r1294: A nice, large, commit...

This implements gensec for Samba's server side, and brings gensec up
to the standards of a full subsystem.

This means that use of the subsystem is by gensec_* functions, not
function pointers in structures (this is internal).  This causes
changes in all the existing gensec users.

Our RPC server no longer contains it's own generalised security
scheme, and now calls gensec directly.

Gensec has also taken over the role of auth/auth_ntlmssp.c

An important part of gensec, is the output of the 'session_info'
struct.  This is now reference counted, so that we can correctly free
it when a pipe is closed, no matter if it was inherited, or created by
per-pipe authentication.

The schannel code is reworked, to be in the same file for client and
server.

ntlm_auth is reworked to use gensec.

The major problem with this code is the way it relies on subsystem
auto-initialisation.  The primary reason for this commit now.is to
allow these problems to be looked at, and fixed.

There are problems with the new code:
- I've tested it with smbtorture, but currently don't have VMware and
  valgrind working (this I'll fix soon).
- The SPNEGO code is client-only at this point.
- We still do not do kerberos.

Andrew Bartlett
(This used to be commit 07fd885fd488fd1051eacc905a2d4962f8a018ec)

1 files changed, 362 insertions, 43 deletions

diff --git a/source4/libcli/auth/gensec.c b/source4/libcli/auth/gensec.c
index 138c4af35c..f6d6db9e62 100644
--- a/source4/libcli/auth/gensec.c
+++ b/source4/libcli/auth/gensec.c
@@ -23,46 +23,14 @@
 
 #include "includes.h"
 
-static const struct gensec_security_ops gensec_ntlmssp_security_ops = {
-	.name		= "ntlmssp",
-	.sasl_name	= "NTLM",
-	.auth_type	= DCERPC_AUTH_TYPE_NTLMSSP,
-	.oid            = OID_NTLMSSP,
-	.client_start   = gensec_ntlmssp_client_start,
-	.update 	= gensec_ntlmssp_update,
-	.seal 		= gensec_ntlmssp_seal_packet,
-	.sign		= gensec_ntlmssp_sign_packet,
-	.check_sig	= gensec_ntlmssp_check_packet,
-	.unseal		= gensec_ntlmssp_unseal_packet,
-	.session_key	= gensec_ntlmssp_session_key,
-	.end		= gensec_ntlmssp_end
-};
-
-
-static const struct gensec_security_ops gensec_spnego_security_ops = {
-	.name		= "spnego",
-	.sasl_name	= "GSS-SPNEGO",
-	.oid            = OID_SPNEGO,
-	.client_start   = gensec_spnego_client_start,
-	.update 	= gensec_spnego_update,
-	.seal 		= gensec_spnego_seal_packet,
-	.sign		= gensec_spnego_sign_packet,
-	.check_sig	= gensec_spnego_check_packet,
-	.unseal		= gensec_spnego_unseal_packet,
-	.session_key	= gensec_spnego_session_key,
-	.end		= gensec_spnego_end
-};
-
-static const struct gensec_security_ops *generic_security_ops[] = {
-	&gensec_ntlmssp_security_ops,
-	&gensec_spnego_security_ops,
-	NULL
-};
-
-const struct gensec_security_ops *gensec_security_by_authtype(uint8_t auth_type)
+/* the list of currently registered GENSEC backends */
+const static struct gensec_security_ops **generic_security_ops;
+static int num_backends;
+
+static const struct gensec_security_ops *gensec_security_by_authtype(uint8_t auth_type)
 {
 	int i;
-	for (i=0; generic_security_ops[i]; i++) {
+	for (i=0; i < num_backends; i++) {
 		if (generic_security_ops[i]->auth_type == auth_type) {
 			return generic_security_ops[i];
 		}
@@ -71,10 +39,10 @@ const struct gensec_security_ops *gensec_security_by_authtype(uint8_t auth_type)
 	return NULL;
 }
 
-const struct gensec_security_ops *gensec_security_by_oid(const char *oid)
+static const struct gensec_security_ops *gensec_security_by_oid(const char *oid)
 {
 	int i;
-	for (i=0; generic_security_ops[i]; i++) {
+	for (i=0; i < num_backends; i++) {
 		if (generic_security_ops[i]->oid &&
 		    (strcmp(generic_security_ops[i]->oid, oid) == 0)) {
 			return generic_security_ops[i];
@@ -84,10 +52,10 @@ const struct gensec_security_ops *gensec_security_by_oid(const char *oid)
 	return NULL;
 }
 
-const struct gensec_security_ops *gensec_security_by_sasl_name(const char *sasl_name)
+static const struct gensec_security_ops *gensec_security_by_sasl_name(const char *sasl_name)
 {
 	int i;
-	for (i=0; generic_security_ops[i]; i++) {
+	for (i=0; i < num_backends; i++) {
 		if (generic_security_ops[i]->sasl_name 
 		    && (strcmp(generic_security_ops[i]->sasl_name, sasl_name) == 0)) {
 			return generic_security_ops[i];
@@ -97,8 +65,359 @@ const struct gensec_security_ops *gensec_security_by_sasl_name(const char *sasl_
 	return NULL;
 }
 
-const struct gensec_security_ops **gensec_security_all(void)
+static const struct gensec_security_ops *gensec_security_by_name(const char *name)
+{
+	int i;
+	for (i=0; i < num_backends; i++) {
+		if (generic_security_ops[i]->name 
+		    && (strcmp(generic_security_ops[i]->name, name) == 0)) {
+			return generic_security_ops[i];
+		}
+	}
+
+	return NULL;
+}
+
+const struct gensec_security_ops **gensec_security_all(int *num_backends_out)
 {
+	*num_backends_out = num_backends;
 	return generic_security_ops;
 }
 
+static NTSTATUS gensec_start(struct gensec_security **gensec_security) 
+{
+	TALLOC_CTX *mem_ctx;
+	/* awaiting a correct fix from metze */
+	if (!gensec_init()) {
+		return NT_STATUS_INTERNAL_ERROR;
+	}
+
+	mem_ctx = talloc_init("gensec_security struct");
+	if (!mem_ctx) {
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	(*gensec_security) = talloc_p(mem_ctx, struct gensec_security);
+	if (!(*gensec_security)) {
+		talloc_destroy(mem_ctx);
+		return NT_STATUS_NO_MEMORY;
+	}
+
+	(*gensec_security)->mem_ctx = mem_ctx;
+	(*gensec_security)->ops = NULL;
+
+	return NT_STATUS_OK;
+}
+
+NTSTATUS gensec_client_start(struct gensec_security **gensec_security)
+{
+	NTSTATUS status;
+	status = gensec_start(gensec_security);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+	(*gensec_security)->gensec_role = GENSEC_CLIENT;
+	(*gensec_security)->password_callback = NULL;
+
+	ZERO_STRUCT((*gensec_security)->user);
+
+	return status;
+}
+
+NTSTATUS gensec_server_start(struct gensec_security **gensec_security)
+{
+	NTSTATUS status;
+	status = gensec_start(gensec_security);
+	if (!NT_STATUS_IS_OK(status)) {
+		return status;
+	}
+	(*gensec_security)->gensec_role = GENSEC_SERVER;
+
+	return status;
+}
+
+static NTSTATUS gensec_start_mech(struct gensec_security *gensec_security) 
+{
+	NTSTATUS status;
+	switch (gensec_security->gensec_role) {
+	case GENSEC_CLIENT:
+		if (gensec_security->ops->client_start) {
+			status = gensec_security->ops->client_start(gensec_security);
+			if (!NT_STATUS_IS_OK(status)) {
+				DEBUG(1, ("Faild to start GENSEC client mech %s: %s\n",
+					  gensec_security->ops->name, nt_errstr(status))); 
+			}
+			return status;
+		}
+	case GENSEC_SERVER:
+		if (gensec_security->ops->server_start) {
+			status = gensec_security->ops->server_start(gensec_security);
+			if (!NT_STATUS_IS_OK(status)) {
+				DEBUG(1, ("Faild to start GENSEC server mech %s: %s\n",
+					  gensec_security->ops->name, nt_errstr(status))); 
+			}
+			return status;
+		}
+	}
+	return NT_STATUS_INVALID_PARAMETER;
+}
+
+NTSTATUS gensec_start_mech_by_authtype(struct gensec_security *gensec_security, 
+				       uint8_t authtype) 
+{
+	gensec_security->ops = gensec_security_by_authtype(authtype);
+	if (!gensec_security->ops) {
+		DEBUG(1, ("Could not find GENSEC backend for authtype=%d\n", (int)authtype));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+	return gensec_start_mech(gensec_security);
+}
+
+NTSTATUS gensec_start_mech_by_oid(struct gensec_security *gensec_security, 
+				  const char *mech_oid) 
+{
+	gensec_security->ops = gensec_security_by_oid(mech_oid);
+	if (!gensec_security->ops) {
+		DEBUG(1, ("Could not find GENSEC backend for oid=%s\n", mech_oid));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+	return gensec_start_mech(gensec_security);
+}
+
+NTSTATUS gensec_start_mech_by_sasl_name(struct gensec_security *gensec_security, 
+					const char *sasl_name) 
+{
+	gensec_security->ops = gensec_security_by_sasl_name(sasl_name);
+	if (!gensec_security->ops) {
+		DEBUG(1, ("Could not find GENSEC backend for sasl_name=%s\n", sasl_name));
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+	return gensec_start_mech(gensec_security);
+}
+
+/*
+  wrappers for the gensec function pointers
+*/
+NTSTATUS gensec_unseal_packet(struct gensec_security *gensec_security, 
+			      TALLOC_CTX *mem_ctx, 
+			      uint8_t *data, size_t length, DATA_BLOB *sig)
+{
+	return gensec_security->ops->unseal_packet(gensec_security, mem_ctx, data, length, sig);
+}
+
+NTSTATUS gensec_check_packet(struct gensec_security *gensec_security, 
+			     TALLOC_CTX *mem_ctx, 
+			     const uint8_t *data, size_t length, 
+			     const DATA_BLOB *sig)
+{
+	return gensec_security->ops->check_packet(gensec_security, mem_ctx, data, length, sig);
+}
+
+NTSTATUS gensec_seal_packet(struct gensec_security *gensec_security, 
+			    TALLOC_CTX *mem_ctx, 
+			    uint8_t *data, size_t length, 
+			    DATA_BLOB *sig)
+{
+	return gensec_security->ops->seal_packet(gensec_security, mem_ctx, data, length, sig);
+}
+
+NTSTATUS gensec_sign_packet(struct gensec_security *gensec_security, 
+			    TALLOC_CTX *mem_ctx, 
+			    const uint8_t *data, size_t length, 
+			    DATA_BLOB *sig)
+{
+	return gensec_security->ops->sign_packet(gensec_security, mem_ctx, data, length, sig);
+}
+
+NTSTATUS gensec_session_key(struct gensec_security *gensec_security, 
+			    DATA_BLOB *session_key)
+{
+	return gensec_security->ops->session_key(gensec_security, session_key);
+}
+
+NTSTATUS gensec_session_info(struct gensec_security *gensec_security, 
+			     struct auth_session_info **session_info)
+{
+	return gensec_security->ops->session_info(gensec_security, session_info);
+}
+
+/**
+ * Next state function for the GENSEC state machine
+ * 
+ * @param gensec_security GENSEC State
+ * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
+ * @param in The request, as a DATA_BLOB
+ * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
+ * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent, 
+ *                or NT_STATUS_OK if the user is authenticated. 
+ */
+
+NTSTATUS gensec_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx, 
+		       const DATA_BLOB in, DATA_BLOB *out) 
+{
+	return gensec_security->ops->update(gensec_security, out_mem_ctx, in, out);
+}
+
+void gensec_end(struct gensec_security **gensec_security)
+{
+	if ((*gensec_security)->ops) {
+		(*gensec_security)->ops->end(*gensec_security);
+	}
+	(*gensec_security)->private_data = NULL;
+	talloc_destroy((*gensec_security)->mem_ctx);
+	
+	gensec_security = NULL;
+}
+
+/** 
+ * Set a username on a GENSEC context - ensures it is talloc()ed 
+ *
+ */
+
+NTSTATUS gensec_set_username(struct gensec_security *gensec_security, const char *user) 
+{
+	gensec_security->user.name = talloc_strdup(gensec_security->mem_ctx, user);
+	if (!gensec_security->user.name) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	return NT_STATUS_OK;
+}
+
+/** 
+ * Set a domain on a GENSEC context - ensures it is talloc()ed 
+ *
+ */
+
+NTSTATUS gensec_set_domain(struct gensec_security *gensec_security, const char *domain) 
+{
+	gensec_security->user.domain = talloc_strdup(gensec_security->mem_ctx, domain);
+	if (!gensec_security->user.domain) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	return NT_STATUS_OK;
+}
+
+/** 
+ * Set the password outright on GENSEC context - ensures it is talloc()ed, and that we will
+ * not do a callback
+ *
+ */
+
+NTSTATUS gensec_set_password(struct gensec_security *gensec_security,
+			     const char *password) 
+{
+	gensec_security->user.password = talloc_strdup(gensec_security->mem_ctx, password);
+	if (!gensec_security->user.password) {
+		return NT_STATUS_NO_MEMORY;
+	}
+	return NT_STATUS_OK;
+}
+
+/** 
+ * Set a password callback, if the gensec module we use demands a password
+ */
+
+void gensec_set_password_callback(struct gensec_security *gensec_security, 
+				  gensec_password_callback callback, void *callback_private_data) 
+{
+	gensec_security->password_callback = callback;
+	gensec_security->password_callback_private = callback_private_data;
+}
+
+/**
+ * Get (or call back for) a password.
+ */
+
+NTSTATUS gensec_get_password(struct gensec_security *gensec_security,
+			     TALLOC_CTX *mem_ctx, 
+			     char **password) 
+{
+	if (gensec_security->user.password) {
+		*password = talloc_strdup(mem_ctx, gensec_security->user.password);
+		if (!*password) {
+			return NT_STATUS_NO_MEMORY;
+		} else {
+			return NT_STATUS_OK;
+		}
+	}
+	if (!gensec_security->password_callback) {
+		return NT_STATUS_INVALID_PARAMETER;
+	}
+	return gensec_security->password_callback(gensec_security, mem_ctx, password);
+}
+
+/*
+  register a GENSEC backend. 
+
+  The 'name' can be later used by other backends to find the operations
+  structure for this backend.
+*/
+static NTSTATUS gensec_register(const void *_ops)
+{
+	const struct gensec_security_ops *ops = _ops;
+	
+	if (gensec_security_by_name(ops->name) != NULL) {
+		/* its already registered! */
+		DEBUG(0,("GENSEC backend '%s' already registered\n", 
+			 ops->name));
+		return NT_STATUS_OBJECT_NAME_COLLISION;
+	}
+
+	generic_security_ops = Realloc(generic_security_ops, sizeof(generic_security_ops[0]) * (num_backends+1));
+	if (!generic_security_ops) {
+		smb_panic("out of memory in gensec_register");
+	}
+
+	generic_security_ops[num_backends] = ops;
+
+	num_backends++;
+
+	DEBUG(3,("GENSEC backend '%s' registered\n", 
+		 ops->name));
+
+	return NT_STATUS_OK;
+}
+
+/*
+  return the GENSEC interface version, and the size of some critical types
+  This can be used by backends to either detect compilation errors, or provide
+  multiple implementations for different smbd compilation options in one module
+*/
+const struct gensec_critical_sizes *gensec_interface_version(void)
+{
+	static const struct gensec_critical_sizes critical_sizes = {
+		GENSEC_INTERFACE_VERSION,
+		sizeof(struct gensec_security_ops),
+		sizeof(struct gensec_security),
+	};
+
+	return &critical_sizes;
+}
+
+/*
+  initialise the GENSEC subsystem
+*/
+BOOL gensec_init(void)
+{
+	static BOOL initialised;
+	NTSTATUS status;
+
+	/* this is *completly* the wrong way to do this */
+	if (initialised) {
+		return True;
+	}
+
+	status = register_subsystem("gensec", gensec_register); 
+	if (!NT_STATUS_IS_OK(status)) {
+		return False;
+	}
+
+	/* FIXME: Perhaps panic if a basic backend, such as NTLMSSP, fails to initialise? */
+	gensec_ntlmssp_init();
+	gensec_spengo_init();
+	gensec_dcerpc_schannel_init();
+
+	initialised = True;
+	DEBUG(3,("GENSEC subsystem version %d initialised\n", GENSEC_INTERFACE_VERSION));
+	return True;
+}