snow/dockapps
1
0
Fork 0
Code Issues Releases Activity

wmnet: Cope with interface name longer than 6 characters

Browse source 
After a recent change in the kernel (their commit 6e094bd) my
wireless interface name is 8 characters long, wlp3s0b1. But
the wmnet code to read the received bytes

	totalbytes_in = strtoul(&buffer[7], NULL, 10);

assumed that the interface name in /proc/net/dev would be 6 characters
long (and would start reading at position 7).

In the linux kernel mailing list I reported the regression and none
other than Al Viro replied,

> I am not sure if 'wmnet' could do this better (any suggestions?),

*snort*

well, yes - it's called scanf().  And if one is really, really nervous
about the overhead of <gasp> parsing a bunch of integers (as if fopen/
fgets/fclose alone won't cost enough to make constantly calling that
sucker a bad idea), just use ptr + <something> - 6 instead of
&buffer[<something>] in there.  That thing has just found where the
colon was (and replaced it with NUL), so dealing with "the first field
turned out to be too long and shifted everything past it" isn't hard.

******

I also took the oportunity to remove the unused variables diffpackets_{in,out}
This commit is contained in:
Carlos R. Mafra 2015-01-11 12:20:02 +00:00
parent e3c0e9452b
commit cd4947f139
2 changed files with 16 additions and 26 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

36
wmnet/drivers.c
View file

@ -59,9 +59,9 @@ static struct ifpppstatsreq ppp_stats_req;
extern char buffer[256];
extern char *in_rule_string, *out_rule_string, *device;
extern unsigned long totalbytes_in, totalbytes_out, lastbytes_in, lastbytes_out;
extern unsigned long totalpackets_in, totalpackets_out, lastpackets_in, lastpackets_out;
extern unsigned int diffpackets_in, diffpackets_out, diffbytes_in, diffbytes_out;
extern unsigned long long int totalbytes_in, totalbytes_out, lastbytes_in, lastbytes_out;
extern unsigned long long int totalpackets_in, totalpackets_out, lastpackets_in, lastpackets_out;
extern unsigned int diffbytes_in, diffbytes_out;
extern unsigned int out_rule, in_rule; /* number of rule in /proc/net/ip_acct to use */
extern Bool current_tx, current_rx, rx, tx;
@ -199,7 +199,6 @@ int updateStats_ipfwadm(void) {
totalpackets_in = strtoul(&buffer[offset], &ptr, 10);
if (totalpackets_in == lastpackets_in) break;
totalbytes_in = strtoul(ptr, NULL, 10);
diffpackets_in += totalpackets_in - lastpackets_in;
diffbytes_in += totalbytes_in - lastbytes_in;
lastpackets_in = totalpackets_in;
lastbytes_in = totalbytes_in;
@ -213,7 +212,6 @@ int updateStats_ipfwadm(void) {
totalpackets_out = strtoul(&buffer[offset], &ptr, 10);
if (totalpackets_out == lastpackets_out) break;
totalbytes_out = strtoul(ptr, NULL, 10);
diffpackets_out += totalpackets_out - lastpackets_out;
diffbytes_out += totalbytes_out - lastbytes_out;
lastpackets_out = totalpackets_out;
lastbytes_out = totalbytes_out;
@ -278,7 +276,6 @@ int updateStats_ipchains(void) {
totalpackets_in = pack;
if (totalpackets_in != lastpackets_in) {
totalbytes_in = bytes;
diffpackets_in += totalpackets_in - lastpackets_in;
diffbytes_in += totalbytes_in - lastbytes_in;
lastpackets_in = totalpackets_in;
lastbytes_in = totalbytes_in;
@ -291,7 +288,6 @@ int updateStats_ipchains(void) {
totalpackets_out = pack;
if (totalpackets_out != lastpackets_out) {
totalbytes_out = bytes;
diffpackets_out += totalpackets_out - lastpackets_out;
diffbytes_out += totalbytes_out - lastbytes_out;
lastpackets_out = totalpackets_out;
lastbytes_out = totalbytes_out;
@ -322,7 +318,7 @@ int updateStats_dev(void) {
FILE *dev;
char *ptr;
unsigned int flag = 0;
char *name;
static char interface[16];
rx = False;
tx = False;
@ -338,31 +334,27 @@ int updateStats_dev(void) {
/* IP Chain Rules for Linux kernel 2_1.x */
while(flag != (ACCOUNT_IN_FOUND|ACCOUNT_OUT_FOUND) && fgets(buffer, 256, dev)) {
ptr = buffer;
while(*ptr == ' ') ptr++;
name = ptr;
while(*ptr != ':') ptr++;
*ptr = '\0';
if (!strcmp(name, device)) {
sscanf(buffer, "%16s %llu %llu %*d %*d %*d %*d %*d %*d %llu %llu %*d %*d %*d %*d %*d %*d",
interface, &totalbytes_in, &totalpackets_in, &totalbytes_out, &totalpackets_out);
/* strip trailing colon */
ptr = interface;
while(*ptr != ':') ptr++;
*ptr = '\0';
if (!strcmp(interface, device)) {
flag = (ACCOUNT_IN_FOUND|ACCOUNT_OUT_FOUND);
totalpackets_in = strtoul(&buffer[15], NULL, 10);
if (totalpackets_in != lastpackets_in) {
totalbytes_in = strtoul(&buffer[7], NULL, 10);
diffpackets_in += totalpackets_in - lastpackets_in;
diffbytes_in += totalbytes_in - lastbytes_in;
lastpackets_in = totalpackets_in;
lastbytes_in = totalbytes_in;
rx = True;
}
totalpackets_out = strtoul(&buffer[74], NULL, 10);
if (totalpackets_out != lastpackets_out) {
totalbytes_out = strtoul(&buffer[66], NULL, 10);
diffpackets_out += totalpackets_out - lastpackets_out;
diffbytes_out += totalbytes_out - lastbytes_out;
lastpackets_out = totalpackets_out;
lastbytes_out = totalbytes_out;
@ -409,7 +401,6 @@ int updateStats_ppp(void) {
totalpackets_in = ppp_stats_req.stats.p.ppp_ipackets;
if (totalpackets_in != lastpackets_in) {
totalbytes_in = ppp_stats_req.stats.p.ppp_ibytes;
diffpackets_in += totalpackets_in - lastpackets_in;
diffbytes_in += totalbytes_in - lastbytes_in;
lastpackets_in = totalpackets_in;
lastbytes_in = totalbytes_in;
@ -420,7 +411,6 @@ int updateStats_ppp(void) {
totalpackets_out = ppp_stats_req.stats.p.ppp_opackets;
if (totalpackets_out != lastpackets_out) {
totalbytes_out =ppp_stats_req.stats.p.ppp_obytes;
diffpackets_out += totalpackets_out - lastpackets_out;
diffbytes_out += totalbytes_out - lastbytes_out;
lastpackets_out = totalpackets_out;
lastbytes_out = totalbytes_out;

6
wmnet/wmnet.h
View file

@ -75,9 +75,9 @@ typedef int (*parser_func)(void);
/* I know statically declared buffers are against GNU coding standards, so sue me */
char buffer[256], *click_command = NULL, *label = NULL;
struct timeval timenow, timelast;
unsigned long totalbytes_in, totalbytes_out, lastbytes_in, lastbytes_out;
unsigned long totalpackets_in, totalpackets_out, lastpackets_in, lastpackets_out;
unsigned int diffpackets_in, diffpackets_out, diffbytes_in, diffbytes_out;
unsigned long long int totalbytes_in, totalbytes_out, lastbytes_in, lastbytes_out;
unsigned long long int totalpackets_in, totalpackets_out, lastpackets_in, lastpackets_out;
unsigned int diffbytes_in, diffbytes_out;
unsigned int delayTime = 25000, displayDelay = 55000, maxRate = 6000;
unsigned int out_rule = 2, in_rule = 1, graphbox_height = 44; /* number of rule in /proc/net/ip_acct to use */
char *in_rule_string = NULL, *out_rule_string = NULL, *device=NULL;