Fixed bad bit shift and sign extension errors

src/libstrongswan/plugins/bliss/bliss_bitpacker.c

@@ -62,12 +62,19 @@ METHOD(bliss_bitpacker_t, get_bits, size_t,
 METHOD(bliss_bitpacker_t, write_bits, bool,
 	private_bliss_bitpacker_t *this, uint32_t value, size_t bits)
 {
+	if (bits == 0)
+	{
+		return TRUE;
+	}
 	if (bits > 32)
 	{
 		return FALSE;
 	}
+	if (bits < 32)
+	{
+		value &= (1 << bits) - 1;
+	}
 	this->bits += bits;
-	value &= (1 << bits) - 1;
 
 	while (TRUE)
 	{
@@ -152,7 +159,7 @@ METHOD(bliss_bitpacker_t, destroy, void,
 /**
  * See header.
  */
-bliss_bitpacker_t *bliss_bitpacker_create(size_t max_bits)
+bliss_bitpacker_t *bliss_bitpacker_create(uint16_t max_bits)
 {
 	private_bliss_bitpacker_t *this;
 

src/libstrongswan/plugins/bliss/bliss_bitpacker.h

@@ -73,7 +73,7 @@ struct bliss_bitpacker_t {
  *
  * @param max_bits		Total number of bits to be stored
  */
-bliss_bitpacker_t* bliss_bitpacker_create(size_t max_bits);
+bliss_bitpacker_t* bliss_bitpacker_create(uint16_t max_bits);
 
 /**
  * Create a bliss_bitpacker_t object for reading

src/libstrongswan/plugins/bliss/bliss_public_key.c

@@ -391,12 +391,15 @@ bool bliss_public_key_from_asn1(chunk_t object, bliss_param_set_t *set,
 {
 	bliss_bitpacker_t *packer;
 	uint32_t coefficient;
+	uint16_t needed_bits;
 	int i;
 
 	/* skip initial bit string octet defining unused bits */
 	object = chunk_skip(object, 1);
 
-	if (8 * object.len < set->n * set->q_bits)
+	needed_bits = set->n * set->q_bits;
+
+	if (8 * object.len < needed_bits)
 	{
 		return FALSE;
 	}