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Security-59306.11.20.tar.gz
[apple/security.git] / SecurityTool / sharedTool / scep.c
diff --git a/SecurityTool/sharedTool/scep.c b/SecurityTool/sharedTool/scep.c
new file mode 100644 (file)
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+/*
+ * Copyright (c) 2003-2004,2006-2007,2009-2010,2013-2014 Apple Inc. All Rights Reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ *
+ * scep.c
+ */
+
+#include <TargetConditionals.h>
+#if TARGET_OS_IPHONE && !TARGET_OS_SIMULATOR
+
+#include "SecurityCommands.h"
+
+#include <unistd.h>
+#include <uuid/uuid.h>
+#include <AssertMacros.h>
+
+#include <Security/SecItem.h>
+#include <Security/SecCertificateRequest.h>
+#include <Security/SecCertificatePriv.h>
+#include <Security/SecIdentityPriv.h>
+#include <Security/SecSCEP.h>
+#include <Security/SecCMS.h>
+
+#include <utilities/array_size.h>
+#include <utilities/SecIOFormat.h>
+
+#include <CommonCrypto/CommonDigest.h>
+
+#include <CFNetwork/CFNetwork.h>
+#include "SecBase64.h"
+#include <utilities/SecCFRelease.h>
+
+
+#include <fcntl.h>
+static inline void write_data(const char * path, CFDataRef data)
+{
+    int data_file = open(path, O_CREAT|O_WRONLY|O_TRUNC, 0644);
+    write(data_file, CFDataGetBytePtr(data), CFDataGetLength(data));
+    close(data_file);
+}
+
+#define BUFSIZE 1024
+
+static CF_RETURNS_RETAINED CFHTTPMessageRef load_request(CFHTTPMessageRef request, CFMutableDataRef data, int retry, bool validate_cert)
+{
+    CFHTTPMessageRef result = NULL;
+    
+    if (retry < 0)
+        return result;
+
+    CFReadStreamRef rs;
+    rs = CFReadStreamCreateForHTTPRequest(NULL, request);
+
+       if (!validate_cert) {
+               const void *keys[] = {
+                       kCFStreamSSLValidatesCertificateChain,
+               };
+               const void *values[] = {
+                       kCFBooleanFalse,
+               };
+               CFDictionaryRef dict = CFDictionaryCreate(NULL, keys, values,
+                       array_size(keys),
+                       &kCFTypeDictionaryKeyCallBacks,
+                       &kCFTypeDictionaryValueCallBacks);
+               CFReadStreamSetProperty(rs, kCFStreamPropertySSLSettings, dict);
+               CFRelease(dict);
+               CFReadStreamSetProperty(rs, kCFStreamPropertyHTTPAttemptPersistentConnection, kCFBooleanTrue);
+       }
+    
+    if (CFReadStreamOpen(rs)) {
+        do {
+            UInt8 buf[BUFSIZE];
+            CFIndex bytesRead = CFReadStreamRead(rs, buf, BUFSIZE);
+            if (bytesRead > 0) {
+                CFDataAppendBytes(data, buf, bytesRead);
+            } else if (bytesRead == 0) {
+                result = (CFHTTPMessageRef)CFReadStreamCopyProperty(rs, kCFStreamPropertyHTTPResponseHeader);
+                break;
+            } else {
+                CFStreamStatus status = CFReadStreamGetStatus(rs);
+                CFStreamError error = CFReadStreamGetError(rs);
+                fprintf(stderr, "CFReadStreamRead status=%ld error(domain=%" PRIdCFIndex " error=%ld)\n",
+                    status, error.domain, (long) error.error);
+                break;
+            }
+        } while (true);
+    } else {
+        CFStreamStatus status = CFReadStreamGetStatus(rs);
+        CFStreamError error = CFReadStreamGetError(rs);
+        fprintf(stderr, "CFReadStreamRead status=%ld error(domain=%" PRIdCFIndex " error=%ld)\n",
+            status, error.domain, (long) error.error);
+    }
+
+    CFReadStreamClose(rs);
+    CFRelease(rs);
+    return result;
+}
+
+static CF_RETURNS_RETAINED CFDataRef MCNetworkLoadRequest(CFURLRef url, CFDataRef content, CFStringRef type,
+    CFStringRef *contentType, bool validate_cert)
+{
+    CFMutableDataRef out_data = CFDataCreateMutable(kCFAllocatorDefault, 0);
+    CFHTTPMessageRef response = NULL;
+    CFStringRef request_type = content ? CFSTR("POST") : CFSTR("GET");
+    CFHTTPMessageRef request = CFHTTPMessageCreateRequest(kCFAllocatorDefault, 
+        request_type, url, kCFHTTPVersion1_0);
+    if (content)
+        CFHTTPMessageSetBody(request, content);
+    CFHTTPMessageSetHeaderFieldValue(request, CFSTR("Content-Type"), type);
+
+    int retries = 1;
+    do {
+        response = load_request(request, out_data, 1, validate_cert);
+        if (!response && retries) {
+            sleep(5);
+            CFDataSetLength(out_data, 0);
+        }
+    } while (!response && retries--);
+    
+    CFRelease(request);
+    
+    CFIndex status_code = response ? CFHTTPMessageGetResponseStatusCode(response) : 0;
+    if (!response || (200 != status_code)) {
+        CFStringRef url_string = CFURLGetString(url);
+        if (url_string && request_type && out_data)
+            fprintf(stderr, "MCNetworkLoadRequest failed to load\n");
+
+        CFReleaseNull(out_data);
+        goto out;
+    }
+
+    if (contentType)
+        *contentType = CFHTTPMessageCopyHeaderFieldValue(response, CFSTR("Content-Type"));
+out:
+    CFReleaseSafe(response);
+    return out_data;
+}
+
+static void _query_string_apply(CFMutableStringRef query_string, const void *key, const void *value)
+{
+    CFStringRef escaped_key = 
+        CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, 
+            (CFStringRef)key, NULL, CFSTR("+/="), kCFStringEncodingUTF8);
+    CFStringRef escaped_value = 
+        CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, 
+            (CFStringRef)value, NULL, CFSTR("+/="), kCFStringEncodingUTF8);
+    
+    if (CFStringGetLength(query_string) > 1)
+        CFStringAppend(query_string, CFSTR("&"));
+
+    CFStringAppendFormat(query_string, NULL, CFSTR("%@=%@"), escaped_key, escaped_value);
+    CFRelease(escaped_key);
+    CFRelease(escaped_value);
+}
+
+static CF_RETURNS_RETAINED CFURLRef scep_url_operation(CFStringRef base, CFStringRef operation, CFStringRef message)
+{
+    CFURLRef url = NULL, base_url = NULL;
+    CFMutableStringRef query_string = 
+        CFStringCreateMutableCopy(kCFAllocatorDefault, 0, CFSTR("?"));
+    require(query_string, out);
+    require(operation, out);
+    _query_string_apply(query_string, CFSTR("operation"), operation);
+    if (message)
+        _query_string_apply(query_string, CFSTR("message"), message);
+    base_url = CFURLCreateWithString(kCFAllocatorDefault, base, NULL);
+    url = CFURLCreateWithString(kCFAllocatorDefault, query_string, base_url);
+out:
+    if (query_string)
+        CFRelease(query_string);
+    if (base_url)
+        CFRelease(base_url);
+    return url;
+}
+
+static CF_RETURNS_RETAINED CFDataRef perform_pki_op(CFStringRef scep_base_url, CFDataRef scep_request, bool scep_can_use_post, bool validate_cert)
+{
+       CFDataRef scep_reply = NULL;
+       CFURLRef pki_op = NULL;
+    if (scep_can_use_post) {
+        pki_op = scep_url_operation(scep_base_url, CFSTR("PKIOperation"), NULL);
+        scep_reply = MCNetworkLoadRequest(pki_op, scep_request, CFSTR("application/x-pki-message"), NULL, validate_cert);
+    } else {
+        SecBase64Result base64_result;
+        size_t buffer_length = CFDataGetLength(scep_request)*2+1;
+        char *buffer = malloc(buffer_length);
+        require(buffer, out);
+        size_t output_size = SecBase64Encode2(CFDataGetBytePtr(scep_request), CFDataGetLength(scep_request), buffer, buffer_length,
+            kSecB64_F_LINE_LEN_INFINITE, -1, &base64_result);
+        *(buffer + output_size) = '\0';
+        require(!base64_result, out);
+        CFStringRef message = CFStringCreateWithCString(kCFAllocatorDefault, buffer, kCFStringEncodingASCII);
+        require(message, out);
+               pki_op = scep_url_operation(scep_base_url, CFSTR("PKIOperation"), message);
+        CFRelease(message);
+        fprintf(stderr, "Performing PKIOperation using GET\n");
+        scep_reply = MCNetworkLoadRequest(pki_op, NULL, CFSTR("application/x-pki-message"), NULL, validate_cert);
+    }
+out:
+       CFReleaseSafe(pki_op);
+       return scep_reply;
+}
+
+
+static inline CF_RETURNS_RETAINED CFStringRef uuid_cfstring()
+{
+    char uuid_string[40] = "CN=";
+    uuid_t uuid;
+    uuid_generate_random(uuid);
+    uuid_unparse(uuid, uuid_string+3);
+    return CFStringCreateWithCString(kCFAllocatorDefault, uuid_string, kCFStringEncodingASCII);
+}
+
+/* /O=foo/CN=blah => [ [ [ O, foo ] ], [ [ CN, blah ] ] ] */
+static void make_subject_pairs(const void *value, void *context)
+{
+    CFArrayRef entries = NULL, array = NULL;
+    if (!CFStringGetLength(value))
+        return; /* skip '/'s that aren't separating key/vals */
+    entries = CFStringCreateArrayBySeparatingStrings(kCFAllocatorDefault, value, CFSTR("="));
+    require(entries, out);
+    if (CFArrayGetCount(entries)) {
+        array = CFArrayCreate(kCFAllocatorDefault, (const void **)&entries, 1, &kCFTypeArrayCallBacks);
+        require(array, out);
+        CFArrayAppendValue((CFMutableArrayRef)context, array);
+    }
+out:
+    if (entries) CFRelease(entries);
+    if (array) CFRelease(array);
+}
+
+static CFArrayRef make_scep_subject(CFStringRef scep_subject_name)
+{
+    CFMutableArrayRef subject = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
+    require(subject, out);
+    CFArrayRef entries = NULL;
+    entries = CFStringCreateArrayBySeparatingStrings(kCFAllocatorDefault, scep_subject_name, CFSTR("/"));
+    require(entries, out);
+    CFArrayApplyFunction(entries, CFRangeMake(0, CFArrayGetCount(entries)), make_subject_pairs, subject);
+    CFRelease(entries);
+    if (CFArrayGetCount(subject))
+        return subject;
+out:
+    if (subject) CFRelease(subject);
+    return NULL;
+}
+
+
+extern int command_scep(int argc, char * const *argv)
+{
+    int             result = 1, verbose = 0;
+    char            ch;
+    int key_usage = 1, key_bitsize = 1024;
+    bool validate_cert = true;
+    CFStringRef scep_challenge = NULL, scep_instance_name = NULL,
+        scep_subject_name = uuid_cfstring(), scep_subject_alt_name = NULL,
+        scep_capabilities = NULL;
+
+    SecCertificateRef ca_certificate = NULL, ra_certificate = NULL;
+    CFArrayRef cert_array = NULL;
+    CFDataRef caps_data = NULL;
+
+    while ((ch = getopt(argc, argv, "vu:b:c:n:s:h:xo:")) != -1)
+    {
+        switch (ch)
+        {
+        case 'v':
+            verbose++;
+            break;
+        case 'u':
+            key_usage = atoi(optarg);
+            break;
+        case 'b':
+            key_bitsize = atoi(optarg);
+            break;
+        case 'c':
+            CFReleaseNull(scep_challenge);
+            scep_challenge = CFStringCreateWithCString(kCFAllocatorDefault, optarg, kCFStringEncodingUTF8);
+            break;
+        case 'n':
+            CFReleaseNull(scep_instance_name);
+            scep_instance_name = CFStringCreateWithCString(kCFAllocatorDefault, optarg, kCFStringEncodingUTF8);
+            break;
+        case 's':
+            CFReleaseNull(scep_subject_name);
+            scep_subject_name = CFStringCreateWithCString(kCFAllocatorDefault, optarg, kCFStringEncodingUTF8);
+            break;
+        case 'h':
+            CFReleaseNull(scep_subject_alt_name);
+            scep_subject_alt_name = CFStringCreateWithCString(kCFAllocatorDefault, optarg, kCFStringEncodingUTF8);
+            break;
+       case 'x':
+           validate_cert = false;
+           break;
+        case 'o':
+            CFReleaseNull(scep_capabilities);
+            scep_capabilities = CFStringCreateWithCString(kCFAllocatorDefault, optarg, kCFStringEncodingUTF8);
+            break;
+        default:
+            CFReleaseNull(scep_subject_name);
+            CFReleaseNull(scep_capabilities);
+            CFReleaseNull(scep_challenge);
+            CFReleaseNull(scep_instance_name);
+            CFReleaseNull(scep_subject_alt_name);
+            return SHOW_USAGE_MESSAGE;
+        }
+    }
+
+    argc -= optind;
+    argv += optind;
+
+    if (argc != 1) {
+        CFReleaseNull(scep_subject_name);
+        CFReleaseNull(scep_capabilities);
+        CFReleaseNull(scep_challenge);
+        CFReleaseNull(scep_instance_name);
+        CFReleaseNull(scep_subject_alt_name);
+        return SHOW_USAGE_MESSAGE;
+    }
+
+    CFDataRef scep_request = NULL;
+    CFArrayRef issued_certs = NULL;
+    SecCertificateRef leaf = NULL;
+    SecIdentityRef candidate_identity = NULL;
+    CFMutableDictionaryRef csr_parameters = NULL;
+    CFDataRef scep_reply = NULL;
+    SecKeyRef phone_publicKey = NULL, phone_privateKey = NULL;
+    CFStringRef scep_base_url = NULL;
+    CFDictionaryRef identity_add = NULL;
+
+    CFNumberRef scep_key_usage = NULL;
+    CFNumberRef scep_key_bitsize = NULL;
+
+    CFURLRef url = NULL;
+
+    CFDataRef data = NULL;
+    CFStringRef ctype = NULL;
+
+    scep_base_url = CFStringCreateWithCString(kCFAllocatorDefault, argv[0], kCFStringEncodingASCII);
+
+#if 0
+    CFStringRef uuid_cfstr = uuid_cfstring();
+    require(uuid_cfstr, out);
+    const void * ca_cn[] = { kSecOidCommonName, uuid_cfstr };
+    CFArrayRef ca_cn_dn = CFArrayCreate(kCFAllocatorDefault, ca_cn, 2, NULL);
+    const void *ca_dn_array[1];
+    ca_dn_array[0] = CFArrayCreate(kCFAllocatorDefault, (const void **)&ca_cn_dn, 1, NULL);
+    CFArrayRef scep_subject = CFArrayCreate(kCFAllocatorDefault, ca_dn_array, array_size(ca_dn_array), NULL);
+#else
+    CFArrayRef scep_subject = make_scep_subject(scep_subject_name);
+    require(scep_subject, out);
+    CFShow(scep_subject);
+#endif
+
+    scep_key_usage = CFNumberCreate(kCFAllocatorDefault, kCFNumberIntType, &key_usage);
+    scep_key_bitsize = CFNumberCreate(kCFAllocatorDefault, kCFNumberIntType, &key_bitsize);
+
+    const void *keygen_keys[] = { kSecAttrKeyType, kSecAttrKeySizeInBits };
+    const void *keygen_vals[] = { kSecAttrKeyTypeRSA, scep_key_bitsize };
+    CFDictionaryRef keygen_parameters = CFDictionaryCreate(kCFAllocatorDefault, 
+        keygen_keys, keygen_vals, array_size(keygen_vals),
+        &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks );
+    CFRelease(scep_key_bitsize);
+    require_noerr(SecKeyGeneratePair(keygen_parameters, &phone_publicKey, &phone_privateKey), out);
+    CFRelease(keygen_parameters);
+
+    /* GetCACert
+    
+        A binary X.509 CA certificate is sent back as a MIME object with a
+        Content-Type of application/x-x509-ca-cert.
+        
+        When an RA exists, both CA and RA certificates must be sent back in
+        the response to the GetCACert request.  The RA certificate(s) must be
+        signed by the CA.  A certificates-only PKCS#7 [RFC2315] SignedData is
+        used to carry the certificates to the requester, with a Content-Type
+        of application/x-x509-ca-ra-cert.
+    */
+    SecCertificateRef ra_encryption_certificate = NULL;
+    CFArrayRef ra_certificates = NULL;
+    CFTypeRef scep_certificates = NULL;
+    SecCertificateRef scep_signing_certificate = NULL;
+
+    url = scep_url_operation(scep_base_url, CFSTR("GetCACert"), scep_instance_name);
+    data = MCNetworkLoadRequest(url, NULL, NULL, &ctype, validate_cert);
+
+    if (data && ctype) {
+        if (CFEqual(CFSTR("application/x-x509-ca-cert"), ctype)) {
+            ca_certificate = SecCertificateCreateWithData(kCFAllocatorDefault, (CFDataRef)data);
+            fprintf(stderr, "GetCACert returned a single CA certificate.\n");
+        } else if (CFEqual(ctype, CFSTR("application/x-x509-ca-ra-cert"))) {
+            cert_array = SecCMSCertificatesOnlyMessageCopyCertificates(data);
+            
+            require_noerr(SecSCEPValidateCACertMessage(cert_array,
+                NULL,
+                &ca_certificate,
+                &ra_certificate,
+                &ra_encryption_certificate), out);
+
+            if (ra_certificate && ra_encryption_certificate) {
+                const void *ra_certs[] = { ra_encryption_certificate, ra_certificate };
+                ra_certificates = CFArrayCreate(kCFAllocatorDefault, ra_certs, array_size(ra_certs), &kCFTypeArrayCallBacks);
+                fprintf(stderr, "GetCACert returned a separate signing and encryption certificates for RA.\n");
+            }
+        }
+    }
+
+    fprintf(stderr, "CA certificate to issue cert:\n");
+    CFShow(ca_certificate);
+    
+    if (ra_certificates) {
+        scep_certificates = ra_certificates;
+        scep_signing_certificate = ra_certificate;
+    } else if (ra_certificate) {
+        scep_certificates = ra_certificate;
+        scep_signing_certificate = ra_certificate;
+    } else if (ca_certificate) { 
+        scep_certificates = ca_certificate;
+        scep_signing_certificate = ca_certificate;
+    } else {
+        fprintf(stderr, "Unsupported GetCACert configuration: please file a bug.\n");
+        goto out;
+    }
+
+    (void) scep_signing_certificate; // Silence analyzer
+
+#if 0
+        GetCACaps capabilities advertised by SCEP server:
+
+   +--------------------+----------------------------------------------+
+   | Keyword            | Description                                  |
+   +--------------------+----------------------------------------------+
+   | "GetNextCACert"    | CA Supports the GetNextCACert message.       |
+   | "POSTPKIOperation" | PKIOPeration messages may be sent via HTTP   |
+   |                    | POST.                                        |
+   | "Renewal"          | Clients may use current certificate and key  |
+   |                    | to authenticate an enrollment request for a  |
+   |                    | new certificate.                             |
+   | "SHA-512"          | CA Supports the SHA-512 hashing algorithm in |
+   |                    | signatures and fingerprints.                 |
+   | "SHA-256"          | CA Supports the SHA-256 hashing algorithm in |
+   |                    | signatures and fingerprints.                 |
+   | "SHA-1"            | CA Supports the SHA-1 hashing algorithm in   |
+   |                    | signatures and fingerprints.                 |
+   | "DES3"             | CA Supports triple-DES for encryption.       |
+   +--------------------+----------------------------------------------+
+#endif
+
+    bool scep_can_use_post = false;
+    bool scep_use_3des = false;
+    bool scep_can_use_sha1 = false;
+    bool scep_can_use_sha512 = false;
+    bool scep_can_use_sha256 = false;
+
+    CFArrayRef caps = NULL;
+    if (!scep_capabilities) {
+        CFURLRef ca_caps_url = scep_url_operation(scep_base_url, CFSTR("GetCACaps"), scep_instance_name);
+        require(ca_caps_url, out);
+        caps_data = MCNetworkLoadRequest(ca_caps_url, NULL, NULL, NULL, validate_cert);
+        CFRelease(ca_caps_url);
+        if (caps_data) {
+            CFStringRef caps_data_string = CFStringCreateFromExternalRepresentation(kCFAllocatorDefault, caps_data, kCFStringEncodingASCII);
+            require(caps_data_string, out);
+            caps = CFStringCreateArrayBySeparatingStrings(kCFAllocatorDefault, caps_data_string, CFSTR("\n"));
+            if (!caps) {
+                fprintf(stderr, "GetCACaps couldn't be parsed:\n");
+                CFShow(caps_data);
+            }
+            CFRelease(caps_data);
+            CFRelease(caps_data_string);
+        }
+    } else {
+        caps = CFStringCreateArrayBySeparatingStrings(kCFAllocatorDefault, scep_capabilities, CFSTR(","));
+    }
+
+    if (caps) {
+        fprintf(stderr, "GetCACaps advertised following capabilities:\n");
+        CFShow(caps);
+
+        CFRange caps_length = CFRangeMake(0, CFArrayGetCount(caps));
+        scep_can_use_post = CFArrayContainsValue(caps, caps_length, CFSTR("POSTPKIOperation"));
+        scep_use_3des = CFArrayContainsValue(caps, caps_length, CFSTR("DES3"));
+        scep_can_use_sha1 = CFArrayContainsValue(caps, caps_length, CFSTR("SHA-1"));
+        scep_can_use_sha256 = CFArrayContainsValue(caps, caps_length, CFSTR("SHA-256"));
+        scep_can_use_sha512 = CFArrayContainsValue(caps, caps_length, CFSTR("SHA-512"));
+
+        // We probably inteded these to be the values and not override them below..
+        // but for now to quiet the analyzer we reference them here. see <rdar://problem/15010402> scep.c, command_scep assumes 3des and sha1
+        (void) scep_use_3des;
+        (void) scep_can_use_sha1;
+        CFRelease(caps);
+    }
+
+    scep_use_3des = true;
+    scep_can_use_sha1 = true;
+
+    csr_parameters = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, 
+        &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
+    if (scep_key_usage)
+        CFDictionarySetValue(csr_parameters, kSecCertificateKeyUsage, scep_key_usage);
+    if (scep_challenge)
+        CFDictionarySetValue(csr_parameters, kSecCSRChallengePassword, scep_challenge);
+    else
+        fprintf(stderr, "No SCEP challenge provided, hope that's ok.\n");
+
+    if (!scep_use_3des) {
+        CFDictionarySetValue(csr_parameters, kSecCMSBulkEncryptionAlgorithm, kSecCMSEncryptionAlgorithmDESCBC);
+        fprintf(stderr, "SCEP server does not support 3DES, falling back to DES.  You should reconfigure your server.\n");
+    }
+
+    if (scep_can_use_sha512) {
+        CFDictionarySetValue(csr_parameters, kSecCMSSignHashAlgorithm, kSecCMSHashingAlgorithmSHA512);
+    } else if (scep_can_use_sha256) {
+        CFDictionarySetValue(csr_parameters, kSecCMSSignHashAlgorithm, kSecCMSHashingAlgorithmSHA256);
+    } else if (scep_can_use_sha1) {
+        CFDictionarySetValue(csr_parameters, kSecCMSSignHashAlgorithm, kSecCMSHashingAlgorithmSHA1);
+    } else {
+        fprintf(stderr, "SCEP server does not support SHA-1.  You must reconfigure your server.\n");
+    }
+
+    if (scep_subject_alt_name) {
+        fprintf(stderr, "Adding subjectAltName to request\n");
+        CFDictionaryRef subject_alt_name = CFDictionaryCreate(kCFAllocatorDefault,
+            (const void **)&kSecSubjectAltNameDNSName, (const void **)&scep_subject_alt_name,
+            1, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
+        CFDictionarySetValue(csr_parameters, kSecSubjectAltName, subject_alt_name);
+    }
+
+    SecIdentityRef self_signed_identity = SecSCEPCreateTemporaryIdentity(phone_publicKey, phone_privateKey);
+
+    // store encryption identity in the keychain because the decrypt function looks in there only
+    identity_add = CFDictionaryCreate(NULL,
+        (const void **)&kSecValueRef, (const void **)&self_signed_identity, 1, NULL, NULL);
+       require_noerr(SecItemAdd(identity_add, NULL), out);
+
+    require(scep_request = SecSCEPGenerateCertificateRequest((CFArrayRef)scep_subject, 
+        csr_parameters, phone_publicKey, phone_privateKey, self_signed_identity,
+        scep_certificates), out);
+
+    fprintf(stderr, "storing scep_request.der\n");
+    write_data("scep_request.der", scep_request);
+
+       scep_reply = perform_pki_op(scep_base_url, scep_request, scep_can_use_post, validate_cert);
+    require(scep_reply, out);
+
+    require_action(CFDataGetLength(scep_reply), out, fprintf(stderr, "Empty scep_reply, exiting.\n"));
+    fprintf(stderr, "Storing scep_reply.der\n");
+    write_data("scep_reply.der", scep_reply);
+
+       CFErrorRef server_error = NULL;
+       int retry_count = 3;
+    while ( !(issued_certs = SecSCEPVerifyReply(scep_request, scep_reply, scep_certificates, &server_error)) &&
+                       server_error &&
+                       retry_count--)
+       {
+               CFDataRef retry_get_cert_initial = NULL;
+               CFDictionaryRef error_dict = CFErrorCopyUserInfo(server_error);
+               retry_get_cert_initial = SecSCEPGetCertInitial(ra_certificate ? ra_certificate : ca_certificate, scep_subject, NULL, error_dict, self_signed_identity, scep_certificates);
+               CFReleaseNull(scep_reply);
+        CFReleaseSafe(error_dict);
+               fprintf(stderr, "Waiting 10 seconds before trying a GetCertInitial\n");
+               sleep(10);
+               scep_reply = perform_pki_op(scep_base_url, retry_get_cert_initial, scep_can_use_post, validate_cert);
+        CFReleaseSafe(retry_get_cert_initial);
+       }
+
+    require(issued_certs, out);
+       require_string(CFArrayGetCount(issued_certs) > 0, out, "No certificates issued.");
+    
+    leaf = (SecCertificateRef)CFArrayGetValueAtIndex(issued_certs, 0);
+    require(leaf, out);
+    CFDataRef leaf_data = SecCertificateCopyData(leaf);
+    if (leaf_data) {
+        fprintf(stderr, "Storing issued_cert.der\n");
+        write_data("issued_cert.der", leaf_data);
+        CFRelease(leaf_data);
+    }
+    CFShow(leaf);
+
+    candidate_identity = SecIdentityCreate(kCFAllocatorDefault, leaf, phone_privateKey);
+
+    const void *keys_ref_to_persist[] = { 
+        /*kSecReturnPersistentRef, */kSecValueRef, kSecAttrLabel };
+    const void *values_ref_to_persist[] = { 
+        /*kCFBooleanTrue, */candidate_identity, scep_subject_name };
+    CFDictionaryRef dict = CFDictionaryCreate(NULL, 
+            (const void **)keys_ref_to_persist, 
+            (const void **)values_ref_to_persist, 
+            array_size(keys_ref_to_persist),
+            &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
+    OSStatus status = SecItemAdd(dict, NULL);
+    require_noerr_action(status, out, fprintf(stderr, "failed to store new identity, SecItemAdd: %" PRIdOSStatus, status));
+    result = 0;
+    
+out:
+    if (identity_add)
+        SecItemDelete(identity_add);
+    CFReleaseSafe(identity_add);
+    //if (uuid_cfstr) CFRelease(uuid_cfstr);
+    CFReleaseSafe(candidate_identity);
+    CFReleaseSafe(scep_request);
+    CFReleaseSafe(scep_reply);
+    CFReleaseSafe(scep_key_usage);
+    CFReleaseSafe(scep_key_bitsize);
+    CFReleaseSafe(csr_parameters);
+    CFReleaseSafe(scep_subject_name);
+    CFReleaseSafe(scep_base_url);
+    CFReleaseSafe(url);
+    CFReleaseSafe(issued_certs);
+    CFReleaseSafe(data);
+    CFReleaseSafe(ctype);
+    CFReleaseNull(ca_certificate);
+    CFReleaseNull(scep_capabilities);
+    CFReleaseNull(scep_challenge);
+    CFReleaseNull(scep_instance_name);
+    CFReleaseNull(scep_subject_alt_name);
+    CFReleaseNull(cert_array);
+    CFReleaseNull(caps_data);
+    
+    return result;
+}
+
+
+#endif // TARGET_OS_MAC