* foolproof the hex-decoder

[citadel.git] / libcitadel / lib / mime_parser.c

diff --git a/libcitadel/lib/mime_parser.c b/libcitadel/lib/mime_parser.c
index 66f8c0c782d70f4e14871303b9060565f501f8ca..85f955c0c5e10b57b3a88b6dda8ace7d7e9644b4 100644 (file)
--- a/libcitadel/lib/mime_parser.c
+++ b/libcitadel/lib/mime_parser.c
@@ -71,35 +71,41 @@ char *fixed_partnum(char *supplied_partnum) {
 }
 
 
-unsigned int decode_hex(char *Source)
+static inline unsigned int _decode_hex(char *Source)
 {
        int ret = 0;
-       if (*Source  < 'A') {
+       if      ((*Source >= '0') && (*Source <= '9')) {
                ret += (*Source - '0');
        }
-       else if (*Source > 'Z') {
+       else if ((*Source >= 'A') && (*Source <= 'F')) {
+               ret += (*Source - 'A' + 10);
+       }
+       else if ((*Source >= 'a') && (*Source <= 'f')) {
                ret += (*Source - 'a' + 10);
        }
        else {
-               ret += (*Source - 'A' + 10);
+               return '?';
        }
-
+               
        ret = ret << 4;
-
-       if (*(Source + 1) < 'A') {
-               ret += (*(Source + 1) - '0');
+       
+       if      ((*(Source + 1) >= '0') && (*(Source + 1) <= '9')) {
+               ret |= (*(Source + 1) - '0');
        }
-       else if (*(Source + 1) > 'Z') {
-               ret += (*(Source + 1) - 'a' + 10);
+       else if ((*(Source + 1) >= 'A') && (*(Source + 1) <= 'F')) {
+               ret |= (*(Source + 1) - 'A' + 10);
        }
-       else {
-               ret += (*(Source + 1) - 'A' + 10);
+       else if ((*(Source + 1) >= 'a') && (*(Source + 1) <= 'f')) {
+               ret |= (*(Source + 1) - 'a' + 10);
        }
-       if (ret > 255)
+       else {
                return '?';
+       }
        return ret;
 }
 
+unsigned int decode_hex(char *Source) {return _decode_hex(Source);}
+
 /*
  * Convert "quoted-printable" to binary.  Returns number of bytes decoded.
  * according to RFC2045 section 6.7
@@ -122,7 +128,7 @@ int CtdlDecodeQuotedPrintable(char *decoded, char *encoded, int sourcelen) {
                else if (encoded[pos] == '=')
                {
                        ch = 0;
-                       ch = decode_hex(&encoded[pos+1]);
+                       ch = _decode_hex(&encoded[pos+1]);
                        pos += 3;
                        decoded[decoded_length++] = ch;
                }