/*************************************************************************** handle a file download ***************************************************************************/ static void cgi_download(char *file) { struct stat st; char buf[1024]; int fd, l, i; char *p; /* sanitise the filename */ for (i=0;file[i];i++) { if (!isalnum(file[i]) && !strchr("/.-_", file[i])) { cgi_setup_error("404 File Not Found","", "Illegal character in filename"); } } if (strstr(file,"..")) { cgi_setup_error("404 File Not Found","", "Relative paths not allowed"); } if (!file_exist(file, &st)) { cgi_setup_error("404 File Not Found","", "The requested file was not found"); } fd = open(file,O_RDONLY); if (fd == -1) { cgi_setup_error("404 File Not Found","", "The requested file was not found"); } printf("HTTP/1.1 200 OK\r\n"); if ((p=strrchr(file,'.'))) { if (strcmp(p,".gif")==0 || strcmp(p,".jpg")==0) { printf("Content-Type: image/gif\r\n"); } else { printf("Content-Type: text/html\r\n"); } } printf("Content-Length: %d\r\n\r\n", (int)st.st_size); while ((l=read(fd,buf,sizeof(buf)))>0) { fwrite(buf, 1, l, stdout); } close(fd); exit(0); }
/*************************************************************************** handle a http authentication line ***************************************************************************/ static int cgi_handle_authorization(char *line) { char *p, *user, *pass; struct passwd *pwd; int ret=0; if (strncasecmp(line,"Basic ", 6)) { cgi_setup_error("401 Bad Authorization", "", "Only basic authorization is understood"); } line += 6; while (line[0] == ' ') line++; base64_decode(line); if (!(p=strchr(line,':'))) { cgi_setup_error("401 Bad Authorization", "", "username/password must be supplied"); } *p = 0; user = line; pass = p+1; /* currently only allow connections as root */ if (strcasecmp(user,"root")) { cgi_setup_error("401 Bad Authorization", "", "incorrect username/password"); } pwd = getpwnam(user); if (!strcmp((char *)crypt(pass, pwd->pw_passwd),pwd->pw_passwd)) { ret = 1; } memset(pass, 0, strlen(pass)); return ret; }
/*************************************************************************** tell a browser about a fatal authentication error ***************************************************************************/ static void cgi_auth_error(void) { if (inetd_server) { cgi_setup_error("401 Authorization Required", "WWW-Authenticate: Basic realm=\"SWAT\"\r\n", "You must be authenticated to use this service"); } else { printf("Content-Type: text/html\r\n"); printf("\r\n<HTML><HEAD><TITLE>SWAT</TITLE></HEAD>\n"); printf("<BODY><H1>Installation Error</H1>\n"); printf("SWAT must be installed via inetd. It cannot be run as a CGI script<p>\n"); printf("</BODY></HTML>\r\n"); } exit(0); }
/*************************************************************************** setup the cgi framework, handling the possability that this program is either run as a true cgi program by a web browser or is itself a mini web server ***************************************************************************/ void cgi_setup(char *rootdir) { int authenticated = 0; char line[1024]; char *url=NULL; char *p; if (chdir(rootdir)) { cgi_setup_error("400 Server Error", "", "chdir failed - the server is not configured correctly"); } if (getenv("CONTENT_LENGTH") || getenv("REQUEST_METHOD")) { /* assume we are running under a real web server */ return; } /* we are a mini-web server. We need to read the request from stdin and handle authentication etc */ while (fgets(line, sizeof(line)-1, stdin)) { if (line[0] == '\r' || line[0] == '\n') break; if (strncasecmp(line,"GET ", 4)==0) { request_get = 1; url = strdup(&line[4]); } else if (strncasecmp(line,"POST ", 5)==0) { request_post = 1; url = strdup(&line[5]); } else if (strncasecmp(line,"PUT ", 4)==0) { cgi_setup_error("400 Bad Request", "", "This server does not accept PUT requests"); } else if (strncasecmp(line,"Authorization: ", 15)==0) { authenticated = cgi_handle_authorization(&line[15]); } else if (strncasecmp(line,"Content-Length: ", 16)==0) { content_length = atoi(&line[16]); } /* ignore all other requests! */ } if (!authenticated) { cgi_setup_error("401 Authorization Required", "WWW-Authenticate: Basic realm=\"root\"\r\n", "You must be authenticated to use this service"); } if (!url) { cgi_setup_error("400 Bad Request", "", "You must specify a GET or POST request"); } /* trim the URL */ if ((p = strchr(url,' ')) || (p=strchr(url,'\t'))) { *p = 0; } while (*url && strchr("\r\n",url[strlen(url)-1])) { url[strlen(url)-1] = 0; } /* anything following a ? in the URL is part of the query string */ if ((p=strchr(url,'?'))) { query_string = p+1; *p = 0; } if (strcmp(url,"/")) { cgi_download(url+1); } printf("HTTP/1.1 200 OK\r\nConnection: close\r\n"); }
/** * @brief Setup the CGI framework. * * Setup the cgi framework, handling the possibility that this program * is either run as a true CGI program with a gateway to a web server, or * is itself a mini web server. **/ void cgi_setup(const char *rootdir, int auth_required) { bool authenticated = False; char line[1024]; char *url=NULL; char *p; char *lang; if (chdir(rootdir)) { cgi_setup_error("500 Server Error", "", "chdir failed - the server is not configured correctly"); } /* Handle the possibility we might be running as non-root */ sec_init(); if ((lang=getenv("HTTP_ACCEPT_LANGUAGE"))) { /* if running as a cgi program */ web_set_lang(lang); } /* maybe we are running under a web server */ if (getenv("CONTENT_LENGTH") || getenv("REQUEST_METHOD")) { if (auth_required) { cgi_web_auth(); } return; } inetd_server = True; if (!check_access(1, lp_hostsallow(-1), lp_hostsdeny(-1))) { cgi_setup_error("403 Forbidden", "", "Samba is configured to deny access from this client\n<br>Check your \"hosts allow\" and \"hosts deny\" options in smb.conf "); } /* we are a mini-web server. We need to read the request from stdin and handle authentication etc */ while (fgets(line, sizeof(line)-1, stdin)) { if (line[0] == '\r' || line[0] == '\n') break; if (strnequal(line,"GET ", 4)) { got_request = True; url = SMB_STRDUP(&line[4]); } else if (strnequal(line,"POST ", 5)) { got_request = True; request_post = 1; url = SMB_STRDUP(&line[5]); } else if (strnequal(line,"PUT ", 4)) { got_request = True; cgi_setup_error("400 Bad Request", "", "This server does not accept PUT requests"); } else if (strnequal(line,"Authorization: ", 15)) { authenticated = cgi_handle_authorization(&line[15]); } else if (strnequal(line,"Content-Length: ", 16)) { content_length = atoi(&line[16]); } else if (strnequal(line,"Accept-Language: ", 17)) { web_set_lang(&line[17]); } /* ignore all other requests! */ } if (auth_required && !authenticated) { cgi_auth_error(); } if (!url) { cgi_setup_error("400 Bad Request", "", "You must specify a GET or POST request"); } /* trim the URL */ if ((p = strchr_m(url,' ')) || (p=strchr_m(url,'\t'))) { *p = 0; } while (*url && strchr_m("\r\n",url[strlen(url)-1])) { url[strlen(url)-1] = 0; } /* anything following a ? in the URL is part of the query string */ if ((p=strchr_m(url,'?'))) { query_string = p+1; *p = 0; } string_sub(url, "/swat/", "", 0); if (url[0] != '/' && strstr(url,"..")==0) { cgi_download(url); } printf("HTTP/1.0 200 OK\r\nConnection: close\r\n"); printf("Date: %s\r\n", http_timestring(time(NULL))); baseurl = ""; pathinfo = url+1; }
/*************************************************************************** handle a file download ***************************************************************************/ static void cgi_download(char *file) { SMB_STRUCT_STAT st; char buf[1024]; int fd, l, i; char *p; char *lang; /* sanitise the filename */ for (i=0;file[i];i++) { if (!isalnum((int)file[i]) && !strchr_m("/.-_", file[i])) { cgi_setup_error("404 File Not Found","", "Illegal character in filename"); } } if (sys_stat(file, &st) != 0) { cgi_setup_error("404 File Not Found","", "The requested file was not found"); } if (S_ISDIR(st.st_mode)) { snprintf(buf, sizeof(buf), "%s/index.html", file); if (!file_exist(buf, &st) || !S_ISREG(st.st_mode)) { cgi_setup_error("404 File Not Found","", "The requested file was not found"); } } else if (S_ISREG(st.st_mode)) { snprintf(buf, sizeof(buf), "%s", file); } else { cgi_setup_error("404 File Not Found","", "The requested file was not found"); } fd = web_open(buf,O_RDONLY,0); if (fd == -1) { cgi_setup_error("404 File Not Found","", "The requested file was not found"); } printf("HTTP/1.0 200 OK\r\n"); if ((p=strrchr_m(buf, '.'))) { if (strcmp(p,".gif")==0) { printf("Content-Type: image/gif\r\n"); } else if (strcmp(p,".jpg")==0) { printf("Content-Type: image/jpeg\r\n"); } else if (strcmp(p,".png")==0) { printf("Content-Type: image/png\r\n"); } else if (strcmp(p,".css")==0) { printf("Content-Type: text/css\r\n"); } else if (strcmp(p,".txt")==0) { printf("Content-Type: text/plain\r\n"); } else { printf("Content-Type: text/html\r\n"); } } printf("Expires: %s\r\n", http_timestring(time(NULL)+EXPIRY_TIME)); lang = lang_tdb_current(); if (lang) { printf("Content-Language: %s\r\n", lang); } printf("Content-Length: %d\r\n\r\n", (int)st.st_size); while ((l=read(fd,buf,sizeof(buf)))>0) { if (fwrite(buf, 1, l, stdout) != l) { break; } } close(fd); exit(0); }
/*************************************************************************** handle a http authentication line ***************************************************************************/ static bool cgi_handle_authorization(char *line) { char *p; fstring user, user_pass; struct passwd *pass = NULL; if (!strnequal(line,"Basic ", 6)) { goto err; } line += 6; while (line[0] == ' ') line++; base64_decode_inplace(line); if (!(p=strchr_m(line,':'))) { /* * Always give the same error so a cracker * cannot tell why we fail. */ goto err; } *p = 0; convert_string(CH_UTF8, CH_UNIX, line, -1, user, sizeof(user), True); convert_string(CH_UTF8, CH_UNIX, p+1, -1, user_pass, sizeof(user_pass), True); /* * Try and get the user from the UNIX password file. */ pass = getpwnam_alloc(talloc_autofree_context(), user); /* * Validate the password they have given. */ if NT_STATUS_IS_OK(pass_check(pass, user, user_pass, strlen(user_pass), NULL, False)) { if (pass) { /* * Password was ok. */ if ( initgroups(pass->pw_name, pass->pw_gid) != 0 ) goto err; become_user_permanently(pass->pw_uid, pass->pw_gid); /* Save the users name */ C_user = SMB_STRDUP(user); TALLOC_FREE(pass); return True; } } err: cgi_setup_error("401 Bad Authorization", "WWW-Authenticate: Basic realm=\"SWAT\"\r\n", "username or password incorrect"); TALLOC_FREE(pass); return False; }