4 files changed, 21 insertions, 5 deletions
diff --git a/src/_cffi_src/openssl/bio.py b/src/_cffi_src/openssl/bio.py
index c032f72a..df9b1b48 100644
--- a/src/_cffi_src/openssl/bio.py
+++ b/src/_cffi_src/openssl/bio.py
@@ -68,8 +68,6 @@ static const int BIO_CTRL_WPENDING;
 static const int BIO_C_FILE_SEEK;
 static const int BIO_C_FILE_TELL;
 static const int BIO_TYPE_NONE;
-static const int BIO_TYPE_PROXY_CLIENT;
-static const int BIO_TYPE_PROXY_SERVER;
 static const int BIO_TYPE_NBIO_TEST;
 static const int BIO_TYPE_BER;
 static const int BIO_TYPE_BIO;
diff --git a/src/_cffi_src/openssl/ec.py b/src/_cffi_src/openssl/ec.py
index 82476f18..91603096 100644
--- a/src/_cffi_src/openssl/ec.py
+++ b/src/_cffi_src/openssl/ec.py
@@ -76,8 +76,8 @@ int EC_KEY_get_flags(const EC_KEY *);
 void EC_KEY_set_flags(EC_KEY *, int);
 void EC_KEY_clear_flags(EC_KEY *, int);
 EC_KEY *EC_KEY_new_by_curve_name(int);
-EC_KEY *EC_KEY_copy(EC_KEY *, const EC_KEY *);
-EC_KEY *EC_KEY_dup(const EC_KEY *);
+EC_KEY *EC_KEY_copy(EC_KEY *, EC_KEY *);
+EC_KEY *EC_KEY_dup(EC_KEY *);
 int EC_KEY_up_ref(EC_KEY *);
 const EC_GROUP *EC_KEY_get0_group(const EC_KEY *);
 int EC_GROUP_get_order(const EC_GROUP *, BIGNUM *, BN_CTX *);
diff --git a/src/_cffi_src/openssl/ssl.py b/src/_cffi_src/openssl/ssl.py
index 32383871..75b0f130 100644
--- a/src/_cffi_src/openssl/ssl.py
+++ b/src/_cffi_src/openssl/ssl.py
@@ -399,7 +399,7 @@ void SSL_get0_next_proto_negotiated(const SSL *,
                                     const unsigned char **, unsigned *);
 
 int sk_SSL_CIPHER_num(Cryptography_STACK_OF_SSL_CIPHER *);
-SSL_CIPHER *sk_SSL_CIPHER_value(Cryptography_STACK_OF_SSL_CIPHER *, int);
+const SSL_CIPHER *sk_SSL_CIPHER_value(Cryptography_STACK_OF_SSL_CIPHER *, int);
 
 /* ALPN APIs were introduced in OpenSSL 1.0.2.  To continue to support earlier
  * versions some special handling of these is necessary.
diff --git a/src/cryptography/hazmat/backends/openssl/encode_asn1.py b/src/cryptography/hazmat/backends/openssl/encode_asn1.py
index 0ede533a..b0e2e73e 100644
--- a/src/cryptography/hazmat/backends/openssl/encode_asn1.py
+++ b/src/cryptography/hazmat/backends/openssl/encode_asn1.py
@@ -526,6 +526,23 @@ def _encode_name_constraints(backend, name_constraints):
     return nc
 
 
+def _encode_policy_constraints(backend, policy_constraints):
+    pc = backend._lib.POLICY_CONSTRAINTS_new()
+    backend.openssl_assert(pc != backend._ffi.NULL)
+    pc = backend._ffi.gc(pc, backend._lib.POLICY_CONSTRAINTS_free)
+    if policy_constraints.require_explicit_policy is not None:
+        pc.requireExplicitPolicy = _encode_asn1_int(
+            backend, policy_constraints.require_explicit_policy
+        )
+
+    if policy_constraints.inhibit_policy_mapping is not None:
+        pc.inhibitPolicyMapping = _encode_asn1_int(
+            backend, policy_constraints.inhibit_policy_mapping
+        )
+
+    return pc
+
+
 def _encode_general_subtree(backend, subtrees):
     if subtrees is None:
         return backend._ffi.NULL
@@ -556,6 +573,7 @@ _EXTENSION_ENCODE_HANDLERS = {
     ExtensionOID.INHIBIT_ANY_POLICY: _encode_inhibit_any_policy,
     ExtensionOID.OCSP_NO_CHECK: _encode_ocsp_nocheck,
     ExtensionOID.NAME_CONSTRAINTS: _encode_name_constraints,
+    ExtensionOID.POLICY_CONSTRAINTS: _encode_policy_constraints,
 }
 
 _CRL_EXTENSION_ENCODE_HANDLERS = {