diff options
Diffstat (limited to 'hacks/glx/sonar-icmp.c')
| -rw-r--r-- | hacks/glx/sonar-icmp.c | 1789 |
1 files changed, 0 insertions, 1789 deletions
diff --git a/hacks/glx/sonar-icmp.c b/hacks/glx/sonar-icmp.c deleted file mode 100644 index b23b6bf..0000000 --- a/hacks/glx/sonar-icmp.c +++ /dev/null @@ -1,1789 +0,0 @@ -/* sonar, Copyright © 1998-2021 Jamie Zawinski and Stephen Martin - * - * Permission to use, copy, modify, distribute, and sell this software and its - * documentation for any purpose is hereby granted without fee, provided that - * the above copyright notice appear in all copies and that both that - * copyright notice and this permission notice appear in supporting - * documentation. No representations are made about the suitability of this - * software for any purpose. It is provided "as is" without express or - * implied warranty. - * - * This implements the "ping" sensor for sonar. - */ - -#include "screenhackI.h" -#include "sonar.h" -#include "version.h" -#include "async_netdb.h" - -#undef usleep /* conflicts with unistd.h on OSX */ - -#ifdef HAVE_IPHONE - /* Note: to get this to compile for iPhone, you need to fix Xcode! - The icmp headers exist for the simulator build environment, but - not for the real-device build environment. This appears to - just be an Apple bug, not intentional. But it has existed for - many years. - - The "ICMP Sanity Check" build phase in the Xcode project checks - this and tells you what to do. - - xc=/Applications/Xcode.app/Contents - for path in /Developer/Platforms/iPhone*?/Developer/SDKs/?* \ - $xc/Developer/Platforms/iPhone*?/Developer/SDKs/?* ; do - for file in \ - /usr/include/netinet/ip.h \ - /usr/include/netinet/in_systm.h \ - /usr/include/netinet/ip_icmp.h \ - /usr/include/netinet/ip_var.h \ - /usr/include/netinet/udp.h - do - ln -s "$file" "$path$file" - done - done - */ -#endif - -#ifndef HAVE_MOBILE -# define READ_FILES -#endif - -#if defined(HAVE_ICMP) || defined(HAVE_ICMPHDR) -# include <unistd.h> -# include <sys/stat.h> -# include <limits.h> -# include <signal.h> -# include <fcntl.h> -# include <sys/types.h> -# include <sys/time.h> -# include <sys/ipc.h> -# ifndef HAVE_ANDROID -# include <sys/shm.h> -# endif -# include <sys/socket.h> -# include <netinet/in_systm.h> -# include <netinet/in.h> -# include <netinet/ip.h> -# include <netinet/ip_icmp.h> -# include <netinet/udp.h> -# include <arpa/inet.h> -# include <netdb.h> -# include <errno.h> -# ifdef HAVE_GETIFADDRS -# include <ifaddrs.h> -# endif -# ifdef HAVE_LIBCAP -# include <sys/capability.h> -# endif -#endif /* HAVE_ICMP || HAVE_ICMPHDR */ - -#if defined(HAVE_ICMP) -# define HAVE_PING -# define ICMP icmp -# define ICMP_TYPE(p) (p)->icmp_type -# define ICMP_CODE(p) (p)->icmp_code -# define ICMP_CHECKSUM(p) (p)->icmp_cksum -# define ICMP_ID(p) (p)->icmp_id -# define ICMP_SEQ(p) (p)->icmp_seq -#elif defined(HAVE_ICMPHDR) -# define HAVE_PING -# define ICMP icmphdr -# define ICMP_TYPE(p) (p)->type -# define ICMP_CODE(p) (p)->code -# define ICMP_CHECKSUM(p) (p)->checksum -# define ICMP_ID(p) (p)->un.echo.id -# define ICMP_SEQ(p) (p)->un.echo.sequence -#else -# undef HAVE_PING -#endif - -#ifndef HAVE_MOBILE -# define LOAD_FILES -#endif - -#ifndef HAVE_PING - -sonar_sensor_data * -sonar_init_ping (Display *dpy, char **error_ret, char **desc_ret, - const char *subnet, int timeout, - Bool resolve_p, Bool times_p, Bool debug_p) -{ - if (! (!subnet || !*subnet || !strcmp(subnet, "default"))) - fprintf (stderr, "%s: not compiled with support for pinging hosts.\n", - progname); - return 0; -} - -#else /* HAVE_PING -- whole file */ - - -#if defined(__DECC) || defined(_IP_VHL) - /* This is how you do it on DEC C, and possibly some BSD systems. */ -# define IP_HDRLEN(ip) ((ip)->ip_vhl & 0x0F) -#else - /* This is how you do it on everything else. */ -# define IP_HDRLEN(ip) ((ip)->ip_hl) -#endif - -/* yes, there is only one, even when multiple savers are running in the - same address space - since we can only open this socket before dropping - privs. - */ -static int global_icmpsock = 0; - -/* Set by a signal handler. */ -static int timer_expired; - - - -static u_short checksum(u_short *, int); -static long delta(struct timeval *, struct timeval *); - - -typedef struct { - Display *dpy; /* Only used to get *useThreads. */ - - char *version; /* short version number of xscreensaver */ - int icmpsock; /* socket for sending pings */ - int pid; /* our process ID */ - int seq; /* packet sequence number */ - int timeout; /* packet timeout */ - - int target_count; - sonar_bogie *targets; /* the hosts we will ping; - those that pong end up on ssd->pending. */ - sonar_bogie *last_pinged; /* pointer into 'targets' list */ - double last_ping_time; - - Bool resolve_p; - Bool times_p; - Bool debug_p; - -} ping_data; - -typedef struct { - async_name_from_addr_t lookup_name; - async_addr_from_name_t lookup_addr; - async_netdb_sockaddr_storage_t address; /* ip address */ - socklen_t addrlen; - char *fallback; -} ping_bogie; - - - -/* Packs an IP address quad into bigendian network order. */ -static in_addr_t -pack_addr (unsigned int a, unsigned int b, unsigned int c, unsigned int d) -{ - unsigned long i = (((a & 255) << 24) | - ((b & 255) << 16) | - ((c & 255) << 8) | - ((d & 255) )); - return htonl (i); -} - -/* Unpacks an IP address quad from bigendian network order. */ -static void -unpack_addr (unsigned long addr, - unsigned int *a, unsigned int *b, - unsigned int *c, unsigned int *d) -{ - addr = ntohl (addr); - *a = (addr >> 24) & 255; - *b = (addr >> 16) & 255; - *c = (addr >> 8) & 255; - *d = (addr ) & 255; -} - - - - -/* Resolves the bogie's name (either a hostname or ip address string) - to a hostent. Returns 1 if successful, 0 if something went wrong. - */ -static int -resolve_bogie_hostname (ping_data *pd, sonar_bogie *sb, Bool resolve_p) -{ - ping_bogie *pb = (ping_bogie *) sb->closure; - - unsigned int ip[4]; - char c; - - if (4 == sscanf (sb->name, " %u.%u.%u.%u %c", - &ip[0], &ip[1], &ip[2], &ip[3], &c)) - { - /* It's an IP address. - */ - struct sockaddr_in *iaddr = (struct sockaddr_in *) &(pb->address); - - if (ip[3] == 0) - { - if (pd->debug_p > 1) - fprintf (stderr, "%s: ignoring bogus IP %s\n", - progname, sb->name); - return 0; - } - - iaddr->sin_family = AF_INET; - iaddr->sin_addr.s_addr = pack_addr (ip[0], ip[1], ip[2], ip[3]); - pb->addrlen = sizeof(struct sockaddr_in); - - if (resolve_p) - { - pb->lookup_name = - async_name_from_addr_start (pd->dpy, - (const struct sockaddr *)&pb->address, - pb->addrlen); - if (!pb->lookup_name) - { - fprintf (stderr, "%s: unable to start host resolution.\n", - progname); - } - } - } - else - { - /* It's a host name. */ - - /* don't waste time being confused by non-hostname tokens - in .ssh/known_hosts */ - if (!strcmp (sb->name, "ssh-rsa") || - !strcmp (sb->name, "ssh-dsa") || - !strcmp (sb->name, "ssh-dss") || - !strncmp (sb->name, "ecdsa-", 6) || - strlen (sb->name) >= 80) - return 0; - - /* .ssh/known_hosts sometimes contains weirdness like "[host]:port". - Ignore it. */ - if (strchr (sb->name, '[')) - { - if (pd->debug_p) - fprintf (stderr, "%s: ignoring bogus address \"%s\"\n", - progname, sb->name); - return 0; - } - - /* If the name contains a colon, it's probably IPv6. */ - if (strchr (sb->name, ':')) - { - if (pd->debug_p) - fprintf (stderr, "%s: ignoring ipv6 address \"%s\"\n", - progname, sb->name); - return 0; - } - - pb->lookup_addr = async_addr_from_name_start(pd->dpy, sb->name); - if (!pb->lookup_addr) - { - if (pd->debug_p) - /* Either address space exhaustion or RAM exhaustion. */ - fprintf (stderr, "%s: unable to start host resolution.\n", - progname); - return 0; - } - } - return 1; -} - - -static void -print_address (FILE *out, int width, const void *sockaddr, socklen_t addrlen) -{ -#ifdef HAVE_GETADDRINFO - char buf[NI_MAXHOST]; -#else - char buf[50]; -#endif - - const struct sockaddr *addr = (const struct sockaddr *)sockaddr; - const char *ips = buf; - - if (!addr->sa_family) - ips = "<no address>"; - else - { -#ifdef HAVE_GETADDRINFO - int gai_error = getnameinfo (sockaddr, addrlen, buf, sizeof(buf), - NULL, 0, NI_NUMERICHOST); - if (gai_error == EAI_SYSTEM) - ips = strerror(errno); - else if (gai_error) - ips = gai_strerror(gai_error); -#else - switch (addr->sa_family) - { - case AF_INET: - { - u_long ip = ((struct sockaddr_in *)sockaddr)->sin_addr.s_addr; - unsigned int a, b, c, d; - unpack_addr (ip, &a, &b, &c, &d); /* ip is in network order */ - sprintf (buf, "%u.%u.%u.%u", a, b, c, d); - } - break; - default: - ips = "<unknown>"; - break; - } -#endif - } - - fprintf (out, "%-*s", width, ips); -} - - -static void -print_host (FILE *out, const sonar_bogie *sb) -{ - const ping_bogie *pb = (const ping_bogie *) sb->closure; - const char *name = sb->name; - if (!name || !*name) name = "<unknown>"; - print_address (out, 16, &pb->address, pb->addrlen); - fprintf (out, " %s\n", name); -} - - -static Bool -is_address_ok(Bool debug_p, const sonar_bogie *b) -{ - const ping_bogie *pb = (const ping_bogie *) b->closure; - const struct sockaddr *addr = (const struct sockaddr *)&pb->address; - - switch (addr->sa_family) - { - case AF_INET: - { - struct sockaddr_in *iaddr = (struct sockaddr_in *) addr; - - /* Don't ever use loopback (127.0.0.x) hosts */ - unsigned long ip = iaddr->sin_addr.s_addr; - if ((ntohl (ip) & 0xFFFFFF00L) == 0x7f000000L) /* 127.0.0.x */ - { - if (debug_p) - fprintf (stderr, "%s: ignoring loopback host %s\n", - progname, b->name); - return False; - } - - /* Don't ever use broadcast (255.x.x.x) hosts */ - if ((ntohl (ip) & 0xFF000000L) == 0xFF000000L) /* 255.x.x.x */ - { - if (debug_p) - fprintf (stderr, "%s: ignoring broadcast host %s\n", - progname, b->name); - return False; - } - } - - break; - } - - return True; -} - - -/* Create a sonar_bogie from a host name or ip address string. - Returns NULL if the name could not be resolved. - */ -static sonar_bogie * -bogie_for_host (sonar_sensor_data *ssd, const char *name, const char *fallback) -{ - ping_data *pd = (ping_data *) ssd->closure; - sonar_bogie *b = (sonar_bogie *) calloc (1, sizeof(*b)); - ping_bogie *pb = (ping_bogie *) calloc (1, sizeof(*pb)); - Bool resolve_p = pd->resolve_p; - - b->name = strdup (name); - b->closure = pb; - - if (! resolve_bogie_hostname (pd, b, resolve_p)) - goto FAIL; - - if (! pb->lookup_addr && ! is_address_ok (pd->debug_p, b)) - goto FAIL; - - if (pd->debug_p > 1) - { - fprintf (stderr, "%s: added ", progname); - print_host (stderr, b); - } - - if (fallback) - pb->fallback = strdup (fallback); - return b; - - FAIL: - if (b) sonar_free_bogie (ssd, b); - - if (fallback) - return bogie_for_host (ssd, fallback, NULL); - - return 0; -} - - -#ifdef READ_FILES - -/* Return a list of bogies read from a file. - The file can be like /etc/hosts or .ssh/known_hosts or probably - just about anything that has host names in it. - */ -static sonar_bogie * -read_hosts_file (sonar_sensor_data *ssd, const char *filename) -{ - ping_data *pd = (ping_data *) ssd->closure; - FILE *fp; - char buf[LINE_MAX]; - char *p; - sonar_bogie *list = 0; - char *addr, *name; - sonar_bogie *new; - - /* Kludge: on OSX, variables have not been expanded in the command - line arguments, so as a special case, allow the string to begin - with literal "$HOME/" or "~/". - - This is so that the "Known Hosts" menu item in sonar.xml works. - */ - if (!strncmp(filename, "~/", 2) || !strncmp(filename, "$HOME/", 6)) - { - char *s = strchr (filename, '/'); - strcpy (buf, getenv("HOME")); - strcat (buf, s); - filename = buf; - } - - fp = fopen(filename, "r"); - if (!fp) - { -#ifdef HAVE_JWXYZ - if (pd->debug_p) /* on OSX don't syslog this */ -#endif - { - char *str_error = strerror(errno); - fprintf(stderr, "%s: %s: %s", progname, filename, str_error); - } - return 0; - } - - if (pd->debug_p) - fprintf (stderr, "%s: reading \"%s\"\n", progname, filename); - - while ((p = fgets(buf, LINE_MAX, fp))) - { - while ((*p == ' ') || (*p == '\t')) /* skip whitespace */ - p++; - if (*p == '#') /* skip comments */ - continue; - - /* Get the name and address */ - - if ((addr = strtok(buf, " ,;\t\n"))) - name = strtok(0, " ,;\t\n"); - else - continue; - - /* Check to see if the addr looks like an addr. If not, assume - the addr is a name and there is no addr. This way, we can - handle files whose lines have "xx.xx.xx.xx hostname" as their - first two tokens, and also files that have a hostname as their - first token (like .ssh/known_hosts and .rhosts.) - */ - { - int i; char c; - if (4 != sscanf(addr, "%d.%d.%d.%d%c", &i, &i, &i, &i, &c)) - { - name = addr; - addr = 0; - } - } - - /* If the name is all digits, it's not a name. */ - if (name) - { - const char *s; - for (s = name; *s; s++) - if (*s < '0' || *s > '9') - break; - if (! *s) - { - if (pd->debug_p > 1) - fprintf (stderr, "%s: skipping bogus name \"%s\" (%s)\n", - progname, name, addr); - name = 0; - } - } - - /* Create a new target using first the name then the address */ - - if (!name) - { - name = addr; - addr = NULL; - } - - new = bogie_for_host (ssd, name, addr); - - if (new) - { - new->next = list; - list = new; - } - } - - fclose(fp); - return list; -} -#endif /* READ_FILES */ - - -static sonar_bogie ** -found_duplicate_host (const ping_data *pd, sonar_bogie **list, - sonar_bogie *bogie) -{ - if (pd->debug_p) - { - fprintf (stderr, "%s: deleted duplicate: ", progname); - print_host (stderr, bogie); - } - - return list; -} - - -static sonar_bogie ** -find_duplicate_host (const ping_data *pd, sonar_bogie **list, - sonar_bogie *bogie) -{ - const ping_bogie *pb = (const ping_bogie *) bogie->closure; - const struct sockaddr *addr1 = (const struct sockaddr *) &(pb->address); - - while(*list) - { - const ping_bogie *pb2 = (const ping_bogie *) (*list)->closure; - - if (!pb2->lookup_addr) - { - const struct sockaddr *addr2 = - (const struct sockaddr *) &(pb2->address); - - if (addr1->sa_family == addr2->sa_family) - { - switch (addr1->sa_family) - { - case AF_INET: - { - unsigned long ip1 = - ((const struct sockaddr_in *)addr1)->sin_addr.s_addr; - const struct sockaddr_in *i2 = - (const struct sockaddr_in *)addr2; - unsigned long ip2 = i2->sin_addr.s_addr; - - if (ip1 == ip2) - return found_duplicate_host (pd, list, bogie); - } - break; -#ifdef AF_INET6 - case AF_INET6: - { - if (! memcmp( - &((const struct sockaddr_in6 *)addr1)->sin6_addr, - &((const struct sockaddr_in6 *)addr2)->sin6_addr, - 16)) - return found_duplicate_host (pd, list, bogie); - } - break; -#endif - default: - { - /* Fallback behavior: Just memcmp the two addresses. - - For this to work, unused space in the sockaddr must be - set to zero. Which may actually be the case: - - async_addr_from_name_finish won't put garbage into - sockaddr_in.sin_zero or elsewhere unless getaddrinfo - does. - - ping_bogie is allocated with calloc(). */ - - if (pb->addrlen == pb2->addrlen && - ! memcmp(addr1, addr2, pb->addrlen)) - return found_duplicate_host (pd, list, bogie); - } - break; - } - } - } - - list = &(*list)->next; - } - - return NULL; -} - - -static sonar_bogie * -delete_duplicate_hosts (sonar_sensor_data *ssd, sonar_bogie *list) -{ - ping_data *pd = (ping_data *) ssd->closure; - sonar_bogie *head = list; - sonar_bogie *sb = head; - - while (sb) - { - ping_bogie *pb = (ping_bogie *) sb->closure; - - if (!pb->lookup_addr) - { - sonar_bogie **sb2 = find_duplicate_host (pd, &sb->next, sb); - if (sb2) - *sb2 = (*sb2)->next; - /* #### sb leaked */ - else - sb = sb->next; - } - else - sb = sb->next; - } - - return head; -} - - -static unsigned long -width_mask (unsigned long width) -{ - unsigned long m = 0; - int i; - for (i = 0; i < width; i++) - m |= (1L << (31-i)); - return m; -} - - -#ifdef HAVE_GETIFADDRS -static unsigned int -mask_width (unsigned long mask) -{ - int i; - for (i = 0; i < 32; i++) - if (mask & (1 << i)) - break; - return 32-i; -} -#endif - - -/* Generate a list of bogies consisting of all of the entries on - the same subnet. 'base' ip is in network order; 0 means localhost. - */ -static sonar_bogie * -subnet_hosts (sonar_sensor_data *ssd, char **error_ret, char **desc_ret, - unsigned long n_base, int subnet_width) -{ - ping_data *pd = (ping_data *) ssd->closure; - unsigned long h_mask; /* host order */ - unsigned long h_base; /* host order */ - char address[BUFSIZ]; - char *p; - int i; - sonar_bogie *new; - sonar_bogie *list = 0; - char buf[1024]; - - if (subnet_width < 24) - { - sprintf (buf, - "Pinging %lu hosts is a bad\n" - "idea. Please use a subnet\n" - "mask of 24 bits or more.", - (unsigned long) (1L << (32 - subnet_width)) - 1); - *error_ret = strdup(buf); - return 0; - } - else if (subnet_width > 30) - { - sprintf (buf, - "An %d-bit subnet\n" - "doesn't make sense.\n" - "Try \"subnet/24\"\n" - "or \"subnet/29\".\n", - subnet_width); - *error_ret = strdup(buf); - return 0; - } - - - if (pd->debug_p) - fprintf (stderr, "%s: adding %d-bit subnet\n", progname, subnet_width); - - - if (! n_base) - { -# ifdef HAVE_GETIFADDRS - - /* To determine the local subnet, we need to know the local IP address. - Do this by looking at the IPs of every network interface. - */ - struct in_addr in = { 0, }; - struct ifaddrs *all = 0, *ifa; - - if (pd->debug_p) - fprintf (stderr, "%s: listing network interfaces\n", progname); - - getifaddrs (&all); - for (ifa = all; ifa; ifa = ifa->ifa_next) - { - struct in_addr in2; - unsigned long mask; - if (! ifa->ifa_addr) - continue; - else if (ifa->ifa_addr->sa_family != AF_INET) - { - if (pd->debug_p) - fprintf (stderr, "%s: if: %4s: %s\n", progname, - ifa->ifa_name, - ( -# ifdef AF_UNIX - ifa->ifa_addr->sa_family == AF_UNIX ? "local" : -# endif -# ifdef AF_LINK - ifa->ifa_addr->sa_family == AF_LINK ? "link" : -# endif -# ifdef AF_INET6 - ifa->ifa_addr->sa_family == AF_INET6 ? "ipv6" : -# endif - "other")); - continue; - } - in2 = ((struct sockaddr_in *) ifa->ifa_addr)->sin_addr; - mask = ntohl (((struct sockaddr_in *) ifa->ifa_netmask) - ->sin_addr.s_addr); - if (pd->debug_p) - fprintf (stderr, "%s: if: %4s: inet = %s /%d 0x%08lx\n", - progname, - ifa->ifa_name, - inet_ntoa (in2), - mask_width (mask), - mask); - if (in2.s_addr == 0x0100007f || /* 127.0.0.1 in network order */ - ((in2.s_addr & 0x000000ff) == 0x7f) || /* 127.0.0.0/24 */ - mask == 0) - /* Assume all 127 addresses are loopback, not just 127.0.0.1. */ - continue; - - /* At least on the AT&T 3G network, pinging either of the two - hosts on a /31 network doesn't work, so don't try. - */ - if (mask_width (mask) == 31) - { - sprintf (buf, - "Can't ping subnet:\n" - "local network is\n" - "%.100s/%d,\n" - "a p2p bridge\n" - "on if %.100s.", - inet_ntoa (in2), mask_width (mask), ifa->ifa_name); - if (*error_ret) free (*error_ret); - *error_ret = strdup (buf); - continue; - } - - in = in2; - subnet_width = mask_width (mask); - - /* Take the first non-loopback network: prefer en0 over en1. */ - if (in.s_addr && subnet_width) - break; - } - - if (in.s_addr) - { - if (*error_ret) free (*error_ret); - *error_ret = 0; - n_base = in.s_addr; /* already in network order, I think? */ - } - else if (!*error_ret) - *error_ret = strdup ("Unable to determine\nlocal IP address\n"); - - if (all) - freeifaddrs (all); - - if (*error_ret) - return 0; - -# else /* !HAVE_GETIFADDRS */ - - /* If we can't walk the list of network interfaces to figure out - our local IP address, try to do it by finding the local host - name, then resolving that. - */ - char hostname[BUFSIZ]; - struct hostent *hent = 0; - - if (gethostname(hostname, BUFSIZ)) - { - *error_ret = strdup ("Unable to determine\n" - "local host name!"); - return 0; - } - - /* Get our IP address and convert it to a string */ - - hent = gethostbyname(hostname); - if (! hent) - { - strcat (hostname, ".local"); /* Necessary on iphone */ - hent = gethostbyname(hostname); - } - - if (! hent) - { - sprintf(buf, - "Unable to resolve\n" - "local host \"%.100s\"", - hostname); - *error_ret = strdup(buf); - return 0; - } - - strcpy (address, inet_ntoa(*((struct in_addr *)hent->h_addr_list[0]))); - n_base = pack_addr (hent->h_addr_list[0][0], - hent->h_addr_list[0][1], - hent->h_addr_list[0][2], - hent->h_addr_list[0][3]); - - if (n_base == 0x0100007f) /* 127.0.0.1 in network order */ - { - unsigned int a, b, c, d; - unpack_addr (n_base, &a, &b, &c, &d); - sprintf (buf, - "Unable to determine\n" - "local subnet address:\n" - "\"%.100s\"\n" - "resolves to\n" - "loopback address\n" - "%u.%u.%u.%u.", - hostname, a, b, c, d); - *error_ret = strdup(buf); - return 0; - } - -# endif /* !HAVE_GETIFADDRS */ - } - - - /* Construct targets for all addresses in this subnet */ - - h_mask = width_mask (subnet_width); - h_base = ntohl (n_base); - - if (desc_ret && !*desc_ret) { - char buf2[255]; - unsigned int a, b, c, d; - unsigned long bb = n_base & htonl(h_mask); - unpack_addr (bb, &a, &b, &c, &d); - if (subnet_width > 24) - sprintf (buf2, "%u.%u.%u.%u/%d", a, b, c, d, subnet_width); - else - sprintf (buf2, "%u.%u.%u/%d", a, b, c, subnet_width); - *desc_ret = strdup (buf2); - } - - for (i = 255; i >= 0; i--) { - unsigned int a, b, c, d; - int ip = (h_base & 0xFFFFFF00L) | i; /* host order */ - - if ((ip & h_mask) != (h_base & h_mask)) /* skip out-of-subnet host */ - continue; - else if (subnet_width == 31) /* 1-bit bridge: 2 hosts */ - ; - else if ((ip & ~h_mask) == 0) /* skip network address */ - continue; - else if ((ip & ~h_mask) == ~h_mask) /* skip broadcast address */ - continue; - - unpack_addr (htonl (ip), &a, &b, &c, &d); - sprintf (address, "%u.%u.%u.%u", a, b, c, d); - - if (pd->debug_p > 1) - { - unsigned int aa, ab, ac, ad; - unsigned int ma, mb, mc, md; - unpack_addr (htonl (h_base & h_mask), &aa, &ab, &ac, &ad); - unpack_addr (htonl (h_mask), &ma, &mb, &mc, &md); - fprintf (stderr, - "%s: subnet: %s (%u.%u.%u.%u & %u.%u.%u.%u / %d)\n", - progname, address, - aa, ab, ac, ad, - ma, mb, mc, md, - subnet_width); - } - - p = address + strlen(address) + 1; - sprintf(p, "%d", i); - - new = bogie_for_host (ssd, address, NULL); - if (new) - { - new->next = list; - list = new; - } - } - - return list; -} - - -/* Send a ping packet. - */ -static void -send_ping (ping_data *pd, const sonar_bogie *b) -{ - ping_bogie *pb = (ping_bogie *) b->closure; - u_char *packet; - struct ICMP *icmph; - const char *token = "org.jwz.xscreensaver.sonar"; - char *host_id; - struct timeval tval; - - unsigned long pcktsiz = (sizeof(struct ICMP) + sizeof(struct timeval) + - sizeof(socklen_t) + pb->addrlen + - strlen(token) + 1 + - strlen(pd->version) + 1); - - /* Create the ICMP packet */ - - if (! (packet = (u_char *) calloc(1, pcktsiz))) - return; /* Out of memory */ - - icmph = (struct ICMP *) packet; - ICMP_TYPE(icmph) = ICMP_ECHO; - ICMP_CODE(icmph) = 0; - ICMP_CHECKSUM(icmph) = 0; - ICMP_ID(icmph) = pd->pid; - ICMP_SEQ(icmph) = pd->seq++; - /* struct timeval needs alignment, so we first use aligned buffer for - gettimeofday() and later copy the result to packet buffer - */ -# ifdef GETTIMEOFDAY_TWO_ARGS - gettimeofday((struct timeval *) &tval, - (struct timezone *) 0); -# else - gettimeofday((struct timeval *) &tval); -# endif - memcpy(&packet[sizeof(struct ICMP)], &tval, sizeof tval); - - /* We store the sockaddr of the host we're pinging in the packet, and parse - that out of the return packet later (see get_ping() for why). - After that, we also include the name and version of this program, - just to give a clue to anyone sniffing and wondering what's up. - */ - host_id = (char *) &packet[sizeof(struct ICMP) + sizeof(struct timeval)]; - *(socklen_t *)host_id = pb->addrlen; - host_id += sizeof(socklen_t); - memcpy(host_id, &pb->address, pb->addrlen); - host_id += pb->addrlen; - sprintf (host_id, "%.20s %.20s", token, pd->version); - - ICMP_CHECKSUM(icmph) = checksum((u_short *)packet, pcktsiz); - - /* Send it */ - - if (sendto(pd->icmpsock, packet, pcktsiz, 0, - (struct sockaddr *)&pb->address, sizeof(pb->address)) - != pcktsiz) - { -#if 0 - char buf[BUFSIZ]; - sprintf(buf, "%s: pinging %.100s", progname, b->name); - perror(buf); -#endif - } - - free (packet); -} - -/* signal handler */ -static void -sigcatcher (int sig) -{ - timer_expired = 1; -} - - -/* Compute the checksum on a ping packet. - */ -static u_short -checksum (u_short *packet, int size) -{ - register int nleft = size; - register u_short *w = packet; - register int sum = 0; - u_short answer = 0; - - /* Using a 32 bit accumulator (sum), we add sequential 16 bit words - to it, and at the end, fold back all the carry bits from the - top 16 bits into the lower 16 bits. - */ - while (nleft > 1) - { - sum += *w++; - nleft -= 2; - } - - /* mop up an odd byte, if necessary */ - - if (nleft == 1) - { - *(u_char *)(&answer) = *(u_char *)w ; - *(1 + (u_char *)(&answer)) = 0; - sum += answer; - } - - /* add back carry outs from top 16 bits to low 16 bits */ - - sum = (sum >> 16) + (sum & 0xffff); /* add hi 16 to low 16 */ - sum += (sum >> 16); /* add carry */ - answer = ~sum; /* truncate to 16 bits */ - - return(answer); -} - - -/* Copies the sonar_bogie and the underlying ping_bogie. - */ -static sonar_bogie * -copy_ping_bogie (sonar_sensor_data *ssd, const sonar_bogie *b) -{ - sonar_bogie *b2 = sonar_copy_bogie (ssd, b); - if (b->closure) - { - ping_bogie *pb = (ping_bogie *) b->closure; - ping_bogie *pb2 = (ping_bogie *) calloc (1, sizeof(*pb)); - pb2->address = pb->address; - b2->closure = pb2; - } - return b2; -} - - -/* Look for all outstanding ping replies. - */ -static sonar_bogie * -get_ping (sonar_sensor_data *ssd) -{ - ping_data *pd = (ping_data *) ssd->closure; - struct sockaddr from; - socklen_t fromlen; - int result; - u_char packet[1024]; - struct timeval now; - struct timeval then; - struct ip *ip; - int iphdrlen; - struct ICMP *icmph; - sonar_bogie *bl = 0; - sonar_bogie *new = 0; - struct sigaction sa; - struct itimerval it; - fd_set rfds; - struct timeval tv; - - /* Set up a signal to interrupt our wait for a packet */ - - sigemptyset(&sa.sa_mask); - sa.sa_flags = 0; - sa.sa_handler = sigcatcher; - if (sigaction(SIGALRM, &sa, 0) == -1) - { - char msg[1024]; - sprintf(msg, "%s: unable to trap SIGALRM", progname); - perror(msg); - exit(1); - } - - /* Set up a timer to interupt us if we don't get a packet */ - - it.it_interval.tv_sec = 0; - it.it_interval.tv_usec = 0; - it.it_value.tv_sec = 0; - it.it_value.tv_usec = pd->timeout; - timer_expired = 0; - setitimer(ITIMER_REAL, &it, 0); - - /* Wait for a result packet */ - - fromlen = sizeof(from); - while (! timer_expired) - { - tv.tv_usec = pd->timeout; - tv.tv_sec = 0; -#if 0 - /* This breaks on BSD, which uses bzero() in the definition of FD_ZERO */ - FD_ZERO(&rfds); -#else - memset (&rfds, 0, sizeof(rfds)); -#endif - FD_SET(pd->icmpsock, &rfds); - /* only wait a little while, in case we raced with the timer expiration. - From Valentijn Sessink <valentyn@openoffice.nl> */ - if (select(pd->icmpsock + 1, &rfds, 0, 0, &tv) >0) - { - result = (int)recvfrom (pd->icmpsock, packet, sizeof(packet), - 0, &from, &fromlen); - - /* Check the packet */ - -# ifdef GETTIMEOFDAY_TWO_ARGS - gettimeofday(&now, (struct timezone *) 0); -# else - gettimeofday(&now); -# endif - ip = (struct ip *) packet; - iphdrlen = IP_HDRLEN(ip) << 2; - icmph = (struct ICMP *) &packet[iphdrlen]; - /* struct timeval data in packet is not aligned, move the data to - the aligned buffer - */ - memcpy(&then, &packet[iphdrlen + sizeof(struct ICMP)], sizeof then); - - - /* Ignore anything but ICMP Replies */ - if (ICMP_TYPE(icmph) != ICMP_ECHOREPLY) - continue; - - /* Ignore packets not set from us */ - if (ICMP_ID(icmph) != pd->pid) - continue; - - /* Find the bogie in 'targets' that corresponds to this packet - and copy it, so that this bogie stays in the same spot (th) - on the screen, and so that we don't have to resolve it again. - - We could find the bogie by comparing ip->ip_src.s_addr to - pb->address, but it is possible that, in certain weird router - or NAT situations, that the reply will come back from a - different address than the one we sent it to. So instead, - we parse the sockaddr out of the reply packet payload. - */ - { - const socklen_t *host_id = (socklen_t *) &packet[ - iphdrlen + sizeof(struct ICMP) + sizeof(struct timeval)]; - - sonar_bogie *b; - - /* Ensure that a maliciously-crafted return packet can't - make us overflow in memcmp. */ - if (result > 0 && (const u_char *)(host_id + 1) <= packet + result) - { - const u_char *host_end = (const u_char *)(host_id + 1) + - *host_id; - - if ((const u_char *)(host_id + 1) <= host_end && - host_end <= packet + result) - { - for (b = pd->targets; b; b = b->next) - { - ping_bogie *pb = (ping_bogie *)b->closure; - if (*host_id == pb->addrlen && - !memcmp(&pb->address, host_id + 1, pb->addrlen) ) - { - /* Check to see if the name lookup is done. */ - if (pb->lookup_name && - async_name_from_addr_is_done (pb->lookup_name)) - { - char *host = NULL; - - async_name_from_addr_finish (pb->lookup_name, - &host, NULL); - - if (pd->debug_p > 1) - fprintf (stderr, "%s: %s => %s\n", - progname, b->name, - host ? host : "<unknown>"); - - if (host) - { - free(b->name); - b->name = host; - } - - pb->lookup_name = NULL; - } - - new = copy_ping_bogie (ssd, b); - break; - } - } - } - } - } - - if (! new) /* not in targets? */ - { - unsigned int a, b, c, d; - unpack_addr (ip->ip_src.s_addr, &a, &b, &c, &d); - fprintf (stderr, - "%s: UNEXPECTED PING REPLY! " - "%4d bytes, icmp_seq=%-4d from %d.%d.%d.%d\n", - progname, result, ICMP_SEQ(icmph), a, b, c, d); - continue; - } - - new->next = bl; - bl = new; - - { - double msec = delta(&then, &now) / 1000.0; - - if (pd->times_p) - { - if (new->desc) free (new->desc); - new->desc = (char *) malloc (30); - if (msec > 99) sprintf (new->desc, "%.0f ms", msec); - else if (msec > 9) sprintf (new->desc, "%.1f ms", msec); - else if (msec > 1) sprintf (new->desc, "%.2f ms", msec); - else sprintf (new->desc, "%.3f ms", msec); - } - - if (pd->debug_p && pd->times_p) /* ping-like stdout log */ - { - char *s = strdup(new->name); - char *s2 = s; - if (strlen(s) > 28) - { - s2 = s + strlen(s) - 28; - memcpy (s2, "...", 3); - } - fprintf (stdout, - "%3d bytes from %28s: icmp_seq=%-4d time=%s\n", - result, s2, ICMP_SEQ(icmph), new->desc); - fflush (stdout); - free(s); - } - - /* The radius must be between 0.0 and 1.0. - We want to display ping times on a logarithmic scale, - with the three rings being 2.5, 70 and 2,000 milliseconds. - */ - if (msec <= 0) msec = 0.001; - new->r = log (msec * 10) / log (20000); - - /* Don't put anyone *too* close to the center of the screen. */ - if (new->r < 0) new->r = 0; - if (new->r < 0.1) new->r += 0.1; - } - } - } - - return bl; -} - - -/* difference between the two times in microseconds. - */ -static long -delta (struct timeval *then, struct timeval *now) -{ - return (((now->tv_sec - then->tv_sec) * 1000000) + - (now->tv_usec - then->tv_usec)); -} - - -static void -ping_free_data (sonar_sensor_data *ssd, void *closure) -{ - ping_data *pd = (ping_data *) closure; - sonar_bogie *b = pd->targets; - while (b) - { - sonar_bogie *b2 = b->next; - sonar_free_bogie (ssd, b); - b = b2; - } - free (pd); -} - -static void -ping_free_bogie_data (sonar_sensor_data *sd, void *closure) -{ - ping_bogie *pb = (ping_bogie *) closure; - - if (pb->lookup_name) - async_name_from_addr_cancel (pb->lookup_name); - if (pb->lookup_addr) - async_addr_from_name_cancel (pb->lookup_addr); - free (pb->fallback); - - free (closure); -} - - -/* Returns the current time in seconds as a double. - */ -static double -double_time (void) -{ - struct timeval now; -# ifdef GETTIMEOFDAY_TWO_ARGS - struct timezone tzp; - gettimeofday(&now, &tzp); -# else - gettimeofday(&now); -# endif - - return (now.tv_sec + ((double) now.tv_usec * 0.000001)); -} - - -static void -free_bogie_after_lookup(sonar_sensor_data *ssd, sonar_bogie **sbp, - sonar_bogie **sb) -{ - ping_bogie *pb = (ping_bogie *)(*sb)->closure; - - *sbp = (*sb)->next; - pb->lookup_addr = NULL; /* Prevent double-free in sonar_free_bogie. */ - sonar_free_bogie (ssd, *sb); - *sb = NULL; -} - - -/* Pings the next bogie, if it's time. - Returns all outstanding ping replies. - */ -static sonar_bogie * -ping_scan (sonar_sensor_data *ssd) -{ - ping_data *pd = (ping_data *) ssd->closure; - double now = double_time(); - double ping_cycle = 10; /* re-ping a given host every 10 seconds */ - double ping_interval = ping_cycle / pd->target_count; - - if (now > pd->last_ping_time + ping_interval) /* time to ping someone */ - { - struct sonar_bogie **sbp; - - if (pd->last_pinged) - { - sbp = &pd->last_pinged->next; - if (!*sbp) - sbp = &pd->targets; - } - else - sbp = &pd->targets; - - if (!*sbp) - /* Aaaaand we're out of bogies. */ - pd->last_pinged = NULL; - else - { - sonar_bogie *sb = *sbp; - ping_bogie *pb = (ping_bogie *)sb->closure; - if (pb->lookup_addr && - async_addr_from_name_is_done (pb->lookup_addr)) - { - if (async_addr_from_name_finish (pb->lookup_addr, &pb->address, - &pb->addrlen, NULL)) - { - char *fallback = pb->fallback; - pb->fallback = NULL; - - if (pd->debug_p) - fprintf (stderr, "%s: could not resolve host: %s\n", - progname, sb->name); - - free_bogie_after_lookup (ssd, sbp, &sb); - - /* Insert the fallback bogie right where the old one was. */ - if (fallback) - { - sonar_bogie *new_bogie = bogie_for_host (ssd, fallback, - NULL); - if (new_bogie) { - new_bogie->next = *sbp; - - if (! ((ping_bogie *)new_bogie->closure)->lookup_addr && - ! find_duplicate_host(pd, &pd->targets, new_bogie)) - *sbp = new_bogie; - else - sonar_free_bogie (ssd, new_bogie); - } - - free (fallback); - } - } - else - { - if (pd->debug_p > 1) - { - fprintf (stderr, "%s: %s => ", progname, sb->name); - print_address (stderr, 0, &pb->address, pb->addrlen); - putc('\n', stderr); - } - - if (! is_address_ok (pd->debug_p, sb)) - free_bogie_after_lookup (ssd, sbp, &sb); - else if (find_duplicate_host (pd, &pd->targets, sb)) - /* Tricky: find_duplicate_host skips the current bogie when - scanning the targets list because pb->lookup_addr hasn't - been NULL'd yet. - - Not that it matters much, but behavior here is to - keep the existing address. - */ - free_bogie_after_lookup (ssd, sbp, &sb); - } - - if (sb) - pb->lookup_addr = NULL; - } - - if (sb && !pb->lookup_addr) - { - if (!pb->addrlen) abort(); - send_ping (pd, sb); - pd->last_pinged = sb; - } - } - - pd->last_ping_time = now; - } - - return get_ping (ssd); -} - - -/* Returns a list of hosts to ping based on the "-ping" argument. - */ -static sonar_bogie * -parse_mode (sonar_sensor_data *ssd, char **error_ret, char **desc_ret, - const char *ping_arg, Bool ping_works_p) -{ - ping_data *pd = (ping_data *) ssd->closure; - char *source, *token, *end, dummy; - sonar_bogie *hostlist = 0; - const char *fallback = "subnet"; - - AGAIN: - - if (fallback && (!ping_arg || !*ping_arg || !strcmp (ping_arg, "default"))) - source = strdup(fallback); - else if (ping_arg) - source = strdup(ping_arg); - else - return 0; - - token = source; - end = source + strlen(source); - while (token < end) - { - char *next; - sonar_bogie *new = 0; -# ifdef READ_FILES - struct stat st; -# endif - unsigned int n0=0, n1=0, n2=0, n3=0, m=0; - char d; - - for (next = token; - *next && - *next != ',' && *next != ' ' && *next != '\t' && *next != '\n'; - next++) - ; - *next = 0; - - - if (pd->debug_p) - fprintf (stderr, "%s: parsing %s\n", progname, token); - - if (!ping_works_p) - { -# ifdef HAVE_LIBCAP - *error_ret = strdup ("Sonar must be setuid or libcap to ping!\n" - "Running simulation instead."); -# else - *error_ret = strdup ("Sonar must be setuid to ping!\n" - "Running simulation instead."); -# endif - return 0; - } - - if ((4 == sscanf (token, "%u.%u.%u/%u %c", &n0,&n1,&n2, &m,&d)) || - (5 == sscanf (token, "%u.%u.%u.%u/%u %c", &n0,&n1,&n2,&n3,&m,&d))) - { - /* subnet: A.B.C.D/M - subnet: A.B.C/M - */ - unsigned long ip = pack_addr (n0, n1, n2, n3); - new = subnet_hosts (ssd, error_ret, desc_ret, ip, m); - } - else if (4 == sscanf (token, "%u.%u.%u.%u %c", &n0, &n1, &n2, &n3, &d)) - { - /* IP: A.B.C.D - */ - new = bogie_for_host (ssd, token, NULL); - } - else if (!strcmp (token, "subnet")) - { - new = subnet_hosts (ssd, error_ret, desc_ret, 0, 24); - } - else if (1 == sscanf (token, "subnet/%u %c", &m, &dummy)) - { - new = subnet_hosts (ssd, error_ret, desc_ret, 0, m); - } - else if (*token == '.' || *token == '/' || - *token == '$' || *token == '~') - { -# ifdef READ_FILES - new = read_hosts_file (ssd, token); -# else - if (pd->debug_p) fprintf (stderr, "%s: skipping file\n", progname); -# endif - } -# ifdef READ_FILES - else if (!stat (token, &st)) - { - new = read_hosts_file (ssd, token); - } -# endif /* READ_FILES */ - else - { - /* not an existant file - must be a host name - */ - new = bogie_for_host (ssd, token, NULL); - } - - if (new) - { - sonar_bogie *nn = new; - while (nn->next) - nn = nn->next; - nn->next = hostlist; - hostlist = new; - } - - token = next + 1; - while (token < end && - (*token == ',' || *token == ' ' || - *token == '\t' || *token == '\n')) - token++; - } - - free (source); - - /* If the arg was completely unparsable, fall back to the local subnet. - This happens if the default is "/etc/hosts" but READ_FILES is off. - Or if we're on a /31 network, in which case we try twice then fail. - */ - if (!hostlist && fallback) - { - if (pd->debug_p) - fprintf (stderr, "%s: no hosts parsed! Trying %s\n", - progname, fallback); - ping_arg = fallback; - fallback = 0; - goto AGAIN; - } - - return hostlist; -} - - -static Bool -set_net_raw_capalibity(int enable_p) -{ - Bool ret_status = False; -# ifdef HAVE_LIBCAP - cap_t cap_status; - cap_value_t cap_value[] = { CAP_NET_RAW, }; - cap_flag_value_t cap_flag_value; - cap_flag_value_t new_value = enable_p ? CAP_SET : CAP_CLEAR; - - cap_status = cap_get_proc(); - do { - cap_flag_value = CAP_CLEAR; - if (cap_get_flag (cap_status, CAP_NET_RAW, CAP_EFFECTIVE, &cap_flag_value)) - break; - if (cap_flag_value == new_value) - { - ret_status = True; - break; - } - - cap_set_flag (cap_status, CAP_EFFECTIVE, 1, cap_value, new_value); - if (!cap_set_proc(cap_status)) - ret_status = True; - } while (0); - - if (cap_status) cap_free (cap_status); -# endif /* HAVE_LIBCAP */ - - return ret_status; -} - -static Bool -set_ping_capability (void) -{ - if (geteuid() == 0) return True; - return set_net_raw_capalibity (True); -} - - -sonar_sensor_data * -sonar_init_ping (Display *dpy, char **error_ret, char **desc_ret, - const char *subnet, int timeout, - Bool resolve_p, Bool times_p, Bool debug_p) -{ - /* Important! Do not return from this function without disavowing privileges - with setuid(getuid()). - */ - sonar_sensor_data *ssd = (sonar_sensor_data *) calloc (1, sizeof(*ssd)); - ping_data *pd = (ping_data *) calloc (1, sizeof(*pd)); - sonar_bogie *b; - char *s; - - Bool socket_initted_p = False; - Bool socket_raw_p = False; - - pd->dpy = dpy; - - pd->resolve_p = resolve_p; - pd->times_p = times_p; - pd->debug_p = debug_p; - - ssd->closure = pd; - ssd->scan_cb = ping_scan; - ssd->free_data_cb = ping_free_data; - ssd->free_bogie_cb = ping_free_bogie_data; - - /* Get short version number. */ - s = strchr (screensaver_id, ' '); - pd->version = strdup (s+1); - s = strchr (pd->version, ' '); - *s = 0; - - - /* Create the ICMP socket. Do this before dropping privs. - - Raw sockets can only be opened by root (or setuid root), so we only try - to do this when the effective uid is 0. - - We used to just always try, and notice the failure. But apparently that - causes "SELinux" to log spurious warnings when running with the "strict" - policy. So to avoid that, we just don't try unless we know it will work. - - On MacOS X, we can avoid the whole problem by using a non-privileged - datagram instead of a raw socket. - - On recent Linux systems (2012-ish?) we can avoid setuid by instead using - cap_set_flag(... CAP_NET_RAW). To make that call the executable needs to - have "sudo setcap cap_net_raw=p sonar" done to it first. - - Except, it turns out that $MESA_LOADER_DRIVER_OVERRIDE would then let you - run arbitrary other programs with access to raw sockets. It's possible - that un-setting $MESA_LOADER_DRIVER_OVERRIDE early in main() would prevent - this, but Mesa uses a ton of environment variables, and who knows what - other crap is lurking in there. So that's just great. - - Ironically, being setuid root is *more* secure, as Mesa happens to contain - code that says, "Hey, maybe I shouldn't link in arbitrary other .so files - when I'm root". - - This trick does not work with $LD_PRELOAD because the kernel checks auxv - for AT_SECURE and won't run $LD_PRELOAD if setcap is in use, whereas Mesa - only checks geteuid. - */ - if (global_icmpsock) - { - pd->icmpsock = global_icmpsock; - socket_initted_p = True; - if (debug_p) - fprintf (stderr, "%s: re-using icmp socket\n", progname); - - } - else if ((pd->icmpsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_ICMP)) >= 0) - { - socket_initted_p = True; - } - else if (set_ping_capability() && - (pd->icmpsock = socket(AF_INET, SOCK_RAW, IPPROTO_ICMP)) >= 0) - { - socket_initted_p = True; - socket_raw_p = True; - } - - if (socket_initted_p) - { - global_icmpsock = pd->icmpsock; - socket_initted_p = True; - if (debug_p) - fprintf (stderr, "%s: opened %s icmp socket\n", progname, - (socket_raw_p ? "raw" : "dgram")); - } - else if (debug_p) - fprintf (stderr, "%s: unable to open icmp socket\n", progname); - - /* Disavow privs */ - if (setuid(getuid()) == -1) abort(); - - pd->pid = getpid() & 0xFFFF; - pd->seq = 0; - pd->timeout = timeout; - - /* Generate a list of targets */ - - pd->targets = parse_mode (ssd, error_ret, desc_ret, subnet, - socket_initted_p); - pd->targets = delete_duplicate_hosts (ssd, pd->targets); - - if (debug_p) - { - fprintf (stderr, "%s: Target list:\n", progname); - for (b = pd->targets; b; b = b->next) - { - fprintf (stderr, "%s: ", progname); - print_host (stderr, b); - } - } - - /* Make sure there is something to ping */ - - pd->target_count = 0; - for (b = pd->targets; b; b = b->next) - pd->target_count++; - - if (pd->target_count == 0) - { - if (! *error_ret) - *error_ret = strdup ("No hosts to ping!\n" - "Simulating instead."); - ping_free_data (ssd, pd); - if (ssd) free (ssd); - return 0; - } - - /* Distribute them evenly around the display field, clockwise. - Even on a /24, allocated IPs tend to cluster together, so - don't put any two hosts closer together than N degrees to - avoid unnecessary overlap when we have plenty of space due - to addresses that probably won't respond. And don't spread - them out too far apart, because that looks too symmetrical - when there are a small number of hosts. - */ - { - double th = frand(M_PI); - double sep = 360.0 / pd->target_count; - if (sep < 23) sep = 23; - if (sep > 43) sep = 43; - sep /= 180/M_PI; - for (b = pd->targets; b; b = b->next) { - b->th = th; - th += sep; - } - } - - return ssd; -} - -#endif /* HAVE_PING -- whole file */ |