diff options
Diffstat (limited to 'src/collectors/systemd-journal.plugin/systemd-journal-dyncfg.c')
| -rw-r--r-- | src/collectors/systemd-journal.plugin/systemd-journal-dyncfg.c | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/src/collectors/systemd-journal.plugin/systemd-journal-dyncfg.c b/src/collectors/systemd-journal.plugin/systemd-journal-dyncfg.c new file mode 100644 index 000000000..469f9d2cf --- /dev/null +++ b/src/collectors/systemd-journal.plugin/systemd-journal-dyncfg.c @@ -0,0 +1,163 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#include "systemd-internals.h" + +#define JOURNAL_DIRECTORIES_JSON_NODE "journalDirectories" + +static bool is_directory(const char *dir) { + struct stat statbuf; + if (stat(dir, &statbuf) != 0) { + // Error in stat() means the path probably doesn't exist or can't be accessed. + return false; + } + // S_ISDIR macro is true if the path is a directory. + return S_ISDIR(statbuf.st_mode) ? true : false; +} + +static const char *is_valid_dir(const char *dir) { + if(strcmp(dir, "/") == 0) + return "/ is not acceptable"; + + if(!strstartswith(dir, "/")) + return "only directories starting with / are accepted"; + + if(strstr(dir, "/./")) + return "directory contains /./"; + + if(strstr(dir, "/../") || strendswith(dir, "/..")) + return "directory contains /../"; + + if(strstartswith(dir, "/dev/") || strcmp(dir, "/dev") == 0) + return "directory contains /dev"; + + if(strstartswith(dir, "/proc/") || strcmp(dir, "/proc") == 0) + return "directory contains /proc"; + + if(strstartswith(dir, "/sys/") || strcmp(dir, "/sys") == 0) + return "directory contains /sys"; + + if(strstartswith(dir, "/etc/") || strcmp(dir, "/etc") == 0) + return "directory contains /etc"; + + if(strstartswith(dir, "/lib/") || strcmp(dir, "/lib") == 0 + || strstartswith(dir, "/lib32/") || strcmp(dir, "/lib32") == 0 + || strstartswith(dir, "/lib64/") || strcmp(dir, "/lib64") == 0) + return "directory contains /lib"; + + return NULL; +} + +static int systemd_journal_directories_dyncfg_update(BUFFER *result, BUFFER *payload) { + if(!payload || !buffer_strlen(payload)) + return dyncfg_default_response(result, HTTP_RESP_BAD_REQUEST, "empty payload received"); + + CLEAN_JSON_OBJECT *jobj = json_tokener_parse(buffer_tostring(payload)); + if(!jobj) + return dyncfg_default_response(result, HTTP_RESP_BAD_REQUEST, "cannot parse json payload"); + + struct json_object *journalDirectories; + json_object_object_get_ex(jobj, JOURNAL_DIRECTORIES_JSON_NODE, &journalDirectories); + + size_t n_directories = json_object_array_length(journalDirectories); + if(n_directories > MAX_JOURNAL_DIRECTORIES) + return dyncfg_default_response(result, HTTP_RESP_BAD_REQUEST, "too many directories configured"); + + // validate the directories + for(size_t i = 0; i < n_directories; i++) { + struct json_object *dir = json_object_array_get_idx(journalDirectories, i); + const char *s = json_object_get_string(dir); + if(s && *s) { + const char *msg = is_valid_dir(s); + if(msg) + return dyncfg_default_response(result, HTTP_RESP_BAD_REQUEST, msg); + } + } + + size_t added = 0, not_found = 0; + for(size_t i = 0; i < n_directories; i++) { + struct json_object *dir = json_object_array_get_idx(journalDirectories, i); + const char *s = json_object_get_string(dir); + if(s && *s) { + string_freez(journal_directories[added].path); + journal_directories[added++].path = string_strdupz(s); + + if(!is_directory(s)) + not_found++; + } + } + + if(!added) + return dyncfg_default_response(result, HTTP_RESP_BAD_REQUEST, "no directories in the payload"); + else { + for(size_t i = added; i < MAX_JOURNAL_DIRECTORIES; i++) { + string_freez(journal_directories[i].path); + journal_directories[i].path = NULL; + } + } + + journal_watcher_restart(); + + return dyncfg_default_response(result, HTTP_RESP_OK, not_found ? "added, but some directories are not found in the filesystem" : ""); +} + +static int systemd_journal_directories_dyncfg_get(BUFFER *wb) { + buffer_flush(wb); + buffer_json_initialize(wb, "\"", "\"", 0, true, BUFFER_JSON_OPTIONS_MINIFY); + + buffer_json_member_add_array(wb, JOURNAL_DIRECTORIES_JSON_NODE); + for(size_t i = 0; i < MAX_JOURNAL_DIRECTORIES ;i++) { + if(!journal_directories[i].path) + break; + + buffer_json_add_array_item_string(wb, string2str(journal_directories[i].path)); + } + buffer_json_array_close(wb); + + buffer_json_finalize(wb); + return HTTP_RESP_OK; +} + +static int systemd_journal_directories_dyncfg_cb(const char *transaction, + const char *id, + DYNCFG_CMDS cmd, + const char *add_name __maybe_unused, + BUFFER *payload, + usec_t *stop_monotonic_ut __maybe_unused, + bool *cancelled __maybe_unused, + BUFFER *result, + HTTP_ACCESS access __maybe_unused, + const char *source __maybe_unused, + void *data __maybe_unused) { + CLEAN_BUFFER *action = buffer_create(100, NULL); + dyncfg_cmds2buffer(cmd, action); + + if(cmd == DYNCFG_CMD_GET) + return systemd_journal_directories_dyncfg_get(result); + + if(cmd == DYNCFG_CMD_UPDATE) + return systemd_journal_directories_dyncfg_update(result, payload); + + nd_log(NDLS_COLLECTORS, NDLP_ERR, + "DYNCFG: unhandled transaction '%s', id '%s' cmd '%s', payload: %s", + transaction, id, buffer_tostring(action), payload ? buffer_tostring(payload) : ""); + + return dyncfg_default_response(result, HTTP_RESP_BAD_REQUEST, "the command is not handled by this plugin"); +} + +// ---------------------------------------------------------------------------- + +void systemd_journal_dyncfg_init(struct functions_evloop_globals *wg) { + functions_evloop_dyncfg_add( + wg, + "systemd-journal:monitored-directories", + "/logs/systemd-journal", + DYNCFG_STATUS_RUNNING, + DYNCFG_TYPE_SINGLE, + DYNCFG_SOURCE_TYPE_INTERNAL, + "internal", + DYNCFG_CMD_SCHEMA | DYNCFG_CMD_GET | DYNCFG_CMD_UPDATE, + HTTP_ACCESS_NONE, + HTTP_ACCESS_NONE, + systemd_journal_directories_dyncfg_cb, + NULL); +} |