diff options
Diffstat (limited to 'extensions/libipt_string.c')
| -rw-r--r-- | extensions/libipt_string.c | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/extensions/libipt_string.c b/extensions/libipt_string.c index dbed67db..99611a3f 100644 --- a/extensions/libipt_string.c +++ b/extensions/libipt_string.c @@ -24,7 +24,8 @@ help(void) { printf( "STRING match v%s options:\n" -"--string [!] string Match a string in a packet\n", +"--string [!] string Match a string in a packet\n" +"--hex-string [!] string Match a hex string in a packet\n", IPTABLES_VERSION); fputc('\n', stdout); @@ -32,6 +33,7 @@ IPTABLES_VERSION); static struct option opts[] = { { "string", 1, 0, '1' }, + { "hex-string", 1, 0, '2' }, {0} }; @@ -45,6 +47,13 @@ init(struct ipt_entry_match *m, unsigned int *nfcache) static void parse_string(const unsigned char *s, struct ipt_string_info *info) { + if (strlen(s) <= BM_MAX_NLEN) strcpy(info->string, s); + else exit_error(PARAMETER_PROBLEM, "STRING too long `%s'", s); +} + +static void +parse_hex_string(const unsigned char *s, struct ipt_string_info *info) +{ int i=0, slen, sindex=0, schar; short hex_f = 0, literal_f = 0; char hextmp[3]; @@ -90,6 +99,10 @@ parse_string(const unsigned char *s, struct ipt_string_info *info) /* must end with a "|" */ exit_error(PARAMETER_PROBLEM, "Invalid hex block"); } + if (! isxdigit(s[i])) /* check for valid hex char */ + exit_error(PARAMETER_PROBLEM, "Invalid hex char `%c'", s[i]); + if (! isxdigit(s[i+1])) /* check for valid hex char */ + exit_error(PARAMETER_PROBLEM, "Invalid hex char `%c'", s[i+1]); hextmp[0] = s[i]; hextmp[1] = s[i+1]; hextmp[2] = '\0'; @@ -109,6 +122,7 @@ parse_string(const unsigned char *s, struct ipt_string_info *info) exit_error(PARAMETER_PROBLEM, "STRING too long `%s'", s); sindex++; } + info->len = sindex; } /* Function which parses command options; returns true if it @@ -127,7 +141,15 @@ parse(int c, char **argv, int invert, unsigned int *flags, parse_string(argv[optind-1], stringinfo); if (invert) stringinfo->invert = 1; - stringinfo->len=strlen((char *)&stringinfo->string); + stringinfo->len=strlen((char *)&stringinfo->string); + *flags = 1; + break; + + case '2': + check_inverse(optarg, &invert, &optind, 0); + parse_hex_string(argv[optind-1], stringinfo); /* sets length */ + if (invert) + stringinfo->invert = 1; *flags = 1; break; |