freebsd-dev/lib/libgssapi/gss_accept_sec_context.c
Doug Rabson c0b9f4fe65 Add a new extensible GSS-API layer which can support GSS-API plugins,
similar the the Solaris implementation. Repackage the krb5 GSS mechanism
as a plugin library for the new implementation. This also includes a
comprehensive set of manpages for the GSS-API functions with text mostly
taken from the RFC.

Reviewed by: Love Hörnquist Åstrand <lha@it.su.se>, ru (build system), des (openssh parts)
2005-12-29 14:40:22 +00:00

222 lines
5.8 KiB
C

/*-
* Copyright (c) 2005 Doug Rabson
* 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
*
* $FreeBSD$
*/
#include <gssapi/gssapi.h>
#include <stdlib.h>
#include <errno.h>
#include "mech_switch.h"
#include "context.h"
#include "cred.h"
#include "name.h"
OM_uint32 gss_accept_sec_context(OM_uint32 *minor_status,
gss_ctx_id_t *context_handle,
const gss_cred_id_t acceptor_cred_handle,
const gss_buffer_t input_token,
const gss_channel_bindings_t input_chan_bindings,
gss_name_t *src_name,
gss_OID *mech_type,
gss_buffer_t output_token,
OM_uint32 *ret_flags,
OM_uint32 *time_rec,
gss_cred_id_t *delegated_cred_handle)
{
OM_uint32 major_status;
struct _gss_mech_switch *m;
struct _gss_context *ctx = (struct _gss_context *) *context_handle;
struct _gss_cred *cred = (struct _gss_cred *) acceptor_cred_handle;
struct _gss_mechanism_cred *mc;
gss_cred_id_t acceptor_mc, delegated_mc;
gss_name_t src_mn;
int allocated_ctx;
*minor_status = 0;
if (src_name) *src_name = 0;
if (mech_type) *mech_type = 0;
if (ret_flags) *ret_flags = 0;
if (time_rec) *time_rec = 0;
if (delegated_cred_handle) *delegated_cred_handle = 0;
output_token->length = 0;
output_token->value = 0;
/*
* If this is the first call (*context_handle is NULL), we must
* parse the input token to figure out the mechanism to use.
*/
if (*context_handle == GSS_C_NO_CONTEXT) {
unsigned char *p = input_token->value;
size_t len = input_token->length;
size_t a, b;
gss_OID_desc mech_oid;
/*
* Token must start with [APPLICATION 0] SEQUENCE.
*/
if (len == 0 || *p != 0x60)
return (GSS_S_DEFECTIVE_TOKEN);
p++;
len--;
/*
* Decode the length and make sure it agrees with the
* token length.
*/
if (len == 0)
return (GSS_S_DEFECTIVE_TOKEN);
if ((*p & 0x80) == 0) {
a = *p;
p++;
len--;
} else {
b = *p & 0x7f;
p++;
len--;
if (len < b)
return (GSS_S_DEFECTIVE_TOKEN);
a = 0;
while (b) {
a = (a << 8) | *p;
p++;
len--;
b--;
}
}
if (a != len)
return (GSS_S_DEFECTIVE_TOKEN);
/*
* Decode the OID for the mechanism. Simplify life by
* assuming that the OID length is less than 128 bytes.
*/
if (len < 2 || *p != 0x06)
return (GSS_S_DEFECTIVE_TOKEN);
if ((p[1] & 0x80) || p[1] > (len - 2))
return (GSS_S_DEFECTIVE_TOKEN);
mech_oid.length = p[1];
p += 2;
len -= 2;
mech_oid.elements = p;
/*
* Now that we have a mechanism, we can find the
* implementation.
*/
ctx = malloc(sizeof(struct _gss_context));
if (!ctx) {
*minor_status = ENOMEM;
return (GSS_S_DEFECTIVE_TOKEN);
}
memset(ctx, 0, sizeof(struct _gss_context));
m = ctx->gc_mech = _gss_find_mech_switch(&mech_oid);
if (!m) {
free(ctx);
return (GSS_S_BAD_MECH);
}
allocated_ctx = 1;
} else {
m = ctx->gc_mech;
allocated_ctx = 0;
}
if (cred) {
SLIST_FOREACH(mc, &cred->gc_mc, gmc_link)
if (mc->gmc_mech == m)
break;
if (!mc)
return (GSS_S_BAD_MECH);
acceptor_mc = mc->gmc_cred;
} else {
acceptor_mc = GSS_C_NO_CREDENTIAL;
}
delegated_mc = GSS_C_NO_CREDENTIAL;
major_status = m->gm_accept_sec_context(minor_status,
&ctx->gc_ctx,
acceptor_mc,
input_token,
input_chan_bindings,
&src_mn,
mech_type,
output_token,
ret_flags,
time_rec,
&delegated_mc);
if (major_status != GSS_S_COMPLETE &&
major_status != GSS_S_CONTINUE_NEEDED)
return (major_status);
if (!src_name) {
m->gm_release_name(minor_status, &src_mn);
} else {
/*
* Make a new name and mark it as an MN.
*/
struct _gss_name *name = _gss_make_name(m, src_mn);
if (!name) {
m->gm_release_name(minor_status, &src_mn);
return (GSS_S_FAILURE);
}
*src_name = (gss_name_t) name;
}
if (*ret_flags & GSS_C_DELEG_FLAG) {
if (!delegated_cred_handle) {
m->gm_release_cred(minor_status, &delegated_mc);
*ret_flags &= ~GSS_C_DELEG_FLAG;
} else {
struct _gss_cred *cred;
struct _gss_mechanism_cred *mc;
cred = malloc(sizeof(struct _gss_cred));
if (!cred) {
*minor_status = ENOMEM;
return (GSS_S_FAILURE);
}
mc = malloc(sizeof(struct _gss_mechanism_cred));
if (!mc) {
free(cred);
*minor_status = ENOMEM;
return (GSS_S_FAILURE);
}
m->gm_inquire_cred(minor_status, delegated_mc,
0, 0, &cred->gc_usage, 0);
mc->gmc_mech = m;
mc->gmc_mech_oid = &m->gm_mech_oid;
mc->gmc_cred = delegated_mc;
SLIST_INSERT_HEAD(&cred->gc_mc, mc, gmc_link);
*delegated_cred_handle = (gss_cred_id_t) cred;
}
}
*context_handle = (gss_ctx_id_t) ctx;
return (major_status);
}