@@ -170,6 +170,69 @@ AS_IF(
]
)
+AC_ARG_WITH(
+ [signed-boot],
+ [AS_HELP_STRING([--with-signed-boot],
+ [build kernel signature checking support [default=yes]]
+ )],
+ [],
+ [with_signed_boot=yes]
+)
+
+AM_CONDITIONAL(
+ [WITH_SIGNED_BOOT],
+ [test "x$with_signed_boot" = "xyes"])
+
+AS_IF(
+ [test "x$with_signed_boot" = "xyes"],
+ [PKG_CHECK_MODULES(
+ [GPGME],
+ [gpgme >= 1.0.0],
+ [SAVE_LIBS="$LIBS" LIBS="$LIBS $gpgme_LIBS"
+ AC_CHECK_LIB(
+ [gpgme],
+ [gpgme_op_verify],
+ [],
+ [AC_MSG_FAILURE([--with-signed-boot was given but the test for gpgme failed.])]
+ )
+ LIBS="$SAVE_LIBS"
+ ],
+ [AM_PATH_GPGME([1.0.0], [SAVE_LIBS="$LIBS" LIBS="$LIBS $gpgme_LIBS"
+ AC_CHECK_LIB(
+ [gpgme],
+ [gpgme_op_verify],
+ [],
+ [AC_MSG_FAILURE([--with-signed-boot was given but the test for gpgme failed.])]
+ )
+ LIBS="$SAVE_LIBS"],
+ [AC_MSG_RESULT([$gpgme_PKG_ERRORS])
+ AC_MSG_FAILURE([ Consider adjusting PKG_CONFIG_PATH environment variable])
+ ])
+ ]
+ )]
+)
+
+AS_IF(
+ [test "x$with_signed_boot" = "xyes"],
+ [SAVE_CPPFLAGS="$CPPFLAGS" CPPFLAGS="$CPPFLAGS $gpgme_CFLAGS"
+ AC_CHECK_HEADERS(
+ [gpgme.h],
+ [],
+ [AC_MSG_FAILURE([ --with-signed-boot given but gpgme.h not found])]
+ )
+ CPPFLAGS="$SAVE_CPPFLAGS"
+ ]
+)
+
+AM_CONDITIONAL([WITH_GPGME], [test "x$with_signed_boot" = "xyes"])
+
+AC_ARG_VAR(
+ [lockdown_file],
+ [Location of authorized signature file [default = "/etc/pb-lockdown"]]
+)
+AS_IF([test "x$lockdown_file" = x], [lockdown_file="/etc/pb-lockdown"])
+AC_DEFINE_UNQUOTED(LOCKDOWN_FILE, "$lockdown_file", [Lockdown file location])
+
AC_ARG_ENABLE(
[busybox],
[AS_HELP_STRING(
@@ -58,7 +58,8 @@ discover_pb_discover_LDADD = \
discover/grub2/grub2-parser.ro \
discover/platform.ro \
$(core_lib) \
- $(UDEV_LIBS)
+ $(UDEV_LIBS) \
+ $(GPGME_LIBS)
discover_pb_discover_LDFLAGS = \
$(AM_LDFLAGS) \
@@ -26,27 +26,14 @@
#include "resource.h"
#include "platform.h"
+#include <security/gpg.h>
+
static const char *boot_hook_dir = PKG_SYSCONF_DIR "/boot.d";
enum {
BOOT_HOOK_EXIT_OK = 0,
BOOT_HOOK_EXIT_UPDATE = 2,
};
-struct boot_task {
- struct load_url_result *image;
- struct load_url_result *initrd;
- struct load_url_result *dtb;
- const char *local_image;
- const char *local_initrd;
- const char *local_dtb;
- const char *args;
- const char *boot_tty;
- boot_status_fn status_fn;
- void *status_arg;
- bool dry_run;
- bool cancelled;
-};
-
/**
* kexec_load - kexec load helper.
*/
@@ -59,20 +46,39 @@ static int kexec_load(struct boot_task *boot_task)
char *s_dtb = NULL;
char *s_args = NULL;
+ boot_task->local_initrd_override = NULL;
+ boot_task->local_dtb_override = NULL;
+ boot_task->local_image_override = NULL;
+
+ if ((result = gpg_validate_boot_files(boot_task))) {
+ if (result == KEXEC_LOAD_SIGNATURE_FAILURE) {
+ pb_log("%s: Aborting kexec due to"
+ " signature verification failure\n", __func__);
+ goto abort_kexec;
+ }
+ }
+
+ const char* local_initrd = (boot_task->local_initrd_override) ?
+ boot_task->local_initrd_override : boot_task->local_initrd;
+ const char* local_dtb = (boot_task->local_dtb_override) ?
+ boot_task->local_dtb_override : boot_task->local_dtb;
+ const char* local_image = (boot_task->local_image_override) ?
+ boot_task->local_image_override : boot_task->local_image;
+
p = argv;
*p++ = pb_system_apps.kexec; /* 1 */
*p++ = "-l"; /* 2 */
- if (boot_task->local_initrd) {
+ if (local_initrd) {
s_initrd = talloc_asprintf(boot_task, "--initrd=%s",
- boot_task->local_initrd);
+ local_initrd);
assert(s_initrd);
*p++ = s_initrd; /* 3 */
}
- if (boot_task->local_dtb) {
+ if (local_dtb) {
s_dtb = talloc_asprintf(boot_task, "--dtb=%s",
- boot_task->local_dtb);
+ local_dtb);
assert(s_dtb);
*p++ = s_dtb; /* 4 */
}
@@ -84,7 +90,7 @@ static int kexec_load(struct boot_task *boot_task)
*p++ = s_args; /* 5 */
}
- *p++ = boot_task->local_image; /* 6 */
+ *p++ = local_image; /* 6 */
*p++ = NULL; /* 7 */
result = process_run_simple_argv(boot_task, argv);
@@ -92,6 +98,9 @@ static int kexec_load(struct boot_task *boot_task)
if (result)
pb_log("%s: failed: (%d)\n", __func__, result);
+abort_kexec:
+ gpg_validate_boot_files_cleanup(boot_task);
+
return result;
}
@@ -378,23 +387,69 @@ static void boot_process(struct load_url_result *result, void *data)
check_load(task, "dtb", task->dtb))
goto no_load;
+ if (task->verify_signature) {
+ if (load_pending(task->image_signature) ||
+ load_pending(task->initrd_signature) ||
+ load_pending(task->dtb_signature) ||
+ load_pending(task->cmdline_signature))
+ return;
+
+ if (check_load(task, "kernel image signature",
+ task->image_signature) ||
+ check_load(task, "initrd signature",
+ task->initrd_signature) ||
+ check_load(task, "dtb signature",
+ task->dtb_signature) ||
+ check_load(task, "command line signature",
+ task->cmdline_signature))
+ goto no_sig_load;
+ }
+
/* we make a copy of the local paths, as the boot hooks might update
* and/or create these */
task->local_image = task->image ? task->image->local : NULL;
task->local_initrd = task->initrd ? task->initrd->local : NULL;
task->local_dtb = task->dtb ? task->dtb->local : NULL;
+ if (task->verify_signature) {
+ task->local_image_signature = task->image_signature ?
+ task->image_signature->local : NULL;
+ task->local_initrd_signature = task->initrd_signature ?
+ task->initrd_signature->local : NULL;
+ task->local_dtb_signature = task->dtb_signature ?
+ task->dtb_signature->local : NULL;
+ task->local_cmdline_signature = task->cmdline_signature ?
+ task->cmdline_signature->local : NULL;
+ }
+
run_boot_hooks(task);
update_status(task->status_fn, task->status_arg, BOOT_STATUS_INFO,
_("performing kexec_load"));
rc = kexec_load(task);
- if (rc) {
+ if (rc == KEXEC_LOAD_SIGNATURE_FAILURE) {
+ update_status(task->status_fn, task->status_arg,
+ BOOT_STATUS_ERROR,
+ _("signature verification failed"));
+ }
+ else if (rc == KEXEC_LOAD_SIG_SETUP_INVALID) {
+ update_status(task->status_fn, task->status_arg,
+ BOOT_STATUS_ERROR,
+ _("invalid signature configuration"));
+ }
+ else if (rc) {
update_status(task->status_fn, task->status_arg,
- BOOT_STATUS_ERROR, _("kexec load failed"));
+ BOOT_STATUS_ERROR,
+ _("kexec load failed"));
}
+no_sig_load:
+ cleanup_load(task->image_signature);
+ cleanup_load(task->initrd_signature);
+ cleanup_load(task->dtb_signature);
+ cleanup_load(task->cmdline_signature);
+
no_load:
cleanup_load(task->image);
cleanup_load(task->initrd);
@@ -435,6 +490,8 @@ struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
boot_status_fn status_fn, void *status_arg)
{
struct pb_url *image = NULL, *initrd = NULL, *dtb = NULL;
+ struct pb_url *image_sig = NULL, *initrd_sig = NULL, *dtb_sig = NULL,
+ *cmdline_sig = NULL;
const struct config *config;
struct boot_task *boot_task;
const char *boot_desc;
@@ -478,6 +535,8 @@ struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
boot_task->status_fn = status_fn;
boot_task->status_arg = status_arg;
+ boot_task->verify_signature = (lockdown_status() == PB_LOCKDOWN_SIGN);
+
if (cmd && cmd->boot_args) {
boot_task->args = talloc_strdup(boot_task, cmd->boot_args);
} else if (opt && opt->option->boot_args) {
@@ -494,11 +553,52 @@ struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
boot_task->boot_tty = config ? config->boot_tty : NULL;
}
+ if (boot_task->verify_signature) {
+ if (cmd && cmd->args_sig_file) {
+ cmdline_sig = pb_url_parse(opt, cmd->args_sig_file);
+ } else if (opt && opt->args_sig_file) {
+ cmdline_sig = opt->args_sig_file->url;
+ } else {
+ pb_log("%s: no command line signature file"
+ " specified\n", __func__);
+ update_status(status_fn, status_arg, BOOT_STATUS_INFO,
+ _("Boot failed: no command line"
+ " signature file specified"));
+ talloc_free(boot_task);
+ return NULL;
+ }
+ }
+
/* start async loads for boot resources */
rc = start_url_load(boot_task, "kernel image", image, &boot_task->image)
|| start_url_load(boot_task, "initrd", initrd, &boot_task->initrd)
|| start_url_load(boot_task, "dtb", dtb, &boot_task->dtb);
+ if (boot_task->verify_signature) {
+ /* Generate names of associated signature files and load */
+ if (image) {
+ image_sig = gpg_get_signature_url(ctx, image);
+ rc |= start_url_load(boot_task,
+ "kernel image signature", image_sig,
+ &boot_task->image_signature);
+ }
+ if (initrd) {
+ initrd_sig = gpg_get_signature_url(ctx, initrd);
+ rc |= start_url_load(boot_task, "initrd signature",
+ initrd_sig, &boot_task->initrd_signature);
+ }
+ if (dtb) {
+ dtb_sig = gpg_get_signature_url(ctx, dtb);
+ rc |= start_url_load(boot_task, "dtb signature",
+ dtb_sig, &boot_task->dtb_signature);
+ }
+
+ rc |= start_url_load(boot_task,
+ "kernel command line signature", cmdline_sig,
+ &boot_task->cmdline_signature);
+ }
+
+ /* If all URLs are local, we may be done. */
if (rc) {
/* Don't call boot_cancel() to preserve the status update */
boot_task->cancelled = true;
@@ -11,4 +11,37 @@ struct boot_task *boot(void *ctx, struct discover_boot_option *opt,
boot_status_fn status_fn, void *status_arg);
void boot_cancel(struct boot_task *task);
+
+struct boot_task {
+ struct load_url_result *image;
+ struct load_url_result *initrd;
+ struct load_url_result *dtb;
+ const char *local_image;
+ const char *local_initrd;
+ const char *local_dtb;
+ char *local_image_override;
+ char *local_initrd_override;
+ char *local_dtb_override;
+ const char *args;
+ const char *boot_tty;
+ boot_status_fn status_fn;
+ void *status_arg;
+ bool dry_run;
+ bool cancelled;
+ bool verify_signature;
+ struct load_url_result *image_signature;
+ struct load_url_result *initrd_signature;
+ struct load_url_result *dtb_signature;
+ struct load_url_result *cmdline_signature;
+ const char *local_image_signature;
+ const char *local_initrd_signature;
+ const char *local_dtb_signature;
+ const char *local_cmdline_signature;
+};
+
+enum {
+ KEXEC_LOAD_SIG_SETUP_INVALID = 253,
+ KEXEC_LOAD_SIGNATURE_FAILURE = 254,
+};
+
#endif /* _BOOT_H */
@@ -613,6 +613,7 @@ static bool __attribute__((used)) boot_option_is_resolved(
return resource_is_resolved(opt->boot_image) &&
resource_is_resolved(opt->initrd) &&
resource_is_resolved(opt->dtb) &&
+ resource_is_resolved(opt->args_sig_file) &&
resource_is_resolved(opt->icon);
}
@@ -638,6 +639,8 @@ static bool boot_option_resolve(struct discover_boot_option *opt,
return resource_resolve(opt->boot_image, "boot_image", opt, handler) &&
resource_resolve(opt->initrd, "initrd", opt, handler) &&
resource_resolve(opt->dtb, "dtb", opt, handler) &&
+ resource_resolve(opt->args_sig_file, "args_sig_file", opt,
+ handler) &&
resource_resolve(opt->icon, "icon", opt, handler);
}
@@ -652,6 +655,7 @@ static void boot_option_finalise(struct device_handler *handler,
assert(!opt->option->dtb_file);
assert(!opt->option->icon_file);
assert(!opt->option->device_id);
+ assert(!opt->option->args_sig_file);
if (opt->boot_image)
opt->option->boot_image_file = opt->boot_image->url->full;
@@ -661,6 +665,8 @@ static void boot_option_finalise(struct device_handler *handler,
opt->option->dtb_file = opt->dtb->url->full;
if (opt->icon)
opt->option->icon_file = opt->icon->url->full;
+ if (opt->args_sig_file)
+ opt->option->args_sig_file = opt->args_sig_file->url->full;
opt->option->device_id = opt->device->device->id;
@@ -48,6 +48,7 @@ struct discover_boot_option {
struct resource *boot_image;
struct resource *initrd;
struct resource *dtb;
+ struct resource *args_sig_file;
struct resource *icon;
};
@@ -6,7 +6,9 @@
#include <types/types.h>
#include <talloc/talloc.h>
#include <util/util.h>
+#include <url/url.h>
+#include "discover/resource.h"
#include "discover/parser.h"
#include "grub2.h"
@@ -69,6 +71,12 @@ static int builtin_linux(struct grub2_script *script,
opt->option->boot_args = talloc_asprintf_append(
opt->option->boot_args,
" %s", argv[i]);
+
+ char* args_sigfile_default = talloc_asprintf(opt,
+ "%s.cmdline.sig", argv[1]);
+ opt->args_sig_file = create_grub2_resource(opt, script->ctx->device,
+ root, args_sigfile_default);
+ talloc_free(args_sigfile_default);
return 0;
}
@@ -96,6 +96,12 @@ out_add:
d_opt->boot_image = create_devpath_resource(d_opt,
conf->dc->device, value);
+ char* args_sigfile_default = talloc_asprintf(d_opt,
+ "%s.cmdline.sig", value);
+ d_opt->args_sig_file = create_devpath_resource(d_opt,
+ conf->dc->device, args_sigfile_default);
+ talloc_free(args_sigfile_default);
+
if (root) {
opt->boot_args = talloc_asprintf(opt, "root=%s %s", root, args);
talloc_free(args);
@@ -166,6 +166,13 @@ static void pxe_process_pair(struct conf_context *ctx,
url = pxe_url_join(ctx->dc, ctx->dc->conf_url, value);
opt->boot_image = create_url_resource(opt, url);
+ char* args_sigfile_default = talloc_asprintf(opt,
+ "%s.cmdline.sig", value);
+ url = pxe_url_join(ctx->dc, ctx->dc->conf_url,
+ args_sigfile_default);
+ opt->args_sig_file = create_url_resource(opt, url);
+ talloc_free(args_sigfile_default);
+
} else if (streq(name, "INITRD")) {
url = pxe_url_join(ctx->dc, ctx->dc->conf_url, value);
opt->initrd = create_url_resource(opt, url);
@@ -82,7 +82,7 @@ static void user_event_print_event(struct event __attribute__((unused)) *event)
}
static struct resource *user_event_resource(struct discover_boot_option *opt,
- struct event *event)
+ struct event *event, bool gen_boot_args_sigfile)
{
const char *siaddr, *boot_file;
struct resource *res;
@@ -101,7 +101,16 @@ static struct resource *user_event_resource(struct discover_boot_option *opt,
return NULL;
}
- url_str = talloc_asprintf(opt, "%s%s/%s", "tftp://", siaddr, boot_file);
+ if (gen_boot_args_sigfile) {
+ char* args_sigfile_default = talloc_asprintf(opt,
+ "%s.cmdline.sig", boot_file);
+ url_str = talloc_asprintf(opt, "%s%s/%s", "tftp://", siaddr,
+ args_sigfile_default);
+ talloc_free(args_sigfile_default);
+ }
+ else
+ url_str = talloc_asprintf(opt, "%s%s/%s", "tftp://", siaddr,
+ boot_file);
url = pb_url_parse(opt, url_str);
talloc_free(url_str);
@@ -143,12 +152,13 @@ static int parse_user_event(struct discover_context *ctx, struct event *event)
opt->id = talloc_asprintf(opt, "%s#%s", dev->id, val);
opt->name = talloc_strdup(opt, val);
- d_opt->boot_image = user_event_resource(d_opt, event);
+ d_opt->boot_image = user_event_resource(d_opt, event, false);
if (!d_opt->boot_image) {
pb_log("%s: no boot image found for %s!\n", __func__,
opt->name);
goto fail_opt;
}
+ d_opt->args_sig_file = user_event_resource(d_opt, event, true);
val = event_get_param(event, "rootpath");
if (val) {
@@ -114,6 +114,13 @@ static void yaboot_finish(struct conf_context *conf)
/* populate the boot option from state data */
state->opt->boot_image = create_yaboot_devpath_resource(state,
conf, state->boot_image);
+
+ char* args_sigfile_default = talloc_asprintf(opt,
+ "%s.cmdline.sig", state->boot_image);
+ state->opt->args_sig_file = create_yaboot_devpath_resource(state,
+ conf, args_sigfile_default);
+ talloc_free(args_sigfile_default);
+
if (state->initrd) {
state->opt->initrd = create_yaboot_devpath_resource(state,
conf, state->initrd);
@@ -20,6 +20,13 @@ lib_libpbcore_la_CPPFLAGS = \
$(AM_CPPFLAGS) \
-DPREFIX='"$(prefix)"'
+if WITH_GPGME
+gpg_int_SOURCES = lib/security/gpg..h \
+ lib/security/gpg.c
+else
+gpg_int_SOURCES =
+endif
+
lib_libpbcore_la_SOURCES = \
lib/file/file.h \
lib/file/file.c \
@@ -50,7 +57,8 @@ lib_libpbcore_la_SOURCES = \
lib/util/util.c \
lib/util/util.h \
lib/flash/config.h \
- lib/flash/flash.h
+ lib/flash/flash.h \
+ $(gpg_int_SOURCES)
if ENABLE_MTD
lib_libpbcore_la_SOURCES += \
@@ -1,5 +1,6 @@
/*
* Copyright (C) 2013 Jeremy Kerr <jk@ozlabs.org>
+ * Copyright (C) 2016 Raptor Engineering, LLC
*
* 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
@@ -23,11 +24,87 @@
#include <sys/types.h>
#include <talloc/talloc.h>
+#include <log/log.h>
#include "file.h"
+#define MAX_FILENAME_SIZE 8192
+#define FILE_XFER_BUFFER_SIZE 8192
+
static const int max_file_size = 1024 * 1024;
+int copy_file_secure_dest(void *ctx,
+ const char *source_file, char **destination_file) {
+ int result = 0;
+ char template[] = "/tmp/petitbootXXXXXX";
+ char dest_filename[MAX_FILENAME_SIZE] = "";
+ FILE *source_handle = fopen(source_file, "r");
+ int destination_fd = mkstemp(template);
+ FILE *destination_handle = fdopen(destination_fd, "w");
+ if (!source_handle || !(destination_handle)) {
+ // handle open error
+ pb_log("%s: failed: unable to open source file '%s'\n",
+ __func__, source_file);
+ return -1;
+ }
+
+ size_t l1;
+ unsigned char *buffer;
+ buffer = talloc_array(ctx, unsigned char, FILE_XFER_BUFFER_SIZE);
+ if (!buffer) {
+ pb_log("%s: failed: unable to allocate file transfer buffer\n",
+ __func__);
+ return -1;
+ }
+
+ /* Copy data */
+ while ((l1 = fread(buffer, 1, sizeof buffer, source_handle)) > 0) {
+ size_t l2 = fwrite(buffer, 1, l1, destination_handle);
+ if (l2 < l1) {
+ if (ferror(destination_handle)) {
+ /* General error */
+ result = -1;
+ pb_log("%s: failed: unknown fault\n", __func__);
+ }
+ else {
+ /* No space on destination device */
+ result = -1;
+ pb_log("%s: failed: temporary storage full\n",
+ __func__);
+ }
+ break;
+ }
+ }
+
+ talloc_free(buffer);
+
+ if (result) {
+ dest_filename[0] = '\0';
+ }
+ else {
+ ssize_t r;
+ char readlink_buffer[MAX_FILENAME_SIZE];
+ snprintf(readlink_buffer, MAX_FILENAME_SIZE, "/proc/self/fd/%d",
+ destination_fd);
+ r = readlink(readlink_buffer, dest_filename,
+ MAX_FILENAME_SIZE);
+ if (r < 0) {
+ /* readlink failed */
+ result = -1;
+ pb_log("%s: failed: unable to obtain temporary filename"
+ "\n", __func__);
+ }
+ dest_filename[r] = '\0';
+ }
+
+ fclose(source_handle);
+ fclose(destination_handle);
+
+ *destination_file = talloc_strdup(ctx, dest_filename);
+
+ return result;
+}
+
int read_file(void *ctx, const char *filename, char **bufp, int *lenp)
{
struct stat statbuf;
@@ -1,5 +1,6 @@
/*
* Copyright (C) 2013 Jeremy Kerr <jk@ozlabs.org>
+ * Copyright (C) 2016 Raptor Engineering, LLC
*
* 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
@@ -17,6 +18,8 @@
#ifndef FILE_H
#define FILE_H
+int copy_file_secure_dest(void *ctx,
+ const char * source_file, char ** destination_file);
int read_file(void *ctx, const char *filename, char **bufp, int *lenp);
int replace_file(const char *filename, char *buf, int len);
@@ -37,6 +37,7 @@
* 4-byte len, initrd_file
* 4-byte len, dtb_file
* 4-byte len, boot_args
+ * 4-byte len, args_sig_file
*
* action = 0x2: device remove message
* payload:
@@ -49,6 +50,7 @@
* 4-byte len, initrd_file
* 4-byte len, dtb_file
* 4-byte len, boot_args
+ * 4-byte len, args_sig_file
*
*/
@@ -72,6 +74,7 @@ void pb_protocol_dump_device(const struct device *dev, const char *text,
fprintf(stream, "%s\t\tinit: %s\n", text, opt->initrd_file);
fprintf(stream, "%s\t\tdtb: %s\n", text, opt->dtb_file);
fprintf(stream, "%s\t\targs: %s\n", text, opt->boot_args);
+ fprintf(stream, "%s\t\tasig: %s\n", text, opt->args_sig_file);
}
}
@@ -197,6 +200,7 @@ int pb_protocol_boot_option_len(const struct boot_option *opt)
4 + optional_strlen(opt->initrd_file) +
4 + optional_strlen(opt->dtb_file) +
4 + optional_strlen(opt->boot_args) +
+ 4 + optional_strlen(opt->args_sig_file) +
sizeof(opt->is_default);
}
@@ -207,6 +211,7 @@ int pb_protocol_boot_len(const struct boot_command *boot)
4 + optional_strlen(boot->initrd_file) +
4 + optional_strlen(boot->dtb_file) +
4 + optional_strlen(boot->boot_args) +
+ 4 + optional_strlen(boot->args_sig_file) +
4 + optional_strlen(boot->tty);
}
@@ -360,6 +365,7 @@ int pb_protocol_serialise_boot_option(const struct boot_option *opt,
pos += pb_protocol_serialise_string(pos, opt->initrd_file);
pos += pb_protocol_serialise_string(pos, opt->dtb_file);
pos += pb_protocol_serialise_string(pos, opt->boot_args);
+ pos += pb_protocol_serialise_string(pos, opt->args_sig_file);
*(bool *)pos = opt->is_default;
pos += sizeof(bool);
@@ -380,6 +386,7 @@ int pb_protocol_serialise_boot_command(const struct boot_command *boot,
pos += pb_protocol_serialise_string(pos, boot->initrd_file);
pos += pb_protocol_serialise_string(pos, boot->dtb_file);
pos += pb_protocol_serialise_string(pos, boot->boot_args);
+ pos += pb_protocol_serialise_string(pos, boot->args_sig_file);
pos += pb_protocol_serialise_string(pos, boot->tty);
assert(pos <= buf + buf_len);
@@ -750,6 +757,9 @@ int pb_protocol_deserialise_boot_option(struct boot_option *opt,
if (read_string(opt, &pos, &len, &opt->boot_args))
goto out;
+ if (read_string(opt, &pos, &len, &opt->args_sig_file))
+ goto out;
+
if (len < sizeof(bool))
goto out;
opt->is_default = *(bool *)(pos);
@@ -785,6 +795,9 @@ int pb_protocol_deserialise_boot_command(struct boot_command *cmd,
if (read_string(cmd, &pos, &len, &cmd->boot_args))
goto out;
+ if (read_string(cmd, &pos, &len, &cmd->args_sig_file))
+ goto out;
+
if (read_string(cmd, &pos, &len, &cmd->tty))
goto out;
new file mode 100644
@@ -0,0 +1,328 @@
+/*
+ * Copyright (C) 2016 Raptor Engineering, LLC
+ *
+ * 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; 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#if defined(HAVE_CONFIG_H)
+#include "config.h"
+#endif
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <dirent.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/types.h>
+
+#include <log/log.h>
+#include <file/file.h>
+#include <talloc/talloc.h>
+#include <url/url.h>
+#include <util/util.h>
+#include <i18n/i18n.h>
+
+#include "gpg.h"
+
+struct pb_url * gpg_get_signature_url(void *ctx, struct pb_url *base_file)
+{
+ struct pb_url *signature_file = NULL;
+
+ signature_file = pb_url_copy(ctx, base_file);
+ talloc_free(signature_file->file);
+ signature_file->file = talloc_asprintf(signature_file,
+ "%s.sig", base_file->file);
+ talloc_free(signature_file->path);
+ signature_file->path = talloc_asprintf(signature_file,
+ "%s.sig", base_file->path);
+
+ return signature_file;
+}
+
+int verify_file_signature(const char *plaintext_filename,
+ const char *signature_filename, FILE *authorized_signatures_handle,
+ const char *keyring_path)
+{
+ int valid = 0;
+ gpgme_signature_t verification_signatures;
+ gpgme_verify_result_t verification_result;
+ gpgme_data_t plaintext_data;
+ gpgme_data_t signature_data;
+ gpgme_engine_info_t enginfo;
+ gpgme_ctx_t gpg_context;
+ gpgme_error_t err;
+
+ if (signature_filename == NULL)
+ return -1;
+
+ /* Initialize gpgme */
+ setlocale (LC_ALL, "");
+ gpgme_check_version(NULL);
+ gpgme_set_locale(NULL, LC_CTYPE, setlocale (LC_CTYPE, NULL));
+ err = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
+ if (err != GPG_ERR_NO_ERROR) {
+ pb_log("%s: OpenPGP support not available\n", __func__);
+ return -1;
+ }
+ err = gpgme_get_engine_info(&enginfo);
+ if (err != GPG_ERR_NO_ERROR) {
+ pb_log("%s: GPG engine failed to initialize\n", __func__);
+ return -1;
+ }
+ err = gpgme_new(&gpg_context);
+ if (err != GPG_ERR_NO_ERROR) {
+ pb_log("%s: GPG context could not be created\n", __func__);
+ return -1;
+ }
+ err = gpgme_set_protocol(gpg_context, GPGME_PROTOCOL_OpenPGP);
+ if (err != GPG_ERR_NO_ERROR) {
+ pb_log("%s: GPG protocol could not be set\n", __func__);
+ return -1;
+ }
+ if (keyring_path)
+ err = gpgme_ctx_set_engine_info (gpg_context,
+ GPGME_PROTOCOL_OpenPGP, enginfo->file_name,
+ keyring_path);
+ else
+ err = gpgme_ctx_set_engine_info (gpg_context,
+ GPGME_PROTOCOL_OpenPGP, enginfo->file_name,
+ enginfo->home_dir);
+ if (err != GPG_ERR_NO_ERROR) {
+ pb_log("%s: Could not set GPG engine information\n", __func__);
+ return -1;
+ }
+ err = gpgme_data_new_from_file(&plaintext_data, plaintext_filename, 1);
+ if (err != GPG_ERR_NO_ERROR) {
+ pb_log("%s: Could not create GPG plaintext data buffer"
+ " from file '%s'\n", __func__, plaintext_filename);
+ return -1;
+ }
+ err = gpgme_data_new_from_file(&signature_data, signature_filename, 1);
+ if (err != GPG_ERR_NO_ERROR) {
+ pb_log("%s: Could not create GPG signature data buffer"
+ " from file '%s'\n", __func__, signature_filename);
+ return -1;
+ }
+
+ /* Check signature */
+ err = gpgme_op_verify(gpg_context, signature_data, plaintext_data,
+ NULL);
+ if (err != GPG_ERR_NO_ERROR) {
+ pb_log("%s: Could not verify file using GPG signature '%s'\n",
+ __func__, signature_filename);
+ return -1;
+ }
+ verification_result = gpgme_op_verify_result(gpg_context);
+ verification_signatures = verification_result->signatures;
+ while (verification_signatures) {
+ if (verification_signatures->status != GPG_ERR_NO_ERROR) {
+ /* Signature verification failure */
+ pb_log("%s: Signature for key ID '%s' ('%s') invalid."
+ " Status: %08x\n", __func__,
+ verification_signatures->fpr,
+ signature_filename,
+ verification_signatures->status);
+ verification_signatures = verification_signatures->next;
+ continue;
+ }
+
+ /* Signature check passed with no error */
+ pb_log("%s: Good signature for key ID '%s' ('%s')\n",
+ __func__, verification_signatures->fpr,
+ signature_filename);
+ /* Verify fingerprint is present in
+ * authorized signatures file
+ */
+ char *auth_sig_line = NULL;
+ size_t auth_sig_len = 0;
+ ssize_t auth_sig_read;
+ rewind(authorized_signatures_handle);
+ while ((auth_sig_read = getline(&auth_sig_line,
+ &auth_sig_len,
+ authorized_signatures_handle)) != -1) {
+ auth_sig_len = strlen(auth_sig_line);
+ while ((auth_sig_line[auth_sig_len-1] == '\n')
+ || (auth_sig_line[auth_sig_len-1] == '\r'))
+ auth_sig_len--;
+ auth_sig_line[auth_sig_len] = '\0';
+ if (strcmp(auth_sig_line,
+ verification_signatures->fpr) == 0)
+ valid = 1;
+ }
+ free(auth_sig_line);
+ verification_signatures = verification_signatures->next;
+ }
+
+ /* Clean up */
+ gpgme_data_release(plaintext_data);
+ gpgme_data_release(signature_data);
+ gpgme_release(gpg_context);
+
+ if (!valid) {
+ pb_log("%s: Incorrect GPG signature\n", __func__);
+ return -1;
+ }
+
+ pb_log("%s: GPG signature '%s' for file '%s' verified\n",
+ __func__, signature_filename, plaintext_filename);
+
+ return 0;
+}
+
+int gpg_validate_boot_files(struct boot_task *boot_task) {
+ int result = 0;
+ char *kernel_filename = NULL;
+ char *initrd_filename = NULL;
+ char *dtb_filename = NULL;
+
+ FILE *authorized_signatures_handle = NULL;
+
+ char cmdline_template[] = "/tmp/petitbootXXXXXX";
+ int cmdline_fd = mkstemp(cmdline_template);
+ FILE *cmdline_handle = NULL;
+
+ const char* local_initrd_signature = (boot_task->verify_signature) ?
+ boot_task->local_initrd_signature : NULL;
+ const char* local_dtb_signature = (boot_task->verify_signature) ?
+ boot_task->local_dtb_signature : NULL;
+ const char* local_image_signature = (boot_task->verify_signature) ?
+ boot_task->local_image_signature : NULL;
+ const char* local_cmdline_signature = (boot_task->verify_signature) ?
+ boot_task->local_cmdline_signature : NULL;
+
+ if (!boot_task->verify_signature)
+ return result;
+
+ /* Load authorized signatures file */
+ authorized_signatures_handle = fopen(LOCKDOWN_FILE, "r");
+ if (!authorized_signatures_handle) {
+ pb_log("%s: unable to read lockdown file\n", __func__);
+ return KEXEC_LOAD_SIG_SETUP_INVALID;
+ }
+
+ /* Copy files to temporary directory for verification / boot */
+ result = copy_file_secure_dest(boot_task,
+ boot_task->local_image,
+ &kernel_filename);
+ if (result) {
+ pb_log("%s: image copy failed: (%d)\n",
+ __func__, result);
+ return result;
+ }
+ if (boot_task->local_initrd) {
+ result = copy_file_secure_dest(boot_task,
+ boot_task->local_initrd,
+ &initrd_filename);
+ if (result) {
+ pb_log("%s: initrd copy failed: (%d)\n",
+ __func__, result);
+ return result;
+ }
+ }
+ if (boot_task->local_dtb) {
+ result = copy_file_secure_dest(boot_task,
+ boot_task->local_dtb,
+ &dtb_filename);
+ if (result) {
+ pb_log("%s: dtb copy failed: (%d)\n",
+ __func__, result);
+ return result;
+ }
+ }
+ boot_task->local_image_override = talloc_strdup(boot_task,
+ kernel_filename);
+ if (boot_task->local_initrd)
+ boot_task->local_initrd_override = talloc_strdup(boot_task,
+ initrd_filename);
+ if (boot_task->local_dtb)
+ boot_task->local_dtb_override = talloc_strdup(boot_task,
+ dtb_filename);
+
+ /* Write command line to temporary file for verification */
+ if (cmdline_fd < 0) {
+ /* mkstemp failed */
+ pb_log("%s: failed: unable to create command line"
+ " temporary file for verification\n",
+ __func__);
+ result = -1;
+ }
+ else {
+ cmdline_handle = fdopen(cmdline_fd, "w");
+ }
+ if (!cmdline_handle) {
+ /* Failed to open file */
+ pb_log("%s: failed: unable to write command line"
+ " temporary file for verification\n",
+ __func__);
+ result = -1;
+ }
+ else {
+ fwrite(boot_task->args, sizeof(char),
+ strlen(boot_task->args), cmdline_handle);
+ fflush(cmdline_handle);
+ }
+
+ /* Check signatures */
+ if (verify_file_signature(kernel_filename,
+ local_image_signature,
+ authorized_signatures_handle, "/etc/gpg"))
+ result = KEXEC_LOAD_SIGNATURE_FAILURE;
+ if (verify_file_signature(cmdline_template,
+ local_cmdline_signature,
+ authorized_signatures_handle, "/etc/gpg"))
+ result = KEXEC_LOAD_SIGNATURE_FAILURE;
+ if (boot_task->local_initrd_signature)
+ if (verify_file_signature(initrd_filename,
+ local_initrd_signature,
+ authorized_signatures_handle, "/etc/gpg"))
+ result = KEXEC_LOAD_SIGNATURE_FAILURE;
+ if (boot_task->local_dtb_signature)
+ if (verify_file_signature(dtb_filename,
+ local_dtb_signature,
+ authorized_signatures_handle, "/etc/gpg"))
+ result = KEXEC_LOAD_SIGNATURE_FAILURE;
+
+ /* Clean up */
+ if (cmdline_handle) {
+ fclose(cmdline_handle);
+ unlink(cmdline_template);
+ }
+ fclose(authorized_signatures_handle);
+
+ return result;
+}
+
+void gpg_validate_boot_files_cleanup(struct boot_task *boot_task) {
+ if (boot_task->verify_signature) {
+ unlink(boot_task->local_image_override);
+ if (boot_task->local_initrd_override)
+ unlink(boot_task->local_initrd_override);
+ if (boot_task->local_dtb_override)
+ unlink(boot_task->local_dtb_override);
+
+ talloc_free(boot_task->local_image_override);
+ if (boot_task->local_initrd_override)
+ talloc_free(boot_task->local_initrd_override);
+ if (boot_task->local_dtb_override)
+ talloc_free(boot_task->local_dtb_override);
+ }
+}
+
+int lockdown_status() {
+ if (access(LOCKDOWN_FILE, F_OK) == -1)
+ return PB_LOCKDOWN_NONE;
+ else
+ return PB_LOCKDOWN_SIGN;
+}
\ No newline at end of file
new file mode 100644
@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2016 Raptor Engineering, LLC
+ *
+ * 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; 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _PB_GPG_H
+#define _PB_GPG_H
+
+#include <discover/boot.h>
+
+enum {
+ PB_LOCKDOWN_NONE = 0,
+ PB_LOCKDOWN_SIGN = 1,
+};
+
+#if defined(HAVE_LIBGPGME)
+#include <gpgme.h>
+#endif /* HAVE_LIBGPGME */
+
+int lockdown_status(void);
+
+struct pb_url * gpg_get_signature_url(void *ctx, struct pb_url *base_file);
+
+int verify_file_signature(const char *plaintext_filename,
+ const char *signature_filename, FILE *authorized_signatures_handle,
+ const char *keyring_path);
+
+int gpg_validate_boot_files(struct boot_task *boot_task);
+
+void gpg_validate_boot_files_cleanup(struct boot_task *boot_task);
+
+#if !defined(HAVE_LIBGPGME)
+
+int lockdown_status(void) { return PB_LOCKDOWN_NONE; }
+
+struct pb_url * gpg_get_signature_url(void *ctx, struct pb_url *base_file)
+ { return 0; }
+
+int verify_file_signature(const char *plaintext_filename,
+ const char *signature_filename, FILE *authorized_signatures_handle,
+ const char *keyring_path) { return -1; }
+
+int gpg_validate_boot_files(struct boot_task *boot_task) { return 0; }
+
+void gpg_validate_boot_files_cleanup(struct boot_task *boot_task) { }
+
+#endif /* HAVE_LIBGPGME */
+
+#endif /* _PB_GPG_H */
\ No newline at end of file
@@ -52,6 +52,7 @@ struct boot_option {
char *initrd_file;
char *dtb_file;
char *boot_args;
+ char *args_sig_file;
bool is_default;
struct list_item list;
@@ -65,6 +66,7 @@ struct boot_command {
char *initrd_file;
char *dtb_file;
char *boot_args;
+ char *args_sig_file;
char *tty;
};
@@ -312,6 +312,7 @@ static void create_boot_command(struct boot_command *command,
command->initrd_file = data->initrd;
command->dtb_file = data->dtb;
command->boot_args = data->args;
+ command->args_sig_file = data->args_sig_file;
command->tty = ttyname(STDIN_FILENO);
}
@@ -11,6 +11,7 @@ struct pb_boot_data {
char *initrd;
char *dtb;
char *args;
+ char *args_sig_file;
};
/**
@@ -63,6 +63,8 @@ struct boot_editor {
struct nc_widget_textbox *dtb_f;
struct nc_widget_label *args_l;
struct nc_widget_textbox *args_f;
+ struct nc_widget_label *args_sig_file_l;
+ struct nc_widget_textbox *args_sig_file_f;
struct nc_widget_button *ok_b;
struct nc_widget_button *help_b;
struct nc_widget_button *cancel_b;
@@ -73,6 +75,9 @@ struct boot_editor {
char *initrd;
char *dtb;
char *args;
+ char *args_sig_file;
+
+ bool use_signature_files;
};
extern const struct help_text boot_editor_help_text;
@@ -198,6 +203,15 @@ static struct pb_boot_data *boot_editor_prepare_data(
s = widget_textbox_get_value(boot_editor->widgets.args_f);
bd->args = *s ? talloc_strdup(bd, s) : NULL;
+ if (boot_editor->use_signature_files) {
+ s = widget_textbox_get_value(
+ boot_editor->widgets.args_sig_file_f);
+ bd->args_sig_file = conditional_prefix(bd, prefix, s);
+ }
+ else {
+ bd->args_sig_file = NULL;
+ }
+
return bd;
}
@@ -323,6 +337,12 @@ static void boot_editor_layout_widgets(struct boot_editor *boot_editor)
y += layout_pair(boot_editor, y, boot_editor->widgets.args_l,
boot_editor->widgets.args_f);
+ if (boot_editor->use_signature_files) {
+ y += layout_pair(boot_editor, y,
+ boot_editor->widgets.args_sig_file_l,
+ boot_editor->widgets.args_sig_file_f);
+ }
+
y++;
widget_move(widget_button_base(boot_editor->widgets.ok_b), y,
@@ -445,6 +465,11 @@ static void boot_editor_find_device(struct boot_editor *boot_editor,
if (bd->dtb && !path_on_device(bd_info, bd->dtb))
return;
+ if (boot_editor->use_signature_files)
+ if (bd->args_sig_file && !path_on_device(bd_info,
+ bd->args_sig_file))
+ return;
+
/* ok, we match; preselect the device option, and remove the common
* prefix */
boot_editor->selected_device = bd_info->name;
@@ -454,6 +479,9 @@ static void boot_editor_find_device(struct boot_editor *boot_editor,
boot_editor->initrd += len;
if (boot_editor->dtb)
boot_editor->dtb += len;
+ if (boot_editor->use_signature_files)
+ if (boot_editor->args_sig_file)
+ boot_editor->args_sig_file += len;
}
static void boot_editor_setup_widgets(struct boot_editor *boot_editor,
@@ -501,6 +529,17 @@ static void boot_editor_setup_widgets(struct boot_editor *boot_editor,
boot_editor->widgets.args_f = widget_new_textbox(set, 0, 0,
field_size, boot_editor->args);
+ if (boot_editor->use_signature_files) {
+ boot_editor->widgets.args_sig_file_l = widget_new_label(set,
+ 0, 0, _("Argument signature file:"));
+ boot_editor->widgets.args_sig_file_f = widget_new_textbox(set,
+ 0, 0, field_size, boot_editor->args_sig_file);
+ }
+ else {
+ boot_editor->widgets.args_sig_file_l = NULL;
+ boot_editor->widgets.args_sig_file_f = NULL;
+ }
+
boot_editor->widgets.ok_b = widget_new_button(set, 0, 0, 10,
_("OK"), ok_click, boot_editor);
boot_editor->widgets.help_b = widget_new_button(set, 0, 0, 10,
@@ -553,6 +592,15 @@ struct boot_editor *boot_editor_init(struct cui *cui,
if (!boot_editor)
return NULL;
+#if defined(HAVE_LIBGPGME)
+ if (access(LOCKDOWN_FILE, F_OK) == -1)
+ boot_editor->use_signature_files = false;
+ else
+ boot_editor->use_signature_files = true;
+#else
+ boot_editor->use_signature_files = false;
+#endif
+
talloc_set_destructor(boot_editor, boot_editor_destructor);
boot_editor->cui = cui;
boot_editor->item = item;
@@ -563,9 +611,10 @@ struct boot_editor *boot_editor_init(struct cui *cui,
int ncols1 = strncols(_("Device tree:"));
int ncols2 = strncols(_("Boot arguments:"));
+ int ncols3 = strncols(_("Argument signature file:"));
boot_editor->label_x = 1;
- boot_editor->field_x = 2 + max(ncols1, ncols2);
+ boot_editor->field_x = 2 + max(max(ncols1, ncols2), ncols3);
nc_scr_init(&boot_editor->scr, pb_boot_editor_sig, 0,
cui, boot_editor_process_key,
@@ -584,10 +633,15 @@ struct boot_editor *boot_editor_init(struct cui *cui,
boot_editor->initrd = bd->initrd;
boot_editor->dtb = bd->dtb;
boot_editor->args = bd->args;
+ if (boot_editor->use_signature_files)
+ boot_editor->args_sig_file = bd->args_sig_file;
+ else
+ boot_editor->args_sig_file = talloc_strdup(bd, "");
boot_editor_find_device(boot_editor, bd, sysinfo);
} else {
boot_editor->image = boot_editor->initrd =
- boot_editor->dtb = boot_editor->args = "";
+ boot_editor->dtb = boot_editor->args =
+ boot_editor->args_sig_file = "";
}
boot_editor->pad = newpad(
@@ -543,6 +543,7 @@ static int cui_boot_option_add(struct device *dev, struct boot_option *opt,
cod->bd->initrd = talloc_strdup(cod->bd, opt->initrd_file);
cod->bd->dtb = talloc_strdup(cod->bd, opt->dtb_file);
cod->bd->args = talloc_strdup(cod->bd, opt->boot_args);
+ cod->bd->args_sig_file = talloc_strdup(cod->bd, opt->args_sig_file);
/* This disconnects items array from menu. */
result = set_menu_items(cui->main->ncm, NULL);
@@ -566,6 +567,7 @@ static int cui_boot_option_add(struct device *dev, struct boot_option *opt,
pb_log(" image '%s'\n", cod->bd->image);
pb_log(" initrd '%s'\n", cod->bd->initrd);
pb_log(" args '%s'\n", cod->bd->args);
+ pb_log(" argsig '%s'\n", cod->bd->args_sig_file);
/* Re-attach the items array. */
result = set_menu_items(cui->main->ncm, cui->main->items);
kernels and related blobs This can be used to implement a form of organization-controlled secure boot, whereby kernels may be loaded from a variety of sources but they will only boot if a valid signature file is found for each component, and only if the signature is listed in the /etc/pb-lockdown file. Signed-off-by: Timothy Pearson <tpearson@raptorengineering.com> --- configure.ac | 63 ++++++++ discover/Makefile.am | 3 +- discover/boot.c | 144 ++++++++++++++++--- discover/boot.h | 33 +++++ discover/device-handler.c | 6 + discover/device-handler.h | 1 + discover/grub2/builtins.c | 8 ++ discover/kboot-parser.c | 6 + discover/pxe-parser.c | 7 + discover/user-event.c | 16 ++- discover/yaboot-parser.c | 7 + lib/Makefile.am | 10 +- lib/file/file.c | 77 ++++++++++ lib/file/file.h | 3 + lib/pb-protocol/pb-protocol.c | 13 ++ lib/security/gpg.c | 328 ++++++++++++++++++++++++++++++++++++++++++ lib/security/gpg.h | 61 ++++++++ lib/types/types.h | 2 + ui/common/discover-client.c | 1 + ui/common/discover-client.h | 1 + ui/ncurses/nc-boot-editor.c | 58 +++++++- ui/ncurses/nc-cui.c | 2 + 22 files changed, 821 insertions(+), 29 deletions(-) create mode 100644 lib/security/gpg.c create mode 100644 lib/security/gpg.h