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-rw-r--r--qemu/roms/ipxe/src/util/hijack.c628
1 files changed, 0 insertions, 628 deletions
diff --git a/qemu/roms/ipxe/src/util/hijack.c b/qemu/roms/ipxe/src/util/hijack.c
deleted file mode 100644
index ed89592b1..000000000
--- a/qemu/roms/ipxe/src/util/hijack.c
+++ /dev/null
@@ -1,628 +0,0 @@
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <string.h>
-#include <stdarg.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <libgen.h>
-#include <signal.h>
-#include <net/if.h>
-#include <net/ethernet.h>
-#include <sys/select.h>
-#include <sys/socket.h>
-#include <sys/stat.h>
-#include <sys/un.h>
-#include <syslog.h>
-#include <getopt.h>
-#include <pcap.h>
-
-#define SNAPLEN 1600
-
-/*
- * FIXME: is there a way to detect the version of the libpcap library?
- * Version 0.9 has pcap_inject; version 0.8 doesn't, but both report
- * their version number as 2.4.
- */
-#define HAVE_PCAP_INJECT 0
-
-struct hijack {
- pcap_t *pcap;
- int fd;
- int datalink;
- int filtered;
- unsigned long rx_count;
- unsigned long tx_count;
-};
-
-struct hijack_listener {
- struct sockaddr_un sun;
- int fd;
-};
-
-struct hijack_options {
- char interface[IF_NAMESIZE];
- int daemonise;
-};
-
-static int daemonised = 0;
-
-static int signalled = 0;
-
-static void flag_signalled ( int signal __attribute__ (( unused )) ) {
- signalled = 1;
-}
-
-#if ! HAVE_PCAP_INJECT
-/**
- * Substitute for pcap_inject(), if this version of libpcap doesn't
- * have it. Will almost certainly only work under Linux.
- *
- */
-int pcap_inject ( pcap_t *pcap, const void *data, size_t len ) {
- int fd;
- char *errbuf = pcap_geterr ( pcap );
-
- fd = pcap_get_selectable_fd ( pcap );
- if ( fd < 0 ) {
- snprintf ( errbuf, PCAP_ERRBUF_SIZE,
- "could not get file descriptor" );
- return -1;
- }
- if ( write ( fd, data, len ) != len ) {
- snprintf ( errbuf, PCAP_ERRBUF_SIZE,
- "could not write data: %s", strerror ( errno ) );
- return -1;
- }
- return len;
-}
-#endif /* ! HAVE_PCAP_INJECT */
-
-/**
- * Log error message
- *
- */
-static __attribute__ (( format ( printf, 2, 3 ) )) void
-logmsg ( int level, const char *format, ... ) {
- va_list ap;
-
- va_start ( ap, format );
- if ( daemonised ) {
- vsyslog ( ( LOG_DAEMON | level ), format, ap );
- } else {
- vfprintf ( stderr, format, ap );
- }
- va_end ( ap );
-}
-
-/**
- * Open pcap device
- *
- */
-static int hijack_open ( const char *interface, struct hijack *hijack ) {
- char errbuf[PCAP_ERRBUF_SIZE];
-
- /* Open interface via pcap */
- errbuf[0] = '\0';
- hijack->pcap = pcap_open_live ( interface, SNAPLEN, 1, 0, errbuf );
- if ( ! hijack->pcap ) {
- logmsg ( LOG_ERR, "Failed to open %s: %s\n",
- interface, errbuf );
- goto err;
- }
- if ( errbuf[0] )
- logmsg ( LOG_WARNING, "Warning: %s\n", errbuf );
-
- /* Set capture interface to non-blocking mode */
- if ( pcap_setnonblock ( hijack->pcap, 1, errbuf ) < 0 ) {
- logmsg ( LOG_ERR, "Could not make %s non-blocking: %s\n",
- interface, errbuf );
- goto err;
- }
-
- /* Get file descriptor for select() */
- hijack->fd = pcap_get_selectable_fd ( hijack->pcap );
- if ( hijack->fd < 0 ) {
- logmsg ( LOG_ERR, "Cannot get selectable file descriptor "
- "for %s\n", interface );
- goto err;
- }
-
- /* Get link layer type */
- hijack->datalink = pcap_datalink ( hijack->pcap );
-
- return 0;
-
- err:
- if ( hijack->pcap )
- pcap_close ( hijack->pcap );
- return -1;
-}
-
-/**
- * Close pcap device
- *
- */
-static void hijack_close ( struct hijack *hijack ) {
- pcap_close ( hijack->pcap );
-}
-
-/**
- * Install filter for hijacked connection
- *
- */
-static int hijack_install_filter ( struct hijack *hijack,
- char *filter ) {
- struct bpf_program program;
-
- /* Compile filter */
- if ( pcap_compile ( hijack->pcap, &program, filter, 1, 0 ) < 0 ) {
- logmsg ( LOG_ERR, "could not compile filter \"%s\": %s\n",
- filter, pcap_geterr ( hijack->pcap ) );
- goto err_nofree;
- }
-
- /* Install filter */
- if ( pcap_setfilter ( hijack->pcap, &program ) < 0 ) {
- logmsg ( LOG_ERR, "could not install filter \"%s\": %s\n",
- filter, pcap_geterr ( hijack->pcap ) );
- goto err;
- }
-
- logmsg ( LOG_INFO, "using filter \"%s\"\n", filter );
-
- pcap_freecode ( &program );
- return 0;
-
- err:
- pcap_freecode ( &program );
- err_nofree:
- return -1;
-}
-
-/**
- * Set up filter for hijacked ethernet connection
- *
- */
-static int hijack_filter_ethernet ( struct hijack *hijack, const char *buf,
- size_t len ) {
- char filter[55]; /* see format string */
- struct ether_header *ether_header = ( struct ether_header * ) buf;
- unsigned char *hwaddr = ether_header->ether_shost;
-
- if ( len < sizeof ( *ether_header ) )
- return -1;
-
- snprintf ( filter, sizeof ( filter ), "broadcast or multicast or "
- "ether host %02x:%02x:%02x:%02x:%02x:%02x", hwaddr[0],
- hwaddr[1], hwaddr[2], hwaddr[3], hwaddr[4], hwaddr[5] );
-
- return hijack_install_filter ( hijack, filter );
-}
-
-/**
- * Set up filter for hijacked connection
- *
- */
-static int hijack_filter ( struct hijack *hijack, const char *buf,
- size_t len ) {
- switch ( hijack->datalink ) {
- case DLT_EN10MB:
- return hijack_filter_ethernet ( hijack, buf, len );
- default:
- logmsg ( LOG_ERR, "unsupported protocol %s: cannot filter\n",
- ( pcap_datalink_val_to_name ( hijack->datalink ) ?
- pcap_datalink_val_to_name ( hijack->datalink ) :
- "UNKNOWN" ) );
- /* Return success so we don't get called again */
- return 0;
- }
-}
-
-/**
- * Forward data from hijacker
- *
- */
-static ssize_t forward_from_hijacker ( struct hijack *hijack, int fd ) {
- char buf[SNAPLEN];
- ssize_t len;
-
- /* Read packet from hijacker */
- len = read ( fd, buf, sizeof ( buf ) );
- if ( len < 0 ) {
- logmsg ( LOG_ERR, "read from hijacker failed: %s\n",
- strerror ( errno ) );
- return -1;
- }
- if ( len == 0 )
- return 0;
-
- /* Set up filter if not already in place */
- if ( ! hijack->filtered ) {
- if ( hijack_filter ( hijack, buf, len ) == 0 )
- hijack->filtered = 1;
- }
-
- /* Transmit packet to network */
- if ( pcap_inject ( hijack->pcap, buf, len ) != len ) {
- logmsg ( LOG_ERR, "write to hijacked port failed: %s\n",
- pcap_geterr ( hijack->pcap ) );
- return -1;
- }
-
- hijack->tx_count++;
- return len;
-};
-
-/**
- * Forward data to hijacker
- *
- */
-static ssize_t forward_to_hijacker ( int fd, struct hijack *hijack ) {
- struct pcap_pkthdr *pkt_header;
- const unsigned char *pkt_data;
- ssize_t len;
-
- /* Receive packet from network */
- if ( pcap_next_ex ( hijack->pcap, &pkt_header, &pkt_data ) < 0 ) {
- logmsg ( LOG_ERR, "read from hijacked port failed: %s\n",
- pcap_geterr ( hijack->pcap ) );
- return -1;
- }
- if ( pkt_header->caplen != pkt_header->len ) {
- logmsg ( LOG_ERR, "read partial packet (%d of %d bytes)\n",
- pkt_header->caplen, pkt_header->len );
- return -1;
- }
- if ( pkt_header->caplen == 0 )
- return 0;
- len = pkt_header->caplen;
-
- /* Write packet to hijacker */
- if ( write ( fd, pkt_data, len ) != len ) {
- logmsg ( LOG_ERR, "write to hijacker failed: %s\n",
- strerror ( errno ) );
- return -1;
- }
-
- hijack->rx_count++;
- return len;
-};
-
-
-/**
- * Run hijacker
- *
- */
-static int run_hijacker ( const char *interface, int fd ) {
- struct hijack hijack;
- fd_set fdset;
- int max_fd;
- ssize_t len;
-
- logmsg ( LOG_INFO, "new connection for %s\n", interface );
-
- /* Open connection to network */
- memset ( &hijack, 0, sizeof ( hijack ) );
- if ( hijack_open ( interface, &hijack ) < 0 )
- goto err;
-
- /* Do the forwarding */
- max_fd = ( ( fd > hijack.fd ) ? fd : hijack.fd );
- while ( 1 ) {
- /* Wait for available data */
- FD_ZERO ( &fdset );
- FD_SET ( fd, &fdset );
- FD_SET ( hijack.fd, &fdset );
- if ( select ( ( max_fd + 1 ), &fdset, NULL, NULL, 0 ) < 0 ) {
- logmsg ( LOG_ERR, "select failed: %s\n",
- strerror ( errno ) );
- goto err;
- }
- if ( FD_ISSET ( fd, &fdset ) ) {
- len = forward_from_hijacker ( &hijack, fd );
- if ( len < 0 )
- goto err;
- if ( len == 0 )
- break;
- }
- if ( FD_ISSET ( hijack.fd, &fdset ) ) {
- len = forward_to_hijacker ( fd, &hijack );
- if ( len < 0 )
- goto err;
- if ( len == 0 )
- break;
- }
- }
-
- hijack_close ( &hijack );
- logmsg ( LOG_INFO, "closed connection for %s\n", interface );
- logmsg ( LOG_INFO, "received %ld packets, sent %ld packets\n",
- hijack.rx_count, hijack.tx_count );
-
- return 0;
-
- err:
- if ( hijack.pcap )
- hijack_close ( &hijack );
- return -1;
-}
-
-/**
- * Open listener socket
- *
- */
-static int open_listener ( const char *interface,
- struct hijack_listener *listener ) {
-
- /* Create socket */
- listener->fd = socket ( PF_UNIX, SOCK_SEQPACKET, 0 );
- if ( listener->fd < 0 ) {
- logmsg ( LOG_ERR, "Could not create socket: %s\n",
- strerror ( errno ) );
- goto err;
- }
-
- /* Bind to local filename */
- listener->sun.sun_family = AF_UNIX,
- snprintf ( listener->sun.sun_path, sizeof ( listener->sun.sun_path ),
- "/var/run/hijack-%s", interface );
- if ( bind ( listener->fd, ( struct sockaddr * ) &listener->sun,
- sizeof ( listener->sun ) ) < 0 ) {
- logmsg ( LOG_ERR, "Could not bind socket to %s: %s\n",
- listener->sun.sun_path, strerror ( errno ) );
- goto err;
- }
-
- /* Set as a listening socket */
- if ( listen ( listener->fd, 0 ) < 0 ) {
- logmsg ( LOG_ERR, "Could not listen to %s: %s\n",
- listener->sun.sun_path, strerror ( errno ) );
- goto err;
- }
-
- return 0;
-
- err:
- if ( listener->fd >= 0 )
- close ( listener->fd );
- return -1;
-}
-
-/**
- * Listen on listener socket
- *
- */
-static int listen_for_hijackers ( struct hijack_listener *listener,
- const char *interface ) {
- int fd;
- pid_t child;
- int rc;
-
- logmsg ( LOG_INFO, "Listening on %s\n", listener->sun.sun_path );
-
- while ( ! signalled ) {
- /* Accept new connection, interruptibly */
- siginterrupt ( SIGINT, 1 );
- siginterrupt ( SIGHUP, 1 );
- fd = accept ( listener->fd, NULL, 0 );
- siginterrupt ( SIGINT, 0 );
- siginterrupt ( SIGHUP, 0 );
- if ( fd < 0 ) {
- if ( errno == EINTR ) {
- continue;
- } else {
- logmsg ( LOG_ERR, "accept failed: %s\n",
- strerror ( errno ) );
- goto err;
- }
- }
-
- /* Fork child process */
- child = fork();
- if ( child < 0 ) {
- logmsg ( LOG_ERR, "fork failed: %s\n",
- strerror ( errno ) );
- goto err;
- }
- if ( child == 0 ) {
- /* I am the child; run the hijacker */
- rc = run_hijacker ( interface, fd );
- close ( fd );
- exit ( rc );
- }
-
- close ( fd );
- }
-
- logmsg ( LOG_INFO, "Stopped listening on %s\n",
- listener->sun.sun_path );
- return 0;
-
- err:
- if ( fd >= 0 )
- close ( fd );
- return -1;
-}
-
-/**
- * Close listener socket
- *
- */
-static void close_listener ( struct hijack_listener *listener ) {
- close ( listener->fd );
- unlink ( listener->sun.sun_path );
-}
-
-/**
- * Print usage
- *
- */
-static void usage ( char **argv ) {
- logmsg ( LOG_ERR,
- "Usage: %s [options]\n"
- "\n"
- "Options:\n"
- " -h|--help Print this help message\n"
- " -i|--interface intf Use specified network interface\n"
- " -n|--nodaemon Run in foreground\n",
- argv[0] );
-}
-
-/**
- * Parse command-line options
- *
- */
-static int parse_options ( int argc, char **argv,
- struct hijack_options *options ) {
- static struct option long_options[] = {
- { "interface", 1, NULL, 'i' },
- { "nodaemon", 0, NULL, 'n' },
- { "help", 0, NULL, 'h' },
- { },
- };
- int c;
-
- /* Set default options */
- memset ( options, 0, sizeof ( *options ) );
- strncpy ( options->interface, "eth0", sizeof ( options->interface ) );
- options->daemonise = 1;
-
- /* Parse command-line options */
- while ( 1 ) {
- int option_index = 0;
-
- c = getopt_long ( argc, argv, "i:hn", long_options,
- &option_index );
- if ( c < 0 )
- break;
-
- switch ( c ) {
- case 'i':
- strncpy ( options->interface, optarg,
- sizeof ( options->interface ) );
- break;
- case 'n':
- options->daemonise = 0;
- break;
- case 'h':
- usage( argv );
- return -1;
- case '?':
- /* Unrecognised option */
- return -1;
- default:
- logmsg ( LOG_ERR, "Unrecognised option '-%c'\n", c );
- return -1;
- }
- }
-
- /* Check there's nothing left over on the command line */
- if ( optind != argc ) {
- usage ( argv );
- return -1;
- }
-
- return 0;
-}
-
-/**
- * Daemonise
- *
- */
-static int daemonise ( const char *interface ) {
- char pidfile[16 + IF_NAMESIZE + 4]; /* "/var/run/hijack-<intf>.pid" */
- char pid[16];
- int pidlen;
- int fd = -1;
-
- /* Daemonise */
- if ( daemon ( 0, 0 ) < 0 ) {
- logmsg ( LOG_ERR, "Could not daemonise: %s\n",
- strerror ( errno ) );
- goto err;
- }
- daemonised = 1; /* Direct messages to syslog now */
-
- /* Open pid file */
- snprintf ( pidfile, sizeof ( pidfile ), "/var/run/hijack-%s.pid",
- interface );
- fd = open ( pidfile, ( O_WRONLY | O_CREAT | O_TRUNC ),
- ( S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH ) );
- if ( fd < 0 ) {
- logmsg ( LOG_ERR, "Could not open %s for writing: %s\n",
- pidfile, strerror ( errno ) );
- goto err;
- }
-
- /* Write pid to file */
- pidlen = snprintf ( pid, sizeof ( pid ), "%d\n", getpid() );
- if ( write ( fd, pid, pidlen ) != pidlen ) {
- logmsg ( LOG_ERR, "Could not write %s: %s\n",
- pidfile, strerror ( errno ) );
- goto err;
- }
-
- close ( fd );
- return 0;
-
- err:
- if ( fd >= 0 )
- close ( fd );
- return -1;
-}
-
-int main ( int argc, char **argv ) {
- struct hijack_options options;
- struct hijack_listener listener;
- struct sigaction sa;
-
- /* Parse command-line options */
- if ( parse_options ( argc, argv, &options ) < 0 )
- exit ( 1 );
-
- /* Set up syslog connection */
- openlog ( basename ( argv[0] ), LOG_PID, LOG_DAEMON );
-
- /* Set up listening socket */
- if ( open_listener ( options.interface, &listener ) < 0 )
- exit ( 1 );
-
- /* Daemonise on demand */
- if ( options.daemonise ) {
- if ( daemonise ( options.interface ) < 0 )
- exit ( 1 );
- }
-
- /* Avoid creating zombies */
- memset ( &sa, 0, sizeof ( sa ) );
- sa.sa_handler = SIG_IGN;
- sa.sa_flags = SA_RESTART | SA_NOCLDWAIT;
- if ( sigaction ( SIGCHLD, &sa, NULL ) < 0 ) {
- logmsg ( LOG_ERR, "Could not set SIGCHLD handler: %s",
- strerror ( errno ) );
- exit ( 1 );
- }
-
- /* Set 'signalled' flag on SIGINT or SIGHUP */
- sa.sa_handler = flag_signalled;
- sa.sa_flags = SA_RESTART | SA_RESETHAND;
- if ( sigaction ( SIGINT, &sa, NULL ) < 0 ) {
- logmsg ( LOG_ERR, "Could not set SIGINT handler: %s",
- strerror ( errno ) );
- exit ( 1 );
- }
- if ( sigaction ( SIGHUP, &sa, NULL ) < 0 ) {
- logmsg ( LOG_ERR, "Could not set SIGHUP handler: %s",
- strerror ( errno ) );
- exit ( 1 );
- }
-
- /* Listen for hijackers */
- if ( listen_for_hijackers ( &listener, options.interface ) < 0 )
- exit ( 1 );
-
- close_listener ( &listener );
-
- return 0;
-}