source4/lib/http/http_auth.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    HTTP library
   5
   6    Copyright (C) 2014 Samuel Cabrero <samuelcabrero@kernevil.me>
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "includes.h"
  23 #include "http.h"
  24 #include "http_internal.h"
  25 #include "lib/util/tevent_ntstatus.h"
  26 #include "lib/param/param.h"
  27 #include "tevent.h"
  28 #include "auth/gensec/gensec.h"
  29 #include "auth/credentials/credentials.h"
  30 #include "lib/util/data_blob.h"
  31
  32 /**
  33  * Copy the request headers from src to dst
  34  */
  35 static NTSTATUS http_copy_header(const struct http_request *src,
  36                                  struct http_request *dst)
  37 {
  38         struct http_header *h;
  39
  40         dst->type = src->type;
  41         dst->major = src->major;
  42         dst->minor = src->minor;
  43         dst->uri = talloc_strdup(dst, src->uri);
  44
  45         for (h = src->headers; h != NULL; h = h->next) {
  46                 http_add_header(dst, &dst->headers, h->key, h->value);
  47         }
  48         dst->headers_size = src->headers_size;
  49
  50         return NT_STATUS_OK;
  51 }
  52
  53 /*
  54  * Retrieve the WWW-Authenticate header from server response based on the
  55  * authentication scheme being used.
  56  */
  57 static NTSTATUS http_parse_auth_response(enum http_auth_method auth,
  58                                          struct http_request *auth_response,
  59                                          DATA_BLOB *in)
  60 {
  61         struct http_header *h;
  62
  63         for (h = auth_response->headers; h != NULL; h = h->next) {
  64                 if (strncasecmp(h->key, "WWW-Authenticate", 16) == 0) {
  65                         switch (auth) {
  66                         case HTTP_AUTH_NTLM:
  67                                 if (strncasecmp(h->value, "NTLM ", 5) == 0) {
  68                                         *in = data_blob_string_const(h->value);
  69                                         return NT_STATUS_OK;
  70                                 }
  71                                 break;
  72                         default:
  73                                 break;
  74                         }
  75                 }
  76         }
  77
  78         return NT_STATUS_NOT_SUPPORTED;
  79 }
  80
  81 struct http_auth_state {
  82         struct tevent_context *ev;
  83
  84         struct tstream_context *stream;
  85         struct tevent_queue *send_queue;
  86
  87         enum http_auth_method auth;
  88
  89         struct gensec_security *gensec_ctx;
  90         NTSTATUS gensec_status;
  91
  92         const struct http_request *original_request;
  93         struct http_request *next_request;
  94         struct http_request *auth_response;
  95 };
  96
  97
  98 static void http_send_auth_request_gensec_done(struct tevent_req *subreq);
  99 static void http_send_auth_request_http_req_done(struct tevent_req *subreq);
 100 static void http_send_auth_request_http_rep_done(struct tevent_req *subreq);
 101
 102 struct tevent_req *http_send_auth_request_send(TALLOC_CTX *mem_ctx,
 103                                                struct tevent_context *ev,
 104                                                struct tstream_context *stream,
 105                                                struct tevent_queue *send_queue,
 106                                                const struct http_request *original_request,
 107                                                struct cli_credentials *credentials,
 108                                                struct loadparm_context *lp_ctx,
 109                                                enum http_auth_method auth)
 110 {
 111         struct tevent_req *req = NULL;
 112         struct http_auth_state *state = NULL;
 113         struct tevent_req *subreq = NULL;
 114         DATA_BLOB gensec_in = data_blob_null;
 115         NTSTATUS status;
 116         const char *mech_name = NULL;
 117
 118         req = tevent_req_create(mem_ctx, &state, struct http_auth_state);
 119         if (req == NULL) {
 120                 return NULL;
 121         }
 122         state->ev = ev;
 123         state->stream = stream;
 124         state->send_queue = send_queue;
 125         state->auth = auth;
 126         state->original_request = original_request;
 127
 128         status = gensec_init();
 129         if (tevent_req_nterror(req, status)) {
 130                 return tevent_req_post(req, ev);
 131         }
 132
 133         status = gensec_client_start(state, &state->gensec_ctx,
 134                                      lpcfg_gensec_settings(state, lp_ctx));
 135         if (tevent_req_nterror(req, status)) {
 136                 return tevent_req_post(req, ev);
 137         }
 138
 139         status = gensec_set_credentials(state->gensec_ctx, credentials);
 140         if (tevent_req_nterror(req, status)) {
 141                 return tevent_req_post(req, ev);
 142         }
 143
 144         switch (state->auth) {
 145         case HTTP_AUTH_BASIC:
 146                 mech_name = "http_basic";
 147                 break;
 148         case HTTP_AUTH_NTLM:
 149                 mech_name = "http_ntlm";
 150                 break;
 151         default:
 152                 tevent_req_nterror(req, NT_STATUS_NOT_SUPPORTED);
 153                 return tevent_req_post(req, ev);
 154         }
 155
 156         status = gensec_start_mech_by_name(state->gensec_ctx, mech_name);
 157         if (tevent_req_nterror(req, status)) {
 158                 return tevent_req_post(req, ev);
 159         }
 160
 161         subreq = gensec_update_send(state, state->ev,
 162                                     state->gensec_ctx,
 163                                     gensec_in);
 164         if (tevent_req_nomem(subreq, req)) {
 165                 return tevent_req_post(req, ev);
 166         }
 167         tevent_req_set_callback(subreq, http_send_auth_request_gensec_done, req);
 168
 169         return req;
 170 }
 171
 172 static void http_send_auth_request_gensec_done(struct tevent_req *subreq)
 173 {
 174         struct tevent_req *req =
 175                 tevent_req_callback_data(subreq,
 176                 struct tevent_req);
 177         struct http_auth_state *state =
 178                 tevent_req_data(req,
 179                 struct http_auth_state);
 180         DATA_BLOB gensec_out = data_blob_null;
 181         NTSTATUS status;
 182         int ret;
 183
 184         TALLOC_FREE(state->auth_response);
 185
 186         status = gensec_update_recv(subreq, state, &gensec_out);
 187         TALLOC_FREE(subreq);
 188         state->gensec_status = status;
 189         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 190                 status = NT_STATUS_OK;
 191         }
 192         if (tevent_req_nterror(req, status)) {
 193                 return;
 194         }
 195
 196         state->next_request = talloc_zero(state, struct http_request);
 197         if (tevent_req_nomem(state->next_request, req)) {
 198                 return;
 199         }
 200
 201         status = http_copy_header(state->original_request, state->next_request);
 202         if (tevent_req_nterror(req, status)) {
 203                 return;
 204         }
 205
 206         if (!NT_STATUS_IS_OK(state->gensec_status)) {
 207                 /*
 208                  * More preprocessing required before we
 209                  * can include the content.
 210                  */
 211                 ret = http_replace_header(state->next_request,
 212                                           &state->next_request->headers,
 213                                           "Content-Length", "0");
 214                 if (ret != 0) {
 215                         tevent_req_oom(req);
 216                         return;
 217                 }
 218         } else {
 219                 state->next_request->body = state->original_request->body;
 220         }
 221
 222         if (gensec_out.length > 0) {
 223                 ret = http_add_header(state->next_request,
 224                                       &state->next_request->headers,
 225                                       "Authorization",
 226                                       (char *)gensec_out.data);
 227                 if (ret != 0) {
 228                         tevent_req_oom(req);
 229                         return;
 230                 }
 231                 data_blob_free(&gensec_out);
 232         }
 233
 234         subreq = http_send_request_send(state, state->ev,
 235                                         state->stream,
 236                                         state->send_queue,
 237                                         state->next_request);
 238         if (tevent_req_nomem(subreq, req)) {
 239                 return;
 240         }
 241         tevent_req_set_callback(subreq,
 242                                 http_send_auth_request_http_req_done,
 243                                 req);
 244 }
 245
 246 static void http_send_auth_request_http_req_done(struct tevent_req *subreq)
 247 {
 248         struct tevent_req *req =
 249                 tevent_req_callback_data(subreq,
 250                 struct tevent_req);
 251         struct http_auth_state *state =
 252                 tevent_req_data(req,
 253                 struct http_auth_state);
 254         NTSTATUS status;
 255
 256         TALLOC_FREE(state->next_request);
 257
 258         status = http_send_request_recv(subreq);
 259         TALLOC_FREE(subreq);
 260         if (tevent_req_nterror(req, status)) {
 261                 return;
 262         }
 263
 264         /*
 265          * If no more processing required, it is done
 266          *
 267          * The caller will use http_read_response_send/recv
 268          * in order to get the high level response.
 269          */
 270         if (NT_STATUS_IS_OK(state->gensec_status)) {
 271                 tevent_req_done(req);
 272                 return;
 273         }
 274
 275         /*
 276          * If more processing required, read the response from server
 277          *
 278          * We may get an empty RPCH Echo packet from the server
 279          * on the "RPC_OUT_DATA" path. We need to consume this
 280          * from the socket, but for now we just ignore the bytes.
 281          */
 282         subreq = http_read_response_send(state, state->ev,
 283                                          state->stream,
 284                                          UINT16_MAX);
 285         if (tevent_req_nomem(subreq, req)) {
 286                 return;
 287         }
 288         tevent_req_set_callback(subreq,
 289                                 http_send_auth_request_http_rep_done,
 290                                 req);
 291 }
 292
 293 static void http_send_auth_request_http_rep_done(struct tevent_req *subreq)
 294 {
 295         struct tevent_req *req =
 296                 tevent_req_callback_data(subreq,
 297                 struct tevent_req);
 298         struct http_auth_state *state =
 299                 tevent_req_data(req,
 300                 struct http_auth_state);
 301         DATA_BLOB gensec_in = data_blob_null;
 302         NTSTATUS status;
 303
 304         status = http_read_response_recv(subreq, state,
 305                                          &state->auth_response);
 306         TALLOC_FREE(subreq);
 307         if (tevent_req_nterror(req, status)) {
 308                 return;
 309         }
 310
 311         /*
 312          * We we asked for up to UINT16_MAX bytes of
 313          * content, we don't expect
 314          * state->auth_response->remaining_content_length
 315          * to be set.
 316          *
 317          * For now we just ignore any bytes in
 318          * state->auth_response->body.
 319          */
 320         if (state->auth_response->remaining_content_length != 0) {
 321                 tevent_req_nterror(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
 322                 return;
 323         }
 324
 325         status = http_parse_auth_response(state->auth,
 326                                           state->auth_response,
 327                                           &gensec_in);
 328         if (tevent_req_nterror(req, status)) {
 329                 return;
 330         }
 331
 332         subreq = gensec_update_send(state, state->ev,
 333                                     state->gensec_ctx,
 334                                     gensec_in);
 335         if (tevent_req_nomem(subreq, req)) {
 336                 return;
 337         }
 338         tevent_req_set_callback(subreq, http_send_auth_request_gensec_done, req);
 339 }
 340
 341 NTSTATUS http_send_auth_request_recv(struct tevent_req *req)
 342 {
 343         NTSTATUS status;
 344
 345         if (tevent_req_is_nterror(req, &status)) {
 346                 tevent_req_received(req);
 347                 return status;
 348         }
 349         tevent_req_received(req);
 350
 351         return NT_STATUS_OK;
 352 }