source: vendor/current/source4/lib/tls/tlscert.c

/* 
   Unix SMB/CIFS implementation.

   auto-generate self signed TLS certificates

   Copyright (C) Andrew Tridgell 2005
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "lib/tls/tls.h"

#if ENABLE_GNUTLS
#include <gnutls/gnutls.h>
#include <gnutls/x509.h>
#if defined(HAVE_GCRYPT_H) && !defined(HAVE_GNUTLS3)
#include <gcrypt.h>
#endif

#define ORGANISATION_NAME "Samba Administration"
#define CA_NAME           "Samba - temporary autogenerated CA certificate"
#define UNIT_NAME         "Samba - temporary autogenerated HOST certificate"
#define LIFETIME          700*24*60*60
#define RSA_BITS          4096

/* 
   auto-generate a set of self signed certificates
*/
void tls_cert_generate(TALLOC_CTX *mem_ctx, 
                       const char *hostname, 
                       const char *keyfile, const char *certfile,
                       const char *cafile)
{
        gnutls_x509_crt cacrt, crt;
        gnutls_x509_privkey key, cakey;
        uint32_t serial = (uint32_t)time(NULL);
        unsigned char keyid[100];
        char buf[4096];
        size_t bufsize;
        size_t keyidsize = sizeof(keyid);
        time_t activation = time(NULL), expiry = activation + LIFETIME;
        int ret;

        if (file_exist(keyfile) || file_exist(certfile) || file_exist(cafile)) {
                DEBUG(0,("TLS autogeneration skipped - some TLS files already exist\n"));
                return;
        }

#define TLSCHECK(call) do { \
        ret = call; \
        if (ret < 0) { \
                DEBUG(0,("TLS %s - %s\n", #call, gnutls_strerror(ret))); \
                goto failed; \
        } \
} while (0)

        TLSCHECK(gnutls_global_init());

        DEBUG(0,("Attempting to autogenerate TLS self-signed keys for https for hostname '%s'\n", 
                 hostname));
        
#if defined(HAVE_GCRYPT_H) && !defined(HAVE_GNUTLS3)
        DEBUG(3,("Enabling QUICK mode in gcrypt\n"));
        gcry_control(GCRYCTL_ENABLE_QUICK_RANDOM, 0);
#endif

        DEBUG(3,("Generating private key\n"));
        TLSCHECK(gnutls_x509_privkey_init(&key));
        TLSCHECK(gnutls_x509_privkey_generate(key,   GNUTLS_PK_RSA, RSA_BITS, 0));

        DEBUG(3,("Generating CA private key\n"));
        TLSCHECK(gnutls_x509_privkey_init(&cakey));
        TLSCHECK(gnutls_x509_privkey_generate(cakey, GNUTLS_PK_RSA, RSA_BITS, 0));

        DEBUG(3,("Generating CA certificate\n"));
        TLSCHECK(gnutls_x509_crt_init(&cacrt));
        TLSCHECK(gnutls_x509_crt_set_dn_by_oid(cacrt, 
                                      GNUTLS_OID_X520_ORGANIZATION_NAME, 0,
                                      ORGANISATION_NAME, strlen(ORGANISATION_NAME)));
        TLSCHECK(gnutls_x509_crt_set_dn_by_oid(cacrt, 
                                      GNUTLS_OID_X520_ORGANIZATIONAL_UNIT_NAME, 0,
                                      CA_NAME, strlen(CA_NAME)));
        TLSCHECK(gnutls_x509_crt_set_dn_by_oid(cacrt,
                                      GNUTLS_OID_X520_COMMON_NAME, 0,
                                      hostname, strlen(hostname)));
        TLSCHECK(gnutls_x509_crt_set_key(cacrt, cakey));
        TLSCHECK(gnutls_x509_crt_set_serial(cacrt, &serial, sizeof(serial)));
        TLSCHECK(gnutls_x509_crt_set_activation_time(cacrt, activation));
        TLSCHECK(gnutls_x509_crt_set_expiration_time(cacrt, expiry));
        TLSCHECK(gnutls_x509_crt_set_ca_status(cacrt, 1));
        TLSCHECK(gnutls_x509_crt_set_key_usage(cacrt, GNUTLS_KEY_KEY_CERT_SIGN | GNUTLS_KEY_CRL_SIGN));
        TLSCHECK(gnutls_x509_crt_set_version(cacrt, 3));
        TLSCHECK(gnutls_x509_crt_get_key_id(cacrt, 0, keyid, &keyidsize));
#if HAVE_GNUTLS_X509_CRT_SET_SUBJECT_KEY_ID
        TLSCHECK(gnutls_x509_crt_set_subject_key_id(cacrt, keyid, keyidsize));
#endif
        TLSCHECK(gnutls_x509_crt_sign(cacrt, cacrt, cakey));

        DEBUG(3,("Generating TLS certificate\n"));
        TLSCHECK(gnutls_x509_crt_init(&crt));
        TLSCHECK(gnutls_x509_crt_set_dn_by_oid(crt, 
                                      GNUTLS_OID_X520_ORGANIZATION_NAME, 0,
                                      ORGANISATION_NAME, strlen(ORGANISATION_NAME)));
        TLSCHECK(gnutls_x509_crt_set_dn_by_oid(crt, 
                                      GNUTLS_OID_X520_ORGANIZATIONAL_UNIT_NAME, 0,
                                      UNIT_NAME, strlen(UNIT_NAME)));
        TLSCHECK(gnutls_x509_crt_set_dn_by_oid(crt,
                                      GNUTLS_OID_X520_COMMON_NAME, 0,
                                      hostname, strlen(hostname)));
        TLSCHECK(gnutls_x509_crt_set_key(crt, key));
        TLSCHECK(gnutls_x509_crt_set_serial(crt, &serial, sizeof(serial)));
        TLSCHECK(gnutls_x509_crt_set_activation_time(crt, activation));
        TLSCHECK(gnutls_x509_crt_set_expiration_time(crt, expiry));
        TLSCHECK(gnutls_x509_crt_set_ca_status(crt, 0));
#ifdef GNUTLS_KP_TLS_WWW_SERVER
        TLSCHECK(gnutls_x509_crt_set_key_purpose_oid(crt, GNUTLS_KP_TLS_WWW_SERVER, 0));
#endif
        TLSCHECK(gnutls_x509_crt_set_version(crt, 3));
        TLSCHECK(gnutls_x509_crt_get_key_id(crt, 0, keyid, &keyidsize));
#if HAVE_GNUTLS_X509_CRT_SET_SUBJECT_KEY_ID
        TLSCHECK(gnutls_x509_crt_set_subject_key_id(crt, keyid, keyidsize));
#endif
        TLSCHECK(gnutls_x509_crt_sign(crt, crt, key));
        TLSCHECK(gnutls_x509_crt_sign(crt, cacrt, cakey));

        DEBUG(3,("Exporting TLS keys\n"));

        bufsize = sizeof(buf);
        TLSCHECK(gnutls_x509_crt_export(crt, GNUTLS_X509_FMT_PEM, buf, &bufsize));
        if (!file_save(certfile, buf, bufsize)) {
                DEBUG(0,("Unable to save certificate in %s parent dir exists ?\n", certfile));
                goto failed;
        }

        bufsize = sizeof(buf);
        TLSCHECK(gnutls_x509_crt_export(cacrt, GNUTLS_X509_FMT_PEM, buf, &bufsize));
        if (!file_save(cafile, buf, bufsize)) {
                DEBUG(0,("Unable to save ca cert in %s parent dir exists ?\n", cafile));
                goto failed;
        }

        bufsize = sizeof(buf);
        TLSCHECK(gnutls_x509_privkey_export(key, GNUTLS_X509_FMT_PEM, buf, &bufsize));
        if (!file_save_mode(keyfile, buf, bufsize, 0600)) {
                DEBUG(0,("Unable to save privatekey in %s parent dir exists ?\n", keyfile));
                goto failed;
        }

        gnutls_x509_privkey_deinit(key);
        gnutls_x509_privkey_deinit(cakey);
        gnutls_x509_crt_deinit(cacrt);
        gnutls_x509_crt_deinit(crt);
        gnutls_global_deinit();

        DEBUG(0,("TLS self-signed keys generated OK\n"));
        return;

failed:
        DEBUG(0,("TLS certificate generation failed\n"));
}

#else
void tls_cert_dummy(void) {}
#endif