DSA_dup_DH 3 2003-07-24 0.9.9-dev OpenSSL

### NAME

DSA_dup_DH - create a DH structure out of DSA structure

### LIBRARY

libcrypto, -lcrypto

### SYNOPSIS

     #include

     DH * DSA_dup_DH(const DSA *r);

### DESCRIPTION

DSA_dup_DH() duplicates DSA parameters/keys as DH parameters/keys. q is lost during that conversion, but the resulting DH parameters contain its length.

### RETURN VALUE

DSA_dup_DH() returns the new DH structure, and NULL on error. The error codes can be obtained by ERR_get_error(3).

### NOTE

Be careful to avoid small subgroup attacks when using this.

### SEE ALSO

openssl_dh(3), openssl_dsa(3), ERR_get_error(3)

### HISTORY

DSA_dup_DH() was added in OpenSSL 0.9.4.