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-rwxr-xr-xopenssl/crypto/dh/dh_kdf.c187
1 files changed, 187 insertions, 0 deletions
diff --git a/openssl/crypto/dh/dh_kdf.c b/openssl/crypto/dh/dh_kdf.c
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+++ b/openssl/crypto/dh/dh_kdf.c
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+/* crypto/dh/dh_kdf.c */
+/*
+ * Written by Stephen Henson for the OpenSSL project.
+ */
+/* ====================================================================
+ * Copyright (c) 2013 The OpenSSL Project. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ * software must display the following acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ * endorse or promote products derived from this software without
+ * prior written permission. For written permission, please contact
+ * openssl-core@openssl.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ * nor may "OpenSSL" appear in their names without prior written
+ * permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ * acknowledgment:
+ * "This product includes software developed by the OpenSSL Project
+ * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ */
+
+#include <string.h>
+#include <openssl/dh.h>
+#include <openssl/evp.h>
+#include <openssl/asn1.h>
+#include <openssl/cms.h>
+
+/* Key derivation from X9.42/RFC2631 */
+
+#define DH_KDF_MAX (1L << 30)
+
+/* Skip past an ASN1 structure: for OBJECT skip content octets too */
+
+static int skip_asn1(unsigned char **pp, long *plen, int exptag)
+{
+ const unsigned char *q = *pp;
+ int i, tag, xclass;
+ long tmplen;
+ i = ASN1_get_object(&q, &tmplen, &tag, &xclass, *plen);
+ if (i & 0x80)
+ return 0;
+ if (tag != exptag || xclass != V_ASN1_UNIVERSAL)
+ return 0;
+ if (tag == V_ASN1_OBJECT)
+ q += tmplen;
+ *plen -= q - *pp;
+ *pp = (unsigned char *)q;
+ return 1;
+}
+
+/*
+ * Encode the DH shared info structure, return an offset to the counter value
+ * so we can update the structure without reencoding it.
+ */
+
+static int dh_sharedinfo_encode(unsigned char **pder, unsigned char **pctr,
+ ASN1_OBJECT *key_oid, size_t outlen,
+ const unsigned char *ukm, size_t ukmlen)
+{
+ unsigned char *p;
+ int derlen;
+ long tlen;
+ /* "magic" value to check offset is sane */
+ static unsigned char ctr[4] = { 0xF3, 0x17, 0x22, 0x53 };
+ X509_ALGOR atmp;
+ ASN1_OCTET_STRING ctr_oct, ukm_oct, *pukm_oct;
+ ASN1_TYPE ctr_atype;
+ if (ukmlen > DH_KDF_MAX || outlen > DH_KDF_MAX)
+ return 0;
+ ctr_oct.data = ctr;
+ ctr_oct.length = 4;
+ ctr_oct.flags = 0;
+ ctr_oct.type = V_ASN1_OCTET_STRING;
+ ctr_atype.type = V_ASN1_OCTET_STRING;
+ ctr_atype.value.octet_string = &ctr_oct;
+ atmp.algorithm = key_oid;
+ atmp.parameter = &ctr_atype;
+ if (ukm) {
+ ukm_oct.type = V_ASN1_OCTET_STRING;
+ ukm_oct.flags = 0;
+ ukm_oct.data = (unsigned char *)ukm;
+ ukm_oct.length = ukmlen;
+ pukm_oct = &ukm_oct;
+ } else
+ pukm_oct = NULL;
+ derlen = CMS_SharedInfo_encode(pder, &atmp, pukm_oct, outlen);
+ if (derlen <= 0)
+ return 0;
+ p = *pder;
+ tlen = derlen;
+ if (!skip_asn1(&p, &tlen, V_ASN1_SEQUENCE))
+ return 0;
+ if (!skip_asn1(&p, &tlen, V_ASN1_SEQUENCE))
+ return 0;
+ if (!skip_asn1(&p, &tlen, V_ASN1_OBJECT))
+ return 0;
+ if (!skip_asn1(&p, &tlen, V_ASN1_OCTET_STRING))
+ return 0;
+ if (CRYPTO_memcmp(p, ctr, 4))
+ return 0;
+ *pctr = p;
+ return derlen;
+}
+
+int DH_KDF_X9_42(unsigned char *out, size_t outlen,
+ const unsigned char *Z, size_t Zlen,
+ ASN1_OBJECT *key_oid,
+ const unsigned char *ukm, size_t ukmlen, const EVP_MD *md)
+{
+ EVP_MD_CTX mctx;
+ int rv = 0;
+ unsigned int i;
+ size_t mdlen;
+ unsigned char *der = NULL, *ctr;
+ int derlen;
+ if (Zlen > DH_KDF_MAX)
+ return 0;
+ mdlen = EVP_MD_size(md);
+ EVP_MD_CTX_init(&mctx);
+ derlen = dh_sharedinfo_encode(&der, &ctr, key_oid, outlen, ukm, ukmlen);
+ if (derlen == 0)
+ goto err;
+ for (i = 1;; i++) {
+ unsigned char mtmp[EVP_MAX_MD_SIZE];
+ EVP_DigestInit_ex(&mctx, md, NULL);
+ if (!EVP_DigestUpdate(&mctx, Z, Zlen))
+ goto err;
+ ctr[3] = i & 0xFF;
+ ctr[2] = (i >> 8) & 0xFF;
+ ctr[1] = (i >> 16) & 0xFF;
+ ctr[0] = (i >> 24) & 0xFF;
+ if (!EVP_DigestUpdate(&mctx, der, derlen))
+ goto err;
+ if (outlen >= mdlen) {
+ if (!EVP_DigestFinal(&mctx, out, NULL))
+ goto err;
+ outlen -= mdlen;
+ if (outlen == 0)
+ break;
+ out += mdlen;
+ } else {
+ if (!EVP_DigestFinal(&mctx, mtmp, NULL))
+ goto err;
+ memcpy(out, mtmp, outlen);
+ OPENSSL_cleanse(mtmp, mdlen);
+ break;
+ }
+ }
+ rv = 1;
+ err:
+ if (der)
+ OPENSSL_free(der);
+ EVP_MD_CTX_cleanup(&mctx);
+ return rv;
+}