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diff --git a/src/lib/libcrypto/doc/DH_set_method.pod b/src/lib/libcrypto/doc/DH_set_method.pod
new file mode 100644
index 0000000000..d990bf8786
--- /dev/null
+++ b/src/lib/libcrypto/doc/DH_set_method.pod
@@ -0,0 +1,111 @@
+=pod
+
+=head1 NAME
+
+DH_set_default_openssl_method, DH_get_default_openssl_method,
+DH_set_method, DH_new_method, DH_OpenSSL - select DH method
+
+=head1 SYNOPSIS
+
+ #include <openssl/dh.h>
+ #include <openssl/engine.h>
+
+ void DH_set_default_openssl_method(DH_METHOD *meth);
+
+ DH_METHOD *DH_get_default_openssl_method(void);
+
+ int DH_set_method(DH *dh, ENGINE *engine);
+
+ DH *DH_new_method(ENGINE *engine);
+
+ DH_METHOD *DH_OpenSSL(void);
+
+=head1 DESCRIPTION
+
+A B<DH_METHOD> specifies the functions that OpenSSL uses for Diffie-Hellman
+operations. By modifying the method, alternative implementations
+such as hardware accelerators may be used.
+
+Initially, the default is to use the OpenSSL internal implementation.
+DH_OpenSSL() returns a pointer to that method.
+
+DH_set_default_openssl_method() makes B<meth> the default method for all DH
+structures created later. B<NB:> This is true only whilst the default engine
+for Diffie-Hellman operations remains as "openssl". ENGINEs provide an
+encapsulation for implementations of one or more algorithms, and all the DH
+functions mentioned here operate within the scope of the default
+"openssl" engine.
+
+DH_get_default_openssl_method() returns a pointer to the current default
+method for the "openssl" engine.
+
+DH_set_method() selects B<engine> as the engine that will be responsible for
+all operations using the structure B<dh>. If this function completes successfully,
+then the B<dh> structure will have its own functional reference of B<engine>, so
+the caller should remember to free their own reference to B<engine> when they are
+finished with it. NB: An ENGINE's DH_METHOD can be retrieved (or set) by
+ENGINE_get_DH() or ENGINE_set_DH().
+
+DH_new_method() allocates and initializes a DH structure so that
+B<engine> will be used for the DH operations. If B<engine> is NULL,
+the default engine for Diffie-Hellman opertaions is used.
+
+=head1 THE DH_METHOD STRUCTURE
+
+ typedef struct dh_meth_st
+ {
+     /* name of the implementation */
+        const char *name;
+
+     /* generate private and public DH values for key agreement */
+        int (*generate_key)(DH *dh);
+
+     /* compute shared secret */
+        int (*compute_key)(unsigned char *key, BIGNUM *pub_key, DH *dh);
+
+     /* compute r = a ^ p mod m (May be NULL for some implementations) */
+        int (*bn_mod_exp)(DH *dh, BIGNUM *r, BIGNUM *a, const BIGNUM *p,
+                                const BIGNUM *m, BN_CTX *ctx,
+                                BN_MONT_CTX *m_ctx);
+
+     /* called at DH_new */
+        int (*init)(DH *dh);
+
+     /* called at DH_free */
+        int (*finish)(DH *dh);
+
+        int flags;
+
+        char *app_data; /* ?? */
+
+ } DH_METHOD;
+
+=head1 RETURN VALUES
+
+DH_OpenSSL() and DH_get_default_openssl_method() return pointers to the
+respective B<DH_METHOD>s.
+
+DH_set_default_openssl_method() returns no value.
+
+DH_set_method() returns non-zero if the ENGINE associated with B<dh>
+was successfully changed to B<engine>.
+
+DH_new_method() returns NULL and sets an error code that can be
+obtained by L<ERR_get_error(3)|ERR_get_error(3)> if the allocation fails.
+Otherwise it returns a pointer to the newly allocated structure.
+
+=head1 SEE ALSO
+
+L<dh(3)|dh(3)>, L<DH_new(3)|DH_new(3)>
+
+=head1 HISTORY
+
+DH_set_default_method(), DH_get_default_method(), DH_set_method(),
+DH_new_method() and DH_OpenSSL() were added in OpenSSL 0.9.4.
+
+DH_set_default_openssl_method() and DH_get_default_openssl_method()
+replaced DH_set_default_method() and DH_get_default_method() respectively,
+and DH_set_method() and DH_new_method() were altered to use B<ENGINE>s
+rather than B<DH_METHOD>s during development of OpenSSL 0.9.6.
+
+=cut