crmf_lib.c
/*-
* Copyright 2007-2020 The OpenSSL Project Authors. All Rights Reserved.
* Copyright Nokia 2007-2018
* Copyright Siemens AG 2015-2019
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*
* CRMF implementation by Martin Peylo, Miikka Viljanen, and David von Oheimb.
*/
/*
* This file contains the functions that handle the individual items inside
* the CRMF structures
*/
/*
* NAMING
*
* The 0 functions use the supplied structure pointer directly in the parent and
* it will be freed up when the parent is freed.
*
* The 1 functions use a copy of the supplied structure pointer (or in some
* cases increases its link count) in the parent and so both should be freed up.
*/
#include <openssl/asn1t.h>
#include "crmf_local.h"
#include "internal/constant_time.h"
/* explicit #includes not strictly needed since implied by the above: */
#include <openssl/crmf.h>
#include <openssl/err.h>
#include <openssl/evp.h>
/*-
* atyp = Attribute Type
* valt = Value Type
* ctrlinf = "regCtrl" or "regInfo"
*/
#define IMPLEMENT_CRMF_CTRL_FUNC(atyp, valt, ctrlinf) \
int OSSL_CRMF_MSG_set1_##ctrlinf##_##atyp(OSSL_CRMF_MSG *msg, \
const valt *in) \
{ \
OSSL_CRMF_ATTRIBUTETYPEANDVALUE *atav = NULL; \
\
if (msg == NULL || in == NULL) \
goto err; \
if ((atav = OSSL_CRMF_ATTRIBUTETYPEANDVALUE_new()) == NULL) \
goto err; \
if ((atav->type = OBJ_nid2obj(NID_id_##ctrlinf##_##atyp)) == NULL) \
goto err; \
if ((atav->value.atyp = valt##_dup(in)) == NULL) \
goto err; \
if (!OSSL_CRMF_MSG_push0_##ctrlinf(msg, atav)) \
goto err; \
return 1; \
err: \
OSSL_CRMF_ATTRIBUTETYPEANDVALUE_free(atav); \
return 0; \
}
/*-
* Pushes the given control attribute into the controls stack of a CertRequest
* (section 6)
* returns 1 on success, 0 on error
*/
static int OSSL_CRMF_MSG_push0_regCtrl(OSSL_CRMF_MSG *crm,
OSSL_CRMF_ATTRIBUTETYPEANDVALUE *ctrl)
{
int new = 0;
if (crm == NULL || crm->certReq == NULL || ctrl == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_MSG_PUSH0_REGCTRL, CRMF_R_NULL_ARGUMENT);
return 0;
}
if (crm->certReq->controls == NULL) {
crm->certReq->controls = sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_new_null();
if (crm->certReq->controls == NULL)
goto err;
new = 1;
}
if (!sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_push(crm->certReq->controls, ctrl))
goto err;
return 1;
err:
if (new != 0) {
sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_free(crm->certReq->controls);
crm->certReq->controls = NULL;
}
return 0;
}
/* id-regCtrl-regToken Control (section 6.1) */
IMPLEMENT_CRMF_CTRL_FUNC(regToken, ASN1_STRING, regCtrl)
/* id-regCtrl-authenticator Control (section 6.2) */
#define ASN1_UTF8STRING_dup ASN1_STRING_dup
IMPLEMENT_CRMF_CTRL_FUNC(authenticator, ASN1_UTF8STRING, regCtrl)
int OSSL_CRMF_MSG_set0_SinglePubInfo(OSSL_CRMF_SINGLEPUBINFO *spi,
int method, GENERAL_NAME *nm)
{
if (spi == NULL
|| method < OSSL_CRMF_PUB_METHOD_DONTCARE
|| method > OSSL_CRMF_PUB_METHOD_LDAP) {
CRMFerr(CRMF_F_OSSL_CRMF_MSG_SET0_SINGLEPUBINFO,
ERR_R_PASSED_INVALID_ARGUMENT);
return 0;
}
if (!ASN1_INTEGER_set(spi->pubMethod, method))
return 0;
GENERAL_NAME_free(spi->pubLocation);
spi->pubLocation = nm;
return 1;
}
int
OSSL_CRMF_MSG_PKIPublicationInfo_push0_SinglePubInfo(OSSL_CRMF_PKIPUBLICATIONINFO *pi,
OSSL_CRMF_SINGLEPUBINFO *spi)
{
if (pi == NULL || spi == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_MSG_PKIPUBLICATIONINFO_PUSH0_SINGLEPUBINFO,
CRMF_R_NULL_ARGUMENT);
return 0;
}
if (pi->pubInfos == NULL)
pi->pubInfos = sk_OSSL_CRMF_SINGLEPUBINFO_new_null();
if (pi->pubInfos == NULL)
return 0;
return sk_OSSL_CRMF_SINGLEPUBINFO_push(pi->pubInfos, spi);
}
int OSSL_CRMF_MSG_set_PKIPublicationInfo_action(OSSL_CRMF_PKIPUBLICATIONINFO *pi,
int action)
{
if (pi == NULL
|| action < OSSL_CRMF_PUB_ACTION_DONTPUBLISH
|| action > OSSL_CRMF_PUB_ACTION_PLEASEPUBLISH) {
CRMFerr(CRMF_F_OSSL_CRMF_MSG_SET_PKIPUBLICATIONINFO_ACTION,
ERR_R_PASSED_INVALID_ARGUMENT);
return 0;
}
return ASN1_INTEGER_set(pi->action, action);
}
/* id-regCtrl-pkiPublicationInfo Control (section 6.3) */
IMPLEMENT_CRMF_CTRL_FUNC(pkiPublicationInfo, OSSL_CRMF_PKIPUBLICATIONINFO,
regCtrl)
/* id-regCtrl-oldCertID Control (section 6.5) from the given */
IMPLEMENT_CRMF_CTRL_FUNC(oldCertID, OSSL_CRMF_CERTID, regCtrl)
OSSL_CRMF_CERTID *OSSL_CRMF_CERTID_gen(const X509_NAME *issuer,
const ASN1_INTEGER *serial)
{
OSSL_CRMF_CERTID *cid = NULL;
if (issuer == NULL || serial == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_CERTID_GEN, CRMF_R_NULL_ARGUMENT);
return NULL;
}
if ((cid = OSSL_CRMF_CERTID_new()) == NULL)
goto err;
if (!X509_NAME_set(&cid->issuer->d.directoryName, issuer))
goto err;
cid->issuer->type = GEN_DIRNAME;
ASN1_INTEGER_free(cid->serialNumber);
if ((cid->serialNumber = ASN1_INTEGER_dup(serial)) == NULL)
goto err;
return cid;
err:
OSSL_CRMF_CERTID_free(cid);
return NULL;
}
/*
* id-regCtrl-protocolEncrKey Control (section 6.6)
*/
IMPLEMENT_CRMF_CTRL_FUNC(protocolEncrKey, X509_PUBKEY, regCtrl)
/*-
* Pushes the attribute given in regInfo in to the CertReqMsg->regInfo stack.
* (section 7)
* returns 1 on success, 0 on error
*/
static int OSSL_CRMF_MSG_push0_regInfo(OSSL_CRMF_MSG *crm,
OSSL_CRMF_ATTRIBUTETYPEANDVALUE *ri)
{
STACK_OF(OSSL_CRMF_ATTRIBUTETYPEANDVALUE) *info = NULL;
if (crm == NULL || ri == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_MSG_PUSH0_REGINFO, CRMF_R_NULL_ARGUMENT);
return 0;
}
if (crm->regInfo == NULL)
crm->regInfo = info = sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_new_null();
if (crm->regInfo == NULL)
goto err;
if (!sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_push(crm->regInfo, ri))
goto err;
return 1;
err:
if (info != NULL)
crm->regInfo = NULL;
sk_OSSL_CRMF_ATTRIBUTETYPEANDVALUE_free(info);
return 0;
}
/* id-regInfo-utf8Pairs to regInfo (section 7.1) */
IMPLEMENT_CRMF_CTRL_FUNC(utf8Pairs, ASN1_UTF8STRING, regInfo)
/* id-regInfo-certReq to regInfo (section 7.2) */
IMPLEMENT_CRMF_CTRL_FUNC(certReq, OSSL_CRMF_CERTREQUEST, regInfo)
/* retrieves the certificate template of crm */
OSSL_CRMF_CERTTEMPLATE *OSSL_CRMF_MSG_get0_tmpl(const OSSL_CRMF_MSG *crm)
{
if (crm == NULL || crm->certReq == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_MSG_GET0_TMPL, CRMF_R_NULL_ARGUMENT);
return NULL;
}
return crm->certReq->certTemplate;
}
int OSSL_CRMF_MSG_set_validity(OSSL_CRMF_MSG *crm, time_t from, time_t to)
{
OSSL_CRMF_OPTIONALVALIDITY *vld = NULL;
ASN1_TIME *from_asn = NULL;
ASN1_TIME *to_asn = NULL;
OSSL_CRMF_CERTTEMPLATE *tmpl = OSSL_CRMF_MSG_get0_tmpl(crm);
if (tmpl == NULL) { /* also crm == NULL implies this */
CRMFerr(CRMF_F_OSSL_CRMF_MSG_SET_VALIDITY, CRMF_R_NULL_ARGUMENT);
return 0;
}
if (from != 0 && ((from_asn = ASN1_TIME_set(NULL, from)) == NULL))
goto err;
if (to != 0 && ((to_asn = ASN1_TIME_set(NULL, to)) == NULL))
goto err;
if ((vld = OSSL_CRMF_OPTIONALVALIDITY_new()) == NULL)
goto err;
vld->notBefore = from_asn;
vld->notAfter = to_asn;
tmpl->validity = vld;
return 1;
err:
ASN1_TIME_free(from_asn);
ASN1_TIME_free(to_asn);
return 0;
}
int OSSL_CRMF_MSG_set_certReqId(OSSL_CRMF_MSG *crm, int rid)
{
if (crm == NULL || crm->certReq == NULL || crm->certReq->certReqId == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_MSG_SET_CERTREQID, CRMF_R_NULL_ARGUMENT);
return 0;
}
return ASN1_INTEGER_set(crm->certReq->certReqId, rid);
}
/* get ASN.1 encoded integer, return -1 on error */
static int crmf_asn1_get_int(const ASN1_INTEGER *a)
{
int64_t res;
if (!ASN1_INTEGER_get_int64(&res, a)) {
CRMFerr(0, ASN1_R_INVALID_NUMBER);
return -1;
}
if (res < INT_MIN) {
CRMFerr(0, ASN1_R_TOO_SMALL);
return -1;
}
if (res > INT_MAX) {
CRMFerr(0, ASN1_R_TOO_LARGE);
return -1;
}
return (int)res;
}
int OSSL_CRMF_MSG_get_certReqId(const OSSL_CRMF_MSG *crm)
{
if (crm == NULL || /* not really needed: */ crm->certReq == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_MSG_GET_CERTREQID, CRMF_R_NULL_ARGUMENT);
return -1;
}
return crmf_asn1_get_int(crm->certReq->certReqId);
}
int OSSL_CRMF_MSG_set0_extensions(OSSL_CRMF_MSG *crm,
X509_EXTENSIONS *exts)
{
OSSL_CRMF_CERTTEMPLATE *tmpl = OSSL_CRMF_MSG_get0_tmpl(crm);
if (tmpl == NULL) { /* also crm == NULL implies this */
CRMFerr(CRMF_F_OSSL_CRMF_MSG_SET0_EXTENSIONS, CRMF_R_NULL_ARGUMENT);
return 0;
}
if (sk_X509_EXTENSION_num(exts) == 0) {
sk_X509_EXTENSION_free(exts);
exts = NULL; /* do not include empty extensions list */
}
sk_X509_EXTENSION_pop_free(tmpl->extensions, X509_EXTENSION_free);
tmpl->extensions = exts;
return 1;
}
int OSSL_CRMF_MSG_push0_extension(OSSL_CRMF_MSG *crm,
X509_EXTENSION *ext)
{
int new = 0;
OSSL_CRMF_CERTTEMPLATE *tmpl = OSSL_CRMF_MSG_get0_tmpl(crm);
if (tmpl == NULL || ext == NULL) { /* also crm == NULL implies this */
CRMFerr(CRMF_F_OSSL_CRMF_MSG_PUSH0_EXTENSION, CRMF_R_NULL_ARGUMENT);
return 0;
}
if (tmpl->extensions == NULL) {
if ((tmpl->extensions = sk_X509_EXTENSION_new_null()) == NULL)
goto err;
new = 1;
}
if (!sk_X509_EXTENSION_push(tmpl->extensions, ext))
goto err;
return 1;
err:
if (new != 0) {
sk_X509_EXTENSION_free(tmpl->extensions);
tmpl->extensions = NULL;
}
return 0;
}
/* TODO: support cases 1+2 (besides case 3) defined in RFC 4211, section 4.1. */
static int CRMF_poposigningkey_init(OSSL_CRMF_POPOSIGNINGKEY *ps,
OSSL_CRMF_CERTREQUEST *cr,
EVP_PKEY *pkey, int dgst)
{
int ret = 0;
EVP_MD *fetched_md = NULL;
const EVP_MD *md = EVP_get_digestbynid(dgst);
if (ps == NULL || cr == NULL || pkey == NULL) {
CRMFerr(CRMF_F_CRMF_POPOSIGNINGKEY_INIT, CRMF_R_NULL_ARGUMENT);
return 0;
}
/* If we didn't find legacy MD, we try an implicit fetch */
if (md == NULL)
md = fetched_md = EVP_MD_fetch(NULL, OBJ_nid2sn(dgst), NULL);
if (md == NULL) {
CRMFerr(CRMF_F_CRMF_POPOSIGNINGKEY_INIT,
CRMF_R_UNSUPPORTED_ALG_FOR_POPSIGNINGKEY);
return 0;
}
ret = ASN1_item_sign(ASN1_ITEM_rptr(OSSL_CRMF_CERTREQUEST),
ps->algorithmIdentifier, NULL, ps->signature,
cr, pkey, md);
EVP_MD_free(fetched_md);
return ret;
}
int OSSL_CRMF_MSG_create_popo(OSSL_CRMF_MSG *crm, EVP_PKEY *pkey,
int dgst, int ppmtd)
{
OSSL_CRMF_POPO *pp = NULL;
ASN1_INTEGER *tag = NULL;
if (crm == NULL || (ppmtd == OSSL_CRMF_POPO_SIGNATURE && pkey == NULL)) {
CRMFerr(CRMF_F_OSSL_CRMF_MSG_CREATE_POPO, CRMF_R_NULL_ARGUMENT);
return 0;
}
if (ppmtd == OSSL_CRMF_POPO_NONE)
goto end;
if ((pp = OSSL_CRMF_POPO_new()) == NULL)
goto err;
pp->type = ppmtd;
switch (ppmtd) {
case OSSL_CRMF_POPO_RAVERIFIED:
if ((pp->value.raVerified = ASN1_NULL_new()) == NULL)
goto err;
break;
case OSSL_CRMF_POPO_SIGNATURE:
{
OSSL_CRMF_POPOSIGNINGKEY *ps = OSSL_CRMF_POPOSIGNINGKEY_new();
if (ps == NULL
|| !CRMF_poposigningkey_init(ps, crm->certReq, pkey, dgst)) {
OSSL_CRMF_POPOSIGNINGKEY_free(ps);
goto err;
}
pp->value.signature = ps;
}
break;
case OSSL_CRMF_POPO_KEYENC:
if ((pp->value.keyEncipherment = OSSL_CRMF_POPOPRIVKEY_new()) == NULL)
goto err;
tag = ASN1_INTEGER_new();
pp->value.keyEncipherment->type =
OSSL_CRMF_POPOPRIVKEY_SUBSEQUENTMESSAGE;
pp->value.keyEncipherment->value.subsequentMessage = tag;
if (tag == NULL
|| !ASN1_INTEGER_set(tag, OSSL_CRMF_SUBSEQUENTMESSAGE_ENCRCERT))
goto err;
break;
default:
CRMFerr(CRMF_F_OSSL_CRMF_MSG_CREATE_POPO,
CRMF_R_UNSUPPORTED_METHOD_FOR_CREATING_POPO);
goto err;
}
end:
OSSL_CRMF_POPO_free(crm->popo);
crm->popo = pp;
return 1;
err:
OSSL_CRMF_POPO_free(pp);
return 0;
}
/* returns 0 for equal, -1 for a < b or error on a, 1 for a > b or error on b */
static int X509_PUBKEY_cmp(X509_PUBKEY *a, X509_PUBKEY *b)
{
X509_ALGOR *algA = NULL, *algB = NULL;
int res = 0;
if (a == b)
return 0;
if (a == NULL || !X509_PUBKEY_get0_param(NULL, NULL, NULL, &algA, a)
|| algA == NULL)
return -1;
if (b == NULL || !X509_PUBKEY_get0_param(NULL, NULL, NULL, &algB, b)
|| algB == NULL)
return 1;
if ((res = X509_ALGOR_cmp(algA, algB)) != 0)
return res;
return EVP_PKEY_cmp(X509_PUBKEY_get0(a), X509_PUBKEY_get0(b));
}
/* verifies the Proof-of-Possession of the request with the given rid in reqs */
int OSSL_CRMF_MSGS_verify_popo(const OSSL_CRMF_MSGS *reqs,
int rid, int acceptRAVerified)
{
OSSL_CRMF_MSG *req = NULL;
X509_PUBKEY *pubkey = NULL;
OSSL_CRMF_POPOSIGNINGKEY *sig = NULL;
if (reqs == NULL || (req = sk_OSSL_CRMF_MSG_value(reqs, rid)) == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_MSGS_VERIFY_POPO, CRMF_R_NULL_ARGUMENT);
return 0;
}
if (req->popo == NULL) {
CRMFerr(0, CRMF_R_POPO_MISSING);
return 0;
}
switch (req->popo->type) {
case OSSL_CRMF_POPO_RAVERIFIED:
if (!acceptRAVerified) {
CRMFerr(0, CRMF_R_POPO_RAVERIFIED_NOT_ACCEPTED);
return 0;
}
break;
case OSSL_CRMF_POPO_SIGNATURE:
pubkey = req->certReq->certTemplate->publicKey;
if (pubkey == NULL) {
CRMFerr(0, CRMF_R_POPO_MISSING_PUBLIC_KEY);
return 0;
}
sig = req->popo->value.signature;
if (sig->poposkInput != NULL) {
/*
* According to RFC 4211: publicKey contains a copy of
* the public key from the certificate template. This MUST be
* exactly the same value as contained in the certificate template.
*/
if (sig->poposkInput->publicKey == NULL) {
CRMFerr(0, CRMF_R_POPO_MISSING_PUBLIC_KEY);
return 0;
}
if (X509_PUBKEY_cmp(pubkey, sig->poposkInput->publicKey) != 0) {
CRMFerr(0, CRMF_R_POPO_INCONSISTENT_PUBLIC_KEY);
return 0;
}
/*
* TODO check the contents of the authInfo sub-field,
* see RFC 4211 https://tools.ietf.org/html/rfc4211#section-4.1
*/
if (ASN1_item_verify(ASN1_ITEM_rptr(OSSL_CRMF_POPOSIGNINGKEYINPUT),
sig->algorithmIdentifier, sig->signature,
sig->poposkInput,
X509_PUBKEY_get0(pubkey)) < 1)
return 0;
} else {
if (req->certReq->certTemplate->subject == NULL) {
CRMFerr(0, CRMF_R_POPO_MISSING_SUBJECT);
return 0;
}
if (ASN1_item_verify(ASN1_ITEM_rptr(OSSL_CRMF_CERTREQUEST),
sig->algorithmIdentifier, sig->signature,
req->certReq, X509_PUBKEY_get0(pubkey)) < 1)
return 0;
}
break;
case OSSL_CRMF_POPO_KEYENC:
/*
* TODO: when OSSL_CMP_certrep_new() supports encrypted certs,
* return 1 if the type of req->popo->value.keyEncipherment
* is OSSL_CRMF_POPOPRIVKEY_SUBSEQUENTMESSAGE and
* its value.subsequentMessage == OSSL_CRMF_SUBSEQUENTMESSAGE_ENCRCERT
*/
case OSSL_CRMF_POPO_KEYAGREE:
default:
CRMFerr(CRMF_F_OSSL_CRMF_MSGS_VERIFY_POPO,
CRMF_R_UNSUPPORTED_POPO_METHOD);
return 0;
}
return 1;
}
/* retrieves the serialNumber of the given cert template or NULL on error */
ASN1_INTEGER
*OSSL_CRMF_CERTTEMPLATE_get0_serialNumber(const OSSL_CRMF_CERTTEMPLATE *tmpl)
{
return tmpl != NULL ? tmpl->serialNumber : NULL;
}
/* retrieves the issuer name of the given cert template or NULL on error */
const X509_NAME
*OSSL_CRMF_CERTTEMPLATE_get0_issuer(const OSSL_CRMF_CERTTEMPLATE *tmpl)
{
return tmpl != NULL ? tmpl->issuer : NULL;
}
/* retrieves the issuer name of the given CertId or NULL on error */
const X509_NAME *OSSL_CRMF_CERTID_get0_issuer(const OSSL_CRMF_CERTID *cid)
{
return cid != NULL && cid->issuer->type == GEN_DIRNAME ?
cid->issuer->d.directoryName : NULL;
}
/* retrieves the serialNumber of the given CertId or NULL on error */
ASN1_INTEGER *OSSL_CRMF_CERTID_get0_serialNumber(const OSSL_CRMF_CERTID *cid)
{
return cid != NULL ? cid->serialNumber : NULL;
}
/*-
* fill in certificate template.
* Any value argument that is NULL will leave the respective field unchanged.
*/
int OSSL_CRMF_CERTTEMPLATE_fill(OSSL_CRMF_CERTTEMPLATE *tmpl,
EVP_PKEY *pubkey,
const X509_NAME *subject,
const X509_NAME *issuer,
const ASN1_INTEGER *serial)
{
if (tmpl == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_CERTTEMPLATE_FILL, CRMF_R_NULL_ARGUMENT);
return 0;
}
if (subject != NULL && !X509_NAME_set((X509_NAME **)&tmpl->subject, subject))
return 0;
if (issuer != NULL && !X509_NAME_set((X509_NAME **)&tmpl->issuer, issuer))
return 0;
if (serial != NULL) {
ASN1_INTEGER_free(tmpl->serialNumber);
if ((tmpl->serialNumber = ASN1_INTEGER_dup(serial)) == NULL)
return 0;
}
if (pubkey != NULL && !X509_PUBKEY_set(&tmpl->publicKey, pubkey))
return 0;
return 1;
}
/*-
* Decrypts the certificate in the given encryptedValue using private key pkey.
* This is needed for the indirect PoP method as in RFC 4210 section 5.2.8.2.
*
* returns a pointer to the decrypted certificate
* returns NULL on error or if no certificate available
*/
X509 *OSSL_CRMF_ENCRYPTEDVALUE_get1_encCert(const OSSL_CRMF_ENCRYPTEDVALUE *ecert,
EVP_PKEY *pkey)
{
X509 *cert = NULL; /* decrypted certificate */
EVP_CIPHER_CTX *evp_ctx = NULL; /* context for symmetric encryption */
unsigned char *ek = NULL; /* decrypted symmetric encryption key */
size_t eksize = 0; /* size of decrypted symmetric encryption key */
const EVP_CIPHER *cipher = NULL; /* used cipher */
int cikeysize = 0; /* key size from cipher */
unsigned char *iv = NULL; /* initial vector for symmetric encryption */
unsigned char *outbuf = NULL; /* decryption output buffer */
const unsigned char *p = NULL; /* needed for decoding ASN1 */
int symmAlg = 0; /* NIDs for symmetric algorithm */
int n, outlen = 0;
EVP_PKEY_CTX *pkctx = NULL; /* private key context */
if (ecert == NULL || ecert->symmAlg == NULL || ecert->encSymmKey == NULL
|| ecert->encValue == NULL || pkey == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_ENCRYPTEDVALUE_GET1_ENCCERT,
CRMF_R_NULL_ARGUMENT);
return NULL;
}
if ((symmAlg = OBJ_obj2nid(ecert->symmAlg->algorithm)) == 0) {
CRMFerr(CRMF_F_OSSL_CRMF_ENCRYPTEDVALUE_GET1_ENCCERT,
CRMF_R_UNSUPPORTED_CIPHER);
return NULL;
}
/* select symmetric cipher based on algorithm given in message */
if ((cipher = EVP_get_cipherbynid(symmAlg)) == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_ENCRYPTEDVALUE_GET1_ENCCERT,
CRMF_R_UNSUPPORTED_CIPHER);
goto end;
}
cikeysize = EVP_CIPHER_key_length(cipher);
/* first the symmetric key needs to be decrypted */
pkctx = EVP_PKEY_CTX_new(pkey, NULL);
if (pkctx != NULL && EVP_PKEY_decrypt_init(pkctx)) {
ASN1_BIT_STRING *encKey = ecert->encSymmKey;
size_t failure;
int retval;
if (EVP_PKEY_decrypt(pkctx, NULL, &eksize,
encKey->data, encKey->length) <= 0
|| (ek = OPENSSL_malloc(eksize)) == NULL)
goto end;
retval = EVP_PKEY_decrypt(pkctx, ek, &eksize,
encKey->data, encKey->length);
ERR_clear_error(); /* error state may have sensitive information */
failure = ~constant_time_is_zero_s(constant_time_msb(retval)
| constant_time_is_zero(retval));
failure |= ~constant_time_eq_s(eksize, (size_t)cikeysize);
if (failure) {
CRMFerr(CRMF_F_OSSL_CRMF_ENCRYPTEDVALUE_GET1_ENCCERT,
CRMF_R_ERROR_DECRYPTING_SYMMETRIC_KEY);
goto end;
}
} else {
goto end;
}
if ((iv = OPENSSL_malloc(EVP_CIPHER_iv_length(cipher))) == NULL)
goto end;
if (ASN1_TYPE_get_octetstring(ecert->symmAlg->parameter, iv,
EVP_CIPHER_iv_length(cipher))
!= EVP_CIPHER_iv_length(cipher)) {
CRMFerr(CRMF_F_OSSL_CRMF_ENCRYPTEDVALUE_GET1_ENCCERT,
CRMF_R_MALFORMED_IV);
goto end;
}
/*
* d2i_X509 changes the given pointer, so use p for decoding the message and
* keep the original pointer in outbuf so the memory can be freed later
*/
if ((p = outbuf = OPENSSL_malloc(ecert->encValue->length +
EVP_CIPHER_block_size(cipher))) == NULL
|| (evp_ctx = EVP_CIPHER_CTX_new()) == NULL)
goto end;
EVP_CIPHER_CTX_set_padding(evp_ctx, 0);
if (!EVP_DecryptInit(evp_ctx, cipher, ek, iv)
|| !EVP_DecryptUpdate(evp_ctx, outbuf, &outlen,
ecert->encValue->data,
ecert->encValue->length)
|| !EVP_DecryptFinal(evp_ctx, outbuf + outlen, &n)) {
CRMFerr(CRMF_F_OSSL_CRMF_ENCRYPTEDVALUE_GET1_ENCCERT,
CRMF_R_ERROR_DECRYPTING_CERTIFICATE);
goto end;
}
outlen += n;
/* convert decrypted certificate from DER to internal ASN.1 structure */
if ((cert = d2i_X509(NULL, &p, outlen)) == NULL) {
CRMFerr(CRMF_F_OSSL_CRMF_ENCRYPTEDVALUE_GET1_ENCCERT,
CRMF_R_ERROR_DECODING_CERTIFICATE);
}
end:
EVP_PKEY_CTX_free(pkctx);
OPENSSL_free(outbuf);
EVP_CIPHER_CTX_free(evp_ctx);
OPENSSL_clear_free(ek, eksize);
OPENSSL_free(iv);
return cert;
}
