/* Certificate request creation. Demonstrates some request related
 * operations.
 */

#include <stdio.h>
#include <stdlib.h>

#include <openssl/pem.h>
#include <openssl/conf.h>
#include <openssl/x509v3.h>
#ifndef OPENSSL_NO_ENGINE
#include <openssl/engine.h>
#endif

int mkreq(X509_REQ **x509p, EVP_PKEY **pkeyp, int bits, int serial, int days);
int add_ext(STACK_OF(X509_REQUEST) *sk, int nid, char *value);

int main(int argc, char **argv)
	{
	BIO *bio_err;
	X509_REQ *req=NULL;
	EVP_PKEY *pkey=NULL;

	CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ON);

	bio_err=BIO_new_fp(stderr, BIO_NOCLOSE);

	mkreq(&req,&pkey,512,0,365);

	RSA_print_fp(stdout,pkey->pkey.rsa,0);
	X509_REQ_print_fp(stdout,req);

	PEM_write_X509_REQ(stdout,req);

	X509_REQ_free(req);
	EVP_PKEY_free(pkey);

#ifndef OPENSSL_NO_ENGINE
	ENGINE_cleanup();
#endif
	CRYPTO_cleanup_all_ex_data();

	CRYPTO_mem_leaks(bio_err);
	BIO_free(bio_err);
	return(0);
	}

static void callback(int p, int n, void *arg)
	{
	char c='B';

	if (p == 0) c='.';
	if (p == 1) c='+';
	if (p == 2) c='*';
	if (p == 3) c='\n';
	fputc(c,stderr);
	}

int mkreq(X509_REQ **req, EVP_PKEY **pkeyp, int bits, int serial, int days)
	{
	X509_REQ *x;
	EVP_PKEY *pk;
	RSA *rsa;
	X509_NAME *name=NULL;
	STACK_OF(X509_EXTENSION) *exts = NULL;
	
	if ((pk=EVP_PKEY_new()) == NULL)
		goto err;

	if ((x=X509_REQ_new()) == NULL)
		goto err;

	rsa=RSA_generate_key(bits,RSA_F4,callback,NULL);
	if (!EVP_PKEY_assign_RSA(pk,rsa))
		goto err;

	rsa=NULL;

	X509_REQ_set_pubkey(x,pk);

	name=X509_REQ_get_subject_name(x);

	/* This function creates and adds the entry, working out the
	 * correct string type and performing checks on its length.
	 * Normally we'd check the return value for errors...
	 */
	X509_NAME_add_entry_by_txt(name,"C",
				MBSTRING_ASC, "UK", -1, -1, 0);
	X509_NAME_add_entry_by_txt(name,"CN",
				MBSTRING_ASC, "OpenSSL Group", -1, -1, 0);

#ifdef REQUEST_EXTENSIONS
	/* Certificate requests can contain extensions, which can be used
	 * to indicate the extensions the requestor would like added to 
	 * their certificate. CAs might ignore them however or even choke
	 * if they are present.
	 */

	/* For request extensions they are all packed in a single attribute.
	 * We save them in a STACK and add them all at once later...
	 */

	exts = sk_X509_EXTENSION_new_null();
	/* Standard extenions */

	add_ext(exts, NID_key_usage, "critical,digitalSignature,keyEncipherment");

	/* This is a typical use for request extensions: requesting a value for
	 * subject alternative name.
	 */

	add_ext(exts, NID_subject_alt_name, "email:steve@openssl.org");

	/* Some Netscape specific extensions */
	add_ext(exts, NID_netscape_cert_type, "client,email");


#ifdef CUSTOM_EXT
	/* Maybe even add our own extension based on existing */
	{
		int nid;
		nid = OBJ_create("1.2.3.4", "MyAlias", "My Test Alias Extension");
		X509V3_EXT_add_alias(nid, NID_netscape_comment);
		add_ext(x, nid, "example comment alias");
	}
#endif

	/* Now we've created the extensions we add them to the request */

	X509_REQ_add_extensions(x, exts);

	sk_X509_EXTENSION_pop_free(exts, X509_EXTENSION_free);

#endif
	
	if (!X509_REQ_sign(x,pk,EVP_md5()))
		goto err;

	*req=x;
	*pkeyp=pk;
	return(1);
err:
	return(0);
	}

/* Add extension using V3 code: we can set the config file as NULL
 * because we wont reference any other sections.
 */

int add_ext(STACK_OF(X509_REQUEST) *sk, int nid, char *value)
	{
	X509_EXTENSION *ex;
	ex = X509V3_EXT_conf_nid(NULL, NULL, nid, value);
	if (!ex)
		return 0;
	sk_X509_EXTENSION_push(sk, ex);

	return 1;
	}