/*
* 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 <netinet/in.h>
#include <arpa/inet.h>
#include "server.h"
#include "utils.h"
#include "memlog.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 char parse_address(char *string, uint8_t *af, uint8_t *addr, uint16_t *port);
static char is_valid_namespace(char *namespace);
static char is_valid_imagename(char *namespace);
static void strtolower(char *string);
static dnbd3_image_t* prepare_image(char *image_name, int rid, char *image_file, char *cache_file, gchar **servers, gsize num_servers);
static int save_config();
//static char* get_local_image_name(char *global_name);
/**
* Parse IPv4 or IPv6 address in string representation to a suitable format usable by the BSD socket library
* @string eg. "1.2.3.4" or "2a01::10:5", optially with port appended, eg "1.2.3.4:6666" or "[2a01::10:5]:6666"
* @af will contain either AF_INET or AF_INET6
* @addr will contain the address in network representation
* @port will contain the port in network representation, defaulting to #define PORT if none was given
* returns 1 on success, 0 in failure. contents of af, addr and port are undefined in the latter case
*/
static char parse_address(char *string, uint8_t *af, uint8_t *addr, uint16_t *port)
{
struct in_addr v4;
struct in6_addr v6;
// Try IPv4 without port
if (1 == inet_pton(AF_INET, string, &v4))
{
*af = AF_INET;
memcpy(addr, &v4, 4);
*port = htons(PORT);
return 1;
}
// Try IPv6 without port
if (1 == inet_pton(AF_INET6, string, &v6))
{
*af = AF_INET6;
memcpy(addr, &v6, 16);
*port = htons(PORT);
return 1;
}
// Scan for port
char *portpos = NULL, *ptr = string;
while (*ptr)
{
if (*ptr == ':')
portpos = ptr;
++ptr;
}
if (portpos == NULL)
return 0; // No port in string
// Consider IP being surrounded by [ ]
if (*string == '[' && *(portpos - 1) == ']')
{
++string;
*(portpos - 1) = '\0';
}
*portpos++ = '\0';
int p = atoi(portpos);
if (p < 1 || p > 65535)
return 0; // Invalid port
*port = htons((uint16_t)p);
// Try IPv4 with port
if (1 == inet_pton(AF_INET, string, &v4))
{
*af = AF_INET;
memcpy(addr, &v4, 4);
return 1;
}
// Try IPv6 with port
if (1 == inet_pton(AF_INET6, string, &v6))
{
*af = AF_INET6;
memcpy(addr, &v6, 16);
return 1;
}
// FAIL
return 0;
}
static char is_valid_namespace(char *namespace)
{
if (*namespace == '\0' || *namespace == '/')
return 0; // Invalid: Length = 0 or starting with a slash
while (*namespace)
{
if (*namespace != '/' && *namespace != '-' && (*namespace < 'a' || *namespace > 'z')
&& (*namespace < 'A' || *namespace > 'Z'))
return 0;
++namespace;
}
if (*(namespace - 1) == '/')
return 0; // Invalid: Ends in a slash
return 1;
}
static char is_valid_imagename(char *namespace)
{
if (*namespace == '\0' || *namespace == ' ')
return 0; // Invalid: Length = 0 or starting with a space
while (*namespace)
{ // Check for invalid chars
if (*namespace != '.' && *namespace != '-' && *namespace != ' ' && *namespace != '(' && *namespace != ')'
&& (*namespace < 'a' || *namespace > 'z') && (*namespace < 'A' || *namespace > 'Z'))
return 0;
++namespace;
}
if (*(namespace - 1) == ' ')
return 0; // Invalid: Ends in a space
return 1;
}
static void strtolower(char *string)
{
while (*string)
{
if (*string >= 'A' && *string <= 'Z')
*string += 32;
++string;
}
}
void dnbd3_load_config()
{
gint i;
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);
}
_local_namespace = g_key_file_get_string(_config_handle, "settings", "default_namespace", NULL);
if (_local_namespace && !is_valid_namespace(_local_namespace))
{
memlogf("[ERROR] Ignoring default namespace: '%s' is not a valid namespace", _local_namespace);
g_free(_local_namespace);
_local_namespace = NULL;
}
_ipc_password = g_key_file_get_string(_config_handle, "settings", "password", NULL);
gchar **groups = NULL;
gsize section_count;
groups = g_key_file_get_groups(_config_handle, §ion_count);
for (i = 0; i < section_count; i++)
{
// Special group, ignore
if (strcmp(groups[i], "settings") == 0 || strcmp(groups[i], "trusted") == 0)
{
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);
gsize num_servers;
gchar **servers = g_key_file_get_string_list(_config_handle, groups[i], "servers", &num_servers, NULL);
pthread_spin_lock(&_spinlock);
dnbd3_image_t *image = prepare_image(groups[i], rid, image_file, cache_file, servers, num_servers);
if (image)
{
_dnbd3_images = g_slist_prepend(_dnbd3_images, image);
}
pthread_spin_unlock(&_spinlock);
g_free(image_file);
g_free(cache_file);
g_strfreev(servers);
}
g_strfreev(groups);
}
int dnbd3_add_image(dnbd3_image_t *image)
{
// Lock here to prevent concurrent add calls to mess rids up. Cannot happen currently
// as IPC 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, NULL, 0);
if (newimage)
{
_dnbd3_images = g_slist_prepend(_dnbd3_images, image);
}
else
{
pthread_spin_unlock(&_spinlock);
return ERROR_SEE_LOG;
}
// Adding image was successful, write config file
g_key_file_set_integer(_config_handle, image->config_group, "rid", image->rid);
g_key_file_set_string(_config_handle, image->config_group, "file", image->file);
//g_key_file_set_string(_config_handle, image->name, "servers", image->serverss); // TODO: Save servers as string
g_key_file_set_string(_config_handle, image->config_group, "cache", image->cache_file);
pthread_spin_unlock(&_spinlock);
const int ret = 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 = 1; // TODO: Configurable.
existing_image->delete_hard = time(NULL) + 86400; // TODO: Configurable
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 = 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;
}
static int 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
int slen;
int islocal = (strchr(name_orig, '/') == NULL);
if (islocal)
slen = strlen(name_orig) + strlen(_local_namespace) + 2;
else
slen = strlen(name_orig) + 1;
char name[slen];
if (islocal)
sprintf(name, "%s/%s", _local_namespace, name_orig);
else
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!\n");
}
void dnbd3_handle_sigterm(int signum)
{
memlogf("INFO: SIGTERM or SIGINT received!\n");
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, gchar **servers, gsize num_servers)
{
int j, k;
if (image_name == NULL)
{
memlogf("[ERROR] Null Image-Name");
return NULL;
}
if (!is_valid_imagename(image_name))
{
memlogf("[ERROR] Invalid image name: '%s'", image_name);
return NULL;
}
if (strchr(image_name, '.') == NULL && _local_namespace == NULL)
{
memlogf("[ERROR] Image '%s' has local name and no default namespace is defined; entry ignored.", image_name);
return NULL;
}
// 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;
}
if (strchr(image_name, '/') == NULL)
{ // Local image, build global name
image->low_name = calloc(strlen(_local_namespace) + strlen(image_name) + 2, sizeof(char));
sprintf(image->low_name, "%s/%s", _local_namespace, image_name);
}
else
{
image->low_name = strdup(image_name);
}
if (dnbd3_get_image(image->low_name, rid, 0))
{
memlogf("[ERROR] Duplicate image in config: '%s' rid:%d", image_name, rid);
goto error;
}
strtolower(image->low_name);
image->config_group = strdup(image_name);
image->rid = rid;
image->relayed = (image_file == NULL || image_file == '\0');
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;
}
// A list of servers that are known to also host or relay this image
if (servers)
for (k = 0, j = 0; j < MIN(num_servers, NUMBER_SERVERS); ++j)
{
if (parse_address(servers[j], &(image->servers[k].hostaddrtype), image->servers[k].hostaddr,
&(image->servers[k].port)))
{
++k;
continue;
}
image->servers[k].hostaddrtype = 0;
}
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)
{
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);
}
/*
// TODO: Do this as soon as a connection to a upstream server is established
// open cache file
fd = open(_images[i].cache_file, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
if (fd < 1)
memlogf("ERROR: Could't create cache file '%s'", _images[i].cache_file);
if (_images[i].filesize != lseek(fd, 0, SEEK_END))
fallocate(fd, 0, 0, _images[i].filesize);
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];
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)
{
// 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';
inet_ntop(client->addrtype, client->ipaddr, 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 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;
}
} // END image iteration
pthread_spin_lock(&_spinlock);
if (changed && save_if_changed)
save_config();
}
/**
* Return local image name for a global image name
* eg. "uni-freiburg/rz/ubuntu 12.04" -> "ubuntu 12.04"
* ONLY IF the local name space really is "uni-freiburg/rz"
* Returns NULL otherwise
* The returned pointer points to memory inside the passed
* string (if not NULL), so do not modify or free
* / <---
static char* get_local_image_name(char *global_name)
{
if (_local_namespace == NULL)
return NULL; // No local namespace defined, so it cannot be local
char *first_slash = strchr(global_name, '/');
if (first_slash == NULL)
return global_name; // Already local
const size_t buflen = strlen(_local_namespace) + 1;
if (first_slash - global_name + 1 != buflen)
return NULL; // Namespaces have different length, cannot be same
char namespace[buflen];
char passedname[buflen];
strcpy(namespace, _local_namespace);
strncpy(passedname, global_name, buflen);
passedname[buflen] = '\0';
strtolower(namespace);
strtolower(passedname);
if (strcmp(namespace, passedname) == 0)
return global_name + buflen; // points somewhere into passed buffer
return NULL;
} //*/