef WOLFSSL_SMALL_STACK
byte* decryptedKey;
#else
byte decryptedKey[MAX_ENCRYPTED_KEY_SZ];
#endif
int encryptedContentSz;
byte padLen;
byte* encryptedContent = NULL;
if (pkcs7 == NULL || pkcs7->singleCert == NULL ||
pkcs7->singleCertSz == 0 || pkcs7->privateKey == NULL ||
pkcs7->privateKeySz == 0)
return BAD_FUNC_ARG;
if (pkiMsg == NULL || pkiMsgSz == 0 ||
output == NULL || outputSz == 0)
return BAD_FUNC_ARG;
/* read past ContentInfo, verify type is envelopedData */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (wc_GetContentType(pkiMsg, &idx, &contentType, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (contentType != ENVELOPED_DATA) {
WOLFSSL_MSG("PKCS#7 input not of type EnvelopedData");
return PKCS7_OID_E;
}
if (pkiMsg[idx++] != (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 0))
return ASN_PARSE_E;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* remove EnvelopedData and version */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (GetMyVersion(pkiMsg, &idx, &version, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* TODO :: make this more accurate */
if ((pkcs7->publicKeyOID == RSAk && version != 0) ||
(pkcs7->publicKeyOID == ECDSAk && version != 2)) {
WOLFSSL_MSG("PKCS#7 envelopedData needs to be of version 0");
return ASN_VERSION_E;
}
/* walk through RecipientInfo set, find correct recipient */
if (GetSet(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
#ifdef WOLFSSL_SMALL_STACK
decryptedKey = (byte*)XMALLOC(MAX_ENCRYPTED_KEY_SZ, NULL,
DYNAMIC_TYPE_PKCS7);
if (decryptedKey == NULL)
return MEMORY_E;
#endif
decryptedKeySz = MAX_ENCRYPTED_KEY_SZ;
ret = wc_PKCS7_DecodeRecipientInfos(pkcs7, pkiMsg, pkiMsgSz, &idx,
decryptedKey, &decryptedKeySz,
&recipFound);
if (ret != 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ret;
}
if (recipFound == 0) {
WOLFSSL_MSG("No recipient found in envelopedData that matches input");
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return PKCS7_RECIP_E;
}
/* remove EncryptedContentInfo */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ASN_PARSE_E;
}
if (wc_GetContentType(pkiMsg, &idx, &contentType, pkiMsgSz) < 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ASN_PARSE_E;
}
if (GetAlgoId(pkiMsg, &idx, &encOID, oidBlkType, pkiMsgSz) < 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ASN_PARSE_E;
}
blockKeySz = wc_PKCS7_GetOIDKeySize(encOID);
if (blockKeySz < 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return blockKeySz;
}
expBlockSz = wc_PKCS7_GetOIDBlockSize(encOID);
if (expBlockSz < 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return expBlockSz;
}
/* get block cipher IV, stored in OPTIONAL parameter of AlgoID */
if (pkiMsg[idx++] != ASN_OCTET_STRING) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ASN_PARSE_E;
}
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ASN_PARSE_E;
}
if (length != expBlockSz) {
WOLFSSL_MSG("Incorrect IV length, must be of content alg block size");
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ASN_PARSE_E;
}
XMEMCPY(tmpIv, &pkiMsg[idx], length);
idx += length;
/* read encryptedContent, cont[0] */
if (pkiMsg[idx++] != (ASN_CONTEXT_SPECIFIC | 0)) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ASN_PARSE_E;
}
if (GetLength(pkiMsg, &idx, &encryptedContentSz, pkiMsgSz) <= 0) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ASN_PARSE_E;
}
encryptedContent = (byte*)XMALLOC(encryptedContentSz, pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (encryptedContent == NULL) {
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return MEMORY_E;
}
XMEMCPY(encryptedContent, &pkiMsg[idx], encryptedContentSz);
/* decrypt encryptedContent */
ret = wc_PKCS7_DecryptContent(encOID, decryptedKey, blockKeySz,
tmpIv, expBlockSz, encryptedContent,
encryptedContentSz, encryptedContent);
if (ret != 0) {
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return ret;
}
padLen = encryptedContent[encryptedContentSz-1];
/* copy plaintext to output */
XMEMCPY(output, encryptedContent, encryptedContentSz - padLen);
/* free memory, zero out keys */
ForceZero(decryptedKey, MAX_ENCRYPTED_KEY_SZ);
ForceZero(encryptedContent, encryptedContentSz);
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
#ifdef WOLFSSL_SMALL_STACK
XFREE(decryptedKey, NULL, DYNAMIC_TYPE_PKCS7);
#endif
return encryptedContentSz - padLen;
}
/* build PKCS#7 encryptedData content type, return encrypted size */
int wc_PKCS7_EncodeEncryptedData(PKCS7* pkcs7, byte* output, word32 outputSz)
{
int ret, idx = 0;
int totalSz, padSz, encryptedOutSz;
int contentInfoSeqSz, outerContentTypeSz, outerContentSz;
byte contentInfoSeq[MAX_SEQ_SZ];
byte outerContentType[MAX_ALGO_SZ];
byte outerContent[MAX_SEQ_SZ];
int encDataSeqSz, verSz, blockSz;
byte encDataSeq[MAX_SEQ_SZ];
byte ver[MAX_VERSION_SZ];
byte* plain = NULL;
byte* encryptedContent = NULL;
int encContentOctetSz, encContentSeqSz, contentTypeSz;
int contentEncAlgoSz, ivOctetStringSz;
byte encContentSeq[MAX_SEQ_SZ];
byte contentType[MAX_ALGO_SZ];
byte contentEncAlgo[MAX_ALGO_SZ];
byte tmpIv[MAX_CONTENT_IV_SIZE];
byte ivOctetString[MAX_OCTET_STR_SZ];
byte encContentOctet[MAX_OCTET_STR_SZ];
byte attribSet[MAX_SET_SZ];
EncodedAttrib* attribs = NULL;
word32 attribsSz;
word32 attribsCount;
word32 attribsSetSz;
byte* flatAttribs = NULL;
if (pkcs7 == NULL || pkcs7->content == NULL || pkcs7->contentSz == 0 ||
pkcs7->encryptOID == 0 || pkcs7->encryptionKey == NULL ||
pkcs7->encryptionKeySz == 0)
return BAD_FUNC_ARG;
if (output == NULL || outputSz == 0)
return BAD_FUNC_ARG;
/* outer content type */
outerContentTypeSz = wc_SetContentType(ENCRYPTED_DATA, outerContentType);
/* version, 2 if unprotectedAttrs present, 0 if absent */
if (pkcs7->unprotectedAttribsSz > 0) {
verSz = SetMyVersion(2, ver, 0);
} else {
verSz = SetMyVersion(0, ver, 0);
}
/* EncryptedContentInfo */
contentTypeSz = wc_SetContentType(pkcs7->contentOID, contentType);
if (contentTypeSz == 0)
return BAD_FUNC_ARG;
/* allocate encrypted content buffer, do PKCS#7 padding */
blockSz = wc_PKCS7_GetOIDBlockSize(pkcs7->encryptOID);
if (blockSz < 0)
return blockSz;
padSz = wc_PKCS7_GetPadSize(pkcs7->contentSz, blockSz);
if (padSz < 0)
return padSz;
encryptedOutSz = pkcs7->contentSz + padSz;
plain = (byte*)XMALLOC(encryptedOutSz, pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (plain == NULL)
return MEMORY_E;
ret = wc_PKCS7_PadData(pkcs7->content, pkcs7->contentSz, plain,
encryptedOutSz, blockSz);
if (ret < 0) {
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return ret;
}
encryptedContent = (byte*)XMALLOC(encryptedOutSz, pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (encryptedContent == NULL) {
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return MEMORY_E;
}
/* put together IV OCTET STRING */
ivOctetStringSz = SetOctetString(blockSz, ivOctetString);
/* build up ContentEncryptionAlgorithmIdentifier sequence,
adding (ivOctetStringSz + blockSz) for IV OCTET STRING */
contentEncAlgoSz = SetAlgoID(pkcs7->encryptOID, contentEncAlgo,
oidBlkType, ivOctetStringSz + blockSz);
if (contentEncAlgoSz == 0) {
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return BAD_FUNC_ARG;
}
/* encrypt content */
ret = wc_PKCS7_GenerateIV(NULL, tmpIv, blockSz);
if (ret != 0)
return ret;
ret = wc_PKCS7_EncryptContent(pkcs7->encryptOID, pkcs7->encryptionKey,
pkcs7->encryptionKeySz, tmpIv, blockSz, plain, encryptedOutSz,
encryptedContent);
if (ret != 0) {
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return ret;
}
encContentOctetSz = SetImplicit(ASN_OCTET_STRING, 0,
encryptedOutSz, encContentOctet);
encContentSeqSz = SetSequence(contentTypeSz + contentEncAlgoSz +
ivOctetStringSz + blockSz +
encContentOctetSz + encryptedOutSz,
encContentSeq);
/* optional UnprotectedAttributes */
if (pkcs7->unprotectedAttribsSz != 0) {
if (pkcs7->unprotectedAttribs == NULL) {
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return BAD_FUNC_ARG;
}
attribs = (EncodedAttrib*)XMALLOC(
sizeof(EncodedAttrib) * pkcs7->unprotectedAttribsSz,
pkcs7->heap, DYNAMIC_TYPE_PKCS);
if (attribs == NULL) {
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return MEMORY_E;
}
attribsCount = pkcs7->unprotectedAttribsSz;
attribsSz = EncodeAttributes(attribs, pkcs7->unprotectedAttribsSz,
pkcs7->unprotectedAttribs,
pkcs7->unprotectedAttribsSz);
flatAttribs = (byte*)XMALLOC(attribsSz, pkcs7->heap, DYNAMIC_TYPE_PKCS);
if (flatAttribs == NULL) {
XFREE(attribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return MEMORY_E;
}
FlattenAttributes(flatAttribs, attribs, attribsCount);
attribsSetSz = SetImplicit(ASN_SET, 1, attribsSz, attribSet);
} else {
attribsSz = 0;
attribsSetSz = 0;
}
/* keep track of sizes for outer wrapper layering */
totalSz = verSz + encContentSeqSz + contentTypeSz + contentEncAlgoSz +
ivOctetStringSz + blockSz + encContentOctetSz + encryptedOutSz +
attribsSz + attribsSetSz;;
/* EncryptedData */
encDataSeqSz = SetSequence(totalSz, encDataSeq);
totalSz += encDataSeqSz;
/* outer content */
outerContentSz = SetExplicit(0, totalSz, outerContent);
totalSz += outerContentTypeSz;
totalSz += outerContentSz;
/* ContentInfo */
contentInfoSeqSz = SetSequence(totalSz, contentInfoSeq);
totalSz += contentInfoSeqSz;
if (totalSz > (int)outputSz) {
WOLFSSL_MSG("PKCS#7 output buffer too small");
if (pkcs7->unprotectedAttribsSz != 0) {
XFREE(attribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
XFREE(attribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
}
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return BUFFER_E;
}
XMEMCPY(output + idx, contentInfoSeq, contentInfoSeqSz);
idx += contentInfoSeqSz;
XMEMCPY(output + idx, outerContentType, outerContentTypeSz);
idx += outerContentTypeSz;
XMEMCPY(output + idx, outerContent, outerContentSz);
idx += outerContentSz;
XMEMCPY(output + idx, encDataSeq, encDataSeqSz);
idx += encDataSeqSz;
XMEMCPY(output + idx, ver, verSz);
idx += verSz;
XMEMCPY(output + idx, encContentSeq, encContentSeqSz);
idx += encContentSeqSz;
XMEMCPY(output + idx, contentType, contentTypeSz);
idx += contentTypeSz;
XMEMCPY(output + idx, contentEncAlgo, contentEncAlgoSz);
idx += contentEncAlgoSz;
XMEMCPY(output + idx, ivOctetString, ivOctetStringSz);
idx += ivOctetStringSz;
XMEMCPY(output + idx, tmpIv, blockSz);
idx += blockSz;
XMEMCPY(output + idx, encContentOctet, encContentOctetSz);
idx += encContentOctetSz;
XMEMCPY(output + idx, encryptedContent, encryptedOutSz);
idx += encryptedOutSz;
if (pkcs7->unprotectedAttribsSz != 0) {
XMEMCPY(output + idx, attribSet, attribsSetSz);
idx += attribsSetSz;
XMEMCPY(output + idx, flatAttribs, attribsSz);
idx += attribsSz;
XFREE(attribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
XFREE(flatAttribs, pkcs7->heap, DYNAMIC_TYPE_PKCS);
}
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
XFREE(plain, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return idx;
}
/* decode and store unprotected attributes in PKCS7->decodedAttrib. Return
* 0 on success, negative on error. User must call wc_PKCS7_Free(). */
static int wc_PKCS7_DecodeUnprotectedAttributes(PKCS7* pkcs7, byte* pkiMsg,
word32 pkiMsgSz, word32* inOutIdx)
{
int length, attribLen;
word32 oid, savedIdx, idx;
PKCS7DecodedAttrib* attrib = NULL;
if (pkcs7 == NULL || pkiMsg == NULL ||
pkiMsgSz == 0 || inOutIdx == NULL)
return BAD_FUNC_ARG;
idx = *inOutIdx;
if (pkiMsg[idx] != (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 1))
return ASN_PARSE_E;
idx++;
if (GetLength(pkiMsg, &idx, &attribLen, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* loop through attributes */
while (attribLen > 0) {
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
attribLen -= (length + 2); /* TAG + LENGTH + DATA */
savedIdx = idx;
attrib = (PKCS7DecodedAttrib*)XMALLOC(sizeof(PKCS7DecodedAttrib),
pkcs7->heap, DYNAMIC_TYPE_PKCS);
if (attrib == NULL) {
return MEMORY_E;
}
XMEMSET(attrib, 0, sizeof(PKCS7DecodedAttrib));
/* save attribute OID bytes and size */
if (GetObjectId(pkiMsg, &idx, &oid, oidIgnoreType, pkiMsgSz) < 0) {
XFREE(attrib, pkcs7->heap, DYNAMIC_TYPE_PKCS);
return ASN_PARSE_E;
}
attrib->oidSz = idx - savedIdx;
attrib->oid = (byte*)XMALLOC(attrib->oidSz, pkcs7->heap,
DYNAMIC_TYPE_PKCS);
if (attrib->oid == NULL) {
XFREE(attrib, pkcs7->heap, DYNAMIC_TYPE_PKCS);
return MEMORY_E;
}
XMEMCPY(attrib->oid, pkiMsg + savedIdx, attrib->oidSz);
/* save attribute value bytes and size */
if (GetSet(pkiMsg, &idx, &length, pkiMsgSz) < 0) {
XFREE(attrib->oid, pkcs7->heap, DYNAMIC_TYPE_PKCS);
XFREE(attrib, pkcs7->heap, DYNAMIC_TYPE_PKCS);
return ASN_PARSE_E;
}
if ((pkiMsgSz - idx) < (word32)length) {
XFREE(attrib->oid, pkcs7->heap, DYNAMIC_TYPE_PKCS);
XFREE(attrib, pkcs7->heap, DYNAMIC_TYPE_PKCS);
return ASN_PARSE_E;
}
attrib->valueSz = (word32)length;
attrib->value = (byte*)XMALLOC(attrib->valueSz, pkcs7->heap,
DYNAMIC_TYPE_PKCS);
if (attrib->value == NULL) {
XFREE(attrib->oid, pkcs7->heap, DYNAMIC_TYPE_PKCS);
XFREE(attrib, pkcs7->heap, DYNAMIC_TYPE_PKCS);
return MEMORY_E;
}
XMEMCPY(attrib->value, pkiMsg + idx, attrib->valueSz);
idx += length;
/* store attribute in linked list */
if (pkcs7->decodedAttrib != NULL) {
attrib->next = pkcs7->decodedAttrib;
pkcs7->decodedAttrib = attrib;
} else {
pkcs7->decodedAttrib = attrib;
}
}
*inOutIdx = idx;
return 0;
}
/* unwrap and decrypt PKCS#7/CMS encrypted-data object, returned decoded size */
int wc_PKCS7_DecodeEncryptedData(PKCS7* pkcs7, byte* pkiMsg, word32 pkiMsgSz,
byte* output, word32 outputSz)
{
int ret, version, length, haveAttribs;
word32 idx = 0;
word32 contentType, encOID;
int expBlockSz;
byte tmpIv[MAX_CONTENT_IV_SIZE];
int encryptedContentSz;
byte padLen;
byte* encryptedContent = NULL;
if (pkcs7 == NULL || pkcs7->encryptionKey == NULL ||
pkcs7->encryptionKeySz == 0)
return BAD_FUNC_ARG;
if (pkiMsg == NULL || pkiMsgSz == 0 ||
output == NULL || outputSz == 0)
return BAD_FUNC_ARG;
/* read past ContentInfo, verify type is encrypted-data */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (wc_GetContentType(pkiMsg, &idx, &contentType, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (contentType != ENCRYPTED_DATA) {
WOLFSSL_MSG("PKCS#7 input not of type EncryptedData");
return PKCS7_OID_E;
}
if (pkiMsg[idx++] != (ASN_CONSTRUCTED | ASN_CONTEXT_SPECIFIC | 0))
return ASN_PARSE_E;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* remove EncryptedData and version */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* get version, check later */
haveAttribs = 0;
if (GetMyVersion(pkiMsg, &idx, &version, pkiMsgSz) < 0)
return ASN_PARSE_E;
/* remove EncryptedContentInfo */
if (GetSequence(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (wc_GetContentType(pkiMsg, &idx, &contentType, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (GetAlgoId(pkiMsg, &idx, &encOID, oidBlkType, pkiMsgSz) < 0)
return ASN_PARSE_E;
expBlockSz = wc_PKCS7_GetOIDBlockSize(encOID);
if (expBlockSz < 0)
return expBlockSz;
/* get block cipher IV, stored in OPTIONAL parameter of AlgoID */
if (pkiMsg[idx++] != ASN_OCTET_STRING)
return ASN_PARSE_E;
if (GetLength(pkiMsg, &idx, &length, pkiMsgSz) < 0)
return ASN_PARSE_E;
if (length != expBlockSz) {
WOLFSSL_MSG("Incorrect IV length, must be of content alg block size");
return ASN_PARSE_E;
}
XMEMCPY(tmpIv, &pkiMsg[idx], length);
idx += length;
/* read encryptedContent, cont[0] */
if (pkiMsg[idx++] != (ASN_CONTEXT_SPECIFIC | 0))
return ASN_PARSE_E;
if (GetLength(pkiMsg, &idx, &encryptedContentSz, pkiMsgSz) <= 0)
return ASN_PARSE_E;
encryptedContent = (byte*)XMALLOC(encryptedContentSz, pkcs7->heap,
DYNAMIC_TYPE_PKCS7);
if (encryptedContent == NULL)
return MEMORY_E;
XMEMCPY(encryptedContent, &pkiMsg[idx], encryptedContentSz);
idx += encryptedContentSz;
/* decrypt encryptedContent */
ret = wc_PKCS7_DecryptContent(encOID, pkcs7->encryptionKey,
pkcs7->encryptionKeySz, tmpIv, expBlockSz,
encryptedContent, encryptedContentSz,
encryptedContent);
if (ret != 0) {
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return ret;
}
padLen = encryptedContent[encryptedContentSz-1];
/* copy plaintext to output */
XMEMCPY(output, encryptedContent, encryptedContentSz - padLen);
/* get implicit[1] unprotected attributes, optional */
pkcs7->decodedAttrib = NULL;
if (idx < pkiMsgSz) {
haveAttribs = 1;
ret = wc_PKCS7_DecodeUnprotectedAttributes(pkcs7, pkiMsg,
pkiMsgSz, &idx);
if (ret != 0) {
ForceZero(encryptedContent, encryptedContentSz);
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return ASN_PARSE_E;
}
}
/* go back and check the version now that attribs have been processed */
if ((haveAttribs == 0 && version != 0) ||
(haveAttribs == 1 && version != 2) ) {
WOLFSSL_MSG("Wrong PKCS#7 EncryptedData version");
return ASN_VERSION_E;
}
ForceZero(encryptedContent, encryptedContentSz);
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
return encryptedContentSz - padLen;
}
#else /* HAVE_PKCS7 */
#ifdef _MSC_VER
/* 4206 warning for blank file */
#pragma warning(disable: 4206)
#endif
#endif /* HAVE_PKCS7 */