/* * 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: accept_sec_context.c,v 1.6 2006/10/07 22:26:57 lha Exp $"); OM_uint32 _gss_spnego_encode_response(OM_uint32 *minor_status, const NegTokenResp *resp, gss_buffer_t data, u_char **ret_buf) { OM_uint32 ret; u_char *buf; size_t buf_size, buf_len; buf_size = 1024; buf = malloc(buf_size); if (buf == NULL) { *minor_status = ENOMEM; return GSS_S_FAILURE; } do { ret = encode_NegTokenResp(buf + buf_size - 1, buf_size, resp, &buf_len); 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, 1, &tmp); if (ret == 0) buf_len += tmp; } if (ret) { if (ret == ASN1_OVERFLOW) { u_char *tmp; buf_size *= 2; tmp = realloc (buf, buf_size); if (tmp == NULL) { *minor_status = ENOMEM; free(buf); return GSS_S_FAILURE; } buf = tmp; } else { *minor_status = ret; free(buf); return GSS_S_FAILURE; } } } while (ret == ASN1_OVERFLOW); data->value = buf + buf_size - buf_len; data->length = buf_len; *ret_buf = buf; return GSS_S_COMPLETE; } static OM_uint32 send_reject (OM_uint32 *minor_status, gss_buffer_t output_token) { NegTokenResp resp; gss_buffer_desc data; u_char *buf; OM_uint32 ret; ALLOC(resp.negResult, 1); if (resp.negResult == NULL) { *minor_status = ENOMEM; return GSS_S_FAILURE; } *(resp.negResult) = reject; resp.supportedMech = NULL; resp.responseToken = NULL; resp.mechListMIC = NULL; ret = _gss_spnego_encode_response (minor_status, &resp, &data, &buf); free_NegTokenResp(&resp); if (ret != GSS_S_COMPLETE) return ret; output_token->value = malloc(data.length); if (output_token->value == NULL) { *minor_status = ENOMEM; ret = GSS_S_FAILURE; } else { output_token->length = data.length; memcpy(output_token->value, data.value, output_token->length); } free(buf); if (ret != GSS_S_COMPLETE) return ret; return GSS_S_BAD_MECH; } OM_uint32 _gss_spnego_indicate_mechtypelist (OM_uint32 *minor_status, int includeMSCompatOID, const gssspnego_cred cred_handle, MechTypeList *mechtypelist, gss_OID *preferred_mech) { OM_uint32 ret; gss_OID_set supported_mechs = GSS_C_NO_OID_SET; int i, count; if (cred_handle != NULL) { ret = gss_inquire_cred(minor_status, cred_handle->negotiated_cred_id, NULL, NULL, NULL, &supported_mechs); } else { ret = gss_indicate_mechs(minor_status, &supported_mechs); } if (ret != GSS_S_COMPLETE) { return ret; } if (supported_mechs->count == 0) { *minor_status = ENOENT; gss_release_oid_set(minor_status, &supported_mechs); return GSS_S_FAILURE; } count = supported_mechs->count; if (includeMSCompatOID) count++; mechtypelist->len = 0; mechtypelist->val = calloc(count, sizeof(MechType)); if (mechtypelist->val == NULL) { *minor_status = ENOMEM; gss_release_oid_set(minor_status, &supported_mechs); return GSS_S_FAILURE; } for (i = 0; i < supported_mechs->count; i++) { ret = _gss_spnego_add_mech_type(&supported_mechs->elements[i], includeMSCompatOID, mechtypelist); if (ret != 0) { *minor_status = ENOMEM; ret = GSS_S_FAILURE; break; } } if (ret == GSS_S_COMPLETE && preferred_mech != NULL) { ret = gss_duplicate_oid(minor_status, &supported_mechs->elements[0], preferred_mech); } if (ret != GSS_S_COMPLETE) { free_MechTypeList(mechtypelist); mechtypelist->len = 0; mechtypelist->val = NULL; } gss_release_oid_set(minor_status, &supported_mechs); return ret; } static OM_uint32 send_supported_mechs (OM_uint32 *minor_status, gss_buffer_t output_token) { NegTokenInit ni; char hostname[MAXHOSTNAMELEN], *p; gss_buffer_desc name_buf; gss_OID name_type; gss_name_t target_princ; gss_name_t canon_princ; OM_uint32 ret, minor; u_char *buf; size_t buf_size, buf_len; gss_buffer_desc data; memset(&ni, 0, sizeof(ni)); ni.reqFlags = NULL; ni.mechToken = NULL; ni.negHints = NULL; ni.mechListMIC = NULL; ret = _gss_spnego_indicate_mechtypelist(minor_status, 1, NULL, &ni.mechTypes, NULL); if (ret != GSS_S_COMPLETE) { return ret; } memset(&target_princ, 0, sizeof(target_princ)); if (gethostname(hostname, sizeof(hostname) - 1) != 0) { *minor_status = errno; free_NegTokenInit(&ni); return GSS_S_FAILURE; } /* Send the constructed SAM name for this host */ for (p = hostname; *p != '\0' && *p != '.'; p++) { *p = toupper((unsigned char)*p); } *p++ = '$'; *p = '\0'; name_buf.length = strlen(hostname); name_buf.value = hostname; ret = gss_import_name(minor_status, &name_buf, GSS_C_NO_OID, &target_princ); if (ret != GSS_S_COMPLETE) { return ret; } name_buf.length = 0; name_buf.value = NULL; /* Canonicalize the name using the preferred mechanism */ ret = gss_canonicalize_name(minor_status, target_princ, GSS_C_NO_OID, &canon_princ); if (ret != GSS_S_COMPLETE) { gss_release_name(&minor, &target_princ); return ret; } ret = gss_display_name(minor_status, canon_princ, &name_buf, &name_type); if (ret != GSS_S_COMPLETE) { gss_release_name(&minor, &canon_princ); gss_release_name(&minor, &target_princ); return ret; } gss_release_name(&minor, &canon_princ); gss_release_name(&minor, &target_princ); ALLOC(ni.negHints, 1); if (ni.negHints == NULL) { *minor_status = ENOMEM; gss_release_buffer(&minor, &name_buf); free_NegTokenInit(&ni); return GSS_S_FAILURE; } ALLOC(ni.negHints->hintName, 1); if (ni.negHints->hintName == NULL) { *minor_status = ENOMEM; gss_release_buffer(&minor, &name_buf); free_NegTokenInit(&ni); return GSS_S_FAILURE; } *(ni.negHints->hintName) = name_buf.value; name_buf.value = NULL; ni.negHints->hintAddress = NULL; buf_size = 1024; buf = malloc(buf_size); if (buf == NULL) { free_NegTokenInit(&ni); *minor_status = ENOMEM; return GSS_S_FAILURE; } do { ret = encode_NegTokenInit(buf + buf_size - 1, buf_size, &ni, &buf_len); 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) buf_len += tmp; } if (ret) { if (ret == ASN1_OVERFLOW) { u_char *tmp; buf_size *= 2; tmp = realloc (buf, buf_size); if (tmp == NULL) { *minor_status = ENOMEM; free(buf); free_NegTokenInit(&ni); return GSS_S_FAILURE; } buf = tmp; } else { *minor_status = ret; free(buf); free_NegTokenInit(&ni); return GSS_S_FAILURE; } } } while (ret == ASN1_OVERFLOW); data.value = buf + buf_size - buf_len; data.length = buf_len; ret = gss_encapsulate_token(&data, GSS_SPNEGO_MECHANISM, output_token); free (buf); free_NegTokenInit (&ni); if (ret != GSS_S_COMPLETE) return ret; *minor_status = 0; return GSS_S_CONTINUE_NEEDED; } static OM_uint32 send_accept (OM_uint32 *minor_status, gssspnego_ctx context_handle, gss_buffer_t mech_token, int initial_response, gss_buffer_t mech_buf, gss_buffer_t output_token) { NegTokenResp resp; gss_buffer_desc data; u_char *buf; OM_uint32 ret; gss_buffer_desc mech_mic_buf; memset(&resp, 0, sizeof(resp)); ALLOC(resp.negResult, 1); if (resp.negResult == NULL) { *minor_status = ENOMEM; return GSS_S_FAILURE; } if (context_handle->open) { if (mech_token != GSS_C_NO_BUFFER && mech_token->length != 0 && mech_buf != GSS_C_NO_BUFFER) *(resp.negResult) = accept_incomplete; else *(resp.negResult) = accept_completed; } else { if (initial_response && context_handle->require_mic) *(resp.negResult) = request_mic; else *(resp.negResult) = accept_incomplete; } if (initial_response) { ALLOC(resp.supportedMech, 1); if (resp.supportedMech == NULL) { free_NegTokenResp(&resp); *minor_status = ENOMEM; return GSS_S_FAILURE; } ret = der_get_oid(context_handle->preferred_mech_type->elements, context_handle->preferred_mech_type->length, resp.supportedMech, NULL); if (ret) { free_NegTokenResp(&resp); *minor_status = ENOMEM; return GSS_S_FAILURE; } } else { resp.supportedMech = NULL; } if (mech_token != GSS_C_NO_BUFFER && mech_token->length != 0) { ALLOC(resp.responseToken, 1); if (resp.responseToken == NULL) { free_NegTokenResp(&resp); *minor_status = ENOMEM; return GSS_S_FAILURE; } resp.responseToken->length = mech_token->length; resp.responseToken->data = mech_token->value; mech_token->length = 0; mech_token->value = NULL; } else { resp.responseToken = NULL; } if (mech_buf != GSS_C_NO_BUFFER) { ALLOC(resp.mechListMIC, 1); if (resp.mechListMIC == NULL) { free_NegTokenResp(&resp); *minor_status = ENOMEM; return GSS_S_FAILURE; } ret = gss_get_mic(minor_status, context_handle->negotiated_ctx_id, 0, mech_buf, &mech_mic_buf); if (ret != GSS_S_COMPLETE) { free_NegTokenResp(&resp); return ret; } resp.mechListMIC->length = mech_mic_buf.length; resp.mechListMIC->data = mech_mic_buf.value; } else resp.mechListMIC = NULL; ret = _gss_spnego_encode_response (minor_status, &resp, &data, &buf); if (ret != GSS_S_COMPLETE) { free_NegTokenResp(&resp); return ret; } /* * The response should not be encapsulated, because * it is a SubsequentContextToken (note though RFC 1964 * specifies encapsulation for all _Kerberos_ tokens). */ output_token->value = malloc(data.length); if (output_token->value == NULL) { *minor_status = ENOMEM; ret = GSS_S_FAILURE; } else { output_token->length = data.length; memcpy(output_token->value, data.value, output_token->length); } free(buf); if (ret != GSS_S_COMPLETE) { free_NegTokenResp(&resp); return ret; } ret = (*(resp.negResult) == accept_completed) ? GSS_S_COMPLETE : GSS_S_CONTINUE_NEEDED; free_NegTokenResp(&resp); return ret; } static OM_uint32 verify_mechlist_mic (OM_uint32 *minor_status, gssspnego_ctx context_handle, gss_buffer_t mech_buf, heim_octet_string *mechListMIC ) { OM_uint32 ret; gss_buffer_desc mic_buf; if (context_handle->verified_mic) { /* This doesn't make sense, we've already verified it? */ *minor_status = 0; return GSS_S_DUPLICATE_TOKEN; } if (mechListMIC == NULL) { *minor_status = 0; return GSS_S_DEFECTIVE_TOKEN; } mic_buf.length = mechListMIC->length; mic_buf.value = mechListMIC->data; ret = gss_verify_mic(minor_status, context_handle->negotiated_ctx_id, mech_buf, &mic_buf, NULL); if (ret != GSS_S_COMPLETE) ret = GSS_S_DEFECTIVE_TOKEN; return ret; } OM_uint32 _gss_spnego_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_buffer, 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 ret, ret2, minor; NegTokenInit ni; NegTokenResp na; size_t ni_len, na_len; int i; gss_buffer_desc data; size_t len, taglen; int initialToken; unsigned int negResult = accept_incomplete; gss_buffer_t mech_input_token = GSS_C_NO_BUFFER; gss_buffer_t mech_output_token = GSS_C_NO_BUFFER; gss_buffer_desc mech_buf; gss_OID preferred_mech_type = GSS_C_NO_OID; gssspnego_ctx ctx; gssspnego_cred acceptor_cred = (gssspnego_cred)acceptor_cred_handle; *minor_status = 0; output_token->length = 0; output_token->value = NULL; if (src_name != NULL) *src_name = GSS_C_NO_NAME; if (mech_type != NULL) *mech_type = GSS_C_NO_OID; if (ret_flags != NULL) *ret_flags = 0; if (time_rec != NULL) *time_rec = 0; if (delegated_cred_handle != NULL) *delegated_cred_handle = GSS_C_NO_CREDENTIAL; mech_buf.value = NULL; if (*context_handle == GSS_C_NO_CONTEXT) { ret = _gss_spnego_alloc_sec_context(minor_status, context_handle); if (ret != GSS_S_COMPLETE) return ret; if (input_token_buffer->length == 0) { return send_supported_mechs (minor_status, output_token); } } ctx = (gssspnego_ctx)*context_handle; /* * The GSS-API encapsulation is only present on the initial * context token (negTokenInit). */ ret = gss_decapsulate_token (input_token_buffer, GSS_SPNEGO_MECHANISM, &data); initialToken = (ret == GSS_S_COMPLETE); if (!initialToken) { data.value = input_token_buffer->value; data.length = input_token_buffer->length; } ret = der_match_tag_and_length(data.value, data.length, ASN1_C_CONTEXT, CONS, initialToken ? 0 : 1, &len, &taglen); if (ret) { *minor_status = ret; return GSS_S_FAILURE; } if (len > data.length - taglen) { *minor_status = ASN1_OVERRUN; return GSS_S_FAILURE; } if (initialToken) { ret = decode_NegTokenInit((const unsigned char *)data.value + taglen, len, &ni, &ni_len); } else { ret = decode_NegTokenResp((const unsigned char *)data.value + taglen, len, &na, &na_len); } if (ret) { *minor_status = ret; return GSS_S_DEFECTIVE_TOKEN; } if (!initialToken && na.negResult != NULL) { negResult = *(na.negResult); } if (negResult == reject || negResult == request_mic) { /* request_mic should only be sent by acceptor */ free_NegTokenResp(&na); return GSS_S_DEFECTIVE_TOKEN; } if (initialToken) { for (i = 0; i < ni.mechTypes.len; ++i) { /* Call glue layer to find first mech we support */ ret = _gss_spnego_select_mech(minor_status, &ni.mechTypes.val[i], &preferred_mech_type); if (ret == 0) break; } if (preferred_mech_type == GSS_C_NO_OID) { free_NegTokenInit(&ni); return GSS_S_BAD_MECH; } } HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex); if (initialToken) { ctx->preferred_mech_type = preferred_mech_type; ctx->initiator_mech_types.len = ni.mechTypes.len; ctx->initiator_mech_types.val = ni.mechTypes.val; ni.mechTypes.len = 0; ni.mechTypes.val = NULL; } { gss_buffer_desc ibuf, obuf; int require_mic, verify_mic, get_mic; int require_response; heim_octet_string *mic; if (initialToken) { if (ni.mechToken != NULL) { ibuf.length = ni.mechToken->length; ibuf.value = ni.mechToken->data; mech_input_token = &ibuf; } } else { if (na.responseToken != NULL) { ibuf.length = na.responseToken->length; ibuf.value = na.responseToken->data; mech_input_token = &ibuf; } } if (mech_input_token != GSS_C_NO_BUFFER) { gss_cred_id_t mech_cred; gss_cred_id_t mech_delegated_cred; gss_cred_id_t *mech_delegated_cred_p; if (acceptor_cred != NULL) mech_cred = acceptor_cred->negotiated_cred_id; else mech_cred = GSS_C_NO_CREDENTIAL; if (delegated_cred_handle != NULL) { mech_delegated_cred = GSS_C_NO_CREDENTIAL; mech_delegated_cred_p = &mech_delegated_cred; } else { mech_delegated_cred_p = NULL; } if (ctx->mech_src_name != GSS_C_NO_NAME) gss_release_name(&minor, &ctx->mech_src_name); if (ctx->delegated_cred_id != GSS_C_NO_CREDENTIAL) _gss_spnego_release_cred(&minor, &ctx->delegated_cred_id); ret = gss_accept_sec_context(&minor, &ctx->negotiated_ctx_id, mech_cred, mech_input_token, input_chan_bindings, &ctx->mech_src_name, &ctx->negotiated_mech_type, &obuf, &ctx->mech_flags, &ctx->mech_time_rec, mech_delegated_cred_p); if (ret == GSS_S_COMPLETE || ret == GSS_S_CONTINUE_NEEDED) { if (mech_delegated_cred_p != NULL && mech_delegated_cred != GSS_C_NO_CREDENTIAL) { ret2 = _gss_spnego_alloc_cred(minor_status, mech_delegated_cred, &ctx->delegated_cred_id); if (ret2 != GSS_S_COMPLETE) ret = ret2; } mech_output_token = &obuf; } if (ret != GSS_S_COMPLETE && ret != GSS_S_CONTINUE_NEEDED) { if (initialToken) free_NegTokenInit(&ni); else free_NegTokenResp(&na); send_reject (minor_status, output_token); HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); return ret; } if (ret == GSS_S_COMPLETE) ctx->open = 1; } else ret = GSS_S_COMPLETE; ret2 = _gss_spnego_require_mechlist_mic(minor_status, ctx, &require_mic); if (ret2) goto out; ctx->require_mic = require_mic; mic = initialToken ? ni.mechListMIC : na.mechListMIC; if (mic != NULL) require_mic = 1; if (ctx->open && require_mic) { if (mech_input_token == GSS_C_NO_BUFFER) { /* Even/One */ verify_mic = 1; get_mic = 0; } else if (mech_output_token != GSS_C_NO_BUFFER && mech_output_token->length == 0) { /* Odd */ get_mic = verify_mic = 1; } else { /* Even/One */ verify_mic = 0; get_mic = 1; } if (verify_mic || get_mic) { int eret; size_t buf_len; ASN1_MALLOC_ENCODE(MechTypeList, mech_buf.value, mech_buf.length, &ctx->initiator_mech_types, &buf_len, eret); if (eret) { ret2 = GSS_S_FAILURE; *minor_status = eret; goto out; } if (mech_buf.length != buf_len) abort(); } if (verify_mic) { ret2 = verify_mechlist_mic(minor_status, ctx, &mech_buf, mic); if (ret2) { if (get_mic) send_reject (minor_status, output_token); goto out; } ctx->verified_mic = 1; } } else verify_mic = get_mic = 0; if (ctx->mech_flags & GSS_C_DCE_STYLE) require_response = (negResult != accept_completed); else require_response = 0; /* * Check whether we need to send a result: there should be only * one accept_completed response sent in the entire negotiation */ if ((mech_output_token != GSS_C_NO_BUFFER && mech_output_token->length != 0) || require_response || get_mic) { ret2 = send_accept (minor_status, ctx, mech_output_token, initialToken, get_mic ? &mech_buf : NULL, output_token); if (ret2) goto out; } out: if (ret2 != GSS_S_COMPLETE) ret = ret2; if (mech_output_token != NULL) gss_release_buffer(&minor, mech_output_token); if (mech_buf.value != NULL) free(mech_buf.value); if (initialToken) free_NegTokenInit(&ni); else free_NegTokenResp(&na); } if (ret == GSS_S_COMPLETE) { if (src_name != NULL) { ret2 = gss_duplicate_name(minor_status, ctx->mech_src_name, src_name); if (ret2 != GSS_S_COMPLETE) ret = ret2; } if (delegated_cred_handle != NULL) { *delegated_cred_handle = ctx->delegated_cred_id; ctx->delegated_cred_id = GSS_C_NO_CREDENTIAL; } } if (mech_type != NULL) *mech_type = ctx->negotiated_mech_type; if (ret_flags != NULL) *ret_flags = ctx->mech_flags; if (time_rec != NULL) *time_rec = ctx->mech_time_rec; if (ret == GSS_S_COMPLETE || ret == GSS_S_CONTINUE_NEEDED) { HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex); return ret; } _gss_spnego_internal_delete_sec_context(&minor, context_handle, GSS_C_NO_BUFFER); return ret; }