Load RSA private key generated by openssl to MacOS SecKeyRef fails - ios

I am working on a project that needs to read a RSA private key (DER format) into a MacOS's SecKeyRef object.
I generate the key by
openssl genrsa -out private.pem 1024
openssl rsa -in private.pem -outform DER -out private.der
I load the private.der to MacOS by using SecKeyCreateWithData:
unsigned char *keyBytes; // contains all the bytes from the file "private.der"
int keyBytesLen; // length of the data loaded
NSData keyData = [NSData dataWithBytes:keyBytes length:keyBytesLen];
NSDictionary* options = #{(id)kSecAttrKeyType: (id)kSecAttrKeyTypeRSA,
(id)kSecAttrKeyClass: (id)kSecAttrKeyClassPrivate,
(id)kSecAttrKeySizeInBits: #1024};
SecKeyRef privateKey = SecKeyCrecateWithData((__bridge CFDataRef) keyData, (__bridge CFDictionaryRef) options, &error);
OSstatus status = SecKeyDecrypt(privateKey, .... some encrypted message);
// status returns -50 (errSecParam)
So I notice the privateKey is loaded successfully, but it fails to decrypt the encrypted message. I am 100% sure other parameters I have put into SecKeyDecrypt() function is correct because it works if I generate the privateKey by macOS's built-in function rather than loading from a DER-format file generated by openssl.
I also notice that when I dump the key (binary format), the first few bytes (version header) is different from the key generated by MacOS's built-in function and openssl. If the key is generated by MacOS (ex: SecKeyGeneratePair) and outputed by SecKeyCopyExternalRepresentation, the first few bytes look like:
3082 025d 0201 0002 8181 ...
while the key generated by openssl looks like:
3082 025c 0201 0002 8181 ...
I know (based on PKCS#1) that these bytes represent the "version" of the private key but not sure how to interpret it.
Any help or similar working example to load key generated by openssl to MacOS's API will be appreciated

Related

DER Encoding Public Key created by cryptopp is different then openssl

I've been trying to create a DER encoded public key using an RSA private key. The way I normally create it is using the command line:
openssl rsa -pubout -outform DER -in ~/.keys/api_key.pem -out der_pub.der
When I use CryptoPP to create this file, they are slightly different. It seems it has an extra section. The one created by openssl has a little extra section. I'm assuming this is the BIT STRING mentioned in the CryptoPP API. https://www.cryptopp.com/docs/ref/class_r_s_a_function.html
void DEREncodePublicKey (BufferedTransformation &bt) const
encode subjectPublicKey part of subjectPublicKeyInfo, without the BIT STRING header
This is what my code looks like:
...
CryptoPP::RSA::PrivateKey rsaPrivate;
rsaPrivate.BERDecodePrivateKey(queue, false /*paramsPresent*/, queue.MaxRetrievable());
CryptoPP::ByteQueue bq;
rsaPrivate.DEREncodePublicKey(bq);
CryptoPP::FileSink fs1("cryptopp_pub.der", true);
bq.TransferTo(fs1);
CryptoPP::RSA::DEREncodePublicKey encodes subjectPublicKey part of subjectPublicKeyInfo, without the BIT STRING header
Try CryptoPP::RSA::PublicKey::DEREncode. Being careful to apply this to only the public key, as RSA::PrivateKey does overload the DEREncode method.
Here I'm using CryptoPP 8.2
Load DER encoded private key from disk
CryptoPP::RSA::PrivateKey private_key;
{
CryptoPP::FileSource file{"my.key", true};
private_key.BERDecodePrivateKey(file, false, -1);
}
Save out DER encoded public key
CryptoPP::FileSink sink{"my.pub", true};
CryptoPP::RSA::PublicKey{private_key}.DEREncode(sink);
OpenSSL:
# generate a new RSA private key (DER format)
openssl genrsa | openssl rsa -outform DER -out my.key
# hash/fingerprint the public key
openssl rsa -in my.key -inform DER -pubout -outform DER | openssl sha256
writing RSA key
362945ad4a5f87f27d3db3b4adbacaee0ebc3f778ee2fe76ef4fb09933148372
# compare against hash of our code sample's generated public key
cat my.pub | openssl sha256
362945ad4a5f87f27d3db3b4adbacaee0ebc3f778ee2fe76ef4fb09933148372
As another example; if we want CryptoPP to generate a SHA256 fingerprint:
std::string hash_out_str;
{
CryptoPP::SHA256 sha256;
CryptoPP::HashFilter filter{
sha256,
new CryptoPP::HexEncoder{
new CryptoPP::StringSink{hash_out_str}
}
};
CryptoPP::RSA::PublicKey{private_key}.DEREncode(filter); // intentionally slice to ensure we aren't exposing a public key
filter.MessageEnd();
}
std::cout << hash_out_str << '\n';
Outputs:
362945AD4A5F87F27D3DB3B4ADBACAEE0EBC3F778EE2FE76EF4FB09933148372
i.e., we need to copy/slice to a RSA::PublicKey to invoke the OpenSSL compatible DER encoding method

Apple Wallet NFC encryptionPublicKey

In Apple's documentation for the keys available for a Wallet pass, there's an option for a dictionary for NFC-related data. I understand that use of this key requires special permission from Apple. Regardless ...
message is straight forward -- it's the data passed to a NFC terminal (usually a unique identifier for the customer).
encryptionPublicKey, however, has me confused. Apple states it is the public encryption key used by the Value Added Services protocol. Use a Base64 encoded X.509 SubjectPublicKeyInfo structure containing a ECDH public key for group P256.
Can anyone explain what this second sentence means and/or what a developer would have to do to generate this? From what would one even generate the public/private keys?
You'll need the following to generate the public and private key. The private key is used by the merchant hardware when reading the pass and decoding the payload.
The compressed public key is what goes into your pass.json.
openssl ecparam -name prime256v1 -genkey -noout -out nfcKey.pem
openssl ec -in nfcKey.pem -pubout -out nfcPubkey.pem -conv_form compressed
cat nfcPubkey.pem
Outputs:
-----BEGIN PUBLIC KEY-----
MDkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDIgAC/Bu9nyAtG1DQe7t7jszLb+dZ1GbX
oR8G0rIXoak67NM=
-----END PUBLIC KEY---
You'll need Base64 key (without the newline) for the encryptionPublicKey field.
E.g.
MDkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDIgAC/Bu9nyAtG1DQe7t7jszLb+dZ1GbXoR8G0rIXoak67NM=

SWCrypt public key VS PKCS8PEM Key

I want to user SWCrypt for RSA encryption and decryption. i should send my public key base64 decoded to server. but when i try send generated public key base64 i can't get this error in server side:
let (privateKey, publicKey) = try CC.RSA.generateKeyPair(2048)
let publicKeyBase64 = publicKey.base64EncodedString()
error: java.security.InvalidKeyException: IOException: algid parse error, not a sequence
but when send PEMPublicKey getting successfully response.
let publicKeyPEM = SwKeyConvert.PublicKey.derToPKCS8PEM(publicKey)
what is difference between publicKeyBase64 and publicKeyPEM?
sample of generated key:
MIIBCgKCAQEAuWwCZpNXJtT2spBsDwrQaTFGVAjicM341Qzg+1whtlj9J60c/7HYe6AcGHa8Dinkiuk7Whs1Wpa34aa223WQsa+kFSNwkC6oDUXhewan3VEsv1uedzHc8JPlTXnItJsP8cIETFgHpdKWk462hU09mVCTtQTix0BEb8snS96wERvKq957OeaGtFasfT/bQfY0mbDu6eEMqswmfX8j84kuTfwWtqt6mLMTJaDwnsGc5WY1zkau68IQ/CBiiLpZ5hSVMs2pPj3Ao0+wNhR5MlMgdcwrU62SHWcMJ5cYssFgWZyZSvO3n/yW43fE5a1i+9Tm2trveGIdMR4d/MoA79/8IQIDAQAB
sample of generated PEM key :
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAuWwCZpNXJtT2spBsDwrQaTFGVAjicM341Qzg+1whtlj9J60c/7HYe6AcGHa8Dinkiuk7Whs1Wpa34aa223WQsa+kFSNwkC6oDUXhewan3VEsv1uedzHc8JPlTXnItJsP8cIETFgHpdKWk462hU09mVCTtQTix0BEb8snS96wERvKq957OeaGtFasfT/bQfY0mbDu6eEMqswmfX8j84kuTfwWtqt6mLMTJaDwnsGc5WY1zkau68IQ/CBiiLpZ5hSVMs2pPj3Ao0+wNhR5MlMgdcwrU62SHWcMJ5cYssFgWZyZSvO3n/yW43fE5a1i+9Tm2trveGIdMR4d/MoA79/8IQIDAQAB
how can send generated public key simple of PEM key format?
thanks.
X509 is a standard for Public Key Infraestructure, not a encoding format. You can encode a X509 public key in PEM (base64), DER(binary) or XML. Also the binary data of the public key can be represented in PCKS#1 or X509 SubjectPublicKeyInfo.
In my knowledge PKCS#8 is a standard for private keys. See PKCS #8: Private-Key Information Syntax Standard. So I guess SWCrypt is really using X509 SubjectPublicKeyInfo (Maybe i have not read some RFCs), which is what your server is waiting for.
let publicKeyPEM = SwKeyConvert.PublicKey.derToPKCS8PEM(publicKey)
SubjectPublicKeyInfo encapsulates the public key into a ASN.1 structure adding a header. If you encode the raw data of the public key (DER) using publicKey.base64EncodedString, that header is not added and your server does not know how to manage it.

How to use erlang public_key:decrypt_private?

I try to encrypt text with public RSA key and decrypt this text using a private RSA key. When I encrypt user public key it works.
encode public_key
encrypt_public_key(PlainText, PublicKey) ->
[ RSAEntry2 ] = public_key:pem_decode(PublicKey),
PubKey = public_key:pem_entry_decode( RSAEntry2 ),
public_key:encrypt_public(PlainText, PubKey).
But when I try to decrypt this text using a private key, it does not work, and I don't know why.
decode private key
decrypt_private_key(CryptText,PrivateKey) ->
[ RSAEntry2 ] = public_key:pem_decode(PrivateKey),
PrivKey = public_key:pem_entry_decode( RSAEntry2 ),
Result = public_key:decrypt_private(CryptText, PrivKey, rsa_pkcs1_padding ),
Result.
How i encode and try to decode
PublicKey = ems_util:open_file(?SSL_PATH ++ "/" ++ binary_to_list(<<"public_key.pem">>)),
CryptoText = ems_util:encrypt_public_key(ResponseData2,PublicKey),
PrivateKey = ems_util:open_file(?SSL_PATH ++ "/" ++ binary_to_list(<<"private_key.pem">>)),
%erro in this line
TextPlain = ems_util:decrypt_private_key(TextCrypt,PrivateKey).
Error
=ERROR REPORT==== 17-Mar-2017::10:59:29 ===
Ranch listener ems_http_server1, connection process <0.2159.0>, stream 1 had its request process <0.2160.0> exit with reason function_clause and stacktrace [{public_key,decrypt_private,[<<55,66,78,123,456,2456>>,<<55,173,2367,140,71>>,asn1_NOVALUE}],[{file,"public_key.erl"},{line,313}]},{ems_util,decrypt_private_key,2,[{file,"src/util/ems_util.erl"},{line,614}]},{ems_auth_user,do_barer_authorization,1,[{file,"src/auth/ems_auth_user.erl"},{line,51}]},{ems_dispatcher,lookup_request,1,[{file,"src/distpatcher/ems_dispatcher.erl"},{line,70}]},{ems_http_handler,init,2,[{file,"src/http/ems_http_handler.erl"},{line,22}]},{cowboy_handler,execute,2,[{file,"src/cowboy_handler.erl"},{line,39}]},{cowboy_stream_h,execute,3,[{file,"src/cowboy_stream_h.erl"},{line,172}]},{cowboy_stream_h,proc_lib_hack,3,[{file,"src/cowboy_stream_h.erl"},{line,157}]}]
I don't know what's happening.
I describle the solution for my problem. The problem is the public and the private keys are generated wrongly. The right way to generate a pair key rsa using openssl is:
openssl genrsa -out private.pem 2048
openssl rsa -in private.pem -out public.pem -outform PEM -pubout
These commands generate a correct key pair and the code now ir working correctly.

Reading Private Key in PEM format with LockBox

I have to digitally sign a string using the SHA-1 algorithm with RSA using PKCS#1 padding. I have downloaded Turbo Power Lockbox.
The private key I have is in PEM format and was created using openssl:
openssl req -x509 -nodes -days 365 -newkey rsa:1024 -sha1 -subj
"/C=US/ST=CA/L=Mountain View/CN=www.mycompany.com"
-keyout myrsakey.pem -out c:\temp\myrsacert.pem
Here is what it looks like:
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
If I am not mistaken, the component I want to use is TLbRSAKey. So I have tried to create key object and read it from file:
var
mPrivateKey: TLbRSAKey;
begin
mPrivateKey := TLbRSAKey.Create(aks1024);
mPrivateKey.LoadFromFile('C:\temp\myrsakey.pem');
On the LoadFromFile I get a "Invalid RSA Key" error. What am I doing wrong? Does Lockbox support keys in PEM format? None of the examples illustrate; everything seems to be in ASN format
I am not a delphi programmer, but I thought I'd try to provide some pointers.
First, make sure you generate a new private key for your real application. Now that you've shared your private key with us, we wouldn't want any open security holes out there.
Secondly, the ASN.1 format is generated using the DER output from OpenSSL. The PEM format is just the base-64 encoding of the binary ASN.1 structure (and the markers are added).
You can get back to DER in one of two ways:
1) You can parse and decode the base-64 data in the PEM envelope. To do this, just decode the data between the -----BEGIN/END RSA PRIVATE KEY----- markers.
Or, since you are creating a new key anyway... ;)
2) You could use the -outform DER argument when you generate your key using OpenSSL.
I'm not certain this will work for your application, but maybe it will help get you a little further.
TIP to convert a PEM provate key to DER format, use the rsa utility in OpenSSL:
openssl rsa -inform PEM -outform DER -in privkey.pem -out privkey.der

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