轻量级支持CGI的web服务器

来源：互联网发布：linux进程调度代码编辑：程序博客网时间：2024/06/05 05:16

/* mattows.c  * msbethke 2006  * A quick'n'dirty HTTP server that can deliver HTML, GIF, JPEG,  * PNG and CSS, and executes CGI files ending in ".cgi"  *  * NEW: goes daemon on `-d' argument; default port is 28001  *   * TODO: support POST method (only GET and HEAD so far); proper commandline  * parsing  *  * $Id: mattows.c,v 1.8 2006/07/04 21:55:46 mb Exp mb $  */  #include <stdio.h> #include <stdlib.h> #include <string.h> #include <strings.h> #include <ctype.h> #include <stdarg.h> #include <unistd.h> #include <fcntl.h> #include <errno.h> #include <signal.h> #include <sys/types.h> #include <sys/socket.h> #include <sys/stat.h> #include <sys/wait.h> #include <arpa/inet.h> #include <netinet/in.h> #include <netdb.h> #include <dirent.h>  #define _STRINGIFY(x) #x  #define LOGFILENAME "mattows.log" #define PORT 28001 #define PORTSTR _STRINGIFY(PORT)  /* write an HTTP message (or any string) to a file descriptor */ #define HTTPMSG(fh,msg) fputs((msg),(fh))  /* Determine elements in an array */ #define NELEMS(x) (sizeof(x)/sizeof(*x))  /* some HTML stuff for dir listings */ #define DIR_DOCTYPE "<!DOCTYPE HTML PUBLIC /"-//W3C//DTD HTML 4.01//EN/" /"http://www.w3.org/TR/html4/strict.dtd/">/n" #define DIR_HEAD1 "<html>/n<head><title>" #define DIR_HEAD2 "</title></head>/n<body>/n<ul style="/" mce_style="/""list-style-type:none/">/n" #define DIR_FOOT  "</ul>/n</body>/n</html>" #define DIR_ENT1  "<li><a href="/" mce_href="/""" #define DIR_ENT2  "/">" #define DIR_ENT3  "</a></li>/n" #define DIR_DIRMARK "[DIR] "  typedef enum {false=0,true} bool; enum {ENVSIZE=20}; typedef struct MYENV {     int nenv;     char *ptrs[ENVSIZE]; } myenv;  typedef struct EXT2MIME {     const char *type;     const char* const ext[]; } ext2mime; typedef enum {M_INVALID=0, M_GET=1, M_HEAD=2} reqtype;  static const ext2mime ext_html = {"text/html",{"html","htm",NULL}}; static const ext2mime ext_gif  = {"image/gif",{"gif",NULL}}; static const ext2mime ext_png  = {"image/png",{"png",NULL}}; static const ext2mime ext_jpeg = {"image/jpeg",{"jpg","jpeg","jfif",NULL}}; static const ext2mime ext_css  = {"text/css",{"css",NULL}}; static const ext2mime* const extensions[] = {     &ext_html, &ext_gif, &ext_png, &ext_jpeg, &ext_css, NULL }; static const char* const cgiext[] = {"cgi","pl","sh"}; static const char MIME_GENERIC[] = "application/ocet-stream";  static char *method_strings[3]; static char *progname, *addrstr, *portstr = PORTSTR; static in_addr_t addr; static short port = PORT; static myenv cgienv = {     3,{         "SERVER_SOFTWARE=mattows",         "GATEWAY_INTERFACE=CGI/1.2",         "SERVER_PROTOCOL=HTTP/1.0"     } }; static bool daemonize = false;  /* HTTP codes */ const char HTTPV[] = "HTTP/1.0 "; const char M200[] = "200 OK/r/n"; const char E400[] = "400 Bad request/r/n"; const char E404[] = "404 Not found/r/n"; const char E403[] = "403 Forbidden/r/n"; const char E501[] = "501 Not implemented/r/n";  #ifdef REALLYTINY /* avoid use of printf */  /* program usage */ static void usage(void) {     fputs("Usage: ",stderr);     fputs(progname,stderr);     fputs("[-d] <ip> [port]/n",stderr);     exit(EXIT_FAILURE); }  static void mywarn(char *s, ...) { } static void myerror(int code, char *s, ...) {     fputs("ABEND/n",stderr);     exit(code); } #else /* program usage */ static void usage(void) {     fprintf(stderr,"Usage: %s [-d] [ip] <port>/n",progname);     exit(EXIT_FAILURE); }  /* print message in arglist */ static void vmywarn(char *s, va_list ap) {     fprintf(stderr,"%s [%d]: ",progname,(int)getpid());     vfprintf(stderr,s,ap); }  /* print message in varargs */ static void mywarn(char *s, ...) {     va_list ap;     va_start(ap,s);     vmywarn(s,ap);     va_end(ap); }  /* print message in varargs and exit with error code */ static void myerror(int code, char *s, ...) {     va_list ap;     va_start(ap,s);     vmywarn(s,ap);     va_end(ap);     exit(code); } #endif /* REALLYTINY */  /* get hostname for an IP4 address in network byte order */ static char *getmyhostname(in_addr_t addr) {     enum {AUXBUFSIZE=1024};     struct in_addr ad;     struct hostent he, *hp;     int err;     char *auxbuf;          ad.s_addr = addr;     /* auxbuf is unused anyway, so ignore ERANGE */     if(!(auxbuf=alloca(AUXBUFSIZE)) ||             /* this will probably break on Solaris */             gethostbyaddr_r((void*)&ad,sizeof(ad),AF_INET,                 &he,auxbuf,AUXBUFSIZE,&hp,&err) ||             !hp)         return "(no-hostname)";     return he.h_name; }  /* evaluate arguments to global vars  * TODO: this is getting big. might as well do it properly...  */ static void eval_args(int c, char *v[]) {     int n=1;      while(1) {         if(c <= n)             usage();         if('-' != v[n][0])             break;         switch(v[n][1]) {             case 'h' :                 usage();             case 'd' :                 daemonize = true;                 break;             default :                 myerror(EXIT_FAILURE,"unknown option %s/n",v[n]);         }         ++n;     }          addr = inet_addr(v[n]);     if(INADDR_NONE == addr) {         /* address parsing failed, assume it's a port */         addr = INADDR_ANY;         addrstr = getmyhostname(htonl(0x7f000001));     } else {         ++n;         addrstr = getmyhostname(addr);     }     if(c <= n)         return;     port = atoi(portstr = v[n]);     mywarn("ADDR: %s; PORT: %hd/n",addrstr,port);     if(!port)         usage(); }  static void send_ok_mime(FILE *to, const char *mimetype) {     HTTPMSG(to,M200);     HTTPMSG(to,"Content-Type: ");     HTTPMSG(to,mimetype);     HTTPMSG(to,"/r/n/r/n"); }  static int entrymode(char *path) {     struct stat st;      if(0 != stat(path,&st))         return 0;     return st.st_mode; }  /* send <dir> in primitive HTML to <to> */ static int send_dir(char *dir, FILE *to) {     int ret = EXIT_FAILURE;     DIR *dh = opendir(dir);     struct dirent *de;     if(NULL == dh) {         /* diretory failed to open */         HTTPMSG(to,E404);         return ret;     }     send_ok_mime(to,ext_html.type);     HTTPMSG(to,DIR_DOCTYPE DIR_HEAD1);     HTTPMSG(to,dir);     HTTPMSG(to,DIR_HEAD2);     errno = 0;     while(NULL != (de = readdir(dh))) {         int type;         char *name = de->d_name;         if(('.' == name[0]) && ('/0' == name[1]))             continue;         type = entrymode(name);         if(!(S_ISDIR(type) || S_ISREG(type)))             continue;    /* ignore stuff that isn't regular file or dir */         HTTPMSG(to,DIR_ENT1);         HTTPMSG(to,name);         if(S_ISDIR(type))             HTTPMSG(to,"/");         HTTPMSG(to,DIR_ENT2);         if(S_ISDIR(type))                 HTTPMSG(to,DIR_DIRMARK);         HTTPMSG(to,name);         HTTPMSG(to,DIR_ENT3);     }     HTTPMSG(to,DIR_FOOT);     if(errno)         mywarn("Could not send dir: %s/n",strerror(errno));     else         ret = EXIT_SUCCESS;     return ret; }  /* Read from file named <from>, write to FH <to> adding MIME header */ static int send_file(char *from, FILE *to, const char *mimetype) {     char buf[4096];     int writing=1, file, rdsize,ret = EXIT_FAILURE;          file = open(from,O_RDONLY);     /* check if file opened, 403 if not */     if(-1 != file) {         mywarn("Sending %s/n",from);         HTTPMSG(to,M200);         HTTPMSG(to,"Content-Type: ");         HTTPMSG(to,mimetype);         HTTPMSG(to,"/r/n/r/n");         while(writing) {             switch(rdsize = read(file,buf,sizeof(buf))) {                 case -1:                     mywarn("read error on %s: %s/n",from,strerror(errno));                     ret = EXIT_FAILURE;                     /* fallthru */                 case 0:                     writing = 0;                     break;                 default :                     fwrite(buf,1,rdsize,to);             }         }         close(file);     } else {         mywarn("error opening /"%s/": %s/n",from,strerror(errno));         HTTPMSG(to,E403);     }     return ret; }  /* enter a new string for a KEY=VALUE environment entry into  * the env array  */ static void addenv(myenv *env, char *key, char *val) {     char *s;     int keylen = strlen(key);     int vallen = strlen(val);     if((s = malloc(keylen + 1 + vallen + 1))) {         strcpy(s,key);         s[keylen] = '=';         strcpy(s+keylen+1,val);         env->ptrs[env->nenv++] = s;     } }  /* build an env array for CGIs */ static char **buildenv(myenv *env,         reqtype method,         char *scriptname,         char *query,         char *peer) {     addenv(env,"REQUEST_METHOD",method_strings[method]);     // addenv(env,"PATH_INFO","");     // addenv(env,"PATH_TRANSLATED","");     addenv(env,"SCRIPT_NAME",scriptname);     // addenv(env,"REMOTE_HOST","");     addenv(env,"REMOTE_ADDR",peer);     if(query)         addenv(env,"QUERY_STRING",query);     return env->ptrs; }  static reqtype check_reqtype(char *req) {     if(!strncmp("GET",req,3)) return M_GET;     if(!strncmp("HEAD",req,4)) return M_HEAD;     return M_INVALID; }  static void handle_cgi(char *prog, char *query, reqtype method,         FILE *out, struct  sockaddr_in *peer) {     char *args[2] = {0};     int pid;     int pipefds[2];     FILE *pipefh;     mywarn("Executing %s/n",prog);     args[0] = prog;     HTTPMSG(out,M200);     fflush(out);     buildenv(&cgienv,method,prog,query,inet_ntoa(peer->sin_addr));     switch(method) {         case M_HEAD :             if(0 != pipe(pipefds)) {                 myerror(EXIT_FAILURE,"pipe(): %s",strerror(errno));                 break;             }             switch(pid = fork()) {                 char buf[4096];                  case -1 :                     myerror(EXIT_FAILURE,                             "error forking CGI process: %s/n",strerror(errno));                     break;                 case 0 :                     dup2(pipefds[1],1);                     execve(prog,args,cgienv.ptrs);                     break; /* yeah right... */                 default :                     pipefh = fdopen(pipefds[0],"r");                     while(fgets(buf,sizeof(buf),pipefh)) {                         fputs(buf,out);                         if('/r' == buf[0] && '/n' == buf[1])                             break;                     }                     fclose(pipefh);             }             break;          case M_GET:         default:             dup2(fileno(out),1);             execve(prog,args,cgienv.ptrs);             break;     } }  static const char *find_mime_type(char *buf) {     const ext2mime *e2m;     int i,j;     for(i=0; (e2m=extensions[i]); ++i)         for(j=0; e2m->ext[j]; ++j)             if(!strcasecmp(buf,e2m->ext[j]))                 return e2m->type;     return MIME_GENERIC; }  /* read HTTP request and respond */ static int handle_connection(int fd, struct sockaddr_in *peer) {     char buf[4096];     char *uri, *doc, *t, *query=NULL;     struct stat st;     int ret = EXIT_FAILURE;     reqtype method;     FILE *fh = fdopen(fd,"r+");      if(!fh) return ret;        /* very bad, don't bother with messages */           /* check for valid request: fgets() ok && 5<=req<=sizeof(buf) */     if(fgets(buf,sizeof(buf),fh) && strlen(buf) >= 5 &&             !(strlen(buf) >= sizeof(buf)-2 && '/0' != buf[sizeof(buf)-1])) {          /* ignore rest of request for now */         do {             char dummy[4096];             while(fgets(dummy,sizeof(dummy),fh)) {                 if('/r' == dummy[0] && '/n' == dummy[1])                     break;             }         } while(0);          /* write HTTP version for reply */         fputs(HTTPV,fh);              switch(method = check_reqtype(buf)) {             case M_GET :                 uri = buf + 4;                 break;             case M_HEAD:                 uri = buf + 5;                 break;             default :                 HTTPMSG(fh,E501);                 goto leave;         }         doc = uri;         /* skip leading '/' */         *doc == '/' && ++doc;         /* zero-terminate document name, get optional query string */         for(t=doc; *t && !isspace(*t); ++t) {             if('?' == *t) {                 query = t+1;                 break;             }         }         *t = '/0';         /* if a query part is present, it still needs to be terminated */         if(query) {             for(++t; *t && !isspace(*t); ++t) /* just loop */ ;             *t = '/0';         }         /* top dir must be "." */         if(!strlen(doc))             doc = ".";         /* check if requested file/script exists, 404 if not */         if(0 == stat(doc,&st)) {             char const *mimetype = MIME_GENERIC;             /* check for directory */             if(S_ISDIR(st.st_mode)) {                 ret = send_dir(doc,fh);                 goto leave;             }             /* find file extension and infer MIME type */             char *ext = strrchr(doc,'.');             if(ext) {                 int i;                 /* check for CGI script */                 ++ext;                 for(i=0; i<NELEMS(cgiext); ++i) {                     if(!strcasecmp(cgiext[i],ext)) {                         handle_cgi(doc,query,method,fh,peer);                         return EXIT_SUCCESS;        /* we only get back here for HEAD! */                     }                 }                 /* delivery only */                 mimetype = find_mime_type(ext);             }             /* can only use GET on plain files */             if(M_GET == method) ret = send_file(doc,fh,mimetype);             else HTTPMSG(fh,E400);         } else {             mywarn("File not found: '%s'/n",doc);             HTTPMSG(fh,E404);         }     } else {         fputs(HTTPV,fh);         HTTPMSG(fh,E400);     } leave:     fclose(fh);     return ret; }  /* clean up dead children */ static void child_reaper(int sig) {     int status, pid;      while(0 < (pid = waitpid(-1,&status,WNOHANG)))         mywarn("Child process %d exited with status %d/n",pid,status); }  /* do some work */ int main(int argc, char *argv[]) {     int sock,as,sockopt=1;     struct sockaddr_in bindaddr, peer;     struct sigaction sa = {         .sa_handler = &child_reaper,         .sa_flags = SA_NOCLDSTOP     };      /* basename($0) */     progname = argv[0] + strlen(argv[0]);     while((progname > argv[0]) && (progname[-1] != '/'))         --progname;     eval_args(argc,argv);     port = htons(port);      /* set up method-to-string translation table */     method_strings[M_INVALID]    = "INVALID";     method_strings[M_GET]        = "GET";     method_strings[M_HEAD]        = "HEAD";          sock = socket(AF_INET,SOCK_STREAM,0);     if(-1 == sock)         myerror(EXIT_FAILURE,"socket: %s/n",strerror(errno));         setsockopt(sock,getprotobyname("tcp")->p_proto,             SO_REUSEADDR,&sockopt,sizeof(sockopt));     bindaddr.sin_family = PF_INET;     bindaddr.sin_port = port;     bindaddr.sin_addr.s_addr = addr;     if(-1 == bind(sock,(struct sockaddr*)&bindaddr,sizeof(bindaddr)))         myerror(EXIT_FAILURE,"bind: %s/n",strerror(errno));          if(daemonize) {         pid_t daemon = fork();         if(-1 == daemon)             myerror(EXIT_FAILURE,"cannot daemonize: %s/n",strerror(errno));         /* forked successfully, exit parent */         if(daemon)             exit(EXIT_SUCCESS);         /* child continues */         umask(0);         stderr = freopen(LOGFILENAME,"a+",stderr);         setlinebuf(stderr);         if(0 == stderr)             myerror(EXIT_FAILURE,"cannot open log /"%s/": %s/n",                     LOGFILENAME,strerror(errno));         close(STDIN_FILENO);         close(STDOUT_FILENO);         setsid(); /* should always succeed in child */     }          listen(sock,10);      sigaction(SIGCHLD,&sa,NULL);      /* fill constant elements in CGI's env array already */     addenv(&cgienv,"SERVER_NAME",addrstr);     addenv(&cgienv,"SERVER_PORT",portstr);          while(1) {         int pid;         socklen_t peerlen=sizeof(peer);                  mywarn("Waiting for connections on port %d/n",ntohs(port));         as = accept(sock,(struct sockaddr*)&peer,&peerlen);         if(-1 == as) {             if(EINTR != errno)                 mywarn("accept: %s/n",strerror(errno));             continue;         }         switch(pid = fork()) {             case -1 :                 mywarn("error forking connection handler: %s/n",strerror(errno));                 break;             case 0 :                 close(sock);                 mywarn("Accepted connection from %s:%d/n",                         inet_ntoa(peer.sin_addr),ntohs(peer.sin_port));                 exit(handle_connection(as,&peer));             default :                 close(as);         }     }     close(sock);     return EXIT_SUCCESS; }  /* vi: set ts=3 sw=3 noet cindent: */

/* * cheetah.c * * Copyright (C) 2003 Luke Reeves (luke@neuro-tech.net) * http://www.neuro-tech.net/ * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2, or (at your option) any * later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * */ #include "config.h" #ifdef HAVE_SYS_SENDFILE_H #include <sys/sendfile.h> #endif #include <sys/wait.h> #include <string.h> #include <stdio.h> #include <time.h> #include <stdlib.h> #include <unistd.h> #include <sys/mman.h> #include <dirent.h> #include <signal.h> #include <sys/stat.h> #include <fcntl.h> #include <sys/socket.h> #include <time.h> #include <netdb.h> #include <arpa/inet.h> #include <netinet/in.h> #include <errno.h> #define METHOD_GET 0 #define METHOD_HEAD 1 #define METHOD_UNSUPPORTED -1 #define SERVER_NAME "Cheetah" /* Globals */ char * default_type = "text/plain"; int generate_index = 0; int verbose = 0; int background = 0; int sockfd = -1; int print_headers = 0; /* Print headers to screen. */ int loglevel = 0; int links = 0; /* Linked list of files being shared. This is much slower than simply opening * files off disk (and I'm too lazy to write a hashtable), but this is a much * more safe and secure way. */ typedef struct FSTRUCT { char * filename; char * fullpath; void * next; /* Only for internal files */ char * content; int content_length; char * content_type; char * last_modified; } servable; servable * files = NULL; servable * index_page = NULL; static void help() { printf("Usage: cheetah [OPTIONS] [DIRECTORY]/n"); printf("Serves up the files listed in the specified directory using HTTP./n"); printf("Note that the list of files is scanned on startup only - to rescan the files/n"); printf("for additions, you must restart cheetah./n/n"); printf("-d, --default-type default mime-type if file isn't found in the database,/n"); printf(" defaults to text/plain/n"); printf("-b background mode (disables console output, and allows/n"); printf(" multiple requests to be served simultaneously)/n"); printf("-g generate indices for the root directory when no index.html/n"); printf(" is found/n"); printf(" --headers print out all client request headers/n"); printf("-l, --log log (in combined log format) all requests to standard/n"); printf(" output/n"); printf("-p, --port port to listen for requests on, defaults to 8000/n"); printf("-s follow symbolic links/n"); printf("-v verbose output/n"); printf("-V print version and exit/n"); printf("-h, --help display this message and exit/n"); printf("/n"); printf("Please see http://www.neuro-tech.net/cheetah for updates and bug reporting./n"); } char * msg404 = "<html><head><title>404 Not Found</title></head><body>/ <h1>404 Not Found</h1><h2>The document requested was not found.</h2></body></html>/n"; /* SIGHUP handler */ static void sigcatch(int signal); /* Prototypes */ static void handle_request(int fd, struct sockaddr_in * remote); static servable * gen_index(); static void handle_connection(int fd, struct sockaddr_in * remote); static int get_method(char * req); static servable * match_request(char * req); static int safesend(int fd, char * out); static char * get_mimetype(char * file); static void crit(char * message); static void warn(char * message); static void * smalloc(size_t size); int main(int argc, char *argv[]) { int port = 8000; struct sockaddr_in my_addr; struct sockaddr_in remote_addr; int sin_size; int flength; char * fullpath = NULL; char * dir = NULL; DIR * dirpnt; struct dirent * curdir = NULL; struct stat curstat; servable * curfile = NULL; servable * lastfile = NULL; int newfd; int i, fr, rv; /* Parse options */ if(argc < 2) { help(); exit(0); } for(i = 1; i < argc; i++) { if(strcmp(argv[i], "-V") == 0) { printf("You are using %s./n", SERVER_NAME); exit(0); } else if((strcmp(argv[i], "--help") == 0) || (strcmp(argv[i], "-h") == 0)) { help(); exit(0); } else if((strcmp(argv[i], "--default-type") == 0) || (strcmp(argv[i], "-d") == 0)) { default_type = argv[i+1]; i++; } else if((strcmp(argv[i], "--headers") == 0) || (strcmp(argv[i], "-h") == 0)) { print_headers = 1; } else if((strcmp(argv[i], "-p") == 0) || (strcmp(argv[i], "--port") == 0)) { port = atoi(argv[i + 1]); i++; } else if((strcmp(argv[i], "-l") == 0) || (strcmp(argv[i], "--log") == 0)) { loglevel = 1; } else if(strcmp(argv[i], "-v") == 0) { verbose++; } else if(strcmp(argv[i], "-g") == 0) { generate_index = 1; } else if(strcmp(argv[i], "-s") == 0) { links = 1; } else if(strcmp(argv[i], "-b") == 0) { background = 1; } } dir = argv[argc - 1]; dirpnt = opendir(dir); if(dirpnt == NULL) { printf("Invalid directory - %s./n", dir); help(); exit(1); } if(background) { verbose = 0; rv = fork(); if(rv == -1) { crit("Error forking"); } else if(rv > 0) { /* Exit if this is the parent */ _exit(0); } if(setsid() == -1) crit("Couldn't create SID session."); if(signal(SIGCHLD, SIG_IGN) == SIG_ERR) { crit("Couldn't initialize signal handlers."); } if( (close(0) == -1) || (close(1) == -1) || (close(2) == -1)) { crit("Couldn't close streams."); } } while((curdir = readdir(dirpnt))) { flength = strlen(curdir->d_name) + strlen(dir) + 4; fullpath = (char *)smalloc(flength); snprintf(fullpath, flength + 2, "%s/%s", dir, curdir->d_name); if(links == 1) { rv = lstat(fullpath, &curstat); } else { rv = stat(fullpath, &curstat); } if(rv != 0) { fprintf(stderr, "Error statting file %s/%s/n", dir, curdir->d_name); continue; } /* Only use this file if it's not a link, directory, etc. */ if(S_ISREG(curstat.st_mode) && ( curdir->d_name[0] != '.' )) { if(files == NULL) { curfile = files = (void *)smalloc(sizeof(servable) + 2); } else { curfile = (void *)smalloc(sizeof(servable) + 2); } flength = strlen(curdir->d_name); curfile->filename = (void *)smalloc(flength + 2); strncpy(curfile->filename, curdir->d_name, flength + 1); curfile->fullpath = fullpath; curfile->next = NULL; curfile->content = NULL; if(lastfile == NULL) { lastfile = curfile; } else { lastfile->next = curfile; lastfile = curfile; } if(verbose) printf("Parsed %s as %s./n", fullpath, curfile->filename); } else { free(fullpath); } } /* Generate index */ if(generate_index == 1) index_page = gen_index(); #ifdef HAVE_SYS_SENDFILE_H if(verbose) printf("Using system's sendfile functionality./n"); #endif /* Trap signals */ if( (signal(SIGTERM, sigcatch) == SIG_ERR) || (signal(SIGINT, sigcatch) == SIG_ERR)) { crit("Couldn't setup signal traps."); } sockfd = socket (AF_INET, SOCK_STREAM, 0); if(sockfd == -1) crit("Couldn't create socket."); my_addr.sin_family = AF_INET; my_addr.sin_port = htons (port); my_addr.sin_addr.s_addr = INADDR_ANY; bzero (&(my_addr.sin_zero), 8); if (bind(sockfd, (struct sockaddr *) &my_addr, sizeof (struct sockaddr)) == -1) crit("Couldn't bind to specified port."); sin_size = sizeof(struct sockaddr_in); if(listen(sockfd, 25) == -1) crit("Couldn't listen on specified port."); if(verbose) printf("Listening for connections on port %d.../n", port); while(1) { newfd = accept(sockfd, (struct sockaddr *)&remote_addr, &sin_size); if(newfd == -1) crit("Couldn't accept connection!"); if(verbose) printf("Connected, handling request./n"); if(background) { fr = fork(); if(fr != 0) continue; handle_connection(newfd, (struct sockaddr_in *)&remote_addr); _exit(0); } handle_connection(newfd, (struct sockaddr_in *)&remote_addr); } } /* Cygwin doesn't like my time structures. It's on my todo list. */ #ifndef __CYGWIN__ static char * last_modified(time_t * stmtime) { struct tm * gmt; char * rv = (char *)smalloc(100); if((gmt = gmtime(stmtime)) == NULL) crit("gmtime() error."); if((strftime(rv, 95, "%a, %d %b %Y %T GMT", gmt)) == 0) crit("strftime() error."); return rv; } static char * curtime() { struct tm * gmt; char * rv = (char *)smalloc(100); time_t t = time(NULL); if((gmt = gmtime(&t)) == NULL) crit("gmtime() error."); if((strftime(rv, 95, "%d/%b/%Y:%T +0000", gmt)) == 0) crit("strftime() error."); return rv; } #else static char * last_modified(int mtime) { return NULL; } static char * curtime() { return "-"; } #endif static void handle_connection(int fd, struct sockaddr_in * remote) { handle_request(fd, remote); /* Shutdown socket */ if(shutdown(fd, SHUT_RDWR) == -1) { warn("Error shutting down client socket."); return; } if(close(fd) == -1) warn("Error closing client socket."); } static void loghit(char * req, char *referrer, char *ua, int code, int size, struct sockaddr_in * remote) { char * t = curtime(); char *i; if( (i = strchr(referrer, ' ')) == NULL) referrer = "-"; else referrer = i + 1; if( (i = strchr(ua, ' ')) == NULL) ua = "-"; else ua = i + 1; printf("%s - - [%s] - /"%s/" %d %d /"%s/" /"%s/"/n", inet_ntoa(remote->sin_addr), t, req, code, size, referrer, ua); fflush(stdout); if(t[0] != '-') free(t); } static void handle_request(int fd, struct sockaddr_in * remote) { int flength; int method; struct stat curstat; int rv, c, infd, h = 0; char inbuffer[2048]; char *out; char *lastmod; char outb[1024]; char * referrer = "-"; char * ua = ""; char * request = NULL; char * header; /* newline terminated header. */ int content_length = 0; servable * file; rv = recv(fd, inbuffer, sizeof(inbuffer), 0); if(rv == -1) { warn("Error receiving request from client."); return; } /** Read headers and request line. */ for(c = 0; c < rv; c++) { if(inbuffer[c] == '/n') { inbuffer[c] = '/0'; if((c > 1) && (inbuffer[c - 1] == '/r')) inbuffer[c-1] = '/0'; if(h != 0) { header = inbuffer + h; if(print_headers) printf("%s/n", header); if(strncmp(header, "Referer:", 8) == 0) referrer = header; if(strncmp(header, "User-Agent:", 11) == 0) ua = header; } else { request = inbuffer; if(print_headers) printf("%s/n", request); } h = c + 1; } } if(request == NULL) { return; /* TODO: Return error */ } if(verbose) printf("REQ: %s/n", request); method = get_method(request); /* Find file in linked list */ file = match_request(request); if(file == NULL) { out = "HTTP/1.0 404 Not Found/r/n"; if(safesend(fd, out) == -1) return; snprintf(outb, sizeof(outb), "Server: %s/%s/r/n", SERVER_NAME, VERSION); if(safesend(fd, outb) == -1) return; if(method = METHOD_GET) { out = "Content-Type: text/html; charset=iso-8859-1/r/n"; if(safesend(fd, out) == -1) return; snprintf(outb, sizeof(outb), "Content-Length: %d/r/n", strlen(msg404)); if(safesend(fd, outb) == -1) return; // Send error response c = strlen(msg404); if(safesend(fd, msg404) == -1) return; } snprintf(outb, sizeof(outb), "/r/n"); if(safesend(fd, outb) == -1) return; if(loglevel) loghit(request, referrer, ua, 404, c, remote); return; } /* Response status line */ out = "HTTP/1.0 200 OK/r/n"; if(safesend(fd, out) == -1) return; if(file->filename != NULL) { /* Get file stats */ if(lstat(file->fullpath, &curstat) == -1) { warn("Error checking file."); return; } /* Response headers */ snprintf(outb, sizeof(outb), "Content-Type: %s/r/n", get_mimetype(file->filename)); if(safesend(fd, outb) == -1) return; lastmod = last_modified(&curstat.st_mtime); if(lastmod != NULL) { snprintf(outb, sizeof(outb), "Last-modified: %s/r/n", lastmod); if(safesend(fd, outb) == -1) return; free(lastmod); } if(method == METHOD_GET) { snprintf(outb, sizeof(outb), "Content-Length: %d/r/n", (int)curstat.st_size); if(safesend(fd, outb) == -1) return; } snprintf(outb, sizeof(outb), "Server: %s/%s/r/n/r/n", SERVER_NAME, VERSION); if(safesend(fd, outb) == -1) return; /* Response content */ if(method == METHOD_GET) { infd = open(file->fullpath, O_RDONLY); if(infd == -1) { printf("Couldn't open %s, error %d/n", file->fullpath, errno); return; } #ifdef HAVE_SYS_SENDFILE_H if(sendfile(fd, infd, 0, curstat.st_size) == -1) { warn("Error sending response to client."); return; } #else while((rv = read(infd, outb, sizeof(outb)) ) != 0) { if(write(fd, outb, rv) == -1) { warn("Error sending response to client."); return; } } #endif close(infd); } if(loglevel) loghit(request, referrer, ua, 200, curstat.st_size, remote); } else { /* Use our internal file */ content_length = 0; if(method == METHOD_GET) { content_length = file->content_length; } if(file->last_modified != 0) { snprintf(outb, sizeof(outb), "Last-Modified: %s/r/n", file->last_modified); if(safesend(fd, outb) == -1) return; } snprintf(outb, sizeof(outb), "Content-Type: %s/r/nContent-Length: %d/r/n/r/n", file->content_type, content_length); if(safesend(fd, outb) == -1) return; if(loglevel) loghit(request, referrer, ua, 200, file->content_length, remote); if(method == METHOD_GET) { if(safesend(fd, file->content) == -1) return; } } } static int get_method(char * req) { if(strncasecmp(req, "GET", 3) == 0) { return METHOD_GET; } if(strncasecmp(req, "HEAD", 4) == 0) { return METHOD_HEAD; } return METHOD_UNSUPPORTED; } static servable * gen_index() { servable * myi = NULL; servable * ptr = files; char * content = NULL; /* Big ass embedded string. I know, it be ugly. */ char * st = "<!DOCTYPE html PUBLIC /"-//W3C//DTD XHTML 1.0 Transitional//EN/" /"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd/">/r/n/r/n<html><head><title>Index of /</title></head><body><h2>Index of /</h2><ul>/n"; char * en = "</ul><p><i>Powered by <a href="/" mce_href="/""http://www.neuro-tech.net/cheetah/">Cheetah</a></i>.</body></html>/n"; int sz = 0; myi = smalloc(sizeof(servable) + 2); myi->filename = NULL; myi->fullpath = NULL; sz = strlen(st) + strlen(en); content = smalloc(sz + 2); strncpy(content, st, sz + 1); /* Might be slow, but it's only run once. */ while(ptr != NULL) { sz += (strlen(ptr->filename)) * 2; sz += 40; if(!realloc(content, sz)) { printf("Memory allocation error./n"); exit(0); } strcat(content, "<li><a href="/" mce_href="/"""); strcat(content, ptr->filename); strcat(content, "/">"); strcat(content, ptr->filename); strcat(content, "</a></li>/n"); ptr = ptr->next; } strcat(content, en); myi->content = content; myi->content_length = strlen(content); myi->content_type = "text/html"; myi->last_modified = NULL; return myi; } static servable * match_request(char * req) { servable * rv = NULL; char uri[1024]; char * u; int c; int in = 0; int ptr = 0; /* Parse filename */ for(c = 0; c < strlen(req); c++) { if(in == 1) uri[ptr++] = req[c]; if((in == 2) || (ptr > 1000)) break; if(req[c] == ' ') in++; } uri[ptr] = '/0'; u = uri; if(strcmp(uri, "/ ") == 0) { if(generate_index == 1) { return index_page; } else { strncpy(uri, "/index.html", sizeof(uri)); } } if(uri[0] == '/') u++; if(verbose) printf("Checking for /"%s/"/n", u); if(files == NULL) { return NULL; } rv = files; while(1) { if(strncmp(u, rv->filename, strlen(rv->filename)) == 0) return rv; if(rv->next == NULL) return NULL; rv = rv->next; } return NULL; } static int safesend(int fd, char * out) { int rv; if((rv = send(fd, out, strlen(out), 0)) == -1) { warn("Error sending data to client."); } return rv; } static void sigcatch(int signal) { if(verbose) printf("Signal caught, exiting./n"); if(sockfd != -1) { close(sockfd); exit(0); } } static char * get_mimetype(char * file) { char * comp; for(comp = file + strlen(file); comp > file; comp--) { if(comp[0] == '.') { comp++; if(strcasecmp(comp, "html") == 0) return "text/html"; if(strcasecmp(comp, "gif") == 0) return "image/gif"; if(strcasecmp(comp, "jpg") == 0) return "image/jpeg"; if(strcasecmp(comp, "png") == 0) return "image/png"; if(strcasecmp(comp, "css") == 0) return "text/css"; return default_type; } } return default_type; } static void crit(char * message) { fprintf(stderr, "%s/n", message); exit(1); } static void warn(char * message) { fprintf(stderr, "%s/n", message); } static void * smalloc(size_t size) { void * rv = malloc(size); if(rv == NULL) crit("Memory allocation error."); return rv; }