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-rw-r--r--epan/proto.c240
-rw-r--r--epan/proto.h2
-rw-r--r--epan/tvbuff.c115
-rw-r--r--epan/tvbuff.h2
4 files changed, 199 insertions, 160 deletions
diff --git a/epan/proto.c b/epan/proto.c
index e2f0f79e9e..5cfaee7b3d 100644
--- a/epan/proto.c
+++ b/epan/proto.c
@@ -5589,152 +5589,43 @@ proto_tree_add_bits(proto_tree *tree, int hf_index, tvbuff_t *tvb, gint bit_offs
/*
* This function will dissect a sequence of bits that does not need to be byte aligned the bits
* set vill be shown in the tree as ..10 10.. and the integer value returned if return_value is set.
- * Offset should be given in bits. Currently only up to 24 unaligned bits can be handled.
+ * Offset should be given in bits from the start of the tvb.
*/
proto_item *
-proto_tree_add_bits_ret_val(proto_tree *tree, int hf_index, tvbuff_t *tvb, gint bit_offset, gint no_of_bits, guint32 *return_value, gboolean little_endian)
+proto_tree_add_bits_ret_val(proto_tree *tree, int hf_index, tvbuff_t *tvb, gint bit_offset, gint no_of_bits, guint64 *return_value, gboolean little_endian)
{
- gint offset;
- guint length;
- guint bit_length;
+ gint offset;
+ guint length;
+ guint8 tot_no_bits;
+ guint8 remaining_bits;
+ guint64 mask = 0,tmp;
char *str;
header_field_info *hf_field;
- guint32 value = 0;
+ guint64 value = 0;
int bit;
- guint32 mask = 0, tmp;
- gboolean is_bytealigned = FALSE;
- guint8 mask8 = 0xff;
- guint16 mask16 = 0xffff;
- guint32 mask24 = 0xffffff;
- guint32 mask32 = 0xffffffff;
- guint8 shift;
int i;
- if((bit_offset&0x7)==0)
- is_bytealigned = TRUE;
-
hf_field = proto_registrar_get_nth(hf_index);
+ /* Byte align offset */
offset = bit_offset>>3;
- bit_length = ((bit_offset&0x7)+no_of_bits);
- length = bit_length >>3;
- if((bit_length&0x7)!=0)
- length = length +1;
-
- if (no_of_bits < 2){
- /* Single bit */
- mask8 = mask8 >>(bit_offset&0x7);
- value = tvb_get_guint8(tvb,offset) & mask8;
- mask = 0x80;
- shift = 8-((bit_offset + no_of_bits)&0x7);
- if (shift<8){
- value = value >> shift;
- mask = mask >> shift;
- }
- }else if(no_of_bits < 9){
- /* One or 2 bytes */
- if(length == 1){
- /* Spans 1 byte */
- mask8 = mask8>>(bit_offset&0x7);
- value = tvb_get_guint8(tvb,offset)&mask8;
- mask = 0x80;
- }else{
- /* Spans 2 bytes */
- mask16 = mask16>>(bit_offset&0x7);
- if(little_endian){
- value=tvb_get_letohs(tvb, offset);
- } else {
- value=tvb_get_ntohs(tvb, offset);
- }
- mask = 0x8000;
- }
- shift = 8-((bit_offset + no_of_bits)&0x7);
- if (shift<8){
- value = value >> shift;
- mask = mask >> shift;
- }
-
- }else if (no_of_bits < 17){
- /* 2 or 3 bytes */
- if(length == 2){
- /* Spans 2 bytes */
- mask16 = mask16>>(bit_offset&0x7);
- if(little_endian){
- value=tvb_get_letohs(tvb, offset);
- } else {
- value=tvb_get_ntohs(tvb, offset);
- }
- mask = 0x8000;
- }else{
- /* Spans 3 bytes */
- mask24 = mask24>>(bit_offset&0x7);
- if(little_endian){
- value=tvb_get_letoh24(tvb, offset);
- } else {
- value=tvb_get_ntoh24(tvb, offset);
- }
- mask = 0x800000;
- }
- shift = 8-((bit_offset + no_of_bits)&0x7);
- if (shift<8){
- value = value >> shift;
- mask = mask >> shift;
- }
- }else if (no_of_bits < 25){
- /* 3 or 4 bytes */
- if(length == 3){
- /* Spans 3 bytes */
- mask24 = mask24>>(bit_offset&0x7);
- if(little_endian){
- value=tvb_get_letoh24(tvb, offset);
- } else {
- value=tvb_get_ntoh24(tvb, offset);
- }
- mask = 0x800000;
- }else{
- /* Spans 4 bytes */
- mask32 = mask32>>(bit_offset&0x7);
- if(little_endian){
- value=tvb_get_letohl(tvb, offset);
- } else {
- value=tvb_get_ntohl(tvb, offset);
- }
- mask = 0x80000000;
- }
- shift = 8-((bit_offset + no_of_bits)&0x7);
- if (shift<8){
- value = value >> shift;
- mask = mask >> shift;
- }
- }else if (no_of_bits < 33){
- /* 4 or 5 bytes */
- if(length == 4){
- /* Spans 4 bytes */
- mask32 = mask32>>(bit_offset&0x7);
- if(little_endian){
- value=tvb_get_letohl(tvb, offset);
- } else {
- value=tvb_get_ntohl(tvb, offset);
- }
- mask = 0x80000000;
- }else{
- /* Spans 5 bytes
- * Does not handle unaligned bits over 24
- */
- DISSECTOR_ASSERT_NOT_REACHED();
- }
- shift = 8-((bit_offset + no_of_bits)&0x7);
- if (shift<8){
- value = value >> shift;
- mask = mask >> shift;
- }
+ /*
+ * Calculate the number of octets used to hold the bits
+ */
+ tot_no_bits = ((bit_offset&0x7)+no_of_bits);
+ length = tot_no_bits>>3;
+ remaining_bits = tot_no_bits % 8;
+ if ((remaining_bits)!=0)
+ length++;
- }else{
- DISSECTOR_ASSERT_NOT_REACHED();
- }
+
+ value = tvb_get_bits(tvb, bit_offset, no_of_bits, little_endian);
+
+ mask = 1;
+ mask = mask << (no_of_bits-1);
/* prepare the string */
str=ep_alloc(256);
@@ -5744,7 +5635,6 @@ proto_tree_add_bits_ret_val(proto_tree *tree, int hf_index, tvbuff_t *tvb, gint
strcat(str, " ");
}
strcat(str,".");
- mask = mask>>1;
}
/* read the bits for the int */
for(i=0;i<no_of_bits;i++){
@@ -5779,48 +5669,80 @@ proto_tree_add_bits_ret_val(proto_tree *tree, int hf_index, tvbuff_t *tvb, gint
strcat(str," = ");
strcat(str,hf_field->name);
- if (hf_field->type == FT_BOOLEAN){
+ switch(hf_field->type){
+ case FT_BOOLEAN:
/* Boolean field */
if (hf_field->strings) {
const true_false_string *tfstring = &tfs_true_false;
tfstring = (const struct true_false_string*) hf_field->strings;
- return proto_tree_add_boolean_format(tree, hf_index, tvb, offset, length, value,
+ return proto_tree_add_boolean_format(tree, hf_index, tvb, offset, length, (guint32)value,
"%s: %s",
str,
- value ? tfstring->true_string : tfstring->false_string);
+ (guint32)value ? tfstring->true_string : tfstring->false_string);
}else{
- return proto_tree_add_boolean_format(tree, hf_index, tvb, offset, length, value,
+ return proto_tree_add_boolean_format(tree, hf_index, tvb, offset, length, (guint32)value,
"%s: %u",
str,
- value);
+ (guint32)value);
}
- }
- /* 1 - 32 bits field */
- if (hf_field->strings) {
- return proto_tree_add_uint_format(tree, hf_index, tvb, offset, length, value,
- "%s: %s (%u)",
- str,
- val_to_str(value, cVALS(hf_field->strings), "Unknown "),
- value);
- }
- switch(hf_field->display){
- case BASE_DEC:
- return proto_tree_add_uint_format(tree, hf_index, tvb, offset, length, value,
- "%s: %u",
- str,
- value);
break;
- case BASE_HEX:
- return proto_tree_add_uint_format(tree, hf_index, tvb, offset, length, value,
- "%s: 0x%x",
- str,
- value);
+ case FT_UINT8:
+ case FT_UINT16:
+ case FT_UINT24:
+ case FT_UINT32:
+ /* 1 - 32 bits field */
+ if (hf_field->strings) {
+ return proto_tree_add_uint_format(tree, hf_index, tvb, offset, length, (guint32)value,
+ "%s: %s (%u)",
+ str,
+ val_to_str((guint32)value, cVALS(hf_field->strings), "Unknown "),
+ (guint32)value);
+ break;
+ }
+ switch(hf_field->display){
+ case BASE_DEC:
+ return proto_tree_add_uint_format(tree, hf_index, tvb, offset, length, (guint32)value,
+ "%s: %u",
+ str,
+ (guint32)value);
+ break;
+ case BASE_HEX:
+ return proto_tree_add_uint_format(tree, hf_index, tvb, offset, length, (guint32)value,
+ "%s: 0x%x",
+ str,
+ (guint32)value);
+ break;
+ default:
+ DISSECTOR_ASSERT_NOT_REACHED();
+ return NULL;
+ break;
+ }
+ break;
+ case FT_UINT64:
+ switch(hf_field->display){
+ case BASE_DEC:
+ return proto_tree_add_uint64_format(tree, hf_index, tvb, offset, length, value,
+ "%s: %llu",
+ str,
+ value);
+ break;
+ case BASE_HEX:
+ return proto_tree_add_uint64_format(tree, hf_index, tvb, offset, length, value,
+ "%s: 0x%llx",
+ str,
+ value);
+ break;
+ default:
+ DISSECTOR_ASSERT_NOT_REACHED();
+ return NULL;
+ break;
+ }
break;
default:
DISSECTOR_ASSERT_NOT_REACHED();
return NULL;
- ;
+ break;
}
-} \ No newline at end of file
+}
diff --git a/epan/proto.h b/epan/proto.h
index cd43deeb0d..1f5b8a1c1b 100644
--- a/epan/proto.h
+++ b/epan/proto.h
@@ -1597,7 +1597,7 @@ proto_tree_add_bits(proto_tree *tree, int hf_index, tvbuff_t *tvb, gint bit_offs
@return the newly created item */
extern proto_item *
-proto_tree_add_bits_ret_val(proto_tree *tree, int hf_index, tvbuff_t *tvb, gint bit_offset, gint no_of_bits, guint32 *return_value, gboolean little_endian);
+proto_tree_add_bits_ret_val(proto_tree *tree, int hf_index, tvbuff_t *tvb, gint bit_offset, gint no_of_bits, guint64 *return_value, gboolean little_endian);
#ifdef __cplusplus
}
diff --git a/epan/tvbuff.c b/epan/tvbuff.c
index 4ebc655062..2497ac1752 100644
--- a/epan/tvbuff.c
+++ b/epan/tvbuff.c
@@ -1446,6 +1446,121 @@ tvb_get_guid(tvbuff_t *tvb, gint offset, e_guid_t *guid, gboolean little_endian)
}
}
+static const guint8 bit_mask[] = {
+ 0xff,
+ 0x7f,
+ 0x3f,
+ 0x1f,
+ 0x0f,
+ 0x07,
+ 0x03,
+ 0x01
+};
+
+guint64
+tvb_get_bits(tvbuff_t *tvb, gint bit_offset, gint no_of_bits, gboolean little_endian)
+{
+
+ gint offset;
+ guint64 value = 0;
+ guint64 tempval = 0;
+ guint8 tot_no_bits;
+ guint8 num_octs;
+ guint8 shift;
+
+ if (no_of_bits>64)
+ DISSECTOR_ASSERT_NOT_REACHED();
+ if(little_endian){
+ DISSECTOR_ASSERT_NOT_REACHED();
+ /* This part is not implemented yet */
+ }
+
+ /* Byte align offset */
+ offset = bit_offset>>3;
+
+ /* Find out which mask to use for the most significant octet
+ * by convering bit_offset into the offset into the first
+ * fetched octet.
+ */
+ bit_offset = bit_offset & 0x7;
+ /* calculate number of octets to read */
+ tot_no_bits = bit_offset + no_of_bits;
+ num_octs = tot_no_bits>>3;
+ /* Calculate shift value for most significant bits in the first octet */
+ shift = 8 * (num_octs-1);
+
+
+ if ((tot_no_bits&0x7)!=0)
+ num_octs++;
+
+ tempval = tvb_get_guint8(tvb,offset)&bit_mask[bit_offset];
+ tempval = tempval << shift;
+
+ switch(num_octs){
+ case 1:
+ /* Total 8 bits */
+ value = tempval >> (8-no_of_bits);
+ break;
+ case 2:
+ /* Total 8 + 8 = 16*/
+ value = tempval | tvb_get_guint8(tvb,offset+1);
+ value = value >> (16 - tot_no_bits);
+ break;
+ case 3:
+ /* Total 8 + 16 = 24*/
+ value = tempval | tvb_get_ntohs(tvb,offset+1);
+ value = value >> (24 - tot_no_bits);
+ break;
+ case 4:
+ /* Total 8 + 24 = 32*/
+ value = tempval | tvb_get_ntoh24(tvb,offset+1);
+ value = value >> (32 - tot_no_bits);
+ break;
+ case 5:
+ /* total 8 + 32 = 40*/
+ value = tempval | (tvb_get_ntohl(tvb,offset+1));
+ value = value >> (40 - tot_no_bits);
+ break;
+ case 6:
+ /* total 8 + 32 + 8 = 48*/
+ tempval = tvb_get_ntohl(tvb,offset+1);
+ tempval = tempval <<8;
+ value = value | tempval;
+ value = value | tvb_get_guint8(tvb,offset+5);
+ value = value >> (48 - tot_no_bits);
+ break;
+ case 7:
+ /* total 8 + 32 + 16 = 56*/
+ tempval = tvb_get_ntohl(tvb,offset+1);
+ tempval = tempval <<16;
+ value = value | tempval;
+ value = value >> (56 - tot_no_bits);
+ break;
+ case 8:
+ /* total 8 + 32 + 24 = 64*/
+ tempval = tvb_get_ntohl(tvb,offset+1);
+ tempval = tempval <<24;
+ value = value | tempval;
+ value = value | tvb_get_ntoh24(tvb,offset+5);
+ value = value >> (64 - tot_no_bits);
+ break;
+ case 9:
+ /* total 8 +64 = 72
+ * If bit_offset = 7 and no_of_bits=64 nine bytes is needed.
+ */
+ value = tempval | tvb_get_ntoh64(tvb,offset+1);
+ value = value >> (72 - tot_no_bits);
+ break;
+ default:
+ DISSECTOR_ASSERT_NOT_REACHED();
+ return NULL;
+ break;
+ }
+
+ return value;
+
+}
+
/* Find first occurence of needle in tvbuff, starting at offset. Searches
* at most maxlength number of bytes; if maxlength is -1, searches to
* end of tvbuff.
diff --git a/epan/tvbuff.h b/epan/tvbuff.h
index e5b82508ec..4b75c4e647 100644
--- a/epan/tvbuff.h
+++ b/epan/tvbuff.h
@@ -336,6 +336,8 @@ extern void tvb_get_ntohguid(tvbuff_t *tvb, gint offset, e_guid_t *guid);
extern void tvb_get_letohguid(tvbuff_t *tvb, gint offset, e_guid_t *guid);
extern void tvb_get_guid(tvbuff_t *tvb, gint offset, e_guid_t *guid, gboolean little_endian);
+/* Fetch a specified number of bits from bit offset in a tvb */
+extern guint64 tvb_get_bits(tvbuff_t *tvb, gint bit_offset, gint no_of_bits, gboolean little_endian);
/** Returns target for convenience. Does not suffer from possible
* expense of tvb_get_ptr(), since this routine is smart enough
generated by cgit v1.2.1 (git 2.18.0) at 2024-07-12 12:39:37 +0000