Use constants defined in arpa/nameser.h rather than magic numbers.

diff --git a/dhcp-common.c b/dhcp-common.c
index 8945d9a017a199fffccfb1c647ab1939f8cc1550..062f3e924640d79278ef7879577fc43b52460b15 100644 (file)
--- a/dhcp-common.c
+++ b/dhcp-common.c
@@ -27,6 +27,8 @@
 
 #include <sys/utsname.h>
 
+#include <arpa/nameser.h>
+
 #include <ctype.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -277,6 +279,11 @@ decode_rfc3397(char *out, size_t len, const uint8_t *p, size_t pl)
        int hops;
        uint8_t ltype;
 
+       if (pl > NS_MAXCDNAME) {
+               errno = E2BIG;
+               return -1;
+       }
+
        count = 0;
        start = out;
        start_len = len;
@@ -328,6 +335,10 @@ decode_rfc3397(char *out, size_t len, const uint8_t *p, size_t pl)
                                                errno = ENOBUFS;
                                                return -1;
                                        }
+                                       if (l + 1 > NS_MAXLABEL) {
+                                               errno = EINVAL;
+                                               return -1;
+                                       }
                                        memcpy(out, q, l);
                                        out += l;
                                        *out++ = '.';
@@ -355,6 +366,10 @@ decode_rfc3397(char *out, size_t len, const uint8_t *p, size_t pl)
        if (count)
                /* Don't count the trailing NUL */
                count--;
+       if (count > NS_MAXDNAME) {
+               errno = E2BIG;
+               return -1;
+       }
        return (ssize_t)count;
 }
 
@@ -404,7 +419,7 @@ valid_domainname(char *lbl, int type)
                    !start && *lbl != ' ' && *lbl != '\0') ||
                    isalnum(c))
                {
-                       if (++len > 63) {
+                       if (++len > NS_MAXLABEL) {
                                errno = ERANGE;
                                errset = 1;
                                break;