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-rw-r--r--jawol.c243
1 files changed, 229 insertions, 14 deletions
diff --git a/jawol.c b/jawol.c
index 8c06878..481fafe 100644
--- a/jawol.c
+++ b/jawol.c
@@ -38,6 +38,13 @@ static const char usage_msg[] =
" --destination IPADDR\n"
" -d IPADDR Destination (broadcast) IP address.\n"
"\n"
+"Options for listening for WOL packets:\n"
+" --listen\n"
+" -l Listen for incoming WOL packets and print their contents.\n"
+" Pass twice to force listening for UDP and RAW packets and\n"
+" bail out if this fails. Otherwise, continue as long as at\n"
+" least one of the sockets could be bound successfully.\n"
+"\n"
"Common options:\n"
" --verbose\n"
" -v Verbose mode, print some additional information.\n"
@@ -69,6 +76,8 @@ static const char usage_msg[] =
#include <linux/if.h>
#include <sys/ioctl.h>
#include <getopt.h>
+#include <poll.h>
+#include <fcntl.h>
#define PACKET_SIZE (200)
#define CHECK_PACKET_SIZE(x) do { \
@@ -96,6 +105,12 @@ static int rawsocket();
static int udpsocket();
static int etherwake(int count, char **macs);
static int wakeonlan(int count, char **maclist);
+static int wolisten(bool force);
+static int rawrecv(int sock);
+static int udprecv(int sock);
+static int find_wol(const char *addr, const char *buffer, size_t buflen, const char *type);
+static void formatpw(const uint8_t *pw, int len, char *output, size_t outlen);
+static void sock_nonblock(int sock);
static void print_usage(const char *a0)
{
@@ -104,9 +119,9 @@ static void print_usage(const char *a0)
int main(int argc, char **argv)
{
- int opt;
+ int opt, dolisten = 0;
bool gotip = false, gotif = false;
- static const char *optString = "bDi:p:vhd:";
+ static const char *optString = "bDi:p:vhd:l";
static const struct option longOpts[] = {
{ "broadcast", no_argument, NULL, 'b' },
{ "debug", no_argument, NULL, 'D' },
@@ -115,6 +130,7 @@ int main(int argc, char **argv)
{ "verbose", no_argument, NULL, 'v' },
{ "help", no_argument, NULL, 'h' },
{ "destination", required_argument, NULL, 'd' },
+ { "listen", no_argument, NULL, 'l' },
{ 0, 0, 0, 0 }
};
// Conveinience: Support MAC addr with dashes
@@ -134,9 +150,17 @@ int main(int argc, char **argv)
case 'v': options.verbose = true; break;
case 'h': print_usage( argv[0] ); return 0;
case 'd': options.dest = get_ip( optarg ); gotip = true; break;
+ case 'l': dolisten++; break;
case '?': parse_errors++; break;
}
}
+ if ( dolisten && ( gotip || gotif || optind < argc ) ) {
+ fprintf( stderr, "Cannot combine -l with any other options.\n" );
+ return 1;
+ }
+ if ( dolisten ) {
+ return wolisten( dolisten > 1 );
+ }
if ( gotip && gotif ) {
fprintf( stderr, "Cannot use -d and -b/-i at the same time.\n" );
parse_errors++;
@@ -252,13 +276,13 @@ static int rawsocket()
if (errno == EPERM) {
fprintf(stderr, "This program must be run as root for raw mode to work.\n");
} else {
- perror("socket");
+ perror("RAW socket()");
}
return -1;
}
/* This is necessary for broadcasts to work */
if ( setsockopt( s, SOL_SOCKET, SO_BROADCAST, (char *)&one, sizeof(one) ) == -1 ) {
- perror( "setsockopt: SO_BROADCAST" );
+ perror( "RAW setsockopt: SO_BROADCAST" );
return -1;
}
return s;
@@ -271,11 +295,11 @@ int udpsocket()
sock = socket( AF_INET, SOCK_DGRAM, IPPROTO_UDP );
if ( sock == -1 ) {
- perror( "socket" );
+ perror( "UDP socket()" );
return -1;
}
if ( setsockopt( sock, SOL_SOCKET, SO_BROADCAST, (char *) &optval, sizeof( optval ) ) == -1 ) {
- perror( "setsockopt: SO_BROADCAST" );
+ perror( "UDP setsockopt: SO_BROADCAST" );
return -1;
}
@@ -377,12 +401,20 @@ static void get_wol_pw(const char *optarg)
fprintf(stderr, "The impossible happened.\n");
abort();
}
- printf(" The Magic packet password is %2.2x %2.2x %2.2x %2.2x (%d).\n",
- passwd[0], passwd[1], passwd[2], passwd[3], byte_cnt);
options.wolpwlen = byte_cnt;
for (i = 0; i < byte_cnt; i++) {
+ if ( passwd[i] > 255 ) {
+ fprintf( stderr, "Password has invalid value for byte %d: %u.\n",
+ i, passwd[i] );
+ parse_errors++;
+ }
options.wolpw[i] = passwd[i];
}
+ if ( options.verbose ) {
+ char pw[20];
+ formatpw( (uint8_t*)options.wolpw + i, byte_cnt, pw, sizeof(pw) );
+ printf("The Magic packet password is %s.\n", pw);
+ }
}
/**
@@ -406,11 +438,10 @@ static int get_source_addr(int s, const char *ifname, unsigned char *output)
memcpy(output, if_hwaddr.ifr_hwaddr.sa_data, 6);
if ( options.verbose ) {
- unsigned char *hwaddr = (unsigned char*)if_hwaddr.ifr_hwaddr.sa_data;
- printf("The hardware address (SIOCGIFHWADDR) of %s is type %d "
- "%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x.\n", ifname,
- if_hwaddr.ifr_hwaddr.sa_family, hwaddr[0], hwaddr[1],
- hwaddr[2], hwaddr[3], hwaddr[4], hwaddr[5]);
+ char mac[20];
+ formatpw( (uint8_t*)if_hwaddr.ifr_hwaddr.sa_data, 6, mac, sizeof(mac) );
+ printf("The hardware address (SIOCGIFHWADDR) of %s is type %d"
+ " (%s).\n", ifname, if_hwaddr.ifr_hwaddr.sa_family, mac);
}
return 0;
}
@@ -440,7 +471,7 @@ static int get_dest_addr(const char *hostid, struct ether_addr *dest_ether)
}
} else {
fprintf(stderr,
- "ether-wake: The Magic Packet host address must be "
+ "The Magic Packet host address must be "
"specified as\n"
" - a station address, 00:11:22:33:44:55, or\n"
" - a station address, 00-11-22-33-44-55, or\n"
@@ -460,3 +491,187 @@ static struct in_addr get_ip(const char *arg)
return tmp;
}
+static int wolisten(bool force)
+{
+ // TODO: RAW
+ struct pollfd socks[2] = {{.events = POLLIN},{.events = POLLIN}};
+ int num = 0;
+ // UDP setup
+ int su = udpsocket();
+ if ( su == -1 ) {
+ if ( force )
+ return 1;
+ } else {
+ struct sockaddr_in addr = {
+ .sin_family = AF_INET,
+ .sin_port = htons( 9 ),
+ .sin_addr = { INADDR_ANY },
+ };
+ socklen_t addrlen = sizeof(addr);
+ sock_nonblock( su );
+ if ( bind( su, (struct sockaddr*)&addr, addrlen ) == -1 ) {
+ perror( "bind on UDP socket" );
+ close( su );
+ if ( force )
+ return 2;
+ } else {
+ socks[num++].fd = su;
+ if ( options.verbose ) {
+ printf( "Listening for UDP WOL packets\n" );
+ }
+ }
+ }
+ // RAW setup
+ int sr = rawsocket();
+ if ( sr == -1 ) {
+ if ( force )
+ return 1;
+ } else {
+ struct sockaddr_ll addr = {
+ .sll_protocol = htons( 0x0842 ),
+ .sll_family = AF_PACKET,
+ };
+ socklen_t addrlen = sizeof(addr);
+ sock_nonblock( sr );
+ if ( bind( sr, (struct sockaddr*)&addr, addrlen ) == -1 ) {
+ perror( "bind on RAW socket" );
+ close( sr );
+ if ( force )
+ return 2;
+ } else {
+ socks[num++].fd = sr;
+ if ( options.verbose ) {
+ printf( "Listening for RAW WOL packets\n" );
+ }
+ }
+ }
+ // Ready to go?
+ if ( num == 0 )
+ return 1;
+ for ( ;; ) {
+ if ( poll( socks, num, -1 ) == -1 ) {
+ if ( errno == EINTR || errno == EAGAIN )
+ continue;
+ perror( "poll" );
+ break;
+ }
+ for ( int i = 0; i < num; ++i ) {
+ if ( socks[i].revents == 0 )
+ continue;
+ if ( socks[i].fd == su ) {
+ udprecv( su );
+ } else if ( socks[i].fd == sr ) {
+ rawrecv( sr );
+ } else {
+ abort();
+ }
+ }
+ }
+ close( su );
+ return 1;
+}
+
+static const uint8_t ETHER_HEADER_LEN = 6 + 6 + 2; // 2x MAC + type
+
+static int rawrecv(int sock)
+{
+ char buffer[PACKET_SIZE], addrstr[50];
+ struct sockaddr_ll src = {0};
+ socklen_t srclen = sizeof(src);
+ ssize_t ret = recvfrom( sock, buffer, sizeof(buffer), 0, (struct sockaddr*)&src, &srclen );
+ if ( ret < 0 ) {
+ if ( errno == EINTR || errno == EAGAIN )
+ return 0;
+ perror( "recvfrom for RAW socket" );
+ return 1;
+ }
+ if ( ret < ETHER_HEADER_LEN ) {
+ printf( "Short raw packet received (%d bytes)\n", (int)ret );
+ return 0;
+ }
+ formatpw( (uint8_t*)src.sll_addr, src.sll_halen, addrstr, sizeof(addrstr) );
+ if ( options.debug ) {
+ printf( "Received RAW packet of size %d from %s!\n", (int)ret, addrstr );
+ }
+ return find_wol( addrstr, buffer + ETHER_HEADER_LEN, (size_t)ret - ETHER_HEADER_LEN, "RAW" );
+}
+
+static int udprecv(int sock)
+{
+ char buffer[PACKET_SIZE], addrstr[50];
+ struct sockaddr_in src = {0};
+ socklen_t srclen = sizeof(src);
+ ssize_t ret = recvfrom( sock, buffer, sizeof(buffer), 0, (struct sockaddr*)&src, &srclen );
+ if ( ret < 0 ) {
+ if ( errno == EINTR || errno == EAGAIN )
+ return 0;
+ perror( "recvfrom for UDP socket" );
+ return 1;
+ }
+ if ( inet_ntop( AF_INET, &src.sin_addr, addrstr, sizeof(addrstr) ) == NULL ) {
+ perror( "Cannot determine source address of received UDP packet" );
+ return 0;
+ }
+ if ( options.debug ) {
+ printf( "Received UDP datagram of size %d from %s!\n", (int)ret, addrstr );
+ }
+ return find_wol( addrstr, buffer, (size_t)ret, "UDP" );
+}
+
+static int find_wol(const char *addrstr, const char *buffer, size_t buflen, const char *type)
+{
+ const uint8_t *sync = (uint8_t*)memmem( buffer, buflen, "\xff\xff\xff\xff\xff\xff", 6 );
+ if ( sync == NULL ) {
+ if ( options.debug ) {
+ printf( "... no sync bytes found\n" );
+ }
+ return 0;
+ }
+ sync += 6;
+ const uint8_t *end = (uint8_t*)buffer + buflen;
+ const uint8_t *pos = sync;
+ int count = 0;
+ while ( count < 16 && pos + 6 <= end ) {
+ if ( memcmp( sync, pos, 6 ) != 0 )
+ break;
+ pos += 6;
+ count++;
+ }
+ if ( count == 16 ) {
+ char passwd[20];
+ char mac[20];
+ formatpw( sync, 6, mac, sizeof(mac) );
+ formatpw( pos, end - pos, passwd, sizeof(passwd) );
+ printf( "MAGIC source=%s dest=%s type=%s passwd=%s\n", addrstr, mac, type, passwd );
+ } else if ( options.verbose ) {
+ printf( "Sync bytes found, with %d repetitions of the following 6 bytes.\n", count );
+ }
+ return 0;
+}
+
+static void formatpw(const uint8_t *pw, int len, char *output, size_t outlen)
+{
+ if ( outlen <= 0 )
+ return;
+ if ( len == 4 ) {
+ snprintf( output, outlen, "%u.%u.%u.%u", pw[0], pw[1], pw[2], pw[3] );
+ } else if ( len == 6 ) {
+ snprintf( output, outlen, "%02x:%02x:%02x:%02x:%02x:%02x", pw[0], pw[1], pw[2], pw[3], pw[4], pw[5] );
+ } else {
+ *output = '\0';
+ }
+}
+
+static void sock_nonblock(int sock)
+{
+ errno = 0;
+ int f = fcntl( sock, F_GETFL );
+ if ( errno != 0 ) {
+ perror( "fcntl(F_GETFL)" );
+ return;
+ }
+ if ( fcntl( sock, F_SETFL, f | O_NONBLOCK ) == -1 ) {
+ perror( "fcntl(F_SETFL, ... | O_NONBLOCK)" );
+ }
+}
+
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-11-21 17:58:18 +0100