source: vendor/3.6.23/source3/libsmb/clidgram.c

/* 
   Unix SMB/CIFS implementation.
   client dgram calls
   Copyright (C) Andrew Tridgell 1994-1998
   Copyright (C) Richard Sharpe 2001
   Copyright (C) John Terpstra 2001

   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 "libsmb/libsmb.h"
#include "../lib/util/tevent_ntstatus.h"
#include "libsmb/clidgram.h"
#include "libsmb/nmblib.h"
#include "messages.h"

/*
 * cli_send_mailslot, send a mailslot for client code ...
 */

static bool cli_prep_mailslot(bool unique, const char *mailslot,
                       uint16 priority,
                       char *buf, int len,
                       const char *srcname, int src_type,
                       const char *dstname, int dest_type,
                       const struct sockaddr_storage *dest_ss,
                       int dgm_id,
                       struct packet_struct *p)
{
        struct dgram_packet *dgram = &p->packet.dgram;
        char *ptr, *p2;
        char tmp[4];
        char addr[INET6_ADDRSTRLEN];

        ZERO_STRUCTP(p);

        /*
         * Next, build the DGRAM ...
         */

        /* DIRECT GROUP or UNIQUE datagram. */
        dgram->header.msg_type = unique ? 0x10 : 0x11;
        dgram->header.flags.node_type = M_NODE;
        dgram->header.flags.first = True;
        dgram->header.flags.more = False;
        dgram->header.dgm_id = dgm_id;
        /* source ip is filled by nmbd */
        dgram->header.dgm_length = 0; /* Let build_dgram() handle this. */
        dgram->header.packet_offset = 0;

        make_nmb_name(&dgram->source_name,srcname,src_type);
        make_nmb_name(&dgram->dest_name,dstname,dest_type);

        ptr = &dgram->data[0];

        /* Setup the smb part. */
        ptr -= 4; /* XXX Ugliness because of handling of tcp SMB length. */
        memcpy(tmp,ptr,4);

        if (smb_size + 17*2 + strlen(mailslot) + 1 + len > MAX_DGRAM_SIZE) {
                DEBUG(0, ("cli_send_mailslot: Cannot write beyond end of packet\n"));
                return False;
        }

        cli_set_message(ptr,17,strlen(mailslot) + 1 + len,True);
        memcpy(ptr,tmp,4);

        SCVAL(ptr,smb_com,SMBtrans);
        SSVAL(ptr,smb_vwv1,len);
        SSVAL(ptr,smb_vwv11,len);
        SSVAL(ptr,smb_vwv12,70 + strlen(mailslot));
        SSVAL(ptr,smb_vwv13,3);
        SSVAL(ptr,smb_vwv14,1);
        SSVAL(ptr,smb_vwv15,priority);
        SSVAL(ptr,smb_vwv16,2);
        p2 = smb_buf(ptr);
        fstrcpy(p2,mailslot);
        p2 = skip_string(ptr,MAX_DGRAM_SIZE,p2);
        if (!p2) {
                return False;
        }

        memcpy(p2,buf,len);
        p2 += len;

        dgram->datasize = PTR_DIFF(p2,ptr+4); /* +4 for tcp length. */

        p->packet_type = DGRAM_PACKET;
        p->ip = ((const struct sockaddr_in *)dest_ss)->sin_addr;
        p->timestamp = time(NULL);

        DEBUG(4,("send_mailslot: Sending to mailslot %s from %s ",
                 mailslot, nmb_namestr(&dgram->source_name)));
        print_sockaddr(addr, sizeof(addr), dest_ss);

        DEBUGADD(4,("to %s IP %s\n", nmb_namestr(&dgram->dest_name), addr));

        return true;
}

static char *mailslot_name(TALLOC_CTX *mem_ctx, struct in_addr dc_ip)
{
        return talloc_asprintf(mem_ctx, "%s%X",
                               NBT_MAILSLOT_GETDC, dc_ip.s_addr);
}

static bool prep_getdc_request(const struct sockaddr_storage *dc_ss,
                               const char *domain_name,
                               const struct dom_sid *sid,
                               uint32_t nt_version,
                               const char *my_mailslot,
                               int dgm_id,
                               struct packet_struct *p)
{
        TALLOC_CTX *frame = talloc_stackframe();
        const char *my_acct_name;
        struct nbt_netlogon_packet packet;
        struct NETLOGON_SAM_LOGON_REQUEST *s;
        enum ndr_err_code ndr_err;
        DATA_BLOB blob = data_blob_null;
        struct dom_sid my_sid;
        bool ret = false;

        ZERO_STRUCT(packet);
        ZERO_STRUCT(my_sid);

        if (sid != NULL) {
                my_sid = *sid;
        }

        my_acct_name = talloc_asprintf(talloc_tos(), "%s$", global_myname());
        if (my_acct_name == NULL) {
                goto fail;
        }

        packet.command  = LOGON_SAM_LOGON_REQUEST;
        s               = &packet.req.logon;

        s->request_count        = 0;
        s->computer_name        = global_myname();
        s->user_name            = my_acct_name;
        s->mailslot_name        = my_mailslot;
        s->acct_control         = ACB_WSTRUST;
        s->sid                  = my_sid;
        s->nt_version           = nt_version;
        s->lmnt_token           = 0xffff;
        s->lm20_token           = 0xffff;

        if (DEBUGLEVEL >= 10) {
                NDR_PRINT_DEBUG(nbt_netlogon_packet, &packet);
        }

        ndr_err = ndr_push_struct_blob(&blob, talloc_tos(), &packet,
                       (ndr_push_flags_fn_t)ndr_push_nbt_netlogon_packet);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
                goto fail;
        }

        ret = cli_prep_mailslot(false, NBT_MAILSLOT_NTLOGON, 0,
                                (char *)blob.data, blob.length,
                                global_myname(), 0, domain_name, 0x1c,
                                dc_ss, dgm_id, p);
fail:
        TALLOC_FREE(frame);
        return ret;
}

static bool parse_getdc_response(
        struct packet_struct *packet,
        TALLOC_CTX *mem_ctx,
        const char *domain_name,
        uint32_t *nt_version,
        const char **dc_name,
        struct netlogon_samlogon_response **samlogon_response)
{
        DATA_BLOB blob;
        struct netlogon_samlogon_response *r;
        union dgram_message_body p;
        enum ndr_err_code ndr_err;
        NTSTATUS status;

        const char *returned_dc = NULL;
        const char *returned_domain = NULL;

        blob = data_blob_const(packet->packet.dgram.data,
                               packet->packet.dgram.datasize);
        if (blob.length < 4) {
                DEBUG(1, ("invalid length: %d\n", (int)blob.length));
                return false;
        }

        if (RIVAL(blob.data,0) != DGRAM_SMB) {
                DEBUG(1, ("invalid packet\n"));
                return false;
        }

        blob.data += 4;
        blob.length -= 4;

        ndr_err = ndr_pull_union_blob_all(&blob, mem_ctx, &p, DGRAM_SMB,
                       (ndr_pull_flags_fn_t)ndr_pull_dgram_smb_packet);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
                DEBUG(1, ("failed to parse packet\n"));
                return false;
        }

        if (p.smb.smb_command != SMB_TRANSACTION) {
                DEBUG(1, ("invalid smb_command: %d\n", p.smb.smb_command));
                return false;
        }

        if (DEBUGLEVEL >= 10) {
                NDR_PRINT_DEBUG(dgram_smb_packet, &p);
        }

        blob = p.smb.body.trans.data;

        r = TALLOC_ZERO_P(mem_ctx, struct netlogon_samlogon_response);
        if (!r) {
                return false;
        }

        status = pull_netlogon_samlogon_response(&blob, r, r);
        if (!NT_STATUS_IS_OK(status)) {
                TALLOC_FREE(r);
                return false;
        }

        map_netlogon_samlogon_response(r);

        /* do we still need this ? */
        *nt_version = r->ntver;

        returned_domain = r->data.nt5_ex.domain_name;
        returned_dc = r->data.nt5_ex.pdc_name;

        if (!strequal(returned_domain, domain_name)) {
                DEBUG(3, ("GetDC: Expected domain %s, got %s\n",
                          domain_name, returned_domain));
                TALLOC_FREE(r);
                return false;
        }

        if (*returned_dc == '\\') returned_dc += 1;
        if (*returned_dc == '\\') returned_dc += 1;

        *dc_name = talloc_strdup(mem_ctx, returned_dc);
        if (!*dc_name) {
                TALLOC_FREE(r);
                return false;
        }

        if (samlogon_response) {
                *samlogon_response = r;
        } else {
                TALLOC_FREE(r);
        }

        DEBUG(10, ("GetDC gave name %s for domain %s\n",
                   *dc_name, returned_domain));

        return True;
}

struct nbt_getdc_state {
        struct tevent_context *ev;
        struct messaging_context *msg_ctx;
        struct nb_packet_reader *reader;
        const char *my_mailslot;
        pid_t nmbd_pid;

        const struct sockaddr_storage *dc_addr;
        const char *domain_name;
        const struct dom_sid *sid;
        uint32_t nt_version;
        const char *dc_name;
        struct netlogon_samlogon_response *samlogon_response;

        struct packet_struct p;
};

static void nbt_getdc_got_reader(struct tevent_req *subreq);
static void nbt_getdc_got_response(struct tevent_req *subreq);

struct tevent_req *nbt_getdc_send(TALLOC_CTX *mem_ctx,
                                  struct tevent_context *ev,
                                  struct messaging_context *msg_ctx,
                                  const struct sockaddr_storage *dc_addr,
                                  const char *domain_name,
                                  const struct dom_sid *sid,
                                  uint32_t nt_version)
{
        struct tevent_req *req, *subreq;
        struct nbt_getdc_state *state;
        uint16_t dgm_id;

        req = tevent_req_create(mem_ctx, &state, struct nbt_getdc_state);
        if (req == NULL) {
                return NULL;
        }
        state->ev = ev;
        state->msg_ctx = msg_ctx;
        state->dc_addr = dc_addr;
        state->domain_name = domain_name;
        state->sid = sid;
        state->nt_version = nt_version;

        if (dc_addr->ss_family != AF_INET) {
                tevent_req_nterror(req, NT_STATUS_NOT_SUPPORTED);
                return tevent_req_post(req, ev);
        }
        state->my_mailslot = mailslot_name(
                state, ((struct sockaddr_in *)dc_addr)->sin_addr);
        if (tevent_req_nomem(state->my_mailslot, req)) {
                return tevent_req_post(req, ev);
        }
        state->nmbd_pid = pidfile_pid("nmbd");
        if (state->nmbd_pid == 0) {
                DEBUG(3, ("No nmbd found\n"));
                tevent_req_nterror(req, NT_STATUS_NOT_SUPPORTED);
                return tevent_req_post(req, ev);
        }

        generate_random_buffer((uint8_t *)(void *)&dgm_id, sizeof(dgm_id));

        if (!prep_getdc_request(dc_addr, domain_name, sid, nt_version,
                                state->my_mailslot, dgm_id & 0x7fff,
                                &state->p)) {
                DEBUG(3, ("prep_getdc_request failed\n"));
                tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
                return tevent_req_post(req, ev);
        }

        subreq = nb_packet_reader_send(state, ev, DGRAM_PACKET, -1,
                                       state->my_mailslot);
        if (tevent_req_nomem(subreq, req)) {
                return tevent_req_post(req, ev);
        }
        tevent_req_set_callback(subreq, nbt_getdc_got_reader, req);
        return req;
}

static void nbt_getdc_got_reader(struct tevent_req *subreq)
{
        struct tevent_req *req = tevent_req_callback_data(
                subreq, struct tevent_req);
        struct nbt_getdc_state *state = tevent_req_data(
                req, struct nbt_getdc_state);
        NTSTATUS status;

        status = nb_packet_reader_recv(subreq, state, &state->reader);
        TALLOC_FREE(subreq);
        if (tevent_req_nterror(req, status)) {
                DEBUG(10, ("nb_packet_reader_recv returned %s\n",
                           nt_errstr(status)));
                return;
        }

        status = messaging_send_buf(
                state->msg_ctx, pid_to_procid(state->nmbd_pid),
                MSG_SEND_PACKET, (uint8_t *)&state->p, sizeof(state->p));

        if (tevent_req_nterror(req, status)) {
                DEBUG(10, ("messaging_send_buf returned %s\n",
                           nt_errstr(status)));
                return;
        }
        subreq = nb_packet_read_send(state, state->ev, state->reader);
        if (tevent_req_nomem(subreq, req)) {
                return;
        }
        tevent_req_set_callback(subreq, nbt_getdc_got_response, req);
}

static void nbt_getdc_got_response(struct tevent_req *subreq)
{
        struct tevent_req *req = tevent_req_callback_data(
                subreq, struct tevent_req);
        struct nbt_getdc_state *state = tevent_req_data(
                req, struct nbt_getdc_state);
        struct packet_struct *p;
        NTSTATUS status;
        bool ret;

        status = nb_packet_read_recv(subreq, &p);
        TALLOC_FREE(subreq);
        if (tevent_req_nterror(req, status)) {
                return;
        }

        ret = parse_getdc_response(p, state, state->domain_name,
                                   &state->nt_version, &state->dc_name,
                                   &state->samlogon_response);
        free_packet(p);
        if (!ret) {
                tevent_req_nterror(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
                return;
        }
        tevent_req_done(req);
}

NTSTATUS nbt_getdc_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
                        uint32_t *nt_version, const char **dc_name,
                        struct netlogon_samlogon_response **samlogon_response)
{
        struct nbt_getdc_state *state = tevent_req_data(
                req, struct nbt_getdc_state);
        NTSTATUS status;

        if (tevent_req_is_nterror(req, &status)) {
                return status;
        }
        if (nt_version != NULL) {
                *nt_version = state->nt_version;
        }
        if (dc_name != NULL) {
                *dc_name = talloc_move(mem_ctx, &state->dc_name);
        }
        if (samlogon_response != NULL) {
                *samlogon_response = talloc_move(
                        mem_ctx, &state->samlogon_response);
        }
        return NT_STATUS_OK;
}

NTSTATUS nbt_getdc(struct messaging_context *msg_ctx,
                   uint32_t timeout_in_seconds,
                   const struct sockaddr_storage *dc_addr,
                   const char *domain_name,
                   const struct dom_sid *sid,
                   uint32_t nt_version,
                   TALLOC_CTX *mem_ctx,
                   uint32_t *pnt_version,
                   const char **dc_name,
                   struct netlogon_samlogon_response **samlogon_response)
{
        TALLOC_CTX *frame = talloc_stackframe();
        struct tevent_context *ev;
        struct tevent_req *req;
        NTSTATUS status = NT_STATUS_NO_MEMORY;

        ev = tevent_context_init(frame);
        if (ev == NULL) {
                goto fail;
        }
        req = nbt_getdc_send(ev, ev, msg_ctx, dc_addr, domain_name,
                             sid, nt_version);
        if (req == NULL) {
                goto fail;
        }
        if (!tevent_req_set_endtime(req, ev,
                        timeval_current_ofs(timeout_in_seconds, 0))) {
                goto fail;
        }
        if (!tevent_req_poll_ntstatus(req, ev, &status)) {
                goto fail;
        }
        status = nbt_getdc_recv(req, mem_ctx, pnt_version, dc_name,
                                samlogon_response);
 fail:
        TALLOC_FREE(frame);
        return status;
}