RetroZilla/security/nss/lib/pkcs12/p12dec.c
2018-05-19 22:01:21 +08:00

665 lines
16 KiB
C

/* 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/. */
#include "pkcs12.h"
#include "plarena.h"
#include "secpkcs7.h"
#include "p12local.h"
#include "secoid.h"
#include "secitem.h"
#include "secport.h"
#include "secasn1.h"
#include "secder.h"
#include "secerr.h"
#include "cert.h"
#include "certdb.h"
#include "p12plcy.h"
#include "p12.h"
#include "secpkcs5.h"
/* PFX extraction and validation routines */
/* decode the DER encoded PFX item. if unable to decode, check to see if it
* is an older PFX item. If that fails, assume the file was not a valid
* pfx file.
* the returned pfx structure should be destroyed using SEC_PKCS12DestroyPFX
*/
static SEC_PKCS12PFXItem *
sec_pkcs12_decode_pfx(SECItem *der_pfx)
{
SEC_PKCS12PFXItem *pfx;
SECStatus rv;
if(der_pfx == NULL) {
return NULL;
}
/* allocate the space for a new PFX item */
pfx = sec_pkcs12_new_pfx();
if(pfx == NULL) {
return NULL;
}
rv = SEC_ASN1DecodeItem(pfx->poolp, pfx, SEC_PKCS12PFXItemTemplate,
der_pfx);
/* if a failure occurred, check for older version...
* we also get rid of the old pfx structure, because we don't
* know where it failed and what data in may contain
*/
if(rv != SECSuccess) {
SEC_PKCS12DestroyPFX(pfx);
pfx = sec_pkcs12_new_pfx();
if(pfx == NULL) {
return NULL;
}
rv = SEC_ASN1DecodeItem(pfx->poolp, pfx, SEC_PKCS12PFXItemTemplate_OLD,
der_pfx);
if(rv != SECSuccess) {
PORT_SetError(SEC_ERROR_PKCS12_DECODING_PFX);
PORT_FreeArena(pfx->poolp, PR_TRUE);
return NULL;
}
pfx->old = PR_TRUE;
SGN_CopyDigestInfo(pfx->poolp, &pfx->macData.safeMac, &pfx->old_safeMac);
SECITEM_CopyItem(pfx->poolp, &pfx->macData.macSalt, &pfx->old_macSalt);
} else {
pfx->old = PR_FALSE;
}
/* convert bit string from bits to bytes */
pfx->macData.macSalt.len /= 8;
return pfx;
}
/* validate the integrity MAC used in the PFX. The MAC is generated
* per the PKCS 12 document. If the MAC is incorrect, it is most likely
* due to an invalid password.
* pwitem is the integrity password
* pfx is the decoded pfx item
*/
static PRBool
sec_pkcs12_check_pfx_mac(SEC_PKCS12PFXItem *pfx,
SECItem *pwitem)
{
SECItem *key = NULL, *mac = NULL, *data = NULL;
SECItem *vpwd = NULL;
SECOidTag algorithm;
PRBool ret = PR_FALSE;
if(pfx == NULL) {
return PR_FALSE;
}
algorithm = SECOID_GetAlgorithmTag(&pfx->macData.safeMac.digestAlgorithm);
switch(algorithm) {
/* only SHA1 hashing supported as a MACing algorithm */
case SEC_OID_SHA1:
if(pfx->old == PR_FALSE) {
pfx->swapUnicode = PR_FALSE;
}
recheckUnicodePassword:
vpwd = sec_pkcs12_create_virtual_password(pwitem,
&pfx->macData.macSalt,
pfx->swapUnicode);
if(vpwd == NULL) {
return PR_FALSE;
}
key = sec_pkcs12_generate_key_from_password(algorithm,
&pfx->macData.macSalt,
(pfx->old ? pwitem : vpwd));
/* free vpwd only for newer PFX */
if(vpwd) {
SECITEM_ZfreeItem(vpwd, PR_TRUE);
}
if(key == NULL) {
return PR_FALSE;
}
data = SEC_PKCS7GetContent(&pfx->authSafe);
if(data == NULL) {
break;
}
/* check MAC */
mac = sec_pkcs12_generate_mac(key, data, pfx->old);
ret = PR_TRUE;
if(mac) {
SECItem *safeMac = &pfx->macData.safeMac.digest;
if(SECITEM_CompareItem(mac, safeMac) != SECEqual) {
/* if we encounter an invalid mac, lets invert the
* password in case of unicode changes
*/
if(((!pfx->old) && pfx->swapUnicode) || (pfx->old)){
PORT_SetError(SEC_ERROR_PKCS12_INVALID_MAC);
ret = PR_FALSE;
} else {
SECITEM_ZfreeItem(mac, PR_TRUE);
pfx->swapUnicode = PR_TRUE;
goto recheckUnicodePassword;
}
}
SECITEM_ZfreeItem(mac, PR_TRUE);
} else {
ret = PR_FALSE;
}
break;
default:
PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_MAC_ALGORITHM);
ret = PR_FALSE;
break;
}
/* let success fall through */
if(key != NULL)
SECITEM_ZfreeItem(key, PR_TRUE);
return ret;
}
/* check the validity of the pfx structure. we currently only support
* password integrity mode, so we check the MAC.
*/
static PRBool
sec_pkcs12_validate_pfx(SEC_PKCS12PFXItem *pfx,
SECItem *pwitem)
{
SECOidTag contentType;
contentType = SEC_PKCS7ContentType(&pfx->authSafe);
switch(contentType)
{
case SEC_OID_PKCS7_DATA:
return sec_pkcs12_check_pfx_mac(pfx, pwitem);
break;
case SEC_OID_PKCS7_SIGNED_DATA:
default:
PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_TRANSPORT_MODE);
break;
}
return PR_FALSE;
}
/* decode and return the valid PFX. if the PFX item is not valid,
* NULL is returned.
*/
static SEC_PKCS12PFXItem *
sec_pkcs12_get_pfx(SECItem *pfx_data,
SECItem *pwitem)
{
SEC_PKCS12PFXItem *pfx;
PRBool valid_pfx;
if((pfx_data == NULL) || (pwitem == NULL)) {
return NULL;
}
pfx = sec_pkcs12_decode_pfx(pfx_data);
if(pfx == NULL) {
return NULL;
}
valid_pfx = sec_pkcs12_validate_pfx(pfx, pwitem);
if(valid_pfx != PR_TRUE) {
SEC_PKCS12DestroyPFX(pfx);
pfx = NULL;
}
return pfx;
}
/* authenticated safe decoding, validation, and access routines
*/
/* convert dogbert beta 3 authenticated safe structure to a post
* beta three structure, so that we don't have to change more routines.
*/
static SECStatus
sec_pkcs12_convert_old_auth_safe(SEC_PKCS12AuthenticatedSafe *asafe)
{
SEC_PKCS12Baggage *baggage;
SEC_PKCS12BaggageItem *bag;
SECStatus rv = SECSuccess;
if(asafe->old_baggage.espvks == NULL) {
/* XXX should the ASN1 engine produce a single NULL element list
* rather than setting the pointer to NULL?
* There is no need to return an error -- assume that the list
* was empty.
*/
return SECSuccess;
}
baggage = sec_pkcs12_create_baggage(asafe->poolp);
if(!baggage) {
return SECFailure;
}
bag = sec_pkcs12_create_external_bag(baggage);
if(!bag) {
return SECFailure;
}
PORT_Memcpy(&asafe->baggage, baggage, sizeof(SEC_PKCS12Baggage));
/* if there are shrouded keys, append them to the bag */
rv = SECSuccess;
if(asafe->old_baggage.espvks[0] != NULL) {
int nEspvk = 0;
rv = SECSuccess;
while((asafe->old_baggage.espvks[nEspvk] != NULL) &&
(rv == SECSuccess)) {
rv = sec_pkcs12_append_shrouded_key(bag,
asafe->old_baggage.espvks[nEspvk]);
nEspvk++;
}
}
return rv;
}
/* decodes the authenticated safe item. a return of NULL indicates
* an error. however, the error will have occurred either in memory
* allocation or in decoding the authenticated safe.
*
* if an old PFX item has been found, we want to convert the
* old authenticated safe to the new one.
*/
static SEC_PKCS12AuthenticatedSafe *
sec_pkcs12_decode_authenticated_safe(SEC_PKCS12PFXItem *pfx)
{
SECItem *der_asafe = NULL;
SEC_PKCS12AuthenticatedSafe *asafe = NULL;
SECStatus rv;
if(pfx == NULL) {
return NULL;
}
der_asafe = SEC_PKCS7GetContent(&pfx->authSafe);
if(der_asafe == NULL) {
/* XXX set error ? */
goto loser;
}
asafe = sec_pkcs12_new_asafe(pfx->poolp);
if(asafe == NULL) {
goto loser;
}
if(pfx->old == PR_FALSE) {
rv = SEC_ASN1DecodeItem(pfx->poolp, asafe,
SEC_PKCS12AuthenticatedSafeTemplate,
der_asafe);
asafe->old = PR_FALSE;
asafe->swapUnicode = pfx->swapUnicode;
} else {
/* handle beta exported files */
rv = SEC_ASN1DecodeItem(pfx->poolp, asafe,
SEC_PKCS12AuthenticatedSafeTemplate_OLD,
der_asafe);
asafe->safe = &(asafe->old_safe);
rv = sec_pkcs12_convert_old_auth_safe(asafe);
asafe->old = PR_TRUE;
}
if(rv != SECSuccess) {
goto loser;
}
asafe->poolp = pfx->poolp;
return asafe;
loser:
return NULL;
}
/* validates the safe within the authenticated safe item.
* in order to be valid:
* 1. the privacy salt must be present
* 2. the encryption algorithm must be supported (including
* export policy)
* PR_FALSE indicates an error, PR_TRUE indicates a valid safe
*/
static PRBool
sec_pkcs12_validate_encrypted_safe(SEC_PKCS12AuthenticatedSafe *asafe)
{
PRBool valid = PR_FALSE;
SECAlgorithmID *algid;
if(asafe == NULL) {
return PR_FALSE;
}
/* if mode is password privacy, then privacySalt is assumed
* to be non-zero.
*/
if(asafe->privacySalt.len != 0) {
valid = PR_TRUE;
asafe->privacySalt.len /= 8;
} else {
PORT_SetError(SEC_ERROR_PKCS12_CORRUPT_PFX_STRUCTURE);
return PR_FALSE;
}
/* until spec changes, content will have between 2 and 8 bytes depending
* upon the algorithm used if certs are unencrypted...
* also want to support case where content is empty -- which we produce
*/
if(SEC_PKCS7IsContentEmpty(asafe->safe, 8) == PR_TRUE) {
asafe->emptySafe = PR_TRUE;
return PR_TRUE;
}
asafe->emptySafe = PR_FALSE;
/* make sure that a pbe algorithm is being used */
algid = SEC_PKCS7GetEncryptionAlgorithm(asafe->safe);
if(algid != NULL) {
if(SEC_PKCS5IsAlgorithmPBEAlg(algid)) {
valid = SEC_PKCS12DecryptionAllowed(algid);
if(valid == PR_FALSE) {
PORT_SetError(SEC_ERROR_BAD_EXPORT_ALGORITHM);
}
} else {
PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_PBE_ALGORITHM);
valid = PR_FALSE;
}
} else {
valid = PR_FALSE;
PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_PBE_ALGORITHM);
}
return valid;
}
/* validates authenticates safe:
* 1. checks that the version is supported
* 2. checks that only password privacy mode is used (currently)
* 3. further, makes sure safe has appropriate policies per above function
* PR_FALSE indicates failure.
*/
static PRBool
sec_pkcs12_validate_auth_safe(SEC_PKCS12AuthenticatedSafe *asafe)
{
PRBool valid = PR_TRUE;
SECOidTag safe_type;
int version;
if(asafe == NULL) {
return PR_FALSE;
}
/* check version, since it is default it may not be present.
* therefore, assume ok
*/
if((asafe->version.len > 0) && (asafe->old == PR_FALSE)) {
version = DER_GetInteger(&asafe->version);
if(version > SEC_PKCS12_PFX_VERSION) {
PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_VERSION);
return PR_FALSE;
}
}
/* validate password mode is being used */
safe_type = SEC_PKCS7ContentType(asafe->safe);
switch(safe_type)
{
case SEC_OID_PKCS7_ENCRYPTED_DATA:
valid = sec_pkcs12_validate_encrypted_safe(asafe);
break;
case SEC_OID_PKCS7_ENVELOPED_DATA:
default:
PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_TRANSPORT_MODE);
valid = PR_FALSE;
break;
}
return valid;
}
/* retrieves the authenticated safe item from the PFX item
* before returning the authenticated safe, the validity of the
* authenticated safe is checked and if valid, returned.
* a return of NULL indicates that an error occurred.
*/
static SEC_PKCS12AuthenticatedSafe *
sec_pkcs12_get_auth_safe(SEC_PKCS12PFXItem *pfx)
{
SEC_PKCS12AuthenticatedSafe *asafe;
PRBool valid_safe;
if(pfx == NULL) {
return NULL;
}
asafe = sec_pkcs12_decode_authenticated_safe(pfx);
if(asafe == NULL) {
return NULL;
}
valid_safe = sec_pkcs12_validate_auth_safe(asafe);
if(valid_safe != PR_TRUE) {
asafe = NULL;
} else if(asafe) {
asafe->baggage.poolp = asafe->poolp;
}
return asafe;
}
/* decrypts the authenticated safe.
* a return of anything but SECSuccess indicates an error. the
* password is not known to be valid until the call to the
* function sec_pkcs12_get_safe_contents. If decoding the safe
* fails, it is assumed the password was incorrect and the error
* is set then. any failure here is assumed to be due to
* internal problems in SEC_PKCS7DecryptContents or below.
*/
static SECStatus
sec_pkcs12_decrypt_auth_safe(SEC_PKCS12AuthenticatedSafe *asafe,
SECItem *pwitem,
void *wincx)
{
SECStatus rv = SECFailure;
SECItem *vpwd = NULL;
if((asafe == NULL) || (pwitem == NULL)) {
return SECFailure;
}
if(asafe->old == PR_FALSE) {
vpwd = sec_pkcs12_create_virtual_password(pwitem, &asafe->privacySalt,
asafe->swapUnicode);
if(vpwd == NULL) {
return SECFailure;
}
}
rv = SEC_PKCS7DecryptContents(asafe->poolp, asafe->safe,
(asafe->old ? pwitem : vpwd), wincx);
if(asafe->old == PR_FALSE) {
SECITEM_ZfreeItem(vpwd, PR_TRUE);
}
return rv;
}
/* extract the safe from the authenticated safe.
* if we are unable to decode the safe, then it is likely that the
* safe has not been decrypted or the password used to decrypt
* the safe was invalid. we assume that the password was invalid and
* set an error accordingly.
* a return of NULL indicates that an error occurred.
*/
static SEC_PKCS12SafeContents *
sec_pkcs12_get_safe_contents(SEC_PKCS12AuthenticatedSafe *asafe)
{
SECItem *src = NULL;
SEC_PKCS12SafeContents *safe = NULL;
SECStatus rv = SECFailure;
if(asafe == NULL) {
return NULL;
}
safe = (SEC_PKCS12SafeContents *)PORT_ArenaZAlloc(asafe->poolp,
sizeof(SEC_PKCS12SafeContents));
if(safe == NULL) {
return NULL;
}
safe->poolp = asafe->poolp;
safe->old = asafe->old;
safe->swapUnicode = asafe->swapUnicode;
src = SEC_PKCS7GetContent(asafe->safe);
if(src != NULL) {
const SEC_ASN1Template *theTemplate;
if(asafe->old != PR_TRUE) {
theTemplate = SEC_PKCS12SafeContentsTemplate;
} else {
theTemplate = SEC_PKCS12SafeContentsTemplate_OLD;
}
rv = SEC_ASN1DecodeItem(asafe->poolp, safe, theTemplate, src);
/* if we could not decode the item, password was probably invalid */
if(rv != SECSuccess) {
safe = NULL;
PORT_SetError(SEC_ERROR_PKCS12_PRIVACY_PASSWORD_INCORRECT);
}
} else {
PORT_SetError(SEC_ERROR_PKCS12_CORRUPT_PFX_STRUCTURE);
rv = SECFailure;
}
return safe;
}
/* import PFX item
* der_pfx is the der encoded pfx structure
* pbef and pbearg are the integrity/encryption password call back
* ncCall is the nickname collision calllback
* slot is the destination token
* wincx window handler
*
* on error, error code set and SECFailure returned
*/
SECStatus
SEC_PKCS12PutPFX(SECItem *der_pfx, SECItem *pwitem,
SEC_PKCS12NicknameCollisionCallback ncCall,
PK11SlotInfo *slot,
void *wincx)
{
SEC_PKCS12PFXItem *pfx;
SEC_PKCS12AuthenticatedSafe *asafe;
SEC_PKCS12SafeContents *safe_contents = NULL;
SECStatus rv;
if(!der_pfx || !pwitem || !slot) {
return SECFailure;
}
/* decode and validate each section */
rv = SECFailure;
pfx = sec_pkcs12_get_pfx(der_pfx, pwitem);
if(pfx != NULL) {
asafe = sec_pkcs12_get_auth_safe(pfx);
if(asafe != NULL) {
/* decrypt safe -- only if not empty */
if(asafe->emptySafe != PR_TRUE) {
rv = sec_pkcs12_decrypt_auth_safe(asafe, pwitem, wincx);
if(rv == SECSuccess) {
safe_contents = sec_pkcs12_get_safe_contents(asafe);
if(safe_contents == NULL) {
rv = SECFailure;
}
}
} else {
safe_contents = sec_pkcs12_create_safe_contents(asafe->poolp);
if(safe_contents == NULL) {
rv = SECFailure;
} else {
safe_contents->swapUnicode = pfx->swapUnicode;
rv = SECSuccess;
}
}
/* get safe contents and begin import */
if(rv == SECSuccess) {
SEC_PKCS12DecoderContext *p12dcx;
p12dcx = sec_PKCS12ConvertOldSafeToNew(pfx->poolp, slot,
pfx->swapUnicode,
pwitem, wincx, safe_contents,
&asafe->baggage);
if(!p12dcx) {
rv = SECFailure;
goto loser;
}
if(SEC_PKCS12DecoderValidateBags(p12dcx, ncCall)
!= SECSuccess) {
rv = SECFailure;
goto loser;
}
rv = SEC_PKCS12DecoderImportBags(p12dcx);
}
}
}
loser:
if(pfx) {
SEC_PKCS12DestroyPFX(pfx);
}
return rv;
}
PRBool
SEC_PKCS12ValidData(char *buf, int bufLen, long int totalLength)
{
int lengthLength;
PRBool valid = PR_FALSE;
if(buf == NULL) {
return PR_FALSE;
}
/* check for constructed sequence identifier tag */
if(*buf == (SEC_ASN1_CONSTRUCTED | SEC_ASN1_SEQUENCE)) {
totalLength--; /* header byte taken care of */
buf++;
lengthLength = (long int)SEC_ASN1LengthLength(totalLength - 1);
if(totalLength > 0x7f) {
lengthLength--;
*buf &= 0x7f; /* remove bit 8 indicator */
if((*buf - (char)lengthLength) == 0) {
valid = PR_TRUE;
}
} else {
lengthLength--;
if((*buf - (char)lengthLength) == 0) {
valid = PR_TRUE;
}
}
}
return valid;
}