/* default for number of ixfr versions in files */
#define IXFR_NUMBER_DEFAULT 5 /* number of versions */
/* default for IXFR storage */
#define IXFR_SIZE_DEFAULT 1048576 /* in bytes, 1M */
/* data structure that stores IXFR contents for a zone. */
struct zone_ixfr {
/* Items are of type ixfr_data. The key is old_serial.
* So it can be looked up on an incoming IXFR. They are sorted
* by old_serial, so the looked up and next are the versions needed.
* Tree of ixfr data for versions */
struct rbtree* data;
/* total size stored at this time, in bytes,
* sum of sizes of the ixfr data elements */
size_t total_size;
/* the oldest serial number in the tree, searchable by old_serial */
uint32_t oldest_serial;
/* the newest serial number in the tree, that is searchable in the
* tree, so it is the old_serial of the newest data entry, that
* has an even newer new_serial of that entry */
uint32_t newest_serial;
};
/* Data structure that stores one IXFR.
* The RRs are stored in uncompressed wireformat, that means
* an uncompressed domain name, type, class, TTL, rdatalen,
* uncompressed rdata in wireformat.
*
* The data structure is formatted like this so that making an IXFR
* that moves across several versions can be done by collating the
* pieces precisely from the versions involved. In particular, for
* an IXFR from olddata to newdata, for a combined output:
* newdata.newsoa olddata.oldsoa olddata.del olddata.add
* newdata.del newdata.add
* in sequence should produce a valid, non-condensed, IXFR with multiple
* versions inside.
*/
struct ixfr_data {
/* Node in the rbtree. Key is oldserial */
struct rbnode node;
/* from what serial the IXFR starts from, the 'old' serial */
uint32_t oldserial;
/* where to IXFR goes to, the 'new' serial */
uint32_t newserial;
/* the new SOA record, with newserial */
uint8_t* newsoa;
/* byte length of the uncompressed wireformat RR in newsoa */
size_t newsoa_len;
/* the old SOA record, with oldserial */
uint8_t* oldsoa;
/* byte length of the uncompressed wireformat RR in oldsoa*/
size_t oldsoa_len;
/* the deleted RRs, ends with the newserial SOA record.
* if the ixfr is collated out multiple versions, then
* this deleted RRs section contains several add and del sections
* for the older versions, and ends with the last del section,
* and the SOA record with the newserial.
* That is everything except the final add section for newserial. */
uint8_t* del;
/* byte length of the uncompressed wireformat RRs in del */
size_t del_len;
/* the added RRs, ends with the newserial SOA record. */
uint8_t* add;
/* byte length of the uncompressed wireformat RRs in add */
size_t add_len;
/* log string (if not NULL) about where data is from */
char* log_str;
/* the number of the ixfr.<num> file on disk. If 0, there is no
* file. If 1, it is file ixfr<nothingafterit>. */
int file_num;
};
/* process queries in IXFR state */
query_state_type query_ixfr(struct nsd *nsd, struct query *query);
/*
* While an IXFR is processed, in incoming IXFR that is downloaded by NSD,
* this structure keeps track of how to store the data from it. That data
* can then be used to answer IXFR queries.
*
* The structure keeps track of allocation data for the IXFR records.
* If it is cancelled, that is flagged so storage stops.
*/
struct ixfr_store {
/* the zone info, with options and zone ixfr reference */
struct zone* zone;
/* are we cancelled, it is not an IXFR, no need to store information
* any more. */
int cancelled;
/* data has been trimmed and newsoa added */
int data_trimmed;
/* the ixfr data that we are storing into */
struct ixfr_data* data;
/* capacity for the delrrs storage, size of ixfr del allocation */
size_t del_capacity;
/* capacity for the addrrs storage, size of ixfr add allocation */
size_t add_capacity;
};
/*
* Start the storage of the IXFR data from this IXFR.
* If it returns NULL, the IXFR storage stops. On malloc failure, the
* storage is returned NULL, or cancelled if failures happen later on.
*
* When done, the finish routine links the data into the memory for the zone.
* If it turns out to not be used, use the cancel routine. Or the free
* routine if the ixfr_store itself needs to be deleted too, like on error.
*
* zone: the zone structure
* ixfr_store_mem: preallocated by caller, used to allocate the store struct.
* old_serial: the start serial of the IXFR.
* new_serial: the end serial of the IXFR.
* return NULL or a fresh ixfr_store structure for adding records to the
* IXFR with this serial number. The NULL is on error.
*/
struct ixfr_store* ixfr_store_start(struct zone* zone,
struct ixfr_store* ixfr_store_mem);
/*
* Cancel the ixfr store in progress. The pointer remains valid, no store done.
* ixfr_store: this is set to cancel.
*/
void ixfr_store_cancel(struct ixfr_store* ixfr_store);
/*
* Free ixfr store structure, it is no longer used.
* ixfr_store: deleted
*/
void ixfr_store_free(struct ixfr_store* ixfr_store);
/*
* Finish ixfr store processing. Links the data into the zone ixfr data.
* ixfr_store: Data is linked into the zone struct. The ixfr_store is freed.
* nsd: nsd structure for allocation region and global options.
* log_buf: log string for the update.
*/
void ixfr_store_finish(struct ixfr_store* ixfr_store, struct nsd* nsd,
char* log_buf);
/* finish just the data activities, trim up the storage and append newsoa */
void ixfr_store_finish_data(struct ixfr_store* ixfr_store);
/*
* Add the new SOA record to the ixfr store.
* ixfr_store: stores ixfr data that is collected.
* ttl: the TTL of the SOA record
* packet: DNS packet that contains the SOA. position restored on function
* exit.
* rrlen: wire rdata length of the SOA.
*/
void ixfr_store_add_newsoa(struct ixfr_store* ixfr_store, uint32_t ttl,
struct buffer* packet, size_t rrlen);
/*
* Add the old SOA record to the ixfr store.
* ixfr_store: stores ixfr data that is collected.
* ttl: the TTL of the SOA record
* packet: DNS packet that contains the SOA. position restored on function
* exit.
* rrlen: wire rdata length of the SOA.
*/
void ixfr_store_add_oldsoa(struct ixfr_store* ixfr_store, uint32_t ttl,
struct buffer* packet, size_t rrlen);
/* an AXFR has been received, the IXFRs do not connect in version number.
* Delete the unconnected IXFRs from memory */
void ixfr_store_delixfrs(struct zone* zone);
/* return if the zone has ixfr storage enabled for it */
int zone_is_ixfr_enabled(struct zone* zone);
/* free the zone_ixfr */
void zone_ixfr_free(struct zone_ixfr* ixfr);
/* make space to fit in the data */
void zone_ixfr_make_space(struct zone_ixfr* ixfr, struct zone* zone,
struct ixfr_data* data, struct ixfr_store* ixfr_store);
/* remove ixfr data from the zone_ixfr */
void zone_ixfr_remove(struct zone_ixfr* ixfr, struct ixfr_data* data);
/* add ixfr data to the zone_ixfr */
void zone_ixfr_add(struct zone_ixfr* ixfr, struct ixfr_data* data, int isnew);
/* find serial number in ixfr list, or NULL if not found */
struct ixfr_data* zone_ixfr_find_serial(struct zone_ixfr* ixfr,
uint32_t qserial);
/* size of the ixfr data */
size_t ixfr_data_size(struct ixfr_data* data);
/* write ixfr contents to file for the zone */
void ixfr_write_to_file(struct zone* zone, const char* zfile);
/* read ixfr contents from file for the zone */
void ixfr_read_from_file(struct nsd* nsd, struct zone* zone, const char* zfile);
/* get the current serial from the zone */
uint32_t zone_get_current_serial(struct zone* zone);
/* write the ixfr data to file */
int ixfr_write_file(struct zone* zone, struct ixfr_data* data,
const char* zfile, int file_num);
/* see if ixfr file exists */
int ixfr_file_exists(const char* zfile, int file_num);
/* rename the ixfr file */
int ixfr_rename_it(const char* zname, const char* zfile, int oldnum,
int oldtemp, int newnum, int newtemp);
/* read the file header of an ixfr file and return serial numbers. */
int ixfr_read_file_header(const char* zname, const char* zfile,
int file_num, uint32_t* oldserial, uint32_t* newserial,
size_t* data_size, int enoent_is_err);
/* unlink an ixfr file */
int ixfr_unlink_it(const char* zname, const char* zfile, int file_num,
int silent_enoent);
/* delete the ixfr files that are too many */
void ixfr_delete_superfluous_files(struct zone* zone, const char* zfile,
int dest_num_files);
