diff options
Diffstat (limited to '')
-rw-r--r-- | misc/nstat.c | 774 |
1 files changed, 774 insertions, 0 deletions
diff --git a/misc/nstat.c b/misc/nstat.c new file mode 100644 index 0000000..7160c59 --- /dev/null +++ b/misc/nstat.c @@ -0,0 +1,774 @@ +/* + * nstat.c handy utility to read counters /proc/net/netstat and snmp + * + * 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; either version + * 2 of the License, or (at your option) any later version. + * + * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> + */ + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <fcntl.h> +#include <string.h> +#include <errno.h> +#include <time.h> +#include <sys/time.h> +#include <fnmatch.h> +#include <sys/file.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <sys/poll.h> +#include <sys/wait.h> +#include <sys/stat.h> +#include <signal.h> +#include <math.h> +#include <getopt.h> + +#include <json_writer.h> +#include "version.h" +#include "utils.h" + +int dump_zeros; +int reset_history; +int ignore_history; +int no_output; +int json_output; +int no_update; +int scan_interval; +int time_constant; +double W; +char **patterns; +int npatterns; + +char info_source[128]; +int source_mismatch; + +static int generic_proc_open(const char *env, char *name) +{ + char store[128]; + char *p = getenv(env); + + if (!p) { + p = getenv("PROC_ROOT") ? : "/proc"; + snprintf(store, sizeof(store)-1, "%s/%s", p, name); + p = store; + } + return open(p, O_RDONLY); +} + +static int net_netstat_open(void) +{ + return generic_proc_open("PROC_NET_NETSTAT", "net/netstat"); +} + +static int net_snmp_open(void) +{ + return generic_proc_open("PROC_NET_SNMP", "net/snmp"); +} + +static int net_snmp6_open(void) +{ + return generic_proc_open("PROC_NET_SNMP6", "net/snmp6"); +} + +static int net_sctp_snmp_open(void) +{ + return generic_proc_open("PROC_NET_SCTP_SNMP", "net/sctp/snmp"); +} + +struct nstat_ent { + struct nstat_ent *next; + char *id; + unsigned long long val; + double rate; +}; + +struct nstat_ent *kern_db; +struct nstat_ent *hist_db; + +static const char *useless_numbers[] = { + "IpForwarding", "IpDefaultTTL", + "TcpRtoAlgorithm", "TcpRtoMin", "TcpRtoMax", + "TcpMaxConn", "TcpCurrEstab" +}; + +static int useless_number(const char *id) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(useless_numbers); i++) + if (strcmp(id, useless_numbers[i]) == 0) + return 1; + return 0; +} + +static int match(const char *id) +{ + int i; + + if (npatterns == 0) + return 1; + + for (i = 0; i < npatterns; i++) { + if (!fnmatch(patterns[i], id, FNM_CASEFOLD)) + return 1; + } + return 0; +} + +static void load_good_table(FILE *fp) +{ + char buf[4096]; + struct nstat_ent *db = NULL; + struct nstat_ent *n; + + while (fgets(buf, sizeof(buf), fp) != NULL) { + int nr; + unsigned long long val; + double rate; + char idbuf[sizeof(buf)]; + + if (buf[0] == '#') { + buf[strlen(buf)-1] = 0; + if (info_source[0] && strcmp(info_source, buf+1)) + source_mismatch = 1; + strlcpy(info_source, buf + 1, sizeof(info_source)); + continue; + } + /* idbuf is as big as buf, so this is safe */ + nr = sscanf(buf, "%s%llu%lg", idbuf, &val, &rate); + if (nr < 2) { + fprintf(stderr, "%s:%d: error parsing history file\n", + __FILE__, __LINE__); + exit(-2); + } + if (nr < 3) + rate = 0; + if (useless_number(idbuf)) + continue; + if ((n = malloc(sizeof(*n))) == NULL) { + perror("nstat: malloc"); + exit(-1); + } + n->id = strdup(idbuf); + n->val = val; + n->rate = rate; + n->next = db; + db = n; + } + + while (db) { + n = db; + db = db->next; + n->next = kern_db; + kern_db = n; + } +} + +static int count_spaces(const char *line) +{ + int count = 0; + char c; + + while ((c = *line++) != 0) + count += c == ' ' || c == '\n'; + return count; +} + +static void load_ugly_table(FILE *fp) +{ + char *buf = NULL; + size_t buflen = 0; + ssize_t nread; + struct nstat_ent *db = NULL; + struct nstat_ent *n; + + while ((nread = getline(&buf, &buflen, fp)) != -1) { + char idbuf[4096]; + int off; + char *p; + int count1, count2, skip = 0; + + p = strchr(buf, ':'); + if (!p) { + fprintf(stderr, "%s:%d: error parsing history file\n", + __FILE__, __LINE__); + exit(-2); + } + count1 = count_spaces(buf); + *p = 0; + idbuf[0] = 0; + strncat(idbuf, buf, sizeof(idbuf) - 1); + off = p - buf; + p += 2; + + while (*p) { + char *next; + + if ((next = strchr(p, ' ')) != NULL) + *next++ = 0; + else if ((next = strchr(p, '\n')) != NULL) + *next++ = 0; + if (off < sizeof(idbuf)) { + idbuf[off] = 0; + strncat(idbuf, p, sizeof(idbuf) - off - 1); + } + n = malloc(sizeof(*n)); + if (!n) { + perror("nstat: malloc"); + exit(-1); + } + n->id = strdup(idbuf); + n->rate = 0; + n->next = db; + db = n; + p = next; + } + n = db; + nread = getline(&buf, &buflen, fp); + if (nread == -1) { + fprintf(stderr, "%s:%d: error parsing history file\n", + __FILE__, __LINE__); + exit(-2); + } + count2 = count_spaces(buf); + if (count2 > count1) + skip = count2 - count1; + do { + p = strrchr(buf, ' '); + if (!p) { + fprintf(stderr, "%s:%d: error parsing history file\n", + __FILE__, __LINE__); + exit(-2); + } + *p = 0; + if (sscanf(p+1, "%llu", &n->val) != 1) { + fprintf(stderr, "%s:%d: error parsing history file\n", + __FILE__, __LINE__); + exit(-2); + } + /* Trick to skip "dummy" trailing ICMP MIB in 2.4 */ + if (skip) + skip--; + else + n = n->next; + } while (p > buf + off + 2); + } + free(buf); + + while (db) { + n = db; + db = db->next; + if (useless_number(n->id)) { + free(n->id); + free(n); + } else { + n->next = kern_db; + kern_db = n; + } + } +} + +static void load_sctp_snmp(void) +{ + FILE *fp = fdopen(net_sctp_snmp_open(), "r"); + + if (fp) { + load_good_table(fp); + fclose(fp); + } +} + +static void load_snmp(void) +{ + FILE *fp = fdopen(net_snmp_open(), "r"); + + if (fp) { + load_ugly_table(fp); + fclose(fp); + } +} + +static void load_snmp6(void) +{ + FILE *fp = fdopen(net_snmp6_open(), "r"); + + if (fp) { + load_good_table(fp); + fclose(fp); + } +} + +static void load_netstat(void) +{ + FILE *fp = fdopen(net_netstat_open(), "r"); + + if (fp) { + load_ugly_table(fp); + fclose(fp); + } +} + + +static void dump_kern_db(FILE *fp, int to_hist) +{ + json_writer_t *jw = json_output ? jsonw_new(fp) : NULL; + struct nstat_ent *n, *h; + + h = hist_db; + if (jw) { + jsonw_start_object(jw); + jsonw_pretty(jw, pretty); + jsonw_name(jw, info_source); + jsonw_start_object(jw); + } else + fprintf(fp, "#%s\n", info_source); + + for (n = kern_db; n; n = n->next) { + unsigned long long val = n->val; + + if (!dump_zeros && !val && !n->rate) + continue; + if (!match(n->id)) { + struct nstat_ent *h1; + + if (!to_hist) + continue; + for (h1 = h; h1; h1 = h1->next) { + if (strcmp(h1->id, n->id) == 0) { + val = h1->val; + h = h1->next; + break; + } + } + } + + if (jw) + jsonw_uint_field(jw, n->id, val); + else + fprintf(fp, "%-32s%-16llu%6.1f\n", n->id, val, n->rate); + } + + if (jw) { + jsonw_end_object(jw); + + jsonw_end_object(jw); + jsonw_destroy(&jw); + } +} + +static void dump_incr_db(FILE *fp) +{ + json_writer_t *jw = json_output ? jsonw_new(fp) : NULL; + struct nstat_ent *n, *h; + + h = hist_db; + if (jw) { + jsonw_start_object(jw); + jsonw_pretty(jw, pretty); + jsonw_name(jw, info_source); + jsonw_start_object(jw); + } else + fprintf(fp, "#%s\n", info_source); + + for (n = kern_db; n; n = n->next) { + int ovfl = 0; + unsigned long long val = n->val; + struct nstat_ent *h1; + + for (h1 = h; h1; h1 = h1->next) { + if (strcmp(h1->id, n->id) == 0) { + if (val < h1->val) { + ovfl = 1; + val = h1->val; + } + val -= h1->val; + h = h1->next; + break; + } + } + if (!dump_zeros && !val && !n->rate) + continue; + if (!match(n->id)) + continue; + + if (jw) + jsonw_uint_field(jw, n->id, val); + else + fprintf(fp, "%-32s%-16llu%6.1f%s\n", n->id, val, + n->rate, ovfl?" (overflow)":""); + } + + if (jw) { + jsonw_end_object(jw); + + jsonw_end_object(jw); + jsonw_destroy(&jw); + } +} + +static int children; + +static void sigchild(int signo) +{ +} + +static void update_db(int interval) +{ + struct nstat_ent *n, *h; + + n = kern_db; + kern_db = NULL; + + load_netstat(); + load_snmp6(); + load_snmp(); + load_sctp_snmp(); + + h = kern_db; + kern_db = n; + + for (n = kern_db; n; n = n->next) { + struct nstat_ent *h1; + + for (h1 = h; h1; h1 = h1->next) { + if (strcmp(h1->id, n->id) == 0) { + double sample; + unsigned long long incr = h1->val - n->val; + + n->val = h1->val; + sample = (double)incr * 1000.0 / interval; + if (interval >= scan_interval) { + n->rate += W*(sample-n->rate); + } else if (interval >= 1000) { + if (interval >= time_constant) { + n->rate = sample; + } else { + double w = W*(double)interval/scan_interval; + + n->rate += w*(sample-n->rate); + } + } + + while (h != h1) { + struct nstat_ent *tmp = h; + + h = h->next; + free(tmp->id); + free(tmp); + }; + h = h1->next; + free(h1->id); + free(h1); + break; + } + } + } +} + +#define T_DIFF(a, b) (((a).tv_sec-(b).tv_sec)*1000 + ((a).tv_usec-(b).tv_usec)/1000) + + +static void server_loop(int fd) +{ + struct timeval snaptime = { 0 }; + struct pollfd p; + + p.fd = fd; + p.events = p.revents = POLLIN; + + sprintf(info_source, "%d.%lu sampling_interval=%d time_const=%d", + getpid(), (unsigned long)random(), scan_interval/1000, time_constant/1000); + + load_netstat(); + load_snmp6(); + load_snmp(); + load_sctp_snmp(); + + for (;;) { + int status; + time_t tdiff; + struct timeval now; + + gettimeofday(&now, NULL); + tdiff = T_DIFF(now, snaptime); + if (tdiff >= scan_interval) { + update_db(tdiff); + snaptime = now; + tdiff = 0; + } + if (poll(&p, 1, scan_interval - tdiff) > 0 + && (p.revents&POLLIN)) { + int clnt = accept(fd, NULL, NULL); + + if (clnt >= 0) { + pid_t pid; + + if (children >= 5) { + close(clnt); + } else if ((pid = fork()) != 0) { + if (pid > 0) + children++; + close(clnt); + } else { + FILE *fp = fdopen(clnt, "w"); + + if (fp) + dump_kern_db(fp, 0); + exit(0); + } + } + } + while (children && waitpid(-1, &status, WNOHANG) > 0) + children--; + } +} + +static int verify_forging(int fd) +{ + struct ucred cred; + socklen_t olen = sizeof(cred); + + if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, (void *)&cred, &olen) || + olen < sizeof(cred)) + return -1; + if (cred.uid == getuid() || cred.uid == 0) + return 0; + return -1; +} + +static void usage(void) __attribute__((noreturn)); + +static void usage(void) +{ + fprintf(stderr, + "Usage: nstat [OPTION] [ PATTERN [ PATTERN ] ]\n" + " -h, --help this message\n" + " -a, --ignore ignore history\n" + " -d, --scan=SECS sample every statistics every SECS\n" + " -j, --json format output in JSON\n" + " -n, --nooutput do history only\n" + " -p, --pretty pretty print\n" + " -r, --reset reset history\n" + " -s, --noupdate don't update history\n" + " -t, --interval=SECS report average over the last SECS\n" + " -V, --version output version information\n" + " -z, --zeros show entries with zero activity\n"); + exit(-1); +} + +static const struct option longopts[] = { + { "help", 0, 0, 'h' }, + { "ignore", 0, 0, 'a' }, + { "scan", 1, 0, 'd'}, + { "nooutput", 0, 0, 'n' }, + { "json", 0, 0, 'j' }, + { "reset", 0, 0, 'r' }, + { "noupdate", 0, 0, 's' }, + { "pretty", 0, 0, 'p' }, + { "interval", 1, 0, 't' }, + { "version", 0, 0, 'V' }, + { "zeros", 0, 0, 'z' }, + { 0 } +}; + +int main(int argc, char *argv[]) +{ + char *hist_name; + struct sockaddr_un sun; + FILE *hist_fp = NULL; + int ch; + int fd; + + while ((ch = getopt_long(argc, argv, "h?vVzrnasd:t:jp", + longopts, NULL)) != EOF) { + switch (ch) { + case 'z': + dump_zeros = 1; + break; + case 'r': + reset_history = 1; + break; + case 'a': + ignore_history = 1; + break; + case 's': + no_update = 1; + break; + case 'n': + no_output = 1; + break; + case 'd': + scan_interval = 1000*atoi(optarg); + break; + case 't': + if (sscanf(optarg, "%d", &time_constant) != 1 || + time_constant <= 0) { + fprintf(stderr, "nstat: invalid time constant divisor\n"); + exit(-1); + } + break; + case 'j': + json_output = 1; + break; + case 'p': + pretty = 1; + break; + case 'v': + case 'V': + printf("nstat utility, iproute2-%s\n", version); + exit(0); + case 'h': + case '?': + default: + usage(); + } + } + + argc -= optind; + argv += optind; + + sun.sun_family = AF_UNIX; + sun.sun_path[0] = 0; + sprintf(sun.sun_path+1, "nstat%d", getuid()); + + if (scan_interval > 0) { + if (time_constant == 0) + time_constant = 60; + time_constant *= 1000; + W = 1 - 1/exp(log(10)*(double)scan_interval/time_constant); + if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { + perror("nstat: socket"); + exit(-1); + } + if (bind(fd, (struct sockaddr *)&sun, 2+1+strlen(sun.sun_path+1)) < 0) { + perror("nstat: bind"); + exit(-1); + } + if (listen(fd, 5) < 0) { + perror("nstat: listen"); + exit(-1); + } + if (daemon(0, 0)) { + perror("nstat: daemon"); + exit(-1); + } + signal(SIGPIPE, SIG_IGN); + signal(SIGCHLD, sigchild); + server_loop(fd); + exit(0); + } + + patterns = argv; + npatterns = argc; + + if ((hist_name = getenv("NSTAT_HISTORY")) == NULL) { + hist_name = malloc(128); + sprintf(hist_name, "/tmp/.nstat.u%d", getuid()); + } + + if (reset_history) + unlink(hist_name); + + if (!ignore_history || !no_update) { + struct stat stb; + + fd = open(hist_name, O_RDWR|O_CREAT|O_NOFOLLOW, 0600); + if (fd < 0) { + perror("nstat: open history file"); + exit(-1); + } + if ((hist_fp = fdopen(fd, "r+")) == NULL) { + perror("nstat: fdopen history file"); + exit(-1); + } + if (flock(fileno(hist_fp), LOCK_EX)) { + perror("nstat: flock history file"); + exit(-1); + } + if (fstat(fileno(hist_fp), &stb) != 0) { + perror("nstat: fstat history file"); + exit(-1); + } + if (stb.st_nlink != 1 || stb.st_uid != getuid()) { + fprintf(stderr, "nstat: something is so wrong with history file, that I prefer not to proceed.\n"); + exit(-1); + } + if (!ignore_history) { + FILE *tfp; + long uptime = -1; + + if ((tfp = fopen("/proc/uptime", "r")) != NULL) { + if (fscanf(tfp, "%ld", &uptime) != 1) + uptime = -1; + fclose(tfp); + } + if (uptime >= 0 && time(NULL) >= stb.st_mtime+uptime) { + fprintf(stderr, "nstat: history is aged out, resetting\n"); + if (ftruncate(fileno(hist_fp), 0) < 0) + perror("nstat: ftruncate"); + } + } + + load_good_table(hist_fp); + + hist_db = kern_db; + kern_db = NULL; + } + + if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) >= 0 && + (connect(fd, (struct sockaddr *)&sun, 2+1+strlen(sun.sun_path+1)) == 0 + || (strcpy(sun.sun_path+1, "nstat0"), + connect(fd, (struct sockaddr *)&sun, 2+1+strlen(sun.sun_path+1)) == 0)) + && verify_forging(fd) == 0) { + FILE *sfp = fdopen(fd, "r"); + + if (!sfp) { + fprintf(stderr, "nstat: fdopen failed: %s\n", + strerror(errno)); + close(fd); + } else { + load_good_table(sfp); + if (hist_db && source_mismatch) { + fprintf(stderr, "nstat: history is stale, ignoring it.\n"); + hist_db = NULL; + } + fclose(sfp); + } + } else { + if (fd >= 0) + close(fd); + if (hist_db && info_source[0] && strcmp(info_source, "kernel")) { + fprintf(stderr, "nstat: history is stale, ignoring it.\n"); + hist_db = NULL; + info_source[0] = 0; + } + load_netstat(); + load_snmp6(); + load_snmp(); + load_sctp_snmp(); + if (info_source[0] == 0) + strcpy(info_source, "kernel"); + } + + if (!no_output) { + if (ignore_history || hist_db == NULL) + dump_kern_db(stdout, 0); + else + dump_incr_db(stdout); + } + if (!no_update) { + if (ftruncate(fileno(hist_fp), 0) < 0) + perror("nstat: ftruncate"); + rewind(hist_fp); + + json_output = 0; + dump_kern_db(hist_fp, 1); + fclose(hist_fp); + } + exit(0); +} |