holm/endlessh
1
1
Fork 0
forked from extern/endlessh
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Add -l to control banner line length

Browse Source
This commit is contained in:
Christopher Wellons 2019-02-03 09:34:41 -05:00
parent ce7e3e5914
commit 66c549c87c
2 changed files with 21 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
README.md
View File

@ -16,9 +16,10 @@ trap multiple clients at a time.
Usage information is printed with `-h`.
```
Usage: endlessh [-vh] [-d MSECS] [-m LIMIT] [-p PORT]
Usage: endlessh [-vh] [-d MSECS] [-l LEN] [-m LIMIT] [-p PORT]
-d INT Message millisecond delay [10000]
-h Print this help message and exit
-l INT Maximum banner line length (3-255) [32]
-m INT Maximum number of clients [4096]
-p INT Listening port [2222]
-v Print diagnostics to standard output (repeatable)

24
endlessh.c
View File

@ -17,6 +17,7 @@
#include <netinet/in.h>
#define DEFAULT_MAX_CLIENTS 4096
#define DEFAULT_LINE_LENGTH 32
#define DEFAULT_PORT 2222
#define DEFAULT_DELAY 10000 // milliseconds
@ -220,9 +221,9 @@ check(int r)
}
static int
randline(char *line)
randline(char *line, int maxlen)
{
int len = 3 + rand() % 61;
int len = 3 + rand() % (maxlen - 2);
for (int i = 0; i < len - 2; i++)
line[i] = 32 + rand() % 95;
line[len - 2] = 13;
@ -244,10 +245,13 @@ sigterm_handler(int signal)
static void
usage(FILE *f)
{
fprintf(f, "Usage: endlessh [-vh] [-d MSECS] [-m LIMIT] [-p PORT]\n");
fprintf(f, "Usage: endlessh [-vh] [-d MSECS] [-l LEN] "
"[-m LIMIT] [-p PORT]\n");
fprintf(f, " -d INT Message millisecond delay ["
XSTR(DEFAULT_DELAY) "]\n");
fprintf(f, " -h Print this help message and exit\n");
fprintf(f, " -l INT Maximum banner line length (3-255) ["
XSTR(DEFAULT_LINE_LENGTH) "]\n");
fprintf(f, " -m INT Maximum number of clients ["
XSTR(DEFAULT_MAX_CLIENTS) "]\n");
fprintf(f, " -p INT Listening port [" XSTR(DEFAULT_PORT) "]\n");
@ -259,11 +263,12 @@ int
main(int argc, char **argv)
{
int port = DEFAULT_PORT;
int max_length = DEFAULT_LINE_LENGTH;
long delay = DEFAULT_DELAY;
long max_clients = DEFAULT_MAX_CLIENTS;
int option;
while ((option = getopt(argc, argv, "d:hm:p:v")) != -1) {
while ((option = getopt(argc, argv, "d:hl:m:p:v")) != -1) {
long tmp;
char *end;
switch (option) {
@ -278,6 +283,15 @@ main(int argc, char **argv)
usage(stdout);
exit(EXIT_SUCCESS);
break;
case 'l':
tmp = strtol(optarg, &end, 10);
if (errno || *end || tmp < 3 || tmp > 255) {
fprintf(stderr, "endlessh: Invalid line length: %s\n",
optarg);
exit(EXIT_FAILURE);
}
max_length = tmp;
break;
case 'm':
tmp = strtol(optarg, &end, 10);
if (errno || *end || tmp < 0) {
@ -411,7 +425,7 @@ main(int argc, char **argv)
} else if (revents & POLLOUT) {
char line[256];
int len = randline(line);
int len = randline(line, max_length);
/* Don't really care if send is short */
ssize_t out = send(fd, line, len, MSG_DONTWAIT);
if (out < 0)