Manual Pages for UNIX Operating System command usage for man RSA_public_decrypt

OpenSSL                             RSA_private_encrypt(3openssl)



NNNNAAAAMMMMEEEE
     RSA_private_encrypt, RSA_public_decrypt - low level
     signature operations

SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
      #include 

      int RSA_private_encrypt(int flen, unsigned char *from,
         unsigned char *to, RSA *rsa, int padding);

      int RSA_public_decrypt(int flen, unsigned char *from,
         unsigned char *to, RSA *rsa, int padding);


DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     These functions handle RSA signatures at a low level.

     RSA_private_encrypt() signs the fffflllleeeennnn bytes at ffffrrrroooommmm (usually
     a message digest with an algorithm identifier) using the
     private key rrrrssssaaaa and stores the signature in ttttoooo. ttttoooo must
     point to RRRRSSSSAAAA_ssssiiiizzzzeeee((((rrrrssssaaaa)))) bytes of memory.

     ppppaaaaddddddddiiiinnnngggg denotes one of the following modes:

     RSA_PKCS1_PADDING
         PKCS #1 v1.5 padding. This function does not handle the
         aaaallllggggoooorrrriiiitttthhhhmmmmIIIIddddeeeennnnttttiiiiffffiiiieeeerrrr specified in PKCS #1. When
         generating or verifying PKCS #1 signatures, RSA_sign(3)
         and RSA_verify(3) should be used.

     RSA_NO_PADDING
         Raw RSA signature. This mode should only be used to
         implement cryptographically sound padding modes in the
         application code.  Signing user data directly with RSA
         is insecure.

     RSA_public_decrypt() recovers the message digest from the
     fffflllleeeennnn bytes long signature at ffffrrrroooommmm using the signer's public
     key rrrrssssaaaa. ttttoooo must point to a memory section large enough to
     hold the message digest (which is smaller than RRRRSSSSAAAA_ssssiiiizzzzeeee((((rrrrssssaaaa))))
     ---- 11111111). ppppaaaaddddddddiiiinnnngggg is the padding mode that was used to sign the
     data.

RRRREEEETTTTUUUURRRRNNNN VVVVAAAALLLLUUUUEEEESSSS
     RSA_private_encrypt() returns the size of the signature
     (i.e., RSA_size(rsa)). RSA_public_decrypt() returns the size
     of the recovered message digest.

     On error, -1 is returned; the error codes can be obtained by
     ERR_get_error(3).





25/Sep/2002            Last change: 0.9.8o                      1






OpenSSL                             RSA_private_encrypt(3openssl)



SSSSEEEEEEEE AAAALLLLSSSSOOOO
     ERR_get_error(3), rsa(3), RSA_sign(3), RSA_verify(3)

HHHHIIIISSSSTTTTOOOORRRRYYYY
     The ppppaaaaddddddddiiiinnnngggg argument was added in SSLeay 0.8. RSA_NO_PADDING
     is available since SSLeay 0.9.0.

















































25/Sep/2002            Last change: 0.9.8o                      2