-/*
- * 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 <SNAPSHOT.h>
-
-int dump_zeros = 0;
-int reset_history = 0;
-int ignore_history = 0;
-int no_output = 0;
-int no_update = 0;
-int scan_interval = 0;
-int time_constant = 0;
-double W;
-char **patterns;
-int npatterns;
-
-char info_source[128];
-int source_mismatch;
-
-int generic_proc_open(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(store, O_RDONLY);
-}
-
-int net_netstat_open(void)
-{
- return generic_proc_open("PROC_NET_NETSTAT", "net/netstat");
-}
-
-int net_snmp_open(void)
-{
- return generic_proc_open("PROC_NET_SNMP", "net/snmp");
-}
-
-int net_snmp6_open(void)
-{
- return generic_proc_open("PROC_NET_SNMP6", "net/snmp6");
-}
-
-struct nstat_ent
-{
- struct nstat_ent *next;
- char *id;
- unsigned long long val;
- unsigned long ival;
- double rate;
-};
-
-struct nstat_ent *kern_db;
-struct nstat_ent *hist_db;
-
-char *useless_numbers[] = {
-"IpForwarding", "IpDefaultTTL",
-"TcpRtoAlgorithm", "TcpRtoMin", "TcpRtoMax",
-"TcpMaxConn", "TcpCurrEstab"
-};
-
-int useless_number(char *id)
-{
- int i;
- for (i=0; i<sizeof(useless_numbers)/sizeof(*useless_numbers); i++)
- if (strcmp(id, useless_numbers[i]) == 0)
- return 1;
- return 0;
-}
-
-int match(char *id)
-{
- int i;
-
- if (npatterns == 0)
- return 1;
-
- for (i=0; i<npatterns; i++) {
- if (!fnmatch(patterns[i], id, 0))
- return 1;
- }
- return 0;
-}
-
-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;
- info_source[0] = 0;
- strncat(info_source, buf+1, sizeof(info_source)-1);
- continue;
- }
- /* idbuf is as big as buf, so this is safe */
- nr = sscanf(buf, "%s%llu%lg", idbuf, &val, &rate);
- if (nr < 2)
- abort();
- if (nr < 3)
- rate = 0;
- if (useless_number(idbuf))
- continue;
- if ((n = malloc(sizeof(*n))) == NULL)
- abort();
- n->id = strdup(idbuf);
- n->ival = (unsigned long)val;
- 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;
- }
-}
-
-
-void load_ugly_table(FILE *fp)
-{
- char buf[4096];
- struct nstat_ent *db = NULL;
- struct nstat_ent *n;
-
- while (fgets(buf, sizeof(buf), fp) != NULL) {
- char idbuf[sizeof(buf)];
- int off;
- char *p;
-
- p = strchr(buf, ':');
- if (!p)
- abort();
- *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)
- abort();
- n->id = strdup(idbuf);
- n->rate = 0;
- n->next = db;
- db = n;
- p = next;
- }
- n = db;
- if (fgets(buf, sizeof(buf), fp) == NULL)
- abort();
- do {
- p = strrchr(buf, ' ');
- if (!p)
- abort();
- *p = 0;
- if (sscanf(p+1, "%lu", &n->ival) != 1)
- abort();
- n->val = n->ival;
- /* Trick to skip "dummy" trailing ICMP MIB in 2.4 */
- if (strcmp(idbuf, "IcmpOutAddrMaskReps") == 0)
- idbuf[5] = 0;
- else
- n = n->next;
- } while (p > buf + off + 2);
- }
-
- 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;
- }
- }
-}
-
-void load_snmp(void)
-{
- FILE *fp = fdopen(net_snmp_open(), "r");
- if (fp) {
- load_ugly_table(fp);
- fclose(fp);
- }
-}
-
-void load_snmp6(void)
-{
- FILE *fp = fdopen(net_snmp6_open(), "r");
- if (fp) {
- load_good_table(fp);
- fclose(fp);
- }
-}
-
-void load_netstat(void)
-{
- FILE *fp = fdopen(net_netstat_open(), "r");
- if (fp) {
- load_ugly_table(fp);
- fclose(fp);
- }
-}
-
-void dump_kern_db(FILE *fp, int to_hist)
-{
- struct nstat_ent *n, *h;
- h = hist_db;
- 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;
- }
- }
- }
- fprintf(fp, "%-32s%-16llu%6.1f\n", n->id, val, n->rate);
- }
-}
-
-void dump_incr_db(FILE *fp)
-{
- struct nstat_ent *n, *h;
- h = hist_db;
- 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;
- fprintf(fp, "%-32s%-16llu%6.1f%s\n", n->id, val,
- n->rate, ovfl?" (overflow)":"");
- }
-}
-
-static int children;
-
-void sigchild(int signo)
-{
-}
-
-void update_db(int interval)
-{
- struct nstat_ent *n, *h;
-
- n = kern_db;
- kern_db = NULL;
-
- load_netstat();
- load_snmp6();
- load_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 incr = h1->ival - n->ival;
- n->val += incr;
- n->ival = h1->ival;
- sample = (double)(incr*1000)/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)
-
-
-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();
-
- for (;;) {
- int status;
- int 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, tdiff + scan_interval) > 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) {
- if (tdiff > 0)
- update_db(tdiff);
- dump_kern_db(fp, 0);
- }
- exit(0);
- }
- }
- }
- while (children && waitpid(-1, &status, WNOHANG) > 0)
- children--;
- }
-}
-
-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 [ -h?vVzrnasd:t: ] [ PATTERN [ PATTERN ] ]\n"
- );
- exit(-1);
-}
-
-
-int main(int argc, char *argv[])
-{
- char hist_name[128];
- struct sockaddr_un sun;
- FILE *hist_fp = NULL;
- int ch;
- int fd;
-
- while ((ch = getopt(argc, argv, "h?vVzrnasd:t:")) != 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 'v':
- case 'V':
- printf("nstat utility, iproute2-ss%s\n", SNAPSHOT);
- 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 (fork())
- exit(0);
- chdir("/");
- close(0); close(1); close(2); setsid();
- signal(SIGPIPE, SIG_IGN);
- signal(SIGCHLD, sigchild);
- server_loop(fd);
- exit(0);
- }
-
- patterns = argv;
- npatterns = argc;
-
- if (getenv("NSTAT_HISTORY"))
- snprintf(hist_name, sizeof(hist_name), getenv("NSTAT_HISTORY"));
- else
- 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;
- 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");
- ftruncate(fileno(hist_fp), 0);
- }
- }
-
- 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");
- 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();
- 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) {
- ftruncate(fileno(hist_fp), 0);
- rewind(hist_fp);
- dump_kern_db(hist_fp, 1);
- fflush(hist_fp);
- }
- exit(0);
-}