diff options
Diffstat (limited to 'collectors/debugfs.plugin/debugfs_plugin.c')
| -rw-r--r-- | collectors/debugfs.plugin/debugfs_plugin.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/collectors/debugfs.plugin/debugfs_plugin.c b/collectors/debugfs.plugin/debugfs_plugin.c new file mode 100644 index 000000000..9713be320 --- /dev/null +++ b/collectors/debugfs.plugin/debugfs_plugin.c @@ -0,0 +1,246 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#include "debugfs_plugin.h" +#include "libnetdata/required_dummies.h" + +static char *user_config_dir = CONFIG_DIR; +static char *stock_config_dir = LIBCONFIG_DIR; + +static int update_every = 1; + +static struct debugfs_module { + const char *name; + + int enabled; + + int (*func)(int update_every, const char *name); +} debugfs_modules[] = { + // Memory Fragmentation + { .name = "/sys/kernel/debug/extfrag", .enabled = CONFIG_BOOLEAN_YES, + .func = do_debugfs_extfrag}, + { .name = "/sys/kernel/debug/zswap", .enabled = CONFIG_BOOLEAN_YES, + .func = do_debugfs_zswap}, + + // The terminator + { .name = NULL, .enabled = CONFIG_BOOLEAN_NO, .func = NULL} +}; + +#ifdef HAVE_CAPABILITY +static int debugfs_check_capabilities() +{ + cap_t caps = cap_get_proc(); + if (!caps) { + error("Cannot get current capabilities."); + return 0; + } + + int ret = 1; + cap_flag_value_t cfv = CAP_CLEAR; + if (cap_get_flag(caps, CAP_DAC_READ_SEARCH, CAP_EFFECTIVE, &cfv) == -1) { + error("Cannot find if CAP_DAC_READ_SEARCH is effective."); + ret = 0; + } else { + if (cfv != CAP_SET) { + error("debugfs.plugin should run with CAP_DAC_READ_SEARCH."); + ret = 0; + } + } + cap_free(caps); + + return ret; +} +#else +static int debugfs_check_capabilities() +{ + return 0; +} +#endif + +// TODO: This is a function used by 3 different collector, we should do it global (next PR) +static int debugfs_am_i_running_as_root() +{ + uid_t uid = getuid(), euid = geteuid(); + + if (uid == 0 || euid == 0) { + return 1; + } + + return 0; +} + +void debugfs2lower(char *name) +{ + while (*name) { + *name = tolower(*name); + name++; + } +} + +// Consiidering our goal to redce binaries, I preferred to copy function, instead to force link with unecessary libs +const char *debugfs_rrdset_type_name(RRDSET_TYPE chart_type) { + switch(chart_type) { + case RRDSET_TYPE_LINE: + default: + return RRDSET_TYPE_LINE_NAME; + + case RRDSET_TYPE_AREA: + return RRDSET_TYPE_AREA_NAME; + + case RRDSET_TYPE_STACKED: + return RRDSET_TYPE_STACKED_NAME; + } +} + +const char *debugfs_rrd_algorithm_name(RRD_ALGORITHM algorithm) { + switch(algorithm) { + case RRD_ALGORITHM_ABSOLUTE: + default: + return RRD_ALGORITHM_ABSOLUTE_NAME; + + case RRD_ALGORITHM_INCREMENTAL: + return RRD_ALGORITHM_INCREMENTAL_NAME; + + case RRD_ALGORITHM_PCENT_OVER_ROW_TOTAL: + return RRD_ALGORITHM_PCENT_OVER_ROW_TOTAL_NAME; + + case RRD_ALGORITHM_PCENT_OVER_DIFF_TOTAL: + return RRD_ALGORITHM_PCENT_OVER_DIFF_TOTAL_NAME; + } +} + +int debugfs_check_sys_permission() { + int ret = 0; + + char filename[FILENAME_MAX + 1]; + + snprintfz(filename, FILENAME_MAX, "%s/sys/kernel/debug/extfrag/extfrag_index", netdata_configured_host_prefix); + + procfile *ff = procfile_open(filename, NULL, PROCFILE_FLAG_NO_ERROR_ON_FILE_IO); + if(!ff) goto dcsp_cleanup; + + ff = procfile_readall(ff); + if(!ff) goto dcsp_cleanup; + + ret = 1; + +dcsp_cleanup: + if (!ret) + perror("Cannot open /sys/kernel/debug/extfrag/extfrag_index file"); + procfile_close(ff); + return ret; +} + +static void debugfs_parse_args(int argc, char **argv) +{ + int i, freq = 0; + for(i = 1; i < argc; i++) { + if(!freq) { + int n = (int)str2l(argv[i]); + if(n > 0) { + freq = n; + continue; + } + } + + if(strcmp("test-permissions", argv[i]) == 0 || strcmp("-t", argv[i]) == 0) { + if(!debugfs_check_sys_permission()) { + exit(2); + } + printf("OK\n"); + exit(0); + } + } + + if(freq > 0) update_every = freq; +} + +int main(int argc, char **argv) +{ + // debug_flags = D_PROCFILE; + stderror = stderr; + + // set the name for logging + program_name = "debugfs.plugin"; + + // disable syslog for debugfs.plugin + error_log_syslog = 0; + + netdata_configured_host_prefix = getenv("NETDATA_HOST_PREFIX"); + if (verify_netdata_host_prefix() == -1) + exit(1); + + user_config_dir = getenv("NETDATA_USER_CONFIG_DIR"); + if (user_config_dir == NULL) { + user_config_dir = CONFIG_DIR; + } + + stock_config_dir = getenv("NETDATA_STOCK_CONFIG_DIR"); + if (stock_config_dir == NULL) { + // info("NETDATA_CONFIG_DIR is not passed from netdata"); + stock_config_dir = LIBCONFIG_DIR; + } + + // FIXME: should first check if /sys/kernel/debug is mounted + + // FIXME: remove debugfs_check_sys_permission() after https://github.com/netdata/netdata/issues/15048 is fixed + if (!debugfs_check_capabilities() && !debugfs_am_i_running_as_root() && !debugfs_check_sys_permission()) { + uid_t uid = getuid(), euid = geteuid(); +#ifdef HAVE_CAPABILITY + error( + "debugfs.plugin should either run as root (now running with uid %u, euid %u) or have special capabilities. " + "Without these, debugfs.plugin cannot access /sys/kernel/debug. " + "To enable capabilities run: sudo setcap cap_dac_read_search,cap_sys_ptrace+ep %s; " + "To enable setuid to root run: sudo chown root:netdata %s; sudo chmod 4750 %s; ", + uid, + euid, + argv[0], + argv[0], + argv[0]); +#else + error( + "debugfs.plugin should either run as root (now running with uid %u, euid %u) or have special capabilities. " + "Without these, debugfs.plugin cannot access /sys/kernel/debug." + "Your system does not support capabilities. " + "To enable setuid to root run: sudo chown root:netdata %s; sudo chmod 4750 %s; ", + uid, + euid, + argv[0], + argv[0]); +#endif + exit(1); + } + + // if (!debugfs_check_sys_permission()) { + // exit(2); + // } + + debugfs_parse_args(argc, argv); + + size_t iteration; + usec_t step = update_every * USEC_PER_SEC; + heartbeat_t hb; + heartbeat_init(&hb); + + for (iteration = 0; iteration < 86400; iteration++) { + heartbeat_next(&hb, step); + int enabled = 0; + + for (int i = 0; debugfs_modules[i].name; i++) { + struct debugfs_module *pm = &debugfs_modules[i]; + if (unlikely(!pm->enabled)) + continue; + + pm->enabled = !pm->func(update_every, pm->name); + if (likely(pm->enabled)) + enabled++; + } + if (!enabled) { + info("all modules are disabled, exiting..."); + return 1; + } + } + + fprintf(stdout, "EXIT\n"); + fflush(stdout); + return 0; +} |