Re: OAEP for signatures and PSS

Philippe Stellwag wrote: Dr. Stephen Henson wrote: On Fri, Jun 08, 2007, Philippe Stellwag wrote: Can I use PSS with openssl on command line, like OAEP? I cannot find any options. Yes but only in 0.9.9-dev. There you can use PSS with either the dgst utility or the pkeyutl utility (which

Re: OAEP for signatures and PSS

Dr. Stephen Henson wrote: On Fri, Jun 08, 2007, Philippe Stellwag wrote: Can I use PSS with openssl on command line, like OAEP? I cannot find any options. Yes but only in 0.9.9-dev. There you can use PSS with either the dgst utility or the pkeyutl utility (which is a generalized version

Re: OAEP for signatures and PSS

tp://citeseer.ist.psu.edu/bellare94optimal.html > > > On 6/8/07, Philippe Stellwag <[EMAIL PROTECTED]> wrote: > > > > Hi @ll, > > > > is it a security problem to use RSA-OAEP padding for RSA > > signatures? > > > > Is RSA-PSS n

OAEP for signatures and PSS

Hi @ll, is it a security problem to use RSA-OAEP padding for RSA signatures? Is RSA-PSS new to OpenSSL and how can I use it? What's the security difference(s) between RSA-OAEP and RSA-PSS? Thanks. Philippe -- OAEP: Optimal Asymmetric Encoding Padding PSS: Probabilistic Signature Scheme ___

Re: RSA library and block size

* Marek Marcola wrote: That means, that padding didn't solve the problem of known-plaintext-, chosen-plaintext-, chosen-cyphertext- or adaptive-chosen-plaintext-attacks? What about OAEP padding? Can I use the public key as secret key and backwards? Then I can use OAEP for "signing" with the s

Re: RSA library and block size

* Philippe Stellwag <[EMAIL PROTECTED]> wrote: > > That means, that padding didn't solve the problem of > known-plaintext-, chosen-plaintext-, chosen-cyphertext- or > adaptive-chosen-plaintext-attacks? What about OAEP padding? Can I use the public key as secret key and ba

Re: RSA library and block size

* Marek Marcola <[EMAIL PROTECTED]> wrote: > > Maybe I do not understand this correctly, but if you want to > encrypt some data with RSA 1024 bit key then you will get 128 > bytes of output ciphertext. It is not important what padding > scheme you will use (or even no padding at all) you should

Re: RSA library and block size

* Marek Marcola wrote: [...] Or maybe you can send your data in two smaller RSA encrypted messages ? I just want to store some authentication data - a username, group and date - on a "token", which only offers a passive storage (116 byte EEPROM) without any cryptografic functions, to sav

Re: RSA library and block size

* David Schwartz wrote: But can I use e.g. a 1024 bit key pair with a block size of 116 byte, that is not depending on the problem shown above, isn't it?! What is the security reason, why not to do this? That would seriously weaken the security properties. http://en.wikipedia.org/wiki/RSA

Re: RSA library and block size

* Marek Marcola wrote: * Philippe Stellwag wrote: is it possible to change the OpenSSL RSA functions so that I can use a different - may be a variable - block size. At the moment the block size on the OpenSSL RSA functions depends on the length of the RSA key pair and the kind of padding

RSA library and block size

Hi at all, is it possible to change the OpenSSL RSA functions so that I can use a different - may be a variable - block size. At the moment the block size on the OpenSSL RSA functions depends on the length of the RSA key pair and the kind of padding (following PKCS#1 v1.5, which means 11