/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*

 * Code for dealing with X509.V3 extensions.

 */

#include "cert.h"

#include "secitem.h"

#include "secoid.h"

#include "secder.h"

#include "secasn1.h"

#include "certxutl.h"

#include "secerr.h"

SECStatus

CERT_FindCertExtensionByOID(CERTCertificate *cert, SECItem *oid, SECItem *value)

{

    return (cert_FindExtensionByOID(cert->extensions, oid, value));

}

SECStatus

CERT_FindCertExtension(const CERTCertificate *cert, int tag, SECItem *value)

{

    return (cert_FindExtension(cert->extensions, tag, value));

}

static void

SetExts(void *object, CERTCertExtension **exts)

{

    CERTCertificate *cert = (CERTCertificate *)object;

    cert->extensions = exts;

    DER_SetUInteger(cert->arena, &(cert->version), SEC_CERTIFICATE_VERSION_3);

}

void *

CERT_StartCertExtensions(CERTCertificate *cert)

{

    return (cert_StartExtensions((void *)cert, cert->arena, SetExts));

}

/*

 * get the value of the Netscape Certificate Type Extension

 */

SECStatus

CERT_FindNSCertTypeExtension(CERTCertificate *cert, SECItem *retItem)

{

    return (CERT_FindBitStringExtension(

        cert->extensions, SEC_OID_NS_CERT_EXT_CERT_TYPE, retItem));

}

/*

 * get the value of a string type extension

 */

char *

CERT_FindNSStringExtension(CERTCertificate *cert, int oidtag)

{

    SECItem wrapperItem, tmpItem = { siBuffer, 0 };

    SECStatus rv;

    PLArenaPool *arena = NULL;

    char *retstring = NULL;

    wrapperItem.data = NULL;

    tmpItem.data = NULL;

    arena = PORT_NewArena(DER_DEFAULT_CHUNKSIZE);

    if (!arena) {

        goto loser;

    }

    rv = cert_FindExtension(cert->extensions, oidtag, &wrapperItem);

    if (rv != SECSuccess) {

        goto loser;

    }

    rv = SEC_QuickDERDecodeItem(

        arena, &tmpItem, SEC_ASN1_GET(SEC_IA5StringTemplate), &wrapperItem);

    if (rv != SECSuccess) {

        goto loser;

    }

    retstring = (char *)PORT_Alloc(tmpItem.len + 1);

    if (retstring == NULL) {

        goto loser;

    }

    PORT_Memcpy(retstring, tmpItem.data, tmpItem.len);

    retstring[tmpItem.len] = '\0';

loser:

    if (arena) {

        PORT_FreeArena(arena, PR_FALSE);

    }

    if (wrapperItem.data) {

        PORT_Free(wrapperItem.data);

    }

    return (retstring);

}

/*

 * get the value of the X.509 v3 Key Usage Extension

 */

SECStatus

CERT_FindKeyUsageExtension(CERTCertificate *cert, SECItem *retItem)

{

    return (CERT_FindBitStringExtension(cert->extensions,

                                        SEC_OID_X509_KEY_USAGE, retItem));

}

/*

 * get the value of the X.509 v3 Key Usage Extension

 */

SECStatus

CERT_FindSubjectKeyIDExtension(CERTCertificate *cert, SECItem *retItem)

{

    SECStatus rv;

    SECItem encodedValue = { siBuffer, NULL, 0 };

    SECItem decodedValue = { siBuffer, NULL, 0 };

    rv = cert_FindExtension(cert->extensions, SEC_OID_X509_SUBJECT_KEY_ID,

                            &encodedValue);

    if (rv == SECSuccess) {

        PORTCheapArenaPool tmpArena;

        PORT_InitCheapArena(&tmpArena, DER_DEFAULT_CHUNKSIZE);

        rv = SEC_QuickDERDecodeItem(&tmpArena.arena, &decodedValue,

                                    SEC_ASN1_GET(SEC_OctetStringTemplate),

                                    &encodedValue);

        if (rv == SECSuccess) {

            rv = SECITEM_CopyItem(NULL, retItem, &decodedValue);

        }

        PORT_DestroyCheapArena(&tmpArena);

    }

    SECITEM_FreeItem(&encodedValue, PR_FALSE);

    return rv;

}

SECStatus

CERT_FindBasicConstraintExten(CERTCertificate *cert,

                              CERTBasicConstraints *value)

{

    SECItem encodedExtenValue;

    SECStatus rv;

    encodedExtenValue.data = NULL;

    encodedExtenValue.len = 0;

    rv = cert_FindExtension(cert->extensions, SEC_OID_X509_BASIC_CONSTRAINTS,

                            &encodedExtenValue);

    if (rv != SECSuccess) {

        return (rv);

    }

    rv = CERT_DecodeBasicConstraintValue(value, &encodedExtenValue);

    /* free the raw extension data */

    PORT_Free(encodedExtenValue.data);

    encodedExtenValue.data = NULL;

    return (rv);

}

CERTAuthKeyID *

CERT_FindAuthKeyIDExten(PLArenaPool *arena, CERTCertificate *cert)

{

    SECItem encodedExtenValue;

    SECStatus rv;

    CERTAuthKeyID *ret;

    encodedExtenValue.data = NULL;

    encodedExtenValue.len = 0;

    rv = cert_FindExtension(cert->extensions, SEC_OID_X509_AUTH_KEY_ID,

                            &encodedExtenValue);

    if (rv != SECSuccess) {

        return (NULL);

    }

    ret = CERT_DecodeAuthKeyID(arena, &encodedExtenValue);

    PORT_Free(encodedExtenValue.data);

    encodedExtenValue.data = NULL;

    return (ret);

}

SECStatus

CERT_CheckCertUsage(CERTCertificate *cert, unsigned char usage)

{

    SECItem keyUsage;

    SECStatus rv;

    /* There is no extension, v1 or v2 certificate */

    if (cert->extensions == NULL) {

        return (SECSuccess);

    }

    keyUsage.data = NULL;

    /* This code formerly ignored the Key Usage extension if it was

    ** marked non-critical.  That was wrong.  Since we do understand it,

    ** we are obligated to honor it, whether or not it is critical.

    */

    rv = CERT_FindKeyUsageExtension(cert, &keyUsage);

    if (rv == SECFailure) {

        rv = (PORT_GetError() == SEC_ERROR_EXTENSION_NOT_FOUND) ? SECSuccess

                                                                : SECFailure;

    } else if (!keyUsage.data || !keyUsage.len || !(keyUsage.data[0] & usage)) {

        PORT_SetError(SEC_ERROR_CERT_USAGES_INVALID);

        rv = SECFailure;

    }

    PORT_Free(keyUsage.data);

    return (rv);

}