1 /* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */ 2 /* 3 * Copyright (C) 2013 by the Massachusetts Institute of Technology. 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * * Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * * Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 22 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 23 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 25 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 27 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 29 * OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Declarations for localauth plugin module implementors. 34 * 35 * The localauth pluggable interface currently has only one supported major 36 * version, which is 1. Major version 1 has a current minor version number of 37 * 1. 38 * 39 * Localauth plugin modules should define a function named 40 * localauth_<modulename>_initvt, matching the signature: 41 * 42 * krb5_error_code 43 * localauth_modname_initvt(krb5_context context, int maj_ver, int min_ver, 44 * krb5_plugin_vtable vtable); 45 * 46 * The initvt function should: 47 * 48 * - Check that the supplied maj_ver number is supported by the module, or 49 * return KRB5_PLUGIN_VER_NOTSUPP if it is not. 50 * 51 * - Cast the vtable pointer as appropriate for maj_ver: 52 * maj_ver == 1: Cast to krb5_localauth_vtable 53 * 54 * - Initialize the methods of the vtable, stopping as appropriate for the 55 * supplied min_ver. Optional methods may be left uninitialized. 56 * 57 * Memory for the vtable is allocated by the caller, not by the module. 58 */ 59 60 #ifndef KRB5_LOCALAUTH_PLUGIN_H 61 #define KRB5_LOCALAUTH_PLUGIN_H 62 63 #include <krb5/krb5.h> 64 #include <krb5/plugin.h> 65 66 /* An abstract type for localauth module data. */ 67 typedef struct krb5_localauth_moddata_st *krb5_localauth_moddata; 68 69 /*** Method type declarations ***/ 70 71 /* Optional: Initialize module data. */ 72 typedef krb5_error_code 73 (*krb5_localauth_init_fn)(krb5_context context, 74 krb5_localauth_moddata *data); 75 76 /* Optional: Release resources used by module data. */ 77 typedef void 78 (*krb5_localauth_fini_fn)(krb5_context context, krb5_localauth_moddata data); 79 80 /* 81 * Optional: Determine whether aname is authorized to log in as the local 82 * account lname. Return 0 if aname is authorized, EPERM if aname is 83 * authoritatively not authorized, KRB5_PLUGIN_NO_HANDLE if the module cannot 84 * determine whether aname is authorized, and any other error code for a 85 * serious failure to process the request. aname will be considered authorized 86 * if at least one module returns 0 and all other modules return 87 * KRB5_PLUGIN_NO_HANDLE. 88 */ 89 typedef krb5_error_code 90 (*krb5_localauth_userok_fn)(krb5_context context, krb5_localauth_moddata data, 91 krb5_const_principal aname, const char *lname); 92 93 /* 94 * Optional (mandatory if an2ln_types is set): Determine the local account name 95 * corresponding to aname. Return 0 and set *lname_out if a mapping can be 96 * determined; the contents of *lname_out will later be released with a call to 97 * the module's free_string method. Return KRB5_LNAME_NOTRANS if no mapping 98 * can be determined. Return any other error code for a serious failure to 99 * process the request; this will halt the krb5_aname_to_localname operation. 100 * 101 * If the module's an2ln_types field is set, this method will only be invoked 102 * when a profile "auth_to_local" value references one of the module's types. 103 * type and residual will be set to the type and residual of the auth_to_local 104 * value. 105 * 106 * If the module's an2ln_types field is not set but the an2ln method is 107 * implemented, this method will be invoked independently of the profile's 108 * auth_to_local settings, with type and residual set to NULL. If multiple 109 * modules are registered with an2ln methods but no an2ln_types field, the 110 * order of invocation is not defined, but all such modules will be consulted 111 * before the built-in mechanisms are tried. 112 */ 113 typedef krb5_error_code 114 (*krb5_localauth_an2ln_fn)(krb5_context context, krb5_localauth_moddata data, 115 const char *type, const char *residual, 116 krb5_const_principal aname, char **lname_out); 117 118 /* 119 * Optional (mandatory if an2ln is implemented): Release the memory returned by 120 * an invocation of an2ln. 121 */ 122 typedef void 123 (*krb5_localauth_free_string_fn)(krb5_context context, 124 krb5_localauth_moddata data, char *str); 125 126 /* localauth vtable for major version 1. */ 127 typedef struct krb5_localauth_vtable_st { 128 const char *name; /* Mandatory: name of module. */ 129 const char **an2ln_types; /* Optional: uppercase auth_to_local types */ 130 krb5_localauth_init_fn init; 131 krb5_localauth_fini_fn fini; 132 krb5_localauth_userok_fn userok; 133 krb5_localauth_an2ln_fn an2ln; 134 krb5_localauth_free_string_fn free_string; 135 /* Minor version 1 ends here. */ 136 } *krb5_localauth_vtable; 137 138 #endif /* KRB5_LOCALAUTH_PLUGIN_H */ 139