Index for Section 3

Alphabetical listing for R

Bottom of page

RSA_generate_key(3)
NAME
  RSA_generate_key - Generate RSA key pair

SYNOPSIS
  #include <openssl/rsa.h>

  RSA *RSA_generate_key(
	  int num,
	  unsigned long e,
	  void ((*callback)(int,int,void *)),
	  void *cb_arg );

DESCRIPTION
  The RSA_generate_key() function generates a key pair and returns it in a
  newly allocated RSA structure. The pseudo-random number generator must be
  seeded prior to calling RSA_generate_key().

  The modulus size will be num bits, and the public exponent will be e. Key
  sizes with num < 1024 should be considered insecure. The exponent is an odd
  number, typically 3, 17 or 65537.

  A callback function may be used to provide feedback about the progress of
  the key generation. If callback is not NULL, it will be called as follows:

    ·  While a random prime number is generated, it is called as described in
       BN_generate_prime(3).

    ·  When the n-th randomly generated prime is rejected as not suitable for
       the key, callback(2, n, cb_arg) is called.

    ·  When a random p has been found with p-1 relatively prime to e, it is
       called as callback(3, 0, cb_arg).

  The process is then repeated for prime q with callback(3, 1, cb_arg).

RESTRICTIONS
  callback(2, x, cb_arg) is used with two different meanings.

  The RSA_generate_key() function goes into an infinite loop for illegal
  input values.

RETURN VALUE
  If key generation fails, RSA_generate_key() returns NULL; the error codes
  can be obtained by using the ERR_get_error() function.

HISTORY
  The cb_arg argument was added in SSLeay 0.9.0.

SEE ALSO
  Functions: err(3),  rand_ssl(3),  rsa(3),  RSA_free(3)

Index for Section 3

Alphabetical listing for R

Top of page