Remove X509_REQ_to_X509.

Update-Note: This removes a function that appears to be unused. It also
hardcodes the use of MD5, so please do not use it.

Change-Id: I67909c6360e4737fc22742592f88b907eb818e96
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/45964
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
diff --git a/crypto/CMakeLists.txt b/crypto/CMakeLists.txt
index cde92b5..c06cbb7 100644
--- a/crypto/CMakeLists.txt
+++ b/crypto/CMakeLists.txt
@@ -370,7 +370,6 @@
   x509/x509_ext.c
   x509/x509_lu.c
   x509/x509_obj.c
-  x509/x509_r2x.c
   x509/x509_req.c
   x509/x509_set.c
   x509/x509_trs.c
diff --git a/crypto/x509/x509_r2x.c b/crypto/x509/x509_r2x.c
deleted file mode 100644
index a44b172..0000000
--- a/crypto/x509/x509_r2x.c
+++ /dev/null
@@ -1,116 +0,0 @@
-/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
- *
- * This package is an SSL implementation written
- * by Eric Young (eay@cryptsoft.com).
- * The implementation was written so as to conform with Netscapes SSL.
- *
- * This library is free for commercial and non-commercial use as long as
- * the following conditions are aheared to.  The following conditions
- * apply to all code found in this distribution, be it the RC4, RSA,
- * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
- * included with this distribution is covered by the same copyright terms
- * except that the holder is Tim Hudson (tjh@cryptsoft.com).
- *
- * Copyright remains Eric Young's, and as such any Copyright notices in
- * the code are not to be removed.
- * If this package is used in a product, Eric Young should be given attribution
- * as the author of the parts of the library used.
- * This can be in the form of a textual message at program startup or
- * in documentation (online or textual) provided with the package.
- *
- * 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 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 acknowledgement:
- *    "This product includes cryptographic software written by
- *     Eric Young (eay@cryptsoft.com)"
- *    The word 'cryptographic' can be left out if the rouines from the library
- *    being used are not cryptographic related :-).
- * 4. If you include any Windows specific code (or a derivative thereof) from
- *    the apps directory (application code) you must include an acknowledgement:
- *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
- *
- * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
- * ANY EXPRESS 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 AUTHOR OR 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.
- *
- * The licence and distribution terms for any publically available version or
- * derivative of this code cannot be changed.  i.e. this code cannot simply be
- * copied and put under another distribution licence
- * [including the GNU Public Licence.] */
-
-#include <openssl/asn1.h>
-#include <openssl/bn.h>
-#include <openssl/digest.h>
-#include <openssl/err.h>
-#include <openssl/evp.h>
-#include <openssl/obj.h>
-#include <openssl/x509.h>
-
-X509 *X509_REQ_to_X509(X509_REQ *r, int days, EVP_PKEY *pkey)
-{
-    X509 *ret = NULL;
-    X509_CINF *xi = NULL;
-    X509_NAME *xn;
-    EVP_PKEY *pubkey = NULL;
-    int res;
-
-    if ((ret = X509_new()) == NULL) {
-        OPENSSL_PUT_ERROR(X509, ERR_R_MALLOC_FAILURE);
-        return NULL;
-    }
-
-    /* duplicate the request */
-    xi = ret->cert_info;
-
-    if (sk_X509_ATTRIBUTE_num(r->req_info->attributes) != 0) {
-        if ((xi->version = ASN1_INTEGER_new()) == NULL)
-            goto err;
-        if (!ASN1_INTEGER_set(xi->version, 2))
-            goto err;
-        /*
-         * xi->extensions=ri->attributes; <- bad, should not ever be done
-         * ri->attributes=NULL;
-         */
-    }
-
-    xn = X509_REQ_get_subject_name(r);
-    if (X509_set_subject_name(ret, xn) == 0)
-        goto err;
-    if (X509_set_issuer_name(ret, xn) == 0)
-        goto err;
-
-    if (X509_gmtime_adj(xi->validity->notBefore, 0) == NULL)
-        goto err;
-    if (X509_gmtime_adj(xi->validity->notAfter, (long)60 * 60 * 24 * days) ==
-        NULL)
-        goto err;
-
-    pubkey = X509_REQ_get_pubkey(r);
-    res = X509_set_pubkey(ret, pubkey);
-    EVP_PKEY_free(pubkey);
-
-    if (!res || !X509_sign(ret, pkey, EVP_md5()))
-        goto err;
-    if (0) {
- err:
-        X509_free(ret);
-        ret = NULL;
-    }
-    return (ret);
-}
diff --git a/include/openssl/x509.h b/include/openssl/x509.h
index 357cf91..53a2568 100644
--- a/include/openssl/x509.h
+++ b/include/openssl/x509.h
@@ -941,7 +941,6 @@
 
 OPENSSL_EXPORT X509_REQ *X509_to_X509_REQ(X509 *x, EVP_PKEY *pkey,
                                           const EVP_MD *md);
-OPENSSL_EXPORT X509 *X509_REQ_to_X509(X509_REQ *r, int days, EVP_PKEY *pkey);
 
 DECLARE_ASN1_ENCODE_FUNCTIONS(X509_ALGORS, X509_ALGORS, X509_ALGORS)
 DECLARE_ASN1_FUNCTIONS(X509_VAL)