I have a string encrypted in PHP using following code
function encrypt($string, $publicKey)
{
openssl_public_encrypt($string, $cryptedText, $publicKey);
return base64_encode($cryptedText);
}
$publicKey = file_get_contents('public.crt');
$encryptedText = encrypt('Test', $publicKey);
This works fine in PHP, i am able to encrypt/decrypt using public/private key pair.
The encryptedText is sent to iOS application where i want to decrypt the same string, i tried with multiple approaches and nothing seems to be working, any pointer to do the following is appreciated.
Decrypt OpenSSL encrypted string received from PHP in Objective-C
Encrypt and send data to PHP for Decrypting (should support openssl_private_decrypt)
I used this library for iOS which worked perfectly.
https://github.com/jslim89/RSA-Example
Related
I have no expertise with cryptography, i'm trying to decrypt a JWE payload in ASP.net core C#, the information that i have is the encryption was performed with RSA-OAEP-256 and A256GCM, so i'm using Jose libraries do deal with cryptography, the code is like:
eyJhbGciOiJSU0EtT0FFUC0yNTYiLCJlbmMiOiJBMjU2R0NNIn0.rb3as5DV3PjfYM9cmxO1uE_OaLBt_gFMG9oe1iW_8999KNXEcxAuENaAJgD0fIWdrYD0UwDfkPxzG2cKy3SkvhQE5af7HNDuJBK7p_jjWZMNxtLO3IWCVbcYmH8r-TJEf4MPrDQi_0wP0QLIqH9aR3EVzRdkZ0tn1f8uSsaRlv7rXX_09mPME8V3y7dIDVAKJ0upvJvuyjnsNuAxXVAKvXjNdesKE_GMc3P5ZH6tOBb78a3uLyTOVf-itdR0f2Y7932QPnWbOM1d45mYARUK8Q28IHlKnyhntkA9YP8HQfvFdyMnAKhzPiybSU3Hg1U6wOh6qeYOqN4IIUedzZz__HFZZLpfPJHUacEXfgOWlPO3ZryMxN9v13pDG223oHl-9zbCOdtNsU3igOWlDM4094MECfpYWWem9cuEnbADjsyqVaq0l3CoL8MLUvDKpEjgI7ezopX0UFOlTWXjDxK-EmWeHOJlUAOjRJKUtmJBhiqtjY4quWsTO5xRzX-_fPyFw2Cql2T2_03FDNgZY6u8GpvmBR3f9E1jXqzNI36vbIdtBa6l0tksOPBnLeG070boMdViKMdUxAjzCW1EcUvaXo_vgOZ-ZU8_loOvGBOYmzE6myesQCMDaHXrSJROoR-G5lk5OO-hED6KWUptkqKI5vAuAHGuojq0_1d2YT4X4e8._jpZ8zc1XWIEFVmu.TKbdl02R_2q6-QwtW4cnUiNDoXhFX_fkTDxrhxofM8BhLTMhMk1cx3jvSPJADftBd5NgHghOouZePw_NwapFpNUwgFq__QvPVKcw6QQwU1IKcuh-ShfSJRtr9oVC93zQprZSvgLJsf5K-46sbjnEBc6dzCsL07r3M9fbg4XwaJyRW7iriLTXFbFEd-CbsqlGgZupHGUbn0W_h5PVYTuwAp4I7wyp_k2xF0i9MQRcLk04fm--zdwYo7-FfM3yfsz129OXzpH7tp6c_dl-5D53_cleLFLAIn1BNnDwVFfKIPkjbjz8_NzGoXWWESW8DP00Z2Of4qVgdhtBWunduriM7NyDWaiDWgePt3qX0A3nvSp6bIp9sXdZYiuGVM3z7-iMb-oJPsj1Abx5MuRHpbvovNLHY89QnV8Qf43TCUOGxpgiNcULd4QxeLn2NmXcmbxlFVxhGHxq44XHF0A14dEiWSYp4001T7lun-yv3DPZuiGiO-L4iKHZT-gnHAzjaDIyXVo5JsL1qWGVi59DJneQrnyjodZs7ESCUIbOASJ5SJ9QtSOu-uyvKVdyK6Tfw9-cGNXAzDBAOBmHcnxMOtWcZ6AscDJhpI_2quoktpTD9GkEM0gItKZ5W3r99i8t_RoZCakBdBY6D5gwVg4yFsJyb1YvqsYsH1X8MQBPdrVBTc4DUT0M0ucpfl5bV3nlMxxEffCyk-jbNNXid9_kOjq4Xv3-pHO4qJUQpJvRYIvGqyC0Ep1swo3-gbsUIjtEfyLlf2JkcDIM5WkV_iSvEbjch9lceTMKzjQVZgMnDWPvTtEvAZCXUxbRu9wE9fuX9F2W-yJ_DyB0o871IOhdDi0VyQcipQ2wkvuZecu9uqLFGtVk5NaPxYq0uOyaDQ3QzDwucAMwalaXPua9qjhLjM6TCePgn_ncVdN5jckMXo--RRAX3o4G1Hm8_xcJ6Amcvl8vsb7hUTdXY6um6CT-WDHbi-FQgMyyn-vlC64NJdngvT3uWvcKETS8UoKhp78nFDy20qWXIqSzxwi7rf60OL7vPZ_6McVfXORTbMjxvGRTT5skgkY58B5VPvB1c6vN12tKN3E3lqbJCpzass0rSzbfBxdRDg-PIV-Nuv0S-ch9aUxA5h6cMrYBZMQuiV-RO3EoqfQSU0JNGJuGir8mQAKuI5pJwROKrn1cCAaTSrcueobXz_ppJgZdxzjh_dUzZhfUrrE7DqJgPqHbuEPju7ViB39iPLsiniDz3W1iOhQKSbFDNzLmG_yzjKv1jF90onqIyo_mLN3kVlxHyvgP4MA8405OJCR_Cqmob0djhkiRsJCfNWUuVmmq0q0YPTfFIAn_R9A9Zdlwd8Ybg88_RKegLMwySgvfWT27w2OwGMQX6kCrPxV5pWS57lgmPiflq-R1H1uHXvBDoXySx3Uzv1J2ElzvtQGVufZFBznnirsQI87cwxSz76gWiVelf4GNJzRme3O1XRPhmlMlTBWCHOASRxTo9mM964oHc5g3cIRWrzNFppTV_FkJQ6cwPFYYjFdSA3Hh1w8_RxCxyXncsunAZoniCgV6KEBN7A5KybKMu424JQqWqdlKQqHBW7XLdqMnMH-ryzie22fGmIn4RrT5ha6ZI43rvLREt_4dYJJpmh4yw1f7Bh-8mIuKd1ha3lERWP0qZhSR6sSsCHob_UTe4JW_KwVT0om4FAgMzbLoKoZf1v01QHHn0ISSH9cvtgwv8TObcleMkEYrDJ_MxsSxOKm-B7VoKFDEhtns0ybZA_QYEK40voAzhrGO4CPjsOR7tWKIUFk3veNJRxmixBeGVP7Up7KAvXk7wAhRg060MzZ0Gf4kaWi6IS-H_hWSPYbb0NO0IQRcGYFXALt58p0hO61HpUqG5gnQGiceiMnj1DVKIVAbtnUhB_rGcrePPCKT_TQIeCyO4FRjtHw73iYePZgacVEJDGOqthPlVWJpKF9IWeUu5Ngqc3j6L75bQ4uuvUGVHAORbH3bzXoxxqx4hjU2kI0KvQwGs0VC6rCCgC2GCqJmn3-W0jxir9Mw3VBMaBOOpslv-FSMLriL4UX1solBR3pZ7bCm1vGCUooaj9tG0Pp4n6dwqGz54hkJ5vgYX5xEKZMYYJxhhKomRFNzvhJtli9qe4lNLUsMHEnwcs-BX1tMi7JSOxmPm5BNT_A7qYeRj4dJh4cR926geYdQpcXHhYC9qyNXuqsLG5Qf88rPqMeQerwBmxcwGbTUh2eUpSu4dZZzWuCUiG92Fb55UBtElxZ0mDsQ6SPso6g44oaBNaBbOJ1DnigSE6n1X-yz2HyRjYKHLCpbSHz2xDpQaHSUMVuHphOlS69Wn0Mwb_HljnQU0S34HJya1-zivBIDepkmt3_9EhLy3La872n3H1IEzkaNX7cjCr77imU2lQ32G1iwbFAo4FvJfkJhYwP2xLh1Q38GeE_2vsiQlu1iFr3Fs_Wxv-hYW6rnAz1B_1MSOI0slWMQywIhqZ7dbyyWv_S-oxecVneZ4LlSW-hxCYJGtrsGJtnEaRHVYZJ-N-MjwBm9nJU4P8mY9Nz9MPbWbovb8gJ5DLXFppZjReRk2A2zHTGKzav6Q0DYKI0NGmSDHJW6UbSjVzBBJe2r85NS4u5HGS_wyEhXXnMtJZdn6VBQj9AEY4Jrt2xZzCRoqWlUI46uMObvWq5qvkKCPcSLKyrHEIigbR3JmW3zzDNvc39RmiC6cbJ0Ypb-G0D4CNwdV2bemLzs29NIWms75cqMHxlkyKOqEX5UsYlGBhra_kM.vykYzq6TQ8ApQdyREGo6-g
var jwtSettings = new JwtSettings();
jwtSettings.RegisterMapper(new JwtPayloadConverter.JsonMapperJwt());
var decodedJwt = Jose.JWT.Decode(paylaodRetornoStone2, rsa, Jose.JweAlgorithm.RSA_OAEP_256, Jose.JweEncryption.A256GCM, jwtSettings);
when i try do decrypt the payload, i'm getting this error: specified padding mode is not valid for this algorithm.
the specific part of code that is throwing this exception is the:
byte[] cek = keyManagement.Unwrap(encryptedCek, key, jweAlgorithm.KeySize, header);
the implementation of RsaOaep256KeyManagement is doing this:
return Ensure.Type<RSA>(key, "RsaKeyManagement algorithm expects key to be of RSA type.").Decrypt(encryptedCek, RSAEncryptionPadding.OaepSHA256);
it seens that paddind mode is right, anyone have an idea to how fix this error?
I want to use HERE map api's in my project.
As per their document, I need to use generate the signature first using Oauth 1.0 HMAC-256.
I am following below AAA sdk by HERE map :
https://github.com/heremaps/here-aaa-java-sdk/blob/master/here-oauth-client/src/main/java/com/here/account/auth/SignatureCalculator.java
SignatureCalculator signatureCalculator = new SignatureCalculator(CONSUMER_KEY,CONSUMER_SECRET);
String signature = signatureCalculator.calculateSignature("GET","https://account.api.here.com/oauth2/token",
(System.currentTimeMillis()/1000L),RandomStringUtils.randomAlphanumeric(12),
SignatureMethod.HMACSHA256,null,null);
But I am not able to generate the token using this signature. I got below error :
{"errorId":"ERROR-25b51579-57d0-4873-b82e-466519b8b6a4","httpStatus":401,"errorCode":401202,"message":"Invalid Client Authorization header, expecting signed request format.","error":"invalid_request","error_description":"errorCode: '401202'. Invalid Client Authorization header, expecting signed request format."}
When i try to do same through postman then everything works perfect.
There is difference between both the signature (generated though postman which works / generated though java code)
pw7d5IVYFsYH0zNPNZJU7x3T6LUtDj8zzYw2hsUUlM= . -- Not Working. Generated using AAA here library.
tBWyomfDmgihh2kC%2B14qYurOoPF%2FYkpg7QyGpwgZ77A%3D" -- Working Signature , generated through postman
I think I am doing wrong signature generation.
You have to done signature encoding by URLEncoding in UTF-8 format.
URLEncoder.encode("Signature_Generated_from_HMAC-SHA256","UTF-8")
Recently, I was able to get MD5 authentication working for XMPP streams in Swift IOS following the instructions on the following two websites (I used the CC-MD5 function of Apple's CommonCrypto C library for the actual hashing):
http://wiki.xmpp.org/web/SASLandDIGEST-MD5
http://www.deusty.com/2007/09/example-please.html
I'm searching for a similar explanation for how to get other hashed SASL authentication schemes working, especially SCRAM-SHA1. I have found the official RFC5802 document but I'm having a lot of trouble understanding it (it is not specific to XMPP either). I would appreciate a simpler explanation or some simple readable code (C, PHP, C++, Javascript, Java) specific to XMPP authentication that doesn't use libraries for anything other than the actual hashing.
I'm interested in understanding the process and am not looking to use the ios XMPP-Framework. Any help would be appreciated.
SCRAM-SHA-1
The basic overview of how this mechanism works is:
The client sends the username it wants to authenticate as.
The server sends back the salt for that user and the number of iterations (either by generating them or looking them up in its database for the given username).
The client hashes the password with the given salt for the given number of iterations.
The client sends the result back.
The server does a variation of the hashing and sends it result back to the client, so the client can also verify that the server had the password/a hash of the password.
The cryptographic algorithms you'll need are SHA-1, HMAC with SHA-1 and PBKDF2 with SHA-1. You should look up how to use them in your language/framework, as I don't recommend implementing them from scratch.
In detail
First normalize the password (using SASLprep), this will be normalizedPassword. This is to ensure the UTF8 encoding can't contain variations of the same password.
Pick a random string (for example 32 hex encoded bytes). This will be clientNonce.
The initialMessage is "n=" .. username .. ",r=" .. clientNonce (I'm using .. for string concatenation).
The client prepends the GS2 header ("n,,") to the initialMessage and base64-encodes the result. It sends this as its first message:
<auth xmlns="urn:ietf:params:xml:ns:xmpp-sasl" mechanism="SCRAM-SHA-1">
biwsbj1yb21lbyxyPTZkNDQyYjVkOWU1MWE3NDBmMzY5ZTNkY2VjZjMxNzhl
</auth>
The server responds with a challenge. The data of the challenge is base64 encoded:
<challenge xmlns="urn:ietf:params:xml:ns:xmpp-sasl">
cj02ZDQ0MmI1ZDllNTFhNzQwZjM2OWUzZGNlY2YzMTc4ZWMxMmIzOTg1YmJkNGE4ZTZmODE0YjQyMmFiNzY2NTczLHM9UVNYQ1IrUTZzZWs4YmY5MixpPTQwOTY=
</challenge>
The client base64 decodes it:
r=6d442b5d9e51a740f369e3dcecf3178ec12b3985bbd4a8e6f814b422ab766573,s=QSXCR+Q6sek8bf92,i=4096
The client parses this:
r= This is the serverNonce. The client MUST ensure that it starts with the clientNonce it sent in its initial message.
s= This is the salt, base64 encoded (yes, this is base64-encoded twice!)
i= This is the number of iterations, i.
The client computes:
clientFinalMessageBare = "c=biws,r=" .. serverNonce
saltedPassword = PBKDF2-SHA-1(normalizedPassword, salt, i)
clientKey = HMAC-SHA-1(saltedPassword, "Client Key")
storedKey = SHA-1(clientKey)
authMessage = initialMessage .. "," .. serverFirstMessage .. "," .. clientFinalMessageBare
clientSignature = HMAC-SHA-1(storedKey, authMessage)
clientProof = clientKey XOR clientSignature
serverKey = HMAC-SHA-1(saltedPassword, "Server Key")
serverSignature = HMAC-SHA-1(serverKey, authMessage)
clientFinalMessage = clientFinalMessageBare .. ",p=" .. base64(clientProof)
The client base64 encodes the clientFinalMessage and sends it as a response:
<response xmlns="urn:ietf:params:xml:ns:xmpp-sasl">
Yz1iaXdzLHI9NmQ0NDJiNWQ5ZTUxYTc0MGYzNjllM2RjZWNmMzE3OGVjMTJiMzk4NWJiZDRhOGU2ZjgxNGI0MjJhYjc2NjU3MyxwPXlxbTcyWWxmc2hFTmpQUjFYeGFucG5IUVA4bz0=
</response>
If everything went well, you'll get a <success> response from the server:
<success xmlns='urn:ietf:params:xml:ns:xmpp-sasl'>
dj1wTk5ERlZFUXh1WHhDb1NFaVc4R0VaKzFSU289
</success>
Base64 decoded this contains:
v=pNNDFVEQxuXxCoSEiW8GEZ+1RSo=
The client MUST make sure the value of v is the base64 encoding of the serverSignature.
Extras
This is the basic version of the algorithm. You can extend it to do:
Channel binding. This mixes in some information from the TLS connection to the procedure to prevent MitM attacks.
Hashed storage. If the server always sends the same salt and i values, then the client can store only saltedPassword instead of the user's password. This is more secure (as the client doesn't need to store the password, just a hard to reverse salted hash) and faster, as the client doesn't need to do all the key stretching every time.
The server can also use hashed storage: the server can store only salt, i, storedKey and serverKey. More info on that here.
Possibly, also adding SCRAM-SHA-256 (though server support seems non-existent).
Pitfalls
Some common pitfalls:
Don't assume anything about the length of the nonces or salt (though if you generate them, make sure they are long enough and cryptographically random).
The salt is base64 encoded and can contain any data (embedded NULs).
Not using SASLprep may work fine for people using ASCII passwords, but it may completely break logging in for people using other scripts.
The initialMessage part of the authMessage does not include the GS2 header (in most situations, this is "n,,").
Test vectors
If you want to test your implementation, here are all the intermediate results for the example from the RFC:
Username: user
Password: pencil
Client generates the random nonce fyko+d2lbbFgONRv9qkxdawL
Initial message: n,,n=user,r=fyko+d2lbbFgONRv9qkxdawL
Server generates the random nonce 3rfcNHYJY1ZVvWVs7j
Server replies: r=fyko+d2lbbFgONRv9qkxdawL3rfcNHYJY1ZVvWVs7j,s=QSXCR+Q6sek8bf92,i=4096
The salt (hex): 4125c247e43ab1e93c6dff76
Client final message bare: c=biws,r=fyko+d2lbbFgONRv9qkxdawL3rfcNHYJY1ZVvWVs7j
Salted password (hex): 1d96ee3a529b5a5f9e47c01f229a2cb8a6e15f7d
Client key (hex): e234c47bf6c36696dd6d852b99aaa2ba26555728
Stored key (hex): e9d94660c39d65c38fbad91c358f14da0eef2bd6
Auth message: n=user,r=fyko+d2lbbFgONRv9qkxdawL,r=fyko+d2lbbFgONRv9qkxdawL3rfcNHYJY1ZVvWVs7j,s=QSXCR+Q6sek8bf92,i=4096,c=biws,r=fyko+d2lbbFgONRv9qkxdawL3rfcNHYJY1ZVvWVs7j
Client signature (hex): 5d7138c486b0bfabdf49e3e2da8bd6e5c79db613
Client proof (hex): bf45fcbf7073d93d022466c94321745fe1c8e13b
Server key (hex): 0fe09258b3ac852ba502cc62ba903eaacdbf7d31
Server signature (hex): ae617da6a57c4bbb2e0286568dae1d251905b0a4
Client final message: c=biws,r=fyko+d2lbbFgONRv9qkxdawL3rfcNHYJY1ZVvWVs7j,p=v0X8v3Bz2T0CJGbJQyF0X+HI4Ts=
Server final message: v=rmF9pqV8S7suAoZWja4dJRkFsKQ=
Server's server signature (hex): ae617da6a57c4bbb2e0286568dae1d251905b0a4
I am signing some data with a self signed X509Certificate in c#. Signature results as a binary byte[]. I want to save this signature to a pkcs#7 format file with extenstion .p7b. When I save this using FileStream as required. It generates an invalid p7b file.
Can anyone help save this signature as a valid external file? Or point out if there is something wrong with the approach?
// EDIT: Adding the code as asked by Eugene Mayevski
// Open Store Location & fetch certificate
X509Store store = new X509Store(StoreName.My, StoreLocation.CurrentUser);
store.Open(OpenFlags.ReadWrite);
X509Certificate2Collection certifcates = store.Certificates;
X509Certificate2 certificate = certifcates[0];`
// fetch private key
string publicKeyString = certificate.GetPublicKeyString();
RSACryptoServiceProvider privateKey = certificate.PrivateKey as RSACryptoServiceProvider;
// get binary of data & sign it.
byte[] buffer = Encoding.Default.GetBytes("Sample data to sign. Although it would be a document.");
byte[] signature = privateKey.SignData(buffer, new SHA1Managed());
You are not generating a Cryptographic Message Syntax (CMS) message format which is defined in PKCS#7. You generate just the signature, which can be placed in the container format.
To create a CMS formatted message yourself, please take a look at the Microsoft documentation or use the C# version of Bouncy Castle.
I'm writing an iPad game that sends hi-score type data (ie data beyond what Game Center supports) to a Google appengine datastore. It sends these updates via http GET or POST requests, such as http://myapp.appspot.com/game/hiscore/925818
Here is how I thought to ensure the appengine datastore isn't spammed with false data.
zip/encrypt the payload data using hardcoded p#ssw0rd saved in the iOS binary. Encode that binary data as base64. Pass base64 payload in the url query string or in the POST data. At handler, unbase64, then unzip data with p#ssw0rd. Follow instructions in payload to update highscore-type data.
CON: If p#ssw0rd is somehow derived from the iOS binary, this scheme can be defeated.
Is this adequate/sufficient? Is there another way to do this?
There is absolutely no way to make sure it's your client that sends the data. All you can try is to obfuscate some thing to make it harder for spammers to submit data.
However I think there are two thing you can do:
Have some kind of secrect key saved in the binary
Have a custom algorithm calculating some checksum
Maybe you can go with a combination of both. Let me give you an example:
Create some custom (complex!) alorithm like (simplyfied):
var result = ((score XOR score / 5) XOR score * 8) BITSHIFT_BY 3
Then use your static stored key with that result and a well known hash function like:
var hash = SHA256(StaticKey + result)
Then send that hash with the score to the server. The server has to "validate" the hash by performing the exact same steps (evaluate algorithm + do the SHA256 stuff) and compare the hashes. If they match the score hopefully comes from your app otherwise throw it away, it comes from a spammer.
However this is only one thing you can do. Have a look at the link from mfanto, there are many other ideas that you can look at.
Be sure to not tell anybody about how you're doing it since this is security through obscurity.
Ok me, there are 2 methods to do this.
1) Purchase an SSL certificate for $FREE.99 and open HTTPS connections only to your server to submit hiscore type data. Connection speed should be around 500 ms due to handshake roundtrip time.
2) Embed an RSA public key certificate in your iOS app, and have the RSA private key on your server.
You can then do 1 of 2 things with this second scheme:
IF your data messages are really small (≤256 B) you can just encrypt and send 256B packages (RSA payload is limited by the number of bits in the key)
ELSE IF the data is too large (>256B), generate a random symmetric key (AES), and pack:
SYMMETRIC AES KEY ENCRYPTED WITH RSA PUBLIC KEY
BINARY DATA ENCODED WITH SYMMETRIC AES KEY
The server then takes the first 256 bytes and decodes it, then the server uses that AES key to decrypt the rest of the message.
The above 2 only prevent eavesdropping, but it means the data format of your messages is hidden. At some level, it is still a type of security by obscurity, since if the hacker has your public key AND your message format, they can manufacture messages.