--- /dev/null
+/*
+ * Copyright 2013-2016 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the OpenSSL license (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
+ */
+
+#include "internal/cryptlib.h"
+#include <openssl/asn1t.h>
+#include <openssl/pem.h>
+#include <openssl/x509v3.h>
+#include <openssl/err.h>
+#include <openssl/cms.h>
+#include <openssl/aes.h>
+#include "cms_lcl.h"
+#include "internal/asn1_int.h"
+
+/* Key Agreement Recipient Info (KARI) routines */
+
+int CMS_RecipientInfo_kari_get0_alg(CMS_RecipientInfo *ri,
+ X509_ALGOR **palg,
+ ASN1_OCTET_STRING **pukm)
+{
+ if (ri->type != CMS_RECIPINFO_AGREE) {
+ CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_GET0_ALG,
+ CMS_R_NOT_KEY_AGREEMENT);
+ return 0;
+ }
+ if (palg)
+ *palg = ri->d.kari->keyEncryptionAlgorithm;
+ if (pukm)
+ *pukm = ri->d.kari->ukm;
+ return 1;
+}
+
+/* Retrieve recipient encrypted keys from a kari */
+
+STACK_OF(CMS_RecipientEncryptedKey)
+*CMS_RecipientInfo_kari_get0_reks(CMS_RecipientInfo *ri)
+{
+ if (ri->type != CMS_RECIPINFO_AGREE) {
+ CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_GET0_REKS,
+ CMS_R_NOT_KEY_AGREEMENT);
+ return NULL;
+ }
+ return ri->d.kari->recipientEncryptedKeys;
+}
+
+int CMS_RecipientInfo_kari_get0_orig_id(CMS_RecipientInfo *ri,
+ X509_ALGOR **pubalg,
+ ASN1_BIT_STRING **pubkey,
+ ASN1_OCTET_STRING **keyid,
+ X509_NAME **issuer,
+ ASN1_INTEGER **sno)
+{
+ CMS_OriginatorIdentifierOrKey *oik;
+ if (ri->type != CMS_RECIPINFO_AGREE) {
+ CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_GET0_ORIG_ID,
+ CMS_R_NOT_KEY_AGREEMENT);
+ return 0;
+ }
+ oik = ri->d.kari->originator;
+ if (issuer)
+ *issuer = NULL;
+ if (sno)
+ *sno = NULL;
+ if (keyid)
+ *keyid = NULL;
+ if (pubalg)
+ *pubalg = NULL;
+ if (pubkey)
+ *pubkey = NULL;
+ if (oik->type == CMS_OIK_ISSUER_SERIAL) {
+ if (issuer)
+ *issuer = oik->d.issuerAndSerialNumber->issuer;
+ if (sno)
+ *sno = oik->d.issuerAndSerialNumber->serialNumber;
+ } else if (oik->type == CMS_OIK_KEYIDENTIFIER) {
+ if (keyid)
+ *keyid = oik->d.subjectKeyIdentifier;
+ } else if (oik->type == CMS_OIK_PUBKEY) {
+ if (pubalg)
+ *pubalg = oik->d.originatorKey->algorithm;
+ if (pubkey)
+ *pubkey = oik->d.originatorKey->publicKey;
+ } else
+ return 0;
+ return 1;
+}
+
+int CMS_RecipientInfo_kari_orig_id_cmp(CMS_RecipientInfo *ri, X509 *cert)
+{
+ CMS_OriginatorIdentifierOrKey *oik;
+ if (ri->type != CMS_RECIPINFO_AGREE) {
+ CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_ORIG_ID_CMP,
+ CMS_R_NOT_KEY_AGREEMENT);
+ return -2;
+ }
+ oik = ri->d.kari->originator;
+ if (oik->type == CMS_OIK_ISSUER_SERIAL)
+ return cms_ias_cert_cmp(oik->d.issuerAndSerialNumber, cert);
+ else if (oik->type == CMS_OIK_KEYIDENTIFIER)
+ return cms_keyid_cert_cmp(oik->d.subjectKeyIdentifier, cert);
+ return -1;
+}
+
+int CMS_RecipientEncryptedKey_get0_id(CMS_RecipientEncryptedKey *rek,
+ ASN1_OCTET_STRING **keyid,
+ ASN1_GENERALIZEDTIME **tm,
+ CMS_OtherKeyAttribute **other,
+ X509_NAME **issuer, ASN1_INTEGER **sno)
+{
+ CMS_KeyAgreeRecipientIdentifier *rid = rek->rid;
+ if (rid->type == CMS_REK_ISSUER_SERIAL) {
+ if (issuer)
+ *issuer = rid->d.issuerAndSerialNumber->issuer;
+ if (sno)
+ *sno = rid->d.issuerAndSerialNumber->serialNumber;
+ if (keyid)
+ *keyid = NULL;
+ if (tm)
+ *tm = NULL;
+ if (other)
+ *other = NULL;
+ } else if (rid->type == CMS_REK_KEYIDENTIFIER) {
+ if (keyid)
+ *keyid = rid->d.rKeyId->subjectKeyIdentifier;
+ if (tm)
+ *tm = rid->d.rKeyId->date;
+ if (other)
+ *other = rid->d.rKeyId->other;
+ if (issuer)
+ *issuer = NULL;
+ if (sno)
+ *sno = NULL;
+ } else
+ return 0;
+ return 1;
+}
+
+int CMS_RecipientEncryptedKey_cert_cmp(CMS_RecipientEncryptedKey *rek,
+ X509 *cert)
+{
+ CMS_KeyAgreeRecipientIdentifier *rid = rek->rid;
+ if (rid->type == CMS_REK_ISSUER_SERIAL)
+ return cms_ias_cert_cmp(rid->d.issuerAndSerialNumber, cert);
+ else if (rid->type == CMS_REK_KEYIDENTIFIER)
+ return cms_keyid_cert_cmp(rid->d.rKeyId->subjectKeyIdentifier, cert);
+ else
+ return -1;
+}
+
+int CMS_RecipientInfo_kari_set0_pkey(CMS_RecipientInfo *ri, EVP_PKEY *pk)
+{
+ EVP_PKEY_CTX *pctx;
+ CMS_KeyAgreeRecipientInfo *kari = ri->d.kari;
+
+ EVP_PKEY_CTX_free(kari->pctx);
+ kari->pctx = NULL;
+ if (!pk)
+ return 1;
+ pctx = EVP_PKEY_CTX_new(pk, NULL);
+ if (!pctx || !EVP_PKEY_derive_init(pctx))
+ goto err;
+ kari->pctx = pctx;
+ return 1;
+ err:
+ EVP_PKEY_CTX_free(pctx);
+ return 0;
+}
+
+EVP_CIPHER_CTX *CMS_RecipientInfo_kari_get0_ctx(CMS_RecipientInfo *ri)
+{
+ if (ri->type == CMS_RECIPINFO_AGREE)
+ return ri->d.kari->ctx;
+ return NULL;
+}
+
+/*
+ * Derive KEK and decrypt/encrypt with it to produce either the original CEK
+ * or the encrypted CEK.
+ */
+
+static int cms_kek_cipher(unsigned char **pout, size_t *poutlen,
+ const unsigned char *in, size_t inlen,
+ CMS_KeyAgreeRecipientInfo *kari, int enc)
+{
+ /* Key encryption key */
+ unsigned char kek[EVP_MAX_KEY_LENGTH];
+ size_t keklen;
+ int rv = 0;
+ unsigned char *out = NULL;
+ int outlen;
+ keklen = EVP_CIPHER_CTX_key_length(kari->ctx);
+ if (keklen > EVP_MAX_KEY_LENGTH)
+ return 0;
+ /* Derive KEK */
+ if (EVP_PKEY_derive(kari->pctx, kek, &keklen) <= 0)
+ goto err;
+ /* Set KEK in context */
+ if (!EVP_CipherInit_ex(kari->ctx, NULL, NULL, kek, NULL, enc))
+ goto err;
+ /* obtain output length of ciphered key */
+ if (!EVP_CipherUpdate(kari->ctx, NULL, &outlen, in, inlen))
+ goto err;
+ out = OPENSSL_malloc(outlen);
+ if (out == NULL)
+ goto err;
+ if (!EVP_CipherUpdate(kari->ctx, out, &outlen, in, inlen))
+ goto err;
+ *pout = out;
+ *poutlen = (size_t)outlen;
+ rv = 1;
+
+ err:
+ OPENSSL_cleanse(kek, keklen);
+ if (!rv)
+ OPENSSL_free(out);
+ EVP_CIPHER_CTX_reset(kari->ctx);
+ /* FIXME: WHY IS kari->pctx freed here? /RL */
+ EVP_PKEY_CTX_free(kari->pctx);
+ kari->pctx = NULL;
+ return rv;
+}
+
+int CMS_RecipientInfo_kari_decrypt(CMS_ContentInfo *cms,
+ CMS_RecipientInfo *ri,
+ CMS_RecipientEncryptedKey *rek)
+{
+ int rv = 0;
+ unsigned char *enckey = NULL, *cek = NULL;
+ size_t enckeylen;
+ size_t ceklen;
+ CMS_EncryptedContentInfo *ec;
+ enckeylen = rek->encryptedKey->length;
+ enckey = rek->encryptedKey->data;
+ /* Setup all parameters to derive KEK */
+ if (!cms_env_asn1_ctrl(ri, 1))
+ goto err;
+ /* Attempt to decrypt CEK */
+ if (!cms_kek_cipher(&cek, &ceklen, enckey, enckeylen, ri->d.kari, 0))
+ goto err;
+ ec = cms->d.envelopedData->encryptedContentInfo;
+ OPENSSL_clear_free(ec->key, ec->keylen);
+ ec->key = cek;
+ ec->keylen = ceklen;
+ cek = NULL;
+ rv = 1;
+ err:
+ OPENSSL_free(cek);
+ return rv;
+}
+
+/* Create ephemeral key and initialise context based on it */
+static int cms_kari_create_ephemeral_key(CMS_KeyAgreeRecipientInfo *kari,
+ EVP_PKEY *pk)
+{
+ EVP_PKEY_CTX *pctx = NULL;
+ EVP_PKEY *ekey = NULL;
+ int rv = 0;
+ pctx = EVP_PKEY_CTX_new(pk, NULL);
+ if (!pctx)
+ goto err;
+ if (EVP_PKEY_keygen_init(pctx) <= 0)
+ goto err;
+ if (EVP_PKEY_keygen(pctx, &ekey) <= 0)
+ goto err;
+ EVP_PKEY_CTX_free(pctx);
+ pctx = EVP_PKEY_CTX_new(ekey, NULL);
+ if (!pctx)
+ goto err;
+ if (EVP_PKEY_derive_init(pctx) <= 0)
+ goto err;
+ kari->pctx = pctx;
+ rv = 1;
+ err:
+ if (!rv)
+ EVP_PKEY_CTX_free(pctx);
+ EVP_PKEY_free(ekey);
+ return rv;
+}
+
+/* Initialise a ktri based on passed certificate and key */
+
+int cms_RecipientInfo_kari_init(CMS_RecipientInfo *ri, X509 *recip,
+ EVP_PKEY *pk, unsigned int flags)
+{
+ CMS_KeyAgreeRecipientInfo *kari;
+ CMS_RecipientEncryptedKey *rek = NULL;
+
+ ri->d.kari = M_ASN1_new_of(CMS_KeyAgreeRecipientInfo);
+ if (!ri->d.kari)
+ return 0;
+ ri->type = CMS_RECIPINFO_AGREE;
+
+ kari = ri->d.kari;
+ kari->version = 3;
+
+ rek = M_ASN1_new_of(CMS_RecipientEncryptedKey);
+ if (!sk_CMS_RecipientEncryptedKey_push(kari->recipientEncryptedKeys, rek)) {
+ M_ASN1_free_of(rek, CMS_RecipientEncryptedKey);
+ return 0;
+ }
+
+ if (flags & CMS_USE_KEYID) {
+ rek->rid->type = CMS_REK_KEYIDENTIFIER;
+ rek->rid->d.rKeyId = M_ASN1_new_of(CMS_RecipientKeyIdentifier);
+ if (rek->rid->d.rKeyId == NULL)
+ return 0;
+ if (!cms_set1_keyid(&rek->rid->d.rKeyId->subjectKeyIdentifier, recip))
+ return 0;
+ } else {
+ rek->rid->type = CMS_REK_ISSUER_SERIAL;
+ if (!cms_set1_ias(&rek->rid->d.issuerAndSerialNumber, recip))
+ return 0;
+ }
+
+ /* Create ephemeral key */
+ if (!cms_kari_create_ephemeral_key(kari, pk))
+ return 0;
+
+ EVP_PKEY_up_ref(pk);
+ rek->pkey = pk;
+ return 1;
+}
+
+static int cms_wrap_init(CMS_KeyAgreeRecipientInfo *kari,
+ const EVP_CIPHER *cipher)
+{
+ EVP_CIPHER_CTX *ctx = kari->ctx;
+ const EVP_CIPHER *kekcipher;
+ int keylen = EVP_CIPHER_key_length(cipher);
+ /* If a suitable wrap algorithm is already set nothing to do */
+ kekcipher = EVP_CIPHER_CTX_cipher(ctx);
+
+ if (kekcipher) {
+ if (EVP_CIPHER_CTX_mode(ctx) != EVP_CIPH_WRAP_MODE)
+ return 0;
+ return 1;
+ }
+ /*
+ * Pick a cipher based on content encryption cipher. If it is DES3 use
+ * DES3 wrap otherwise use AES wrap similar to key size.
+ */
+#ifndef OPENSSL_NO_DES
+ if (EVP_CIPHER_type(cipher) == NID_des_ede3_cbc)
+ kekcipher = EVP_des_ede3_wrap();
+ else
+#endif
+ if (keylen <= 16)
+ kekcipher = EVP_aes_128_wrap();
+ else if (keylen <= 24)
+ kekcipher = EVP_aes_192_wrap();
+ else
+ kekcipher = EVP_aes_256_wrap();
+ return EVP_EncryptInit_ex(ctx, kekcipher, NULL, NULL, NULL);
+}
+
+/* Encrypt content key in key agreement recipient info */
+
+int cms_RecipientInfo_kari_encrypt(CMS_ContentInfo *cms,
+ CMS_RecipientInfo *ri)
+{
+ CMS_KeyAgreeRecipientInfo *kari;
+ CMS_EncryptedContentInfo *ec;
+ CMS_RecipientEncryptedKey *rek;
+ STACK_OF(CMS_RecipientEncryptedKey) *reks;
+ int i;
+
+ if (ri->type != CMS_RECIPINFO_AGREE) {
+ CMSerr(CMS_F_CMS_RECIPIENTINFO_KARI_ENCRYPT, CMS_R_NOT_KEY_AGREEMENT);
+ return 0;
+ }
+ kari = ri->d.kari;
+ reks = kari->recipientEncryptedKeys;
+ ec = cms->d.envelopedData->encryptedContentInfo;
+ /* Initialise wrap algorithm parameters */
+ if (!cms_wrap_init(kari, ec->cipher))
+ return 0;
+ /*
+ * If no originator key set up initialise for ephemeral key the public key
+ * ASN1 structure will set the actual public key value.
+ */
+ if (kari->originator->type == -1) {
+ CMS_OriginatorIdentifierOrKey *oik = kari->originator;
+ oik->type = CMS_OIK_PUBKEY;
+ oik->d.originatorKey = M_ASN1_new_of(CMS_OriginatorPublicKey);
+ if (!oik->d.originatorKey)
+ return 0;
+ }
+ /* Initialise KDF algorithm */
+ if (!cms_env_asn1_ctrl(ri, 0))
+ return 0;
+ /* For each rek, derive KEK, encrypt CEK */
+ for (i = 0; i < sk_CMS_RecipientEncryptedKey_num(reks); i++) {
+ unsigned char *enckey;
+ size_t enckeylen;
+ rek = sk_CMS_RecipientEncryptedKey_value(reks, i);
+ if (EVP_PKEY_derive_set_peer(kari->pctx, rek->pkey) <= 0)
+ return 0;
+ if (!cms_kek_cipher(&enckey, &enckeylen, ec->key, ec->keylen,
+ kari, 1))
+ return 0;
+ ASN1_STRING_set0(rek->encryptedKey, enckey, enckeylen);
+ }
+
+ return 1;
+
+}
projects / cassiopeia.git / blobdiff