1/* $NetBSD: sendauth.c,v 1.2 2017/01/28 21:31:49 christos Exp $ */ 2 3/* 4 * Copyright (c) 1997 - 2006 Kungliga Tekniska H��gskolan 5 * (Royal Institute of Technology, Stockholm, Sweden). 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * 3. Neither the name of the Institute nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36#include "krb5_locl.h" 37 38/* 39 * The format seems to be: 40 * client -> server 41 * 42 * 4 bytes - length 43 * KRB5_SENDAUTH_V1.0 (including zero) 44 * 4 bytes - length 45 * protocol string (with terminating zero) 46 * 47 * server -> client 48 * 1 byte - (0 = OK, else some kind of error) 49 * 50 * client -> server 51 * 4 bytes - length 52 * AP-REQ 53 * 54 * server -> client 55 * 4 bytes - length (0 = OK, else length of error) 56 * (error) 57 * 58 * if(mutual) { 59 * server -> client 60 * 4 bytes - length 61 * AP-REP 62 * } 63 */ 64 65/** 66 * Perform the client side of the sendauth protocol. 67 * 68 * @param context Kerberos 5 context. 69 * @param auth_context Authentication context of the peer. 70 * @param p_fd Socket associated to the connection. 71 * @param appl_version Server-specific string. 72 * @param client Client principal. If NULL, use the credentials in \a ccache. 73 * @param server Server principal. 74 * @param ap_req_options Options for the AP_REQ message. See the AP_OPTS_* defines in krb5.h. 75 * @param in_data FIXME 76 * @param in_creds FIXME 77 * @param ccache Credentials cache. If NULL, use the default credentials cache. 78 * @param ret_error If not NULL, will be set to the error reported by server, if any. 79 * Must be deallocated with krb5_free_error_contents(). 80 * @param rep_result If not NULL, will be set to the EncApRepPart of the AP_REP message. 81 * Must be deallocated with krb5_free_ap_rep_enc_part(). 82 * @param out_creds FIXME If not NULL, will be set to FIXME. Must be deallocated with 83 * krb5_free_creds(). 84 * 85 * @return 0 to indicate success. Otherwise a Kerberos error code is 86 * returned, see krb5_get_error_message(). 87 */ 88KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL 89krb5_sendauth(krb5_context context, 90 krb5_auth_context *auth_context, 91 krb5_pointer p_fd, 92 const char *appl_version, 93 krb5_principal client, 94 krb5_principal server, 95 krb5_flags ap_req_options, 96 krb5_data *in_data, 97 krb5_creds *in_creds, 98 krb5_ccache ccache, 99 krb5_error **ret_error, 100 krb5_ap_rep_enc_part **rep_result, 101 krb5_creds **out_creds) 102{ 103 krb5_error_code ret; 104 uint32_t len, net_len; 105 const char *version = KRB5_SENDAUTH_VERSION; 106 u_char repl; 107 krb5_data ap_req, error_data; 108 krb5_creds this_cred; 109 krb5_principal this_client = NULL; 110 krb5_creds *creds; 111 ssize_t sret; 112 krb5_boolean my_ccache = FALSE; 113 114 len = strlen(version) + 1; 115 net_len = htonl(len); 116 if (krb5_net_write (context, p_fd, &net_len, 4) != 4 117 || krb5_net_write (context, p_fd, version, len) != len) { 118 ret = errno; 119 krb5_set_error_message (context, ret, "write: %s", strerror(ret)); 120 return ret; 121 } 122 123 len = strlen(appl_version) + 1; 124 net_len = htonl(len); 125 if (krb5_net_write (context, p_fd, &net_len, 4) != 4 126 || krb5_net_write (context, p_fd, appl_version, len) != len) { 127 ret = errno; 128 krb5_set_error_message (context, ret, "write: %s", strerror(ret)); 129 return ret; 130 } 131 132 sret = krb5_net_read (context, p_fd, &repl, sizeof(repl)); 133 if (sret < 0) { 134 ret = errno; 135 krb5_set_error_message (context, ret, "read: %s", strerror(ret)); 136 return ret; 137 } else if (sret != sizeof(repl)) { 138 krb5_clear_error_message (context); 139 return KRB5_SENDAUTH_BADRESPONSE; 140 } 141 142 if (repl != 0) { 143 krb5_clear_error_message (context); 144 return KRB5_SENDAUTH_REJECTED; 145 } 146 147 if (in_creds == NULL) { 148 if (ccache == NULL) { 149 ret = krb5_cc_default (context, &ccache); 150 if (ret) 151 return ret; 152 my_ccache = TRUE; 153 } 154 155 if (client == NULL) { 156 ret = krb5_cc_get_principal (context, ccache, &this_client); 157 if (ret) { 158 if(my_ccache) 159 krb5_cc_close(context, ccache); 160 return ret; 161 } 162 client = this_client; 163 } 164 memset(&this_cred, 0, sizeof(this_cred)); 165 this_cred.client = client; 166 this_cred.server = server; 167 this_cred.times.endtime = 0; 168 this_cred.ticket.length = 0; 169 in_creds = &this_cred; 170 } 171 if (in_creds->ticket.length == 0) { 172 ret = krb5_get_credentials (context, 0, ccache, in_creds, &creds); 173 if (ret) { 174 if(my_ccache) 175 krb5_cc_close(context, ccache); 176 return ret; 177 } 178 } else { 179 creds = in_creds; 180 } 181 if(my_ccache) 182 krb5_cc_close(context, ccache); 183 ret = krb5_mk_req_extended (context, 184 auth_context, 185 ap_req_options, 186 in_data, 187 creds, 188 &ap_req); 189 190 if (out_creds) 191 *out_creds = creds; 192 else 193 krb5_free_creds(context, creds); 194 if(this_client) 195 krb5_free_principal(context, this_client); 196 197 if (ret) 198 return ret; 199 200 ret = krb5_write_message (context, 201 p_fd, 202 &ap_req); 203 if (ret) 204 return ret; 205 206 krb5_data_free (&ap_req); 207 208 ret = krb5_read_message (context, p_fd, &error_data); 209 if (ret) 210 return ret; 211 212 if (error_data.length != 0) { 213 KRB_ERROR error; 214 215 ret = krb5_rd_error (context, &error_data, &error); 216 krb5_data_free (&error_data); 217 if (ret == 0) { 218 ret = krb5_error_from_rd_error(context, &error, NULL); 219 if (ret_error != NULL) { 220 *ret_error = malloc (sizeof(krb5_error)); 221 if (*ret_error == NULL) { 222 krb5_free_error_contents (context, &error); 223 } else { 224 **ret_error = error; 225 } 226 } else { 227 krb5_free_error_contents (context, &error); 228 } 229 return ret; 230 } else { 231 krb5_clear_error_message(context); 232 return ret; 233 } 234 } else 235 krb5_data_free (&error_data); 236 237 if (ap_req_options & AP_OPTS_MUTUAL_REQUIRED) { 238 krb5_data ap_rep; 239 krb5_ap_rep_enc_part *ignore = NULL; 240 241 krb5_data_zero (&ap_rep); 242 ret = krb5_read_message (context, 243 p_fd, 244 &ap_rep); 245 if (ret) 246 return ret; 247 248 ret = krb5_rd_rep (context, *auth_context, &ap_rep, 249 rep_result ? rep_result : &ignore); 250 krb5_data_free (&ap_rep); 251 if (ret) 252 return ret; 253 if (rep_result == NULL) 254 krb5_free_ap_rep_enc_part (context, ignore); 255 } 256 return 0; 257} 258