--- glibc-2.5.orig/sunrpc/bindrsvprt.c +++ glibc-2.5/sunrpc/bindrsvprt.c @@ -30,28 +30,106 @@ * Copyright (c) 1987 by Sun Microsystems, Inc. */ +#include +#include #include +#include #include #include #include #include #include +#define STARTPORT 600 +#define LOWPORT 512 +#define ENDPORT (IPPORT_RESERVED - 1) +#define NPORTS (ENDPORT - STARTPORT + 1) + +/* + * Read the file /etc/bindresvport.blacklist, so that we don't bind + * to this ports. + */ + +static int blacklist_read; +static int *list; +static int list_size = 0; + +static void +load_blacklist (void) +{ + FILE *fp; + char *buf = NULL; + size_t buflen = 0; + int size = 0, ptr = 0; + + blacklist_read = 1; + + fp = fopen ("/etc/bindresvport.blacklist", "r"); + if (NULL == fp) + return; + + while (!feof (fp)) + { + unsigned long port; + char *tmp, *cp; + ssize_t n = __getline (&buf, &buflen, fp); + if (n < 1) + break; + + cp = buf; + tmp = strchr (cp, '#'); /* remove comments */ + if (tmp) + *tmp = '\0'; + while (isspace ((int)*cp)) /* remove spaces and tabs */ + ++cp; + if (*cp == '\0') /* ignore empty lines */ + continue; + if (cp[strlen (cp) - 1] == '\n') + cp[strlen (cp) - 1] = '\0'; + + port = strtoul (cp, &tmp, 0); + if (*tmp != '\0' || (port == ULONG_MAX && errno == ERANGE)) + continue; + + /* Don't bother with out-of-range ports */ + if (port < LOWPORT || port > ENDPORT) + continue; + + if (ptr >= size) + { + size += 10; + list = realloc (list, size * sizeof (int)); + if (list == NULL) + { + free (buf); + return; + } + } + + list[ptr++] = port; + } + + fclose (fp); + + if (buf) + free (buf); + + list_size = ptr; +} + /* * Bind a socket to a privileged IP port */ int bindresvport (int sd, struct sockaddr_in *sin) { + static short startport = STARTPORT; static short port; struct sockaddr_in myaddr; int i; -#define STARTPORT 600 -#define LOWPORT 512 -#define ENDPORT (IPPORT_RESERVED - 1) -#define NPORTS (ENDPORT - STARTPORT + 1) - static short startport = STARTPORT; + if (!blacklist_read) + load_blacklist (); if (sin == (struct sockaddr_in *) 0) { @@ -70,6 +148,7 @@ #define NPORTS (ENDPORT - STARTPORT + 1) port = (__getpid () % NPORTS) + STARTPORT; } + __set_errno (EADDRINUSE); /* Initialize to make gcc happy. */ int res = -1; @@ -78,12 +157,22 @@ #define NPORTS (ENDPORT - STARTPORT + 1) again: for (i = 0; i < nports; ++i) { - sin->sin_port = htons (port++); - if (port > endport) - port = startport; + int j; + + sin->sin_port = htons (port); + + /* Check, if this port is not blacklisted. */ + for (j = 0; j < list_size; j++) + if (port == list[j]) + goto try_next_port; + res = __bind (sd, sin, sizeof (struct sockaddr_in)); if (res >= 0 || errno != EADDRINUSE) break; + +try_next_port: + if (++port > endport) + port = startport; } if (i == nports && startport != LOWPORT)