Initial import
[samba] / source / auth / auth.c
diff --git a/source/auth/auth.c b/source/auth/auth.c
new file mode 100644 (file)
index 0000000..df7d6fc
--- /dev/null
@@ -0,0 +1,539 @@
+/* 
+   Unix SMB/CIFS implementation.
+   Password and authentication handling
+   Copyright (C) Andrew Bartlett         2001-2002
+   
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+   
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+   
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_AUTH
+
+static struct auth_init_function_entry *backends = NULL;
+
+static struct auth_init_function_entry *auth_find_backend_entry(const char *name);
+
+NTSTATUS smb_register_auth(int version, const char *name, auth_init_function init)
+{
+       struct auth_init_function_entry *entry = backends;
+
+       if (version != AUTH_INTERFACE_VERSION) {
+               DEBUG(0,("Can't register auth_method!\n"
+                        "You tried to register an auth module with AUTH_INTERFACE_VERSION %d, while this version of samba uses %d\n",
+                        version,AUTH_INTERFACE_VERSION));
+               return NT_STATUS_OBJECT_TYPE_MISMATCH;
+       }
+
+       if (!name || !init) {
+               return NT_STATUS_INVALID_PARAMETER;
+       }
+
+       DEBUG(5,("Attempting to register auth backend %s\n", name));
+
+       if (auth_find_backend_entry(name)) {
+               DEBUG(0,("There already is an auth method registered with the name %s!\n", name));
+               return NT_STATUS_OBJECT_NAME_COLLISION;
+       }
+       
+       entry = SMB_XMALLOC_P(struct auth_init_function_entry);
+       entry->name = smb_xstrdup(name);
+       entry->init = init;
+
+       DLIST_ADD(backends, entry);
+       DEBUG(5,("Successfully added auth method '%s'\n", name));
+       return NT_STATUS_OK;
+}
+
+static struct auth_init_function_entry *auth_find_backend_entry(const char *name)
+{
+       struct auth_init_function_entry *entry = backends;
+
+       while(entry) {
+               if (strcmp(entry->name, name)==0) return entry;
+               entry = entry->next;
+       }
+       
+       return NULL;
+}
+
+/****************************************************************************
+ Try to get a challenge out of the various authentication modules.
+ Returns a const char of length 8 bytes.
+****************************************************************************/
+
+static const uint8 *get_ntlm_challenge(struct auth_context *auth_context) 
+{
+       DATA_BLOB challenge = data_blob(NULL, 0);
+       const char *challenge_set_by = NULL;
+       auth_methods *auth_method;
+       TALLOC_CTX *mem_ctx;
+
+       if (auth_context->challenge.length) {
+               DEBUG(5, ("get_ntlm_challenge (auth subsystem): returning previous challenge by module %s (normal)\n", 
+                         auth_context->challenge_set_by));
+               return auth_context->challenge.data;
+       }
+
+       auth_context->challenge_may_be_modified = False;
+
+       for (auth_method = auth_context->auth_method_list; auth_method; auth_method = auth_method->next) {
+               if (auth_method->get_chal == NULL) {
+                       DEBUG(5, ("auth_get_challenge: module %s did not want to specify a challenge\n", auth_method->name));
+                       continue;
+               }
+
+               DEBUG(5, ("auth_get_challenge: getting challenge from module %s\n", auth_method->name));
+               if (challenge_set_by != NULL) {
+                       DEBUG(1, ("auth_get_challenge: CONFIGURATION ERROR: authentication method %s has already specified a challenge.  Challenge by %s ignored.\n", 
+                                 challenge_set_by, auth_method->name));
+                       continue;
+               }
+
+               mem_ctx = talloc_init("auth_get_challenge for module %s", auth_method->name);
+               if (!mem_ctx) {
+                       smb_panic("talloc_init() failed!");
+               }
+               
+               challenge = auth_method->get_chal(auth_context, &auth_method->private_data, mem_ctx);
+               if (!challenge.length) {
+                       DEBUG(3, ("auth_get_challenge: getting challenge from authentication method %s FAILED.\n", 
+                                 auth_method->name));
+               } else {
+                       DEBUG(5, ("auth_get_challenge: sucessfully got challenge from module %s\n", auth_method->name));
+                       auth_context->challenge = challenge;
+                       challenge_set_by = auth_method->name;
+                       auth_context->challenge_set_method = auth_method;
+               }
+               talloc_destroy(mem_ctx);
+       }
+       
+       if (!challenge_set_by) {
+               uchar chal[8];
+               
+               generate_random_buffer(chal, sizeof(chal));
+               auth_context->challenge = data_blob_talloc(auth_context->mem_ctx, 
+                                                          chal, sizeof(chal));
+               
+               challenge_set_by = "random";
+               auth_context->challenge_may_be_modified = True;
+       } 
+       
+       DEBUG(5, ("auth_context challenge created by %s\n", challenge_set_by));
+       DEBUG(5, ("challenge is: \n"));
+       dump_data(5, (const char *)auth_context->challenge.data, auth_context->challenge.length);
+       
+       SMB_ASSERT(auth_context->challenge.length == 8);
+
+       auth_context->challenge_set_by=challenge_set_by;
+
+       return auth_context->challenge.data;
+}
+
+
+/**
+ * Check user is in correct domain (if required)
+ *
+ * @param user Only used to fill in the debug message
+ * 
+ * @param domain The domain to be verified
+ *
+ * @return True if the user can connect with that domain, 
+ *         False otherwise.
+**/
+
+static BOOL check_domain_match(const char *user, const char *domain) 
+{
+       /*
+        * If we aren't serving to trusted domains, we must make sure that
+        * the validation request comes from an account in the same domain
+        * as the Samba server
+        */
+
+       if (!lp_allow_trusted_domains() &&
+           !(strequal("", domain) || 
+             strequal(lp_workgroup(), domain) || 
+             is_myname(domain))) {
+               DEBUG(1, ("check_domain_match: Attempt to connect as user %s from domain %s denied.\n", user, domain));
+               return False;
+       } else {
+               return True;
+       }
+}
+
+/**
+ * Check a user's Plaintext, LM or NTLM password.
+ *
+ * Check a user's password, as given in the user_info struct and return various
+ * interesting details in the server_info struct.
+ *
+ * This function does NOT need to be in a become_root()/unbecome_root() pair
+ * as it makes the calls itself when needed.
+ *
+ * The return value takes precedence over the contents of the server_info 
+ * struct.  When the return is other than NT_STATUS_OK the contents 
+ * of that structure is undefined.
+ *
+ * @param user_info Contains the user supplied components, including the passwords.
+ *                  Must be created with make_user_info() or one of its wrappers.
+ *
+ * @param auth_context Supplies the challenges and some other data. 
+ *                  Must be created with make_auth_context(), and the challenges should be 
+ *                  filled in, either at creation or by calling the challenge geneation 
+ *                  function auth_get_challenge().  
+ *
+ * @param server_info If successful, contains information about the authentication, 
+ *                    including a SAM_ACCOUNT struct describing the user.
+ *
+ * @return An NTSTATUS with NT_STATUS_OK or an appropriate error.
+ *
+ **/
+
+static NTSTATUS check_ntlm_password(const struct auth_context *auth_context,
+                                   const struct auth_usersupplied_info *user_info, 
+                                   struct auth_serversupplied_info **server_info)
+{
+       /* if all the modules say 'not for me' this is reasonable */
+       NTSTATUS nt_status = NT_STATUS_NO_SUCH_USER;
+       const char *unix_username;
+       auth_methods *auth_method;
+       TALLOC_CTX *mem_ctx;
+
+       if (!user_info || !auth_context || !server_info)
+               return NT_STATUS_LOGON_FAILURE;
+
+       DEBUG(3, ("check_ntlm_password:  Checking password for unmapped user [%s]\\[%s]@[%s] with the new password interface\n", 
+                 user_info->client_domain.str, user_info->smb_name.str, user_info->wksta_name.str));
+
+       DEBUG(3, ("check_ntlm_password:  mapped user is: [%s]\\[%s]@[%s]\n", 
+                 user_info->domain.str, user_info->internal_username.str, user_info->wksta_name.str));
+
+       if (auth_context->challenge.length != 8) {
+               DEBUG(0, ("check_ntlm_password:  Invalid challenge stored for this auth context - cannot continue\n"));
+               return NT_STATUS_LOGON_FAILURE;
+       }
+
+       if (auth_context->challenge_set_by)
+               DEBUG(10, ("check_ntlm_password: auth_context challenge created by %s\n",
+                                       auth_context->challenge_set_by));
+
+       DEBUG(10, ("challenge is: \n"));
+       dump_data(5, (const char *)auth_context->challenge.data, auth_context->challenge.length);
+
+#ifdef DEBUG_PASSWORD
+       DEBUG(100, ("user_info has passwords of length %d and %d\n", 
+                   (int)user_info->lm_resp.length, (int)user_info->nt_resp.length));
+       DEBUG(100, ("lm:\n"));
+       dump_data(100, (const char *)user_info->lm_resp.data, user_info->lm_resp.length);
+       DEBUG(100, ("nt:\n"));
+       dump_data(100, (const char *)user_info->nt_resp.data, user_info->nt_resp.length);
+#endif
+
+       /* This needs to be sorted:  If it doesn't match, what should we do? */
+       if (!check_domain_match(user_info->smb_name.str, user_info->domain.str))
+               return NT_STATUS_LOGON_FAILURE;
+
+       for (auth_method = auth_context->auth_method_list;auth_method; auth_method = auth_method->next) {
+               NTSTATUS result;
+               
+               mem_ctx = talloc_init("%s authentication for user %s\\%s", auth_method->name, 
+                                           user_info->domain.str, user_info->smb_name.str);
+
+               result = auth_method->auth(auth_context, auth_method->private_data, mem_ctx, user_info, server_info);
+
+               /* check if the module did anything */
+               if ( NT_STATUS_V(result) == NT_STATUS_V(NT_STATUS_NOT_IMPLEMENTED) ) {
+                       DEBUG(10,("check_ntlm_password: %s had nothing to say\n", auth_method->name));
+                       talloc_destroy(mem_ctx);
+                       continue;
+               }
+
+               nt_status = result;
+
+               if (NT_STATUS_IS_OK(nt_status)) {
+                       DEBUG(3, ("check_ntlm_password: %s authentication for user [%s] succeeded\n", 
+                                 auth_method->name, user_info->smb_name.str));
+               } else {
+                       DEBUG(5, ("check_ntlm_password: %s authentication for user [%s] FAILED with error %s\n", 
+                                 auth_method->name, user_info->smb_name.str, nt_errstr(nt_status)));
+               }
+
+               talloc_destroy(mem_ctx);
+
+               if ( NT_STATUS_IS_OK(nt_status))
+               {
+                               break;                  
+               }
+       }
+
+       /* successful authentication */
+       
+       if (NT_STATUS_IS_OK(nt_status)) {
+               unix_username = (*server_info)->unix_name;
+               if (!(*server_info)->guest) {
+                       /* We might not be root if we are an RPC call */
+                       become_root();
+                       nt_status = smb_pam_accountcheck(unix_username);
+                       unbecome_root();
+                       
+                       if (NT_STATUS_IS_OK(nt_status)) {
+                               DEBUG(5, ("check_ntlm_password:  PAM Account for user [%s] succeeded\n", 
+                                         unix_username));
+                       } else {
+                               DEBUG(3, ("check_ntlm_password:  PAM Account for user [%s] FAILED with error %s\n", 
+                                         unix_username, nt_errstr(nt_status)));
+                       } 
+               }
+               
+               if (NT_STATUS_IS_OK(nt_status)) {
+                       DEBUG((*server_info)->guest ? 5 : 2, 
+                             ("check_ntlm_password:  %sauthentication for user [%s] -> [%s] -> [%s] succeeded\n", 
+                              (*server_info)->guest ? "guest " : "", 
+                              user_info->smb_name.str, 
+                              user_info->internal_username.str, 
+                              unix_username));
+               }
+               
+               return nt_status;
+       }
+       
+       /* failed authentication; check for guest lapping */
+       
+       DEBUG(2, ("check_ntlm_password:  Authentication for user [%s] -> [%s] FAILED with error %s\n", 
+       user_info->smb_name.str, user_info->internal_username.str, 
+       nt_errstr(nt_status)));
+       ZERO_STRUCTP(server_info); 
+       
+       return nt_status;
+}
+
+/***************************************************************************
+ Clear out a auth_context, and destroy the attached TALLOC_CTX
+***************************************************************************/
+
+static void free_auth_context(struct auth_context **auth_context)
+{
+       auth_methods *auth_method;
+
+       if (*auth_context) {
+               /* Free private data of context's authentication methods */
+               for (auth_method = (*auth_context)->auth_method_list; auth_method; auth_method = auth_method->next) {
+                       if (auth_method->free_private_data) {
+                               auth_method->free_private_data (&auth_method->private_data);
+                               auth_method->private_data = NULL;
+                       }
+               }
+
+               talloc_destroy((*auth_context)->mem_ctx);
+               *auth_context = NULL;
+       }
+}
+
+/***************************************************************************
+ Make a auth_info struct
+***************************************************************************/
+
+static NTSTATUS make_auth_context(struct auth_context **auth_context) 
+{
+       TALLOC_CTX *mem_ctx;
+
+       mem_ctx = talloc_init("authentication context");
+       
+       *auth_context = TALLOC_P(mem_ctx, struct auth_context);
+       if (!*auth_context) {
+               DEBUG(0,("make_auth_context: talloc failed!\n"));
+               talloc_destroy(mem_ctx);
+               return NT_STATUS_NO_MEMORY;
+       }
+       ZERO_STRUCTP(*auth_context);
+
+       (*auth_context)->mem_ctx = mem_ctx;
+       (*auth_context)->check_ntlm_password = check_ntlm_password;
+       (*auth_context)->get_ntlm_challenge = get_ntlm_challenge;
+       (*auth_context)->free = free_auth_context;
+       
+       return NT_STATUS_OK;
+}
+
+BOOL load_auth_module(struct auth_context *auth_context, 
+                     const char *module, auth_methods **ret) 
+{
+       static BOOL initialised_static_modules = False;
+
+       struct auth_init_function_entry *entry;
+       char *module_name = smb_xstrdup(module);
+       char *module_params = NULL;
+       char *p;
+       BOOL good = False;
+
+       /* Initialise static modules if not done so yet */
+       if(!initialised_static_modules) {
+               static_init_auth;
+               initialised_static_modules = True;
+       }
+       
+       DEBUG(5,("load_auth_module: Attempting to find an auth method to match %s\n",
+                module));
+       
+       p = strchr(module_name, ':');
+       if (p) {
+               *p = 0;
+               module_params = p+1;
+               trim_char(module_params, ' ', ' ');
+       }
+       
+       trim_char(module_name, ' ', ' ');
+       
+       entry = auth_find_backend_entry(module_name);
+       
+       if (entry == NULL) {
+               if (NT_STATUS_IS_OK(smb_probe_module("auth", module_name))) {
+                       entry = auth_find_backend_entry(module_name);
+               }
+       }
+
+       if (entry != NULL) {
+               if (!NT_STATUS_IS_OK(entry->init(auth_context, module_params, ret))) {
+                       DEBUG(0,("load_auth_module: auth method %s did not correctly init\n",
+                                module_name));
+               } else {
+                       DEBUG(5,("load_auth_module: auth method %s has a valid init\n",
+                                module_name));
+                       good = True;
+               }
+       } else {
+               DEBUG(0,("load_auth_module: can't find auth method %s!\n", module_name));
+       }
+
+       SAFE_FREE(module_name);
+       return good;
+}
+
+/***************************************************************************
+ Make a auth_info struct for the auth subsystem
+***************************************************************************/
+
+static NTSTATUS make_auth_context_text_list(struct auth_context **auth_context, char **text_list) 
+{
+       auth_methods *list = NULL;
+       auth_methods *t = NULL;
+       auth_methods *tmp;
+       NTSTATUS nt_status;
+
+       if (!text_list) {
+               DEBUG(2,("make_auth_context_text_list: No auth method list!?\n"));
+               return NT_STATUS_UNSUCCESSFUL;
+       }
+       
+       if (!NT_STATUS_IS_OK(nt_status = make_auth_context(auth_context)))
+               return nt_status;
+
+       for (;*text_list; text_list++) { 
+               if (load_auth_module(*auth_context, *text_list, &t)) {
+                   DLIST_ADD_END(list, t, tmp);
+               }
+       }
+       
+       (*auth_context)->auth_method_list = list;
+       
+       return nt_status;
+}
+
+/***************************************************************************
+ Make a auth_context struct for the auth subsystem
+***************************************************************************/
+
+NTSTATUS make_auth_context_subsystem(struct auth_context **auth_context) 
+{
+       char **auth_method_list = NULL; 
+       NTSTATUS nt_status;
+
+       if (lp_auth_methods() && !str_list_copy(&auth_method_list, lp_auth_methods())) {
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       if (auth_method_list == NULL) {
+               switch (lp_security()) 
+               {
+               case SEC_DOMAIN:
+                       DEBUG(5,("Making default auth method list for security=domain\n"));
+                       auth_method_list = str_list_make("guest sam winbind:ntdomain", NULL);
+                       break;
+               case SEC_SERVER:
+                       DEBUG(5,("Making default auth method list for security=server\n"));
+                       auth_method_list = str_list_make("guest sam smbserver", NULL);
+                       break;
+               case SEC_USER:
+                       if (lp_encrypted_passwords()) { 
+                               if ((lp_server_role() == ROLE_DOMAIN_PDC) || (lp_server_role() == ROLE_DOMAIN_BDC)) {
+                                       DEBUG(5,("Making default auth method list for DC, security=user, encrypt passwords = yes\n"));
+                                       auth_method_list = str_list_make("guest sam winbind:trustdomain", NULL);
+                               } else {
+                                       DEBUG(5,("Making default auth method list for standalone security=user, encrypt passwords = yes\n"));
+                                       auth_method_list = str_list_make("guest sam", NULL);
+                               }
+                       } else {
+                               DEBUG(5,("Making default auth method list for security=user, encrypt passwords = no\n"));
+                               auth_method_list = str_list_make("guest unix", NULL);
+                       }
+                       break;
+               case SEC_SHARE:
+                       if (lp_encrypted_passwords()) {
+                               DEBUG(5,("Making default auth method list for security=share, encrypt passwords = yes\n"));
+                               auth_method_list = str_list_make("guest sam", NULL);
+                       } else {
+                               DEBUG(5,("Making default auth method list for security=share, encrypt passwords = no\n"));
+                               auth_method_list = str_list_make("guest unix", NULL);
+                       }
+                       break;
+               case SEC_ADS:
+                       DEBUG(5,("Making default auth method list for security=ADS\n"));
+                       auth_method_list = str_list_make("guest sam winbind:ntdomain", NULL);
+                       break;
+               default:
+                       DEBUG(5,("Unknown auth method!\n"));
+                       return NT_STATUS_UNSUCCESSFUL;
+               }
+       } else {
+               DEBUG(5,("Using specified auth order\n"));
+       }
+       
+       if (!NT_STATUS_IS_OK(nt_status = make_auth_context_text_list(auth_context, auth_method_list))) {
+               str_list_free(&auth_method_list);
+               return nt_status;
+       }
+       
+       str_list_free(&auth_method_list);
+       return nt_status;
+}
+
+/***************************************************************************
+ Make a auth_info struct with a fixed challenge
+***************************************************************************/
+
+NTSTATUS make_auth_context_fixed(struct auth_context **auth_context, uchar chal[8]) 
+{
+       NTSTATUS nt_status;
+       if (!NT_STATUS_IS_OK(nt_status = make_auth_context_subsystem(auth_context))) {
+               return nt_status;
+       }
+       
+       (*auth_context)->challenge = data_blob_talloc((*auth_context)->mem_ctx, chal, 8);
+       (*auth_context)->challenge_set_by = "fixed";
+       return nt_status;
+}
+
+