/*
This file is part of GNUnet.
- (C) 2009 Christian Grothoff (and other contributing authors)
+ Copyright (C) 2009-2011 GNUnet e.V.
GNUnet is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
- by the Free Software Foundation; either version 2, or (at your
+ by the Free Software Foundation; either version 3, or (at your
option) any later version.
GNUnet is distributed in the hope that it will be useful, but
You should have received a copy of the GNU General Public License
along with GNUnet; see the file COPYING. If not, write to the
- Free Software Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA.
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ Boston, MA 02110-1301, USA.
*/
/**
* @file fs/fs_tree.c
* @see http://gnunet.org/encoding.php3
* @author Krista Bennett
* @author Christian Grothoff
- *
- * TODO:
- * - decide if this API should be made public (gnunet_fs_service.h)
- * or remain "internal" (but with exported symbols?)
*/
#include "platform.h"
#include "fs_tree.h"
-#define DEBUG_TREE GNUNET_NO
/**
* Context for an ECRS-based file encoder that computes
* Global FS context.
*/
struct GNUNET_FS_Handle *h;
-
+
/**
* Closure for all callbacks.
*/
/**
* Function to call once we're done with processing.
*/
- GNUNET_SCHEDULER_Task cont;
-
+ GNUNET_SCHEDULER_TaskCallback cont;
+
/**
* Set to an error message (if we had an error).
*/
* Set to the URI (upon successful completion)
*/
struct GNUNET_FS_Uri *uri;
-
+
/**
* Overall file size.
*/
uint64_t publish_offset;
/**
- * How deep are we?
+ * How deep are we? Depth 0 is for the DBLOCKs.
*/
unsigned int current_depth;
/**
- * How deep is the tree?
+ * How deep is the tree? Always > 0.
*/
unsigned int chk_tree_depth;
* In-memory cache of the current CHK tree.
* This struct will contain the CHK values
* from the root to the currently processed
- * node in the tree as identified by
+ * node in the tree as identified by
* "current_depth" and "publish_offset".
* The "chktree" will be initially NULL,
* then allocated to a sufficient number of
*/
struct ContentHashKey *chk_tree;
+ /**
+ * Are we currently in 'GNUNET_FS_tree_encoder_next'?
+ * Flag used to prevent recursion.
+ */
+ int in_next;
};
* Compute the depth of the CHK tree.
*
* @param flen file length for which to compute the depth
- * @return depth of the tree
+ * @return depth of the tree, always > 0. A depth of 1 means only a DBLOCK.
*/
unsigned int
GNUNET_FS_compute_depth (uint64_t flen)
treeDepth = 1;
fl = DBLOCK_SIZE;
while (fl < flen)
+ {
+ treeDepth++;
+ if (fl * CHK_PER_INODE < fl)
{
- treeDepth++;
- if (fl * CHK_PER_INODE < fl)
- {
- /* integer overflow, this is a HUGE file... */
- return treeDepth;
- }
- fl = fl * CHK_PER_INODE;
+ /* integer overflow, this is a HUGE file... */
+ return treeDepth;
}
+ fl = fl * CHK_PER_INODE;
+ }
return treeDepth;
}
/**
- * Initialize a tree encoder. This function will call "proc" and
+ * Calculate how many bytes of payload a block tree of the given
+ * depth MAY correspond to at most (this function ignores the fact that
+ * some blocks will only be present partially due to the total file
+ * size cutting some blocks off at the end).
+ *
+ * @param depth depth of the block. depth==0 is a DBLOCK.
+ * @return number of bytes of payload a subtree of this depth may correspond to
+ */
+uint64_t
+GNUNET_FS_tree_compute_tree_size (unsigned int depth)
+{
+ uint64_t rsize;
+ unsigned int i;
+
+ rsize = DBLOCK_SIZE;
+ for (i = 0; i < depth; i++)
+ rsize *= CHK_PER_INODE;
+ return rsize;
+}
+
+
+/**
+ * Compute the size of the current IBLOCK. The encoder is
+ * triggering the calculation of the size of an IBLOCK at the
+ * *end* (hence end_offset) of its construction. The IBLOCK
+ * maybe a full or a partial IBLOCK, and this function is to
+ * calculate how long it should be.
+ *
+ * @param depth depth of the IBlock in the tree, 0 would be a DBLOCK,
+ * must be > 0 (this function is for IBLOCKs only!)
+ * @param end_offset current offset in the payload (!) of the overall file,
+ * must be > 0 (since this function is called at the
+ * end of a block).
+ * @return size of the corresponding IBlock
+ */
+static uint16_t
+GNUNET_FS_tree_compute_iblock_size (unsigned int depth, uint64_t end_offset)
+{
+ unsigned int ret;
+ uint64_t mod;
+ uint64_t bds;
+
+ GNUNET_assert (depth > 0);
+ GNUNET_assert (end_offset > 0);
+ bds = GNUNET_FS_tree_compute_tree_size (depth);
+ mod = end_offset % bds;
+ if (0 == mod)
+ {
+ /* we were triggered at the end of a full block */
+ ret = CHK_PER_INODE;
+ }
+ else
+ {
+ /* we were triggered at the end of the file */
+ bds /= CHK_PER_INODE;
+ ret = mod / bds;
+ if (0 != mod % bds)
+ ret++;
+ }
+ return (uint16_t) (ret * sizeof (struct ContentHashKey));
+}
+
+
+/**
+ * Compute how many bytes of data should be stored in
+ * the specified block.
+ *
+ * @param fsize overall file size, must be > 0.
+ * @param offset offset in the original data corresponding
+ * to the beginning of the tree induced by the block;
+ * must be <= fsize
+ * @param depth depth of the node in the tree, 0 for DBLOCK
+ * @return number of bytes stored in this node
+ */
+size_t
+GNUNET_FS_tree_calculate_block_size (uint64_t fsize, uint64_t offset,
+ unsigned int depth)
+{
+ size_t ret;
+ uint64_t rsize;
+ uint64_t epos;
+ unsigned int chks;
+
+ GNUNET_assert (fsize > 0);
+ GNUNET_assert (offset <= fsize);
+ if (depth == 0)
+ {
+ ret = DBLOCK_SIZE;
+ if ((offset + ret > fsize) || (offset + ret < offset))
+ ret = (size_t) (fsize - offset);
+ return ret;
+ }
+
+ rsize = GNUNET_FS_tree_compute_tree_size (depth - 1);
+ epos = offset + rsize * CHK_PER_INODE;
+ if ((epos < offset) || (epos > fsize))
+ epos = fsize;
+ /* round up when computing #CHKs in our IBlock */
+ chks = (epos - offset + rsize - 1) / rsize;
+ GNUNET_assert (chks <= CHK_PER_INODE);
+ return chks * sizeof (struct ContentHashKey);
+}
+
+
+/**
+ * Initialize a tree encoder. This function will call @a proc and
* "progress" on each block in the tree. Once all blocks have been
- * processed, "cont" will be scheduled. The "reader" will be called
+ * processed, "cont" will be scheduled. The @a reader will be called
* to obtain the (plaintext) blocks for the file. Note that this
- * function will not actually call "proc". The client must
- * call "GNUNET_FS_tree_encoder_next" to trigger encryption (and
- * calling of "proc") for the each block.
+ * function will not actually call @a proc. The client must
+ * call #GNUNET_FS_tree_encoder_next to trigger encryption (and
+ * calling of @a proc) for the each block.
*
* @param h the global FS context
* @param size overall size of the file to encode
* @param cls closure for reader, proc, progress and cont
* @param reader function to call to read plaintext data
* @param proc function to call on each encrypted block
- * @param progress function to call with progress information
+ * @param progress function to call with progress information
* @param cont function to call when done
*/
struct GNUNET_FS_TreeEncoder *
-GNUNET_FS_tree_encoder_create (struct GNUNET_FS_Handle *h,
- uint64_t size,
- void *cls,
+GNUNET_FS_tree_encoder_create (struct GNUNET_FS_Handle *h, uint64_t size,
+ void *cls,
GNUNET_FS_DataReader reader,
- GNUNET_FS_TreeBlockProcessor proc,
- GNUNET_FS_TreeProgressCallback progress,
- GNUNET_SCHEDULER_Task cont)
+ GNUNET_FS_TreeBlockProcessor proc,
+ GNUNET_FS_TreeProgressCallback progress,
+ GNUNET_SCHEDULER_TaskCallback cont)
{
struct GNUNET_FS_TreeEncoder *te;
-
- GNUNET_assert (size > 0);
- te = GNUNET_malloc (sizeof (struct GNUNET_FS_TreeEncoder));
+
+ te = GNUNET_new (struct GNUNET_FS_TreeEncoder);
te->h = h;
te->size = size;
te->cls = cls;
te->progress = progress;
te->cont = cont;
te->chk_tree_depth = GNUNET_FS_compute_depth (size);
- te->current_depth = te->chk_tree_depth;
- te->chk_tree = GNUNET_malloc (te->chk_tree_depth *
- CHK_PER_INODE *
- sizeof (struct ContentHashKey));
+ te->chk_tree
+ = GNUNET_new_array (te->chk_tree_depth * CHK_PER_INODE,
+ struct ContentHashKey);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Created tree encoder for file with %llu bytes and depth %u\n",
+ (unsigned long long) size,
+ te->chk_tree_depth);
return te;
}
-/**
- * Compute the size of the current IBlock.
- *
- * @param height height of the IBlock in the tree (aka overall
- * number of tree levels minus depth); 0 == DBlock
- * @param offset current offset in the overall file
- * @return size of the corresponding IBlock
- */
-static uint16_t
-compute_iblock_size (unsigned int height,
- uint64_t offset)
-{
- unsigned int ret;
- unsigned int i;
- uint64_t mod;
- uint64_t bds;
-
- GNUNET_assert (height > 0);
- bds = DBLOCK_SIZE; /* number of bytes each CHK at level "i"
- corresponds to */
- for (i=0;i<height;i++)
- bds *= CHK_PER_INODE;
- mod = offset % bds;
- if (0 == mod)
- {
- /* we were triggered at the end of a full block */
- ret = CHK_PER_INODE;
- }
- else
- {
- /* we were triggered at the end of the file */
- bds /= CHK_PER_INODE;
- ret = mod / bds;
- if (0 != mod % bds)
- ret++;
- }
- return (uint16_t) (ret * sizeof(struct ContentHashKey));
-}
-
-
/**
* Compute the offset of the CHK for the
* current block in the IBlock above.
*
- * @param height height of the IBlock in the tree (aka overall
+ * @param depth depth of the IBlock in the tree (aka overall
* number of tree levels minus depth); 0 == DBlock
- * @param offset current offset in the overall file
+ * @param end_offset current offset in the overall file,
+ * at the *beginning* of the block for DBLOCKs (depth==0),
+ * otherwise at the *end* of the block (exclusive)
* @return (array of CHKs') offset in the above IBlock
*/
static unsigned int
-compute_chk_offset (unsigned int height,
- uint64_t offset)
+compute_chk_offset (unsigned int depth, uint64_t end_offset)
{
uint64_t bds;
unsigned int ret;
- unsigned int i;
- bds = DBLOCK_SIZE; /* number of bytes each CHK at level "i"
- corresponds to */
- for (i=0;i<height;i++)
- bds *= CHK_PER_INODE;
- ret = offset / bds;
- return ret % CHK_PER_INODE;
+ bds = GNUNET_FS_tree_compute_tree_size (depth);
+ if (depth > 0)
+ end_offset--; /* round down since for depth > 0 offset is at the END of the block */
+ ret = end_offset / bds;
+ return ret % CHK_PER_INODE;
}
/**
- * Encrypt the next block of the file (and
- * call proc and progress accordingly; or
- * of course "cont" if we have already completed
+ * Encrypt the next block of the file (and call proc and progress
+ * accordingly; or of course "cont" if we have already completed
* encoding of the entire file).
*
* @param te tree encoder to use
*/
-void GNUNET_FS_tree_encoder_next (struct GNUNET_FS_TreeEncoder * te)
+void
+GNUNET_FS_tree_encoder_next (struct GNUNET_FS_TreeEncoder *te)
{
struct ContentHashKey *mychk;
const void *pt_block;
uint16_t pt_size;
char iob[DBLOCK_SIZE];
char enc[DBLOCK_SIZE];
- struct GNUNET_CRYPTO_AesSessionKey sk;
- struct GNUNET_CRYPTO_AesInitializationVector iv;
+ struct GNUNET_CRYPTO_SymmetricSessionKey sk;
+ struct GNUNET_CRYPTO_SymmetricInitializationVector iv;
unsigned int off;
- if (te->current_depth == te->chk_tree_depth)
- {
- pt_size = GNUNET_MIN(DBLOCK_SIZE,
- te->size - te->publish_offset);
- if (pt_size !=
- te->reader (te->cls,
- te->publish_offset,
- pt_size,
- iob,
- &te->emsg))
- {
- GNUNET_SCHEDULER_add_continuation (te->h->sched,
- te->cont,
- te->cls,
- GNUNET_SCHEDULER_REASON_TIMEOUT);
- return;
- }
- pt_block = iob;
- }
- else
- {
- pt_size = compute_iblock_size (te->chk_tree_depth - te->current_depth,
- te->publish_offset);
- pt_block = &te->chk_tree[te->current_depth *
- CHK_PER_INODE];
- }
+ GNUNET_assert (GNUNET_NO == te->in_next);
+ te->in_next = GNUNET_YES;
+ if (te->chk_tree_depth == te->current_depth)
+ {
+ off = CHK_PER_INODE * (te->chk_tree_depth - 1);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "TE done, reading CHK `%s' from %u\n",
+ GNUNET_h2s (&te->chk_tree[off].query), off);
+ te->uri = GNUNET_new (struct GNUNET_FS_Uri);
+ te->uri->type = GNUNET_FS_URI_CHK;
+ te->uri->data.chk.chk = te->chk_tree[off];
+ te->uri->data.chk.file_length = GNUNET_htonll (te->size);
+ te->in_next = GNUNET_NO;
+ te->cont (te->cls);
+ return;
+ }
if (0 == te->current_depth)
+ {
+ /* read DBLOCK */
+ pt_size = GNUNET_MIN (DBLOCK_SIZE, te->size - te->publish_offset);
+ if (pt_size !=
+ te->reader (te->cls, te->publish_offset, pt_size, iob, &te->emsg))
{
- te->uri = GNUNET_malloc (sizeof(struct GNUNET_FS_Uri));
- te->uri->type = chk;
- te->uri->data.chk.chk = te->chk_tree[0];
- te->uri->data.chk.file_length = GNUNET_htonll (te->size);
- GNUNET_SCHEDULER_add_continuation (te->h->sched,
- te->cont,
- te->cls,
- GNUNET_SCHEDULER_REASON_PREREQ_DONE);
+ te->in_next = GNUNET_NO;
+ te->cont (te->cls);
return;
}
- off = compute_chk_offset (te->chk_tree_depth - te->current_depth,
- te->publish_offset);
-#if DEBUG_TREE
+ pt_block = iob;
+ }
+ else
+ {
+ pt_size =
+ GNUNET_FS_tree_compute_iblock_size (te->current_depth,
+ te->publish_offset);
+ pt_block = &te->chk_tree[(te->current_depth - 1) * CHK_PER_INODE];
+ }
+ off = compute_chk_offset (te->current_depth, te->publish_offset);
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "TE is at offset %llu and depth %u with block size %u and target-CHK-offset %u\n",
- (unsigned long long) te->publish_offset,
- te->current_depth,
- (unsigned int) pt_size,
- (unsigned int) off);
-#endif
- mychk = &te->chk_tree[(te->current_depth-1)*CHK_PER_INODE+off];
+ "TE is at offset %llu and depth %u with block size %u and target-CHK-offset %u\n",
+ (unsigned long long) te->publish_offset, te->current_depth,
+ (unsigned int) pt_size, (unsigned int) off);
+ mychk = &te->chk_tree[te->current_depth * CHK_PER_INODE + off];
GNUNET_CRYPTO_hash (pt_block, pt_size, &mychk->key);
GNUNET_CRYPTO_hash_to_aes_key (&mychk->key, &sk, &iv);
- GNUNET_CRYPTO_aes_encrypt (pt_block,
- pt_size,
- &sk,
- &iv,
- enc);
+ GNUNET_CRYPTO_symmetric_encrypt (pt_block, pt_size, &sk, &iv, enc);
GNUNET_CRYPTO_hash (enc, pt_size, &mychk->query);
-#if DEBUG_TREE
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
- "TE calculates query to be `%s'\n",
- GNUNET_h2s (&mychk->query));
-#endif
+ "TE calculates query to be `%s', stored at %u\n",
+ GNUNET_h2s (&mychk->query),
+ te->current_depth * CHK_PER_INODE + off);
if (NULL != te->proc)
- te->proc (te->cls,
- &mychk->query,
- te->publish_offset,
- (te->current_depth == te->chk_tree_depth)
- ? GNUNET_DATASTORE_BLOCKTYPE_DBLOCK
- : GNUNET_DATASTORE_BLOCKTYPE_IBLOCK,
- enc,
- pt_size);
+ te->proc (te->cls, mychk, te->publish_offset, te->current_depth,
+ (0 ==
+ te->current_depth) ? GNUNET_BLOCK_TYPE_FS_DBLOCK :
+ GNUNET_BLOCK_TYPE_FS_IBLOCK, enc, pt_size);
if (NULL != te->progress)
- te->progress (te->cls,
- te->publish_offset,
- pt_block,
- pt_size,
- te->current_depth);
- if (te->current_depth == te->chk_tree_depth)
- {
- te->publish_offset += pt_size;
- if ( (te->publish_offset == te->size) ||
- (0 == te->publish_offset % (CHK_PER_INODE * DBLOCK_SIZE) ) )
- te->current_depth--;
- }
+ te->progress (te->cls, te->publish_offset, pt_block, pt_size,
+ te->current_depth);
+ if (0 == te->current_depth)
+ {
+ te->publish_offset += pt_size;
+ if ((te->publish_offset == te->size) ||
+ (0 == te->publish_offset % (CHK_PER_INODE * DBLOCK_SIZE)))
+ te->current_depth++;
+ }
else
- {
- if ( (off == CHK_PER_INODE) ||
- (te->publish_offset == te->size) )
- te->current_depth--;
- else
- te->current_depth = te->chk_tree_depth;
- }
+ {
+ if ((off == CHK_PER_INODE) || (te->publish_offset == te->size))
+ te->current_depth++;
+ else
+ te->current_depth = 0;
+ }
+ te->in_next = GNUNET_NO;
+}
+
+
+/**
+ * Get the resulting URI from the encoding.
+ *
+ * @param te the tree encoder to clean up
+ * @return uri set to the resulting URI (if encoding finished), NULL otherwise
+ */
+struct GNUNET_FS_Uri *
+GNUNET_FS_tree_encoder_get_uri (struct GNUNET_FS_TreeEncoder *te)
+{
+ if (NULL != te->uri)
+ return GNUNET_FS_uri_dup (te->uri);
+ return NULL;
}
/**
* Clean up a tree encoder and return information
- * about the resulting URI or an error message.
- *
+ * about possible errors.
+ *
* @param te the tree encoder to clean up
- * @param uri set to the resulting URI (if encoding finished)
* @param emsg set to an error message (if an error occured
* within the tree encoder; if this function is called
* prior to completion and prior to an internal error,
- * both "*uri" and "*emsg" will be set to NULL).
+ * both "*emsg" will be set to NULL).
*/
-void GNUNET_FS_tree_encoder_finish (struct GNUNET_FS_TreeEncoder * te,
- struct GNUNET_FS_Uri **uri,
- char **emsg)
+void
+GNUNET_FS_tree_encoder_finish (struct GNUNET_FS_TreeEncoder *te,
+ char **emsg)
{
- if (uri != NULL)
- *uri = te->uri;
- else
- if (NULL != te->uri)
- GNUNET_FS_uri_destroy (te->uri);
+ if (NULL != te->reader)
+ {
+ (void) te->reader (te->cls, UINT64_MAX, 0, 0, NULL);
+ te->reader = NULL;
+ }
+ GNUNET_assert (GNUNET_NO == te->in_next);
+ if (NULL != te->uri)
+ GNUNET_FS_uri_destroy (te->uri);
if (emsg != NULL)
*emsg = te->emsg;
else
projects / oweals / gnunet.git / blobdiff