Work towards supporting Cryptographic Message Syntax (CMS) in libcrypto.

Cryptographic Message Syntax (CMS) is a standard for cryptographically
protecting messages, as defined in RFC 5652. It is derived from PKCS #7
version 1.5 and utilises various ASN.1 structures, making it complex and
fairly heavyweight. Various protocols - including RPKI (RFC 6480) - have
been built on top of it, which means it is necessary to support CMS, in
order to support RPKI.

This imports around 6,000 lines of code from OpenSSL 1.1.1, which is still
under the original OpenSSL license. Further work will occur in tree.

Requested by and discussed with many.

ok deraadt@ tb@

1 files changed, 213 insertions, 0 deletions

diff --git a/src/lib/libcrypto/cms/cms_enc.c b/src/lib/libcrypto/cms/cms_enc.c
new file mode 100644
index 0000000000..a1719830e8
--- /dev/null
+++ b/src/lib/libcrypto/cms/cms_enc.c
@@ -0,0 +1,213 @@
+/*
+ * Copyright 2008-2018 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/rand.h>
+#include "cms_lcl.h"
+
+/* CMS EncryptedData Utilities */
+
+/* Return BIO based on EncryptedContentInfo and key */
+
+BIO *cms_EncryptedContent_init_bio(CMS_EncryptedContentInfo *ec)
+{
+    BIO *b;
+    EVP_CIPHER_CTX *ctx;
+    const EVP_CIPHER *ciph;
+    X509_ALGOR *calg = ec->contentEncryptionAlgorithm;
+    unsigned char iv[EVP_MAX_IV_LENGTH], *piv = NULL;
+    unsigned char *tkey = NULL;
+    size_t tkeylen = 0;
+
+    int ok = 0;
+
+    int enc, keep_key = 0;
+
+    enc = ec->cipher ? 1 : 0;
+
+    b = BIO_new(BIO_f_cipher());
+    if (b == NULL) {
+        CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE);
+        return NULL;
+    }
+
+    BIO_get_cipher_ctx(b, &ctx);
+
+    if (enc) {
+        ciph = ec->cipher;
+        /*
+         * If not keeping key set cipher to NULL so subsequent calls decrypt.
+         */
+        if (ec->key)
+            ec->cipher = NULL;
+    } else {
+        ciph = EVP_get_cipherbyobj(calg->algorithm);
+
+        if (!ciph) {
+            CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, CMS_R_UNKNOWN_CIPHER);
+            goto err;
+        }
+    }
+
+    if (EVP_CipherInit_ex(ctx, ciph, NULL, NULL, NULL, enc) <= 0) {
+        CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
+               CMS_R_CIPHER_INITIALISATION_ERROR);
+        goto err;
+    }
+
+    if (enc) {
+        int ivlen;
+        calg->algorithm = OBJ_nid2obj(EVP_CIPHER_CTX_type(ctx));
+        /* Generate a random IV if we need one */
+        ivlen = EVP_CIPHER_CTX_iv_length(ctx);
+        if (ivlen > 0) {
+            if (RAND_bytes(iv, ivlen) <= 0)
+                goto err;
+            piv = iv;
+        }
+    } else if (EVP_CIPHER_asn1_to_param(ctx, calg->parameter) <= 0) {
+        CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
+               CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
+        goto err;
+    }
+    tkeylen = EVP_CIPHER_CTX_key_length(ctx);
+    /* Generate random session key */
+    if (!enc || !ec->key) {
+        tkey = OPENSSL_malloc(tkeylen);
+        if (tkey == NULL) {
+            CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE);
+            goto err;
+        }
+        if (EVP_CIPHER_CTX_rand_key(ctx, tkey) <= 0)
+            goto err;
+    }
+
+    if (!ec->key) {
+        ec->key = tkey;
+        ec->keylen = tkeylen;
+        tkey = NULL;
+        if (enc)
+            keep_key = 1;
+        else
+            ERR_clear_error();
+
+    }
+
+    if (ec->keylen != tkeylen) {
+        /* If necessary set key length */
+        if (EVP_CIPHER_CTX_set_key_length(ctx, ec->keylen) <= 0) {
+            /*
+             * Only reveal failure if debugging so we don't leak information
+             * which may be useful in MMA.
+             */
+            if (enc || ec->debug) {
+                CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
+                       CMS_R_INVALID_KEY_LENGTH);
+                goto err;
+            } else {
+                /* Use random key */
+                OPENSSL_clear_free(ec->key, ec->keylen);
+                ec->key = tkey;
+                ec->keylen = tkeylen;
+                tkey = NULL;
+                ERR_clear_error();
+            }
+        }
+    }
+
+    if (EVP_CipherInit_ex(ctx, NULL, NULL, ec->key, piv, enc) <= 0) {
+        CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
+               CMS_R_CIPHER_INITIALISATION_ERROR);
+        goto err;
+    }
+    if (enc) {
+        calg->parameter = ASN1_TYPE_new();
+        if (calg->parameter == NULL) {
+            CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO, ERR_R_MALLOC_FAILURE);
+            goto err;
+        }
+        if (EVP_CIPHER_param_to_asn1(ctx, calg->parameter) <= 0) {
+            CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT_BIO,
+                   CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
+            goto err;
+        }
+        /* If parameter type not set omit parameter */
+        if (calg->parameter->type == V_ASN1_UNDEF) {
+            ASN1_TYPE_free(calg->parameter);
+            calg->parameter = NULL;
+        }
+    }
+    ok = 1;
+
+ err:
+    if (!keep_key || !ok) {
+        OPENSSL_clear_free(ec->key, ec->keylen);
+        ec->key = NULL;
+    }
+    OPENSSL_clear_free(tkey, tkeylen);
+    if (ok)
+        return b;
+    BIO_free(b);
+    return NULL;
+}
+
+int cms_EncryptedContent_init(CMS_EncryptedContentInfo *ec,
+                              const EVP_CIPHER *cipher,
+                              const unsigned char *key, size_t keylen)
+{
+    ec->cipher = cipher;
+    if (key) {
+        if ((ec->key = OPENSSL_malloc(keylen)) == NULL) {
+            CMSerr(CMS_F_CMS_ENCRYPTEDCONTENT_INIT, ERR_R_MALLOC_FAILURE);
+            return 0;
+        }
+        memcpy(ec->key, key, keylen);
+    }
+    ec->keylen = keylen;
+    if (cipher)
+        ec->contentType = OBJ_nid2obj(NID_pkcs7_data);
+    return 1;
+}
+
+int CMS_EncryptedData_set1_key(CMS_ContentInfo *cms, const EVP_CIPHER *ciph,
+                               const unsigned char *key, size_t keylen)
+{
+    CMS_EncryptedContentInfo *ec;
+    if (!key || !keylen) {
+        CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, CMS_R_NO_KEY);
+        return 0;
+    }
+    if (ciph) {
+        cms->d.encryptedData = M_ASN1_new_of(CMS_EncryptedData);
+        if (!cms->d.encryptedData) {
+            CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, ERR_R_MALLOC_FAILURE);
+            return 0;
+        }
+        cms->contentType = OBJ_nid2obj(NID_pkcs7_encrypted);
+        cms->d.encryptedData->version = 0;
+    } else if (OBJ_obj2nid(cms->contentType) != NID_pkcs7_encrypted) {
+        CMSerr(CMS_F_CMS_ENCRYPTEDDATA_SET1_KEY, CMS_R_NOT_ENCRYPTED_DATA);
+        return 0;
+    }
+    ec = cms->d.encryptedData->encryptedContentInfo;
+    return cms_EncryptedContent_init(ec, ciph, key, keylen);
+}
+
+BIO *cms_EncryptedData_init_bio(CMS_ContentInfo *cms)
+{
+    CMS_EncryptedData *enc = cms->d.encryptedData;
+    if (enc->encryptedContentInfo->cipher && enc->unprotectedAttrs)
+        enc->version = 2;
+    return cms_EncryptedContent_init_bio(enc->encryptedContentInfo);
+}