/source4/kdc/proxy.c
C | 585 lines | 448 code | 83 blank | 54 comment | 52 complexity | d99b74475249e8f2967108f2e0f014f8 MD5 | raw file
- /*
- Unix SMB/CIFS implementation.
- KDC Server request proxying
- Copyright (C) Andrew Tridgell 2010
- Copyright (C) Andrew Bartlett 2010
- Copyright (C) Stefan Metzmacher 2011
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
- */
- #include "includes.h"
- #include "smbd/process_model.h"
- #include "lib/tsocket/tsocket.h"
- #include "libcli/util/tstream.h"
- #include "lib/util/tevent_ntstatus.h"
- #include "lib/stream/packet.h"
- #include "kdc/kdc-glue.h"
- #include "dsdb/samdb/samdb.h"
- #include "libcli/composite/composite.h"
- #include "libcli/resolve/resolve.h"
- /*
- get a list of our replication partners from repsFrom, returning it in *proxy_list
- */
- static WERROR kdc_proxy_get_writeable_dcs(struct kdc_server *kdc, TALLOC_CTX *mem_ctx, char ***proxy_list)
- {
- WERROR werr;
- uint32_t count, i;
- struct repsFromToBlob *reps;
- werr = dsdb_loadreps(kdc->samdb, mem_ctx, ldb_get_default_basedn(kdc->samdb), "repsFrom", &reps, &count);
- W_ERROR_NOT_OK_RETURN(werr);
- if (count == 0) {
- /* we don't have any DCs to replicate with. Very
- strange for a RODC */
- DEBUG(1,(__location__ ": No replication sources for RODC in KDC proxy\n"));
- talloc_free(reps);
- return WERR_DS_DRA_NO_REPLICA;
- }
- (*proxy_list) = talloc_array(mem_ctx, char *, count+1);
- W_ERROR_HAVE_NO_MEMORY_AND_FREE(*proxy_list, reps);
- talloc_steal(*proxy_list, reps);
- for (i=0; i<count; i++) {
- const char *dns_name = NULL;
- if (reps->version == 1) {
- dns_name = reps->ctr.ctr1.other_info->dns_name;
- } else if (reps->version == 2) {
- dns_name = reps->ctr.ctr2.other_info->dns_name1;
- }
- (*proxy_list)[i] = talloc_strdup(*proxy_list, dns_name);
- W_ERROR_HAVE_NO_MEMORY_AND_FREE((*proxy_list)[i], *proxy_list);
- }
- (*proxy_list)[i] = NULL;
- talloc_free(reps);
- return WERR_OK;
- }
- struct kdc_udp_proxy_state {
- struct tevent_context *ev;
- struct kdc_server *kdc;
- uint16_t port;
- DATA_BLOB in;
- DATA_BLOB out;
- char **proxy_list;
- uint32_t next_proxy;
- struct {
- struct nbt_name name;
- const char *ip;
- struct tdgram_context *dgram;
- } proxy;
- };
- static void kdc_udp_next_proxy(struct tevent_req *req);
- struct tevent_req *kdc_udp_proxy_send(TALLOC_CTX *mem_ctx,
- struct tevent_context *ev,
- struct kdc_server *kdc,
- uint16_t port,
- DATA_BLOB in)
- {
- struct tevent_req *req;
- struct kdc_udp_proxy_state *state;
- WERROR werr;
- req = tevent_req_create(mem_ctx, &state,
- struct kdc_udp_proxy_state);
- if (req == NULL) {
- return NULL;
- }
- state->ev = ev;
- state->kdc = kdc;
- state->port = port;
- state->in = in;
- werr = kdc_proxy_get_writeable_dcs(kdc, state, &state->proxy_list);
- if (!W_ERROR_IS_OK(werr)) {
- NTSTATUS status = werror_to_ntstatus(werr);
- tevent_req_nterror(req, status);
- return tevent_req_post(req, ev);
- }
- kdc_udp_next_proxy(req);
- if (!tevent_req_is_in_progress(req)) {
- return tevent_req_post(req, ev);
- }
- return req;
- }
- static void kdc_udp_proxy_resolve_done(struct composite_context *csubreq);
- /*
- try the next proxy in the list
- */
- static void kdc_udp_next_proxy(struct tevent_req *req)
- {
- struct kdc_udp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_udp_proxy_state);
- const char *proxy_dnsname = state->proxy_list[state->next_proxy];
- struct composite_context *csubreq;
- if (proxy_dnsname == NULL) {
- tevent_req_nterror(req, NT_STATUS_NO_LOGON_SERVERS);
- return;
- }
- state->next_proxy++;
- /* make sure we close the socket of the last try */
- TALLOC_FREE(state->proxy.dgram);
- ZERO_STRUCT(state->proxy);
- make_nbt_name(&state->proxy.name, proxy_dnsname, 0);
- csubreq = resolve_name_ex_send(lpcfg_resolve_context(state->kdc->task->lp_ctx),
- state,
- RESOLVE_NAME_FLAG_FORCE_DNS,
- 0,
- &state->proxy.name,
- state->ev);
- if (tevent_req_nomem(csubreq, req)) {
- return;
- }
- csubreq->async.fn = kdc_udp_proxy_resolve_done;
- csubreq->async.private_data = req;
- }
- static void kdc_udp_proxy_sendto_done(struct tevent_req *subreq);
- static void kdc_udp_proxy_recvfrom_done(struct tevent_req *subreq);
- static void kdc_udp_proxy_resolve_done(struct composite_context *csubreq)
- {
- struct tevent_req *req =
- talloc_get_type_abort(csubreq->async.private_data,
- struct tevent_req);
- struct kdc_udp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_udp_proxy_state);
- NTSTATUS status;
- struct tevent_req *subreq;
- struct tsocket_address *local_addr, *proxy_addr;
- int ret;
- status = resolve_name_recv(csubreq, state, &state->proxy.ip);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(0,("Unable to resolve proxy[%s] - %s\n",
- state->proxy.name.name, nt_errstr(status)));
- kdc_udp_next_proxy(req);
- return;
- }
- /* get an address for us to use locally */
- ret = tsocket_address_inet_from_strings(state, "ip", NULL, 0, &local_addr);
- if (ret != 0) {
- kdc_udp_next_proxy(req);
- return;
- }
- ret = tsocket_address_inet_from_strings(state, "ip",
- state->proxy.ip,
- state->port,
- &proxy_addr);
- if (ret != 0) {
- kdc_udp_next_proxy(req);
- return;
- }
- /* create a socket for us to work on */
- ret = tdgram_inet_udp_socket(local_addr, proxy_addr,
- state, &state->proxy.dgram);
- if (ret != 0) {
- kdc_udp_next_proxy(req);
- return;
- }
- subreq = tdgram_sendto_send(state,
- state->ev,
- state->proxy.dgram,
- state->in.data,
- state->in.length,
- NULL);
- if (tevent_req_nomem(subreq, req)) {
- return;
- }
- tevent_req_set_callback(subreq, kdc_udp_proxy_sendto_done, req);
- /* setup to receive the reply from the proxy */
- subreq = tdgram_recvfrom_send(state, state->ev, state->proxy.dgram);
- if (tevent_req_nomem(subreq, req)) {
- return;
- }
- tevent_req_set_callback(subreq, kdc_udp_proxy_recvfrom_done, req);
- tevent_req_set_endtime(subreq, state->ev,
- timeval_current_ofs(state->kdc->proxy_timeout, 0));
- DEBUG(4,("kdc_udp_proxy: proxying request to %s[%s]\n",
- state->proxy.name.name, state->proxy.ip));
- }
- /*
- called when the send of the call to the proxy is complete
- this is used to get an errors from the sendto()
- */
- static void kdc_udp_proxy_sendto_done(struct tevent_req *subreq)
- {
- struct tevent_req *req =
- tevent_req_callback_data(subreq,
- struct tevent_req);
- struct kdc_udp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_udp_proxy_state);
- ssize_t ret;
- int sys_errno;
- ret = tdgram_sendto_recv(subreq, &sys_errno);
- TALLOC_FREE(subreq);
- if (ret == -1) {
- DEBUG(4,("kdc_udp_proxy: sendto for %s[%s] gave %d : %s\n",
- state->proxy.name.name, state->proxy.ip,
- sys_errno, strerror(sys_errno)));
- kdc_udp_next_proxy(req);
- }
- }
- /*
- called when the proxy replies
- */
- static void kdc_udp_proxy_recvfrom_done(struct tevent_req *subreq)
- {
- struct tevent_req *req =
- tevent_req_callback_data(subreq,
- struct tevent_req);
- struct kdc_udp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_udp_proxy_state);
- int sys_errno;
- uint8_t *buf;
- ssize_t len;
- len = tdgram_recvfrom_recv(subreq, &sys_errno,
- state, &buf, NULL);
- TALLOC_FREE(subreq);
- if (len == -1) {
- DEBUG(4,("kdc_udp_proxy: reply from %s[%s] gave %d : %s\n",
- state->proxy.name.name, state->proxy.ip,
- sys_errno, strerror(sys_errno)));
- kdc_udp_next_proxy(req);
- return;
- }
- /*
- * Check the reply came from the right IP?
- * As we use connected udp sockets, that should not be needed...
- */
- state->out.length = len;
- state->out.data = buf;
- tevent_req_done(req);
- }
- NTSTATUS kdc_udp_proxy_recv(struct tevent_req *req,
- TALLOC_CTX *mem_ctx,
- DATA_BLOB *out)
- {
- struct kdc_udp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_udp_proxy_state);
- NTSTATUS status;
- if (tevent_req_is_nterror(req, &status)) {
- tevent_req_received(req);
- return status;
- }
- out->data = talloc_move(mem_ctx, &state->out.data);
- out->length = state->out.length;
- tevent_req_received(req);
- return NT_STATUS_OK;
- }
- struct kdc_tcp_proxy_state {
- struct tevent_context *ev;
- struct kdc_server *kdc;
- uint16_t port;
- DATA_BLOB in;
- uint8_t in_hdr[4];
- struct iovec in_iov[2];
- DATA_BLOB out;
- char **proxy_list;
- uint32_t next_proxy;
- struct {
- struct nbt_name name;
- const char *ip;
- struct tstream_context *stream;
- } proxy;
- };
- static void kdc_tcp_next_proxy(struct tevent_req *req);
- struct tevent_req *kdc_tcp_proxy_send(TALLOC_CTX *mem_ctx,
- struct tevent_context *ev,
- struct kdc_server *kdc,
- uint16_t port,
- DATA_BLOB in)
- {
- struct tevent_req *req;
- struct kdc_tcp_proxy_state *state;
- WERROR werr;
- req = tevent_req_create(mem_ctx, &state,
- struct kdc_tcp_proxy_state);
- if (req == NULL) {
- return NULL;
- }
- state->ev = ev;
- state->kdc = kdc;
- state->port = port;
- state->in = in;
- werr = kdc_proxy_get_writeable_dcs(kdc, state, &state->proxy_list);
- if (!W_ERROR_IS_OK(werr)) {
- NTSTATUS status = werror_to_ntstatus(werr);
- tevent_req_nterror(req, status);
- return tevent_req_post(req, ev);
- }
- RSIVAL(state->in_hdr, 0, state->in.length);
- state->in_iov[0].iov_base = (char *)state->in_hdr;
- state->in_iov[0].iov_len = 4;
- state->in_iov[1].iov_base = (char *)state->in.data;
- state->in_iov[1].iov_len = state->in.length;
- kdc_tcp_next_proxy(req);
- if (!tevent_req_is_in_progress(req)) {
- return tevent_req_post(req, ev);
- }
- return req;
- }
- static void kdc_tcp_proxy_resolve_done(struct composite_context *csubreq);
- /*
- try the next proxy in the list
- */
- static void kdc_tcp_next_proxy(struct tevent_req *req)
- {
- struct kdc_tcp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_tcp_proxy_state);
- const char *proxy_dnsname = state->proxy_list[state->next_proxy];
- struct composite_context *csubreq;
- if (proxy_dnsname == NULL) {
- tevent_req_nterror(req, NT_STATUS_NO_LOGON_SERVERS);
- return;
- }
- state->next_proxy++;
- /* make sure we close the socket of the last try */
- TALLOC_FREE(state->proxy.stream);
- ZERO_STRUCT(state->proxy);
- make_nbt_name(&state->proxy.name, proxy_dnsname, 0);
- csubreq = resolve_name_ex_send(lpcfg_resolve_context(state->kdc->task->lp_ctx),
- state,
- RESOLVE_NAME_FLAG_FORCE_DNS,
- 0,
- &state->proxy.name,
- state->ev);
- if (tevent_req_nomem(csubreq, req)) {
- return;
- }
- csubreq->async.fn = kdc_tcp_proxy_resolve_done;
- csubreq->async.private_data = req;
- }
- static void kdc_tcp_proxy_connect_done(struct tevent_req *subreq);
- static void kdc_tcp_proxy_resolve_done(struct composite_context *csubreq)
- {
- struct tevent_req *req =
- talloc_get_type_abort(csubreq->async.private_data,
- struct tevent_req);
- struct kdc_tcp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_tcp_proxy_state);
- NTSTATUS status;
- struct tevent_req *subreq;
- struct tsocket_address *local_addr, *proxy_addr;
- int ret;
- status = resolve_name_recv(csubreq, state, &state->proxy.ip);
- if (!NT_STATUS_IS_OK(status)) {
- DEBUG(0,("Unable to resolve proxy[%s] - %s\n",
- state->proxy.name.name, nt_errstr(status)));
- kdc_tcp_next_proxy(req);
- return;
- }
- /* get an address for us to use locally */
- ret = tsocket_address_inet_from_strings(state, "ip", NULL, 0, &local_addr);
- if (ret != 0) {
- kdc_tcp_next_proxy(req);
- return;
- }
- ret = tsocket_address_inet_from_strings(state, "ip",
- state->proxy.ip,
- state->port,
- &proxy_addr);
- if (ret != 0) {
- kdc_tcp_next_proxy(req);
- return;
- }
- subreq = tstream_inet_tcp_connect_send(state, state->ev,
- local_addr, proxy_addr);
- if (tevent_req_nomem(subreq, req)) {
- return;
- }
- tevent_req_set_callback(subreq, kdc_tcp_proxy_connect_done, req);
- tevent_req_set_endtime(subreq, state->ev,
- timeval_current_ofs(state->kdc->proxy_timeout, 0));
- }
- static void kdc_tcp_proxy_writev_done(struct tevent_req *subreq);
- static void kdc_tcp_proxy_read_pdu_done(struct tevent_req *subreq);
- static void kdc_tcp_proxy_connect_done(struct tevent_req *subreq)
- {
- struct tevent_req *req =
- tevent_req_callback_data(subreq,
- struct tevent_req);
- struct kdc_tcp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_tcp_proxy_state);
- int ret, sys_errno;
- ret = tstream_inet_tcp_connect_recv(subreq, &sys_errno,
- state, &state->proxy.stream, NULL);
- TALLOC_FREE(subreq);
- if (ret != 0) {
- kdc_tcp_next_proxy(req);
- return;
- }
- subreq = tstream_writev_send(state,
- state->ev,
- state->proxy.stream,
- state->in_iov, 2);
- if (tevent_req_nomem(subreq, req)) {
- return;
- }
- tevent_req_set_callback(subreq, kdc_tcp_proxy_writev_done, req);
- subreq = tstream_read_pdu_blob_send(state,
- state->ev,
- state->proxy.stream,
- 4, /* initial_read_size */
- packet_full_request_u32,
- req);
- if (tevent_req_nomem(subreq, req)) {
- return;
- }
- tevent_req_set_callback(subreq, kdc_tcp_proxy_read_pdu_done, req);
- tevent_req_set_endtime(subreq, state->kdc->task->event_ctx,
- timeval_current_ofs(state->kdc->proxy_timeout, 0));
- DEBUG(4,("kdc_tcp_proxy: proxying request to %s[%s]\n",
- state->proxy.name.name, state->proxy.ip));
- }
- static void kdc_tcp_proxy_writev_done(struct tevent_req *subreq)
- {
- struct tevent_req *req =
- tevent_req_callback_data(subreq,
- struct tevent_req);
- int ret, sys_errno;
- ret = tstream_writev_recv(subreq, &sys_errno);
- TALLOC_FREE(subreq);
- if (ret == -1) {
- kdc_tcp_next_proxy(req);
- }
- }
- static void kdc_tcp_proxy_read_pdu_done(struct tevent_req *subreq)
- {
- struct tevent_req *req =
- tevent_req_callback_data(subreq,
- struct tevent_req);
- struct kdc_tcp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_tcp_proxy_state);
- NTSTATUS status;
- DATA_BLOB raw;
- status = tstream_read_pdu_blob_recv(subreq, state, &raw);
- TALLOC_FREE(subreq);
- if (!NT_STATUS_IS_OK(status)) {
- kdc_tcp_next_proxy(req);
- return;
- }
- /*
- * raw blob has the length in the first 4 bytes,
- * which we do not need here.
- */
- state->out = data_blob_talloc(state, raw.data + 4, raw.length - 4);
- if (state->out.length != raw.length - 4) {
- tevent_req_oom(req);
- return;
- }
- tevent_req_done(req);
- }
- NTSTATUS kdc_tcp_proxy_recv(struct tevent_req *req,
- TALLOC_CTX *mem_ctx,
- DATA_BLOB *out)
- {
- struct kdc_tcp_proxy_state *state =
- tevent_req_data(req,
- struct kdc_tcp_proxy_state);
- NTSTATUS status;
- if (tevent_req_is_nterror(req, &status)) {
- tevent_req_received(req);
- return status;
- }
- out->data = talloc_move(mem_ctx, &state->out.data);
- out->length = state->out.length;
- tevent_req_received(req);
- return NT_STATUS_OK;
- }