/*
* This file is part of the Distributed Network Block Device 3
*
* Copyright(c) 2011-2012 Johann Latocha <johann@latocha.de>
*
* This file may be licensed under the terms of of the
* GNU General Public License Version 2 (the ``GPL'').
*
* Software distributed under the License is distributed
* on an ``AS IS'' basis, WITHOUT WARRANTY OF ANY KIND, either
* express or implied. See the GPL for the specific language
* governing rights and limitations.
*
* You should have received a copy of the GPL along with this
* program. If not, go to http://www.gnu.org/licenses/gpl.html
* or write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#include <stdlib.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <pthread.h>
#include <string.h>
#include <glib.h>
#include <math.h>
#include <netinet/in.h>
#include "server.h"
#include "saveload.h"
#include "memlog.h"
#include "helper.h"
// Keep parsed config file in memory so it doesn't need to be parsed again every time it's modified
static GKeyFile *_config_handle = NULL;
static dnbd3_image_t *prepare_image(char *image_name, int rid, char *image_file, char *cache_file);
void dnbd3_load_config()
{
gint i, j;
if (_config_handle != NULL)
{
printf("dnbd3_load_config() called more than once\n\n");
exit(EXIT_FAILURE);
}
_config_handle = g_key_file_new();
if (!g_key_file_load_from_file(_config_handle, _config_file_name, G_KEY_FILE_NONE, NULL))
{
printf("ERROR: Config file not found: %s\n", _config_file_name);
exit(EXIT_FAILURE);
}
srand(time(NULL));
_rpc_password = g_key_file_get_string(_config_handle, "settings", "password", NULL);
_cache_dir = g_key_file_get_string(_config_handle, "settings", "cache_dir", NULL);
if (_cache_dir == NULL)
memlogf("[WARNING] No cache dir set! Automatic replication will not work.");
else if (access(_cache_dir, R_OK | W_OK) != 0)
memlogf("[WARNING] Cache dir '%s' is not readable or writable", _cache_dir);
gchar **groups = NULL;
gsize section_count;
groups = g_key_file_get_groups(_config_handle, §ion_count);
for (i = 0; i < section_count; i++)
{
// Ignore settings section
if (strcmp(groups[i], "settings") == 0)
continue;
// List of trusted servers/namespaces
if (strncmp(groups[i], "trust:", 6) == 0)
{
gchar *addr = g_key_file_get_string(_config_handle, groups[i], "address", NULL);
if (addr == NULL)
continue;
dnbd3_trusted_server_t *server = dnbd3_get_trusted_server(addr, TRUE, groups[i]+6);
g_free(addr);
if (server == NULL)
continue;
gsize key_count;
gchar **keys = g_key_file_get_keys(_config_handle, groups[i], &key_count, NULL);
for (j = 0; j < key_count; ++j)
{
if (strcmp(keys[j], "address") == 0)
continue;
char *flags = g_key_file_get_string(_config_handle, groups[i], keys[j], NULL);
g_key_file_remove_key(_config_handle, groups[i], keys[j], NULL);
dnbd3_add_trusted_namespace(server, keys[j], flags);
g_free(flags);
}
g_strfreev(keys);
continue;
}
// An actual image definition
int rid = g_key_file_get_integer(_config_handle, groups[i], "rid", NULL);
if (rid <= 0)
{
memlogf("[ERROR] Invalid rid '%d' for image '%s'", rid, groups[i]);
continue;
}
const time_t delsoft = g_key_file_get_int64(_config_handle, groups[i], "delete_soft", NULL);
const time_t delhard = g_key_file_get_int64(_config_handle, groups[i], "delete_hard", NULL);
if ((delsoft != 0 && delsoft < time(NULL)) || (delhard != 0 && delhard < time(NULL)))
{
memlogf("[INFO] Ignoring image '%s' as its deletion is due", groups[i]);
continue;
}
char *image_file = g_key_file_get_string(_config_handle, groups[i], "file", NULL);
char *cache_file = g_key_file_get_string(_config_handle, groups[i], "cache", NULL);
dnbd3_image_t *image = prepare_image(groups[i], rid, image_file, cache_file);
if (image)
{
_dnbd3_images = g_slist_prepend(_dnbd3_images, image);
}
g_free(image_file);
g_free(cache_file);
}
g_strfreev(groups);
}
int dnbd3_add_image(dnbd3_image_t *image)
{
if (image->file)
{
if (strncmp(image->file, "/dev/dnbd", 9) == 0)
return ERROR_IMAGE_NOT_FOUND;
int fh = open(image->file, O_RDONLY);
if (fh < 0)
return ERROR_IMAGE_NOT_FOUND;
close(fh);
}
// Lock here to prevent concurrent add calls to mess rids up. Cannot happen currently
// as RPC clients are not threaded and they're the only place where this is called,
// but better be safe for the future...
pthread_spin_lock(&_spinlock);
if (image->rid == 0)
{
const dnbd3_image_t *latest = dnbd3_get_image(image->config_group, 0, 0);
if (latest)
image->rid = latest->rid + 1;
else
image->rid = 1;
}
dnbd3_image_t *newimage = prepare_image(image->config_group, image->rid, image->file, image->cache_file);
if (newimage)
{
if (image->file == NULL && newimage->filesize == 0)
newimage->filesize = image->filesize;
_dnbd3_images = g_slist_prepend(_dnbd3_images, newimage);
}
else
{
pthread_spin_unlock(&_spinlock);
return ERROR_SEE_LOG;
}
image = NULL;
// Adding image was successful, write config file
g_key_file_set_integer(_config_handle, newimage->config_group, "rid", newimage->rid);
if (newimage->file)
g_key_file_set_string(_config_handle, newimage->config_group, "file", newimage->file);
if (newimage->cache_file)
g_key_file_set_string(_config_handle, newimage->config_group, "cache", newimage->cache_file);
pthread_spin_unlock(&_spinlock);
const int ret = dnbd3_save_config();
if (ret == ERROR_OK)
memlogf("[INFO] Added new image '%s' (rid %d)", newimage->config_group, newimage->rid);
else
memlogf("[INFO] Added new image '%s' (rid %d), but config file could not be written (%s)", newimage->config_group, newimage->rid, _config_file_name);
return ret;
}
int dnbd3_del_image(dnbd3_image_t *image)
{
if (image->rid <= 0) // Require a specific rid on deletion
return ERROR_RID;
pthread_spin_lock(&_spinlock);
dnbd3_image_t *existing_image = dnbd3_get_image(image->config_group, image->rid, 0);
if(existing_image == NULL)
{
pthread_spin_unlock(&_spinlock);
return ERROR_IMAGE_NOT_FOUND;
}
existing_image->delete_soft = image->delete_soft;
existing_image->delete_hard = image->delete_hard;
g_key_file_set_int64(_config_handle, image->config_group, "delete_soft", existing_image->delete_soft);
g_key_file_set_int64(_config_handle, image->config_group, "delete_hard", existing_image->delete_hard);
pthread_spin_unlock(&_spinlock);
dnbd3_exec_delete(FALSE);
existing_image = NULL;
const int ret = dnbd3_save_config();
if (ret == ERROR_OK)
memlogf("[INFO] Marked for deletion: '%s' (rid %d)", image->config_group, image->rid);
else
memlogf("[WARNING] Marked for deletion: '%s' (rid %d), but config file could not be written (%s)", image->config_group, image->rid, _config_file_name);
return ret;
}
int dnbd3_save_config()
{
pthread_spin_lock(&_spinlock);
char *data = (char *)g_key_file_to_data(_config_handle, NULL, NULL);
if (data == NULL)
{
pthread_spin_unlock(&_spinlock);
memlogf("[ERROR] g_key_file_to_data() failed");
return ERROR_UNSPECIFIED_ERROR;
}
FILE *f = fopen(_config_file_name, "w");
if (f < 0)
{
pthread_spin_unlock(&_spinlock);
g_free(data);
return ERROR_CONFIG_FILE_PERMISSIONS;
}
fputs("# Do not edit this file while dnbd3-server is running\n", f);
fputs(data, f);
fclose(f);
pthread_spin_unlock(&_spinlock);
g_free(data);
return 0;
}
dnbd3_image_t *dnbd3_get_image(char *name_orig, int rid, const char do_lock)
{
dnbd3_image_t *result = NULL, *image;
GSList *iterator;
// For comparison, make sure the name is global and lowercased
char name[strlen(name_orig) + 1];
strcpy(name, name_orig);
strtolower(name);
// Now find the image
if (do_lock)
pthread_spin_lock(&_spinlock);
for (iterator = _dnbd3_images; iterator; iterator = iterator->next)
{
image = iterator->data;
if (rid != 0) // rid was specified
{
if (image->rid == rid && strcmp(name, image->low_name) == 0)
{
result = image;
break;
}
}
else // search max. rid available
{
if (strcmp(name, image->low_name) == 0 && (result == NULL || result->rid < image->rid))
{
result = image;
}
}
}
if (do_lock)
pthread_spin_unlock(&_spinlock);
return result;
}
void dnbd3_handle_sigpipe(int signum)
{
memlogf("ERROR: SIGPIPE received (%s)", strsignal(signum));
}
void dnbd3_handle_sigterm(int signum)
{
memlogf("INFO: SIGTERM or SIGINT received (%s)", strsignal(signum));
dnbd3_cleanup();
}
/**
* Prepare image to be added to image list. Returns a pointer to a newly allocated image struct
* on success, NULL otherwise.
* Note: This function calls dnbd3_get_image without locking, so make sure you lock
* before calling this function while the server is active.
*/
static dnbd3_image_t *prepare_image(char *image_name, int rid, char *image_file, char *cache_file)
{
int j;
if (image_name == NULL)
{
memlogf("[ERROR] Null Image-Name");
return NULL;
}
char *slash = strrchr(image_name, '/');
if (slash == NULL)
{
memlogf("[ERROR] Invalid image name: '%s'", image_name);
return NULL;
}
else
{
*slash = '\0';
if (!is_valid_imagename(slash+1))
{
memlogf("[ERROR] Invalid image name: '%s'", slash+1);
return NULL;
}
if (!is_valid_namespace(image_name))
{
memlogf("[ERROR] Invalid namespace: '%s'", image_name);
*slash = '/';
return NULL;
}
*slash = '/';
}
// Allocate image struct and zero it out by using g_new0
dnbd3_image_t *image = g_new0(dnbd3_image_t, 1);
if (image == NULL)
{
memlogf("[ERROR] Could not allocate dnbd3_image_t while reading config");
return NULL;
}
image->low_name = strdup(image_name);
strtolower(image->low_name);
memlogf("[INFO] Loading image '%s'", image->low_name);
if (dnbd3_get_image(image->low_name, rid, 0))
{
memlogf("[ERROR] Duplicate image in config: '%s' rid:%d", image_name, rid);
goto error;
}
image->config_group = strdup(image_name);
image->rid = rid;
image->relayed = (image_file == NULL || image_file == '\0');
if (image_file && strncmp(image_file, "/dev/dnbd", 9) == 0)
{
printf("[BUG BUG BUG] Image file is %s\n", image_file);
image->relayed = TRUE;
}
if (image->relayed) // Image is relayed (this server acts as proxy)
{
if (strchr(image_name, '/') == NULL)
{
memlogf("[ERROR] Relayed image without global name in config: '%s'", image_name);
goto error;
}
if (cache_file && *cache_file)
image->cache_file = strdup(cache_file);
}
else // Image is a local one, open file to get size
{
image->file = strdup(image_file);
int fd = open(image->file, O_RDONLY);
if (fd < 0)
{
memlogf("[ERROR] Image file not found: '%s'", image->file);
goto error;
}
const off_t size = lseek(fd, 0, SEEK_END);
if (size <= 0)
{
memlogf("[ERROR] File '%s' of image '%s' has size '%lld'. Image ignored.",
image->file, image_name, (long long)size);
goto error;
}
image->filesize = (uint64_t)size;
if (image->filesize & 4095)
{
memlogf("[WARNING] Size of image '%s' is not a multiple of 4096. Last incomplete block will be ignored!",
image->file);
image->filesize &= ~(uint64_t)4095;
}
close(fd);
image->working = 1;
}
if (image->cache_file)
{
// Determine size of cached image
int fd = open(image->cache_file, O_RDONLY);
if (fd >= 0)
{
const off_t size = lseek(fd, 0, SEEK_END);
if (size > 0)
image->filesize = (uint64_t)size;
close(fd);
}
if (image->filesize & 4095)
{
// Cache files should always be truncated to 4kib boundaries already
memlogf("[WARNING] Size of cache file '%s' is not a multiple of 4096. Something's fishy!", image->cache_file);
image->filesize = 0;
}
else if (image->filesize > 0)
{
printf("[DEBUG] Size known %llu for %s\n", (unsigned long long)image->filesize, image->cache_file);
const size_t map_len_bytes = IMGSIZE_TO_MAPBYTES(image->filesize);
image->cache_map = calloc(map_len_bytes, sizeof(uint8_t));
// read cache map from file
char tmp[strlen(image->cache_file) + 5];
strcpy(tmp, image->cache_file);
strcat(tmp, ".map");
fd = open(tmp, O_RDONLY);
if (fd >= 0)
{
const off_t size = lseek(fd, 0, SEEK_END);
if (size != map_len_bytes)
{
memlogf("[DEBUG] Cache-Map of %s is corrupted (%d != %d)", image_name, (int)size, (int)map_len_bytes);
}
else
{
lseek(fd, 0, SEEK_SET);
read(fd, image->cache_map, map_len_bytes);
// If the whole image is cached, mark it as working right away without waiting for an upstream server
image->working = 1;
for (j = 0; j < map_len_bytes - 1; ++j)
{
if (image->cache_map[j] != 0xFF)
{
image->working = 0;
break;
}
}
const int blocks_in_last_byte = (image->filesize >> 12) & 7;
uint8_t last_byte = 0;
if (blocks_in_last_byte == 0)
last_byte = 0xFF;
else
for (j = 0; j < blocks_in_last_byte; ++j)
last_byte |= (1 << j);
if ((image->cache_map[map_len_bytes - 1] & last_byte) != last_byte)
image->working = 0;
else
memlogf("[INFO] Instantly publishing relayed image '%s' because the local cache copy is complete", image_name);
}
close(fd);
}
}
} // end cache_file handling
return image;
error:
// Free stuff. Some pointers might be zero, but calling free() on those is safe.
free(image->cache_map);
free(image->config_group);
free(image->low_name);
free(image->file);
free(image->cache_file);
g_free(image);
return NULL;
}
/**
* Iterate over all images and delete them if appropriate.
*/
void dnbd3_exec_delete(int save_if_changed)
{
int changed = FALSE;
const time_t now = time(NULL);
GSList *image_iterator, *client_iterator;
char ipstr[100];
printf("[DEBUG] Scanning for deletable images\n");
pthread_spin_lock(&_spinlock);
for (image_iterator = _dnbd3_images; image_iterator; image_iterator = image_iterator->next)
{
dnbd3_image_t *image = image_iterator->data;
int delete_now = TRUE;
if (image->delete_hard != 0 && image->delete_hard < now)
{
printf("[DEBUG] HARD %s\n", image->low_name);
// Drop all clients still using it
for (client_iterator = _dnbd3_clients; client_iterator; client_iterator = client_iterator->next)
{
dnbd3_client_t *client = client_iterator->data;
if (client->image != image)
continue;
// Kill client's connection
*ipstr = '\0';
host_to_string(&client->host, ipstr, 100);
memlogf("[INFO] delete_hard of %s reached; dropping client %s", image->config_group, ipstr);
const int fd = client->sock;
client->sock = -1;
close(fd);
delete_now = FALSE; // Wait for all clients being actually dropped; deletion will happen on next dnbd3_exec_delete()
}
} // END delete_hard image
else if (image->delete_soft != 0 && image->delete_soft < now && image->atime + 3600 < now)
{
printf("[DEBUG] SOFT %s\n", image->low_name);
// Image should be soft-deleted
// Check if it is still in use
for (client_iterator = _dnbd3_clients; client_iterator; client_iterator = client_iterator->next)
{
const dnbd3_client_t *client = client_iterator->data;
if (client->image == image)
{
// Yep, still in use, keep it
delete_now = FALSE;
break;
}
}
}
else // Neither hard nor soft delete, keep it
{
delete_now = FALSE;
}
if (delete_now)
{
// Image was not in use and should be deleted, free it!
memlogf("[INFO] Freeing end-of-life image %s", image->config_group);
changed = TRUE;
_dnbd3_images = g_slist_remove(_dnbd3_images, image); // Remove from image list
g_key_file_remove_group(_config_handle, image->config_group, NULL); // Also remove from config file
// Free any allocated memory
free(image->cache_map);
free(image->config_group);
free(image->low_name);
free(image->file);
free(image->cache_file);
g_free(image);
// Restart iteration as it would be messed up now
image_iterator = _dnbd3_images;
if (image_iterator == NULL)
break;
}
} // END image iteration
pthread_spin_unlock(&_spinlock);
if (changed && save_if_changed)
dnbd3_save_config();
}
/**
* Return pointer to trusted_server matching given address.
* If not found and create_if_not_found is TRUE, a new entry will be created,
* added to the list and then returned
* Returns NULL otherwise, or if the address could not be parsed
* !! Lock before calling this function !!
*/
dnbd3_trusted_server_t *dnbd3_get_trusted_server(char *address, char create_if_not_found, char *comment)
{
dnbd3_trusted_server_t server;
memset(&server, 0, sizeof(server));
if (!parse_address(address, &server.host))
{
memlogf("[WARNING] Could not parse address '%s' of trusted server", address);
return NULL;
}
#ifndef WITH_IPV6
if (server.host.type == AF_INET6)
{
printf("[DEBUG] Ignoring IPv6 trusted server.\n");
return NULL;
}
#endif
GSList *iterator;
for (iterator = _trusted_servers; iterator; iterator = iterator->next)
{
dnbd3_trusted_server_t *comp = iterator->data;
if (is_same_server(&comp->host, &server.host))
return comp;
}
if (!create_if_not_found)
return NULL;
char *groupname = NULL;
if (comment == NULL)
{
groupname = malloc(50);
snprintf(groupname, 50, "trust:%x%x", rand(), (int)clock());
}
else
{
const size_t len = strlen(comment) + 8;
groupname = malloc(len);
snprintf(groupname, len, "trust:%s", comment);
}
char addrbuffer[50];
host_to_string(&server.host, addrbuffer, 50);
g_key_file_set_string(_config_handle, groupname, "address", addrbuffer);
dnbd3_trusted_server_t *copy = malloc(sizeof(server));
memcpy(copy, &server, sizeof(*copy));
copy->comment = strdup(groupname+6);
_trusted_servers = g_slist_prepend(_trusted_servers, copy);
free(groupname);
return copy;
}
/**
* Add new trusted namespace to given trusted server, using given flags.
* Overwrites any existing entry for the given server and namespace
* !! Lock before calling this function !!
*/
int dnbd3_add_trusted_namespace(dnbd3_trusted_server_t *server, char *namespace, char *flags)
{
int nslen = strlen(namespace) + 1;
char nslow[nslen];
memcpy(nslow, namespace, nslen);
remove_trailing_slash(nslow);
strtolower(nslow);
GSList *iterator;
dnbd3_namespace_t *ns = NULL;
for (iterator = server->namespaces; iterator; iterator = iterator->next)
{
dnbd3_namespace_t *cmp = iterator->data;
if (strcmp(nslow, cmp->name) == 0)
{
ns = cmp;
break;
}
}
if (ns == NULL)
{
ns = calloc(1, sizeof(*ns));
ns->name = strdup(nslow);
server->namespaces = g_slist_prepend(server->namespaces, ns);
}
ns->auto_replicate = (flags && strstr(flags, "replicate"));
ns->recursive = (flags && strstr(flags, "recursive"));
size_t len = strlen(server->comment) + 7;
char groupname[len];
snprintf(groupname, len, "trust:%s", server->comment);
if (ns->auto_replicate && ns->recursive)
g_key_file_set_string(_config_handle, groupname, ns->name, "replicate,recursive");
else if (ns->auto_replicate)
g_key_file_set_string(_config_handle, groupname, ns->name, "replicate");
else if (ns->recursive)
g_key_file_set_string(_config_handle, groupname, ns->name, "recursive");
else
g_key_file_set_string(_config_handle, groupname, ns->name, "-");
return TRUE;
}
/**
* Remove trusted namespace from given trusted server.
* !! Lock before calling this function !!
* @return TRUE if element could be removed
* !! Assume that the _trusted_servers list changed after calling this,
* since the trusted server gets removed from it if this was the last namespace
* it contained
*/
int dnbd3_del_trusted_namespace(dnbd3_trusted_server_t *server, char *namespace)
{
int nslen = strlen(namespace) + 1;
char nslow[nslen];
memcpy(nslow, namespace, nslen);
remove_trailing_slash(nslow);
strtolower(nslow);
GSList *iterator;
for (iterator = server->namespaces; iterator; iterator = iterator->next)
{
dnbd3_namespace_t *cmp = iterator->data;
if (strcmp(nslow, cmp->name) == 0)
{
// TODO: Remove from config file
free(cmp->name);
free(cmp);
server->namespaces = g_slist_remove(server->namespaces, cmp);
if (server->namespaces == NULL)
{
g_free(server->comment);
_trusted_servers = g_slist_remove(_trusted_servers, server);
free(server);
}
return TRUE;
}
}
return FALSE;
}
/**
* Gives the closest match of a namespace rule that can be applied to
* the given namespace
* Returns NULL if none
* !! Lock before calling this function !!
*/
dnbd3_namespace_t *dnbd3_get_trust_level(dnbd3_host_t *host, char *namespace)
{
dnbd3_trusted_server_t *server = NULL;
GSList *iterator;
for (iterator = _trusted_servers; iterator; iterator = iterator->next)
{
dnbd3_trusted_server_t *comp = iterator->data;
if (!is_same_server(host, &comp->host))
continue;
server = comp;
break;
}
if (server == NULL)
return NULL;
dnbd3_namespace_t *best = NULL;
int bestlen = 0;
char nslow[strlen(namespace)+1];
strcpy(nslow, namespace);
remove_trailing_slash(nslow);
strtolower(nslow);
for (iterator = server->namespaces; iterator; iterator = iterator-> next)
{
dnbd3_namespace_t *comp = iterator->data;
const int cmplen = strlen(comp->name);
if (strncmp(nslow, comp->name, cmplen) != 0) // names do not match at all
continue;
if (nslow[cmplen] == '/' && !comp->recursive) // partial match, but recursion is disabled
continue;
if (nslow[cmplen] != '\0' && nslow[cmplen] != '/') // in mid-string
continue;
if (cmplen < bestlen) // Match is not better than one found before
continue;
bestlen = cmplen;
best = comp;
}
return best;
}
