1 /* 2 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 4 * Copyright (c) 2016 by Delphix. All rights reserved. 5 */ 6 7 8 /* 9 * lib/krb5/krb/sendauth.c 10 * 11 * Copyright 1991 by the Massachusetts Institute of Technology. 12 * All Rights Reserved. 13 * 14 * Export of this software from the United States of America may 15 * require a specific license from the United States Government. 16 * It is the responsibility of any person or organization contemplating 17 * export to obtain such a license before exporting. 18 * 19 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and 20 * distribute this software and its documentation for any purpose and 21 * without fee is hereby granted, provided that the above copyright 22 * notice appear in all copies and that both that copyright notice and 23 * this permission notice appear in supporting documentation, and that 24 * the name of M.I.T. not be used in advertising or publicity pertaining 25 * to distribution of the software without specific, written prior 26 * permission. Furthermore if you modify this software you must label 27 * your software as modified software and not distribute it in such a 28 * fashion that it might be confused with the original M.I.T. software. 29 * M.I.T. makes no representations about the suitability of 30 * this software for any purpose. It is provided "as is" without express 31 * or implied warranty. 32 * 33 * 34 * convenience sendauth/recvauth functions 35 */ 36 37 38 #include "k5-int.h" 39 #include "com_err.h" 40 #include "auth_con.h" 41 #include <errno.h> 42 #include <stdio.h> 43 #include <string.h> 44 45 static const char sendauth_version[] = "KRB5_SENDAUTH_V1.0"; 46 47 krb5_error_code KRB5_CALLCONV 48 krb5_sendauth(krb5_context context, krb5_auth_context *auth_context, krb5_pointer fd, char *appl_version, krb5_principal client, krb5_principal server, krb5_flags ap_req_options, krb5_data *in_data, krb5_creds *in_creds, krb5_ccache ccache, krb5_error **error, krb5_ap_rep_enc_part **rep_result, krb5_creds **out_creds) 49 { 50 krb5_octet result; 51 krb5_creds creds; 52 krb5_creds * credsp = NULL; 53 krb5_creds * credspout = NULL; 54 krb5_error_code retval = 0; 55 krb5_data inbuf, outbuf; 56 int len; 57 krb5_ccache use_ccache = 0; 58 59 if (error) 60 *error = 0; 61 62 /* 63 * First, send over the length of the sendauth version string; 64 * then, we send over the sendauth version. Next, we send 65 * over the length of the application version strings followed 66 * by the string itself. 67 */ 68 outbuf.length = strlen(sendauth_version) + 1; 69 outbuf.data = (char *) sendauth_version; 70 if ((retval = krb5_write_message(context, fd, &outbuf))) 71 return(retval); 72 outbuf.length = strlen(appl_version) + 1; 73 outbuf.data = appl_version; 74 if ((retval = krb5_write_message(context, fd, &outbuf))) 75 return(retval); 76 /* 77 * Now, read back a byte: 0 means no error, 1 means bad sendauth 78 * version, 2 means bad application version 79 */ 80 if ((len = krb5_net_read(context, *((int *) fd), (char *)&result, 1)) != 1) 81 return((len < 0) ? errno : ECONNABORTED); 82 if (result == 1) 83 return(KRB5_SENDAUTH_BADAUTHVERS); 84 else if (result == 2) 85 return(KRB5_SENDAUTH_BADAPPLVERS); 86 else if (result != 0) 87 return(KRB5_SENDAUTH_BADRESPONSE); 88 /* 89 * We're finished with the initial negotiations; let's get and 90 * send over the authentication header. (The AP_REQ message) 91 */ 92 93 /* 94 * If no credentials were provided, try getting it from the 95 * credentials cache. 96 */ 97 memset((char *)&creds, 0, sizeof(creds)); 98 99 /* 100 * See if we need to access the credentials cache 101 */ 102 if (!in_creds || !in_creds->ticket.length) { 103 if (ccache) 104 use_ccache = ccache; 105 /* Solaris Kerberos */ 106 else if ((retval = krb5int_cc_default(context, &use_ccache)) != 0) 107 goto error_return; 108 } 109 if (!in_creds) { 110 if ((retval = krb5_copy_principal(context, server, 111 &creds.server))) 112 goto error_return; 113 if (client) 114 retval = krb5_copy_principal(context, client, 115 &creds.client); 116 else 117 retval = krb5_cc_get_principal(context, use_ccache, 118 &creds.client); 119 if (retval) { 120 krb5_free_principal(context, creds.server); 121 goto error_return; 122 } 123 /* creds.times.endtime = 0; -- memset 0 takes care of this 124 zero means "as long as possible" */ 125 /* creds.keyblock.enctype = 0; -- as well as this. 126 zero means no session enctype 127 preference */ 128 in_creds = &creds; 129 } 130 if (!in_creds->ticket.length) { 131 /* Solaris Kerberos */ 132 if ((retval = krb5_get_credentials(context, 0, 133 use_ccache, in_creds, &credsp)) != 0) 134 goto error_return; 135 credspout = credsp; 136 } else { 137 credsp = in_creds; 138 } 139 140 if (ap_req_options & AP_OPTS_USE_SUBKEY) { 141 /* Provide some more fodder for random number code. 142 This isn't strong cryptographically; the point here is 143 not to guarantee randomness, but to make it less likely 144 that multiple sessions could pick the same subkey. */ 145 char rnd_data[1024]; 146 GETPEERNAME_ARG3_TYPE len2; 147 krb5_data d; 148 d.length = sizeof (rnd_data); 149 d.data = rnd_data; 150 len2 = sizeof (rnd_data); 151 if (getpeername (*(int*)fd, (GETPEERNAME_ARG2_TYPE *) rnd_data, 152 &len2) == 0) { 153 d.length = len2; 154 /* Solaris Kerberos */ 155 (void) krb5_c_random_seed (context, &d); 156 } 157 len2 = sizeof (rnd_data); 158 if (getsockname (*(int*)fd, (GETSOCKNAME_ARG2_TYPE *) rnd_data, 159 &len2) == 0) { 160 d.length = len2; 161 /* Solaris Kerberos */ 162 (void) krb5_c_random_seed (context, &d); 163 } 164 } 165 166 /* Solaris Kerberos */ 167 if ((retval = krb5_mk_req_extended(context, auth_context, 168 ap_req_options, in_data, credsp, 169 &outbuf)) != 0) 170 goto error_return; 171 172 /* 173 * First write the length of the AP_REQ message, then write 174 * the message itself. 175 */ 176 retval = krb5_write_message(context, fd, &outbuf); 177 free(outbuf.data); 178 if (retval) 179 goto error_return; 180 181 /* 182 * Now, read back a message. If it was a null message (the 183 * length was zero) then there was no error. If not, we the 184 * authentication was rejected, and we need to return the 185 * error structure. 186 */ 187 /* Solaris Kerberos */ 188 if ((retval = krb5_read_message(context, fd, &inbuf)) != 0) 189 goto error_return; 190 191 if (inbuf.length) { 192 if (error) { 193 /* Solaris Kerberos */ 194 if ((retval = krb5_rd_error(context, &inbuf, error)) != 0) { 195 krb5_xfree(inbuf.data); 196 goto error_return; 197 } 198 } 199 retval = KRB5_SENDAUTH_REJECTED; 200 krb5_xfree(inbuf.data); 201 goto error_return; 202 } 203 204 /* 205 * If we asked for mutual authentication, we should now get a 206 * length field, followed by a AP_REP message 207 */ 208 if ((ap_req_options & AP_OPTS_MUTUAL_REQUIRED)) { 209 krb5_ap_rep_enc_part *repl = 0; 210 /* Solaris Kerberos */ 211 if ((retval = krb5_read_message(context, fd, &inbuf)) != 0) 212 goto error_return; 213 214 /* Solaris Kerberos */ 215 if ((retval = krb5_rd_rep(context, *auth_context, &inbuf, 216 &repl)) != 0) { 217 if (repl) 218 krb5_free_ap_rep_enc_part(context, repl); 219 krb5_xfree(inbuf.data); 220 goto error_return; 221 } 222 223 krb5_xfree(inbuf.data); 224 /* 225 * If the user wants to look at the AP_REP message, 226 * copy it for them. 227 */ 228 if (rep_result) 229 *rep_result = repl; 230 else 231 krb5_free_ap_rep_enc_part(context, repl); 232 } 233 retval = 0; /* Normal return */ 234 if (out_creds) { 235 *out_creds = credsp; 236 credspout = NULL; 237 } 238 239 error_return: 240 krb5_free_cred_contents(context, &creds); 241 if (credspout != NULL) 242 krb5_free_creds(context, credspout); 243 /* Solaris Kerberos */ 244 if (!ccache && use_ccache) 245 (void) krb5_cc_close(context, use_ccache); 246 return(retval); 247 } 248 249 250