transport.c: Add some comments
@@ -122,7 +122,8 @@ debugdump(LIBSSH2_SESSION * session,
#endif
-/* decrypt() decrypts 'len' bytes from 'source' to 'dest'.
+/* decrypt() decrypts 'len' bytes from 'source' to 'dest' in units of
+ * blocksize.
*
* returns 0 on success and negative on failure
*/
@@ -274,13 +275,17 @@ int _libssh2_transport_read(LIBSSH2_SESSION * session)
{
int rc;
struct transportpacket *p = &session->packet;
- int remainbuf;
- int remainpack;
- int numbytes;
- int numdecrypt;
- unsigned char block[MAX_BLOCKSIZE];
- int blocksize;
- int encrypted = 1;
+ int remainpack; /* how much there is left to add to the current payload
+ package */
+ int remainbuf; /* how much data there is remaining in the buffer to deal
+ with before we should read more from the network */
+ int numbytes; /* how much data to deal with from the buffer on this
+ iteration through the loop */
+ int numdecrypt; /* number of bytes to decrypt this iteration */
+ unsigned char block[MAX_BLOCKSIZE]; /* working block buffer */
+ int blocksize; /* minimum number of bytes we need before we can
+ use them */
+ int encrypted = 1; /* whether the packet is encrypted or not */
/* default clear the bit */
session->socket_block_directions &= ~LIBSSH2_SESSION_BLOCK_INBOUND;
@@ -400,7 +405,9 @@ int _libssh2_transport_read(LIBSSH2_SESSION * session)
numbytes = remainbuf;
if(!p->total_num) {
- size_t total_num;
+ size_t total_num; /* the number of bytes following the initial
+ (5 bytes) packet length and padding length
+ fields */
/* No payload package area allocated yet. To know the
size of this payload, we need to decrypt the first
