decoding: removed redundant functions
Simplified the STRING BER decoding by using asn1_decode_simple_ber().
This removes complex duplicate code.
diff --git a/lib/decoding.c b/lib/decoding.c
index 1464981..baf85dd 100644
--- a/lib/decoding.c
+++ b/lib/decoding.c
@@ -55,6 +55,17 @@
static int
_asn1_get_indefinite_length_string (const unsigned char *der, int der_len, int *len);
+static int
+_asn1_decode_simple_ber (unsigned int etype, const unsigned char *der,
+ unsigned int _der_len, unsigned char **str,
+ unsigned int *str_len, unsigned int *ber_len,
+ unsigned have_tag);
+
+static int
+_asn1_decode_simple_der (unsigned int etype, const unsigned char *der,
+ unsigned int _der_len, const unsigned char **str,
+ unsigned int *str_len, unsigned have_tag);
+
static void
_asn1_error_description_tag_error (asn1_node node, char *ErrorDescription)
{
@@ -754,185 +765,6 @@
}
static int
-_asn1_extract_der_octet (asn1_node node, const unsigned char *der,
- int der_len, unsigned flags, int *bytes)
-{
- int len2, len3;
- int counter, counter_end;
- int result;
-
- len2 = asn1_get_length_der (der, der_len, &len3);
- if (len2 < -1)
- return ASN1_DER_ERROR;
-
- counter = len3 + 1;
- DECR_LEN(der_len, len3);
-
- if (len2 == -1)
- {
- if (der_len < 2)
- return ASN1_DER_ERROR;
- counter_end = der_len - 2;
- }
- else
- counter_end = der_len;
-
- if (counter_end < counter)
- return ASN1_DER_ERROR;
-
- while (counter < counter_end)
- {
- DECR_LEN(der_len, 1);
- len2 = asn1_get_length_der (der + counter, der_len, &len3);
-
- if (IS_ERR(len2, flags))
- {
- warn();
- return ASN1_DER_ERROR;
- }
-
- if (len2 >= 0)
- {
- DECR_LEN(der_len, len2+len3);
- _asn1_append_value (node, der + counter + len3, len2);
- }
- else
- { /* indefinite */
- DECR_LEN(der_len, len3);
- result =
- _asn1_extract_der_octet (node, der + counter + len3,
- der_len, flags|ASN1_DECODE_FLAG_STRICT_DER, &len2);
- if (result != ASN1_SUCCESS)
- return result;
- DECR_LEN(der_len, len2);
-
- /* check for EOC */
- if (der_len < 2 || (der[counter+len3+len2] != 0 && der[counter+len3+len2+1] != 0))
- {
- warn();
- return ASN1_DER_ERROR;
- }
- }
-
- counter += len2 + len3 + 1;
- }
-
- if (bytes)
- *bytes = counter;
-
- return ASN1_SUCCESS;
-
-cleanup:
- return result;
-}
-
-static int
-get_octet_string (asn1_node node, const unsigned char *der, int der_len,
- const unsigned char *tag, unsigned tag_len,
- int *len, unsigned flags)
-{
- int len2, len3, counter, tot_len, indefinite;
- int result;
- int orig_der_len = der_len;
-
- counter = 0;
-
- if (tag[0] & ASN1_CLASS_STRUCTURED)
- {
- tot_len = 0;
-
- indefinite = asn1_get_length_der (der, der_len, &len3);
- if (IS_ERR(indefinite, flags))
- {
- warn();
- return ASN1_DER_ERROR;
- }
-
- counter += len3;
- DECR_LEN(der_len, len3);
-
- if (indefinite >= 0)
- indefinite += len3;
-
- while (1)
- {
- if (indefinite == -1)
- {
- if (HAVE_TWO(der_len) && (der[counter] == 0) && (der[counter + 1] == 0))
- {
- counter += 2;
- DECR_LEN(der_len, 2);
- break;
- }
- }
- else if (counter >= indefinite)
- break;
-
- DECR_LEN(der_len, 1);
- if (der[counter] != ASN1_TAG_OCTET_STRING)
- {
- warn();
- return ASN1_DER_ERROR;
- }
-
- counter++;
-
- len2 = asn1_get_length_der (der + counter, der_len, &len3);
- if (len2 <= 0)
- {
- warn();
- return ASN1_DER_ERROR;
- }
-
- DECR_LEN(der_len, len3 + len2);
- counter += len3 + len2;
-
- tot_len += len2;
- }
-
- /* copy */
- if (node)
- {
- unsigned char temp[ASN1_MAX_LENGTH_SIZE];
- int ret;
-
- len2 = sizeof (temp);
-
- asn1_length_der (tot_len, temp, &len2);
- _asn1_set_value (node, temp, len2);
-
- ret = _asn1_extract_der_octet (node, der, orig_der_len, flags, NULL);
- if (ret != ASN1_SUCCESS)
- {
- warn();
- return ret;
- }
-
- }
- }
- else
- { /* NOT STRUCTURED */
- len2 = asn1_get_length_der (der, der_len, &len3);
- if (len2 < 0)
- {
- warn();
- return ASN1_DER_ERROR;
- }
-
- DECR_LEN(der_len, len3+len2);
- counter = len3 + len2;
- if (node)
- _asn1_set_value (node, der, counter);
- }
-
- *len = counter;
- return ASN1_SUCCESS;
-
-cleanup:
- return result;
-}
-
-static int
_asn1_get_indefinite_length_string (const unsigned char *der,
int der_len, int *len)
{
@@ -1040,6 +872,8 @@
int tag_len;
int indefinite, result, total_len = *max_ider_len, ider_len = *max_ider_len;
int inner_tag_len;
+ unsigned char *ptmp;
+ const unsigned char *ptag;
const unsigned char *der = ider;
node = *element;
@@ -1316,26 +1150,6 @@
move = RIGHT;
break;
case ASN1_ETYPE_OCTET_STRING:
- if (counter < inner_tag_len)
- {
- result = ASN1_DER_ERROR;
- warn();
- goto cleanup;
- }
-
- result = get_octet_string (p, der + counter, ider_len,
- der + counter - inner_tag_len, inner_tag_len,
- &len3, flags);
- if (result != ASN1_SUCCESS)
- {
- warn();
- goto cleanup;
- }
-
- DECR_LEN(ider_len, len3);
- counter += len3;
- move = RIGHT;
- break;
case ASN1_ETYPE_GENERALSTRING:
case ASN1_ETYPE_NUMERIC_STRING:
case ASN1_ETYPE_IA5_STRING:
@@ -1345,6 +1159,49 @@
case ASN1_ETYPE_BMP_STRING:
case ASN1_ETYPE_UTF8_STRING:
case ASN1_ETYPE_VISIBLE_STRING:
+ if (counter < inner_tag_len)
+ {
+ result = ASN1_DER_ERROR;
+ warn();
+ goto cleanup;
+ }
+
+ ptag = der + counter - inner_tag_len;
+ if (flags & ASN1_DECODE_FLAG_STRICT_DER || !(ptag[0] & ASN1_CLASS_STRUCTURED))
+
+ {
+ len2 =
+ asn1_get_length_der (der + counter, ider_len, &len3);
+ if (len2 < 0)
+ {
+ result = ASN1_DER_ERROR;
+ warn();
+ goto cleanup;
+ }
+
+ DECR_LEN(ider_len, len3+len2);
+
+ _asn1_set_value (p, der + counter, len3 + len2);
+ counter += len3 + len2;
+ }
+ else
+ {
+ result = _asn1_decode_simple_ber(type_field (p->type), der+counter, ider_len, &ptmp, (unsigned int*)&len3, (unsigned int*)&len2, 0);
+ if (result != ASN1_SUCCESS)
+ {
+ warn();
+ goto cleanup;
+ }
+
+ DECR_LEN(ider_len, len2);
+
+ _asn1_set_value (p, ptmp, len3);
+
+ counter += len2;
+ free(ptmp);
+ }
+ move = RIGHT;
+ break;
case ASN1_ETYPE_BIT_STRING:
len2 =
asn1_get_length_der (der + counter, ider_len, &len3);
@@ -2147,6 +2004,78 @@
return retCode;
}
+/*-
+ * _asn1_decode_simple_der:
+ * @etype: The type of the string to be encoded (ASN1_ETYPE_)
+ * @der: the encoded string
+ * @_der_len: the bytes of the encoded string
+ * @str: a pointer to the data
+ * @str_len: the length of the data
+ * @have_tag: whether the DER tag is included
+ *
+ * Decodes a simple DER encoded type (e.g. a string, which is not constructed).
+ * The output is a pointer inside the @der.
+ *
+ * Returns: %ASN1_SUCCESS if successful or an error value.
+ -*/
+static int
+_asn1_decode_simple_der (unsigned int etype, const unsigned char *der,
+ unsigned int _der_len, const unsigned char **str,
+ unsigned int *str_len, unsigned have_tag)
+{
+ int tag_len, len_len;
+ const unsigned char *p;
+ int der_len = _der_len;
+ unsigned char class;
+ unsigned long tag;
+ long ret;
+
+ if (der == NULL || der_len == 0)
+ return ASN1_VALUE_NOT_VALID;
+
+ if (ETYPE_OK (etype) == 0 || ETYPE_IS_STRING(etype) == 0)
+ return ASN1_VALUE_NOT_VALID;
+
+ /* doesn't handle constructed classes */
+ class = ETYPE_CLASS(etype);
+ if (class != ASN1_CLASS_UNIVERSAL)
+ return ASN1_VALUE_NOT_VALID;
+
+ p = der;
+
+ if (have_tag)
+ {
+ ret = asn1_get_tag_der (p, der_len, &class, &tag_len, &tag);
+ if (ret != ASN1_SUCCESS)
+ return ret;
+
+ if (class != ETYPE_CLASS (etype) || tag != ETYPE_TAG (etype))
+ {
+ warn();
+ return ASN1_DER_ERROR;
+ }
+
+ p += tag_len;
+ der_len -= tag_len;
+ if (der_len <= 0)
+ return ASN1_DER_ERROR;
+ }
+
+ ret = asn1_get_length_der (p, der_len, &len_len);
+ if (ret < 0)
+ return ASN1_DER_ERROR;
+
+ p += len_len;
+ der_len -= len_len;
+ if (der_len <= 0)
+ return ASN1_DER_ERROR;
+
+ *str_len = ret;
+ *str = p;
+
+ return ASN1_SUCCESS;
+}
+
/**
* asn1_decode_simple_der:
* @etype: The type of the string to be encoded (ASN1_ETYPE_)
@@ -2165,52 +2094,7 @@
unsigned int _der_len, const unsigned char **str,
unsigned int *str_len)
{
- int tag_len, len_len;
- const unsigned char *p;
- int der_len = _der_len;
- unsigned char class;
- unsigned long tag;
- long ret;
-
- if (der == NULL || der_len == 0)
- return ASN1_VALUE_NOT_VALID;
-
- if (ETYPE_OK (etype) == 0 || ETYPE_IS_STRING(etype) == 0)
- return ASN1_VALUE_NOT_VALID;
-
- /* doesn't handle constructed classes */
- if (ETYPE_CLASS (etype) != ASN1_CLASS_UNIVERSAL)
- return ASN1_VALUE_NOT_VALID;
-
- p = der;
- ret = asn1_get_tag_der (p, der_len, &class, &tag_len, &tag);
- if (ret != ASN1_SUCCESS)
- return ret;
-
- if (class != ETYPE_CLASS (etype) || tag != ETYPE_TAG (etype))
- {
- warn();
- return ASN1_DER_ERROR;
- }
-
- p += tag_len;
- der_len -= tag_len;
- if (der_len <= 0)
- return ASN1_DER_ERROR;
-
- ret = asn1_get_length_der (p, der_len, &len_len);
- if (ret < 0)
- return ASN1_DER_ERROR;
-
- p += len_len;
- der_len -= len_len;
- if (der_len <= 0)
- return ASN1_DER_ERROR;
-
- *str_len = ret;
- *str = p;
-
- return ASN1_SUCCESS;
+ return _asn1_decode_simple_der(etype, der, _der_len, str, str_len, 1);
}
static int append(uint8_t **dst, unsigned *dst_size, const unsigned char *src, unsigned src_size)
@@ -2223,25 +2107,27 @@
return ASN1_SUCCESS;
}
-/**
- * asn1_decode_simple_ber:
+/*-
+ * _asn1_decode_simple_ber:
* @etype: The type of the string to be encoded (ASN1_ETYPE_)
* @der: the encoded string
* @_der_len: the bytes of the encoded string
* @str: a pointer to the data
* @str_len: the length of the data
* @ber_len: the total length occupied by BER (may be %NULL)
+ * @have_tag: whether a DER tag is included
*
* Decodes a BER encoded type. The output is an allocated value
* of the data. This decodes BER STRINGS only. Other types are
* decoded as DER.
*
* Returns: %ASN1_SUCCESS if successful or an error value.
- **/
-int
-asn1_decode_simple_ber (unsigned int etype, const unsigned char *der,
+ -*/
+static int
+_asn1_decode_simple_ber (unsigned int etype, const unsigned char *der,
unsigned int _der_len, unsigned char **str,
- unsigned int *str_len, unsigned int *ber_len)
+ unsigned int *str_len, unsigned int *ber_len,
+ unsigned have_tag)
{
int tag_len, len_len;
const unsigned char *p;
@@ -2271,32 +2157,37 @@
}
/* doesn't handle constructed + definite classes */
- if (ETYPE_CLASS (tag_type) != ASN1_CLASS_UNIVERSAL)
+ class = ETYPE_CLASS (tag_type);
+ if (class != ASN1_CLASS_UNIVERSAL)
{
warn();
return ASN1_VALUE_NOT_VALID;
}
p = der;
- result = asn1_get_tag_der (p, der_len, &class, &tag_len, &tag);
- if (result != ASN1_SUCCESS)
+
+ if (have_tag)
{
- warn();
- return result;
+ result = asn1_get_tag_der (p, der_len, &class, &tag_len, &tag);
+ if (result != ASN1_SUCCESS)
+ {
+ warn();
+ return result;
+ }
+
+ if (tag != ETYPE_TAG (tag_type))
+ {
+ warn();
+ return ASN1_DER_ERROR;
+ }
+
+ p += tag_len;
+
+ DECR_LEN(der_len, tag_len);
+
+ if (ber_len) *ber_len += tag_len;
}
- if (tag != ETYPE_TAG (tag_type))
- {
- warn();
- return ASN1_DER_ERROR;
- }
-
- p += tag_len;
-
- DECR_LEN(der_len, tag_len);
-
- if (ber_len) *ber_len += tag_len;
-
/* indefinite constructed */
if (class == ASN1_CLASS_STRUCTURED && ETYPE_IS_STRING(tag_type))
{
@@ -2379,7 +2270,7 @@
}
/* non-string values are decoded as DER */
- result = asn1_decode_simple_der(tag_type, der, _der_len, &cout, &out_len);
+ result = _asn1_decode_simple_der(tag_type, der, _der_len, &cout, &out_len, have_tag);
if (result != ASN1_SUCCESS)
{
warn();
@@ -2409,3 +2300,26 @@
free(total);
return result;
}
+
+/**
+ * asn1_decode_simple_ber:
+ * @etype: The type of the string to be encoded (ASN1_ETYPE_)
+ * @der: the encoded string
+ * @_der_len: the bytes of the encoded string
+ * @str: a pointer to the data
+ * @str_len: the length of the data
+ * @ber_len: the total length occupied by BER (may be %NULL)
+ *
+ * Decodes a BER encoded type. The output is an allocated value
+ * of the data. This decodes BER STRINGS only. Other types are
+ * decoded as DER.
+ *
+ * Returns: %ASN1_SUCCESS if successful or an error value.
+ **/
+int
+asn1_decode_simple_ber (unsigned int etype, const unsigned char *der,
+ unsigned int _der_len, unsigned char **str,
+ unsigned int *str_len, unsigned int *ber_len)
+{
+ return _asn1_decode_simple_ber(etype, der, _der_len, str, str_len, ber_len, 1);
+}
