diff options
Diffstat (limited to 'openssl/crypto/dh/dh_kdf.c')
| -rwxr-xr-x | openssl/crypto/dh/dh_kdf.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/openssl/crypto/dh/dh_kdf.c b/openssl/crypto/dh/dh_kdf.c new file mode 100755 index 000000000..a882cb286 --- /dev/null +++ b/openssl/crypto/dh/dh_kdf.c @@ -0,0 +1,187 @@ +/* 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; +} |