add fix to string match (Michael Rash)

diff --git a/extensions/libipt_string.c b/extensions/libipt_string.c
index dbed67db3a0d895f92da710020b12f65d33f262b..99611a3f9069827aa9842064bf40d11298aee412 100644 (file)
--- 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;