1 files changed, 414 insertions, 0 deletions

diff --git a/src/lib/libcrypto/cms/cms_kari.c b/src/lib/libcrypto/cms/cms_kari.c
new file mode 100644
index 0000000000..5e83814d0f
--- /dev/null
+++ b/src/lib/libcrypto/cms/cms_kari.c
@@ -0,0 +1,414 @@
+/*
+ * Copyright 2013-2019 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 kari 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 (rek == NULL)
+        return 0;
+
+    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;
+
+}