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authorNathan Binkert <binkertn@umich.edu>2005-06-27 19:30:19 -0400
committerNathan Binkert <binkertn@umich.edu>2005-06-27 19:30:19 -0400
commit769234f69e10a923fb4251996746b31d84c9357a (patch)
tree9f90ca74232da95789ef6102a20a158535bd044c /util/tap/tap.cc
parent10a906be528df1e7495a68f415833a27e8279840 (diff)
downloadgem5-769234f69e10a923fb4251996746b31d84c9357a.tar.xz
Reorganize tap code so that more than one method can be used
for accessing physical packets. Add support for tap devices found on linux and bsd. --HG-- extra : convert_revision : 198b082f2e847da8471c3f22d6a55beb9f4b592e
Diffstat (limited to 'util/tap/tap.cc')
-rw-r--r--util/tap/tap.cc192
1 files changed, 154 insertions, 38 deletions
diff --git a/util/tap/tap.cc b/util/tap/tap.cc
index f07d49619..f4d0aadf2 100644
--- a/util/tap/tap.cc
+++ b/util/tap/tap.cc
@@ -173,7 +173,7 @@ Accept(int fd, bool nodelay)
}
void
-Connect(int fd, const string &host, int port)
+Connect(int fd, const std::string &host, int port)
{
struct sockaddr_in sockaddr;
if (::inet_aton(host.c_str(), &sockaddr.sin_addr) == 0) {
@@ -193,6 +193,133 @@ Connect(int fd, const string &host, int port)
DPRINTF("connected to %s on port %d\n", host, port);
}
+class Ethernet
+{
+ protected:
+ int fd;
+
+ public:
+ virtual ~Ethernet() {}
+
+ int getfd() const { return fd; }
+ virtual bool read(const char *&data, int &len) = 0;
+ virtual bool write(const char *data, int len) = 0;
+};
+
+class Tap : public Ethernet
+{
+ private:
+ char buffer[65536];
+ int fd;
+
+ public:
+ Tap(char *device);
+ ~Tap();
+ virtual bool read(const char *&data, int &len);
+ virtual bool write(const char *data, int len);
+};
+
+class PCap : public Ethernet
+{
+ private:
+ pcap_t *pcap;
+ eth_t *ethernet;
+
+ public:
+ PCap(char *device, char *filter = NULL);
+ ~PCap();
+ virtual bool read(const char *&data, int &len);
+ virtual bool write(const char *data, int len);
+};
+
+PCap::PCap(char *device, char *filter)
+{
+ char errbuf[PCAP_ERRBUF_SIZE];
+ memset(errbuf, 0, sizeof errbuf);
+ pcap = pcap_open_live(device, 1500, 1, -1, errbuf);
+ if (pcap == NULL)
+ panic("pcap_open_live failed: %s\n", errbuf);
+
+ if (filter) {
+ bpf_program program;
+ bpf_u_int32 localnet, netmask;
+ if (pcap_lookupnet(device, &localnet, &netmask, errbuf) == -1) {
+ DPRINTF("pcap_lookupnet failed: %s\n", errbuf);
+ netmask = 0xffffff00;
+ }
+
+ if (pcap_compile(pcap, &program, filter, 1, netmask) == -1)
+ panic("pcap_compile failed, invalid filter:\n%s\n", filter);
+
+ if (pcap_setfilter(pcap, &program) == -1)
+ panic("pcap_setfilter failed\n");
+ }
+
+ ethernet = eth_open(device);
+ if (!ethernet)
+ panic("cannot open the ethernet device for writing\n");
+
+ fd = pcap_fileno(pcap);
+}
+
+PCap::~PCap()
+{
+ pcap_close(pcap);
+ eth_close(ethernet);
+}
+
+bool
+PCap::read(const char *&data, int &len)
+{
+ pcap_pkthdr hdr;
+ data = (const char *)pcap_next(pcap, &hdr);
+ if (!data)
+ return false;
+
+ len = hdr.len;
+ return true;
+}
+
+bool
+PCap::write(const char *data, int len)
+{
+ eth_send(ethernet, data, len);
+}
+
+Tap::Tap(char *device)
+{
+ fd = open(device, O_RDWR, 0);
+ if (fd < 0)
+ panic("could not open %s: %s\n", device, strerror(errno));
+}
+
+Tap::~Tap()
+{
+ close(fd);
+}
+
+bool
+Tap::read(const char *&data, int &len)
+{
+ DPRINTF("tap read!\n");
+ data = buffer;
+ len = ::read(fd, buffer, sizeof(buffer));
+ if (len < 0)
+ return false;
+
+ return true;
+}
+
+bool
+Tap::write(const char *data, int len)
+{
+ int result = ::write(fd, data, len);
+ if (result < 0)
+ return false;
+
+ return true;
+}
+
int
main(int argc, char *argv[])
{
@@ -201,13 +328,16 @@ main(int argc, char *argv[])
bool listening = false;
char *device = NULL;
char *filter = NULL;
+ Ethernet *tap = NULL;
+ bool usetap = false;
char c;
int daemon = false;
- string host;
+ std::string host;
+ int devfd;
program = basename(argv[0]);
- while ((c = getopt(argc, argv, "b:df:lp:v")) != -1) {
+ while ((c = getopt(argc, argv, "b:df:lp:tv")) != -1) {
switch (c) {
case 'b':
bufsize = atoi(optarg);
@@ -224,6 +354,9 @@ main(int argc, char *argv[])
case 'p':
port = atoi(optarg);
break;
+ case 't':
+ usetap = true;
+ break;
case 'v':
verbose++;
break;
@@ -268,31 +401,14 @@ main(int argc, char *argv[])
host = *argv;
}
- char errbuf[PCAP_ERRBUF_SIZE];
- memset(errbuf, 0, sizeof errbuf);
- pcap_t *pcap = pcap_open_live(device, 1500, 1, -1, errbuf);
- if (pcap == NULL)
- panic("pcap_open_live failed: %s\n", errbuf);
-
- if (filter) {
- bpf_program program;
- bpf_u_int32 localnet, netmask;
- if (pcap_lookupnet(device, &localnet, &netmask, errbuf) == -1) {
- DPRINTF("pcap_lookupnet failed: %s\n", errbuf);
- netmask = 0xffffff00;
- }
-
- if (pcap_compile(pcap, &program, filter, 1, netmask) == -1)
- panic("pcap_compile failed, invalid filter:\n%s\n", filter);
-
- if (pcap_setfilter(pcap, &program) == -1)
- panic("pcap_setfilter failed\n");
+ if (usetap) {
+ if (filter)
+ panic("-f parameter not valid with a tap device!");
+ tap = new Tap(device);
+ } else {
+ tap = new PCap(device, filter);
}
- eth_t *ethernet = eth_open(device);
- if (!ethernet)
- panic("cannot open the ethernet device for writing\n");
-
pollfd pfds[3];
pfds[0].fd = Socket(true);
pfds[0].events = POLLIN;
@@ -303,7 +419,7 @@ main(int argc, char *argv[])
else
Connect(pfds[0].fd, host, port);
- pfds[1].fd = pcap_fileno(pcap);
+ pfds[1].fd = tap->getfd();
pfds[1].events = POLLIN;
pfds[1].revents = 0;
@@ -341,16 +457,16 @@ main(int argc, char *argv[])
listen_pfd->revents = 0;
}
+ DPRINTF("tap events: %x\n", tap_pfd->revents);
if (tap_pfd && tap_pfd->revents) {
if (tap_pfd->revents & POLLIN) {
- pcap_pkthdr hdr;
- const u_char *data = pcap_next(pcap, &hdr);
- if (data && client_pfd) {
- DPRINTF("Received packet from ethernet len=%d\n", hdr.len);
- DDUMP(data, hdr.len);
- u_int32_t len = htonl(hdr.len);
- write(client_pfd->fd, &len, sizeof(len));
- write(client_pfd->fd, data, hdr.len);
+ const char *data; int len;
+ if (tap->read(data, len) && client_pfd) {
+ DPRINTF("Received packet from ethernet len=%d\n", len);
+ DDUMP(data, len);
+ u_int32_t swaplen = htonl(len);
+ write(client_pfd->fd, &swaplen, sizeof(swaplen));
+ write(client_pfd->fd, data, len);
}
}
@@ -379,7 +495,7 @@ main(int argc, char *argv[])
while (data_len != 0 &&
buffer_offset >= data_len + sizeof(u_int32_t)) {
char *data = buffer + sizeof(u_int32_t);
- eth_send(ethernet, data, data_len);
+ tap->write(data, data_len);
DPRINTF("Sent packet to ethernet len = %d\n", data_len);
DDUMP(data, data_len);
@@ -412,8 +528,8 @@ main(int argc, char *argv[])
}
delete [] buffer;
- pcap_close(pcap);
- eth_close(ethernet);
+ delete tap;
+
if (listen_pfd)
close(listen_pfd->fd);