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/* |
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* Copyright (c) 1998 - 2005 Kungliga Tekniska Högskolan |
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* (Royal Institute of Technology, Stockholm, Sweden). |
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* All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* |
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* 3. Neither the name of the Institute nor the names of its contributors |
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* may be used to endorse or promote products derived from this software |
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* without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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*/ |
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|
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#ifdef FTP_SERVER |
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#include "ftpd_locl.h" |
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#else |
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#include "ftp_locl.h" |
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#endif |
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#include <gssapi/gssapi.h> |
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#include <gssapi/gssapi_krb5.h> |
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#include <krb5_err.h> |
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|
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RCSID("$Id$"); |
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|
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int ftp_do_gss_bindings = 0; |
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int ftp_do_gss_delegate = 1; |
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|
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struct gssapi_data { |
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gss_ctx_id_t context_hdl; |
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gss_name_t client_name; |
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gss_cred_id_t delegated_cred_handle; |
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void *mech_data; |
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}; |
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|
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static int |
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gss_init(void *app_data) |
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{ |
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struct gssapi_data *d = app_data; |
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d->context_hdl = GSS_C_NO_CONTEXT; |
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d->delegated_cred_handle = GSS_C_NO_CREDENTIAL; |
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#if defined(FTP_SERVER) |
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return 0; |
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#else |
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/* XXX Check the gss mechanism; with gss_indicate_mechs() ? */ |
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#ifdef KRB5 |
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return !use_kerberos; |
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#else |
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return 0; |
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#endif /* KRB5 */ |
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#endif /* FTP_SERVER */ |
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} |
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|
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static int |
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gss_check_prot(void *app_data, int level) |
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{ |
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if(level == prot_confidential) |
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return -1; |
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return 0; |
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} |
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|
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static int |
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gss_decode(void *app_data, void *buf, int len, int level) |
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{ |
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OM_uint32 maj_stat, min_stat; |
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gss_buffer_desc input, output; |
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gss_qop_t qop_state; |
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int conf_state; |
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struct gssapi_data *d = app_data; |
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size_t ret_len; |
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|
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input.length = len; |
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input.value = buf; |
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maj_stat = gss_unwrap (&min_stat, |
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d->context_hdl, |
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&input, |
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&output, |
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&conf_state, |
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&qop_state); |
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if(GSS_ERROR(maj_stat)) |
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return -1; |
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memmove(buf, output.value, output.length); |
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ret_len = output.length; |
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gss_release_buffer(&min_stat, &output); |
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return ret_len; |
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} |
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|
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static int |
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gss_overhead(void *app_data, int level, int len) |
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{ |
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return 100; /* dunno? */ |
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} |
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|
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|
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static int |
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gss_encode(void *app_data, void *from, int length, int level, void **to) |
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{ |
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OM_uint32 maj_stat, min_stat; |
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gss_buffer_desc input, output; |
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int conf_state; |
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struct gssapi_data *d = app_data; |
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|
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input.length = length; |
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input.value = from; |
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maj_stat = gss_wrap (&min_stat, |
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d->context_hdl, |
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level == prot_private, |
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GSS_C_QOP_DEFAULT, |
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&input, |
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&conf_state, |
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&output); |
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*to = output.value; |
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return output.length; |
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} |
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|
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static void |
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sockaddr_to_gss_address (struct sockaddr *sa, |
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OM_uint32 *addr_type, |
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gss_buffer_desc *gss_addr) |
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{ |
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switch (sa->sa_family) { |
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#ifdef HAVE_IPV6 |
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case AF_INET6 : { |
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struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sa; |
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|
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gss_addr->length = 16; |
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gss_addr->value = &sin6->sin6_addr; |
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*addr_type = GSS_C_AF_INET6; |
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break; |
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} |
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#endif |
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case AF_INET : { |
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struct sockaddr_in *sin4 = (struct sockaddr_in *)sa; |
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|
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gss_addr->length = 4; |
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gss_addr->value = &sin4->sin_addr; |
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*addr_type = GSS_C_AF_INET; |
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break; |
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} |
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default : |
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errx (1, "unknown address family %d", sa->sa_family); |
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|
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} |
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} |
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|
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/* end common stuff */ |
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|
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#ifdef FTP_SERVER |
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|
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static int |
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gss_adat(void *app_data, void *buf, size_t len) |
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{ |
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char *p = NULL; |
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gss_buffer_desc input_token, output_token; |
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OM_uint32 maj_stat, min_stat; |
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gss_name_t client_name; |
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struct gssapi_data *d = app_data; |
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gss_channel_bindings_t bindings; |
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|
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if (ftp_do_gss_bindings) { |
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bindings = malloc(sizeof(*bindings)); |
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if (bindings == NULL) |
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errx(1, "out of memory"); |
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|
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sockaddr_to_gss_address (his_addr, |
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&bindings->initiator_addrtype, |
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&bindings->initiator_address); |
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sockaddr_to_gss_address (ctrl_addr, |
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&bindings->acceptor_addrtype, |
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&bindings->acceptor_address); |
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|
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bindings->application_data.length = 0; |
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bindings->application_data.value = NULL; |
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} else |
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bindings = GSS_C_NO_CHANNEL_BINDINGS; |
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|
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input_token.value = buf; |
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input_token.length = len; |
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|
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maj_stat = gss_accept_sec_context (&min_stat, |
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&d->context_hdl, |
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GSS_C_NO_CREDENTIAL, |
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&input_token, |
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bindings, |
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&client_name, |
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NULL, |
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&output_token, |
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NULL, |
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NULL, |
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&d->delegated_cred_handle); |
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|
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if (bindings != GSS_C_NO_CHANNEL_BINDINGS) |
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free(bindings); |
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|
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if(output_token.length) { |
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if(base64_encode(output_token.value, output_token.length, &p) < 0) { |
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reply(535, "Out of memory base64-encoding."); |
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return -1; |
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} |
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gss_release_buffer(&min_stat, &output_token); |
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} |
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if(maj_stat == GSS_S_COMPLETE){ |
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d->client_name = client_name; |
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client_name = GSS_C_NO_NAME; |
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if(p) |
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reply(235, "ADAT=%s", p); |
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else |
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reply(235, "ADAT Complete"); |
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sec_complete = 1; |
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|
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} else if(maj_stat == GSS_S_CONTINUE_NEEDED) { |
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if(p) |
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reply(335, "ADAT=%s", p); |
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else |
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reply(335, "OK, need more data"); |
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} else { |
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OM_uint32 new_stat; |
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OM_uint32 msg_ctx = 0; |
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gss_buffer_desc status_string; |
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gss_display_status(&new_stat, |
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min_stat, |
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GSS_C_MECH_CODE, |
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GSS_C_NO_OID, |
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&msg_ctx, |
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&status_string); |
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syslog(LOG_ERR, "gss_accept_sec_context: %.*s", |
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(int)status_string.length, |
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(char*)status_string.value); |
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gss_release_buffer(&new_stat, &status_string); |
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reply(431, "Security resource unavailable"); |
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} |
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|
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if (client_name) |
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gss_release_name(&min_stat, &client_name); |
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free(p); |
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return 0; |
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} |
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|
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int gssapi_userok(void*, char*); |
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int gssapi_session(void*, char*); |
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|
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struct sec_server_mech gss_server_mech = { |
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"GSSAPI", |
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sizeof(struct gssapi_data), |
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gss_init, /* init */ |
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NULL, /* end */ |
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gss_check_prot, |
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gss_overhead, |
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gss_encode, |
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gss_decode, |
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/* */ |
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NULL, |
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gss_adat, |
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NULL, /* pbsz */ |
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NULL, /* ccc */ |
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gssapi_userok, |
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gssapi_session |
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}; |
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|
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#else /* FTP_SERVER */ |
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|
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extern struct sockaddr *hisctladdr, *myctladdr; |
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|
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static int |
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import_name(const char *kname, const char *host, gss_name_t *target_name) |
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{ |
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OM_uint32 maj_stat, min_stat; |
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gss_buffer_desc name; |
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char *str; |
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|
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name.length = asprintf(&str, "%s@%s", kname, host); |
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if (str == NULL) { |
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printf("Out of memory\n"); |
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return AUTH_ERROR; |
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} |
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name.value = str; |
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|
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maj_stat = gss_import_name(&min_stat, |
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&name, |
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GSS_C_NT_HOSTBASED_SERVICE, |
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target_name); |
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if (GSS_ERROR(maj_stat)) { |
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OM_uint32 new_stat; |
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OM_uint32 msg_ctx = 0; |
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gss_buffer_desc status_string; |
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|
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gss_display_status(&new_stat, |
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min_stat, |
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GSS_C_MECH_CODE, |
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GSS_C_NO_OID, |
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&msg_ctx, |
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&status_string); |
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printf("Error importing name %.*s: %.*s\n", |
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(int)name.length, |
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(char *)name.value, |
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(int)status_string.length, |
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(char *)status_string.value); |
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free(name.value); |
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gss_release_buffer(&new_stat, &status_string); |
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return AUTH_ERROR; |
| 320 |
} |
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free(name.value); |
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return 0; |
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} |
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|
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static int |
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gss_auth(void *app_data, char *host) |
| 327 |
{ |
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|
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OM_uint32 maj_stat, min_stat; |
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gss_name_t target_name; |
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gss_buffer_desc input, output_token; |
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int context_established = 0; |
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char *p; |
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int n; |
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gss_channel_bindings_t bindings; |
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struct gssapi_data *d = app_data; |
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OM_uint32 mech_flags = GSS_C_MUTUAL_FLAG | GSS_C_SEQUENCE_FLAG; |
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|
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const char *knames[] = { "ftp", "host", NULL }, **kname = knames; |
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|
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|
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if(import_name(*kname++, host, &target_name)) |
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return AUTH_ERROR; |
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|
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input.length = 0; |
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input.value = NULL; |
| 347 |
|
| 348 |
if (ftp_do_gss_bindings) { |
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bindings = malloc(sizeof(*bindings)); |
| 350 |
if (bindings == NULL) |
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errx(1, "out of memory"); |
| 352 |
|
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sockaddr_to_gss_address (myctladdr, |
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&bindings->initiator_addrtype, |
| 355 |
&bindings->initiator_address); |
| 356 |
sockaddr_to_gss_address (hisctladdr, |
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&bindings->acceptor_addrtype, |
| 358 |
&bindings->acceptor_address); |
| 359 |
|
| 360 |
bindings->application_data.length = 0; |
| 361 |
bindings->application_data.value = NULL; |
| 362 |
} else |
| 363 |
bindings = GSS_C_NO_CHANNEL_BINDINGS; |
| 364 |
|
| 365 |
if (ftp_do_gss_delegate) |
| 366 |
mech_flags |= GSS_C_DELEG_FLAG; |
| 367 |
|
| 368 |
while(!context_established) { |
| 369 |
maj_stat = gss_init_sec_context(&min_stat, |
| 370 |
GSS_C_NO_CREDENTIAL, |
| 371 |
&d->context_hdl, |
| 372 |
target_name, |
| 373 |
GSS_C_NO_OID, |
| 374 |
mech_flags, |
| 375 |
0, |
| 376 |
bindings, |
| 377 |
&input, |
| 378 |
NULL, |
| 379 |
&output_token, |
| 380 |
NULL, |
| 381 |
NULL); |
| 382 |
if (GSS_ERROR(maj_stat)) { |
| 383 |
OM_uint32 new_stat; |
| 384 |
OM_uint32 msg_ctx = 0; |
| 385 |
gss_buffer_desc status_string; |
| 386 |
|
| 387 |
d->context_hdl = GSS_C_NO_CONTEXT; |
| 388 |
|
| 389 |
gss_release_name(&min_stat, &target_name); |
| 390 |
|
| 391 |
if(*kname != NULL) { |
| 392 |
|
| 393 |
if(import_name(*kname++, host, &target_name)) { |
| 394 |
if (bindings != GSS_C_NO_CHANNEL_BINDINGS) |
| 395 |
free(bindings); |
| 396 |
return AUTH_ERROR; |
| 397 |
} |
| 398 |
continue; |
| 399 |
} |
| 400 |
|
| 401 |
if (bindings != GSS_C_NO_CHANNEL_BINDINGS) |
| 402 |
free(bindings); |
| 403 |
|
| 404 |
gss_display_status(&new_stat, |
| 405 |
min_stat, |
| 406 |
GSS_C_MECH_CODE, |
| 407 |
GSS_C_NO_OID, |
| 408 |
&msg_ctx, |
| 409 |
&status_string); |
| 410 |
printf("Error initializing security context: %.*s\n", |
| 411 |
(int)status_string.length, |
| 412 |
(char*)status_string.value); |
| 413 |
gss_release_buffer(&new_stat, &status_string); |
| 414 |
return AUTH_CONTINUE; |
| 415 |
} |
| 416 |
|
| 417 |
if (input.value) { |
| 418 |
free(input.value); |
| 419 |
input.value = NULL; |
| 420 |
input.length = 0; |
| 421 |
} |
| 422 |
if (output_token.length != 0) { |
| 423 |
base64_encode(output_token.value, output_token.length, &p); |
| 424 |
gss_release_buffer(&min_stat, &output_token); |
| 425 |
n = command("ADAT %s", p); |
| 426 |
free(p); |
| 427 |
} |
| 428 |
if (GSS_ERROR(maj_stat)) { |
| 429 |
if (d->context_hdl != GSS_C_NO_CONTEXT) |
| 430 |
gss_delete_sec_context (&min_stat, |
| 431 |
&d->context_hdl, |
| 432 |
GSS_C_NO_BUFFER); |
| 433 |
break; |
| 434 |
} |
| 435 |
if (maj_stat & GSS_S_CONTINUE_NEEDED) { |
| 436 |
p = strstr(reply_string, "ADAT="); |
| 437 |
if(p == NULL){ |
| 438 |
printf("Error: expected ADAT in reply. got: %s\n", |
| 439 |
reply_string); |
| 440 |
if (bindings != GSS_C_NO_CHANNEL_BINDINGS) |
| 441 |
free(bindings); |
| 442 |
return AUTH_ERROR; |
| 443 |
} else { |
| 444 |
p+=5; |
| 445 |
input.value = malloc(strlen(p)); |
| 446 |
input.length = base64_decode(p, input.value); |
| 447 |
} |
| 448 |
} else { |
| 449 |
if(code != 235) { |
| 450 |
printf("Unrecognized response code: %d\n", code); |
| 451 |
if (bindings != GSS_C_NO_CHANNEL_BINDINGS) |
| 452 |
free(bindings); |
| 453 |
return AUTH_ERROR; |
| 454 |
} |
| 455 |
context_established = 1; |
| 456 |
} |
| 457 |
} |
| 458 |
|
| 459 |
gss_release_name(&min_stat, &target_name); |
| 460 |
|
| 461 |
if (bindings != GSS_C_NO_CHANNEL_BINDINGS) |
| 462 |
free(bindings); |
| 463 |
if (input.value) |
| 464 |
free(input.value); |
| 465 |
|
| 466 |
{ |
| 467 |
gss_name_t targ_name; |
| 468 |
|
| 469 |
maj_stat = gss_inquire_context(&min_stat, |
| 470 |
d->context_hdl, |
| 471 |
NULL, |
| 472 |
&targ_name, |
| 473 |
NULL, |
| 474 |
NULL, |
| 475 |
NULL, |
| 476 |
NULL, |
| 477 |
NULL); |
| 478 |
if (GSS_ERROR(maj_stat) == 0) { |
| 479 |
gss_buffer_desc name; |
| 480 |
maj_stat = gss_display_name (&min_stat, |
| 481 |
targ_name, |
| 482 |
&name, |
| 483 |
NULL); |
| 484 |
if (GSS_ERROR(maj_stat) == 0) { |
| 485 |
printf("Authenticated to <%.*s>\n", |
| 486 |
(int)name.length, |
| 487 |
(char *)name.value); |
| 488 |
gss_release_buffer(&min_stat, &name); |
| 489 |
} |
| 490 |
gss_release_name(&min_stat, &targ_name); |
| 491 |
} else |
| 492 |
printf("Failed to get gss name of peer.\n"); |
| 493 |
} |
| 494 |
|
| 495 |
|
| 496 |
return AUTH_OK; |
| 497 |
} |
| 498 |
|
| 499 |
struct sec_client_mech gss_client_mech = { |
| 500 |
"GSSAPI", |
| 501 |
sizeof(struct gssapi_data), |
| 502 |
gss_init, |
| 503 |
gss_auth, |
| 504 |
NULL, /* end */ |
| 505 |
gss_check_prot, |
| 506 |
gss_overhead, |
| 507 |
gss_encode, |
| 508 |
gss_decode, |
| 509 |
}; |
| 510 |
|
| 511 |
#endif /* FTP_SERVER */ |
