+++ /dev/null
-/* $OpenBSD: gss-serv-krb5.c,v 1.7 2006/08/03 03:34:42 deraadt Exp $ */
-
-/*
- * Copyright (c) 2001-2007 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 <sys/types.h>
-
-#include <stdarg.h>
-#include <string.h>
-
-#include "xmalloc.h"
-#include "key.h"
-#include "hostfile.h"
-#include "auth.h"
-#include "log.h"
-#include "servconf.h"
-
-#include "buffer.h"
-#include "ssh-gss.h"
-
-extern ServerOptions options;
-
-#ifdef HEIMDAL
-# include <krb5.h>
-#else
-# ifdef HAVE_GSSAPI_KRB5_H
-# include <gssapi_krb5.h>
-# elif HAVE_GSSAPI_GSSAPI_KRB5_H
-# include <gssapi/gssapi_krb5.h>
-# endif
-#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(void)
-{
- 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;
- }
-
- 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;
- int len;
- const char *new_ccname;
-
- 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
- if ((problem = ssh_krb5_cc_gen(krb_context, &ccache))) {
- logit("ssh_krb5_cc_gen(): %.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;
- }
-
- new_ccname = krb5_cc_get_name(krb_context, ccache);
-
- client->store.envvar = "KRB5CCNAME";
-#ifdef USE_CCAPI
- xasprintf(&client->store.envval, "API:%s", new_ccname);
- client->store.filename = NULL;
-#else
- xasprintf(&client->store.envval, "FILE:%s", new_ccname);
- client->store.filename = xstrdup(new_ccname);
-#endif
-
-#ifdef USE_PAM
- if (options.use_pam)
- do_pam_putenv(client->store.envvar, client->store.envval);
-#endif
-
- krb5_cc_close(krb_context, ccache);
-
- return;
-}
-
-int
-ssh_gssapi_krb5_updatecreds(ssh_gssapi_ccache *store,
- ssh_gssapi_client *client)
-{
- krb5_ccache ccache = NULL;
- krb5_principal principal = NULL;
- char *name = NULL;
- krb5_error_code problem;
- OM_uint32 maj_status, min_status;
-
- if ((problem = krb5_cc_resolve(krb_context, store->envval, &ccache))) {
- logit("krb5_cc_resolve(): %.100s",
- krb5_get_err_text(krb_context, problem));
- return 0;
- }
-
- /* Find out who the principal in this cache is */
- if ((problem = krb5_cc_get_principal(krb_context, ccache,
- &principal))) {
- logit("krb5_cc_get_principal(): %.100s",
- krb5_get_err_text(krb_context, problem));
- krb5_cc_close(krb_context, ccache);
- return 0;
- }
-
- if ((problem = krb5_unparse_name(krb_context, principal, &name))) {
- logit("krb5_unparse_name(): %.100s",
- krb5_get_err_text(krb_context, problem));
- krb5_free_principal(krb_context, principal);
- krb5_cc_close(krb_context, ccache);
- return 0;
- }
-
-
- if (strcmp(name,client->exportedname.value)!=0) {
- debug("Name in local credentials cache differs. Not storing");
- krb5_free_principal(krb_context, principal);
- krb5_cc_close(krb_context, ccache);
- krb5_free_unparsed_name(krb_context, name);
- return 0;
- }
- krb5_free_unparsed_name(krb_context, name);
-
- /* Name matches, so lets get on with it! */
-
- if ((problem = krb5_cc_initialize(krb_context, ccache, principal))) {
- logit("krb5_cc_initialize(): %.100s",
- krb5_get_err_text(krb_context, problem));
- krb5_free_principal(krb_context, principal);
- krb5_cc_close(krb_context, ccache);
- return 0;
- }
-
- krb5_free_principal(krb_context, principal);
-
- if ((maj_status = gss_krb5_copy_ccache(&min_status, client->creds,
- ccache))) {
- logit("gss_krb5_copy_ccache() failed. Sorry!");
- krb5_cc_close(krb_context, ccache);
- return 0;
- }
-
- return 1;
-}
-
-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,
- &ssh_gssapi_krb5_updatecreds
-};
-
-#endif /* KRB5 */
-
-#endif /* GSSAPI */
static ssh_gssapi_client gssapi_client =
{ GSS_C_EMPTY_BUFFER, GSS_C_EMPTY_BUFFER,
- GSS_C_NO_CREDENTIAL, GSS_C_NO_NAME, NULL, {NULL, NULL, NULL}, 0, 0};
-
-ssh_gssapi_mech gssapi_null_mech =
- { NULL, NULL, {0, NULL}, NULL, NULL, NULL, NULL, NULL};
-
-#ifdef KRB5
-extern ssh_gssapi_mech gssapi_kerberos_mech;
-#endif
-
-ssh_gssapi_mech* supported_mechs[]= {
-#ifdef KRB5
- &gssapi_kerberos_mech,
-#endif
- &gssapi_null_mech,
-};
-
+ GSS_C_NO_CREDENTIAL, GSS_C_NO_NAME, {NULL, NULL, NULL}, 0, 0};
/*
* Acquire credentials for a server running on the current host.
void
ssh_gssapi_supported_oids(gss_OID_set *oidset)
{
- int i = 0;
OM_uint32 min_status;
- int present;
- gss_OID_set supported;
-
- gss_create_empty_oid_set(&min_status, oidset);
-
- if (GSS_ERROR(gss_indicate_mechs(&min_status, &supported)))
- return;
-
- while (supported_mechs[i]->name != NULL) {
- if (GSS_ERROR(gss_test_oid_set_member(&min_status,
- &supported_mechs[i]->oid, supported, &present)))
- present = 0;
- if (present)
- gss_add_oid_set_member(&min_status,
- &supported_mechs[i]->oid, oidset);
- i++;
- }
- gss_release_oid_set(&min_status, &supported);
+ gss_indicate_mechs(&min_status, oidset);
}
OM_uint32
ssh_gssapi_getclient(Gssctxt *ctx, ssh_gssapi_client *client)
{
- int i = 0;
- int equal = 0;
- gss_name_t new_name = GSS_C_NO_NAME;
- gss_buffer_desc ename = GSS_C_EMPTY_BUFFER;
-
- if (options.gss_store_rekey && client->used && ctx->client_creds) {
- if (client->mech->oid.length != ctx->oid->length ||
- (memcmp(client->mech->oid.elements,
- ctx->oid->elements, ctx->oid->length) !=0)) {
- debug("Rekeyed credentials have different mechanism");
- return GSS_S_COMPLETE;
- }
-
- if ((ctx->major = gss_inquire_cred_by_mech(&ctx->minor,
- ctx->client_creds, ctx->oid, &new_name,
- NULL, NULL, NULL))) {
- ssh_gssapi_error(ctx);
- return (ctx->major);
- }
-
- ctx->major = gss_compare_name(&ctx->minor, client->name,
- new_name, &equal);
-
- if (GSS_ERROR(ctx->major)) {
- ssh_gssapi_error(ctx);
- return (ctx->major);
- }
-
- if (!equal) {
- debug("Rekeyed credentials have different name");
- return GSS_S_COMPLETE;
- }
-
- debug("Marking rekeyed credentials for export");
-
- gss_release_name(&ctx->minor, &client->name);
- gss_release_cred(&ctx->minor, &client->creds);
- client->name = new_name;
- client->creds = ctx->client_creds;
- ctx->client_creds = GSS_C_NO_CREDENTIAL;
- client->updated = 1;
- return GSS_S_COMPLETE;
- }
-
- client->mech = NULL;
+ gss_buffer_desc ename;
- while (supported_mechs[i]->name != NULL) {
- if (supported_mechs[i]->oid.length == ctx->oid->length &&
- (memcmp(supported_mechs[i]->oid.elements,
- ctx->oid->elements, ctx->oid->length) == 0))
- client->mech = supported_mechs[i];
- i++;
- }
-
- if (client->mech == NULL)
- return GSS_S_FAILURE;
-
- if (ctx->client_creds &&
- (ctx->major = gss_inquire_cred_by_mech(&ctx->minor,
- ctx->client_creds, ctx->oid, &client->name, NULL, NULL, NULL))) {
+ if ((ctx->major = gss_display_name(&ctx->minor, ctx->client,
+ &client->displayname, NULL))) {
ssh_gssapi_error(ctx);
return (ctx->major);
}
- if ((ctx->major = gss_display_name(&ctx->minor, ctx->client,
- &client->displayname, NULL))) {
+ if ((ctx->major = gss_duplicate_name(&ctx->minor, ctx->client,
+ &client->name))) {
ssh_gssapi_error(ctx);
return (ctx->major);
}
void
ssh_gssapi_storecreds(void)
{
- if (gssapi_client.mech && gssapi_client.mech->storecreds) {
- (*gssapi_client.mech->storecreds)(&gssapi_client);
- } else
- debug("ssh_gssapi_storecreds: Not a GSSAPI mechanism");
+ OM_uint32 lmin;
+
+ gss_store_cred(&lmin, gssapi_client.creds,
+ GSS_C_INITIATE, GSS_C_NO_OID,
+ 1, 1, NULL, NULL);
}
/* This allows GSSAPI methods to do things to the childs environment based
ssh_gssapi_userok(char *user, struct passwd *pw)
{
OM_uint32 lmin;
+ int userok = 0;
if (gssapi_client.exportedname.length == 0 ||
gssapi_client.exportedname.value == NULL) {
debug("No suitable client data");
return 0;
}
- if (gssapi_client.mech && gssapi_client.mech->userok)
- if ((*gssapi_client.mech->userok)(&gssapi_client, user)) {
- gssapi_client.used = 1;
- gssapi_client.store.owner = pw;
- return 1;
- } else {
- /* Destroy delegated credentials if userok fails */
- gss_release_buffer(&lmin, &gssapi_client.displayname);
- gss_release_buffer(&lmin, &gssapi_client.exportedname);
- gss_release_cred(&lmin, &gssapi_client.creds);
- memset(&gssapi_client, 0, sizeof(ssh_gssapi_client));
- return 0;
- }
- else
- debug("ssh_gssapi_userok: Unknown GSSAPI mechanism");
- return (0);
+ if (GSS_ERROR(gss_userok(&lmin, gssapi_client.name, user, &userok)) ||
+ userok == 0) {
+ /* Destroy delegated credentials if userok fails */
+ gss_release_buffer(&lmin, &gssapi_client.displayname);
+ gss_release_buffer(&lmin, &gssapi_client.exportedname);
+ gss_release_name(&lmin, &gssapi_client.name);
+ gss_release_cred(&lmin, &gssapi_client.creds);
+ memset(&gssapi_client, 0, sizeof(ssh_gssapi_client));
+ return 0;
+ }
+
+ return (userok);
}
/* These bits are only used for rekeying. The unpriviledged child is running