1 /* $OpenBSD: auth.h,v 1.69 2011/05/23 03:30:07 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 #ifdef HAVE_LOGIN_CAP 36 #include <login_cap.h> 37 #endif 38 #ifdef BSD_AUTH 39 #include <bsd_auth.h> 40 #endif 41 #ifdef KRB5 42 #include <krb5.h> 43 #endif 44 45 typedef struct Authctxt Authctxt; 46 typedef struct Authmethod Authmethod; 47 typedef struct KbdintDevice KbdintDevice; 48 49 struct Authctxt { 50 sig_atomic_t success; 51 int authenticated; /* authenticated and alarms cancelled */ 52 int postponed; /* authentication needs another step */ 53 int valid; /* user exists and is allowed to login */ 54 int attempt; 55 int failures; 56 int server_caused_failure; 57 int force_pwchange; 58 char *user; /* username sent by the client */ 59 char *service; 60 struct passwd *pw; /* set if 'valid' */ 61 char *style; 62 void *kbdintctxt; 63 void *jpake_ctx; 64 #ifdef BSD_AUTH 65 auth_session_t *as; 66 #endif 67 #ifdef KRB5 68 krb5_context krb5_ctx; 69 krb5_ccache krb5_fwd_ccache; 70 krb5_principal krb5_user; 71 char *krb5_ticket_file; 72 char *krb5_ccname; 73 #endif 74 Buffer *loginmsg; 75 void *methoddata; 76 }; 77 /* 78 * Every authentication method has to handle authentication requests for 79 * non-existing users, or for users that are not allowed to login. In this 80 * case 'valid' is set to 0, but 'user' points to the username requested by 81 * the client. 82 */ 83 84 struct Authmethod { 85 char *name; 86 int (*userauth)(Authctxt *authctxt); 87 int *enabled; 88 }; 89 90 /* 91 * Keyboard interactive device: 92 * init_ctx returns: non NULL upon success 93 * query returns: 0 - success, otherwise failure 94 * respond returns: 0 - success, 1 - need further interaction, 95 * otherwise - failure 96 */ 97 struct KbdintDevice 98 { 99 const char *name; 100 void* (*init_ctx)(Authctxt*); 101 int (*query)(void *ctx, char **name, char **infotxt, 102 u_int *numprompts, char ***prompts, u_int **echo_on); 103 int (*respond)(void *ctx, u_int numresp, char **responses); 104 void (*free_ctx)(void *ctx); 105 }; 106 107 int auth_rhosts(struct passwd *, const char *); 108 int 109 auth_rhosts2(struct passwd *, const char *, const char *, const char *); 110 111 int auth_rhosts_rsa(Authctxt *, char *, Key *); 112 int auth_password(Authctxt *, const char *); 113 int auth_rsa(Authctxt *, BIGNUM *); 114 int auth_rsa_challenge_dialog(Key *); 115 BIGNUM *auth_rsa_generate_challenge(Key *); 116 int auth_rsa_verify_response(Key *, BIGNUM *, u_char[]); 117 int auth_rsa_key_allowed(struct passwd *, BIGNUM *, Key **); 118 119 int auth_rhosts_rsa_key_allowed(struct passwd *, char *, char *, Key *); 120 int hostbased_key_allowed(struct passwd *, const char *, char *, Key *); 121 int user_key_allowed(struct passwd *, Key *); 122 123 #ifdef KRB5 124 int auth_krb5(Authctxt *authctxt, krb5_data *auth, char **client, krb5_data *); 125 int auth_krb5_tgt(Authctxt *authctxt, krb5_data *tgt); 126 int auth_krb5_password(Authctxt *authctxt, const char *password); 127 void krb5_cleanup_proc(Authctxt *authctxt); 128 #endif /* KRB5 */ 129 130 #if defined(USE_SHADOW) && defined(HAS_SHADOW_EXPIRE) 131 #include <shadow.h> 132 int auth_shadow_acctexpired(struct spwd *); 133 int auth_shadow_pwexpired(Authctxt *); 134 #endif 135 136 #include "auth-pam.h" 137 #include "audit.h" 138 void remove_kbdint_device(const char *); 139 140 void disable_forwarding(void); 141 142 void do_authentication(Authctxt *); 143 void do_authentication2(Authctxt *); 144 145 void auth_log(Authctxt *, int, char *, char *); 146 void userauth_finish(Authctxt *, int, char *); 147 void userauth_send_banner(const char *); 148 int auth_root_allowed(char *); 149 150 char *auth2_read_banner(void); 151 152 void privsep_challenge_enable(void); 153 154 int auth2_challenge(Authctxt *, char *); 155 void auth2_challenge_stop(Authctxt *); 156 int bsdauth_query(void *, char **, char **, u_int *, char ***, u_int **); 157 int bsdauth_respond(void *, u_int, char **); 158 int skey_query(void *, char **, char **, u_int *, char ***, u_int **); 159 int skey_respond(void *, u_int, char **); 160 161 void auth2_jpake_get_pwdata(Authctxt *, BIGNUM **, char **, char **); 162 void auth2_jpake_stop(Authctxt *); 163 164 int allowed_user(struct passwd *); 165 struct passwd * getpwnamallow(const char *user); 166 167 char *get_challenge(Authctxt *); 168 int verify_response(Authctxt *, const char *); 169 void abandon_challenge_response(Authctxt *); 170 171 char *expand_authorized_keys(const char *, struct passwd *pw); 172 char *authorized_principals_file(struct passwd *); 173 174 FILE *auth_openkeyfile(const char *, struct passwd *, int); 175 FILE *auth_openprincipals(const char *, struct passwd *, int); 176 int auth_key_is_revoked(Key *); 177 178 HostStatus 179 check_key_in_hostfiles(struct passwd *, Key *, const char *, 180 const char *, const char *); 181 182 /* hostkey handling */ 183 Key *get_hostkey_by_index(int); 184 Key *get_hostkey_public_by_type(int); 185 Key *get_hostkey_private_by_type(int); 186 int get_hostkey_index(Key *); 187 int ssh1_session_key(BIGNUM *); 188 189 /* debug messages during authentication */ 190 void auth_debug_add(const char *fmt,...) __attribute__((format(printf, 1, 2))); 191 void auth_debug_send(void); 192 void auth_debug_reset(void); 193 194 struct passwd *fakepw(void); 195 196 int sys_auth_passwd(Authctxt *, const char *); 197 198 #define AUTH_FAIL_MSG "Too many authentication failures for %.100s" 199 200 #define SKEY_PROMPT "\nS/Key Password: " 201 202 #if defined(KRB5) && !defined(HEIMDAL) 203 #include <krb5.h> 204 krb5_error_code ssh_krb5_cc_gen(krb5_context, krb5_ccache *); 205 #endif 206 #endif 207
