server.h Source File

00001 /*
00002  * FER - LSS - PPMPS
00003  * Fakultet elektrotehnike i računarstva (http://www.fer.hr/)
00004  * Unska 3, 10000 Zagreb, Hrvatska
00005  * 
00006  * (c) 2001 FER, Zagreb. Sva prava pridržana.
00007  * (c) 2001 LSS. Sva prava pridržana.
00008  */
00009 
00017 
00018 
00019 
00020 #ifndef __SERVER
00021 #define __SERVER
00022 
00023 
00024 
00025 #include <stdio.h>
00026 #include <stdlib.h>
00027 #include <errno.h>
00028 #include <string.h>
00029 #include <limits.h>
00030 #include <sys/types.h>
00031 #include <sys/wait.h>
00032 #include <sys/socket.h>
00033 #include <netinet/in.h>
00034 #include <arpa/inet.h>
00035 #include <netdb.h>
00036 #include <signal.h>
00037 #include <unistd.h>
00038 #include <ctype.h>
00039 #include <crypt.h>
00040 
00041 /* version */
00042 #ifndef VERSION
00043 #define VERSION "0.2.3"
00044 #endif
00045 
00046 #ifndef TRUE
00047 #define TRUE (1==1)
00048 #define FALSE (1!=1)
00049 #endif
00050 
00051 #define PORT 7777 /* the default port for connections */
00052 #define BACKLOG 10 /* how many pending connections queue will hold */
00053 #define ROOT_UID 0 /* root UID number */
00054 #define MAX_LOGIN 3 /* maximum number of login attempts */
00055 #define LOGIN_SLEEP_TIME 15 /* time in seconds between two login attempts */
00056 
00057 #define DEFAULT_CHANNEL 1 /* the default channel */
00058 #define DEFAULT_RESOLUTION 'M' /* the default resolution */
00059 #define DEFAULT_NO_SAMPLES 25 /* the default number of samples */
00060 
00061 #define MIN_CHANNEL 1 /* first channel */
00062 #define MAX_CHANNEL 8 /* last channel */
00063 #define DATA_STREAM -1 /* negative number of samples indicates stream */
00064 
00065 #define BUFFER_SIZE 256
00066 #define MAX_LENGTH 256 /* maximum username and password length*/
00067 
00068 #define DELIMITERS " \t\n\x0A\x0D" /* command delimiters */
00069 
00070 /* values of authorisation flag */
00071 #define NOAUTH 0
00072 #define AUTH 1
00073 #define AUTHORISED (1+2)
00074 #define NOTAUTHORISED (1+4)
00075 #define AUTHNOTPROCESSED 8
00076 
00077 /* values of test mode flag */
00078 #define MODENOTPROCESSED (1+2)
00079 #define MODEPROCESSED (1+4)
00080 
00081 /* some defines for data acquisition */
00082 #define ACQUIRE_SUCCESS 0
00083 #define ACQUIRE_FAILURE 1
00084 #define HIGH_RESOLUTION_STEP 1
00085 #define MEDIUM_RESOLUTION_STEP 2
00086 #define LOW_RESOLUTION_STEP 5
00087 #define STREAM_CHUNK 128
00088 
00099 typedef
00100 enum _command_no_t
00101 {
00102   CN_ERROR = -2,
00103   CN_NO_COMMAND = -1,
00104   CN_USER = 0,
00105   CN_PASS,
00106   CN_SET,
00107   CN_GET,
00108   CN_RESOLUTION,
00109   CN_START,
00110   CN_STOP,
00111   CN_HELP,
00112   CN_BYE,
00113   CN_EXIT,
00114   CN_QUIT,
00115   MAX_CN_NO
00116 } command_no_t;
00117 
00118 /* command strings */
00119 static const char *command[] =
00120 {
00121   "USER",
00122   "PASS",
00123   "SET",
00124   "GET",
00125   "RESOLUTION",
00126   "START",
00127   "STOP",
00128   "HELP",
00129   "BYE",
00130   "EXIT",
00131   "QUIT"
00132 };
00133 
00134 /* help messages */
00135 static const char *help_message[] =
00136 {
00137   "214 HELP USER OK\n"
00138   "214 USER <username>\n"
00139   "214 Sets user name.\n",
00140 
00141   "214 HELP PASS OK\n"
00142   "214 PASS <password>\n"
00143   "214 Sets password for given username.\n"
00144   "214 Username must be specified before.\n",
00145 
00146   "214 HELP SET OK\n"
00147   "214 SET <channel number>\n"
00148   "214 Sets channel. Allowed channel numbers\n"
00149   "214 are between zero and eight.\n"
00150   "214 Default channel is 1.\n",
00151 
00152   "214 HELP GET OK\n"
00153   "214 GET <number of samples>\n"
00154   "214 Specifes number of samples to send after START command\n"
00155   "214 is given. Number of samples must be either positive\n"
00156   "214 integer or word STREAM. For STREAM samples are sent\n"
00157   "214 continously until STOP is given.\n"
00158   "214 Default value is 25 samples.\n",
00159 
00160   "214 HELP RESOLUTION OK\n"
00161   "214 RESOLUTION <resolution>\n"
00162   "214 Sets resolution. Allowed values for resolution are:\n"
00163   "214  H, HIGH    - high resolution, 1 ms\n"
00164   "214  M, MEDIUM  - medium resolution, 100 ms\n"
00165   "214  L, LOW     - low resolution, 10 s\n"
00166   "214 Default value is M.\n",
00167 
00168   "214 HELP START OK\n"
00169   "214 START\n"
00170   "214 Sends data. See STOP and GET.\n",
00171 
00172   "214 HELP STOP OK\n"
00173   "214 STOP\n"
00174   "214 Stops data stream. See START and GET.\n",
00175 
00176   "214 HELP HELP OK\n"
00177   "214 HELP [ <command> ]\n"
00178   "214 Gives useful informations about commands.\n",
00179 
00180   "214 HELP BYE OK\n"
00181   "214 BYE\n"
00182   "214 Exit ADC-ZESOI server.\n",
00183 
00184   "214 HELP EXIT OK\n"
00185   "214 EXIT\n"
00186   "214 Exit ADC-ZESOI server.\n",
00187 
00188   "214 HELP QUIT OK\n"
00189   "214 QUIT\n"
00190   "214 Exit ADC-ZESOI server.\n",
00191 
00192   "214 HELP OK\n"
00193   "214 Commands are:\n"
00194   "214 USER   GET   START   HELP    QUIT\n"
00195   "214 PASS   SET   STOP    RESOLUTION  \n"
00196   "214 For more information use HELP <command>.\n"
00197 };
00198 
00199 #define GET_STREAM_ARGUMENT "STREAM"
00200 #define RESOLUTION_HIGH "HIGH"
00201 #define RESOLUTION_H "H"
00202 #define RESOLUTION_MEDIUM "MEDIUM"
00203 #define RESOLUTION_M "M"
00204 #define RESOLUTION_LOW "LOW"
00205 #define RESOLUTION_L "L"
00206 #define RESOLUTION_HC 'H'
00207 #define RESOLUTION_MC 'M'
00208 #define RESOLUTION_LC 'L'
00209 
00210 
00220 typedef
00221 enum _error_code_t
00222 {
00223   EC_PARSE_FAILURE = -2,
00224   EC_NO_ERROR = -1,
00225 
00226   EC_UNKNOWN_COMMAND = 0,
00227 
00228   EC_USER_ERROR,
00229   EC_USER_UNKNOWN,
00230   EC_USER_OVERRUN,
00231   EC_USER_NO_NAME,
00232   EC_USER_NO_AUTHORISATION_REQUIRED,
00233 
00234   EC_PASS_ERROR,
00235   EC_PASS_INCORRECT,
00236   EC_PASS_EXPIRED,
00237   EC_PASS_NO_USER_NAME,
00238   EC_PASS_ALREADY_AUTHORISED,
00239   EC_PASS_OVERRUN,
00240   EC_PASS_NO_PASS,
00241   EC_PASS_NO_AUTHORISATION_REQUIRED,
00242   EC_PASS_DISCONNECTED,
00243   EC_PASS_PASSWORDLESS,
00244   EC_PASS_DENIED,
00245   EC_PASS_LOCKED,
00246 
00247   EC_SET_ERROR,
00248   EC_SET_INVALID,
00249   EC_SET_UNAVAILABE,
00250   EC_SET_UNAUTHORISED,
00251   EC_SET_NO_CHANNEL,
00252 
00253   EC_GET_ERROR,
00254   EC_GET_INVALID_NO_OF_SAMPLES,
00255   EC_GET_UNAUTHORISED,
00256   EC_GET_NO_ARGUMENT,
00257 
00258   EC_RESOLUTION_ERROR,
00259   EC_RESOLUTION_INVALID,
00260   EC_RESOLUTION_UNAUTHORISED,
00261   EC_RESOLUTION_NO_ARGUMENT,
00262 
00263   EC_START_ERROR,
00264   EC_START_UNAUTHORISED,
00265 
00266   EC_STOP_ERROR,
00267   EC_STOP_NO_STREAM,
00268   EC_STOP_UNAUTHORISED,
00269 
00270   EC_HELP_INVALID_COMMAND
00271 } error_code_t;
00272 
00273 /* error messages */
00274 static const char *error_message[] =
00275 {
00276   "500 ERROR: Unknown command. See HELP.\n",
00277 
00278   "501 USER ERROR\n",
00279   "502 USER ERROR: Unknown user.\n",
00280   "503 USER ERROR: Username to long.\n",
00281   "504 USER ERROR: Must supply user name.\n",
00282   "505 USER ERROR: Authorisation not required.\n",
00283 
00284   "510 PASS ERROR\n",
00285   "511 PASS ERROR: Incorrect password.\n",
00286   "512 PASS ERROR: Account expired.\n",
00287   "513 PASS ERROR: No user name.\n",
00288   "514 PASS ERROR: Already authorised.\n",
00289   "515 PASS ERROR: Password to long.\n",
00290   "516 PASS ERROR: Must supply password.\n",
00291   "517 PASS ERROR: Authorisation not required.\n",
00292   "518 PASS ERROR: Maximum login attempts number reached.\n",
00293   "519 PASS ERROR: Paswordless accounts are disabled.\n",
00294   "520 PASS ERROR: Access for %s denied.\n",
00295   "521 PASS ERROR: Account locked.\n",
00296 
00297   "530 SET ERROR\n",
00298   "531 SET ERROR: Invalid channel number.\n",
00299   "532 SET ERROR: Channel unavailabe.\n",
00300   "533 SET ERROR: Authorisation required for SET.\n",
00301   "534 SET ERROR: No channel number given.\n",
00302 
00303   "535 GET ERROR\n",
00304   "536 GET ERROR: Invalid number of samples.\n",
00305   "537 GET ERROR: Authorisation required for GET.\n",
00306   "538 GET ERROR: Must specify number of samples or stream.\n",
00307 
00308   "540 RESOLUTION ERROR\n",
00309   "541 RESOLUTION ERROR: Invalid resolution.\n",
00310   "542 RESOLUTION ERROR: Authorisation required for RESOLUTION.\n",
00311   "543 RESOLUTION ERROR: No resolution specified.\n",
00312 
00313   "550 START ERROR\n",
00314   "551 START ERROR: Authorisation required for START.\n",
00315 
00316   "555 STOP ERROR\n",
00317   "556 STOP ERROR: No stream.\n",
00318   "557 STOP ERROR: Authorisation required for STOP.\n",
00319 
00320   "599 HELP ERROR: Invalid command.\n"
00321   "214 Commands are:\n"
00322   "214 USER   GET   START   HELP    QUIT\n"
00323   "214 PASS   SET   STOP    RESOLUTION  \n"
00324   "214 For more information use HELP <command>.\n"
00325 };
00326 
00327 
00328 
00336 typedef
00337 enum _ok_message_no_t
00338 {
00339   MN_USER = 0,
00340 
00341   MN_PASS,
00342 
00343   MN_SET,
00344 
00345   MN_GET_STREAM,
00346   MN_GET_SAMPLES,
00347 
00348   MN_RESOLUTION,
00349 
00350   MN_START_STREAM,
00351   MN_START_SAMPLES,
00352   MN_START_TEST_SAMPLES,
00353   MN_START_TEST_STREAM,
00354   MN_START_RESOLUTION,
00355 
00356   MN_STOP,
00357 
00358   MN_TRANSFER_COMPLETED,
00359 
00360   MN_WELCOME,
00361   MN_GOODBYE
00362 } _ok_message_no_t;
00363 
00364 /* ok messages */
00365 static const char *ok_message[] =
00366 {
00367   "250 USER OK: Username set to %s.\n"
00368   "250 Use PASS to send password.\n",
00369 
00370   "250 PASS OK: Hello %s. No restrictions apply.\n",
00371 
00372   "250 SET OK: Channel set to %d.\n",
00373 
00374   "250 GET OK: Samples will be sent as data stream.\n",
00375   "250 GET OK: Number of samples set to %d.\n",
00376 
00377   "250 RESOLUTION OK: Resolution set to %c.\n",
00378 
00379   "251 START OK: Sending data stream.\n"
00380   "251 Use STOP to stop transmission.\n",
00381   "250 START OK: Sending %d samples.\n",
00382   "300 Test mode active: Sending %d random samples.\n",
00383   "300 Test mode active: Sending random data stream.\n",
00384   "333 Resoultion is %c.\n",
00385 
00386   "250 STOP OK: Stream stopped.\n",
00387 
00388   "333 Transfer completed.\n",
00389 
00390   "220 Welcome to ADC-ZESOI server v" VERSION " at %s.\n",
00391   "221 BYE OK ADC-ZESOI server v" VERSION " at %s signing off.\n"
00392 };
00393 
00394 
00395 
00404 typedef
00405 struct _command_t
00406 {
00407   command_no_t command_no;
00408   error_code_t error_code;
00409   command_no_t help_code;
00410   int no_of_samples;
00411   int channel;
00412   short int authorised;
00413   short int stream;
00414   short int exit;
00415   char resolution;
00416   char username[MAX_LENGTH+1];
00417   char password[MAX_LENGTH+1];
00418 }
00419 command_t;
00420 
00421 /* global variables */
00422 int global_fd;
00423 unsigned int global_max_login_no;
00424 short int global_null_ok;
00425 pid_t global_pid;
00426 pid_t global_stream_pid;
00427 
00428 /* global flag for test mode */
00429 #ifdef TEST_MODE
00430 short int global_test_mode = TRUE;
00431 #else
00432 short int global_test_mode = FALSE;
00433 #endif
00434 
00435 
00436 
00437 /* command loop functions */
00438 char * readcommand (int);
00439 command_t parsecommand (const char *, command_t);
00440 command_t executecommand (command_t, command_t, int);
00441 
00442 /* data acquisition */
00443 int acquireandsendsamples (int, int, int, char);
00444 
00445 /* signal handlers */
00446 void lostconnection (int);
00447 void stopstream (int);
00448 void cleanallchildren (int);
00449 
00450 
00451 
00452 #endif /* !__SERVER */
00453 
00454