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                 int cmp;
  65
  66                 cmp = strcasecmp(h->key, "WWW-Authenticate");
  67                 if (cmp != 0) {
  68                         continue;
  69                 }
  70
  71                 switch (auth) {
  72                 case HTTP_AUTH_NTLM:
  73                         if (strncasecmp(h->value, "NTLM ", 5) == 0) {
  74                                 *in = data_blob_string_const(h->value);
  75                                 return NT_STATUS_OK;
  76                         }
  77                         break;
  78                 default:
  79                         break;
  80                 }
  81         }
  82
  83         return NT_STATUS_NOT_SUPPORTED;
  84 }
  85
  86 struct http_auth_state {
  87         struct tevent_context *ev;
  88
  89         struct tstream_context *stream;
  90         struct tevent_queue *send_queue;
  91
  92         enum http_auth_method auth;
  93
  94         struct gensec_security *gensec_ctx;
  95         NTSTATUS gensec_status;
  96
  97         const struct http_request *original_request;
  98         struct http_request *next_request;
  99         struct http_request *auth_response;
 100 };
 101
 102
 103 static void http_send_auth_request_gensec_done(struct tevent_req *subreq);
 104 static void http_send_auth_request_http_req_done(struct tevent_req *subreq);
 105 static void http_send_auth_request_http_rep_done(struct tevent_req *subreq);
 106
 107 struct tevent_req *http_send_auth_request_send(TALLOC_CTX *mem_ctx,
 108                                                struct tevent_context *ev,
 109                                                struct tstream_context *stream,
 110                                                struct tevent_queue *send_queue,
 111                                                const struct http_request *original_request,
 112                                                struct cli_credentials *credentials,
 113                                                struct loadparm_context *lp_ctx,
 114                                                enum http_auth_method auth)
 115 {
 116         struct tevent_req *req = NULL;
 117         struct http_auth_state *state = NULL;
 118         struct tevent_req *subreq = NULL;
 119         DATA_BLOB gensec_in = data_blob_null;
 120         NTSTATUS status;
 121         const char *mech_name = NULL;
 122
 123         req = tevent_req_create(mem_ctx, &state, struct http_auth_state);
 124         if (req == NULL) {
 125                 return NULL;
 126         }
 127         state->ev = ev;
 128         state->stream = stream;
 129         state->send_queue = send_queue;
 130         state->auth = auth;
 131         state->original_request = original_request;
 132
 133         status = gensec_init();
 134         if (tevent_req_nterror(req, status)) {
 135                 return tevent_req_post(req, ev);
 136         }
 137
 138         status = gensec_client_start(state, &state->gensec_ctx,
 139                                      lpcfg_gensec_settings(state, lp_ctx));
 140         if (tevent_req_nterror(req, status)) {
 141                 return tevent_req_post(req, ev);
 142         }
 143
 144         status = gensec_set_credentials(state->gensec_ctx, credentials);
 145         if (tevent_req_nterror(req, status)) {
 146                 return tevent_req_post(req, ev);
 147         }
 148
 149         switch (state->auth) {
 150         case HTTP_AUTH_BASIC:
 151                 mech_name = "http_basic";
 152                 break;
 153         case HTTP_AUTH_NTLM:
 154                 mech_name = "http_ntlm";
 155                 break;
 156         default:
 157                 tevent_req_nterror(req, NT_STATUS_NOT_SUPPORTED);
 158                 return tevent_req_post(req, ev);
 159         }
 160
 161         status = gensec_start_mech_by_name(state->gensec_ctx, mech_name);
 162         if (tevent_req_nterror(req, status)) {
 163                 return tevent_req_post(req, ev);
 164         }
 165
 166         subreq = gensec_update_send(state, state->ev,
 167                                     state->gensec_ctx,
 168                                     gensec_in);
 169         if (tevent_req_nomem(subreq, req)) {
 170                 return tevent_req_post(req, ev);
 171         }
 172         tevent_req_set_callback(subreq, http_send_auth_request_gensec_done, req);
 173
 174         return req;
 175 }
 176
 177 static void http_send_auth_request_gensec_done(struct tevent_req *subreq)
 178 {
 179         struct tevent_req *req =
 180                 tevent_req_callback_data(subreq,
 181                 struct tevent_req);
 182         struct http_auth_state *state =
 183                 tevent_req_data(req,
 184                 struct http_auth_state);
 185         DATA_BLOB gensec_out = data_blob_null;
 186         NTSTATUS status;
 187         int ret;
 188
 189         TALLOC_FREE(state->auth_response);
 190
 191         status = gensec_update_recv(subreq, state, &gensec_out);
 192         TALLOC_FREE(subreq);
 193         state->gensec_status = status;
 194         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 195                 status = NT_STATUS_OK;
 196         }
 197         if (tevent_req_nterror(req, status)) {
 198                 return;
 199         }
 200
 201         state->next_request = talloc_zero(state, struct http_request);
 202         if (tevent_req_nomem(state->next_request, req)) {
 203                 return;
 204         }
 205
 206         status = http_copy_header(state->original_request, state->next_request);
 207         if (tevent_req_nterror(req, status)) {
 208                 return;
 209         }
 210
 211         if (!NT_STATUS_IS_OK(state->gensec_status)) {
 212                 /*
 213                  * More preprocessing required before we
 214                  * can include the content.
 215                  */
 216                 ret = http_replace_header(state->next_request,
 217                                           &state->next_request->headers,
 218                                           "Content-Length", "0");
 219                 if (ret != 0) {
 220                         tevent_req_oom(req);
 221                         return;
 222                 }
 223         } else {
 224                 state->next_request->body = state->original_request->body;
 225         }
 226
 227         if (gensec_out.length > 0) {
 228                 ret = http_add_header(state->next_request,
 229                                       &state->next_request->headers,
 230                                       "Authorization",
 231                                       (char *)gensec_out.data);
 232                 if (ret != 0) {
 233                         tevent_req_oom(req);
 234                         return;
 235                 }
 236                 data_blob_free(&gensec_out);
 237         }
 238
 239         subreq = http_send_request_send(state, state->ev,
 240                                         state->stream,
 241                                         state->send_queue,
 242                                         state->next_request);
 243         if (tevent_req_nomem(subreq, req)) {
 244                 return;
 245         }
 246         tevent_req_set_callback(subreq,
 247                                 http_send_auth_request_http_req_done,
 248                                 req);
 249 }
 250
 251 static void http_send_auth_request_http_req_done(struct tevent_req *subreq)
 252 {
 253         struct tevent_req *req =
 254                 tevent_req_callback_data(subreq,
 255                 struct tevent_req);
 256         struct http_auth_state *state =
 257                 tevent_req_data(req,
 258                 struct http_auth_state);
 259         NTSTATUS status;
 260
 261         TALLOC_FREE(state->next_request);
 262
 263         status = http_send_request_recv(subreq);
 264         TALLOC_FREE(subreq);
 265         if (tevent_req_nterror(req, status)) {
 266                 return;
 267         }
 268
 269         /*
 270          * If no more processing required, it is done
 271          *
 272          * The caller will use http_read_response_send/recv
 273          * in order to get the high level response.
 274          */
 275         if (NT_STATUS_IS_OK(state->gensec_status)) {
 276                 tevent_req_done(req);
 277                 return;
 278         }
 279
 280         /*
 281          * If more processing required, read the response from server
 282          *
 283          * We may get an empty RPCH Echo packet from the server
 284          * on the "RPC_OUT_DATA" path. We need to consume this
 285          * from the socket, but for now we just ignore the bytes.
 286          */
 287         subreq = http_read_response_send(state, state->ev,
 288                                          state->stream,
 289                                          UINT16_MAX);
 290         if (tevent_req_nomem(subreq, req)) {
 291                 return;
 292         }
 293         tevent_req_set_callback(subreq,
 294                                 http_send_auth_request_http_rep_done,
 295                                 req);
 296 }
 297
 298 static void http_send_auth_request_http_rep_done(struct tevent_req *subreq)
 299 {
 300         struct tevent_req *req =
 301                 tevent_req_callback_data(subreq,
 302                 struct tevent_req);
 303         struct http_auth_state *state =
 304                 tevent_req_data(req,
 305                 struct http_auth_state);
 306         DATA_BLOB gensec_in = data_blob_null;
 307         NTSTATUS status;
 308
 309         status = http_read_response_recv(subreq, state,
 310                                          &state->auth_response);
 311         TALLOC_FREE(subreq);
 312         if (tevent_req_nterror(req, status)) {
 313                 return;
 314         }
 315
 316         /*
 317          * We we asked for up to UINT16_MAX bytes of
 318          * content, we don't expect
 319          * state->auth_response->remaining_content_length
 320          * to be set.
 321          *
 322          * For now we just ignore any bytes in
 323          * state->auth_response->body.
 324          */
 325         if (state->auth_response->remaining_content_length != 0) {
 326                 tevent_req_nterror(req, NT_STATUS_INVALID_NETWORK_RESPONSE);
 327                 return;
 328         }
 329
 330         status = http_parse_auth_response(state->auth,
 331                                           state->auth_response,
 332                                           &gensec_in);
 333         if (tevent_req_nterror(req, status)) {
 334                 return;
 335         }
 336
 337         subreq = gensec_update_send(state, state->ev,
 338                                     state->gensec_ctx,
 339                                     gensec_in);
 340         if (tevent_req_nomem(subreq, req)) {
 341                 return;
 342         }
 343         tevent_req_set_callback(subreq, http_send_auth_request_gensec_done, req);
 344 }
 345
 346 NTSTATUS http_send_auth_request_recv(struct tevent_req *req)
 347 {
 348         NTSTATUS status;
 349
 350         if (tevent_req_is_nterror(req, &status)) {
 351                 tevent_req_received(req);
 352                 return status;
 353         }
 354         tevent_req_received(req);
 355
 356         return NT_STATUS_OK;
 357 }