Fixed segfault crashes and improved code.

This commit is contained in:
Christian Deacon
2020-05-05 16:35:24 +00:00
parent ef1bb56c89
commit 66364a1f6b
3 changed files with 209 additions and 162 deletions

View File

@@ -3,10 +3,10 @@
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <getopt.h>
#include <signal.h>
#include <inttypes.h>
#include <time.h>
#include <getopt.h>
#include <net/if.h>
#include <linux/if_link.h>
@@ -45,7 +45,7 @@ void parse_command_line(int argc, char *argv[])
{
int c;
while ((c = getopt_long(argc, argv, "c:hl", opts, 0)) != -1)
while ((c = getopt_long(argc, argv, "c:lh", opts, NULL)) != -1)
{
switch (c)
{
@@ -54,10 +54,23 @@ void parse_command_line(int argc, char *argv[])
break;
case 'l':
list = 1;
break;
case 'h':
help = 1;
break;
case '?':
fprintf(stderr, "Missing argument option...\n");
break;
default:
break;
}
}
}
@@ -241,6 +254,38 @@ static int xdp_attach(int ifindex, uint32_t *xdp_flags, int prog_fd)
return EXIT_SUCCESS;
}
void SetConfigDefaultsX(struct config_map *cfg)
{
cfg->updateTime = 0;
cfg->interface = "eth0";
for (uint16_t i = 0; i < MAX_FILTERS; i++)
{
cfg->filters[i].enabled = 0;
cfg->filters[i].action = 0;
cfg->filters[i].srcIP = 0;
cfg->filters[i].dstIP = 0;
cfg->filters[i].min_id = 0;
cfg->filters[i].max_id = 4294967295;
cfg->filters[i].min_len = 0;
cfg->filters[i].max_len = 65535;
cfg->filters[i].min_ttl = 0;
cfg->filters[i].max_ttl = 255;
cfg->filters[i].tos = 0;
cfg->filters[i].tcpopts.enabled = 0;
cfg->filters[i].udpopts.enabled = 0;
cfg->filters[i].icmpopts.enabled = 0;
for (uint16_t j = 0; i < MAX_PCKT_LENGTH; i++)
{
cfg->filters[i].payloadMatch[j] = 0;
}
cfg->filters[i].payloadLen = 0;
}
}
int main(int argc, char *argv[])
{
// Parse the command line.
@@ -254,7 +299,7 @@ int main(int argc, char *argv[])
"--list -l => Print config details including filters (this will exit program after done).\n" \
"--help -h => Print help menu.\n");
exit(EXIT_SUCCESS);
return EXIT_SUCCESS;
}
// Check for --config argument.
@@ -265,85 +310,85 @@ int main(int argc, char *argv[])
}
// Initialize config.
struct config_map conf;
struct config_map *conf = malloc(sizeof(struct config_map));
SetConfigDefaults(&conf);
SetConfigDefaults(conf);
// Create last updated variable.
time_t lastUpdated = time(NULL);
// Update config.
update_config(&conf, configFile);
update_config(conf, configFile);
// Check for list option.
if (list)
{
fprintf(stdout, "Details:\n");
fprintf(stdout, "Interface Name => %s\n", conf.interface);
fprintf(stdout, "Update Time => %" PRIu16 "\n", conf.updateTime);
fprintf(stdout, "Filters Count => %" PRIu16 "\n\n", conf.filterCount);
fprintf(stdout, "Interface Name => %s\n", conf->interface);
fprintf(stdout, "Update Time => %" PRIu16 "\n", conf->updateTime);
fprintf(stdout, "Filters Count => %" PRIu16 "\n\n", conf->filterCount);
for (uint16_t i = 0; i < conf.filterCount; i++)
for (uint16_t i = 0; i < conf->filterCount; i++)
{
fprintf(stdout, "Filter #" PRIu16 ":\n");
fprintf(stdout, "Filter #%" PRIu16 ":\n", (i + 1));
// Main.
fprintf(stdout, "Enabled => %" PRIu8 "\n", conf.filters[i].enabled);
fprintf(stdout, "Action => %" PRIu8 " (0 = Block, 1 = Allow).\n", conf.filters[i].action);
fprintf(stdout, "Enabled => %" PRIu8 "\n", conf->filters[i].enabled);
fprintf(stdout, "Action => %" PRIu8 " (0 = Block, 1 = Allow).\n", conf->filters[i].action);
// IP addresses.
struct sockaddr_in sin;
sin.sin_addr.s_addr = conf.filters[i].srcIP;
sin.sin_addr.s_addr = conf->filters[i].srcIP;
fprintf(stdout, "Source IP => %s\n", inet_ntoa(sin.sin_addr));
struct sockaddr_in din;
din.sin_addr.s_addr = conf.filters[i].dstIP;
din.sin_addr.s_addr = conf->filters[i].dstIP;
fprintf(stdout, "Destination IP => %s\n", inet_ntoa(din.sin_addr));
// Other IP header information.
fprintf(stdout, "Max Length => %" PRIu16 "\n", conf.filters[i].max_len);
fprintf(stdout, "Min Length => %" PRIu16 "\n", conf.filters[i].min_len);
fprintf(stdout, "Max TTL => %" PRIu8 "\n", conf.filters[i].max_ttl);
fprintf(stdout, "Min TTL => %" PRIu8 "\n", conf.filters[i].min_ttl);
fprintf(stdout, "Max ID => %" PRIu32 "\n", conf.filters[i].max_id);
fprintf(stdout, "Min ID => %" PRIu32 "\n", conf.filters[i].min_id);
fprintf(stdout, "TOS => %" PRIu8 "\n", conf.filters[i].tos);
fprintf(stdout, "Max Length => %" PRIu16 "\n", conf->filters[i].max_len);
fprintf(stdout, "Min Length => %" PRIu16 "\n", conf->filters[i].min_len);
fprintf(stdout, "Max TTL => %" PRIu8 "\n", conf->filters[i].max_ttl);
fprintf(stdout, "Min TTL => %" PRIu8 "\n", conf->filters[i].min_ttl);
fprintf(stdout, "Max ID => %" PRIu32 "\n", conf->filters[i].max_id);
fprintf(stdout, "Min ID => %" PRIu32 "\n", conf->filters[i].min_id);
fprintf(stdout, "TOS => %" PRIu8 "\n\n", conf->filters[i].tos);
// TCP Options.
fprintf(stdout, "TCP Enabled => %" PRIu8 "\n", conf.filters[i].tcpopts.enabled);
fprintf(stdout, "TCP Source Port => %" PRIu16 "\n", conf.filters[i].tcpopts.sport);
fprintf(stdout, "TCP Destination Port => %" PRIu16 "\n", conf.filters[i].tcpopts.dport);
fprintf(stdout, "TCP URG Flag => %" PRIu8 "\n", conf.filters[i].tcpopts.urg);
fprintf(stdout, "TCP ACK Flag => %" PRIu8 "\n", conf.filters[i].tcpopts.ack);
fprintf(stdout, "TCP RST Flag => %" PRIu8 "\n", conf.filters[i].tcpopts.rst);
fprintf(stdout, "TCP PSH Flag => %" PRIu8 "\n", conf.filters[i].tcpopts.psh);
fprintf(stdout, "TCP SYN Flag => %" PRIu8 "\n", conf.filters[i].tcpopts.syn);
fprintf(stdout, "TCP FIN Flag => %" PRIu8 "\n", conf.filters[i].tcpopts.fin);
fprintf(stdout, "TCP Enabled => %" PRIu8 "\n", conf->filters[i].tcpopts.enabled);
fprintf(stdout, "TCP Source Port => %" PRIu16 "\n", conf->filters[i].tcpopts.sport);
fprintf(stdout, "TCP Destination Port => %" PRIu16 "\n", conf->filters[i].tcpopts.dport);
fprintf(stdout, "TCP URG Flag => %" PRIu8 "\n", conf->filters[i].tcpopts.urg);
fprintf(stdout, "TCP ACK Flag => %" PRIu8 "\n", conf->filters[i].tcpopts.ack);
fprintf(stdout, "TCP RST Flag => %" PRIu8 "\n", conf->filters[i].tcpopts.rst);
fprintf(stdout, "TCP PSH Flag => %" PRIu8 "\n", conf->filters[i].tcpopts.psh);
fprintf(stdout, "TCP SYN Flag => %" PRIu8 "\n", conf->filters[i].tcpopts.syn);
fprintf(stdout, "TCP FIN Flag => %" PRIu8 "\n\n", conf->filters[i].tcpopts.fin);
// UDP Options.
fprintf(stdout, "UDP Enabled => %" PRIu8 "\n", conf.filters[i].udpopts.enabled);
fprintf(stdout, "UDP Source Port => %" PRIu16 "\n", conf.filters[i].udpopts.sport);
fprintf(stdout, "UDP Destination Port => %" PRIu16 "\n", conf.filters[i].udpopts.dport);
fprintf(stdout, "UDP Enabled => %" PRIu8 "\n", conf->filters[i].udpopts.enabled);
fprintf(stdout, "UDP Source Port => %" PRIu16 "\n", conf->filters[i].udpopts.sport);
fprintf(stdout, "UDP Destination Port => %" PRIu16 "\n\n", conf->filters[i].udpopts.dport);
// ICMP Options.
fprintf(stdout, "ICMP Enabled => %" PRIu8 "\n", conf.filters[i].icmpopts.enabled);
fprintf(stdout, "ICMP Code => %" PRIu8 "\n", conf.filters[i].icmpopts.code);
fprintf(stdout, "ICMP Type => %" PRIu8 "\n", conf.filters[i].icmpopts.type);
fprintf(stdout, "ICMP Enabled => %" PRIu8 "\n", conf->filters[i].icmpopts.enabled);
fprintf(stdout, "ICMP Code => %" PRIu8 "\n", conf->filters[i].icmpopts.code);
fprintf(stdout, "ICMP Type => %" PRIu8 "\n", conf->filters[i].icmpopts.type);
fprintf(stdout, "\n");
fprintf(stdout, "\n\n");
}
exit(EXIT_SUCCESS);
return EXIT_SUCCESS;
}
// Get device.
int dev;
if ((dev = if_nametoindex(conf.interface)) < 0)
if ((dev = if_nametoindex(conf->interface)) < 0)
{
fprintf(stderr, "Error finding device %s.\n", conf.interface);
fprintf(stderr, "Error finding device %s.\n", conf->interface);
exit(EXIT_FAILURE);
return EXIT_FAILURE;
}
// XDP variables.
@@ -360,13 +405,13 @@ int main(int argc, char *argv[])
{
fprintf(stderr, "Error loading eBPF object file. File name => %s.\n", filename);
exit(EXIT_FAILURE);
return EXIT_FAILURE;
}
// Attach XDP program to device.
if (xdp_attach(dev, &xdpflags, prog_fd) != 0)
{
exit(EXIT_FAILURE);
return EXIT_FAILURE;
}
// Check for valid maps.
@@ -374,14 +419,14 @@ int main(int argc, char *argv[])
{
fprintf(stderr, "Error finding 'filters_map' BPF map\n");
exit(EXIT_FAILURE);
return EXIT_FAILURE;
}
if (count_map_fd < 0)
{
fprintf(stderr, "Error finding 'count_map' BPF map.\n");
exit(EXIT_FAILURE);
return EXIT_FAILURE;
}
// Signal.
@@ -393,13 +438,13 @@ int main(int argc, char *argv[])
time_t curTime = time(NULL);
// Check for auto-update.
if (conf.updateTime > 0 && (curTime - lastUpdated) > conf.updateTime)
if (conf->updateTime > 0 && (curTime - lastUpdated) > conf->updateTime)
{
// Update config.
update_config(&conf, configFile);
update_config(conf, configFile);
// Update BPF maps.
update_BPF(&conf);
update_BPF(conf);
// Update last updated variable.
lastUpdated = time(NULL);
@@ -411,11 +456,14 @@ int main(int argc, char *argv[])
// Detach XDP program.
if (xdp_detach(dev, xdpflags) != 0)
{
fprintf(stderr, "Error removing XDP program from device %s\n", conf.interface);
fprintf(stderr, "Error removing XDP program from device %s\n", conf->interface);
exit(EXIT_FAILURE);
return EXIT_FAILURE;
}
// Free config.
free(conf);
// Exit program successfully.
exit(EXIT_SUCCESS);
return EXIT_SUCCESS;
}