Merge pull request #25608 from poettering/dissect-moar

dissect: add dissection policies

5 files changed, 179 insertions, 0 deletions

diff --git a/src/analyze/analyze-image-policy.c b/src/analyze/analyze-image-policy.c
new file mode 100644
index 0000000000..026216629c
--- /dev/null
+++ b/src/analyze/analyze-image-policy.c
@@ -0,0 +1,154 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "analyze-image-policy.h"
+#include "analyze.h"
+#include "format-table.h"
+#include "terminal-util.h"
+
+static int table_add_designator_line(Table *table, PartitionDesignator d, PartitionPolicyFlags f) {
+        _cleanup_free_ char *q = NULL;
+        const char *color;
+        int r;
+
+        assert(table);
+        assert(f >= 0);
+
+        if (partition_policy_flags_to_string(f & _PARTITION_POLICY_USE_MASK, /* simplify= */ true, &q) < 0)
+                return log_oom();
+
+        color = (f & _PARTITION_POLICY_USE_MASK) == PARTITION_POLICY_IGNORE ? ansi_grey() :
+                ((f & (PARTITION_POLICY_UNPROTECTED|PARTITION_POLICY_ENCRYPTED|PARTITION_POLICY_VERITY|PARTITION_POLICY_SIGNED|PARTITION_POLICY_ABSENT)) ==
+                   (PARTITION_POLICY_UNPROTECTED|PARTITION_POLICY_ENCRYPTED|PARTITION_POLICY_VERITY|PARTITION_POLICY_SIGNED|PARTITION_POLICY_ABSENT)) ? ansi_highlight_yellow() :
+                (f & _PARTITION_POLICY_USE_MASK) == PARTITION_POLICY_ABSENT ? ansi_highlight_red() :
+                !(f & PARTITION_POLICY_UNPROTECTED) ? ansi_highlight_green() : NULL;
+
+        if (d < 0)
+                r = table_add_many(table,
+                                   TABLE_STRING, "default",
+                                   TABLE_SET_COLOR, ansi_highlight_green(),
+                                   TABLE_STRING, q,
+                                   TABLE_SET_COLOR, color);
+        else
+                r = table_add_many(table,
+                                   TABLE_STRING, partition_designator_to_string(d),
+                                   TABLE_SET_COLOR, ansi_normal(),
+                                   TABLE_STRING, q,
+                                   TABLE_SET_COLOR, color);
+        if (r < 0)
+                return table_log_add_error(r);
+
+        switch (f & _PARTITION_POLICY_READ_ONLY_MASK) {
+
+        case PARTITION_POLICY_READ_ONLY_ON:
+                r = table_add_many(table, TABLE_BOOLEAN, true);
+                break;
+
+        case PARTITION_POLICY_READ_ONLY_OFF:
+                r = table_add_many(table, TABLE_BOOLEAN, false);
+                break;
+
+        default:
+                r = table_add_many(table, TABLE_EMPTY);
+                break;
+        }
+        if (r < 0)
+                return table_log_add_error(r);
+
+        switch (f & _PARTITION_POLICY_GROWFS_MASK) {
+
+        case PARTITION_POLICY_GROWFS_ON:
+                r = table_add_many(table, TABLE_BOOLEAN, true);
+                break;
+
+        case PARTITION_POLICY_GROWFS_OFF:
+                r = table_add_many(table, TABLE_BOOLEAN, false);
+                break;
+
+        default:
+                r = table_add_many(table, TABLE_EMPTY);
+                break;
+        }
+
+        if (r < 0)
+                return table_log_add_error(r);
+
+        return 0;
+}
+
+int verb_image_policy(int argc, char *argv[], void *userdata) {
+        int r;
+
+        for (int i = 1; i < argc; i++) {
+                _cleanup_(table_unrefp) Table *table = NULL;
+                _cleanup_(image_policy_freep) ImagePolicy *pbuf = NULL;
+                _cleanup_free_ char *as_string = NULL, *as_string_simplified = NULL;
+                const ImagePolicy *p;
+
+                /* NB: The magic '@' strings are not officially documented for now, since we might change
+                 * around defaults (and in particular where precisely to reuse policy). We should document
+                 * them once the dust has settled a bit. For now it's just useful for debugging and
+                 * introspect our own defaults without guaranteeing API safety. */
+                if (streq(argv[i], "@sysext"))
+                        p = &image_policy_sysext;
+                else if (streq(argv[i], "@sysext-strict"))
+                        p = &image_policy_sysext_strict;
+                else if (streq(argv[i], "@container"))
+                        p = &image_policy_container;
+                else if (streq(argv[i], "@service"))
+                        p = &image_policy_service;
+                else if (streq(argv[i], "@host"))
+                        p = &image_policy_host;
+                else {
+                        r = image_policy_from_string(argv[i], &pbuf);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to parse image policy '%s': %m", argv[i]);
+
+                        p = pbuf;
+                }
+
+                r = image_policy_to_string(p, /* simplify= */ false, &as_string);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to format policy '%s' as string: %m", argv[i]);
+
+                r = image_policy_to_string(p, /* simplify= */ true, &as_string_simplified);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to format policy '%s' as string: %m", argv[i]);
+
+                pager_open(arg_pager_flags);
+
+                if (streq(as_string, as_string_simplified))
+                        printf("Analyzing policy: %s%s%s\n", ansi_highlight_magenta_underline(), as_string, ansi_normal());
+                else
+                        printf("Analyzing policy: %s%s%s\n"
+                               "       Long form: %s%s%s\n",
+                               ansi_highlight(), as_string_simplified, ansi_normal(),
+                               ansi_grey(), as_string, ansi_normal());
+
+                table = table_new("partition", "mode", "read-only", "growfs");
+                if (!table)
+                        return log_oom();
+
+                (void) table_set_ersatz_string(table, TABLE_ERSATZ_DASH);
+
+                for (PartitionDesignator d = 0; d < _PARTITION_DESIGNATOR_MAX; d++) {
+                        PartitionPolicyFlags f = image_policy_get_exhaustively(p, d);
+                        assert(f >= 0);
+
+                        r = table_add_designator_line(table, d, f);
+                        if (r < 0)
+                                return r;
+                }
+
+                r = table_add_designator_line(table, _PARTITION_DESIGNATOR_INVALID, image_policy_default(p));
+                if (r < 0)
+                        return r;
+
+                putc('\n', stdout);
+
+                r = table_print(table, NULL);
+                if (r < 0)
+                        return r;
+        }
+
+        return EXIT_SUCCESS;
+}
diff --git a/src/analyze/analyze-image-policy.h b/src/analyze/analyze-image-policy.h
new file mode 100644
index 0000000000..fa08447822
--- /dev/null
+++ b/src/analyze/analyze-image-policy.h
@@ -0,0 +1,3 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+int verb_image_policy(int argc, char *argv[], void *userdata);
diff --git a/src/analyze/analyze.c b/src/analyze/analyze.c
index 0246da4b45..ddc71b98b0 100644
--- a/src/analyze/analyze.c
+++ b/src/analyze/analyze.c
@@ -39,6 +39,7 @@
 #include "analyze-unit-files.h"
 #include "analyze-unit-paths.h"
 #include "analyze-verify.h"
+#include "analyze-image-policy.h"
 #include "build.h"
 #include "bus-error.h"
 #include "bus-locator.h"
@@ -109,6 +110,7 @@ bool arg_quiet = false;
 char *arg_profile = NULL;
 bool arg_legend = true;
 bool arg_table = false;
+ImagePolicy *arg_image_policy = NULL;
 
 STATIC_DESTRUCTOR_REGISTER(arg_dot_from_patterns, strv_freep);
 STATIC_DESTRUCTOR_REGISTER(arg_dot_to_patterns, strv_freep);
@@ -117,6 +119,7 @@ STATIC_DESTRUCTOR_REGISTER(arg_image, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_security_policy, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_unit, freep);
 STATIC_DESTRUCTOR_REGISTER(arg_profile, freep);
+STATIC_DESTRUCTOR_REGISTER(arg_image_policy, image_policy_freep);
 
 int acquire_bus(sd_bus **bus, bool *use_full_bus) {
         int r;
@@ -268,6 +271,7 @@ static int help(int argc, char *argv[], void *userdata) {
                "  -q --quiet                 Do not emit hints\n"
                "     --root=PATH             Operate on an alternate filesystem root\n"
                "     --image=PATH            Operate on disk image as filesystem root\n"
+               "     --image-policy=POLICY   Specify disk image dissection policy\n"
                "\nSee the %s for details.\n",
                program_invocation_short_name,
                ansi_highlight(),
@@ -307,6 +311,7 @@ static int parse_argv(int argc, char *argv[]) {
                 ARG_PROFILE,
                 ARG_TABLE,
                 ARG_NO_LEGEND,
+                ARG_IMAGE_POLICY,
         };
 
         static const struct option options[] = {
@@ -339,6 +344,7 @@ static int parse_argv(int argc, char *argv[]) {
                 { "profile",          required_argument, NULL, ARG_PROFILE          },
                 { "table",            optional_argument, NULL, ARG_TABLE            },
                 { "no-legend",        optional_argument, NULL, ARG_NO_LEGEND        },
+                { "image-policy",     required_argument, NULL, ARG_IMAGE_POLICY     },
                 {}
         };
 
@@ -522,6 +528,18 @@ static int parse_argv(int argc, char *argv[]) {
                         arg_legend = false;
                         break;
 
+                case ARG_IMAGE_POLICY: {
+                        _cleanup_(image_policy_freep) ImagePolicy *p = NULL;
+
+                        r = image_policy_from_string(optarg, &p);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to parse image policy: %s", optarg);
+
+                        image_policy_free(arg_image_policy);
+                        arg_image_policy = TAKE_PTR(p);
+                        break;
+                }
+
                 case '?':
                         return -EINVAL;
 
@@ -623,6 +641,7 @@ static int run(int argc, char *argv[]) {
                 { "inspect-elf",       2,        VERB_ANY, 0,            verb_elf_inspection    },
                 { "malloc",            VERB_ANY, VERB_ANY, 0,            verb_malloc            },
                 { "fdstore",           2,        VERB_ANY, 0,            verb_fdstore           },
+                { "image-policy",      2,        2,        0,            verb_image_policy      },
                 {}
         };
 
@@ -643,6 +662,7 @@ static int run(int argc, char *argv[]) {
 
                 r = mount_image_privately_interactively(
                                 arg_image,
+                                arg_image_policy,
                                 DISSECT_IMAGE_GENERIC_ROOT |
                                 DISSECT_IMAGE_RELAX_VAR_CHECK |
                                 DISSECT_IMAGE_READ_ONLY,
diff --git a/src/analyze/analyze.h b/src/analyze/analyze.h
index 2f623e3201..84575cd9a9 100644
--- a/src/analyze/analyze.h
+++ b/src/analyze/analyze.h
@@ -38,6 +38,7 @@ extern bool arg_quiet;
 extern char *arg_profile;
 extern bool arg_legend;
 extern bool arg_table;
+extern ImagePolicy *arg_image_policy;
 
 int acquire_bus(sd_bus **bus, bool *use_full_bus);
 
diff --git a/src/analyze/meson.build b/src/analyze/meson.build
index 695089a0be..c50c35f09f 100644
--- a/src/analyze/meson.build
+++ b/src/analyze/meson.build
@@ -13,6 +13,7 @@ systemd_analyze_sources = files(
         'analyze-exit-status.c',
         'analyze-fdstore.c',
         'analyze-filesystems.c',
+        'analyze-image-policy.c',
         'analyze-inspect-elf.c',
         'analyze-log-control.c',
         'analyze-malloc.c',