/* TCP/IP based server for HyperText TCPServer.c ** --------------------------------- ** ** History: ** 2 Oct 90 Written TBL. Include filenames for VM from RTB. */ /* Module parameters: ** ----------------- ** ** These may be undefined and redefined by syspec.h */ #define LISTEN_BACKLOG 2 /* Number of pending connect requests (TCP)*/ #define MAX_CHANNELS 20 /* Number of channels we will keep open */ #define BUFFER_SIZE 4096 /* Arbitrary size for efficiency */ #define WILDCARD '*' /* Wildcard used in addressing */ #define NETCLOSE close /* Routine to close a TCP-IP socket */ #define NETREAD read /* Routine to read from a TCP-IP socket */ #define NETWRITE write /* Routine to write to a TCP-IP socket */ #define FIRST_TCP_PORT 5000 /* When using dynamic allocation */ #define LAST_TCP_PORT 5999 #ifdef NeXT #define SELECT /* Handle >1 channel if we can. */ #include /* NeXT has all this packaged up */ #define ntohs(x) (x) #define htons(x) (x) #include #else #include /* VM doesn't have a built-in predefined token, so we cheat: */ #ifdef __STDIO__ #define VM #else #include /* For bzero etc - not NeXT or VM */ #endif #define SELECT /* Handle >1 channel if we can. */ #endif #ifndef VM #include #include #include #include /* Must be after netinet/in.h */ #include #include /* independent */ #include /* independent */ #define TOASCII(c) (c) #define FROMASCII(c) (c) #else /* VM */ #include #include #include #include #include #include #include /* independent */ extern char asciitoebcdic[], ebcdictoascii[]; #define TOASCII(c) (c=='\n' ? 10 : ebcdictoascii[c]) #define FROMASCII(c) (c== 10 ? '\n' : asciitoebcdic[c]) #include #define index(a,b) my_index(a,b) /* Why index() doesn't work I don't know */ #endif #include "utilities.h" /* Coding convention macros */ /* Default macros for manipulating masks for select() */ #ifndef FD_SET typedef unsigned int fd_set; #define FD_SET(fd,pmask) (*(pmask)) |= (1<<(fd)) #define FD_CLR(fd,pmask) (*(pmask)) &= ~(1<<(fd)) #define FD_ZERO(pmask) (*(pmask))=0 #define FD_ISSET(fd,pmask) (*(pmask) & (1<<(fd))) #endif /* Module-Global Variables ** ----------------------- */ PRIVATE enum role_enum {master, slave, transient, passive} role; PRIVATE struct sockaddr_in soc_address; /* See netinet/in.h */ PRIVATE int soc_addrlen; PRIVATE int master_soc; /* inet socket number to listen on */ PRIVATE int com_soc; /* inet socket number to read on */ PRIVATE fd_set open_sockets; /* Mask of channels which are active */ PRIVATE int num_sockets; /* Number of sockets to scan */ PRIVATE BOOLEAN dynamic_allocation; /* Search for port? */ PRIVATE char buffer[BUFFER_SIZE]; /* Find character within string ** ** See the ANSI definition of index() */ #ifdef VM char * my_index(char *s, char c) { char *p; for(p=s; *p && (*p!=c); p++) /*scan */ ; return *p ? p : 0; } #endif /* Read a file ** ----------- ** ** The function reads a file from the given file POINTER ** into the given file DESCRIPTOR! ** ** On exit, ** returns 0 for end of file, <0 for error. */ PRIVATE int read_file(int dest, FILE * source) { unsigned char * status; for(;;) { status = fgets(buffer, BUFFER_SIZE, source); if (!status) return -1; (void) write(dest, buffer, status); } } /* Strip white space off a string ** ** On exit, ** Return value points to first non-white character, or to 0 if none. ** All trailing white space is overwritten with zero. */ PRIVATE char * strip(char * s) { #define SPACE(c) ((c==' ')||(c=='\t')||(c=='\n')) char * p=s; for(p=s;*p;p++); /* Find end of string */ for(p--;p>=s;p--) { if(SPACE(*p)) *p=0; /* Zap trailing blanks */ else break; } while(SPACE(*s))s++; /* Strip leading blanks */ return s; } /* Send a string down a socket ** --------------------------- ** ** The trailing zero is not sent. ** There is a maximum string length. */ PRIVATE int write_ascii(int soc, char * s) { char * p; char ascii[255]; char *q = ascii; for (p=s; *p; p++) { *q++ = TOASCII(*p); } return write(soc, ascii, p-s); } /* Handle one message ** ------------------ ** ** On entry, ** soc A file descriptor for input and output. ** On exit, ** returns >0 Channel is still open. ** 0 End of file was found, please close file ** <0 Error found, please close file. */ int handle(int soc) { #define COMMAND_SIZE 255 #define MAX_LINES 10000 /* Maximum number of lines returned */ char command[COMMAND_SIZE+1]; int status; char * arg; /* Pointer to the argument string */ char * filename; /* Pointer to filename or group list*/ char * keywords; /* pointer to keywords */ char system_command[COMMAND_SIZE+1]; int lines, i; int fd; /* File descriptor number */ for (;;) { status = read(soc, command, COMMAND_SIZE); if (status<=0) { if (TRACE) printf("read returned %i, errno=%i\n", status, errno); return status; /* Return and close file */ } command[status]=0; /* terminate the string */ #ifdef VM { char * p; for (p=command; *p; p++) { *p = FROMASCII(*p); if (*p == '\n') *p = ' '; } } #endif if (TRACE) printf("read string is `%s'\n", command); arg=index(command,' '); if (arg) { *arg++ = 0; /* Terminate command & move on */ arg = strip(arg); /* Strip leading & trailing space */ if (0==strcmp("GET", command)) { /* Get a file */ /* Remove host and any punctuation. (Could use HTParse to remove access too @) */ filename = arg; if (arg[0]=='/') { if (arg[1]=='/') { filename = index(arg+2, '/'); /* Skip //host/ */ if (!filename) filename=arg+strlen(arg); } else { filename = arg+1; /* Assume root: skip slash */ } } if (*filename) { /* (else return test message) */ keywords=index(filename, '?'); if (keywords) *keywords++=0; /* Split into two */ #ifdef VM /* Formats supported by FIND are: ** ** /FIND Help for find general index ** /FIND/ (same) ** /FIND/? (same) ** /FIND/group.disk.ft.fn Get a document from a disk ** /FIND/grouplist? Help for group index ** /FIND/grouplist?keylist Search a set of disks for keywords ** where grouplist = group+group+group.. or void ** keylist = key+key+key... (not void) */ if((0==strncmp(filename,"FIND",4)) && ((filename[4]==0) || (filename[4]=='/') || (filename[4]='?'))) { filename=filename+4; if (*filename=='/') filename++; /* Skip first slash */ if (!*filename) { /* If no data at all, */ if (!keywords) keywords = filename; /* Respond as if just "?" given */ } if (keywords) { char *p; while((p=index(filename,'+'))!=0) *p=' ';/* Remove +s */ while((p=index(keywords,'+'))!=0) *p=' ';/* Remove +s */ if (!*keywords) { /* If no keywords */ write_ascii(soc, "Keyword Index\n"); if (*filename) { write_ascii(soc, "This index covers groups: `"); write_ascii(soc, filename); } else { write_ascii(soc, "This is the general CERN public document index"); } write_ascii(soc, ".

Use a keyword search to get documents, help files, etc.

\n"); return 0; } strcpy(system_command,"EXEC NICFIND1 "); strcat(system_command, keywords); if (*filename) { strcat(system_command, " ( "); strcat(system_command, filename); } } else { strcpy(system_command,"EXEC NICFOUN1 "); strcat(system_command, filename); } lines = system(system_command); if (TRACE) printf("Command `%s' returned %i lines.\n", system_command, lines); if (lines<=0) { write_ascii(soc, "\nSorry, the FIND server could not execute\n `"); write_ascii(soc, system_command); write_ascii(soc, "'\n\n"); return 0; } /* Copy the file across: */ for(;lines; lines--){ /* Speed necessary here */ char *p; fgets(buffer, BUFFER_SIZE, stdin); /* if (strcmp(buffer,"")==0) break; */ for(p=buffer; *p; p++) *p = TOASCII(*p); write(soc, buffer, p-buffer); } return 0; } /* if FIND */ #else fd = open(arg, O_RDONLY, 0 ); /* un*x open @@ */ if (fd<0) return fd; status = read_file(soc, fd); close(fd); return 0; #endif } } } write_ascii(soc, "

Small network access test v1.01

\n"); write_ascii(soc, "\n\nThe (unrecognised) command used was `"); write_ascii(soc, command); write_ascii(soc, "'.\n\n"); if (TRACE) printf("Return test string written back'\n"); return 0; /* End of file - please close socket */ } /* for */ } /* handle */ /*_____________________________________________________________________________________ */ /* Encode INET status (as in sys/errno.h) inet_status() ** ------------------ ** ** On entry, ** where gives a description of what caused the error ** global errno gives the error number in the unix way. ** ** On return, ** returns a negative status in the unix way. */ #ifdef vms extern int uerrno; /* Deposit of error info (as perr errno.h) */ extern int vmserrno; /* Deposit of VMS error info */ extern volatile noshare int errno; /* noshare to avoid PSECT conflict */ #else #ifndef errno extern int errno; #endif #endif PRIVATE int inet_status(where) char *where; { CTRACE(tfp, "TCP: Error %d in `errno' after call to %s() failed.\n", errno, where); #ifdef vms CTRACE(tfp, " Unix error number (uerrno) = %ld dec\n", uerrno); CTRACE(tfp, " VMS error (vmserrno) = %lx hex\n", vmserrno); #endif return -errno; } /* Parse a cardinal value parse_cardinal() ** ---------------------- ** ** On entry, ** *pp points to first character to be interpreted, terminated by ** non 0:9 character. ** *pstatus points to status already valid ** maxvalue gives the largest allowable value. ** ** On exit, ** *pp points to first unread character ** *pstatus points to status updated iff bad */ PRIVATE unsigned int parse_cardinal(pstatus, pp, max_value) int *pstatus; char **pp; unsigned int max_value; { int n; if ( (**pp<'0') || (**pp>'9')) { /* Null string is error */ *pstatus = -3; /* No number where one expeceted */ return 0; } n=0; while ((**pp>='0') && (**pp<='9')) n = n*10 + *((*pp)++) - '0'; if (n>max_value) { *pstatus = -4; /* Cardinal outside range */ return 0; } return n; } /* Bind to a TCP port ** ------------------ ** ** On entry, ** tsap is a string explaining where to take data from. ** "" means data is taken from stdin. ** "*:1729" means "listen to anyone on port 1729" ** ** On exit, ** returns Negative value if error. */ int do_bind(const char * tsap) { FD_ZERO(&open_sockets); /* Clear our record of open sockets */ num_sockets = 0; /* Deal with PASSIVE socket: ** ** A passive TSAP is one which has been created by the inet daemon. ** It is indicated by a void TSAP name. In this case, the inet ** daemon has started this process and given it, as stdin, the connection ** which it is to use. */ if (*tsap == 0) { /* void tsap => passive */ dynamic_allocation = FALSE; /* not dynamically allocated */ role = passive; /* Passive: started by daemon */ #ifdef vms { unsigned short channel; /* VMS I/O channel */ struct string_descriptor { /* This is NOT a proper descriptor*/ int size; /* but it will work. */ char *ptr; /* Should be word,byte,byte,long */ } sys_input = {10, "SYS$INPUT:"}; int status; /* Returned status of assign */ extern int sys$assign(); status = sys$assign(&sys_input, &channel, 0, 0); com_soc = channel; /* The channel is stdin */ CTRACE(tfp, "IP: Opened PASSIVE socket %d\n", channel); return -BAD(status); } #else com_soc = 0; /* The channel is stdin */ CTRACE(tfp, "IP: PASSIVE socket 0 assumed from inet daemon\n"); return 0; /* Good */ #endif /* Parse the name (if not PASSIVE) */ } else { /* Non-void TSAP */ char *p; /* pointer to string */ char *q; struct hostent *phost; /* Pointer to host - See netdb.h */ char buffer[256]; /* One we can play with */ register struct sockaddr_in* sin = &soc_address; strcpy(buffer, tsap); p = buffer; /* Set up defaults: */ sin->sin_family = AF_INET; /* Family = internet, host order */ sin->sin_port = 0; /* Default: new port, */ dynamic_allocation = TRUE; /* dynamically allocated */ role = passive; /* by default */ /* Check for special characters: */ if (*p == WILDCARD) { /* Any node */ role = master; p++; } /* Strip off trailing port number if any: */ for(q=p; *q; q++) if (*q==':') { int status; *q++ = 0; /* Terminate node string */ sin->sin_port = htons((unsigned short)parse_cardinal( &status, &q, (unsigned int)65535)); if (status<0) return status; if (*q) return -2; /* Junk follows port number */ dynamic_allocation = FALSE; break; /* Exit for loop before we skip the zero */ } /*if*/ /* Get node name: */ if (*p == 0) { sin->sin_addr.s_addr = INADDR_ANY; /* Default: any address */ } else if (*p>='0' && *p<='9') { /* Numeric node address: */ sin->sin_addr.s_addr = inet_addr(p); /* See arpa/inet.h */ } else { /* Alphanumeric node name: */ phost=gethostbyname(p); /* See netdb.h */ if (!phost) { CTRACE(tfp, "IP: Can't find internet node name `%s'.\n",p); return inet_status("gethostbyname"); /* Fail? */ } memcpy(&sin->sin_addr, phost->h_addr, phost->h_length); } CTRACE(tfp, "TCP: Parsed address as port %4x, inet %d.%d.%d.%d\n", (unsigned int)ntohs(sin->sin_port), (int)*((unsigned char *)(&sin->sin_addr)+0), (int)*((unsigned char *)(&sin->sin_addr)+1), (int)*((unsigned char *)(&sin->sin_addr)+2), (int)*((unsigned char *)(&sin->sin_addr)+3)); } /* scope of p */ /* Master socket for server: */ if (role == master) { /* Create internet socket */ master_soc = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (master_soc<0) return inet_status("socket"); CTRACE(tfp, "IP: Opened socket number %d\n", master_soc); /* If the port number was not specified, then we search for a free one. */ if (dynamic_allocation) { unsigned short try; for (try=FIRST_TCP_PORT; try<=LAST_TCP_PORT; try++) { soc_address.sin_port = htons(try); if (bind(master_soc, (struct sockaddr*)&soc_address, /* Cast to generic sockaddr */ sizeof(soc_address)) == 0) break; if (try == LAST_TCP_PORT) return inet_status("bind"); } CTRACE(tfp, "IP: Bound to port %u.\n", ntohs(soc_address.sin_port)); } else { /* Port was specified */ if (bind(master_soc, (struct sockaddr*)&soc_address, /* Case to generic address */ sizeof(soc_address))<0) return inet_status("bind"); } if (listen(master_soc, LISTEN_BACKLOG)<0) return inet_status("listen"); CTRACE(tfp, "TCP: Master socket(), bind() and listen() all OK\n"); FD_SET(master_soc, &open_sockets); if ((master_soc+1) > num_sockets) num_sockets=master_soc+1; return master_soc; } /* if master */ return -1; /* unimplemented role */ } /* do_bind */ /* Handle incomming messages do_action() ** ------------------------- ** ** On entry: ** ** timeout -1 for infinite, 0 for poll, else in units of 10ms ** ** On exit, ** returns The status of the operation, <0 if failed. ** */ #ifdef __STDC__ PRIVATE int do_action(void) #else PRIVATE int do_action() #endif { int tcp_status; /* <0 if error, in general */ int timeout = -1; /* No timeout required but code exists */ for(;;) { /* If it's a master socket, then find a slave: */ if (role == master) { #ifdef SELECT fd_set read_chans; fd_set write_chans; fd_set except_chans; int nfound; /* Number of ready channels */ struct timeval max_wait; /* timeout in form for select() */ FD_ZERO(&write_chans); /* Clear the write mask */ FD_ZERO(&except_chans); /* Clear the exception mask */ /* If timeout is required, the timeout structure is set up. Otherwise ** (timeout<0) a zero is passed instead of a pointer to the struct timeval. */ if (timeout>=0) { max_wait.tv_sec = timeout/100; max_wait.tv_usec = (timeout%100)*10000; } for (com_soc=-1; com_soc<0;) { /* Loop while connections keep coming */ /* The read mask expresses interest in the master channel for incomming ** connections) or any slave channel (for incomming messages). */ /* Wait for incoming connection or message */ read_chans = open_sockets; /* Read on all active channels */ if (TRACE) printf( "TcpAccess: Waiting for connection or message. (Mask=%x hex, max=%x hex).\n", *(int *)(&read_chans), num_sockets); nfound=select(num_sockets, &read_chans, &write_chans, &except_chans, timeout >= 0 ? &max_wait : 0); if (nfound<0) return inet_status("accept"); if (nfound==0) return 0; /* Timeout */ /* If an incomming connection has arrived, accept the new socket: */ if (FD_ISSET(master_soc, &read_chans)) { CTRACE(tfp, "TCP: New incomming connection:\n"); tcp_status = accept(master_soc, (struct sockaddr *)&soc_address, &soc_addrlen); if (tcp_status<0) return inet_status("accept"); CTRACE(tfp, "TCP: Accepted new socket %d\n", tcp_status); FD_SET(tcp_status, &open_sockets); if ((tcp_status+1) > num_sockets) num_sockets=tcp_status+1; nfound--; } /* end if new connection */ /* If a message has arrived on one of the channels, take that channel: */ if(nfound) { int i; for(i=0;;i++) if(FD_ISSET(i, &read_chans)) { if (TRACE) printf("Got new socket %i\n", i); com_soc = i; /* Got one! */ break; } break; /* Found input socket com_soc */ } /* if message waiting */ } /* loop on event */ #else /* SELECT not supported */ if (com_soc<0) { /* No slaves: must accept */ CTRACE(tfp, "TCP: Waiting for incomming connection...\n"); tcp_status = accept(master_soc, &rsoc->mdp.soc_tcp.soc_address, &rsoc->mdp.soc_tcp.soc_addrlen); if (tcp_status<0) return inet_status("accept"); com_soc = tcp_status; /* socket number */ CTRACE(tfp, "TCP: Accepted socket %d\n", tcp_status); } /* end if no slaves */ #endif } /* end if master */ /* com_soc is now valid for read */ /* Read the message now on whatever channel there is: */ CTRACE(tfp,"TCP: Reading socket %d\n", com_soc); tcp_status=handle(com_soc); if(tcp_status<=0) { /* EOF or error */ if (tcp_status<0) { /* error */ CTRACE(tfp, "TCP: Error %i handling incomming message (errno=%i).\n", tcp_status, errno); /* DONT return inet_status("netread"); error */ } else { CTRACE(tfp, "TCP: Socket %d disconnected by peer\n", com_soc); } if (role==master) { NETCLOSE(com_soc); FD_CLR(com_soc, &open_sockets); } else #ifdef VM return -69; ; #else return -ECONNRESET; #endif } /* end if handler got EOF or error */ }; /* for loop */ /*NOTREACHED*/ } /* end do_action */ /* Main program ** ------------ */ int main(int arc, char*argv[]) { int status; status = do_bind("*:2784"); if (status<0) { printf("Bad setup.\n"); exit(status); } status = do_action(); if (status<0) { printf("Error in server loop.\n"); exit(status); } exit(0); return 0; /* For gcc */ }