@cryptotaxi247 / netdata-1 / commits / 81a61a59f

added option to allow running as a user and serving files owned by another; added support for serving files in directories within the netdata web dir

Costa Tsaousis (ktsaou) committed Nov 28, 2015 at 15:59 UTC 81a61a59f6344651801aa58268ce2dba9596ccb1

3 files changed +75 -35

src/main.c

+2 -1

@@ -368,7 +368,8 @@ int main(int argc, char **argv)

368 // --------------------------------------------------------------------

369

370 prepare_rundir();

371 - user = config_get("global", "run as user", (getuid() == 0)?NETDATA_USER:"");

371 + user = config_get("global", "run as user" , (getuid() == 0)?NETDATA_USER:"");

372 + web_files_uid();

373

374 // --------------------------------------------------------------------

375

src/web_client.c

+69 -34

@@ -13,6 +13,7 @@

13 #include <fcntl.h>

14 #include <netinet/tcp.h>

15 #include <malloc.h>

16 +#include <pwd.h>

18 #include "common.h"

19 #include "log.h"

@@ -146,14 +147,15 @@ void web_client_reset(struct web_client *w)

147 long size = (w->mode == WEB_CLIENT_MODE_FILECOPY)?w->response.rlen:w->response.data->len;

148

149 if(likely(w->last_url[0]))

149 - log_access("%llu: (sent/all = %ld/%ld bytes %0.0f%%, prep/sent/total = %0.2f/%0.2f/%0.2f ms) %s: '%s'",

150 + log_access("%llu: (sent/all = %ld/%ld bytes %0.0f%%, prep/sent/total = %0.2f/%0.2f/%0.2f ms) %s: %d '%s'",

151 w->id,

152 sent, size, -((size>0)?((float)(size-sent)/(float)size * 100.0):0.0),

153 (float)usecdiff(&w->tv_ready, &w->tv_in) / 1000.0,

154 (float)usecdiff(&tv, &w->tv_ready) / 1000.0,

155 (float)usecdiff(&tv, &w->tv_in) / 1000.0,

156 (w->mode == WEB_CLIENT_MODE_FILECOPY)?"filecopy":"data",

156 - w->last_url

157 + w->response.code,

158 + w->last_url

159 );

160

161 debug(D_WEB_CLIENT, "%llu: Reseting client.", w->id);

@@ -173,6 +175,7 @@ void web_client_reset(struct web_client *w)

175 buffer_reset(w->response.data);

176 w->response.rlen = 0;

177 w->response.sent = 0;

178 + w->response.code = 0;

179

180 w->wait_receive = 1;

181 w->wait_send = 0;

@@ -217,26 +220,59 @@ struct web_client *web_client_free(struct web_client *w)

220 return(n);

221 }

222

223 +uid_t web_files_uid(void)

224 +{

225 + static char *web_owner = NULL;

226 + static uid_t owner_uid = 0;

227 +

228 + if(unlikely(!web_owner)) {

229 + web_owner = config_get("global", "web files owner", NETDATA_USER);

230 + if(!web_owner || !*web_owner)

231 + owner_uid = geteuid();

232 + else {

233 + struct passwd *pw = getpwnam(web_owner);

234 + if(!pw) {

235 + error("User %s is not present. Ignoring option. Error: %s\n", web_owner, strerror(errno));

236 + owner_uid = geteuid();

237 + }

238 + else {

239 + debug(D_WEB_CLIENT, "Web files owner set to %s.\n", web_owner);

240 + owner_uid = pw->pw_uid;

241 + }

242 + }

243 + }

244 +

245 + return(owner_uid);

246 +}

247 +

248 int mysendfile(struct web_client *w, char *filename)

249 {

250 static char *web_dir = NULL;

223 - if(!web_dir) web_dir = config_get("global", "web files directory", WEB_DIR);

251

225 - debug(D_WEB_CLIENT, "%llu: Looking for file '%s'...", w->id, filename);

252 + // initialize our static data

253 + if(unlikely(!web_dir)) web_dir = config_get("global", "web files directory", WEB_DIR);

254 +

255 + debug(D_WEB_CLIENT, "%llu: Looking for file '%s/%s'", w->id, web_dir, filename);

256

257 // skip leading slashes

258 while (*filename == '/') filename++;

259

260 // if the filename contain known paths, skip them

231 - if(strncmp(filename, WEB_PATH_DATA "/", strlen(WEB_PATH_DATA) + 1) == 0) filename = &filename[strlen(WEB_PATH_DATA) + 1];

232 - else if(strncmp(filename, WEB_PATH_DATASOURCE "/", strlen(WEB_PATH_DATASOURCE) + 1) == 0) filename = &filename[strlen(WEB_PATH_DATASOURCE) + 1];

233 - else if(strncmp(filename, WEB_PATH_GRAPH "/", strlen(WEB_PATH_GRAPH) + 1) == 0) filename = &filename[strlen(WEB_PATH_GRAPH) + 1];

234 - else if(strncmp(filename, WEB_PATH_FILE "/", strlen(WEB_PATH_FILE) + 1) == 0) filename = &filename[strlen(WEB_PATH_FILE) + 1];

261 + if(strncmp(filename, WEB_PATH_FILE "/", strlen(WEB_PATH_FILE) + 1) == 0) filename = &filename[strlen(WEB_PATH_FILE) + 1];

262 +

263 + char *s;

264 + for(s = filename; *s ;s++) {

265 + if( !isalnum(*s) && *s != '/' && *s != '.' && *s != '-' && *s != '_') {

266 + debug(D_WEB_CLIENT_ACCESS, "%llu: File '%s' is not acceptable.", w->id, filename);

267 + buffer_sprintf(w->response.data, "File '%s' cannot be served. Filename contains invalid character '%c'", *s);

268 + return 400;

269 + }

270 + }

271

236 - // if the filename contains a / or a .., refuse to serve it

237 - if(strchr(filename, '/') != 0 || strstr(filename, "..") != 0) {

272 + // if the filename contains a .. refuse to serve it

273 + if(strstr(filename, "..") != 0) {

274 debug(D_WEB_CLIENT_ACCESS, "%llu: File '%s' is not acceptable.", w->id, filename);

239 - buffer_sprintf(w->response.data, "File '%s' cannot be served. Filenames cannot contain / or ..", filename);

275 + buffer_sprintf(w->response.data, "File '%s' cannot be served. Relative filenames with '..' in them are not supported.", filename);

276 return 400;

277 }

278

@@ -247,14 +283,25 @@ int mysendfile(struct web_client *w, char *filename)

283 // check if the file exists

284 struct stat stat;

285 if(lstat(webfilename, &stat) != 0) {

250 - error("%llu: File '%s' is not found.", w->id, webfilename);

286 + debug(D_WEB_CLIENT_ACCESS, "%llu: File '%s' is not found.", w->id, webfilename);

287 buffer_sprintf(w->response.data, "File '%s' does not exist, or is not accessible.", filename);

288 return 404;

289 }

290

291 // check if the file is owned by us

256 - if(stat.st_uid != getuid() && stat.st_uid != geteuid()) {

257 - error("%llu: File '%s' is owned by user %d (I run as user %d). Access Denied.", w->id, webfilename, stat.st_uid, getuid());

292 + if(stat.st_uid != web_files_uid()) {

293 + debug(D_WEB_CLIENT_ACCESS, "%llu: File '%s' is owned by user %d (I run as user %d). Access Denied.", w->id, webfilename, stat.st_uid, getuid());

294 + buffer_sprintf(w->response.data, "Access to file '%s' is not permitted.", filename);

295 + return 403;

296 + }

297 +

298 + if((stat.st_mode & S_IFMT) == S_IFDIR) {

299 + snprintf(webfilename, FILENAME_MAX+1, "%s/index.html", filename);

300 + return mysendfile(w, webfilename);

301 + }

302 +

303 + if((stat.st_mode & S_IFMT) != S_IFREG) {

304 + debug(D_WEB_CLIENT_ACCESS, "%llu: File '%s' is not a regular file. Access Denied.", w->id, webfilename);

305 buffer_sprintf(w->response.data, "Access to file '%s' is not permitted.", filename);

306 return 403;

307 }

@@ -794,7 +841,7 @@ void web_client_process(struct web_client *w) {

841 strncpy(w->last_url, url, URL_MAX);

842 w->last_url[URL_MAX] = '\0';

843

797 - tok = mystrsep(&url, "/?&");

844 + tok = mystrsep(&url, "/?");

845

846 debug(D_WEB_CLIENT, "%llu: Processing command '%s'.", w->id, tok);

847

@@ -897,24 +944,15 @@ void web_client_process(struct web_client *w) {

944 buffer_flush(w->response.data);

945 generate_config(w->response.data, 0);

946 }

900 - else if(strcmp(tok, WEB_PATH_FILE) == 0) { // "file"

901 - tok = mystrsep(&url, "/?&");

902 - if(tok && *tok) code = mysendfile(w, tok);

903 - else {

904 - code = 400;

905 - buffer_flush(w->response.data);

906 - buffer_strcat(w->response.data, "You have to give a filename to get.\r\n");

907 - }

908 - }

909 - else if(!tok[0]) {

910 - buffer_flush(w->response.data);

911 - code = mysendfile(w, "index.html");

912 - }

947 else {

948 + char filename[FILENAME_MAX+1];

949 + url = filename;

950 + strncpy(filename, w->last_url, FILENAME_MAX);

951 + filename[FILENAME_MAX] = '\0';

952 + tok = mystrsep(&url, "?");

953 buffer_flush(w->response.data);

915 - code = mysendfile(w, tok);

954 + code = mysendfile(w, (tok && *tok)?tok:"/");

955 }

917 -

956 }

957 else {

958 strcpy(w->last_url, "not a valid response");

@@ -944,13 +982,10 @@ void web_client_process(struct web_client *w) {

982 return;

983 }

984

947 - if(w->response.data->len > w->response.data->size) {

948 - error("%llu: memory overflow encountered (size is %ld, written %ld).", w->response.data->size, w->response.data->len);

949 - }

950 -

985 gettimeofday(&w->tv_ready, NULL);

986 w->response.data->date = time(NULL);

987 w->response.sent = 0;

988 + w->response.code = code;

989

990 // prepare the HTTP response header

991 debug(D_WEB_CLIENT, "%llu: Generating HTTP header with response %d.", w->id, code);

src/web_client.h

@@ -31,6 +31,8 @@ struct response {

31 BUFFER *header_output; // internal use

32 BUFFER *data; // our response data buffer

34 + int code; // the HTTP response code

35 +

36 long rlen; // if non-zero, the excepted size of ifd (input)

37 long sent; // current data length sent to output

@@ -77,6 +79,8 @@ struct web_client {

80 extern struct web_client *web_clients;

82 +extern uid_t web_files_uid(void);

83 +

84 extern struct web_client *web_client_create(int listener);

85 extern struct web_client *web_client_free(struct web_client *w);