diff options
Diffstat (limited to 'source4/heimdal/lib/gssapi/spnego/init_sec_context.c')
| -rw-r--r-- | source4/heimdal/lib/gssapi/spnego/init_sec_context.c | 668 |
1 files changed, 668 insertions, 0 deletions
diff --git a/source4/heimdal/lib/gssapi/spnego/init_sec_context.c b/source4/heimdal/lib/gssapi/spnego/init_sec_context.c new file mode 100644 index 0000000000..f032757fdd --- /dev/null +++ b/source4/heimdal/lib/gssapi/spnego/init_sec_context.c @@ -0,0 +1,668 @@ +/* + * Copyright (c) 1997 - 2004 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * Portions Copyright (c) 2004 PADL Software Pty Ltd. + * + * 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. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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. + */ + +#include "spnego/spnego_locl.h" + +RCSID("$Id$"); + +/* + * Is target_name an sane target for `mech´. + */ + +static OM_uint32 +initiator_approved(gss_name_t target_name, gss_OID mech) +{ + OM_uint32 min_stat, maj_stat; + gss_ctx_id_t ctx = GSS_C_NO_CONTEXT; + gss_buffer_desc out; + + maj_stat = gss_init_sec_context(&min_stat, + GSS_C_NO_CREDENTIAL, + &ctx, + target_name, + mech, + 0, + GSS_C_INDEFINITE, + GSS_C_NO_CHANNEL_BINDINGS, + GSS_C_NO_BUFFER, + NULL, + &out, + NULL, + NULL); + if (GSS_ERROR(maj_stat)) { + gss_mg_collect_error(mech, maj_stat, min_stat); + return GSS_S_BAD_MECH; + } + gss_release_buffer(&min_stat, &out); + gss_delete_sec_context(&min_stat, &ctx, NULL); + + return GSS_S_COMPLETE; +} + +/* + * Send a reply. Note that we only need to send a reply if we + * need to send a MIC or a mechanism token. Otherwise, we can + * return an empty buffer. + * + * The return value of this will be returned to the API, so it + * must return GSS_S_CONTINUE_NEEDED if a token was generated. + */ +static OM_uint32 +spnego_reply_internal(OM_uint32 *minor_status, + gssspnego_ctx context_handle, + const gss_buffer_t mech_buf, + gss_buffer_t mech_token, + gss_buffer_t output_token) +{ + NegotiationToken nt; + gss_buffer_desc mic_buf; + OM_uint32 ret; + size_t size; + + if (mech_buf == GSS_C_NO_BUFFER && mech_token->length == 0) { + output_token->length = 0; + output_token->value = NULL; + + return context_handle->open ? GSS_S_COMPLETE : GSS_S_FAILURE; + } + + memset(&nt, 0, sizeof(nt)); + + nt.element = choice_NegotiationToken_negTokenResp; + + ALLOC(nt.u.negTokenResp.negResult, 1); + if (nt.u.negTokenResp.negResult == NULL) { + *minor_status = ENOMEM; + return GSS_S_FAILURE; + } + + nt.u.negTokenResp.supportedMech = NULL; + + output_token->length = 0; + output_token->value = NULL; + + if (mech_token->length == 0) { + nt.u.negTokenResp.responseToken = NULL; + *(nt.u.negTokenResp.negResult) = accept_completed; + } else { + ALLOC(nt.u.negTokenResp.responseToken, 1); + if (nt.u.negTokenResp.responseToken == NULL) { + free_NegotiationToken(&nt); + *minor_status = ENOMEM; + return GSS_S_FAILURE; + } + nt.u.negTokenResp.responseToken->length = mech_token->length; + nt.u.negTokenResp.responseToken->data = mech_token->value; + mech_token->length = 0; + mech_token->value = NULL; + + *(nt.u.negTokenResp.negResult) = accept_incomplete; + } + + if (mech_buf != GSS_C_NO_BUFFER) { + + ret = gss_get_mic(minor_status, + context_handle->negotiated_ctx_id, + 0, + mech_buf, + &mic_buf); + if (ret == GSS_S_COMPLETE) { + ALLOC(nt.u.negTokenResp.mechListMIC, 1); + if (nt.u.negTokenResp.mechListMIC == NULL) { + gss_release_buffer(minor_status, &mic_buf); + free_NegotiationToken(&nt); + *minor_status = ENOMEM; + return GSS_S_FAILURE; + } + + nt.u.negTokenResp.mechListMIC->length = mic_buf.length; + nt.u.negTokenResp.mechListMIC->data = mic_buf.value; + } else if (ret == GSS_S_UNAVAILABLE) { + nt.u.negTokenResp.mechListMIC = NULL; + } if (ret) { + free_NegotiationToken(&nt); + *minor_status = ENOMEM; + return GSS_S_FAILURE; + } + } else { + nt.u.negTokenResp.mechListMIC = NULL; + } + + ASN1_MALLOC_ENCODE(NegotiationToken, + output_token->value, output_token->length, + &nt, &size, ret); + if (ret) { + free_NegotiationToken(&nt); + *minor_status = ret; + return GSS_S_FAILURE; + } + + if (*(nt.u.negTokenResp.negResult) == accept_completed) + ret = GSS_S_COMPLETE; + else + ret = GSS_S_CONTINUE_NEEDED; + + free_NegotiationToken(&nt); + return ret; +} + +static OM_uint32 +spnego_initial + (OM_uint32 * minor_status, + gssspnego_cred cred, + gss_ctx_id_t * context_handle, + const gss_name_t target_name, + const gss_OID mech_type, + OM_uint32 req_flags, + OM_uint32 time_req, + const gss_channel_bindings_t input_chan_bindings, + const gss_buffer_t input_token, + gss_OID * actual_mech_type, + gss_buffer_t output_token, + OM_uint32 * ret_flags, + OM_uint32 * time_rec + ) +{ + NegTokenInit ni; + int ret; + OM_uint32 sub, minor; + gss_buffer_desc mech_token; + u_char *buf; + size_t buf_size, buf_len; + gss_buffer_desc data; + size_t ni_len; + gss_ctx_id_t context; + gssspnego_ctx ctx; + spnego_name name = (spnego_name)target_name; + + *minor_status = 0; + + memset (&ni, 0, sizeof(ni)); + + *context_handle = GSS_C_NO_CONTEXT; + + if (target_name == GSS_C_NO_NAME) + return GSS_S_BAD_NAME; + + sub = _gss_spnego_alloc_sec_context(&minor, &context); + if (GSS_ERROR(sub)) { + *minor_status = minor; + return sub; + } + ctx = (gssspnego_ctx)context; + + HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); + + ctx->local = 1; + + sub = gss_import_name(&minor, &name->value, &name->type, &ctx->target_name); + if (GSS_ERROR(sub)) { + *minor_status = minor; + _gss_spnego_internal_delete_sec_context(&minor, &context, GSS_C_NO_BUFFER); + return sub; + } + + sub = _gss_spnego_indicate_mechtypelist(&minor, + ctx->target_name, + initiator_approved, + 0, + cred, + &ni.mechTypes, + &ctx->preferred_mech_type); + if (GSS_ERROR(sub)) { + *minor_status = minor; + _gss_spnego_internal_delete_sec_context(&minor, &context, GSS_C_NO_BUFFER); + return sub; + } + + ni.reqFlags = NULL; + + /* + * If we have a credential handle, use it to select the mechanism + * that we will use + */ + + /* generate optimistic token */ + sub = gss_init_sec_context(&minor, + (cred != NULL) ? cred->negotiated_cred_id : + GSS_C_NO_CREDENTIAL, + &ctx->negotiated_ctx_id, + ctx->target_name, + ctx->preferred_mech_type, + req_flags, + time_req, + input_chan_bindings, + input_token, + &ctx->negotiated_mech_type, + &mech_token, + &ctx->mech_flags, + &ctx->mech_time_rec); + if (GSS_ERROR(sub)) { + free_NegTokenInit(&ni); + *minor_status = minor; + gss_mg_collect_error(ctx->preferred_mech_type, sub, minor); + _gss_spnego_internal_delete_sec_context(&minor, &context, GSS_C_NO_BUFFER); + return sub; + } + if (sub == GSS_S_COMPLETE) + ctx->maybe_open = 1; + + if (mech_token.length != 0) { + ALLOC(ni.mechToken, 1); + if (ni.mechToken == NULL) { + free_NegTokenInit(&ni); + gss_release_buffer(&minor, &mech_token); + _gss_spnego_internal_delete_sec_context(&minor, &context, GSS_C_NO_BUFFER); + *minor_status = ENOMEM; + return GSS_S_FAILURE; + } + ni.mechToken->length = mech_token.length; + ni.mechToken->data = malloc(mech_token.length); + if (ni.mechToken->data == NULL && mech_token.length != 0) { + free_NegTokenInit(&ni); + gss_release_buffer(&minor, &mech_token); + *minor_status = ENOMEM; + _gss_spnego_internal_delete_sec_context(&minor, &context, GSS_C_NO_BUFFER); + return GSS_S_FAILURE; + } + memcpy(ni.mechToken->data, mech_token.value, mech_token.length); + gss_release_buffer(&minor, &mech_token); + } else + ni.mechToken = NULL; + + ni.mechListMIC = NULL; + + ni_len = length_NegTokenInit(&ni); + buf_size = 1 + der_length_len(ni_len) + ni_len; + + buf = malloc(buf_size); + if (buf == NULL) { + free_NegTokenInit(&ni); + *minor_status = ENOMEM; + _gss_spnego_internal_delete_sec_context(&minor, &context, GSS_C_NO_BUFFER); + return GSS_S_FAILURE; + } + + ret = encode_NegTokenInit(buf + buf_size - 1, + ni_len, + &ni, &buf_len); + if (ret == 0 && ni_len != buf_len) + abort(); + + if (ret == 0) { + size_t tmp; + + ret = der_put_length_and_tag(buf + buf_size - buf_len - 1, + buf_size - buf_len, + buf_len, + ASN1_C_CONTEXT, + CONS, + 0, + &tmp); + if (ret == 0 && tmp + buf_len != buf_size) + abort(); + } + if (ret) { + *minor_status = ret; + free(buf); + free_NegTokenInit(&ni); + _gss_spnego_internal_delete_sec_context(&minor, &context, GSS_C_NO_BUFFER); + return GSS_S_FAILURE; + } + + data.value = buf; + data.length = buf_size; + + ctx->initiator_mech_types.len = ni.mechTypes.len; + ctx->initiator_mech_types.val = ni.mechTypes.val; + ni.mechTypes.len = 0; + ni.mechTypes.val = NULL; + + free_NegTokenInit(&ni); + + sub = gss_encapsulate_token(&data, + GSS_SPNEGO_MECHANISM, + output_token); + free (buf); + + if (sub) { + _gss_spnego_internal_delete_sec_context(&minor, &context, GSS_C_NO_BUFFER); + return sub; + } + + if (actual_mech_type) + *actual_mech_type = ctx->negotiated_mech_type; + if (ret_flags) + *ret_flags = ctx->mech_flags; + if (time_rec) + *time_rec = ctx->mech_time_rec; + + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + + *context_handle = context; + + return GSS_S_CONTINUE_NEEDED; +} + +static OM_uint32 +spnego_reply + (OM_uint32 * minor_status, + const gssspnego_cred cred, + gss_ctx_id_t * context_handle, + const gss_name_t target_name, + const gss_OID mech_type, + OM_uint32 req_flags, + OM_uint32 time_req, + const gss_channel_bindings_t input_chan_bindings, + const gss_buffer_t input_token, + gss_OID * actual_mech_type, + gss_buffer_t output_token, + OM_uint32 * ret_flags, + OM_uint32 * time_rec + ) +{ + OM_uint32 ret, minor; + NegTokenResp resp; + size_t len, taglen; + gss_OID_desc mech; + int require_mic; + size_t buf_len; + gss_buffer_desc mic_buf, mech_buf; + gss_buffer_desc mech_output_token; + gssspnego_ctx ctx; + + *minor_status = 0; + + ctx = (gssspnego_ctx)*context_handle; + + output_token->length = 0; + output_token->value = NULL; + + mech_output_token.length = 0; + mech_output_token.value = NULL; + + mech_buf.value = NULL; + mech_buf.length = 0; + + ret = der_match_tag_and_length(input_token->value, input_token->length, + ASN1_C_CONTEXT, CONS, 1, &len, &taglen); + if (ret) + return ret; + + if (len > input_token->length - taglen) + return ASN1_OVERRUN; + + ret = decode_NegTokenResp((const unsigned char *)input_token->value+taglen, + len, &resp, NULL); + if (ret) { + *minor_status = ENOMEM; + return GSS_S_FAILURE; + } + + if (resp.negResult == NULL + || *(resp.negResult) == reject + /* || resp.supportedMech == NULL */ + ) + { + free_NegTokenResp(&resp); + return GSS_S_BAD_MECH; + } + + /* + * Pick up the mechanism that the acceptor selected, only allow it + * to be sent in packet. + */ + + HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); + + if (resp.supportedMech) { + + if (ctx->oidlen) { + free_NegTokenResp(&resp); + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + return GSS_S_BAD_MECH; + } + ret = der_put_oid(ctx->oidbuf + sizeof(ctx->oidbuf) - 1, + sizeof(ctx->oidbuf), + resp.supportedMech, + &ctx->oidlen); + /* Avoid recursively embedded SPNEGO */ + if (ret || (ctx->oidlen == GSS_SPNEGO_MECHANISM->length && + memcmp(ctx->oidbuf + sizeof(ctx->oidbuf) - ctx->oidlen, + GSS_SPNEGO_MECHANISM->elements, + ctx->oidlen) == 0)) + { + free_NegTokenResp(&resp); + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + return GSS_S_BAD_MECH; + } + + /* check if the acceptor took our optimistic token */ + if (ctx->oidlen != ctx->preferred_mech_type->length || + memcmp(ctx->oidbuf + sizeof(ctx->oidbuf) - ctx->oidlen, + ctx->preferred_mech_type->elements, + ctx->oidlen) != 0) + { + gss_delete_sec_context(&minor, &ctx->negotiated_ctx_id, + GSS_C_NO_BUFFER); + ctx->negotiated_ctx_id = GSS_C_NO_CONTEXT; + } + } else if (ctx->oidlen == 0) { + free_NegTokenResp(&resp); + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + return GSS_S_BAD_MECH; + } + + /* if a token (of non zero length), or no context, pass to underlaying mech */ + if ((resp.responseToken != NULL && resp.responseToken->length) || + ctx->negotiated_ctx_id == GSS_C_NO_CONTEXT) { + gss_buffer_desc mech_input_token; + + if (resp.responseToken) { + mech_input_token.length = resp.responseToken->length; + mech_input_token.value = resp.responseToken->data; + } else { + mech_input_token.length = 0; + mech_input_token.value = NULL; + } + + + mech.length = ctx->oidlen; + mech.elements = ctx->oidbuf + sizeof(ctx->oidbuf) - ctx->oidlen; + + /* Fall through as if the negotiated mechanism + was requested explicitly */ + ret = gss_init_sec_context(&minor, + (cred != NULL) ? cred->negotiated_cred_id : + GSS_C_NO_CREDENTIAL, + &ctx->negotiated_ctx_id, + ctx->target_name, + &mech, + req_flags, + time_req, + input_chan_bindings, + &mech_input_token, + &ctx->negotiated_mech_type, + &mech_output_token, + &ctx->mech_flags, + &ctx->mech_time_rec); + if (GSS_ERROR(ret)) { + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + free_NegTokenResp(&resp); + gss_mg_collect_error(&mech, ret, minor); + *minor_status = minor; + return ret; + } + if (ret == GSS_S_COMPLETE) { + ctx->open = 1; + } + } else if (*(resp.negResult) == accept_completed) { + if (ctx->maybe_open) + ctx->open = 1; + } + + if (*(resp.negResult) == request_mic) { + ctx->require_mic = 1; + } + + if (ctx->open) { + /* + * Verify the mechListMIC if one was provided or CFX was + * used and a non-preferred mechanism was selected + */ + if (resp.mechListMIC != NULL) { + require_mic = 1; + } else { + ret = _gss_spnego_require_mechlist_mic(minor_status, ctx, + &require_mic); + if (ret) { + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + free_NegTokenResp(&resp); + gss_release_buffer(&minor, &mech_output_token); + return ret; + } + } + } else { + require_mic = 0; + } + + if (require_mic) { + ASN1_MALLOC_ENCODE(MechTypeList, mech_buf.value, mech_buf.length, + &ctx->initiator_mech_types, &buf_len, ret); + if (ret) { + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + free_NegTokenResp(&resp); + gss_release_buffer(&minor, &mech_output_token); + *minor_status = ret; + return GSS_S_FAILURE; + } + if (mech_buf.length != buf_len) + abort(); + + if (resp.mechListMIC == NULL) { + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + free(mech_buf.value); + free_NegTokenResp(&resp); + *minor_status = 0; + return GSS_S_DEFECTIVE_TOKEN; + } + mic_buf.length = resp.mechListMIC->length; + mic_buf.value = resp.mechListMIC->data; + + if (mech_output_token.length == 0) { + ret = gss_verify_mic(minor_status, + ctx->negotiated_ctx_id, + &mech_buf, + &mic_buf, + NULL); + if (ret) { + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + free(mech_buf.value); + gss_release_buffer(&minor, &mech_output_token); + free_NegTokenResp(&resp); + return GSS_S_DEFECTIVE_TOKEN; + } + ctx->verified_mic = 1; + } + } + + ret = spnego_reply_internal(minor_status, ctx, + require_mic ? &mech_buf : NULL, + &mech_output_token, + output_token); + + if (mech_buf.value != NULL) + free(mech_buf.value); + + free_NegTokenResp(&resp); + gss_release_buffer(&minor, &mech_output_token); + + if (actual_mech_type) + *actual_mech_type = ctx->negotiated_mech_type; + if (ret_flags) + *ret_flags = ctx->mech_flags; + if (time_rec) + *time_rec = ctx->mech_time_rec; + + HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); + return ret; +} + +OM_uint32 _gss_spnego_init_sec_context + (OM_uint32 * minor_status, + const gss_cred_id_t initiator_cred_handle, + gss_ctx_id_t * context_handle, + const gss_name_t target_name, + const gss_OID mech_type, + OM_uint32 req_flags, + OM_uint32 time_req, + const gss_channel_bindings_t input_chan_bindings, + const gss_buffer_t input_token, + gss_OID * actual_mech_type, + gss_buffer_t output_token, + OM_uint32 * ret_flags, + OM_uint32 * time_rec + ) +{ + gssspnego_cred cred = (gssspnego_cred)initiator_cred_handle; + + if (*context_handle == GSS_C_NO_CONTEXT) + return spnego_initial (minor_status, + cred, + context_handle, + target_name, + mech_type, + req_flags, + time_req, + input_chan_bindings, + input_token, + actual_mech_type, + output_token, + ret_flags, + time_rec); + else + return spnego_reply (minor_status, + cred, + context_handle, + target_name, + mech_type, + req_flags, + time_req, + input_chan_bindings, + input_token, + actual_mech_type, + output_token, + ret_flags, + time_rec); +} + |