test/simline/http.c

   1 #ifndef _XOPEN_SOURCE
   2 #include "../../config.h"
   3 #define _XOPEN_SOURCE XOPEN_SOURCE_LEVEL_FOR_STRDUP
   4 #endif
   5
   6 #include "http.h"
   7 #include "../test-tools.h"
   8 #include <stdlib.h>
   9 #include <errno.h>
  10 #include <unistd.h>
  11 #include <string.h>
  12 #include <stdio.h> /* fprintf() */
  13 #include <limits.h>
  14 #include <string.h> /* strdup() */
  15 #include <strings.h> /* strcasecmp() */
  16 #include <stdint.h> /* int8_t */
  17 #include <stddef.h> /* size_t, NULL */
  18 #include <ctype.h> /* isprint() */
  19 #include <sys/socket.h> /* MSG_NOSIGNAL for http_send_callback() */
  20
  21 /*
  22 Base64 encoder is part of the libb64 project, and has been placed in the public domain.
  23 For details, see http://sourceforge.net/projects/libb64
  24 It's copy of ../../src/cencode.c due to symbol names.
  25 */
  26
  27
  28 typedef enum {
  29         step_A, step_B, step_C
  30 } base64_encodestep;
  31
  32 typedef struct {
  33         base64_encodestep step;
  34         int8_t result;
  35         int stepcount; /* number of encoded octet triplets on a line,
  36                       or -1 to for end-less line */
  37 } base64_encodestate;
  38
  39 static const int CHARS_PER_LINE = 72;
  40
  41 /* Initialize Base64 coder.
  42  * @one_line is false for multi-line MIME encoding,
  43  * true for endless one-line format. */
  44 static void base64_init_encodestate(base64_encodestate* state_in, _Bool one_line) {
  45         state_in->step = step_A;
  46         state_in->result = 0;
  47         state_in->stepcount = (one_line) ? -1 : 0;
  48 }
  49
  50
  51 static int8_t base64_encode_value(int8_t value_in) {
  52     /* XXX: CHAR_BIT == 8 because of <stdint.h> */
  53         static const int8_t encoding[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  54         if (value_in > 63) return '=';
  55         return encoding[value_in];
  56 }
  57
  58
  59 static size_t base64_encode_block(const int8_t* plaintext_in,
  60         size_t length_in, int8_t *code_out, base64_encodestate* state_in) {
  61         const int8_t *plainchar = plaintext_in;
  62         const int8_t* const plaintextend = plaintext_in + length_in;
  63         int8_t *codechar = code_out;
  64         int8_t result;
  65         int8_t fragment;
  66
  67         result = state_in->result;
  68
  69         switch (state_in->step) {
  70                 while (1) {
  71         case step_A:
  72                         if (plainchar == plaintextend) {
  73                                 state_in->result = result;
  74                                 state_in->step = step_A;
  75                                 return codechar - code_out;
  76                         }
  77                         fragment = *plainchar++;
  78                         result = (fragment & 0x0fc) >> 2;
  79                         *codechar++ = base64_encode_value(result);
  80                         result = (fragment & 0x003) << 4;
  81         case step_B:
  82                         if (plainchar == plaintextend) {
  83                                 state_in->result = result;
  84                                 state_in->step = step_B;
  85                                 return codechar - code_out;
  86                         }
  87                         fragment = *plainchar++;
  88                         result |= (fragment & 0x0f0) >> 4;
  89                         *codechar++ = base64_encode_value(result);
  90                         result = (fragment & 0x00f) << 2;
  91         case step_C:
  92                         if (plainchar == plaintextend) {
  93                                 state_in->result = result;
  94                                 state_in->step = step_C;
  95                                 return codechar - code_out;
  96                         }
  97                         fragment = *plainchar++;
  98                         result |= (fragment & 0x0c0) >> 6;
  99                         *codechar++ = base64_encode_value(result);
 100                         result  = (fragment & 0x03f) >> 0;
 101                         *codechar++ = base64_encode_value(result);
 102
 103             if (state_in->stepcount >= 0) {
 104                 ++(state_in->stepcount);
 105                 if (state_in->stepcount == CHARS_PER_LINE/4) {
 106                     *codechar++ = '\n';
 107                     state_in->stepcount = 0;
 108                 }
 109             }
 110                 } /* while */
 111         } /* switch */
 112
 113         /* control should not reach here */
 114         return codechar - code_out;
 115 }
 116
 117
 118 static size_t base64_encode_blockend(int8_t *code_out,
 119         base64_encodestate* state_in) {
 120         int8_t *codechar = code_out;
 121
 122         switch (state_in->step) {
 123         case step_B:
 124                 *codechar++ = base64_encode_value(state_in->result);
 125                 *codechar++ = '=';
 126                 *codechar++ = '=';
 127                 break;
 128         case step_C:
 129                 *codechar++ = base64_encode_value(state_in->result);
 130                 *codechar++ = '=';
 131                 break;
 132         case step_A:
 133                 break;
 134         }
 135     if (state_in->stepcount >= 0)
 136         *codechar++ = '\n';
 137
 138         return codechar - code_out;
 139 }
 140
 141
 142 /* Encode given data into MIME Base64 encoded zero terminated string.
 143  * @plain are input data (binary stream)
 144  * @length is length of @plain data in bytes
 145  * @one_line is false for multi-line MIME encoding,
 146  * true for endless one-line format.
 147  * @return allocated string of base64 encoded plain data or NULL in case of
 148  * error. You must free it. */
 149 /* TODO: Allow one-line format */
 150 static char *base64encode(const void *plain, const size_t length,
 151         _Bool one_line) {
 152
 153     base64_encodestate state;
 154     size_t code_length;
 155     char *buffer, *new_buffer;
 156
 157     if (!plain) {
 158         if (length) return NULL;
 159         /* Empty input is valid input */
 160         plain = "";
 161     }
 162
 163     base64_init_encodestate(&state, one_line);
 164
 165     /* Allocate buffer
 166      * (4 is padding, 1 is final new line, and 1 is string terminator) */
 167     buffer = malloc(length * 2 + 4 + 1 + 1);
 168     if (!buffer) return NULL;
 169
 170     /* Encode plain data */
 171     code_length = base64_encode_block(plain, length, (int8_t *)buffer,
 172             &state);
 173     code_length += base64_encode_blockend(((int8_t*)buffer) + code_length,
 174             &state);
 175
 176     /* Terminate string */
 177     buffer[code_length++] = '\0';
 178
 179     /* Shrink the buffer */
 180     new_buffer = realloc(buffer, code_length);
 181     if (new_buffer) buffer = new_buffer;
 182
 183     return buffer;
 184 }
 185
 186
 187 /* Convert hexadecimal digit to integer. Return negative value if charcter is
 188  * not valid hexadecimal digit. */
 189 static int hex2i(char digit) {
 190     if (digit >= '0' && digit <= '9')
 191         return digit - '0';
 192     if (digit >= 'a' && digit <= 'f')
 193         return digit - 'a' + 10;
 194     if (digit >= 'A' && digit <= 'F')
 195         return digit - 'A' + 10;
 196     return -1;
 197 }
 198
 199
 200 /* Decode URI-coded string.
 201  * @return allocated decoded string or NULL in case of error. */
 202 static char *uri_decode(const char *coded) {
 203     char *plain, *p;
 204     int digit1, digit2;
 205
 206     if (coded == NULL) return NULL;
 207     plain = malloc(strlen(coded) + 1);
 208     if (plain == NULL) return NULL;
 209
 210     for (p = plain; *coded != '\0'; p++, coded++) {
 211         if (*coded == '%') {
 212             digit1 = hex2i(coded[1]);
 213             if (digit1 < 0) {
 214                 free(plain);
 215                 return NULL;
 216             }
 217             digit2 = hex2i(coded[2]);
 218             if (digit2< 0) {
 219                 free(plain);
 220                 return NULL;
 221             }
 222             *plain = (digit1 << 4) + digit2;
 223             coded += 2;
 224         } else {
 225             *p = *coded;
 226         }
 227     }
 228     *p = '\0';
 229
 230     return plain;
 231 }
 232
 233
 234 /* Read a line from HTTP socket.
 235  * @connection is HTTP connection to read from.
 236  * @line is auto-reallocated just read line. Will be NULL if EOF has been
 237  * reached or error occured.
 238  * @buffer is automatically reallocated buffer for the socket. It can preserve
 239  * prematurately read socket data.
 240  * @buffer_size is allocated size of @buffer
 241  * @buffer_length is size of head of the buffer that holds read data.
 242  * @return 0 in success. */
 243 static int http_read_line(const struct http_connection *connection,
 244         char **line, char **buffer, size_t *buffer_size,
 245         size_t *buffer_used) {
 246     ssize_t got;
 247     char *p, *tmp;
 248
 249     if (line == NULL) return HTTP_ERROR_SERVER;
 250     free(*line);
 251     *line = NULL;
 252
 253     if (connection == NULL || connection->recv_callback == NULL)
 254         return HTTP_ERROR_SERVER;
 255     if (buffer == NULL || buffer_size == NULL || buffer_used == NULL)
 256         return HTTP_ERROR_SERVER;
 257     if (*buffer == NULL && *buffer_size > 0) return HTTP_ERROR_SERVER;
 258     if (*buffer_size < *buffer_used) return HTTP_ERROR_SERVER;
 259
 260 #define BURST 1024
 261     while (1) {
 262         /* Check for EOL */
 263         for (p = *buffer; p < *buffer + *buffer_used; p++)
 264         {
 265             if (*p != '\r')
 266                 continue;
 267             if (!(p + 1 < *buffer + *buffer_used && p[1] == '\n'))
 268                 continue;
 269
 270             /* EOL found */
 271             /* Crop by zero at EOL */
 272             *p = '\0';
 273             p += 2;
 274             /* Copy read ahead data to new buffer and point line to original
 275              * buffer. */
 276             tmp = malloc(BURST);
 277             if (tmp == NULL) return HTTP_ERROR_SERVER;
 278             memcpy(tmp, p, *buffer + *buffer_used - p);
 279             *line = *buffer;
 280             *buffer_size = BURST;
 281             *buffer_used = *buffer + *buffer_used - p;
 282             *buffer = tmp;
 283             /* And exit */
 284             return HTTP_ERROR_SUCCESS;
 285         }
 286
 287         if (*buffer_size == *buffer_used) {
 288             /* Grow buffer */
 289             tmp = realloc(*buffer, *buffer_size + BURST);
 290             if (tmp == NULL) return HTTP_ERROR_SERVER;
 291             *buffer = tmp;
 292             *buffer_size += BURST;
 293         }
 294
 295         /* Read data */
 296         got = connection->recv_callback(connection, *buffer + *buffer_used,
 297                 *buffer_size - *buffer_used);
 298         if (got == -1) return HTTP_ERROR_CLIENT;
 299
 300         /* Check for EOF */
 301         if (got == 0) return HTTP_ERROR_CLIENT;
 302
 303         /* Move end of buffer */
 304         *buffer_used += got;
 305     }
 306 #undef BURST
 307
 308     return HTTP_ERROR_SERVER;
 309 }
 310
 311
 312 /* Write a bulk data into HTTP socket.
 313  * @connection is HTTP connection to write to.
 314  * @data are bitstream to send to client.
 315  * @length is size of @data in bytes.
 316  * @return 0 in success. */
 317 static int http_write_bulk(const struct http_connection *connection,
 318         const void *data, size_t length) {
 319     ssize_t written;
 320     const void *end;
 321
 322     if (connection == NULL || connection->send_callback == NULL)
 323         return HTTP_ERROR_SERVER;
 324     if (data == NULL && length > 0) return HTTP_ERROR_SERVER;
 325
 326     for (end = data + length; data != end; data += written, length -= written) {
 327         written = connection->send_callback(connection, data, length);
 328         if (written == -1) return HTTP_ERROR_CLIENT;
 329     }
 330
 331     return HTTP_ERROR_SUCCESS;
 332 }
 333
 334
 335 /* Write a line into HTTP socket.
 336  * @connection is HTTP connection to write to.
 337  * @line is NULL terminated string to send to client. HTTP EOL will be added.
 338  * @return 0 in success. */
 339 static int http_write_line(const struct http_connection *connection,
 340         const char *line) {
 341     int error;
 342     if (line == NULL) return HTTP_ERROR_SERVER;
 343
 344     fprintf(stderr, "Response: <%s>\n", line);
 345
 346     /* Send the line */
 347     if ((error = http_write_bulk(connection, line, strlen(line))))
 348         return error;
 349
 350     /* Send EOL */
 351     if ((error = http_write_bulk(connection, "\r\n", 2)))
 352         return error;
 353
 354     return HTTP_ERROR_SUCCESS;
 355 }
 356
 357
 358 /* Read data of given length from HTTP socket.
 359  * @connection is HTTP connection to read from.
 360  * @data is auto-allocated just read data bulk. Will be NULL if EOF has been
 361  * reached or error occured.
 362  * @data_length is size of bytes to read.
 363  * @buffer is automatically reallocated buffer for the socket. It can preserve
 364  * prematurately read socket data.
 365  * @buffer_size is allocated size of @buffer
 366  * @buffer_length is size of head of the buffer that holds read data.
 367  * @return 0 in success. */
 368 static int http_read_bulk(const struct http_connection *connection,
 369         void **data, size_t data_length,
 370         char **buffer, size_t *buffer_size, size_t *buffer_used) {
 371     ssize_t got;
 372     char *tmp;
 373
 374     if (data == NULL) return HTTP_ERROR_SERVER;
 375     *data = NULL;
 376
 377     if (connection == NULL || connection->recv_callback == NULL)
 378         return HTTP_ERROR_SERVER;
 379     if (buffer == NULL || buffer_size == NULL || buffer_used == NULL)
 380         return HTTP_ERROR_SERVER;
 381     if (*buffer == NULL && *buffer_size > 0) return HTTP_ERROR_SERVER;
 382     if (*buffer_size < *buffer_used) return HTTP_ERROR_SERVER;
 383
 384     if (data_length <= 0) return HTTP_ERROR_SUCCESS;
 385
 386 #define BURST 1024
 387     while (1) {
 388         /* Check whether enought data have been read */
 389         if (*buffer_used >= data_length) {
 390             /* Copy read ahead data to new buffer and point data to original
 391              * buffer. */
 392             tmp = malloc(BURST);
 393             if (tmp == NULL) return HTTP_ERROR_SERVER;
 394             memcpy(tmp, *buffer + data_length, *buffer_used - data_length);
 395             *data = *buffer;
 396             *buffer_size = BURST;
 397             *buffer_used = *buffer_used - data_length;
 398             *buffer = tmp;
 399             /* And exit */
 400             return HTTP_ERROR_SUCCESS;
 401         }
 402
 403         if (*buffer_size == *buffer_used) {
 404             /* Grow buffer */
 405             tmp = realloc(*buffer, *buffer_size + BURST);
 406             if (tmp == NULL) return HTTP_ERROR_SERVER;
 407             *buffer = tmp;
 408             *buffer_size += BURST;
 409         }
 410
 411         /* Read data */
 412         got = connection->recv_callback(connection, *buffer + *buffer_used,
 413                 *buffer_size - *buffer_used);
 414         if (got == -1) return HTTP_ERROR_CLIENT;
 415
 416         /* Check for EOF */
 417         if (got == 0) return HTTP_ERROR_CLIENT;
 418
 419         /* Move end of buffer */
 420         *buffer_used += got;
 421     }
 422 #undef BURST
 423
 424     return HTTP_ERROR_SERVER;
 425 }
 426
 427
 428 /* Parse HTTP request header.
 429  * @request is pre-allocated HTTP request.
 430  * @return 0 if success. */
 431 static int http_parse_request_header(char *line,
 432         struct http_request *request) {
 433     char *p;
 434
 435     fprintf(stderr, "Request: <%s>\n", line);
 436
 437     /* Get method */
 438     p = strchr(line, ' ');
 439     if (p == NULL) return HTTP_ERROR_SERVER;
 440     *p = '\0';
 441     if (!strcmp(line, "GET"))
 442         request->method = HTTP_METHOD_GET;
 443     else if (!strcmp(line, "POST"))
 444         request->method = HTTP_METHOD_POST;
 445     else
 446         request->method = HTTP_METHOD_UNKNOWN;
 447     line = p + 1;
 448
 449     /* Get URI */
 450     p = strchr(line, ' ');
 451     if (p != NULL) *p = '\0';
 452     request->uri = uri_decode(line);
 453     if (request->uri == NULL) return HTTP_ERROR_SERVER;
 454
 455     /* Do not care about HTTP version */
 456
 457     fprintf(stderr, "Request-URI: <%s>\n", request->uri);
 458     return HTTP_ERROR_SUCCESS;
 459 }
 460
 461
 462 /* Send HTTP response status line to client.
 463  * @return 0 if success. */
 464 static int http_write_response_status(const struct http_connection *connection,
 465         const struct http_response *response) {
 466     char *buffer = NULL;
 467     int error;
 468
 469     if (response == NULL) return HTTP_ERROR_SERVER;
 470
 471     if (-1 == test_asprintf(&buffer, "HTTP/1.0 %u %s", response->status,
 472                 (response->reason == NULL) ? "" : response->reason))
 473         return HTTP_ERROR_SERVER;
 474     error = http_write_line(connection, buffer);
 475     free(buffer);
 476
 477     return error;
 478 }
 479
 480
 481 /* Parse generic HTTP header.
 482  * @request is pre-allocated HTTP request.
 483  * @return 0 if success, negative value if internal error, positive value if
 484  * header is not valid. */
 485 static int http_parse_header(char *line, struct http_request *request) {
 486     struct http_header *header;
 487
 488     if (line == NULL || request == NULL) return HTTP_ERROR_SERVER;
 489
 490     fprintf(stderr, "Header: <%s>\n", line);
 491
 492     /* Find last used header */
 493     for (header = request->headers; header != NULL && header->next != NULL;
 494             header = header->next);
 495
 496     if (*line == ' ' || *line == '\t') {
 497         /* Line is continuation of last header */
 498         if (header == NULL)
 499             return HTTP_ERROR_CLIENT;   /* No previous header to continue */
 500         line++;
 501         size_t old_length = strlen(header->value);
 502         char *tmp = realloc(header->value,
 503                 sizeof(header->value[0]) * (old_length + strlen(line) + 1));
 504         if (tmp == NULL) return HTTP_ERROR_SERVER;
 505         header->value = tmp;
 506         strcpy(&header->value[old_length], line);
 507     } else {
 508         /* New header */
 509         struct http_header *new_header = calloc(sizeof(*new_header), 1);
 510         if (new_header == NULL) return HTTP_ERROR_SERVER;
 511
 512         char *p = strstr(line, ": ");
 513         if (p == NULL) {
 514             http_header_free(&new_header);
 515             return HTTP_ERROR_CLIENT;
 516         }
 517
 518         size_t length = p - line;
 519         new_header->name = malloc(sizeof(line[0]) * (length + 1));
 520         if (new_header->name == NULL) {
 521             http_header_free(&new_header);
 522             return HTTP_ERROR_SERVER;
 523         }
 524         strncpy(new_header->name, line, length);
 525         new_header->name[length] = '\0';
 526
 527         p += 2;
 528         length = strlen(p);
 529         new_header->value = malloc(sizeof(p[0]) * (length + 1));
 530         if (new_header->value == NULL) {
 531             http_header_free(&new_header);
 532             return HTTP_ERROR_SERVER;
 533         }
 534         strcpy(new_header->value, p);
 535
 536         if (request->headers == NULL)
 537             request->headers = new_header;
 538         else
 539             header->next = new_header;
 540     }
 541
 542
 543     /* FIXME: Decode. After parsing all headers as we could decode begining
 544      * and then got encoded continuation. */
 545     return HTTP_ERROR_SUCCESS;
 546 }
 547
 548
 549 /* Send HTTP header to client.
 550  * @return 0 if success. */
 551 static int http_write_header(const struct http_connection *connection,
 552         const struct http_header *header) {
 553     char *buffer = NULL;
 554     int error;
 555
 556     if (header == NULL) return HTTP_ERROR_SERVER;
 557
 558     if (header->name == NULL) return HTTP_ERROR_SERVER;
 559
 560     /* TODO: Quote, split long lines */
 561     if (-1 == test_asprintf(&buffer, "%s: %s", header->name,
 562                 (header->value == NULL) ? "" : header->value))
 563         return HTTP_ERROR_SERVER;
 564     error = http_write_line(connection, buffer);
 565     free(buffer);
 566
 567     return error;
 568 }
 569
 570
 571 /* Find Content-Length value in HTTP request headers and set it into @request.
 572  * @return 0 in success. */
 573 static int find_content_length(struct http_request *request) {
 574     struct http_header *header;
 575     if (request == NULL) return HTTP_ERROR_SERVER;
 576
 577     for (header = request->headers; header != NULL; header = header->next) {
 578         if (header->name == NULL) continue;
 579         if (!strcasecmp(header->name, "Content-Length")) break;
 580     }
 581
 582     if (header != NULL && header->value != NULL) {
 583         char *p;
 584         long long int value = strtoll(header->value, &p, 10);
 585         if (*p != '\0')
 586             return HTTP_ERROR_CLIENT;
 587         if ((value == LLONG_MIN || value == LLONG_MAX) && errno == ERANGE)
 588             return HTTP_ERROR_SERVER;
 589         if (value < 0)
 590             return HTTP_ERROR_CLIENT;
 591         if ((unsigned long long)value > SIZE_MAX)
 592             return HTTP_ERROR_SERVER;
 593         request->body_length = value;
 594     } else {
 595         request->body_length = 0;
 596     }
 597     return HTTP_ERROR_SUCCESS;
 598 }
 599
 600
 601 /* Print binary stream to STDERR with some escapes */
 602 static void dump_body(const void *data, size_t length) {
 603     fprintf(stderr, "===BEGIN BODY===\n");
 604     if (length > 0 && NULL != data) {
 605         for (size_t i = 0; i < length; i++) {
 606             if (isprint(((const unsigned char *)data)[i]))
 607                 fprintf(stderr, "%c", ((const unsigned char *)data)[i]);
 608             else
 609                 fprintf(stderr, "\\x%02x", ((const unsigned char*)data)[i]);
 610         }
 611         fprintf(stderr, "\n");
 612     }
 613     fprintf(stderr, "===END BODY===\n");
 614 }
 615
 616
 617 /* Read a HTTP request from connection.
 618  * @http_request is heap-allocated received HTTP request,
 619  * or NULL in case of error.
 620  * @return http_error code. */
 621 http_error http_read_request(const struct http_connection *connection,
 622         struct http_request **request) {
 623     char *line = NULL;
 624     char *buffer = NULL;
 625     size_t buffer_size = 0, buffer_used = 0;
 626     int error;
 627
 628     if (request == NULL) return HTTP_ERROR_SERVER;
 629
 630     *request = calloc(1, sizeof(**request));
 631     if (*request == NULL) return HTTP_ERROR_SERVER;
 632
 633     /* Get request header */
 634     if ((error = http_read_line(connection, &line, &buffer, &buffer_size,
 635                 &buffer_used)))
 636         goto leave;
 637     if ((error = http_parse_request_header(line, *request)))
 638         goto leave;
 639
 640     /* Get other headers */
 641     while (1) {
 642         if ((error = http_read_line(connection, &line, &buffer, &buffer_size,
 643                     &buffer_used))) {
 644             fprintf(stderr, "Error while reading HTTP request line\n");
 645             goto leave;
 646         }
 647
 648         /* Check for headers delimiter */
 649         if (line == NULL || *line == '\0') {
 650             break;
 651         }
 652
 653         if ((error = http_parse_header(line, *request))) {
 654             fprintf(stderr, "Error while parsing HTTP request line: <%s>\n",
 655                     line);
 656             goto leave;
 657         }
 658     };
 659
 660     /* Get body */
 661     if ((error = find_content_length(*request))) {
 662         fprintf(stderr, "Could not determine length of body\n");
 663         goto leave;
 664     }
 665     if ((error = http_read_bulk(connection,
 666                     &(*request)->body, (*request)->body_length,
 667                     &buffer, &buffer_size, &buffer_used))) {
 668         fprintf(stderr, "Could not read request body\n");
 669         goto leave;
 670     }
 671     fprintf(stderr, "Body of size %zu B has been received:\n",
 672             (*request)->body_length);
 673     dump_body((*request)->body, (*request)->body_length);
 674
 675 leave:
 676     free(line);
 677     free(buffer);
 678     if (error) http_request_free(request);
 679     return error;
 680 }
 681
 682
 683 /* Write a HTTP response to connection. Auto-add Content-Length header.
 684  * @return 0 in case of success. */
 685 int http_write_response(const struct http_connection *connection,
 686         const struct http_response *response) {
 687     char *buffer = NULL;
 688     int error = -1;
 689
 690     if (response == NULL) return HTTP_ERROR_SERVER;
 691
 692     /* Status line */
 693     error = http_write_response_status(connection, response);
 694     if (error) return error;
 695
 696     /* Headers */
 697     for (struct http_header *header = response->headers; header != NULL;
 698             header = header->next) {
 699         error = http_write_header(connection, header);
 700         if (error) return error;
 701     }
 702     if (-1 == test_asprintf(&buffer, "Content-Length: %u",
 703                 response->body_length))
 704         return HTTP_ERROR_SERVER;
 705     error = http_write_line(connection, buffer);
 706     if (error) return error;
 707
 708     /* Headers trailer */
 709     error = http_write_line(connection, "");
 710     if (error) return error;
 711
 712     /* Body */
 713     if (response->body_length > 0) {
 714         error = http_write_bulk(connection, response->body,
 715                 response->body_length);
 716         if (error) return error;
 717     }
 718     fprintf(stderr, "Body of size %zu B has been sent:\n",
 719             response->body_length);
 720     dump_body(response->body, response->body_length);
 721
 722     free(buffer);
 723     return HTTP_ERROR_SUCCESS;
 724 }
 725
 726
 727 /* Build Set-Cookie header. In case of error, return NULL. Caller must free
 728  * the header. */
 729 static struct http_header *http_build_setcookie_header (
 730         const char *cokie_name, const char *cookie_value,
 731         const char *cookie_domain, const char *cookie_path) {
 732     struct http_header *header = NULL;
 733     char *domain_parameter = NULL;
 734     char *path_parameter = NULL;
 735
 736     if (cokie_name == NULL) goto error;
 737
 738     header = calloc(1, sizeof(*header));
 739     if (header == NULL) goto error;
 740
 741     header->name = strdup("Set-Cookie");
 742     if (header->name == NULL) goto error;
 743
 744     if (cookie_domain != NULL)
 745         if (-1 == test_asprintf(&domain_parameter, "; Domain=%s",
 746                     cookie_domain))
 747             goto error;
 748
 749     if (cookie_path != NULL)
 750         if (-1 == test_asprintf(&path_parameter, "; Path=%s",
 751                     cookie_path))
 752             goto error;
 753
 754     if (-1 == test_asprintf(&header->value, "%s=%s%s%s",
 755                 cokie_name,
 756                 (cookie_value == NULL) ? "" : cookie_value,
 757                 (domain_parameter == NULL) ? "": domain_parameter,
 758                 (path_parameter == NULL) ? "": path_parameter))
 759         goto error;
 760     goto ok;
 761
 762 error:
 763     http_header_free(&header);
 764 ok:
 765     free(domain_parameter);
 766     free(path_parameter);
 767     return header;
 768 }
 769
 770
 771 /* Send a 200 Ok response with a cookie */
 772 int http_send_response_200_cookie(const struct http_connection *connection,
 773         const char *cokie_name, const char *cookie_value,
 774         const char *cookie_domain, const char *cookie_path,
 775         const void *body, size_t body_length, const char *type) {
 776     int retval;
 777     struct http_header *header_cookie = NULL;
 778     struct http_header header_contenttype = {
 779         .name = "Content-Type",
 780         .value = (char *)type,
 781         .next = NULL
 782     };
 783     struct http_response response = {
 784         .status = 200,
 785         .reason = "OK",
 786         .headers = NULL,
 787         .body_length = body_length,
 788         .body = (void *)body
 789     };
 790
 791     if (cokie_name != NULL) {
 792         if (NULL == (header_cookie = http_build_setcookie_header(
 793                         cokie_name, cookie_value, cookie_domain, cookie_path)))
 794             return http_send_response_500(connection,
 795                     "Could not build Set-Cookie header");
 796     }
 797
 798     /* Link defined headers */
 799     if (type != NULL) {
 800         response.headers = &header_contenttype;
 801     }
 802     if (header_cookie != NULL) {
 803         header_cookie->next = response.headers;
 804         response.headers = header_cookie;
 805     }
 806
 807     retval = http_write_response(connection, &response);
 808     http_header_free(&header_cookie);
 809     return retval;
 810 }
 811
 812
 813 /* Send a 200 Ok response */
 814 int http_send_response_200(const struct http_connection *connection,
 815         const void *body, size_t body_length, const char *type) {
 816     return http_send_response_200_cookie(connection,
 817             NULL, NULL, NULL, NULL,
 818             body, body_length, type);
 819 }
 820
 821
 822 /* Send a 302 Found response setting a cookie */
 823 int http_send_response_302_cookie(const struct http_connection *connection,
 824         const char *cokie_name, const char *cookie_value,
 825         const char *cookie_domain, const char *cookie_path,
 826         const char *location) {
 827     int retval;
 828     struct http_header *header_cookie = NULL;
 829     struct http_header header_location = {
 830         .name = "Location",
 831         .value = (char *) location,
 832         .next = NULL
 833     };
 834     struct http_response response = {
 835         .status = 302,
 836         .reason = "Found",
 837         .headers = NULL,
 838         .body_length = 0,
 839         .body = NULL
 840     };
 841
 842     if (cokie_name != NULL) {
 843         if (NULL == (header_cookie = http_build_setcookie_header(
 844                         cokie_name, cookie_value, cookie_domain, cookie_path)))
 845             return http_send_response_500(connection,
 846                     "Could not build Set-Cookie header");
 847     }
 848
 849     /* Link defined headers */
 850     if (location != NULL) {
 851         response.headers = &header_location;
 852     }
 853     if (header_cookie != NULL) {
 854         header_cookie->next = response.headers;
 855         response.headers = header_cookie;
 856     }
 857
 858     retval = http_write_response(connection, &response);
 859     http_header_free(&header_cookie);
 860     return retval;
 861 }
 862
 863
 864 /* Send a 302 Found response with totp authentication scheme header */
 865 int http_send_response_302_totp(const struct http_connection *connection,
 866         const char *code, const char *text, const char *location) {
 867     struct http_header header_code = {
 868         .name = "X-Response-message-code",
 869         .value = (char *) code,
 870         .next = NULL
 871     };
 872     struct http_header header_text = {
 873         .name = "X-Response-message-text",
 874         .value = (char *) text,
 875         .next = NULL
 876     };
 877     struct http_header header_location = {
 878         .name = "Location",
 879         .value = (char *) location,
 880         .next = NULL
 881     };
 882     struct http_response response = {
 883         .status = 302,
 884         .reason = "Found",
 885         .headers = NULL,
 886         .body_length = 0,
 887         .body = NULL
 888     };
 889
 890     /* Link defined headers */
 891     if (location != NULL) {
 892         response.headers = &header_location;
 893     }
 894     if (text != NULL) {
 895         header_text.next = response.headers;
 896         response.headers = &header_text;
 897     }
 898     if (code != NULL) {
 899         header_code.next = response.headers;
 900         response.headers = &header_code;
 901     }
 902
 903     return http_write_response(connection, &response);
 904 }
 905
 906
 907 /* Send a 400 Bad Request response.
 908  * Use non-NULL @reason to override status message. */
 909 int http_send_response_400(const struct http_connection *connection,
 910         const char *reason) {
 911     struct http_response response = {
 912         .status = 400,
 913         .reason = (reason == NULL) ? "Bad Request" : (char *) reason,
 914         .headers = NULL,
 915         .body_length = 0,
 916         .body = NULL
 917     };
 918
 919     return http_write_response(connection, &response);
 920 }
 921
 922
 923 /* Send a 401 Unauthorized response with Basic authentication scheme header */
 924 int http_send_response_401_basic(const struct http_connection *connection) {
 925     struct http_header header = {
 926         .name = "WWW-Authenticate",
 927         .value = "Basic realm=\"SimulatedISDSServer\"",
 928         .next = NULL
 929     };
 930     struct http_response response = {
 931         .status = 401,
 932         .reason = "Unauthorized",
 933         .headers = &header,
 934         .body_length = 0,
 935         .body = NULL
 936     };
 937
 938     return http_write_response(connection, &response);
 939 }
 940
 941
 942 /* Send a 401 Unauthorized response with OTP authentication scheme header for
 943  * given @method. */
 944 int http_send_response_401_otp(const struct http_connection *connection,
 945         const char *method, const char *code, const char *text) {
 946     int retval;
 947     struct http_header header = {
 948         .name = "WWW-Authenticate",
 949         .value = NULL,
 950         .next = NULL
 951     };
 952     struct http_header header_code = {
 953         .name = "X-Response-message-code",
 954         .value = (char *) code,
 955         .next = NULL
 956     };
 957     struct http_header header_text = {
 958         .name = "X-Response-message-text",
 959         .value = (char *) text,
 960         .next = NULL
 961     };
 962     struct http_response response = {
 963         .status = 401,
 964         .reason = "Unauthorized",
 965         .headers = &header,
 966         .body_length = 0,
 967         .body = NULL
 968     };
 969
 970     if (-1 == test_asprintf(&header.value, "%s realm=\"SimulatedISDSServer\"",
 971                 method)) {
 972         return http_send_response_500(connection,
 973                 "Could not build WWW-Authenticate header value");
 974     }
 975
 976     /* Link defined headers */
 977     if (code != NULL) header.next = &header_code;
 978     if (text != NULL) {
 979         if (code != NULL)
 980             header_code.next = &header_text;
 981         else
 982             header.next = &header_text;
 983     }
 984
 985     retval = http_write_response(connection, &response);
 986     free(header.value);
 987     return retval;
 988 }
 989
 990
 991 /* Send a 403 Forbidden response */
 992 int http_send_response_403(const struct http_connection *connection) {
 993     struct http_response response = {
 994         .status = 403,
 995         .reason = "Forbidden",
 996         .headers = NULL,
 997         .body_length = 0,
 998         .body = NULL
 999     };
1000
1001     return http_write_response(connection, &response);
1002 }
1003
1004
1005 /* Send a 500 Internal Server Error response.
1006  * Use non-NULL @reason to override status message. */
1007 int http_send_response_500(const struct http_connection *connection,
1008         const char *reason) {
1009     struct http_response response = {
1010         .status = 500,
1011         .reason = (NULL == reason) ? "Internal Server Error" : (char *) reason,
1012         .headers = NULL,
1013         .body_length = 0,
1014         .body = NULL
1015     };
1016
1017     return http_write_response(connection, &response);
1018 }
1019
1020
1021 /* Send a 503 Service Temporarily Unavailable response */
1022 int http_send_response_503(const struct http_connection *connection,
1023         const void *body, size_t body_length, const char *type) {
1024     struct http_header header = {
1025         .name = "Content-Type",
1026         .value = (char *)type
1027     };
1028     struct http_response response = {
1029         .status = 503,
1030         .reason = "Service Temporarily Unavailable",
1031         .headers = (type == NULL) ? NULL : &header,
1032         .body_length = body_length,
1033         .body = (void *)body
1034     };
1035
1036     return http_write_response(connection, &response);
1037 }
1038
1039
1040 /* Returns Authorization header in given request */
1041 static const struct http_header *find_authorization(
1042         const struct http_request *request) {
1043     const struct http_header *header;
1044     if (request == NULL) return NULL;
1045     for (header = request->headers; header != NULL; header = header->next) {
1046         if (header->name != NULL &&
1047                 !strcasecmp(header->name, "Authorization"))
1048             break;
1049     }
1050     return header;
1051 }
1052
1053
1054 /* Return true if request carries Authorization header */
1055 int http_client_authenticates(const struct http_request *request) {
1056     if (find_authorization(request))
1057         return 1;
1058     else
1059         return 0;
1060 }
1061
1062
1063 /* Return HTTP_ERROR_SUCCESS if request carries valid Basic credentials.
1064  * NULL @username or @password equales to empty string. */
1065 http_error http_authenticate_basic(const struct http_request *request,
1066         const char *username, const char *password) {
1067     const struct http_header *header;
1068     const char *basic_cookie_client;
1069     char *basic_cookie_plain = NULL, *basic_cookie_encoded = NULL;
1070     _Bool is_valid;
1071
1072     header = find_authorization(request);
1073     if (header == NULL) return HTTP_ERROR_CLIENT;
1074
1075     if (strncmp(header->value, "Basic ", 6)) return HTTP_ERROR_CLIENT;
1076     basic_cookie_client = header->value + 6;
1077
1078     if (-1 == test_asprintf(&basic_cookie_plain, "%s:%s",
1079                 (username == NULL) ? "" : username,
1080                 (password == NULL) ? "" : password)) {
1081         return HTTP_ERROR_SERVER;
1082     }
1083
1084     basic_cookie_encoded = base64encode(basic_cookie_plain,
1085             strlen(basic_cookie_plain), 1);
1086     if (basic_cookie_encoded == NULL) {
1087         free(basic_cookie_plain);
1088         return HTTP_ERROR_SERVER;
1089     }
1090
1091     fprintf(stderr, "Authenticating basic: got=<%s>, expected=<%s> (%s)\n",
1092             basic_cookie_client, basic_cookie_encoded, basic_cookie_plain);
1093     free(basic_cookie_plain);
1094
1095     is_valid = !strcmp(basic_cookie_encoded, basic_cookie_client);
1096     free(basic_cookie_encoded);
1097
1098     return (is_valid) ? HTTP_ERROR_SUCCESS : HTTP_ERROR_CLIENT;
1099 }
1100
1101
1102 /* Return HTTP_ERROR_SUCCESS if request carries valid OTP credentials.
1103  * NULL @username or @password or @otp equal to empty string. */
1104 http_error http_authenticate_otp(const struct http_request *request,
1105         const char *username, const char *password, const char *otp) {
1106     char *basic_password = NULL;
1107     http_error retval;
1108
1109     /* Concatenate password and OTP code */
1110     if (-1 == test_asprintf(&basic_password, "%s%s",
1111                 (password == NULL) ? "": password,
1112                 (otp == NULL) ? "" : otp)) {
1113         return HTTP_ERROR_SERVER;
1114     }
1115
1116     /* Use Basic authentication */
1117     /* XXX: Specification does not define authorization method string */
1118     retval = http_authenticate_basic(request, username, basic_password);
1119
1120     free(basic_password);
1121     return retval;
1122 }
1123
1124
1125 /* Return cookie value by name or NULL if does not present. */
1126 const char *http_find_cookie(const struct http_request *request,
1127         const char *name) {
1128     const struct http_header *header;
1129     size_t length;
1130     const char *value = NULL;
1131
1132     if (request == NULL || name == NULL) return NULL;
1133     length = strlen(name);
1134
1135     for (header = request->headers; header != NULL; header = header->next) {
1136         if (header->name != NULL && !strcasecmp(header->name, "Cookie") &&
1137                 header->value != NULL) {
1138             if (!strncmp(header->value, name, length) &&
1139                     header->value[length] == '=') {
1140                 /* Return last cookie with the name */
1141                 value = header->value + length + 1;
1142             }
1143         }
1144     }
1145     return value;
1146 }
1147
1148
1149 /* Return Host header value or NULL if does not present. Returned string is
1150  * statically allocated. */
1151 const char *http_find_host(const struct http_request *request) {
1152     const struct http_header *header;
1153     const char *value = NULL;
1154
1155     if (request == NULL) return NULL;
1156
1157     for (header = request->headers; header != NULL; header = header->next) {
1158         if (header->name != NULL && !strcmp(header->name, "Host")) {
1159                 value = header->value;
1160         }
1161     }
1162     return value;
1163 }
1164
1165
1166 /* Free a HTTP header and set it to NULL */
1167 void http_header_free(struct http_header **header) {
1168     if (header == NULL || *header == NULL) return;
1169     free((*header)->name);
1170     free((*header)->value);
1171     free(*header);
1172     *header = NULL;
1173 }
1174
1175
1176 /* Free linked list of HTTP headers and set it to NULL */
1177 void http_headers_free(struct http_header **headers) {
1178     struct http_header *header, *next;
1179
1180     if (headers == NULL || *headers == NULL) return;
1181
1182     for (header = *headers; header != NULL;) {
1183         next = header->next;
1184         http_header_free(&header);
1185         header = next;
1186     }
1187
1188     *headers = NULL;
1189 }
1190
1191 /* Free HTTP request and set it to NULL */
1192 void http_request_free(struct http_request **request) {
1193     if (request == NULL || *request == NULL) return;
1194     free((*request)->uri);
1195     http_headers_free(&((*request)->headers));
1196     free((*request)->body);
1197     free(*request);
1198     *request = NULL;
1199 }
1200
1201 /* Free HTTP response and set it to NULL */
1202 void http_response_free(struct http_response **response) {
1203     if (response == NULL || *response == NULL) return;
1204     free((*response)->reason);
1205     http_headers_free(&((*response)->headers));
1206     free((*response)->body);
1207     free(*response);
1208     *response = NULL;
1209 }