1 files changed, 142 insertions, 0 deletions
diff --git a/src/shared/journal-util.c b/src/shared/journal-util.c
new file mode 100644
index 0000000..ea396fc
--- /dev/null
+++ b/src/shared/journal-util.c
@@ -0,0 +1,142 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "acl-util.h"
+#include "fs-util.h"
+#include "hashmap.h"
+#include "journal-internal.h"
+#include "journal-util.h"
+#include "log.h"
+#include "strv.h"
+#include "user-util.h"
+
+static int access_check_var_log_journal(sd_journal *j, bool want_other_users) {
+        int r;
+
+        assert(j);
+
+        /* If we are root, we should have access, don't warn. */
+        if (getuid() == 0)
+                return 0;
+
+        /* If we are in the 'systemd-journal' group, we should have
+         * access too. */
+        r = in_group("systemd-journal");
+        if (r < 0)
+                return log_error_errno(r, "Failed to check if we are in the 'systemd-journal' group: %m");
+        if (r > 0)
+                return 0;
+
+#if HAVE_ACL
+        _cleanup_strv_free_ char **g = NULL;
+        const char* dir;
+
+        if (laccess("/run/log/journal", F_OK) >= 0)
+                dir = "/run/log/journal";
+        else
+                dir = "/var/log/journal";
+
+        /* If we are in any of the groups listed in the journal ACLs,
+         * then all is good, too. Let's enumerate all groups from the
+         * default ACL of the directory, which generally should allow
+         * access to most journal files too. */
+        r = acl_search_groups(dir, &g);
+        if (r < 0)
+                return log_error_errno(r, "Failed to search journal ACL: %m");
+        if (r > 0)
+                return 0;
+
+        /* Print a pretty list, if there were ACLs set. */
+        if (!strv_isempty(g)) {
+                _cleanup_free_ char *s = NULL;
+
+                /* There are groups in the ACL, let's list them */
+                r = strv_extend(&g, "systemd-journal");
+                if (r < 0)
+                        return log_oom();
+
+                strv_sort(g);
+                strv_uniq(g);
+
+                s = strv_join(g, "', '");
+                if (!s)
+                        return log_oom();
+
+                log_notice("Hint: You are currently not seeing messages from %s.\n"
+                           "      Users in groups '%s' can see all messages.\n"
+                           "      Pass -q to turn off this notice.",
+                           want_other_users ? "other users and the system" : "the system",
+                           s);
+                return 1;
+        }
+#endif
+
+        /* If no ACLs were found, print a short version of the message. */
+        log_notice("Hint: You are currently not seeing messages from %s.\n"
+                   "      Users in the 'systemd-journal' group can see all messages. Pass -q to\n"
+                   "      turn off this notice.",
+                   want_other_users ? "other users and the system" : "the system");
+
+        return 1;
+}
+
+int journal_access_blocked(sd_journal *j) {
+        return hashmap_contains(j->errors, INT_TO_PTR(-EACCES));
+}
+
+int journal_access_check_and_warn(sd_journal *j, bool quiet, bool want_other_users) {
+        void *code;
+        char *path;
+        int r = 0;
+
+        assert(j);
+
+        if (hashmap_isempty(j->errors)) {
+                if (ordered_hashmap_isempty(j->files) && !quiet)
+                        log_notice("No journal files were found.");
+
+                return 0;
+        }
+
+        if (journal_access_blocked(j)) {
+                if (!quiet)
+                        (void) access_check_var_log_journal(j, want_other_users);
+
+                if (ordered_hashmap_isempty(j->files))
+                        r = log_error_errno(EACCES, "No journal files were opened due to insufficient permissions.");
+        }
+
+        HASHMAP_FOREACH_KEY(path, code, j->errors) {
+                int err;
+
+                err = abs(PTR_TO_INT(code));
+
+                switch (err) {
+                case EACCES:
+                        continue;
+
+                case ENODATA:
+                        log_warning_errno(err, "Journal file %s is truncated, ignoring file.", path);
+                        break;
+
+                case EPROTONOSUPPORT:
+                        log_warning_errno(err, "Journal file %1$s uses an unsupported feature, ignoring file.\n"
+                                               "Use SYSTEMD_LOG_LEVEL=debug journalctl --file=%1$s to see the details.",
+                                               path);
+                        break;
+
+                case EBADMSG:
+                        log_warning_errno(err, "Journal file %s corrupted, ignoring file.", path);
+                        break;
+
+                case ETOOMANYREFS:
+                        log_warning_errno(err, "Too many journal files (limit is at %u) in scope, ignoring file '%s'.", JOURNAL_FILES_MAX, path);
+                        break;
+
+                default:
+                        log_warning_errno(err, "An error was encountered while opening journal file or directory %s, ignoring file: %m", path);
+                        break;
+                }
+        }
+
+        return r;
+}