asn.1

I am trying to build a correctly formatted GET PROCESSING OPTIONS command to be sent to a contactless EMV card. This post has been very helpful but I just need to know a little more detail. When parsing the PDOL, is it safe to assume that each tag is 2 bytes in length, followed by the size of the data expected in return? For example, the PDOL 9F66049F02069F37049F1A02 is broken into 9F66 04 , 9F02 06 , etc. each with 2 byte tags and 1 byte for the expected length of the data value. Is it safe to assume that each tag is 2 bytes in length when parsing? No, you can't expect that each tag consists

I'm writing an app to get a better understanding of DKIM. The spec says I retrieve a "ASN.1 DER-encoded" public key from the domain TXT record. I can seen the key on "s1024._domainkey.yahoo.com" = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDrEee0Ri4Juz+QfiWYui/E9UGSXau/2P8LjnTD8V4Unn+2FAZVGE3kL23bzeoULYv4PeleB3gfm". How can I use this key from .net? The examples I've seen get the key from a X509Certificate2, or an XML file containing the RSAParameters. CORRECTION : I copy/pasted the key above from the network-tools.com DNS tool, which must've cut it short. nslookup gives me the full key: s1024.

I am working on an iPhone app that retrieves an RSA public key from an ASP.NET web service in the form: <RSAKeyValue> <Modulus>qdd0paiiBJ+xYaN4TKDdbEzrJJw9xlbRAltb5OPdegjLoW60yOjL/sni52WVsGC9QxpNitZR33dnUscmI0cTJoxkXypPjbD94UpH+p4el2tuKBypHlE7bERApuUp55y8BiRkbQNFH8smZFWDwtIc/PsJryeGf8fAryel8c5V3PU=</Modulus> <Exponent>AQAB</Exponent> </RSAKeyValue> I need to then convert this response into an NSData * of the appropriate format (from some intense Googling, most likely 'ASN.1 DER' binary format. I've got code in place to convert both parts from their Base64 representations to the original binary

I have generated an ECDSA signature in Java and I would like to get the R and S values from it. It is my understanding that the signature I have generated is DER encoded. Can someone please provide me with some Java code (maybe using Bouncy Castle) to retrieve the R and S values as BigIntegers? Note: In case it helps, I generated the signature using a built in provider via the JCE's Signature class and the signature lengths for my P_256 EC key pair hover between 70 and 72 bytes usually. I was able to solve this myself. In case it helps anyone here is how I did it (most exception handling has

This code relates to DKIM signature verification used in anti-spam efforts. I have a byte[] from s1024._domainkey.yahoo.com that is ASN.1 encoded, but I don't know if that alone contains enough information to materialize a public key. Based on this class , it appears I can convert an ASN.1 key into a X509Certificate Public key, but I need to supply an OID and some ASN.1-encoded parameters. In this example I have metadata that the ASN1 key is: An RSA encoded key (ASN.1 DER-encoded [ITU-X660-1997] RSAPublicKey per RFC3447) Used with either sha1 sha256 hash algorithms Uses an OID relating to the

I have binary ASN.1 data objects I need to parse into my Java project. I just want the ASN.1 structure and data as it is parsed for example by the BER viewer: The ASN.1 parser of BouncyCastle is not able to parse this structure (only returns application specific binary data type). What ASN.1 library can I use to get such a result? Does anybody has sample code that demonstrates how to parse an ASN.1 object? BTW: I also tried several free ASN.1 Java compilers but none is able to generate working Java code given may ASN.1 specification. I have to correct myself - it is possible to read out the

According to the X.509, a certificate has an attribute subject. C=US, ST=Maryland, L=Pasadena, O=Brent Baccala, OU=FreeSoft, CN=www.freesoft.org/emailAddress=baccala@freesoft.org This is the typical subject value. The question is what are the types(or tags) of those attributes(C, ST, L, O, OU, CN) and what is their format? Mathias Brossard IETF PKIX (latest version RFC 5280 ) is a well accepted profile for certificates. From section 4.1.2.4, the following fields must be supported (I've added between parenthesis is the OpenSSL long and optional short name): country (countryName, C),

All of these provide binary serialization, RPC frameworks and IDL. I'm interested in key differences between them and characteristics (performance, ease of use, programming languages support). If you know any other similar technologies, please mention it in an answer. JUST MY correct OPINION ASN.1 is an ISO/ISE standard. It has a very readable source language and a variety of back-ends, both binary and human-readable. Being an international standard (and an old one at that!) the source language is a bit kitchen-sinkish (in about the same way that the Atlantic Ocean is a bit wet) but it is