--- /dev/null
+/******************************************************************************
+ * tools/vmtrace.c
+ *
+ * Demonstrative tool for collecting Intel Processor Trace data from Xen.
+ * Could be used to externally monitor a given vCPU in given DomU.
+ *
+ * Copyright (C) 2020 by CERT Polska - NASK PIB
+ *
+ * Authors: Michał Leszczyński, michal.leszczynski@cert.pl
+ * Date: June, 2020
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; under version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <err.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+
+#include <xenctrl.h>
+#include <xenforeignmemory.h>
+
+#define MSR_RTIT_CTL 0x00000570
+#define RTIT_CTL_OS (1 << 2)
+#define RTIT_CTL_USR (1 << 3)
+#define RTIT_CTL_BRANCH_EN (1 << 13)
+
+static xc_interface *xch;
+static xenforeignmemory_handle *fh;
+static uint32_t domid, vcpu;
+static size_t size;
+static char *buf;
+
+static sig_atomic_t interrupted;
+static void int_handler(int signum)
+{
+ interrupted = 1;
+}
+
+static int get_more_data(void)
+{
+ static uint64_t last_pos;
+ uint64_t pos;
+
+ if ( xc_vmtrace_output_position(xch, domid, vcpu, &pos) )
+ {
+ perror("xc_vmtrace_output_position()");
+ return -1;
+ }
+
+ if ( pos > last_pos )
+ fwrite(buf + last_pos, pos - last_pos, 1, stdout);
+ else if ( pos < last_pos )
+ {
+ /* buffer wrapped */
+ fwrite(buf + last_pos, size - last_pos, 1, stdout);
+ fwrite(buf, pos, 1, stdout);
+ }
+
+ last_pos = pos;
+ return 0;
+}
+
+int main(int argc, char **argv)
+{
+ int rc, exit = 1;
+ xenforeignmemory_resource_handle *fres = NULL;
+
+ if ( signal(SIGINT, int_handler) == SIG_ERR )
+ err(1, "Failed to register signal handler\n");
+
+ if ( argc != 3 )
+ {
+ fprintf(stderr, "Usage: %s <domid> <vcpu_id>\n", argv[0]);
+ fprintf(stderr, "It's recommended to redirect thisprogram's output to file\n");
+ fprintf(stderr, "or to pipe it's output to xxd or other program.\n");
+ return 1;
+ }
+
+ domid = atoi(argv[1]);
+ vcpu = atoi(argv[2]);
+
+ xch = xc_interface_open(NULL, NULL, 0);
+ fh = xenforeignmemory_open(NULL, 0);
+
+ if ( !xch )
+ err(1, "xc_interface_open()");
+ if ( !fh )
+ err(1, "xenforeignmemory_open()");
+
+ rc = xenforeignmemory_resource_size(
+ fh, domid, XENMEM_resource_vmtrace_buf, vcpu, &size);
+ if ( rc )
+ err(1, "xenforeignmemory_resource_size()");
+
+ fres = xenforeignmemory_map_resource(
+ fh, domid, XENMEM_resource_vmtrace_buf, vcpu,
+ 0, size >> XC_PAGE_SHIFT, (void **)&buf, PROT_READ, 0);
+ if ( !fres )
+ err(1, "xenforeignmemory_map_resource()");
+
+ if ( xc_vmtrace_set_option(
+ xch, domid, vcpu, MSR_RTIT_CTL,
+ RTIT_CTL_BRANCH_EN | RTIT_CTL_USR | RTIT_CTL_OS) )
+ {
+ perror("xc_vmtrace_set_option()");
+ goto out;
+ }
+
+ if ( xc_vmtrace_enable(xch, domid, vcpu) )
+ {
+ perror("xc_vmtrace_enable()");
+ goto out;
+ }
+
+ while ( !interrupted )
+ {
+ xc_dominfo_t dominfo;
+
+ if ( get_more_data() )
+ goto out;
+
+ usleep(1000 * 100);
+
+ if ( xc_domain_getinfo(xch, domid, 1, &dominfo) != 1 ||
+ dominfo.domid != domid || dominfo.shutdown )
+ {
+ if ( get_more_data() )
+ goto out;
+ break;
+ }
+ }
+
+ exit = 0;
+
+ out:
+ if ( xc_vmtrace_disable(xch, domid, vcpu) )
+ perror("xc_vmtrace_disable()");
+
+ if ( fres && xenforeignmemory_unmap_resource(fh, fres) )
+ perror("xenforeignmemory_unmap_resource()");
+
+ return exit;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
projects / xen.git / commitdiff