1 /* $OpenBSD: auth.h,v 1.78 2014/07/03 11:16:55 djm Exp $ */ 2 3 /* 4 * Copyright (c) 2000 Markus Friedl. 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 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 */ 27 28 #ifndef AUTH_H 29 #define AUTH_H 30 31 #include <signal.h> 32 33 #include <openssl/rsa.h> 34 35 #include <bsd_auth.h> 36 #ifdef KRB5 37 #include <krb5.h> 38 #endif 39 40 typedef struct Authctxt Authctxt; 41 typedef struct Authmethod Authmethod; 42 typedef struct KbdintDevice KbdintDevice; 43 44 struct Authctxt { 45 sig_atomic_t success; 46 int authenticated; /* authenticated and alarms cancelled */ 47 int postponed; /* authentication needs another step */ 48 int valid; /* user exists and is allowed to login */ 49 int attempt; 50 int failures; 51 int server_caused_failure; 52 int force_pwchange; 53 char *user; /* username sent by the client */ 54 char *service; 55 struct passwd *pw; /* set if 'valid' */ 56 char *style; 57 void *kbdintctxt; 58 char *info; /* Extra info for next auth_log */ 59 auth_session_t *as; 60 char **auth_methods; /* modified from server config */ 61 u_int num_auth_methods; 62 #ifdef KRB5 63 krb5_context krb5_ctx; 64 krb5_ccache krb5_fwd_ccache; 65 krb5_principal krb5_user; 66 char *krb5_ticket_file; 67 #endif 68 void *methoddata; 69 }; 70 /* 71 * Every authentication method has to handle authentication requests for 72 * non-existing users, or for users that are not allowed to login. In this 73 * case 'valid' is set to 0, but 'user' points to the username requested by 74 * the client. 75 */ 76 77 struct Authmethod { 78 char *name; 79 int (*userauth)(Authctxt *authctxt); 80 int *enabled; 81 }; 82 83 /* 84 * Keyboard interactive device: 85 * init_ctx returns: non NULL upon success 86 * query returns: 0 - success, otherwise failure 87 * respond returns: 0 - success, 1 - need further interaction, 88 * otherwise - failure 89 */ 90 struct KbdintDevice 91 { 92 const char *name; 93 void* (*init_ctx)(Authctxt*); 94 int (*query)(void *ctx, char **name, char **infotxt, 95 u_int *numprompts, char ***prompts, u_int **echo_on); 96 int (*respond)(void *ctx, u_int numresp, char **responses); 97 void (*free_ctx)(void *ctx); 98 }; 99 100 int auth_rhosts(struct passwd *, const char *); 101 int 102 auth_rhosts2(struct passwd *, const char *, const char *, const char *); 103 104 int auth_rhosts_rsa(Authctxt *, char *, Key *); 105 int auth_password(Authctxt *, const char *); 106 int auth_rsa(Authctxt *, BIGNUM *); 107 int auth_rsa_challenge_dialog(Key *); 108 BIGNUM *auth_rsa_generate_challenge(Key *); 109 int auth_rsa_verify_response(Key *, BIGNUM *, u_char[]); 110 int auth_rsa_key_allowed(struct passwd *, BIGNUM *, Key **); 111 112 int auth_rhosts_rsa_key_allowed(struct passwd *, char *, char *, Key *); 113 int hostbased_key_allowed(struct passwd *, const char *, char *, Key *); 114 int user_key_allowed(struct passwd *, Key *); 115 void pubkey_auth_info(Authctxt *, const Key *, const char *, ...) 116 __attribute__((__format__ (printf, 3, 4))); 117 118 struct stat; 119 int auth_secure_path(const char *, struct stat *, const char *, uid_t, 120 char *, size_t); 121 122 #ifdef KRB5 123 int auth_krb5(Authctxt *authctxt, krb5_data *auth, char **client, krb5_data *); 124 int auth_krb5_tgt(Authctxt *authctxt, krb5_data *tgt); 125 int auth_krb5_password(Authctxt *authctxt, const char *password); 126 void krb5_cleanup_proc(Authctxt *authctxt); 127 #endif /* KRB5 */ 128 129 void do_authentication(Authctxt *); 130 void do_authentication2(Authctxt *); 131 132 void auth_info(Authctxt *authctxt, const char *, ...) 133 __attribute__((__format__ (printf, 2, 3))) 134 __attribute__((__nonnull__ (2))); 135 void auth_log(Authctxt *, int, int, const char *, const char *); 136 void auth_maxtries_exceeded(Authctxt *) __attribute__((noreturn)); 137 void userauth_finish(Authctxt *, int, const char *, const char *); 138 int auth_root_allowed(const char *); 139 140 char *auth2_read_banner(void); 141 int auth2_methods_valid(const char *, int); 142 int auth2_update_methods_lists(Authctxt *, const char *, const char *); 143 int auth2_setup_methods_lists(Authctxt *); 144 int auth2_method_allowed(Authctxt *, const char *, const char *); 145 146 void privsep_challenge_enable(void); 147 148 int auth2_challenge(Authctxt *, char *); 149 void auth2_challenge_stop(Authctxt *); 150 int bsdauth_query(void *, char **, char **, u_int *, char ***, u_int **); 151 int bsdauth_respond(void *, u_int, char **); 152 int skey_query(void *, char **, char **, u_int *, char ***, u_int **); 153 int skey_respond(void *, u_int, char **); 154 155 int allowed_user(struct passwd *); 156 struct passwd * getpwnamallow(const char *user); 157 158 char *get_challenge(Authctxt *); 159 int verify_response(Authctxt *, const char *); 160 161 char *expand_authorized_keys(const char *, struct passwd *pw); 162 char *authorized_principals_file(struct passwd *); 163 164 FILE *auth_openkeyfile(const char *, struct passwd *, int); 165 FILE *auth_openprincipals(const char *, struct passwd *, int); 166 int auth_key_is_revoked(Key *); 167 168 HostStatus 169 check_key_in_hostfiles(struct passwd *, Key *, const char *, 170 const char *, const char *); 171 172 /* hostkey handling */ 173 Key *get_hostkey_by_index(int); 174 Key *get_hostkey_public_by_index(int); 175 Key *get_hostkey_public_by_type(int); 176 Key *get_hostkey_private_by_type(int); 177 int get_hostkey_index(Key *); 178 int ssh1_session_key(BIGNUM *); 179 void sshd_hostkey_sign(Key *, Key *, u_char **, u_int *, u_char *, u_int); 180 181 /* debug messages during authentication */ 182 void auth_debug_add(const char *fmt,...) __attribute__((format(printf, 1, 2))); 183 void auth_debug_send(void); 184 void auth_debug_reset(void); 185 186 struct passwd *fakepw(void); 187 188 #endif 189