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- /* Copyright 2003 Roger Dingledine */
- /* See LICENSE for licensing information */
- /* $Id$ */
- #include "../or/or.h"
- #ifdef HAVE_UNAME
- #include <sys/utsname.h>
- #endif
- /* used by inet_addr, not defined on solaris anywhere!? */
- #ifndef INADDR_NONE
- #define INADDR_NONE ((unsigned long) -1)
- #endif
- /* in-line the strl functions */
- #ifndef HAVE_STRLCPY
- #include "strlcpy.c"
- #endif
- #ifndef HAVE_STRLCAT
- #include "strlcat.c"
- #endif
- /*
- * Memory wrappers
- */
- void *tor_malloc(size_t size) {
- void *result;
- result = malloc(size);
- if(!result) {
- log_fn(LOG_ERR, "Out of memory. Dying.");
- exit(1);
- }
- // memset(result,'X',size); /* deadbeef to encourage bugs */
- return result;
- }
- void *tor_malloc_zero(size_t size) {
- void *result = tor_malloc(size);
- memset(result, 0, size);
- return result;
- }
- void *tor_realloc(void *ptr, size_t size) {
- void *result;
- result = realloc(ptr, size);
- if (!result) {
- log_fn(LOG_ERR, "Out of memory. Dying.");
- exit(1);
- }
- return result;
- }
- char *tor_strdup(const char *s) {
- char *dup;
- assert(s);
- dup = strdup(s);
- if(!dup) {
- log_fn(LOG_ERR,"Out of memory. Dying.");
- exit(1);
- }
- return dup;
- }
- char *tor_strndup(const char *s, size_t n) {
- char *dup;
- assert(s);
- dup = tor_malloc(n+1);
- strncpy(dup, s, n);
- dup[n] = 0;
- return dup;
- }
- /*
- * A simple smartlist interface to make an unordered list of acceptable
- * nodes and then choose a random one.
- * smartlist_create() mallocs the list, _free() frees the list,
- * _add() adds an element, _remove() removes an element if it's there,
- * _choose() returns a random element.
- */
- smartlist_t *smartlist_create(int max_elements) {
- smartlist_t *sl = tor_malloc(sizeof(smartlist_t));
- sl->list = tor_malloc(sizeof(void *) * max_elements);
- sl->num_used = 0;
- sl->max = max_elements;
- return sl;
- }
- void smartlist_free(smartlist_t *sl) {
- free(sl->list);
- free(sl);
- }
- /* add element to the list, but only if there's room */
- void smartlist_add(smartlist_t *sl, void *element) {
- if(sl->num_used < sl->max)
- sl->list[sl->num_used++] = element;
- else
- log_fn(LOG_WARN,"We've already got %d elements, discarding.",sl->max);
- }
- void smartlist_remove(smartlist_t *sl, void *element) {
- int i;
- if(element == NULL)
- return;
- for(i=0; i < sl->num_used; i++)
- if(sl->list[i] == element) {
- sl->list[i] = sl->list[--sl->num_used]; /* swap with the end */
- i--; /* so we process the new i'th element */
- }
- }
- int smartlist_isin(smartlist_t *sl, void *element) {
- int i;
- for(i=0; i < sl->num_used; i++)
- if(sl->list[i] == element)
- return 1;
- return 0;
- }
- int smartlist_overlap(smartlist_t *sl1, smartlist_t *sl2) {
- int i;
- for(i=0; i < sl2->num_used; i++)
- if(smartlist_isin(sl1, sl2->list[i]))
- return 1;
- return 0;
- }
- /* remove elements of sl1 that aren't in sl2 */
- void smartlist_intersect(smartlist_t *sl1, smartlist_t *sl2) {
- int i;
- for(i=0; i < sl1->num_used; i++)
- if(!smartlist_isin(sl2, sl1->list[i])) {
- sl1->list[i] = sl1->list[--sl1->num_used]; /* swap with the end */
- i--; /* so we process the new i'th element */
- }
- }
- /* remove all elements of sl2 from sl1 */
- void smartlist_subtract(smartlist_t *sl1, smartlist_t *sl2) {
- int i;
- for(i=0; i < sl2->num_used; i++)
- smartlist_remove(sl1, sl2->list[i]);
- }
- void *smartlist_choose(smartlist_t *sl) {
- if(sl->num_used)
- return sl->list[crypto_pseudo_rand_int(sl->num_used)];
- return NULL; /* no elements to choose from */
- }
- /*
- * String manipulation
- */
- /* return the first char of s that is not whitespace and not a comment */
- const char *eat_whitespace(const char *s) {
- assert(s);
- while(isspace((int)*s) || *s == '#') {
- while(isspace((int)*s))
- s++;
- if(*s == '#') { /* read to a \n or \0 */
- while(*s && *s != '\n')
- s++;
- if(!*s)
- return s;
- }
- }
- return s;
- }
- const char *eat_whitespace_no_nl(const char *s) {
- while(*s == ' ' || *s == '\t')
- ++s;
- return s;
- }
- /* return the first char of s that is whitespace or '#' or '\0 */
- const char *find_whitespace(const char *s) {
- assert(s);
- while(*s && !isspace((int)*s) && *s != '#')
- s++;
- return s;
- }
- /*
- * Time
- */
- void tor_gettimeofday(struct timeval *timeval) {
- #ifdef HAVE_GETTIMEOFDAY
- if (gettimeofday(timeval, NULL)) {
- log_fn(LOG_ERR, "gettimeofday failed.");
- /* If gettimeofday dies, we have either given a bad timezone (we didn't),
- or segfaulted.*/
- exit(1);
- }
- #elif defined(HAVE_FTIME)
- ftime(timeval);
- #else
- #error "No way to get time."
- #endif
- return;
- }
- long
- tv_udiff(struct timeval *start, struct timeval *end)
- {
- long udiff;
- long secdiff = end->tv_sec - start->tv_sec;
- if (secdiff+1 > LONG_MAX/1000000) {
- log_fn(LOG_WARN, "comparing times too far apart.");
- return LONG_MAX;
- }
- udiff = secdiff*1000000L + (end->tv_usec - start->tv_usec);
- if(udiff < 0) {
- log_fn(LOG_INFO, "start (%ld.%ld) is after end (%ld.%ld). Returning 0.",
- (long)start->tv_sec, (long)start->tv_usec, (long)end->tv_sec, (long)end->tv_usec);
- return 0;
- }
- return udiff;
- }
- int tv_cmp(struct timeval *a, struct timeval *b) {
- if (a->tv_sec > b->tv_sec)
- return 1;
- if (a->tv_sec < b->tv_sec)
- return -1;
- if (a->tv_usec > b->tv_usec)
- return 1;
- if (a->tv_usec < b->tv_usec)
- return -1;
- return 0;
- }
- void tv_add(struct timeval *a, struct timeval *b) {
- a->tv_usec += b->tv_usec;
- a->tv_sec += b->tv_sec + (a->tv_usec / 1000000);
- a->tv_usec %= 1000000;
- }
- void tv_addms(struct timeval *a, long ms) {
- a->tv_usec += (ms * 1000) % 1000000;
- a->tv_sec += ((ms * 1000) / 1000000) + (a->tv_usec / 1000000);
- a->tv_usec %= 1000000;
- }
- #define IS_LEAPYEAR(y) (!(y % 4) && ((y % 100) || !(y % 400)))
- static int n_leapdays(int y1, int y2) {
- --y1;
- --y2;
- return (y2/4 - y1/4) - (y2/100 - y1/100) + (y2/400 - y1/400);
- }
- static const int days_per_month[] =
- { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
- time_t tor_timegm (struct tm *tm) {
- /* This is a pretty ironclad timegm implementation, snarfed from Python2.2.
- * It's way more brute-force than fiddling with tzset().
- */
- time_t ret;
- unsigned long year, days, hours, minutes;
- int i;
- year = tm->tm_year + 1900;
- assert(year >= 1970);
- assert(tm->tm_mon >= 0 && tm->tm_mon <= 11);
- days = 365 * (year-1970) + n_leapdays(1970,year);
- for (i = 0; i < tm->tm_mon; ++i)
- days += days_per_month[i];
- if (tm->tm_mon > 1 && IS_LEAPYEAR(year))
- ++days;
- days += tm->tm_mday - 1;
- hours = days*24 + tm->tm_hour;
- minutes = hours*60 + tm->tm_min;
- ret = minutes*60 + tm->tm_sec;
- return ret;
- }
- /*
- * Low-level I/O.
- */
- /* a wrapper for write(2) that makes sure to write all count bytes.
- * Only use if fd is a blocking fd. */
- int write_all(int fd, const char *buf, size_t count, int isSocket) {
- size_t written = 0;
- int result;
- while(written != count) {
- if (isSocket)
- result = send(fd, buf+written, count-written, 0);
- else
- result = write(fd, buf+written, count-written);
- if(result<0)
- return -1;
- written += result;
- }
- return count;
- }
- /* a wrapper for read(2) that makes sure to read all count bytes.
- * Only use if fd is a blocking fd. */
- int read_all(int fd, char *buf, size_t count, int isSocket) {
- size_t numread = 0;
- int result;
- while(numread != count) {
- if (isSocket)
- result = recv(fd, buf+numread, count-numread, 0);
- else
- result = read(fd, buf+numread, count-numread);
- if(result<=0)
- return -1;
- numread += result;
- }
- return count;
- }
- void set_socket_nonblocking(int socket)
- {
- #ifdef MS_WINDOWS
- /* Yes means no and no means yes. Do you not want to be nonblocking? */
- int nonblocking = 0;
- ioctlsocket(socket, FIONBIO, (unsigned long*) &nonblocking);
- #else
- fcntl(socket, F_SETFL, O_NONBLOCK);
- #endif
- }
- /*
- * Process control
- */
- /* Minimalist interface to run a void function in the background. On
- * unix calls fork, on win32 calls beginthread. Returns -1 on failure.
- * func should not return, but rather should call spawn_exit.
- */
- int spawn_func(int (*func)(void *), void *data)
- {
- #ifdef MS_WINDOWS
- int rv;
- rv = _beginthread(func, 0, data);
- if (rv == (unsigned long) -1)
- return -1;
- return 0;
- #else
- pid_t pid;
- pid = fork();
- if (pid<0)
- return -1;
- if (pid==0) {
- /* Child */
- func(data);
- assert(0); /* Should never reach here. */
- return 0; /* suppress "control-reaches-end-of-non-void" warning. */
- } else {
- /* Parent */
- return 0;
- }
- #endif
- }
- void spawn_exit()
- {
- #ifdef MS_WINDOWS
- _endthread();
- #else
- exit(0);
- #endif
- }
- /*
- * Windows compatibility.
- */
- int
- tor_socketpair(int family, int type, int protocol, int fd[2])
- {
- #ifdef HAVE_SOCKETPAIR_XXXX
- /* For testing purposes, we never fall back to real socketpairs. */
- return socketpair(family, type, protocol, fd);
- #else
- int listener = -1;
- int connector = -1;
- int acceptor = -1;
- struct sockaddr_in listen_addr;
- struct sockaddr_in connect_addr;
- int size;
- if (protocol
- #ifdef AF_UNIX
- || family != AF_UNIX
- #endif
- ) {
- #ifdef MS_WINDOWS
- errno = WSAEAFNOSUPPORT;
- #else
- errno = EAFNOSUPPORT;
- #endif
- return -1;
- }
- if (!fd) {
- errno = EINVAL;
- return -1;
- }
- listener = socket(AF_INET, type, 0);
- if (listener == -1)
- return -1;
- memset (&listen_addr, 0, sizeof (listen_addr));
- listen_addr.sin_family = AF_INET;
- listen_addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
- listen_addr.sin_port = 0; /* kernel choses port. */
- if (bind(listener, (struct sockaddr *) &listen_addr, sizeof (listen_addr))
- == -1)
- goto tidy_up_and_fail;
- if (listen(listener, 1) == -1)
- goto tidy_up_and_fail;
- connector = socket(AF_INET, type, 0);
- if (connector == -1)
- goto tidy_up_and_fail;
- /* We want to find out the port number to connect to. */
- size = sizeof (connect_addr);
- if (getsockname(listener, (struct sockaddr *) &connect_addr, &size) == -1)
- goto tidy_up_and_fail;
- if (size != sizeof (connect_addr))
- goto abort_tidy_up_and_fail;
- if (connect(connector, (struct sockaddr *) &connect_addr,
- sizeof (connect_addr)) == -1)
- goto tidy_up_and_fail;
- size = sizeof (listen_addr);
- acceptor = accept(listener, (struct sockaddr *) &listen_addr, &size);
- if (acceptor == -1)
- goto tidy_up_and_fail;
- if (size != sizeof(listen_addr))
- goto abort_tidy_up_and_fail;
- close(listener);
- /* Now check we are talking to ourself by matching port and host on the
- two sockets. */
- if (getsockname(connector, (struct sockaddr *) &connect_addr, &size) == -1)
- goto tidy_up_and_fail;
- if (size != sizeof (connect_addr)
- || listen_addr.sin_family != connect_addr.sin_family
- || listen_addr.sin_addr.s_addr != connect_addr.sin_addr.s_addr
- || listen_addr.sin_port != connect_addr.sin_port) {
- goto abort_tidy_up_and_fail;
- }
- fd[0] = connector;
- fd[1] = acceptor;
- return 0;
- abort_tidy_up_and_fail:
- #ifdef MS_WINDOWS
- errno = WSAECONNABORTED;
- #else
- errno = ECONNABORTED; /* I hope this is portable and appropriate. */
- #endif
- tidy_up_and_fail:
- {
- int save_errno = errno;
- if (listener != -1)
- close(listener);
- if (connector != -1)
- close(connector);
- if (acceptor != -1)
- close(acceptor);
- errno = save_errno;
- return -1;
- }
- #endif
- }
- #ifdef MS_WINDOWS
- int correct_socket_errno(int s)
- {
- int optval, optvallen=sizeof(optval);
- assert(errno == WSAEWOULDBLOCK);
- if (getsockopt(s, SOL_SOCKET, SO_ERROR, (void*)&optval, &optvallen))
- return errno;
- if (optval)
- return optval;
- return WSAEWOULDBLOCK;
- }
- #endif
- /*
- * Filesystem operations.
- */
- /* Return FN_ERROR if filename can't be read, FN_NOENT if it doesn't
- * exist, FN_FILE if it is a regular file, or FN_DIR if it's a
- * directory. */
- file_status_t file_status(const char *fname)
- {
- struct stat st;
- if (stat(fname, &st)) {
- if (errno == ENOENT) {
- return FN_NOENT;
- }
- return FN_ERROR;
- }
- if (st.st_mode & S_IFDIR)
- return FN_DIR;
- else if (st.st_mode & S_IFREG)
- return FN_FILE;
- else
- return FN_ERROR;
- }
- /* Check whether dirname exists and is private. If yes returns
- 0. Else returns -1. */
- int check_private_dir(const char *dirname, int create)
- {
- int r;
- struct stat st;
- if (stat(dirname, &st)) {
- if (errno != ENOENT) {
- log(LOG_WARN, "Directory %s cannot be read: %s", dirname,
- strerror(errno));
- return -1;
- }
- if (!create) {
- log(LOG_WARN, "Directory %s does not exist.", dirname);
- return -1;
- }
- log(LOG_INFO, "Creating directory %s", dirname);
- #ifdef MS_WINDOWS
- r = mkdir(dirname);
- #else
- r = mkdir(dirname, 0700);
- #endif
- if (r) {
- log(LOG_WARN, "Error creating directory %s: %s", dirname,
- strerror(errno));
- return -1;
- } else {
- return 0;
- }
- }
- if (!(st.st_mode & S_IFDIR)) {
- log(LOG_WARN, "%s is not a directory", dirname);
- return -1;
- }
- #ifndef MS_WINDOWS
- if (st.st_uid != getuid()) {
- log(LOG_WARN, "%s is not owned by this UID (%d)", dirname, (int)getuid());
- return -1;
- }
- if (st.st_mode & 0077) {
- log(LOG_WARN, "Fixing permissions on directory %s", dirname);
- if (chmod(dirname, 0700)) {
- log(LOG_WARN, "Could not chmod directory %s: %s", dirname,
- strerror(errno));
- return -1;
- } else {
- return 0;
- }
- }
- #endif
- return 0;
- }
- int
- write_str_to_file(const char *fname, const char *str)
- {
- char tempname[1024];
- int fd;
- FILE *file;
- if ((strlcpy(tempname,fname,1024) >= 1024) ||
- (strlcat(tempname,".tmp",1024) >= 1024)) {
- log(LOG_WARN, "Filename %s.tmp too long (>1024 chars)", fname);
- return -1;
- }
- if ((fd = open(tempname, O_WRONLY|O_CREAT|O_TRUNC, 0600)) < 0) {
- log(LOG_WARN, "Couldn't open %s for writing: %s", tempname,
- strerror(errno));
- return -1;
- }
- if (!(file = fdopen(fd, "w"))) {
- log(LOG_WARN, "Couldn't fdopen %s for writing: %s", tempname,
- strerror(errno));
- close(fd); return -1;
- }
- if (fputs(str,file) == EOF) {
- log(LOG_WARN, "Error writing to %s: %s", tempname, strerror(errno));
- fclose(file); return -1;
- }
- fclose(file);
- if (rename(tempname, fname)) {
- log(LOG_WARN, "Error replacing %s: %s", fname, strerror(errno));
- return -1;
- }
- return 0;
- }
- char *read_file_to_str(const char *filename) {
- int fd; /* router file */
- struct stat statbuf;
- char *string;
- assert(filename);
- if(strcspn(filename,CONFIG_LEGAL_FILENAME_CHARACTERS) != 0) {
- log_fn(LOG_WARN,"Filename %s contains illegal characters.",filename);
- return NULL;
- }
- if(stat(filename, &statbuf) < 0) {
- log_fn(LOG_INFO,"Could not stat %s.",filename);
- return NULL;
- }
- fd = open(filename,O_RDONLY,0);
- if (fd<0) {
- log_fn(LOG_WARN,"Could not open %s.",filename);
- return NULL;
- }
- string = tor_malloc(statbuf.st_size+1);
- if(read_all(fd,string,statbuf.st_size,0) != statbuf.st_size) {
- log_fn(LOG_WARN,"Couldn't read all %ld bytes of file '%s'.",
- (long)statbuf.st_size,filename);
- free(string);
- close(fd);
- return NULL;
- }
- close(fd);
- string[statbuf.st_size] = 0; /* null terminate it */
- return string;
- }
- /* read lines from f (no more than maxlen-1 bytes each) until we
- * get a non-whitespace line. If it isn't of the form "key value"
- * (value can have spaces), return -1.
- * Point *key to the first word in line, point *value * to the second.
- * Put a \0 at the end of key, remove everything at the end of value
- * that is whitespace or comment.
- * Return 1 if success, 0 if no more lines, -1 if error.
- */
- int parse_line_from_file(char *line, int maxlen, FILE *f, char **key_out, char **value_out) {
- char *s, *key, *end, *value;
- try_next_line:
- if(!fgets(line, maxlen, f)) {
- if(feof(f))
- return 0;
- return -1; /* real error */
- }
- if((s = strchr(line,'#'))) /* strip comments */
- *s = 0; /* stop the line there */
- /* remove end whitespace */
- s = strchr(line, 0); /* now we're at the null */
- do {
- *s = 0;
- s--;
- } while (s >= line && isspace((int)*s));
- key = line;
- while(isspace((int)*key))
- key++;
- if(*key == 0)
- goto try_next_line; /* this line has nothing on it */
- end = key;
- while(*end && !isspace((int)*end))
- end++;
- value = end;
- while(*value && isspace((int)*value))
- value++;
- if(!*end || !*value) { /* only a key on this line. no value. */
- *end = 0;
- log_fn(LOG_WARN,"Line has keyword '%s' but no value. Failing.",key);
- return -1;
- }
- *end = 0; /* null it out */
- log_fn(LOG_DEBUG,"got keyword '%s', value '%s'", key, value);
- *key_out = key, *value_out = value;
- return 1;
- }
- int is_internal_IP(uint32_t ip) {
- if (((ip & 0xff000000) == 0x0a000000) || /* 10/8 */
- ((ip & 0xff000000) == 0x00000000) || /* 0/8 */
- ((ip & 0xff000000) == 0x7f000000) || /* 127/8 */
- ((ip & 0xffff0000) == 0xa9fe0000) || /* 169.254/16 */
- ((ip & 0xfff00000) == 0xac100000) || /* 172.16/12 */
- ((ip & 0xffff0000) == 0xc0a80000)) /* 192.168/16 */
- return 1;
- return 0;
- }
- static char uname_result[256];
- static int uname_result_is_set = 0;
- const char *
- get_uname(void)
- {
- #ifdef HAVE_UNAME
- struct utsname u;
- #endif
- if (!uname_result_is_set) {
- #ifdef HAVE_UNAME
- if (!uname((&u))) {
- snprintf(uname_result, 255, "%s %s %s",
- u.sysname, u.nodename, u.machine);
- uname_result[255] = '\0';
- } else
- #endif
- {
- strcpy(uname_result, "Unknown platform");
- }
- uname_result_is_set = 1;
- }
- return uname_result;
- }
- #ifndef MS_WINDOWS
- /* Based on code contributed by christian grothoff */
- static int start_daemon_called = 0;
- static int finish_daemon_called = 0;
- static int daemon_filedes[2];
- void start_daemon(char *desired_cwd)
- {
- pid_t pid;
- if (start_daemon_called)
- return;
- start_daemon_called = 1;
- if(!desired_cwd)
- desired_cwd = "/";
- /* Don't hold the wrong FS mounted */
- if (chdir(desired_cwd) < 0) {
- log_fn(LOG_ERR,"chdir to %s failed. Exiting.",desired_cwd);
- exit(1);
- }
- pipe(daemon_filedes);
- pid = fork();
- if (pid < 0) {
- log_fn(LOG_ERR,"fork failed. Exiting.");
- exit(1);
- }
- if (pid) { /* Parent */
- int ok;
- char c;
- close(daemon_filedes[1]); /* we only read */
- ok = -1;
- while (0 < read(daemon_filedes[0], &c, sizeof(char))) {
- if (c == '.')
- ok = 1;
- }
- fflush(stdout);
- if (ok == 1)
- exit(0);
- else
- exit(1); /* child reported error */
- } else { /* Child */
- close(daemon_filedes[0]); /* we only write */
- pid = setsid(); /* Detach from controlling terminal */
- /*
- * Fork one more time, so the parent (the session group leader) can exit.
- * This means that we, as a non-session group leader, can never regain a
- * controlling terminal. This part is recommended by Stevens's
- * _Advanced Programming in the Unix Environment_.
- */
- if (fork() != 0) {
- exit(0);
- }
- return;
- }
- }
- void finish_daemon(void)
- {
- int nullfd;
- char c = '.';
- if (finish_daemon_called)
- return;
- if (!start_daemon_called)
- start_daemon(NULL);
- finish_daemon_called = 1;
- nullfd = open("/dev/null",
- O_CREAT | O_RDWR | O_APPEND);
- if (nullfd < 0) {
- log_fn(LOG_ERR,"/dev/null can't be opened. Exiting.");
- exit(1);
- }
- /* close fds linking to invoking terminal, but
- * close usual incoming fds, but redirect them somewhere
- * useful so the fds don't get reallocated elsewhere.
- */
- if (dup2(nullfd,0) < 0 ||
- dup2(nullfd,1) < 0 ||
- dup2(nullfd,2) < 0) {
- log_fn(LOG_ERR,"dup2 failed. Exiting.");
- exit(1);
- }
- write(daemon_filedes[1], &c, sizeof(char)); /* signal success */
- close(daemon_filedes[1]);
- }
- #else
- /* defined(MS_WINDOWS) */
- void start_daemon(char *cp) {}
- void finish_daemon(void) {}
- #endif
- void write_pidfile(char *filename) {
- #ifndef MS_WINDOWS
- FILE *pidfile;
- if ((pidfile = fopen(filename, "w")) == NULL) {
- log_fn(LOG_WARN, "unable to open %s for writing: %s", filename,
- strerror(errno));
- } else {
- fprintf(pidfile, "%d", (int)getpid());
- fclose(pidfile);
- }
- #endif
- }
- int switch_id(char *user, char *group) {
- #ifndef MS_WINDOWS
- struct passwd *pw = NULL;
- struct group *gr = NULL;
- if (user) {
- pw = getpwnam(user);
- if (pw == NULL) {
- log_fn(LOG_ERR,"User '%s' not found.", user);
- return -1;
- }
- }
- /* switch the group first, while we still have the privileges to do so */
- if (group) {
- gr = getgrnam(group);
- if (gr == NULL) {
- log_fn(LOG_ERR,"Group '%s' not found.", group);
- return -1;
- }
- if (setgid(gr->gr_gid) != 0) {
- log_fn(LOG_ERR,"Error setting GID: %s", strerror(errno));
- return -1;
- }
- } else if (user) {
- if (setgid(pw->pw_gid) != 0) {
- log_fn(LOG_ERR,"Error setting GID: %s", strerror(errno));
- return -1;
- }
- }
- /* now that the group is switched, we can switch users and lose
- privileges */
- if (user) {
- if (setuid(pw->pw_uid) != 0) {
- log_fn(LOG_ERR,"Error setting UID: %s", strerror(errno));
- return -1;
- }
- }
- return 0;
- #endif
- log_fn(LOG_ERR,
- "User or group specified, but switching users is not supported.");
- return -1;
- }
- int tor_inet_aton(const char *c, struct in_addr* addr)
- {
- #ifdef HAVE_INET_ATON
- return inet_aton(c, addr);
- #else
- uint32_t r;
- assert(c && addr);
- if (strcmp(c, "255.255.255.255") == 0) {
- addr->s_addr = 0xFFFFFFFFu;
- return 1;
- }
- r = inet_addr(c);
- if (r == INADDR_NONE)
- return 0;
- addr->s_addr = r;
- return 1;
- #endif
- }
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