diff options
Diffstat (limited to 'crypto/openssh/gss-serv-krb5.c')
| -rw-r--r-- | crypto/openssh/gss-serv-krb5.c | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/crypto/openssh/gss-serv-krb5.c b/crypto/openssh/gss-serv-krb5.c new file mode 100644 index 000000000000..f48e0991150b --- /dev/null +++ b/crypto/openssh/gss-serv-krb5.c @@ -0,0 +1,205 @@ +/* $OpenBSD: gss-serv-krb5.c,v 1.1 2003/08/22 10:56:09 markus Exp $ */ + +/* + * Copyright (c) 2001-2003 Simon Wilkinson. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "includes.h" + +#ifdef GSSAPI +#ifdef KRB5 + +#include "auth.h" +#include "xmalloc.h" +#include "log.h" +#include "servconf.h" + +#include "ssh-gss.h" + +extern ServerOptions options; + +#ifdef HEIMDAL +#include <krb5.h> +#else +#include <gssapi_krb5.h> +#endif + +static krb5_context krb_context = NULL; + +/* Initialise the krb5 library, for the stuff that GSSAPI won't do */ + +static int +ssh_gssapi_krb5_init() +{ + krb5_error_code problem; + + if (krb_context != NULL) + return 1; + + problem = krb5_init_context(&krb_context); + if (problem) { + logit("Cannot initialize krb5 context"); + return 0; + } + krb5_init_ets(krb_context); + + return 1; +} + +/* Check if this user is OK to login. This only works with krb5 - other + * GSSAPI mechanisms will need their own. + * Returns true if the user is OK to log in, otherwise returns 0 + */ + +static int +ssh_gssapi_krb5_userok(ssh_gssapi_client *client, char *name) +{ + krb5_principal princ; + int retval; + + if (ssh_gssapi_krb5_init() == 0) + return 0; + + if ((retval = krb5_parse_name(krb_context, client->exportedname.value, + &princ))) { + logit("krb5_parse_name(): %.100s", + krb5_get_err_text(krb_context, retval)); + return 0; + } + if (krb5_kuserok(krb_context, princ, name)) { + retval = 1; + logit("Authorized to %s, krb5 principal %s (krb5_kuserok)", + name, (char *)client->displayname.value); + } else + retval = 0; + + krb5_free_principal(krb_context, princ); + return retval; +} + + +/* This writes out any forwarded credentials from the structure populated + * during userauth. Called after we have setuid to the user */ + +static void +ssh_gssapi_krb5_storecreds(ssh_gssapi_client *client) +{ + krb5_ccache ccache; + krb5_error_code problem; + krb5_principal princ; + OM_uint32 maj_status, min_status; + + if (client->creds == NULL) { + debug("No credentials stored"); + return; + } + + if (ssh_gssapi_krb5_init() == 0) + return; + +#ifdef HEIMDAL + if ((problem = krb5_cc_gen_new(krb_context, &krb5_fcc_ops, &ccache))) { + logit("krb5_cc_gen_new(): %.100s", + krb5_get_err_text(krb_context, problem)); + return; + } +#else + { + int tmpfd; + char ccname[40]; + + snprintf(ccname, sizeof(ccname), + "FILE:/tmp/krb5cc_%d_XXXXXX", geteuid()); + + if ((tmpfd = mkstemp(ccname + strlen("FILE:"))) == -1) { + logit("mkstemp(): %.100s", strerror(errno)); + problem = errno; + return; + } + if (fchmod(tmpfd, S_IRUSR | S_IWUSR) == -1) { + logit("fchmod(): %.100s", strerror(errno)); + close(tmpfd); + problem = errno; + return; + } + close(tmpfd); + if ((problem = krb5_cc_resolve(krb_context, ccname, &ccache))) { + logit("krb5_cc_resolve(): %.100s", + krb5_get_err_text(krb_context, problem)); + return; + } + } +#endif /* #ifdef HEIMDAL */ + + if ((problem = krb5_parse_name(krb_context, + client->exportedname.value, &princ))) { + logit("krb5_parse_name(): %.100s", + krb5_get_err_text(krb_context, problem)); + krb5_cc_destroy(krb_context, ccache); + return; + } + + if ((problem = krb5_cc_initialize(krb_context, ccache, princ))) { + logit("krb5_cc_initialize(): %.100s", + krb5_get_err_text(krb_context, problem)); + krb5_free_principal(krb_context, princ); + krb5_cc_destroy(krb_context, ccache); + return; + } + + krb5_free_principal(krb_context, princ); + + if ((maj_status = gss_krb5_copy_ccache(&min_status, + client->creds, ccache))) { + logit("gss_krb5_copy_ccache() failed"); + krb5_cc_destroy(krb_context, ccache); + return; + } + + client->store.filename = xstrdup(krb5_cc_get_name(krb_context, ccache)); + client->store.envvar = "KRB5CCNAME"; + client->store.envval = xstrdup(client->store.filename); + +#ifdef USE_PAM + if (options.use_pam) + do_pam_putenv(client->store.envvar,client->store.envval); +#endif + + krb5_cc_close(krb_context, ccache); + + return; +} + +ssh_gssapi_mech gssapi_kerberos_mech = { + "toWM5Slw5Ew8Mqkay+al2g==", + "Kerberos", + {9, "\x2A\x86\x48\x86\xF7\x12\x01\x02\x02"}, + NULL, + &ssh_gssapi_krb5_userok, + NULL, + &ssh_gssapi_krb5_storecreds +}; + +#endif /* KRB5 */ + +#endif /* GSSAPI */ |