当我跑步时
$ /usr/sbin/iptables -I INPUT -p tcp --dport 80 -j ACCEPT
从命令行它工作正常。但是当我编译并运行这段代码时
#include <unistd.h>
int main() {
char *args[6];
args[0] = "/usr/sbin/iptables";
args[1] = "-I INPUT";
args[2] = "-p tcp";
args[3] = "--dport 80";
args[4] = "-j ACCEPT";
args[5] = NULL;
execve(args[0], args, NULL);
}
我得到以下输出
$ ./code
iptables v1.4.6: unknown protocol ` tcp' specified
Try `iptables -h' or 'iptables --help' for more information.
我尝试删除空格
#include <unistd.h>
int main() {
char *args[6];
args[0] = "/usr/sbin/iptables";
args[1] = "-I INPUT";
args[2] = "-ptcp";
args[3] = "--dport 80";
args[4] = "-j ACCEPT";
args[5] = NULL;
execve(args[0], args, NULL);
}
我得到了
$./code
iptables v1.4.6: unknown option `--dport 80'
Try `iptables -h' or 'iptables --help' for more information.
有人可以帮我从这里出去吗?我究竟做错了什么?
这是帮助输出
$ iptables --help
iptables v1.4.6
Usage: iptables -[AD] chain rule-specification [options]
iptables -I chain [rulenum] rule-specification [options]
iptables -R chain rulenum rule-specification [options]
iptables -D chain rulenum [options]
iptables -[LS] [chain [rulenum]] [options]
iptables -[FZ] [chain] [options]
iptables -[NX] chain
iptables -E old-chain-name new-chain-name
iptables -P chain target [options]
iptables -h (print this help information)
Commands:
Either long or short options are allowed.
--append -A chain Append to chain
--delete -D chain Delete matching rule from chain
--delete -D chain rulenum
Delete rule rulenum (1 = first) from chain
--insert -I chain [rulenum]
Insert in chain as rulenum (default 1=first)
--replace -R chain rulenum
Replace rule rulenum (1 = first) in chain
--list -L [chain [rulenum]]
List the rules in a chain or all chains
--list-rules -S [chain [rulenum]]
Print the rules in a chain or all chains
--flush -F [chain] Delete all rules in chain or all chains
--zero -Z [chain [rulenum]]
Zero counters in chain or all chains
--new -N chain Create a new user-defined chain
--delete-chain
-X [chain] Delete a user-defined chain
--policy -P chain target
Change policy on chain to target
--rename-chain
-E old-chain new-chain
Change chain name, (moving any references)
Options:
[!] --proto -p proto protocol: by number or name, eg. `tcp'
[!] --source -s address[/mask][...]
source specification
[!] --destination -d address[/mask][...]
destination specification
[!] --in-interface -i input name[+]
network interface name ([+] for wildcard)
--jump -j target
target for rule (may load target extension)
--goto -g chain
jump to chain with no return
--match -m match
extended match (may load extension)
--numeric -n numeric output of addresses and ports
[!] --out-interface -o output name[+]
network interface name ([+] for wildcard)
--table -t table table to manipulate (default: `filter')
--verbose -v verbose mode
--line-numbers print line numbers when listing
--exact -x expand numbers (display exact values)
[!] --fragment -f match second or further fragments only
--modprobe=<command> try to insert modules using this command
--set-counters PKTS BYTES set the counter during insert/append
[!] --version -V print package version.
答案1
您需要以与 shell 相同的方式拆分参数:
#include <unistd.h>
int main() {
char *args[10];
int i = 0;
args[i++] = "/usr/sbin/iptables";
args[i++] = "-I";
args[i++] = "INPUT";
args[i++] = "-p";
args[i++] = "tcp";
args[i++] = "--dport";
args[i++] = "80";
args[i++] = "-j";
args[i++] = "ACCEPT";
args[i++] = NULL;
execve(args[0], args, NULL);
}
外壳裂开全部空间。
答案2
标志和它们的参数应该是分开的:
int main() {
char *args[] = {
"/usr/sbin/iptables",
"-I", "INPUT",
"-ptcp",
"--dport", "80",
"-j", "ACCEPT",
NULL
};
...
}
对于选项和选项参数可以作为单个参数给出的命令,它们之间不应有空格(例如,tail
和),或者根据命令-n6
使用分隔符,例如和。=
grep
--color=always