Index: openssl/doc/crypto/EVP_PKEY_keygen.pod |
=================================================================== |
--- openssl/doc/crypto/EVP_PKEY_keygen.pod (revision 0) |
+++ openssl/doc/crypto/EVP_PKEY_keygen.pod (revision 0) |
@@ -0,0 +1,161 @@ |
+=pod |
+ |
+=head1 NAME |
+ |
+EVP_PKEY_keygen_init, EVP_PKEY_keygen, EVP_PKEY_paramgen_init, EVP_PKEY_paramgen, EVP_PKEY_CTX_set_cb, EVP_PKEY_CTX_get_cb, EVP_PKEY_CTX_get_keygen_info, EVP_PKEVP_PKEY_CTX_set_app_data, EVP_PKEY_CTX_get_app_data - key and parameter generation functions |
+ |
+=head1 SYNOPSIS |
+ |
+ #include <openssl/evp.h> |
+ |
+ int EVP_PKEY_keygen_init(EVP_PKEY_CTX *ctx); |
+ int EVP_PKEY_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey); |
+ int EVP_PKEY_paramgen_init(EVP_PKEY_CTX *ctx); |
+ int EVP_PKEY_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY **ppkey); |
+ |
+ typedef int EVP_PKEY_gen_cb(EVP_PKEY_CTX *ctx); |
+ |
+ void EVP_PKEY_CTX_set_cb(EVP_PKEY_CTX *ctx, EVP_PKEY_gen_cb *cb); |
+ EVP_PKEY_gen_cb *EVP_PKEY_CTX_get_cb(EVP_PKEY_CTX *ctx); |
+ |
+ int EVP_PKEY_CTX_get_keygen_info(EVP_PKEY_CTX *ctx, int idx); |
+ |
+ void EVP_PKEY_CTX_set_app_data(EVP_PKEY_CTX *ctx, void *data); |
+ void *EVP_PKEY_CTX_get_app_data(EVP_PKEY_CTX *ctx); |
+ |
+=head1 DESCRIPTION |
+ |
+The EVP_PKEY_keygen_init() function initializes a public key algorithm |
+context using key B<pkey> for a key genration operation. |
+ |
+The EVP_PKEY_keygen() function performs a key generation operation, the |
+generated key is written to B<ppkey>. |
+ |
+The functions EVP_PKEY_paramgen_init() and EVP_PKEY_paramgen() are similar |
+except parameters are generated. |
+ |
+The function EVP_PKEY_set_cb() sets the key or parameter generation callback |
+to B<cb>. The function EVP_PKEY_CTX_get_cb() returns the key or parameter |
+generation callback. |
+ |
+The function EVP_PKEY_CTX_get_keygen_info() returns parameters associated |
+with the generation operation. If B<idx> is -1 the total number of |
+parameters available is returned. Any non negative value returns the value of |
+that parameter. EVP_PKEY_CTX_gen_keygen_info() with a non-negative value for |
+B<idx> should only be called within the generation callback. |
+ |
+If the callback returns 0 then the key genration operation is aborted and an |
+error occurs. This might occur during a time consuming operation where |
+a user clicks on a "cancel" button. |
+ |
+The functions EVP_PKEY_CTX_set_app_data() and EVP_PKEY_CTX_get_app_data() set |
+and retrieve an opaque pointer. This can be used to set some application |
+defined value which can be retrieved in the callback: for example a handle |
+which is used to update a "progress dialog". |
+ |
+=head1 NOTES |
+ |
+After the call to EVP_PKEY_keygen_init() or EVP_PKEY_paramgen_init() algorithm |
+specific control operations can be performed to set any appropriate parameters |
+for the operation. |
+ |
+The functions EVP_PKEY_keygen() and EVP_PKEY_paramgen() can be called more than |
+once on the same context if several operations are performed using the same |
+parameters. |
+ |
+The meaning of the parameters passed to the callback will depend on the |
+algorithm and the specifiic implementation of the algorithm. Some might not |
+give any useful information at all during key or parameter generation. Others |
+might not even call the callback. |
+ |
+The operation performed by key or parameter generation depends on the algorithm |
+used. In some cases (e.g. EC with a supplied named curve) the "generation" |
+option merely sets the appropriate fields in an EVP_PKEY structure. |
+ |
+In OpenSSL an EVP_PKEY structure containing a private key also contains the |
+public key components and parameters (if any). An OpenSSL private key is |
+equivalent to what some libraries call a "key pair". A private key can be used |
+in functions which require the use of a public key or parameters. |
+ |
+=head1 RETURN VALUES |
+ |
+EVP_PKEY_keygen_init(), EVP_PKEY_paramgen_init(), EVP_PKEY_keygen() and |
+EVP_PKEY_paramgen() return 1 for success and 0 or a negative value for failure. |
+In particular a return value of -2 indicates the operation is not supported by |
+the public key algorithm. |
+ |
+=head1 EXAMPLES |
+ |
+Generate a 2048 bit RSA key: |
+ |
+ #include <openssl/evp.h> |
+ #include <openssl/rsa.h> |
+ |
+ EVP_PKEY_CTX *ctx; |
+ EVP_PKEY *pkey = NULL; |
+ ctx = EVP_PKEY_CTX_new_id(EVP_PKEY_RSA, NULL); |
+ if (!ctx) |
+ /* Error occurred */ |
+ if (EVP_PKEY_keygen_init(ctx) <= 0) |
+ /* Error */ |
+ if (EVP_PKEY_CTX_set_rsa_keygen_bits(ctx, 2048) <= 0) |
+ /* Error */ |
+ |
+ /* Generate key */ |
+ if (EVP_PKEY_keygen(ctx, &pkey) <= 0) |
+ /* Error */ |
+ |
+Generate a key from a set of parameters: |
+ |
+ #include <openssl/evp.h> |
+ #include <openssl/rsa.h> |
+ |
+ EVP_PKEY_CTX *ctx; |
+ EVP_PKEY *pkey = NULL, *param; |
+ /* Assumed param is set up already */ |
+ ctx = EVP_PKEY_CTX_new(param); |
+ if (!ctx) |
+ /* Error occurred */ |
+ if (EVP_PKEY_keygen_init(ctx) <= 0) |
+ /* Error */ |
+ |
+ /* Generate key */ |
+ if (EVP_PKEY_keygen(ctx, &pkey) <= 0) |
+ /* Error */ |
+ |
+Example of generation callback for OpenSSL public key implementations: |
+ |
+ /* Application data is a BIO to output status to */ |
+ |
+ EVP_PKEY_CTX_set_app_data(ctx, status_bio); |
+ |
+ static int genpkey_cb(EVP_PKEY_CTX *ctx) |
+ { |
+ char c='*'; |
+ BIO *b = EVP_PKEY_CTX_get_app_data(ctx); |
+ int p; |
+ p = EVP_PKEY_CTX_get_keygen_info(ctx, 0); |
+ if (p == 0) c='.'; |
+ if (p == 1) c='+'; |
+ if (p == 2) c='*'; |
+ if (p == 3) c='\n'; |
+ BIO_write(b,&c,1); |
+ (void)BIO_flush(b); |
+ return 1; |
+ } |
+ |
+=head1 SEE ALSO |
+ |
+L<EVP_PKEY_CTX_new(3)|EVP_PKEY_CTX_new(3)>, |
+L<EVP_PKEY_encrypt(3)|EVP_PKEY_encrypt(3)>, |
+L<EVP_PKEY_decrypt(3)|EVP_PKEY_decrypt(3)>, |
+L<EVP_PKEY_sign(3)|EVP_PKEY_sign(3)>, |
+L<EVP_PKEY_verify(3)|EVP_PKEY_verify(3)>, |
+L<EVP_PKEY_verifyrecover(3)|EVP_PKEY_verifyrecover(3)>, |
+L<EVP_PKEY_derive(3)|EVP_PKEY_derive(3)> |
+ |
+=head1 HISTORY |
+ |
+These functions were first added to OpenSSL 1.0.0. |
+ |
+=cut |