clean up

use "da" instead of "child", as it's more consistent.

Don't clamp "data_len", as it should be used when we see
"end of options" signifier, to indicate that the decode function
is eating all of the remaining data.

and, all of subsequent calls to various functions use data[1]
as the length, and ignore data_len

diff --git a/src/protocols/dhcpv4/decode.c b/src/protocols/dhcpv4/decode.c
index e7c36ee0ccc1cf8283459b0c5cfd8f5fa4753d07..f8a9ababc99e5d800273ad9f2977d75b1997b6d0 100644 (file)
--- a/src/protocols/dhcpv4/decode.c
+++ b/src/protocols/dhcpv4/decode.c
@@ -513,7 +513,7 @@ ssize_t fr_dhcpv4_decode_option(TALLOC_CTX *ctx, fr_dcursor_t *cursor,
 {
        ssize_t                 ret;
        uint8_t const           *p = data;
-       fr_dict_attr_t const    *child;
+       fr_dict_attr_t const    *da;
        fr_dict_attr_t const    *parent;
 
        FR_PROTO_TRACE("%s called to parse %zu byte(s)", __FUNCTION__, data_len);
@@ -524,20 +524,11 @@ ssize_t fr_dhcpv4_decode_option(TALLOC_CTX *ctx, fr_dcursor_t *cursor,
 
        parent = fr_dict_root(dict);
 
-       /*
-        *      DHCPv4 options don't overflow one field.  So limit the
-        *      maximum size of decoded data to the option header,
-        *      plus a maximum of 255 octets of data.
-        */
-       if (data_len > (2 + 255)) data_len = 2 +255;
-
        /*
         *      Padding / End of options
         */
-       if (p[0] == 0) return 1;                /* 0x00 - Padding option */
-       if (p[0] == 255) {                      /* 0xff - End of options signifier */
-               return data_len;
-       }
+       if (p[0] == 0) return data_len;         /* 0x00 - Padding option */
+       if (p[0] == 255) return data_len;       /* 0xff - End of options signifier */
 
        /*
         *      Everything else should be real options
@@ -547,24 +538,24 @@ ssize_t fr_dhcpv4_decode_option(TALLOC_CTX *ctx, fr_dcursor_t *cursor,
                return -1;
        }
 
-       child = fr_dict_attr_child_by_num(parent, p[0]);
-       if (!child) {
+       da = fr_dict_attr_child_by_num(parent, p[0]);
+       if (!da) {
                /*
                 *      Unknown attribute, create an octets type
                 *      attribute with the contents of the sub-option.
                 */
-               child = fr_dict_unknown_attr_afrom_num(ctx, parent, p[0]);
-               if (!child) return -1;
+               da = fr_dict_unknown_attr_afrom_num(ctx, parent, p[0]);
+               if (!da) return -1;
        }
        FR_PROTO_TRACE("decode context changed %s:%s -> %s:%s",
                       fr_table_str_by_value(fr_value_box_type_table, parent->type, "<invalid>"), parent->name,
-                      fr_table_str_by_value(fr_value_box_type_table, child->type, "<invalid>"), child->name);
+                      fr_table_str_by_value(fr_value_box_type_table, da->type, "<invalid>"), da->name);
 
-       if (child->type == FR_TYPE_VSA) return decode_vsa(ctx, cursor, child, data + 2, data[1]);
+       if (da->type == FR_TYPE_VSA) return decode_vsa(ctx, cursor, da, data + 2, data[1]);
 
-       ret = decode_value(ctx, cursor, child, data + 2, data[1]);
+       ret = decode_value(ctx, cursor, da, data + 2, data[1]);
        if (ret < 0) {
-               fr_dict_unknown_free(&child);
+               fr_dict_unknown_free(&da);
                return ret;
        }
        ret += 2; /* For header */