#include <stdio.h>
#include <string.h>
#include "internal/cryptlib.h"
+#include "internal/asn1_int.h"
#include <openssl/crypto.h>
#include <openssl/x509.h>
#include <openssl/asn1.h>
*out = stmp.data;
return stmp.length;
}
+
+/* Return 1 if host is a valid hostname and 0 otherwise */
+int asn1_valid_host(const ASN1_STRING *host)
+{
+ int hostlen = host->length;
+ const unsigned char *hostptr = host->data;
+ int type = host->type;
+ int i;
+ char width = -1;
+ unsigned short chflags = 0, prevchflags;
+
+ if (type > 0 && type < 31)
+ width = tag2nbyte[type];
+ if (width == -1 || hostlen == 0)
+ return 0;
+ /* Treat UTF8String as width 1 as any MSB set is invalid */
+ if (width == 0)
+ width = 1;
+ for (i = 0 ; i < hostlen; i+= width) {
+ prevchflags = chflags;
+ /* Value must be <= 0x7F: check upper bytes are all zeroes */
+ if (width == 4) {
+ if (*hostptr++ != 0 || *hostptr++ != 0 || *hostptr++ != 0)
+ return 0;
+ } else if (width == 2) {
+ if (*hostptr++ != 0)
+ return 0;
+ }
+ if (*hostptr > 0x7f)
+ return 0;
+ chflags = char_type[*hostptr++];
+ if (!(chflags & (CHARTYPE_HOST_ANY | CHARTYPE_HOST_WILD))) {
+ /* Nothing else allowed at start or end of string */
+ if (i == 0 || i == hostlen - 1)
+ return 0;
+ /* Otherwise invalid if not dot or hyphen */
+ if (!(chflags & (CHARTYPE_HOST_DOT | CHARTYPE_HOST_HYPHEN)))
+ return 0;
+ /*
+ * If previous is dot or hyphen then illegal unless both
+ * are hyphens: as .- -. .. are all illegal
+ */
+ if (prevchflags & (CHARTYPE_HOST_DOT | CHARTYPE_HOST_HYPHEN)
+ && ((prevchflags & CHARTYPE_HOST_DOT)
+ || (chflags & CHARTYPE_HOST_DOT)))
+ return 0;
+ }
+ }
+ return 1;
+}