/**
* Clears a bit from bitArray if the respective usage
* counter on the disk hits/is zero.
*
* @param bitArray memory area to set the bit in
* @param bitIdx which bit to test
* @param fh A file to keep the 4bit address usage counters in
*/
static void
decrementBit (char *bitArray, unsigned int bitIdx,
const struct GNUNET_DISK_FileHandle *fh)
{
off_t fileslot;
unsigned char value;
unsigned int high;
unsigned int low;
unsigned int targetLoc;
if (GNUNET_DISK_handle_invalid (fh))
return; /* cannot decrement! */
/* Each char slot in the counter file holds two 4 bit counters */
fileslot = bitIdx / 2;
targetLoc = bitIdx % 2;
if (GNUNET_SYSERR == GNUNET_DISK_file_seek (fh, fileslot, GNUNET_DISK_SEEK_SET))
{
GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "seek");
return;
}
if (1 != GNUNET_DISK_file_read (fh, &value, 1))
value = 0;
low = value & 0xF;
high = (value & 0xF0) >> 4;
/* decrement, but once we have reached the max, never go back! */
if (targetLoc == 0)
{
if ((low > 0) && (low < 0xF))
low--;
if (low == 0)
{
clearBit (bitArray, bitIdx);
}
}
else
{
if ((high > 0) && (high < 0xF))
high--;
if (high == 0)
{
clearBit (bitArray, bitIdx);
}
}
value = ((high << 4) | low);
if (GNUNET_SYSERR == GNUNET_DISK_file_seek (fh, fileslot, GNUNET_DISK_SEEK_SET))
{
GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "seek");
return;
}
GNUNET_assert (1 == GNUNET_DISK_file_write (fh, &value, 1));
}
/**
* Creates a file filled with zeroes
*
* @param fh the file handle
* @param size the size of the file
* @return GNUNET_OK if created ok, GNUNET_SYSERR otherwise
*/
static int
make_empty_file (const struct GNUNET_DISK_FileHandle *fh, size_t size)
{
char buffer[BUFFSIZE];
size_t bytesleft = size;
int res = 0;
if (GNUNET_DISK_handle_invalid (fh))
return GNUNET_SYSERR;
memset (buffer, 0, sizeof (buffer));
GNUNET_DISK_file_seek (fh, 0, GNUNET_DISK_SEEK_SET);
while (bytesleft > 0)
{
if (bytesleft > sizeof (buffer))
{
res = GNUNET_DISK_file_write (fh, buffer, sizeof (buffer));
if (res >= 0)
bytesleft -= res;
}
else
{
res = GNUNET_DISK_file_write (fh, buffer, bytesleft);
if (res >= 0)
bytesleft -= res;
}
if (GNUNET_SYSERR == res)
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
/**
* Get the namespace ID belonging to the given namespace name.
*
* @param cfg configuration to use
* @param ns_uname unique (!) human-readable name for the namespace
* @param nsid set to namespace ID based on 'ns_uname'
* @return GNUNET_OK on success, GNUNET_SYSERR on failure
*/
int
GNUNET_PSEUDONYM_name_to_id (const struct GNUNET_CONFIGURATION_Handle *cfg,
const char *ns_uname, struct GNUNET_HashCode * nsid)
{
size_t slen;
uint64_t len;
unsigned int idx;
char *name;
struct GNUNET_HashCode nh;
char *fn;
struct GNUNET_DISK_FileHandle *fh;
idx = -1;
slen = strlen (ns_uname);
while ((slen > 0) && (1 != SSCANF (&ns_uname[slen - 1], "-%u", &idx)))
slen--;
if (slen == 0)
return GNUNET_SYSERR;
name = GNUNET_strdup (ns_uname);
name[slen - 1] = '\0';
GNUNET_CRYPTO_hash (name, strlen (name), &nh);
GNUNET_free (name);
fn = get_data_filename (cfg, PS_NAMES_DIR, &nh);
GNUNET_assert (fn != NULL);
if ((GNUNET_OK != GNUNET_DISK_file_test (fn) ||
(GNUNET_OK != GNUNET_DISK_file_size (fn, &len, GNUNET_YES, GNUNET_YES))) ||
((idx + 1) * sizeof (struct GNUNET_HashCode) > len))
{
GNUNET_free (fn);
return GNUNET_SYSERR;
}
fh = GNUNET_DISK_file_open (fn,
GNUNET_DISK_OPEN_CREATE |
GNUNET_DISK_OPEN_READWRITE,
GNUNET_DISK_PERM_USER_READ |
GNUNET_DISK_PERM_USER_WRITE);
GNUNET_free (fn);
if (GNUNET_SYSERR ==
GNUNET_DISK_file_seek (fh, idx * sizeof (struct GNUNET_HashCode),
GNUNET_DISK_SEEK_SET))
{
GNUNET_DISK_file_close (fh);
return GNUNET_SYSERR;
}
if (sizeof (struct GNUNET_HashCode) !=
GNUNET_DISK_file_read (fh, nsid, sizeof (struct GNUNET_HashCode)))
{
GNUNET_DISK_file_close (fh);
return GNUNET_SYSERR;
}
GNUNET_DISK_file_close (fh);
return GNUNET_OK;
}
/**
* Sets a bit active in the bitArray and increments
* bit-specific usage counter on disk (but only if
* the counter was below 4 bit max (==15)).
*
* @param bitArray memory area to set the bit in
* @param bitIdx which bit to test
* @param fh A file to keep the 4 bit address usage counters in
*/
static void
incrementBit (char *bitArray, unsigned int bitIdx,
const struct GNUNET_DISK_FileHandle *fh)
{
OFF_T fileSlot;
unsigned char value;
unsigned int high;
unsigned int low;
unsigned int targetLoc;
setBit (bitArray, bitIdx);
if (GNUNET_DISK_handle_invalid (fh))
return;
/* Update the counter file on disk */
fileSlot = bitIdx / 2;
targetLoc = bitIdx % 2;
GNUNET_assert (fileSlot ==
GNUNET_DISK_file_seek (fh, fileSlot, GNUNET_DISK_SEEK_SET));
if (1 != GNUNET_DISK_file_read (fh, &value, 1))
value = 0;
low = value & 0xF;
high = (value & (~0xF)) >> 4;
if (targetLoc == 0)
{
if (low < 0xF)
low++;
}
else
{
if (high < 0xF)
high++;
}
value = ((high << 4) | low);
GNUNET_assert (fileSlot ==
GNUNET_DISK_file_seek (fh, fileSlot, GNUNET_DISK_SEEK_SET));
GNUNET_assert (1 == GNUNET_DISK_file_write (fh, &value, 1));
}
/**
* Function called by the tree encoder to obtain
* a block of plaintext data (for the lowest level
* of the tree).
*
* @param cls our publishing context
* @param offset identifies which block to get
* @param max (maximum) number of bytes to get; returning
* fewer will also cause errors
* @param buf where to copy the plaintext buffer
* @param emsg location to store an error message (on error)
* @return number of bytes copied to buf, 0 on error
*/
static size_t
unindex_reader (void *cls,
uint64_t offset,
size_t max,
void *buf,
char **emsg)
{
struct GNUNET_FS_UnindexContext *uc = cls;
size_t pt_size;
pt_size = GNUNET_MIN (max, uc->file_size - offset);
if (offset != GNUNET_DISK_file_seek (uc->fh, offset, GNUNET_DISK_SEEK_SET))
{
*emsg = GNUNET_strdup (_("Failed to find given position in file"));
return 0;
}
if (pt_size != GNUNET_DISK_file_read (uc->fh, buf, pt_size))
{
*emsg = GNUNET_strdup (_("Failed to read file"));
return 0;
}
return pt_size;
}
/**
* We've received an on-demand encoded block from the datastore.
* Attempt to do on-demand encoding and (if successful), call the
* continuation with the resulting block. On error, clean up and ask
* the datastore for more results.
*
* @param key key for the content
* @param size number of bytes in data
* @param data content stored
* @param type type of the content
* @param priority priority of the content
* @param anonymity anonymity-level for the content
* @param expiration expiration time for the content
* @param uid unique identifier for the datum;
* maybe 0 if no unique identifier is available
* @param cont function to call with the actual block (at most once, on success)
* @param cont_cls closure for cont
* @return GNUNET_OK on success
*/
int
GNUNET_FS_handle_on_demand_block (const struct GNUNET_HashCode * key, uint32_t size,
const void *data, enum GNUNET_BLOCK_Type type,
uint32_t priority, uint32_t anonymity,
struct GNUNET_TIME_Absolute expiration,
uint64_t uid,
GNUNET_DATASTORE_DatumProcessor cont,
void *cont_cls)
{
const struct OnDemandBlock *odb;
struct GNUNET_HashCode nkey;
struct GNUNET_CRYPTO_AesSessionKey skey;
struct GNUNET_CRYPTO_AesInitializationVector iv;
struct GNUNET_HashCode query;
ssize_t nsize;
char ndata[DBLOCK_SIZE];
char edata[DBLOCK_SIZE];
const char *fn;
struct GNUNET_DISK_FileHandle *fh;
uint64_t off;
struct IndexInfo *ii;
if (size != sizeof (struct OnDemandBlock))
{
GNUNET_break (0);
GNUNET_DATASTORE_remove (dsh, key, size, data, -1, -1,
GNUNET_TIME_UNIT_FOREVER_REL, &remove_cont, NULL);
return GNUNET_SYSERR;
}
odb = (const struct OnDemandBlock *) data;
off = GNUNET_ntohll (odb->offset);
ii = GNUNET_CONTAINER_multihashmap_get (ifm, &odb->file_id);
if (NULL == ii)
{
GNUNET_break (0);
return GNUNET_SYSERR;
}
fn = ii->filename;
if ((NULL == fn) || (0 != ACCESS (fn, R_OK)))
{
GNUNET_STATISTICS_update (GSF_stats,
gettext_noop
("# index blocks removed: original file inaccessible"),
1, GNUNET_YES);
GNUNET_DATASTORE_remove (dsh, key, size, data, -1, -1,
GNUNET_TIME_UNIT_FOREVER_REL, &remove_cont, NULL);
return GNUNET_SYSERR;
}
if ((NULL ==
(fh =
GNUNET_DISK_file_open (fn, GNUNET_DISK_OPEN_READ,
GNUNET_DISK_PERM_NONE))) ||
(off != GNUNET_DISK_file_seek (fh, off, GNUNET_DISK_SEEK_SET)) ||
(-1 == (nsize = GNUNET_DISK_file_read (fh, ndata, sizeof (ndata)))))
{
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
_
("Could not access indexed file `%s' (%s) at offset %llu: %s\n"),
GNUNET_h2s (&odb->file_id), fn, (unsigned long long) off,
(fn == NULL) ? _("not indexed") : STRERROR (errno));
if (fh != NULL)
GNUNET_DISK_file_close (fh);
GNUNET_DATASTORE_remove (dsh, key, size, data, -1, -1,
GNUNET_TIME_UNIT_FOREVER_REL, &remove_cont, NULL);
return GNUNET_SYSERR;
}
GNUNET_DISK_file_close (fh);
GNUNET_CRYPTO_hash (ndata, nsize, &nkey);
GNUNET_CRYPTO_hash_to_aes_key (&nkey, &skey, &iv);
GNUNET_CRYPTO_aes_encrypt (ndata, nsize, &skey, &iv, edata);
GNUNET_CRYPTO_hash (edata, nsize, &query);
if (0 != memcmp (&query, key, sizeof (struct GNUNET_HashCode)))
{
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
_("Indexed file `%s' changed at offset %llu\n"), fn,
(unsigned long long) off);
GNUNET_DATASTORE_remove (dsh, key, size, data, -1, -1,
GNUNET_TIME_UNIT_FOREVER_REL, &remove_cont, NULL);
return GNUNET_SYSERR;
}
GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
"On-demand encoded block for query `%s'\n", GNUNET_h2s (key));
cont (cont_cls, key, nsize, edata, GNUNET_BLOCK_TYPE_FS_DBLOCK, priority,
anonymity, expiration, uid);
return GNUNET_OK;
}
