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|
/*
This file is part of TALER
Copyright (C) 2014-2020 Taler Systems SA
TALER 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 3, or (at your option) any later version.
TALER is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
TALER; see the file COPYING. If not, see <http://www.gnu.org/licenses/>
*/
/**
* @file util/taler-helper-crypto-rsa.c
* @brief Standalone process to perform private key RSA operations
* @author Christian Grothoff
*
* NOTES:
* - Option 'DURATION_OVERLAP' renamed to 'OVERLAP_DURATION' for consistency;
* => need to update in deployment scripts and default configuration!
* - option 'KEYDIR' moved from section 'exchange' to 'taler-helper-crypto-rsa'!
*
* Key design points:
* - EVERY thread of the exchange will have its own pair of connections to the
* crypto helpers. This way, every threat will also have its own /keys state
* and avoid the need to synchronize on those.
* - auditor signatures and master signatures are to be kept in the exchange DB,
* and merged with the public keys of the helper by the exchange HTTPD!
* - the main loop of the helper is SINGLE-THREADED, but there are
* threads for crypto-workers which (only) do the signing in parallel,
* working of a work-queue.
* - thread-safety: signing happens in parallel, thus when REMOVING private keys,
* we must ensure that all signers are done before we fully free() the
* private key. This is done by reference counting (as work is always
* assigned and collected by the main thread).
*
* TODO:
* - actual networking
* - actual signing
*/
#include "platform.h"
#include "taler_util.h"
#include "taler-helper-crypto-rsa.h"
#include <gcrypt.h>
/**
* Information we keep per denomination.
*/
struct Denomination;
/**
* One particular denomination key.
*/
struct DenominationKey
{
/**
* Kept in a DLL of the respective denomination. Sorted by anchor time.
*/
struct DenominationKey *next;
/**
* Kept in a DLL of the respective denomination. Sorted by anchor time.
*/
struct DenominationKey *prev;
/**
* Denomination this key belongs to.
*/
struct Denomination *denom;
/**
* Name of the file this key is stored under.
*/
char *filename;
/**
* The private key of the denomination. Will be NULL if the private
* key is not available (this is the case after the key has expired
* for signing coins, but is still valid for depositing coins).
*/
struct TALER_DenominationPrivateKey denom_priv;
/**
* The public key of the denomination.
*/
struct TALER_DenominationPublicKey denom_pub;
/**
* Hash of this denomination's public key.
*/
struct GNUNET_HashCode h_pub;
/**
* Time at which this key is supposed to become valid.
*/
struct GNUNET_TIME_Absolute anchor;
/**
* Reference counter. Counts the number of threads that are
* using this key at this time.
*/
unsigned int rc;
/**
* Flag set to true if this key has been purged and the memory
* must be freed as soon as @e rc hits zero.
*/
bool purge;
};
struct Denomination
{
/**
* Kept in a DLL. Sorted by #denomination_action_time().
*/
struct Denomination *next;
/**
* Kept in a DLL. Sorted by #denomination_action_time().
*/
struct Denomination *prev;
/**
* Head of DLL of actual keys of this denomination.
*/
struct DenominationKey *keys_head;
/**
* Tail of DLL of actual keys of this denomination.
*/
struct DenominationKey *keys_tail;
/**
* How long can coins be withdrawn (generated)? Should be small
* enough to limit how many coins will be signed into existence with
* the same key, but large enough to still provide a reasonable
* anonymity set.
*/
struct GNUNET_TIME_Relative duration_withdraw;
/**
* What is the configuration section of this denomination type? Also used
* for the directory name where the denomination keys are stored.
*/
char *section;
/**
* Length of (new) RSA keys (in bits).
*/
uint32_t rsa_keysize;
};
/**
* Information we keep for a client connected to us.
*/
struct Client
{
/**
* Kept in a DLL.
*/
struct Client *next;
/**
* Kept in a DLL.
*/
struct Client *prev;
/**
* Client socket.
*/
struct GNUNET_NETWORK_Handle *sock;
/**
* Client task to read from @e sock. NULL if we are working.
*/
struct GNUNET_SCHEDULER_Task *task;
};
/**
* Return value from main().
*/
static int global_ret;
/**
* Time when the key update is executed.
* Either the actual current time, or a pretended time.
*/
static struct GNUNET_TIME_Absolute now;
/**
* The time for the key update, as passed by the user
* on the command line.
*/
static struct GNUNET_TIME_Absolute now_tmp;
/**
* Handle to the exchange's configuration
*/
static const struct GNUNET_CONFIGURATION_Handle *kcfg;
/**
* Where do we store the keys?
*/
static const char *keydir;
/**
* How much should coin creation (@e duration_withdraw) duration overlap
* with the next denomination? Basically, the starting time of two
* denominations is always @e duration_withdraw - #duration_overlap apart.
*/
static struct GNUNET_TIME_Relative overlap_duration;
/**
* How long into the future do we pre-generate keys?
*/
static struct GNUNET_TIME_Relative lookahead_sign;
/**
* Until what time do we provide keys?
*/
static struct GNUNET_TIME_Absolute lookahead_sign_stamp;
/**
* All of our denominations, in a DLL. Sorted?
*/
static struct Denomination *denom_head;
/**
* All of our denominations, in a DLL. Sorted?
*/
static struct Denomination *denom_tail;
/**
* Map of hashes of public (RSA) keys to `struct DenominationKey *`
* with the respective private keys.
*/
static struct GNUNET_CONTAINER_MultiHashMap *keys;
/**
* Our listen socket.
*/
static struct GNUNET_NETWORK_Handle *lsock;
/**
* Task run to accept new inbound connections.
*/
static struct GNUNET_SCHEDULER_Task *accept_task;
/**
* Task run to generate new keys.
*/
static struct GNUNET_SCHEDULER_Task *keygen_task;
/**
* Head of DLL of clients connected to us.
*/
static struct Client *clients_head;
/**
* Tail of DLL of clients connected to us.
*/
static struct Client *clients_tail;
/**
* Function run to read incoming requests from a client.
*
* @param cls the `struct Client`
*/
static void
read_job (void *cls)
{
struct Client *client = cls;
// FIXME: DO WORK!
// check for:
// - sign requests
// - revocation requests!?
}
/**
* Notify @a client about @a dk becoming available.
*
* @param client the client to notify
* @param dk the key to notify @a client about
* @return #GNUNET_OK on success
*/
static int
notify_client_dk_add (const struct Client *client,
const struct DenominationKey *dk)
{
// FIXME: send msg!
return GNUNET_SYSERR;
}
/**
* Notify @a client about @a dk being purged.
*
* @param client the client to notify
* @param dk the key to notify @a client about
* @return #GNUNET_OK on success
*/
static int
notify_client_dk_del (const struct Client *client,
const struct DenominationKey *dk)
{
struct TALER_CRYPTO_RsaKeyPurgeNotification pn = {
.header.type = htons (TALER_HELPER_RSA_MT_PURGE),
.header.size = htons (sizeof (pn)),
.h_denom_pub = dk->h_pub
};
ssize_t ret;
ret = send (GNUNET_NETWORK_get_fd (client->sock),
&pn,
sizeof (pn),
0);
if (sizeof (pn) != ret)
{
GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING,
"send");
GNUNET_NETWORK_socket_close (client->sock);
GNUNET_CONTAINER_DLL_remove (client_head,
client_tail,
client);
GNUNET_free (client);
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
/**
* Function run to accept incoming connections on #sock.
*
* @param cls NULL
*/
static void
accept_job (void *cls)
{
struct GNUNET_NETWORK_Handle *sock;
struct sockaddr_storage addr;
socklen_t alen;
accept_task = NULL;
alen = sizeof (addr);
sock = GNUNET_NETWORK_socket_accept (lsock,
(struct sockaddr *) &addr,
&alen);
if (NULL != sock)
{
struct Client *client;
client = GNUNET_new (struct Client);
client->sock = sock;
GNUNET_CONTAINER_DLL_insert (clients_head,
clients_tail,
client);
client->task = GNUNET_SCHEDULER_add_read (GNUNET_TIME_UNIT_FOREVER_REL,
sock,
&read_job,
client);
for (struct Denomination *denom = denom_head;
NULL != denom;
denom = denom->next)
{
for (struct DenominationKey *dk = denom->keys_head;
NULL != dk;
dk = dk->next)
{
if (GNUNET_OK !=
notify_client_dk_add (client,
dk))
{
/* client died, skip the rest */
client = NULL;
break;
}
}
if (NULL == client)
break;
}
}
accept_task = GNUNET_SCHEDULER_add_read (GNUNET_TIME_UNIT_FOREVER_REL,
lsock,
&accept_job,
NULL);
}
/**
* Create a new denomination key (we do not have enough).
*
* @param denom denomination key to create
* @return #GNUNET_OK on success
*/
static int
create_key (struct Denomination *denom)
{
struct DenominationKey *dk;
struct GNUNET_TIME_Absolute anchor;
struct GNUNET_CRYPTO_RsaPrivateKey *priv;
struct GNUNET_CRYPTO_RsaPublicKey *pub;
size_t buf_size;
void *buf;
if (NULL == denom->keys_tail)
{
anchor = GNUNET_TIME_absolute_get ();
(void) GNUNET_TIME_absolute_round (&anchor);
}
else
{
anchor = GNUNET_TIME_absolute_add (denom->keys_tail.anchor,
GNUNET_TIME_relative_subtract (
denom->duration_withdraw,
overlap_duration));
}
priv = GNUNET_CRYPTO_rsa_private_key_create (denom->rsa_keysize);
if (NULL == priv)
{
GNUNET_break (0);
GNUNET_SCHEDULER_shutdown ();
global_ret = 40;
return GNUNET_SYSERR;
}
pub = GNUNET_CRYPTO_rsa_private_key_get_public (priv);
if (NULL == pub)
{
GNUNET_break (0);
GNUNET_CRYPTO_rsa_private_key_free (priv);
GNUNET_SCHEDULER_shutdown ();
global_ret = 41;
return;
}
buf_size = GNUNET_CRYPTO_rsa_private_key_encode (priv,
&buf);
dk = GNUNET_new (struct DenominationKey);
dk->denom = denom;
dk->anchor = anchor;
dk->denom_priv.rsa_priv = priv;
GNUNET_CRYPTO_rsa_public_key_hash (pub,
&dk->h_pub);
dk->denom_pub.rsa_pub = pub;
GNUNET_asprintf (&dk->filename,
"%s/%s/%llu",
keydir,
denom->section,
anchor.abs_value_us / GNUNET_TIME_UNIT_SECONDS.rel_value_us);
if (buf_size !=
GNUNET_DISK_fn_write (dk->filename,
buf,
buf_size,
GNUNET_DISK_PERM_USER_READ))
{
GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
"write",
dk->filename);
GNUNET_free (buf);
GNUNET_CRYPTO_rsa_private_key_free (priv);
GNUNET_CRYPTO_rsa_public_key_free (pub);
GNUNET_free (dk);
GNUNET_SCHEDULER_shutdown ();
global_ret = 42;
return GNUNET_SYSERR;
}
GNUNET_free (buf);
if (GNUNET_OK !=
GNUNET_CONTAINER_multihashmap_put (
keys,
&dk->h_pub,
dk,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Duplicate private key created! Terminating.\n");
GNUNET_CRYPTO_rsa_private_key_free (priv);
GNUNET_CRYPTO_rsa_public_key_free (pub);
GNUNET_free (dk);
GNUNET_SCHEDULER_shutdown ();
global_ret = 43;
return;
}
GNUNET_CONTAINER_DLL_insert_tail (denom_keys_head,
denom_keys_tail,
dk);
{
struct Client *nxt;
for (struct Client *client = clients_head;
NULL != client;
client = nxt)
{
nxt = client->next;
if (GNUNET_OK !=
notify_client_dk_add (client,
dk))
{
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Failed to notify client about new key, client dropped\n");
}
}
}
}
/**
* At what time does this denomination require its next action?
* Basically, the minimum of the withdraw expiration time of the
* oldest denomination key, and the withdraw expiration time of
* the newest denomination key minus the #lookahead_sign time.
*
* @param denon denomination to compute action time for
*/
static struct GNUNET_TIME_Absolute
denomination_action_time (const struct Denomination *denom)
{
return GNUNET_TIME_absolute_min (
GNUNET_TIME_absolute_add (denom->keys_head->anchor,
denom->duration_withdraw),
GNUNET_TIME_absolute_subtract (
GNUNET_TIME_absolute_subtract (
GNUNET_TIME_absolute_add (denom->keys_tail->anchor,
denom->duration_withdraw),
lookahead_sign),
overlap_duration));
}
/**
* The withdraw period of a key @a dk has expired. Purge it.
*
* @param[in] dk expired denomination key to purge and free
*/
static void
purge_key (struct DenominationKey *dk)
{
struct Denomination *denom = dk->denom;
struct Client *nxt;
for (struct Client *client = clients_head;
NULL != client;
client = nxt)
{
nxt = client->next;
if (GNUNET_OK !=
notify_client_dk_del (client,
dk))
{
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Failed to notify client about purged key, client dropped\n");
}
}
GNUNET_CONTAINER_DLL_remove (denom->keys_head,
denom->keys_tail,
dk);
GNUNET_assert (GNUNET_OK ==
GNUNET_CONTAINER_multihashmap_remove (keys,
&dk->h_pub,
dk));
if (0 != unlink (dk->filename))
{
GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
"unlink",
dk->filename);
}
else
{
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Purged expired private key `%s'\n",
dk->filename);
}
GNUNET_free (dk->filename);
if (0 != dk->rc)
{
/* delay until all signing threads are done with this key */
dk->purge = true;
return;
}
GNUNET_CRYPTO_rsa_private_key_free (dk->denom_priv.rsa_priv);
GNUNET_free (dk);
}
/**
* Create new keys and expire ancient keys of the given denomination @a denom.
* Removes the @a denom from the #denom_head DLL and re-insert its at the
* correct location sorted by next maintenance activity.
*
* @param[in,out] denom denomination to update material for
*/
static void
update_keys (struct Denomination *denom)
{
/* create new denomination keys */
while ( (NULL == denom->denom_tail) ||
(0 ==
GNUNET_TIME_absolute_get_remaining
GNUNET_TIME_absolute_subtract (
GNUNET_TIME_absolute_subtract (
GNUNET_TIME_absolute_add (denom->keys_tail->anchor,
denom->duration_withdraw),
lookahead_sign),
overlap_duration)) )
if (GNUNET_OK !=
create_key (denom))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Failed to create keys for `%s'\n",
denom->section);
return;
}
/* remove expired denomination keys */
while ( (NULL != denom->denom_head) &&
(0 ==
GNUNET_TIME_absolute_get_remaining
(GNUNET_TIME_absolute_add (denom->denom_head.anchor,
denom->duration_withdraw))) )
purge_key (denom->denom_head);
/* Update position of 'denom' in #denom_head DLL: sort by action time */
{
struct Denomination *before;
struct GNUNET_TIME_Absolute at;
at = denomination_action_time (denom);
before = NULL;
GNUNET_CONTAINER_DLL_remove (denom_head,
denom_tail,
denom);
for (struct Denomination *pos = denom_head;
NULL != pos;
pos = pos->next)
{
if (denomination_action_time (pos).abs_value_us > at.abs_value_us)
break;
before = pos;
}
GNUNET_CONTAINER_DLL_insert_after (denom_head,
denom_tail,
before,
denom);
}
}
/**
* Task run periodically to expire keys and/or generate fresh ones.
*
* @param cls NULL
*/
static void
update_denominations (void *cls)
{
struct Denomination *denom;
(void) cls;
keygen_task = NULL;
do {
denom = denom_head;
update_keys (denom);
} while (denom != denom_head);
keygen_task = GNUNET_SCHEDULER_add_at (TIME,
&update_denominations,
denomination_action_time (denom));
}
/**
* Parse private key of denomination @a denom in @a buf.
*
* @param[out] denom denomination of the key
* @param filename name of the file we are parsing, for logging
* @param buf key material
* @param buf_size number of bytes in @a buf
*/
static void
parse_key (struct Denomination *denom,
const char *filename,
const void *buf,
size_t buf_size)
{
struct GNUNET_CRYPTO_RsaPrivateKey *priv;
char *anchor_s;
char dummy;
unsigned long long anchor_ll;
struct GNUNET_TIME_Absolute anchor;
anchor_s = strrchr (filename,
'/');
if (NULL == anchor_s)
{
/* File in a directory without '/' in the name, this makes no sense. */
GNUNET_break (0);
return;
}
anchor_s++;
if (1 != sscanf (anchor_s,
"%llu%c",
&anchor_ll,
&dummy))
{
/* Filenames in KEYDIR must ONLY be the anchor time in seconds! */
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
"Filename `%s' invalid for key file, skipping\n",
filename);
return;
}
anchor.abs_time_us = anchor_ll * GNUNET_TIME_UNIT_SECONDS.rel_value_us;
if (anchor_ll != anchor.abs_time_us / GNUNET_TIME_UNIT_SECONDS.rel_value_us)
{
/* Integer overflow. Bad, invalid filename. */
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
"Filename `%s' invalid for key file, skipping\n",
filename);
return;
}
priv = GNUNET_CRYPTO_rsa_private_key_decode (buf,
buf_size);
if (NULL == priv)
{
/* Parser failure. */
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
"File `%s' is malformed, skipping\n",
filename);
return;
}
{
struct GNUNET_CRYPTO_RsaPublicKey *pub;
struct DenominationKey *dk;
struct DenominationKey *before;
pub = GNUNET_CRYPTO_rsa_private_key_get_public (priv);
if (NULL == pub)
{
GNUNET_break (0);
GNUNET_CRYPTO_rsa_private_key_free (priv);
return;
}
dk = GNUNET_new (struct DenominationKey);
dk->denom_priv.rsa_priv = priv;
dk->denomination = denom;
dk->anchor = anchor;
dk->filename = GNUNET_strdup (filename);
GNUNET_CRYPTO_rsa_public_key_hash (pub,
&dk->h_pub);
dk->denom_pub.rsa_pub = pub;
if (GNUNET_OK !=
GNUNET_CONTAINER_multihashmap_put (
keys,
&dk->h_pub,
dk,
GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Duplicate private key detected in file `%s'. Skipping.\n",
filename);
GNUNET_CRYPTO_rsa_private_key_free (priv);
GNUNET_CRYPTO_rsa_public_key_free (pub);
GNUNET_free (dk);
return;
}
before = NULL;
for (struct DenominationKey *pos = denom->keys_head;
NULL != pos;
pos = pos->next)
{
if (pos->anchor.abs_value_us > anchor.abs_value_us)
break;
before = pos;
}
GNUNET_CONTAINER_DLL_insert_after (denom->keys_head,
denom->keys_tail,
before,
dk);
}
}
/**
* Import a private key from @a filename for the denomination
* given in @a cls.
*
* @param[in,out] cls a `struct Denomiantion`
* @param filename name of a file in the directory
*/
static int
import_key (void *cls,
const char *filename)
{
struct Denomination *denom = cls;
struct GNUNET_DISK_FileHandle *fh;
struct GNUNET_DISK_MapHandle *map;
off_t fsize;
void *ptr;
int fd;
struct stat sbuf;
{
struct stat lsbuf;
if (0 != lstat (filename,
&lsbuf))
{
GNUNET_log_strerror_filename (GNUNET_ERROR_TYPE_WARNING,
"lstat",
filename);
return GNUNET_OK;
}
if (! S_ISREG (lsbuf.st_mode))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"File `%s' is not a regular file, which is not allowed for private keys!\n",
filename);
return GNUNET_OK;
}
}
fd = open (filename,
O_CLOEXEC);
if (-1 == fd)
{
GNUNET_log_strerror_filename (GNUNET_ERROR_TYPE_WARNING,
"open",
filename);
return GNUNET_OK;
}
if (0 != fstat (fd,
&sbuf))
{
GNUNET_log_strerror_filename (GNUNET_ERROR_TYPE_WARNING,
"stat",
filename);
return GNUNET_OK;
}
if (! S_ISREG (sbuf.st_mode))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"File `%s' is not a regular file, which is not allowed for private keys!\n",
filename);
return GNUNET_OK;
}
if (0 != (sbuf.st_mode & (S_IWUSR | S_IRWXG | S_IRWXO)))
{
/* permission are NOT tight, try to patch them up! */
if (0 !=
fchmod (fd,
S_IRUSR))
{
GNUNET_log_strerror_filename (GNUNET_ERROR_TYPE_WARNING,
"fchmod",
filename);
/* refuse to use key if file has wrong permissions */
GNUNET_break (0 == close (fd));
return GNUNET_OK;
}
}
fh = GNUNET_DISK_get_handle_from_int_fd (fd);
if (NULL == fh)
{
GNUNET_log_strerror_filename (GNUNET_ERROR_TYPE_WARNING,
"open",
filename);
GNUNET_break (0 == close (fd));
return GNUNET_OK;
}
if (sbuf.st_size > 2048)
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"File `%s' to big to be a private key\n",
filename);
GNUNET_DISK_file_close (fh);
return GNUNET_OK;
}
ptr = GNUNET_DISK_file_map (fh,
&map,
GNUNET_DISK_MAP_TYPE_READ,
(size_t) sbuf.st_size);
if (NULL == ptr)
{
GNUNET_log_strerror_filename (GNUNET_ERROR_TYPE_WARNING,
"mmap",
filename);
GNUNET_DISK_file_close (fh);
return GNUNET_OK;
}
parse_key (denom,
filename,
ptr,
(size_t) sbuf.st_size);
GNUNET_DISK_file_unmap (map);
GNUNET_DISK_file_close (fh);
return GNUNET_OK;
}
/**
* Generate new denomination signing keys for the denomination type of the given @a
* denomination_alias.
*
* @param cls a `int *`, to be set to #GNUNET_SYSERR on failure
* @param denomination_alias name of the denomination's section in the configuration
*/
static void
load_denominations (void *cls,
const char *denomination_alias)
{
int *ret = cls;
struct Denomination *denom;
if (0 != strncasecmp (denomination_alias,
"coin_",
strlen ("coin_")))
return; /* not a denomination type definition */
denom = GNUNET_new (struct Denomination);
if (GNUNET_OK !=
parse_denomination_cfg (denomination_alias,
denom))
{
*ret = GNUNET_SYSERR;
GNUNET_free (denom);
return;
}
{
char *dname;
GNUNET_asprintf (&dname,
"%s/%s",
keydir,
denom->section);
GNUNET_DISK_directory_scan (dname,
&import_key,
denom);
GNUNET_free (dname);
}
GNUNET_CONTAINER_DLL_insert (denom_head,
denom_tail,
denom);
update_keys (denom);
}
/**
* Load the various duration values from #kcfg.
*
* @return #GNUNET_OK on success
*/
static int
load_durations (void)
{
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_time (kcfg,
"exchangedb",
"OVERLAP_DURATION",
&overlap_duration))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
"exchangedb",
"OVERLAP_DURATION");
return GNUNET_SYSERR;
}
GNUNET_TIME_round_rel (&overlap_duration);
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_time (kcfg,
"exchange",
"LOOKAHEAD_SIGN",
&lookahead_sign))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
"exchange",
"LOOKAHEAD_SIGN");
return GNUNET_SYSERR;
}
GNUNET_TIME_round_rel (&lookahead_sign);
return GNUNET_OK;
}
/**
* Parse configuration for denomination type parameters. Also determines
* our anchor by looking at the existing denominations of the same type.
*
* @param ct section in the configuration file giving the denomination type parameters
* @param[out] denom set to the denomination parameters from the configuration
* @return #GNUNET_OK on success, #GNUNET_SYSERR if the configuration is invalid
*/
static int
parse_denomination_cfg (const char *ct,
struct Denomination *denom)
{
const char *dir;
unsigned long long rsa_keysize;
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_time (kcfg,
ct,
"DURATION_WITHDRAW",
&denom->duration_withdraw))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
ct,
"DURATION_WITHDRAW");
return GNUNET_SYSERR;
}
GNUNET_TIME_round_rel (&denom->duration_withdraw);
if (duration_overlap.rel_value_us >=
denom->duration_withdraw.rel_value_us)
{
GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
"exchangedb",
"DURATION_OVERLAP",
"Value given for DURATION_OVERLAP must be smaller than value for DURATION_WITHDRAW!");
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_number (kcfg,
ct,
"RSA_KEYSIZE",
&rsa_keysize))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
ct,
"RSA_KEYSIZE");
return GNUNET_SYSERR;
}
if ( (rsa_keysize > 4 * 2048) ||
(rsa_keysize < 1024) )
{
GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
"exchangedb",
"RSA_KEYSIZE",
"Given RSA keysize outside of permitted range [1024,8192]\n");
return GNUNET_SYSERR;
}
denom->rsa_keysize = (unsigned int) rsa_keysize;
denom->section = GNUNET_strdup (ct);
return GNUNET_OK;
}
/**
* Function run on shutdown. Stops the various jobs (nicely).
*
* @param cls NULL
*/
static void
do_shutdown (void *cls)
{
(void) cls;
if (NULL != accept_task)
{
GNUNET_SCHEDULER_cancel (accept_task);
accept_task = NULL;
}
if (NULL != lsock)
{
GNUNET_break (0 ==
GNUNET_NETWORK_socket_close (lsock));
lsock = NULL;
}
if (NULL != keygen_task)
{
GNUNET_SCHEDULER_cancel (keygen_task);
keygen_task = NULL;
}
}
/**
* Main function that will be run under the GNUnet scheduler.
*
* @param cls closure
* @param args remaining command-line arguments
* @param cfgfile name of the configuration file used (for saving, can be NULL!)
* @param cfg configuration
*/
static void
run (void *cls,
char *const *args,
const char *cfgfile,
const struct GNUNET_CONFIGURATION_Handle *cfg)
{
(void) cls;
(void) args;
(void) cfgfile;
kcfg = cfg;
if (now.abs_value_us != now_tmp.abs_value_us)
{
/* The user gave "--now", use it! */
now = now_tmp;
}
else
{
/* get current time again, we may be timetraveling! */
now = GNUNET_TIME_absolute_get ();
}
GNUNET_TIME_round_abs (&now);
if (GNUNET_OK !=
load_durations ())
{
global_ret = 1;
return;
}
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_filename (kcfg,
"taler-helper-crypto-rsa",
"KEYDIR",
&keydir))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
"exchange",
"KEYDIR");
global_ret = 1;
return;
}
/* open socket */
{
int sock;
sock = socket (PF_UNIX,
SOCK_DGRAM,
0);
if (-1 == sock)
{
GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
"socket");
global_ret = 2;
return;
}
{
struct sockaddr_un un;
char *unixpath;
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_filename (kcfg,
"exchange-helper-crypto-rsa",
"UNIXPATH",
&unixpath))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
"exchange-helper-crypto-rsa",
"UNIXPATH");
global_ret = 3;
return;
}
memset (&un,
0,
sizeof (un));
un.sun_family = AF_UNIX;
strncpy (un.sun_path,
unixpath,
sizeof (un.sun_path));
if (0 != bind (sock,
(const struct sockaddr *) &un,
sizeof (un)))
{
GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
"bind",
unixpath);
global_ret = 3;
GNUNET_break (0 == close (sock));
return;
}
}
lsock = GNUNET_NETWORK_socket_box_native (sock);
}
GNUNET_SCHEDULER_add_shutdown (&do_shutdown,
NULL);
/* Load denominations */
keys = GNUNET_CONTAINER_multihashmap_create (65536,
GNUNET_YES);
{
int ok;
ok = GNUNET_OK;
GNUNET_CONFIGURATION_iterate_sections (kcfg,
&load_denominations,
&ok);
if (GNUNET_OK != ok)
{
global_ret = 4;
GNUNET_SCHEDULER_shutdown ();
return;
}
}
if (NULL == denom_head)
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"No denominations configured\n");
global_ret = 5;
GNUNET_SCHEDULER_shutdown ();
return;
}
/* start job to accept incoming requests on 'sock' */
accept_task = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
lsock,
&accept_job,
NULL);
/* start job to keep keys up-to-date */
keygen_task = GNUNET_SCHEDULER_add_now (&update_denominations,
NULL);
}
/**
* The entry point.
*
* @param argc number of arguments in @a argv
* @param argv command-line arguments
* @return 0 on normal termination
*/
int
main (int argc,
char **argv)
{
struct GNUNET_GETOPT_CommandLineOption options[] = {
GNUNET_GETOPT_option_timetravel ('T',
"timetravel"),
GNUNET_GETOPT_option_absolute_time ('t',
"time",
"TIMESTAMP",
"pretend it is a different time for the update",
&now_tmp),
GNUNET_GETOPT_OPTION_END
};
int ret;
umask (S_IWGRP | S_IROTH | S_IWOTH | S_IXOTH);
/* force linker to link against libtalerutil; if we do
not do this, the linker may "optimize" libtalerutil
away and skip #TALER_OS_init(), which we do need */
(void) TALER_project_data_default ();
GNUNET_assert (GNUNET_OK ==
GNUNET_log_setup ("taler-helper-crypto-rsa",
"WARNING",
NULL));
now = now_tmp = GNUNET_TIME_absolute_get ();
ret = GNUNET_PROGRAM_run (argc, argv,
"taler-helper-crypto-rsa",
"Handle private RSA key operations for a Taler exchange",
options,
&run,
NULL);
if (GNUNET_NO == ret)
return 0;
if (GNUNET_SYSERR == ret)
return 1;
return global_ret;
}
|