| Message ID | 8bc5959478d6ba1c1873615b53628094da578688.1594150543.git.michal.leszczynski@cert.pl (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Implement support for external IPT monitoring | expand |
On Tue, Jul 07, 2020 at 09:39:50PM +0200, Michał Leszczyński wrote: > From: Michal Leszczynski <michal.leszczynski@cert.pl> > > Add an demonstration tool that uses xc_vmtrace_* calls in order ^ a > to manage external IPT monitoring for DomU. > > Signed-off-by: Michal Leszczynski <michal.leszczynski@cert.pl> > --- > tools/proctrace/Makefile | 45 +++++++++ > tools/proctrace/proctrace.c | 179 ++++++++++++++++++++++++++++++++++++ > 2 files changed, 224 insertions(+) > create mode 100644 tools/proctrace/Makefile > create mode 100644 tools/proctrace/proctrace.c > > diff --git a/tools/proctrace/Makefile b/tools/proctrace/Makefile > new file mode 100644 > index 0000000000..9c135229b9 > --- /dev/null > +++ b/tools/proctrace/Makefile > @@ -0,0 +1,45 @@ > +# Copyright (C) CERT Polska - NASK PIB > +# Author: Michał Leszczyński <michal.leszczynski@cert.pl> > +# > +# 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. > + > +XEN_ROOT=$(CURDIR)/../.. > +include $(XEN_ROOT)/tools/Rules.mk > + > +CFLAGS += -Werror > +CFLAGS += $(CFLAGS_libxenevtchn) > +CFLAGS += $(CFLAGS_libxenctrl) > +LDLIBS += $(LDLIBS_libxenctrl) > +LDLIBS += $(LDLIBS_libxenevtchn) > +LDLIBS += $(LDLIBS_libxenforeignmemory) > + > +.PHONY: all > +all: build > + > +.PHONY: build > +build: proctrace > + > +.PHONY: install > +install: build > + $(INSTALL_DIR) $(DESTDIR)$(sbindir) > + $(INSTALL_PROG) proctrace $(DESTDIR)$(sbindir)/proctrace > + > +.PHONY: uninstall > +uninstall: > + rm -f $(DESTDIR)$(sbindir)/proctrace > + > +.PHONY: clean > +clean: > + $(RM) -f proctrace $(DEPS_RM) > + > +.PHONY: distclean > +distclean: clean > + > +-include $(DEPS_INCLUDE) > diff --git a/tools/proctrace/proctrace.c b/tools/proctrace/proctrace.c > new file mode 100644 > index 0000000000..3c1ccccee8 > --- /dev/null > +++ b/tools/proctrace/proctrace.c > @@ -0,0 +1,179 @@ > +/****************************************************************************** > + * tools/proctrace.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 <stdlib.h> > +#include <stdio.h> > +#include <sys/mman.h> > +#include <signal.h> > +#include <errno.h> > + > +#include <xenctrl.h> > +#include <xen/xen.h> > +#include <xenforeignmemory.h> > + > +volatile int interrupted = 0; > +volatile int domain_down = 0; No need for the initialization, globals are already initialized to 0. > +void term_handler(int signum) { > + interrupted = 1; > +} > + > +int main(int argc, char* argv[]) { > + xc_interface *xc; > + uint32_t domid; > + uint32_t vcpu_id; > + uint64_t size; > + > + int rc = -1; > + uint8_t *buf = NULL; > + uint64_t last_offset = 0; > + > + xenforeignmemory_handle *fmem; > + xenforeignmemory_resource_handle *fres; > + > + if (signal(SIGINT, term_handler) == SIG_ERR) > + { > + fprintf(stderr, "Failed to register signal handler\n"); > + return 1; > + } > + > + if (argc != 3) { > + fprintf(stderr, "Usage: %s <domid> <vcpu_id>\n", argv[0]); > + fprintf(stderr, "It's recommended to redirect this" > + "program'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_id = atoi(argv[2]); > + > + xc = xc_interface_open(0, 0, 0); > + > + fmem = xenforeignmemory_open(0, 0); I think you also need to test that fmem is set? (like you do for xc). > + > + if (!xc) { > + fprintf(stderr, "Failed to open xc interface\n"); > + return 1; > + } > + > + rc = xc_vmtrace_pt_enable(xc, domid, vcpu_id); > + > + if (rc) { > + fprintf(stderr, "Failed to call xc_vmtrace_pt_enable\n"); > + return 1; > + } > + > + rc = xc_vmtrace_pt_get_offset(xc, domid, vcpu_id, NULL, &size); > + > + if (rc) { > + fprintf(stderr, "Failed to get trace buffer size\n"); > + return 1; > + } > + > + fres = xenforeignmemory_map_resource( > + fmem, domid, XENMEM_resource_vmtrace_buf, > + /* vcpu: */ vcpu_id, > + /* frame: */ 0, > + /* num_frames: */ size >> XC_PAGE_SHIFT, > + (void **)&buf, > + PROT_READ, 0); > + > + if (!buf) { > + fprintf(stderr, "Failed to map trace buffer\n"); > + return 1; > + } > + > + while (!interrupted) { > + uint64_t offset; > + rc = xc_vmtrace_pt_get_offset(xc, domid, vcpu_id, &offset, NULL); > + > + if (rc == ENODATA) { > + interrupted = 1; > + domain_down = 1; > + } else if (rc) { Hard tab. > + fprintf(stderr, "Failed to call xc_vmtrace_pt_get_offset\n"); Should you try to disable vmtrace here before exiting? > + return 1; > + } > + > + if (offset > last_offset) > + { > + fwrite(buf + last_offset, offset - last_offset, 1, stdout); > + } > + else if (offset < last_offset) > + { > + // buffer wrapped I know this is a test utility, but I would prefer if you could use the C comment style /* */. > + fwrite(buf + last_offset, size - last_offset, 1, stdout); > + fwrite(buf, offset, 1, stdout); > + } > + > + last_offset = offset; > + usleep(1000 * 100); > + } > + > + rc = xenforeignmemory_unmap_resource(fmem, fres); > + > + if (rc) { > + fprintf(stderr, "Failed to unmap resource\n"); > + return 1; > + } > + > + rc = xenforeignmemory_close(fmem); > + > + if (rc) { > + fprintf(stderr, "Failed to close fmem\n"); > + return 1; > + } > + > + /* > + * Don't try to disable PT if the domain is already dying. > + */ > + if (!domain_down) { > + rc = xc_vmtrace_pt_disable(xc, domid, vcpu_id); I'm not sure you can assume a domain is dying just because xc_vmtrace_pt_get_offset has returned ENODATA. Is there any harm in unconditionally attempting to disable vmtrace? Thanks.
diff --git a/tools/proctrace/Makefile b/tools/proctrace/Makefile new file mode 100644 index 0000000000..9c135229b9 --- /dev/null +++ b/tools/proctrace/Makefile @@ -0,0 +1,45 @@ +# Copyright (C) CERT Polska - NASK PIB +# Author: Michał Leszczyński <michal.leszczynski@cert.pl> +# +# 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. + +XEN_ROOT=$(CURDIR)/../.. +include $(XEN_ROOT)/tools/Rules.mk + +CFLAGS += -Werror +CFLAGS += $(CFLAGS_libxenevtchn) +CFLAGS += $(CFLAGS_libxenctrl) +LDLIBS += $(LDLIBS_libxenctrl) +LDLIBS += $(LDLIBS_libxenevtchn) +LDLIBS += $(LDLIBS_libxenforeignmemory) + +.PHONY: all +all: build + +.PHONY: build +build: proctrace + +.PHONY: install +install: build + $(INSTALL_DIR) $(DESTDIR)$(sbindir) + $(INSTALL_PROG) proctrace $(DESTDIR)$(sbindir)/proctrace + +.PHONY: uninstall +uninstall: + rm -f $(DESTDIR)$(sbindir)/proctrace + +.PHONY: clean +clean: + $(RM) -f proctrace $(DEPS_RM) + +.PHONY: distclean +distclean: clean + +-include $(DEPS_INCLUDE) diff --git a/tools/proctrace/proctrace.c b/tools/proctrace/proctrace.c new file mode 100644 index 0000000000..3c1ccccee8 --- /dev/null +++ b/tools/proctrace/proctrace.c @@ -0,0 +1,179 @@ +/****************************************************************************** + * tools/proctrace.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 <stdlib.h> +#include <stdio.h> +#include <sys/mman.h> +#include <signal.h> +#include <errno.h> + +#include <xenctrl.h> +#include <xen/xen.h> +#include <xenforeignmemory.h> + +volatile int interrupted = 0; +volatile int domain_down = 0; + +void term_handler(int signum) { + interrupted = 1; +} + +int main(int argc, char* argv[]) { + xc_interface *xc; + uint32_t domid; + uint32_t vcpu_id; + uint64_t size; + + int rc = -1; + uint8_t *buf = NULL; + uint64_t last_offset = 0; + + xenforeignmemory_handle *fmem; + xenforeignmemory_resource_handle *fres; + + if (signal(SIGINT, term_handler) == SIG_ERR) + { + fprintf(stderr, "Failed to register signal handler\n"); + return 1; + } + + if (argc != 3) { + fprintf(stderr, "Usage: %s <domid> <vcpu_id>\n", argv[0]); + fprintf(stderr, "It's recommended to redirect this" + "program'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_id = atoi(argv[2]); + + xc = xc_interface_open(0, 0, 0); + + fmem = xenforeignmemory_open(0, 0); + + if (!xc) { + fprintf(stderr, "Failed to open xc interface\n"); + return 1; + } + + rc = xc_vmtrace_pt_enable(xc, domid, vcpu_id); + + if (rc) { + fprintf(stderr, "Failed to call xc_vmtrace_pt_enable\n"); + return 1; + } + + rc = xc_vmtrace_pt_get_offset(xc, domid, vcpu_id, NULL, &size); + + if (rc) { + fprintf(stderr, "Failed to get trace buffer size\n"); + return 1; + } + + fres = xenforeignmemory_map_resource( + fmem, domid, XENMEM_resource_vmtrace_buf, + /* vcpu: */ vcpu_id, + /* frame: */ 0, + /* num_frames: */ size >> XC_PAGE_SHIFT, + (void **)&buf, + PROT_READ, 0); + + if (!buf) { + fprintf(stderr, "Failed to map trace buffer\n"); + return 1; + } + + while (!interrupted) { + uint64_t offset; + rc = xc_vmtrace_pt_get_offset(xc, domid, vcpu_id, &offset, NULL); + + if (rc == ENODATA) { + interrupted = 1; + domain_down = 1; + } else if (rc) { + fprintf(stderr, "Failed to call xc_vmtrace_pt_get_offset\n"); + return 1; + } + + if (offset > last_offset) + { + fwrite(buf + last_offset, offset - last_offset, 1, stdout); + } + else if (offset < last_offset) + { + // buffer wrapped + fwrite(buf + last_offset, size - last_offset, 1, stdout); + fwrite(buf, offset, 1, stdout); + } + + last_offset = offset; + usleep(1000 * 100); + } + + rc = xenforeignmemory_unmap_resource(fmem, fres); + + if (rc) { + fprintf(stderr, "Failed to unmap resource\n"); + return 1; + } + + rc = xenforeignmemory_close(fmem); + + if (rc) { + fprintf(stderr, "Failed to close fmem\n"); + return 1; + } + + /* + * Don't try to disable PT if the domain is already dying. + */ + if (!domain_down) { + rc = xc_vmtrace_pt_disable(xc, domid, vcpu_id); + + if (rc) { + fprintf(stderr, "Failed to call xc_vmtrace_pt_disable\n"); + return 1; + } + } + + rc = xc_interface_close(xc); + + if (rc) { + fprintf(stderr, "Failed to close xc interface\n"); + return 1; + } + + return 0; +} + +/* + * Local variables: + * mode: C + * c-file-style: "BSD" + * c-basic-offset: 4 + * tab-width: 4 + * indent-tabs-mode: nil + * End: + */