diff --git a/src/OpenSSL.jl b/src/OpenSSL.jl
index fee43d6..d433987 100644
--- a/src/OpenSSL.jl
+++ b/src/OpenSSL.jl
@@ -8,6 +8,9 @@ include("consts.jl")
 include("evp_md.jl")
 include("types.jl")
 export SSLContext, SSLClient
+
+include("methods.jl")
+
 include("bio.jl")
 
 include("context.jl")
diff --git a/src/bio.jl b/src/bio.jl
index ec5a29f..68696cd 100644
--- a/src/bio.jl
+++ b/src/bio.jl
@@ -1,5 +1,21 @@
-s_mem() = ccall((:BIO_s_mem, libssl), Ptr{Cvoid}, ())
-bio_new(mem::Ptr{Cvoid}) = ccall((:BIO_new, libssl), Ptr{Cvoid}, (Ptr{Cvoid},), mem)
+# BIO_METHOD *   BIO_s_mem(void);
+
+# BIO_set_mem_eof_return(BIO *b,int v)
+# long BIO_get_mem_data(BIO *b, char **pp)
+# BIO_set_mem_buf(BIO *b,BUF_MEM *bm,int c)
+# BIO_get_mem_ptr(BIO *b,BUF_MEM **pp)
+
+# BIO *  BIO_new(const BIO_METHOD *type);
+# int    BIO_set(BIO *a, const BIO_METHOD *type);
+# # int    BIO_up_ref(BIO *a); # Don't see a use case
+# int    BIO_free(BIO *a);
+# # void   BIO_vfree(BIO *a);  # Same as BIO_free
+# void   BIO_free_all(BIO *a);
+
+s_mem() = ccall((:BIO_s_mem, libssl), Ptr{BIO_Method}, ())
+
+bio_new(mem::Ptr{BIO_Method}) =
+    ccall((:BIO_new, libssl), Ptr{Cvoid}, (Ptr{BIO_Method},), mem)
 bio_new() = bio_new(s_mem())
 
 function set_bio!(client::SSLClient, rbio, wbio)
diff --git a/src/certs.jl b/src/certs.jl
index 7407499..afe2407 100644
--- a/src/certs.jl
+++ b/src/certs.jl
@@ -18,6 +18,8 @@ end
 get_peer_certificate(client::SSLClient) =
     ccall((:SSL_get_peer_certificate, libssl), Ptr{Cvoid}, (Ptr{Cvoid},), client.ssl)
 
+# TODO: add response codes
+# https://www.openssl.org/docs/man1.0.2/man1/verify.html
 verify_certificate(client::SSLClient) =
     ccall((:SSL_get_verify_result, libssl), Clong, (Ptr{Cvoid},),
           client.ssl)
diff --git a/src/context.jl b/src/context.jl
index 8c19006..c4e7f2b 100644
--- a/src/context.jl
+++ b/src/context.jl
@@ -17,3 +17,8 @@ function set_verify_callback(ctx::SSLContext, callback)
     ccall((:SSL_CTX_set_cert_verify_callback, libssl), Cvoid,
           (Ptr{Cvoid}, Ptr{Cvoid}, Ptr{Cvoid}), ctx.ptr, callback, args)
 end
+
+free(ctx::SSLContext) = ccall((:SSL_CTX_free, libssl), Cvoid, (Ptr{Cvoid},), ctx.ptr)
+
+# TODO:
+# SSL_CTX_load_verify_locations
diff --git a/src/errors.jl b/src/errors.jl
new file mode 100644
index 0000000..5662fb9
--- /dev/null
+++ b/src/errors.jl
@@ -0,0 +1,7 @@
+# ERR_set_mark()
+# ERR_pop_to_mark()
+
+ERR_pop_to_mark() = ccall((:ERR_pop_to_mark, libssl), Cint, ())
+ERR_set_mark() = ccall((:ERR_set_mark, libssl), Cint, ())
+ERR_print_errors(file_ptr) =
+    ccall((:ERR_print_errors, libssl), Cvoid, (Ptr{Cvoid},), file_ptr)
diff --git a/src/methods.jl b/src/methods.jl
new file mode 100644
index 0000000..63407c8
--- /dev/null
+++ b/src/methods.jl
@@ -0,0 +1,29 @@
+# https://www.openssl.org/docs/man1.1.0/man3/TLS_server_method.html
+TLSv1_2_method() = ccall((:TLSv1_2_method, libssl), Ptr{SSL_Method}, ())
+TLSv1_2_server_method() = ccall((:TLSv1_2_server_method, libssl), Ptr{SSL_Method}, ())
+TLSv1_2_client_method() = ccall((:TLSv1_2_client_method, libssl), Ptr{SSL_Method}, ())
+# Not defined in my openssl release
+# SSLv3_method() = ccall((:SSLv3_method, libssl), Ptr{SSL_Method}, ())
+# SSLv3_server_method() = ccall((:SSLv3_server_method, libssl), Ptr{SSL_Method}, ())
+# SSLv3_client_method() = ccall((:SSLv3_client_method, libssl), Ptr{SSL_Method}, ())
+TLSv1_method() = ccall((:TLSv1_method, libssl), Ptr{SSL_Method}, ())
+TLSv1_server_method() = ccall((:TLSv1_server_method, libssl), Ptr{SSL_Method}, ())
+TLSv1_client_method() = ccall((:TLSv1_client_method, libssl), Ptr{SSL_Method}, ())
+TLSv1_1_method() = ccall((:TLSv1_1_method, libssl), Ptr{SSL_Method}, ())
+TLSv1_1_server_method() = ccall((:TLSv1_1_server_method, libssl), Ptr{SSL_Method}, ())
+TLSv1_1_client_method() = ccall((:TLSv1_1_client_method, libssl), Ptr{SSL_Method}, ())
+TLS_method() = ccall((:TLS_method, libssl), Ptr{SSL_Method}, ())
+TLS_server_method() = ccall((:TLS_server_method, libssl), Ptr{SSL_Method}, ())
+TLS_client_method() = ccall((:TLS_client_method, libssl), Ptr{SSL_Method}, ())
+SSLv23_method() = ccall((:SSLv23_method, libssl), Ptr{SSL_Method}, ())
+SSLv23_server_method() = ccall((:SSLv23_server_method, libssl), Ptr{SSL_Method}, ())
+SSLv23_client_method() = ccall((:SSLv23_client_method, libssl), Ptr{SSL_Method}, ())
+DTLS_method() = ccall((:DTLS_method, libssl), Ptr{SSL_Method}, ())
+DTLS_server_method() = ccall((:DTLS_server_method, libssl), Ptr{SSL_Method}, ())
+DTLS_client_method() = ccall((:DTLS_client_method, libssl), Ptr{SSL_Method}, ())
+DTLSv1_method() = ccall((:DTLSv1_method, libssl), Ptr{SSL_Method}, ())
+DTLSv1_server_method() = ccall((:DTLSv1_server_method, libssl), Ptr{SSL_Method}, ())
+DTLSv1_client_method() = ccall((:DTLSv1_client_method, libssl), Ptr{SSL_Method}, ())
+DTLSv1_2_method() = ccall((:DTLSv1_2_method, libssl), Ptr{SSL_Method}, ())
+DTLSv1_2_server_method() = ccall((:DTLSv1_2_server_method, libssl), Ptr{SSL_Method}, ())
+DTLSv1_2_client_method() = ccall((:DTLSv1_2_client_method, libssl), Ptr{SSL_Method}, ())
diff --git a/src/ssl.jl b/src/ssl.jl
index 23801ab..7bd3a6c 100644
--- a/src/ssl.jl
+++ b/src/ssl.jl
@@ -7,6 +7,9 @@ SSL_handshake(client::SSLClient) =
 SSL_new(ctx::SSLContext) =
     ccall((:SSL_new, libssl), Ptr{Cvoid}, (Ptr{Cvoid},), ctx.ptr)
 
+SSL_CTX_new(method::Ptr{SSL_Method}) =
+    ccall((:SSL_CTX_new, libssl), Ptr{SSL_Context}, (Ptr{SSL_Method},), method)
+
 SSL_accept_state(client::SSLClient) =
     ccall((:SSL_set_accept_state, libssl), Ptr{Cvoid}, (Ptr{Cvoid},), client.ssl)
 
@@ -30,5 +33,4 @@ ssl_write(client::SSLClient, buf::Vector{UInt8}) =
 shutdown(client::SSLClient) =
     ccall((:SSL_shutdown, libssl), Cint, (Ptr{Cvoid},), client.ssl)
 
-free(client::SSLClient) =
-    ccall((:SSL_free, libssl), Cint, (Ptr{Cvoid},), client.ssl)
+free(client::SSLClient) = ccall((:SSL_free, libssl), Cint, (Ptr{Cvoid},), client.ssl)
diff --git a/src/types.jl b/src/types.jl
index 07f5e2e..9503c2d 100644
--- a/src/types.jl
+++ b/src/types.jl
@@ -1,13 +1,23 @@
+# Returned from C as Ptr
+struct SSL_Method ptr end
+struct BIO_Method ptr end
+struct SSL_Context ptr end
+
 mutable struct SSLContext <: IO
     data
-    ptr::Ptr{Cvoid}
+    ptr::Ptr{SSL_Context}
 
-    function SSLContext()
+    "Construct the SSLContext object, initializing its relatvie SSL_Context
+    pointer.
+
+    Might throw ErrorException if the ccall fails"
+    function SSLContext(; method::Ptr{SSL_Method} = TLS_method())
         ssl_context = new()
-	method = ccall((:TLS_server_method, libssl), Ptr{Cvoid}, ())
-	ssl_context.ptr = ccall((:SSL_CTX_new, libssl), Ptr{Cvoid}, (Ptr{Cvoid},), method)
-	# if ssl_context.ptr == 0
-	# end
+	ssl_context.ptr = SSL_CTX_new(method)
+	if ssl_context.ptr == C_NULL
+            # TODO: check error stack and report the right exception
+            throw(ErrorException("Could not create SSL context"))
+	end
 	ssl_context
     end
 end
@@ -32,6 +42,7 @@ mutable struct SSLClient{T}
         client.write_buf = UInt8[]
         client.encrypt_buf = UInt8[]
         client.sock = io
+        # finalizer(free, client)
         client
     end
 end