/* * Copyright (C) 1999-2001 Internet Software Consortium. * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ /* $ISC: journal.c,v 1.77.2.1 2001/10/15 04:57:51 marka Exp $ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * When true, accept IXFR difference sequences where the * SOA serial number does not change (BIND 8 sends such * sequences). */ static isc_boolean_t bind8_compat = ISC_TRUE; /* XXX config */ /**************************************************************************/ /* * Miscellaneous utilities. */ #define JOURNAL_COMMON_LOGARGS \ dns_lctx, DNS_LOGCATEGORY_GENERAL, DNS_LOGMODULE_JOURNAL #define JOURNAL_DEBUG_LOGARGS(n) \ JOURNAL_COMMON_LOGARGS, ISC_LOG_DEBUG(n) /* * It would be non-sensical (or at least obtuse) to use FAIL() with an * ISC_R_SUCCESS code, but the test is there to keep the Solaris compiler * from complaining about "end-of-loop code not reached". */ #define FAIL(code) \ do { result = (code); \ if (result != ISC_R_SUCCESS) goto failure; \ } while (0) #define CHECK(op) \ do { result = (op); \ if (result != ISC_R_SUCCESS) goto failure; \ } while (0) static inline isc_uint32_t decode_uint32(unsigned char *p) { return ((p[0] << 24) + (p[1] << 16) + (p[2] << 8) + (p[3] << 0)); } static inline void encode_uint32(isc_uint32_t val, unsigned char *p) { p[0] = (isc_uint8_t)(val >> 24); p[1] = (isc_uint8_t)(val >> 16); p[2] = (isc_uint8_t)(val >> 8); p[3] = (isc_uint8_t)(val >> 0); } isc_result_t dns_db_createsoatuple(dns_db_t *db, dns_dbversion_t *ver, isc_mem_t *mctx, dns_diffop_t op, dns_difftuple_t **tp) { isc_result_t result; dns_dbnode_t *node; dns_rdataset_t rdataset; dns_rdata_t rdata = DNS_RDATA_INIT; dns_name_t *zonename; zonename = dns_db_origin(db); node = NULL; result = dns_db_findnode(db, zonename, ISC_FALSE, &node); if (result != ISC_R_SUCCESS) goto nonode; dns_rdataset_init(&rdataset); result = dns_db_findrdataset(db, node, ver, dns_rdatatype_soa, 0, (isc_stdtime_t)0, &rdataset, NULL); if (result != ISC_R_SUCCESS) goto freenode; result = dns_rdataset_first(&rdataset); if (result != ISC_R_SUCCESS) goto freenode; dns_rdataset_current(&rdataset, &rdata); result = dns_difftuple_create(mctx, op, zonename, rdataset.ttl, &rdata, tp); dns_rdataset_disassociate(&rdataset); dns_db_detachnode(db, &node); return (ISC_R_SUCCESS); freenode: dns_db_detachnode(db, &node); nonode: UNEXPECTED_ERROR(__FILE__, __LINE__, "missing SOA"); return (result); } /**************************************************************************/ /* * Journalling. */ /* * A journal file consists of * * - A fixed-size header of type journal_rawheader_t. * * - The index. This is an unordered array of index entries * of type journal_rawpos_t giving the locations * of some arbitrary subset of the journal's addressable * transactions. The index entries are used as hints to * speed up the process of locating a transaction with a given * serial number. Unused index entries have an "offset" * field of zero. The size of the index can vary between * journal files, but does not change during the lifetime * of a file. The size can be zero. * * - The journal data. This consists of one or more transactions. * Each transaction begins with a transaction header of type * journal_rawxhdr_t. The transaction header is followed by a * sequence of RRs, similar in structure to an IXFR difference * sequence (RFC1995). That is, the pre-transaction SOA, * zero or more other deleted RRs, the post-transaction SOA, * and zero or more other added RRs. Unlike in IXFR, each RR * is prefixed with a 32-bit length. * * The journal data part grows as new transactions are * appended to the file. Only those transactions * whose serial number is current-(2^31-1) to current * are considered "addressable" and may be pointed * to from the header or index. They may be preceded * by old transactions that are no longer addressable, * and they may be followed by transactions that were * appended to the journal but never committed by updating * the "end" position in the header. The latter will * be overwritten when new transactions are added. */ /* * On-disk representation of a "pointer" to a journal entry. * These are used in the journal header to locate the beginning * and end of the journal, and in the journal index to locate * other transactions. */ typedef struct { unsigned char serial[4]; /* SOA serial before update. */ /* * XXXRTH Should offset be 8 bytes? * XXXDCL ... probably, since isc_offset_t is 8 bytes on many OSs. * XXXAG ... but we will not be able to seek >2G anyway on many * platforms as long as we are using fseek() rather * than lseek(). */ unsigned char offset[4]; /* Offset from beginning of file. */ } journal_rawpos_t; /* * The on-disk representation of the journal header. * All numbers are stored in big-endian order. */ /* * The header is of a fixed size, with some spare room for future * extensions. */ #define JOURNAL_HEADER_SIZE 64 /* Bytes. */ typedef union { struct { /* File format version ID. */ unsigned char format[16]; /* Position of the first addressable transaction */ journal_rawpos_t begin; /* Position of the next (yet nonexistent) transaction. */ journal_rawpos_t end; /* Number of index entries following the header. */ unsigned char index_size[4]; } h; /* Pad the header to a fixed size. */ unsigned char pad[JOURNAL_HEADER_SIZE]; } journal_rawheader_t; /* * The on-disk representation of the transaction header. * There is one of these at the beginning of each transaction. */ typedef struct { unsigned char size[4]; /* In bytes, excluding header. */ unsigned char serial0[4]; /* SOA serial before update. */ unsigned char serial1[4]; /* SOA serial after update. */ } journal_rawxhdr_t; /* * The on-disk representation of the RR header. * There is one of these at the beginning of each RR. */ typedef struct { unsigned char size[4]; /* In bytes, excluding header. */ } journal_rawrrhdr_t; /* * The in-core representation of the journal header. */ typedef struct { isc_uint32_t serial; isc_offset_t offset; } journal_pos_t; #define POS_VALID(pos) ((pos).offset != 0) #define POS_INVALIDATE(pos) ((pos).offset = 0, (pos).serial = 0) typedef struct { unsigned char format[16]; journal_pos_t begin; journal_pos_t end; isc_uint32_t index_size; } journal_header_t; /* * The in-core representation of the transaction header. */ typedef struct { isc_uint32_t size; isc_uint32_t serial0; isc_uint32_t serial1; } journal_xhdr_t; /* * The in-core representation of the RR header. */ typedef struct { isc_uint32_t size; } journal_rrhdr_t; /* * Initial contents to store in the header of a newly created * journal file. * * The header starts with the magic string ";BIND LOG V9\n" * to identify the file as a BIND 9 journal file. An ASCII * identification string is used rather than a binary magic * number to be consistent with BIND 8 (BIND 8 journal files * are ASCII text files). */ static journal_header_t initial_journal_header = { ";BIND LOG V9\n", { 0, 0 }, { 0, 0 }, 0 }; #define JOURNAL_EMPTY(h) ((h)->begin.offset == (h)->end.offset) typedef enum { JOURNAL_STATE_INVALID, JOURNAL_STATE_READ, JOURNAL_STATE_WRITE, JOURNAL_STATE_TRANSACTION } journal_state_t; struct dns_journal { unsigned int magic; /* JOUR */ isc_mem_t *mctx; /* Memory context */ journal_state_t state; const char *filename; /* Journal file name */ FILE * fp; /* File handle */ isc_offset_t offset; /* Current file offset */ journal_header_t header; /* In-core journal header */ unsigned char *rawindex; /* In-core buffer for journal index in on-disk format */ journal_pos_t *index; /* In-core journal index */ /* Current transaction state (when writing). */ struct { unsigned int n_soa; /* Number of SOAs seen */ journal_pos_t pos[2]; /* Begin/end position */ } x; /* Iteration state (when reading). */ struct { /* These define the part of the journal we iterate over. */ journal_pos_t bpos; /* Position before first, */ journal_pos_t epos; /* and after last transaction */ /* The rest is iterator state. */ isc_uint32_t current_serial; /* Current SOA serial */ isc_buffer_t source; /* Data from disk */ isc_buffer_t target; /* Data from _fromwire check */ dns_decompress_t dctx; /* Dummy decompression ctx */ dns_name_t name; /* Current domain name */ dns_rdata_t rdata; /* Current rdata */ isc_uint32_t ttl; /* Current TTL */ unsigned int xsize; /* Size of transaction data */ unsigned int xpos; /* Current position in it */ isc_result_t result; /* Result of last call */ } it; }; #define DNS_JOURNAL_MAGIC ISC_MAGIC('J', 'O', 'U', 'R') #define DNS_JOURNAL_VALID(t) ISC_MAGIC_VALID(t, DNS_JOURNAL_MAGIC) static void journal_pos_decode(journal_rawpos_t *raw, journal_pos_t *cooked) { cooked->serial = decode_uint32(raw->serial); cooked->offset = decode_uint32(raw->offset); } static void journal_pos_encode(journal_rawpos_t *raw, journal_pos_t *cooked) { encode_uint32(cooked->serial, raw->serial); encode_uint32(cooked->offset, raw->offset); } static void journal_header_decode(journal_rawheader_t *raw, journal_header_t *cooked) { INSIST(sizeof(cooked->format) == sizeof(raw->h.format)); memcpy(cooked->format, raw->h.format, sizeof(cooked->format)); journal_pos_decode(&raw->h.begin, &cooked->begin); journal_pos_decode(&raw->h.end, &cooked->end); cooked->index_size = decode_uint32(raw->h.index_size); } static void journal_header_encode(journal_header_t *cooked, journal_rawheader_t *raw) { INSIST(sizeof(cooked->format) == sizeof(raw->h.format)); memset(raw->pad, 0, sizeof(raw->pad)); memcpy(raw->h.format, cooked->format, sizeof(raw->h.format)); journal_pos_encode(&raw->h.begin, &cooked->begin); journal_pos_encode(&raw->h.end, &cooked->end); encode_uint32(cooked->index_size, raw->h.index_size); } /* * Journal file I/O subroutines, with error checking and reporting. */ static isc_result_t journal_seek(dns_journal_t *j, isc_uint32_t offset) { isc_result_t result; result = isc_stdio_seek(j->fp, (long)offset, SEEK_SET); if (result != ISC_R_SUCCESS) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: seek: %s", j->filename, isc_result_totext(result)); return (ISC_R_UNEXPECTED); } j->offset = offset; return (ISC_R_SUCCESS); } static isc_result_t journal_read(dns_journal_t *j, void *mem, size_t nbytes) { isc_result_t result; result = isc_stdio_read(mem, 1, nbytes, j->fp, NULL); if (result != ISC_R_SUCCESS) { if (result == ISC_R_EOF) return (ISC_R_NOMORE); isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: read: %s", j->filename, isc_result_totext(result)); return (ISC_R_UNEXPECTED); } j->offset += nbytes; return (ISC_R_SUCCESS); } static isc_result_t journal_write(dns_journal_t *j, void *mem, size_t nbytes) { isc_result_t result; result = isc_stdio_write(mem, 1, nbytes, j->fp, NULL); if (result != ISC_R_SUCCESS) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: write: %s", j->filename, isc_result_totext(result)); return (ISC_R_UNEXPECTED); } j->offset += nbytes; return (ISC_R_SUCCESS); } static isc_result_t journal_fsync(dns_journal_t *j) { isc_result_t result; result = isc_stdio_flush(j->fp); if (result != ISC_R_SUCCESS) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: flush: %s", j->filename, isc_result_totext(result)); return (ISC_R_UNEXPECTED); } result = isc_stdio_sync(j->fp); if (result != ISC_R_SUCCESS) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: fsync: %s", j->filename, isc_result_totext(result)); return (ISC_R_UNEXPECTED); } return (ISC_R_SUCCESS); } /* * Read/write a transaction header at the current file position. */ static isc_result_t journal_read_xhdr(dns_journal_t *j, journal_xhdr_t *xhdr) { journal_rawxhdr_t raw; isc_result_t result; result = journal_read(j, &raw, sizeof(raw)); if (result != ISC_R_SUCCESS) return (result); xhdr->size = decode_uint32(raw.size); xhdr->serial0 = decode_uint32(raw.serial0); xhdr->serial1 = decode_uint32(raw.serial1); return (ISC_R_SUCCESS); } static isc_result_t journal_write_xhdr(dns_journal_t *j, isc_uint32_t size, isc_uint32_t serial0, isc_uint32_t serial1) { journal_rawxhdr_t raw; encode_uint32(size, raw.size); encode_uint32(serial0, raw.serial0); encode_uint32(serial1, raw.serial1); return (journal_write(j, &raw, sizeof(raw))); } /* * Read an RR header at the current file position. */ static isc_result_t journal_read_rrhdr(dns_journal_t *j, journal_rrhdr_t *rrhdr) { journal_rawrrhdr_t raw; isc_result_t result; result = journal_read(j, &raw, sizeof(raw)); if (result != ISC_R_SUCCESS) return (result); rrhdr->size = decode_uint32(raw.size); return (ISC_R_SUCCESS); } static isc_result_t journal_file_create(isc_mem_t *mctx, const char *filename) { FILE *fp = NULL; isc_result_t result; journal_header_t header; journal_rawheader_t rawheader; int index_size = 56; /* XXX configurable */ int size; void *mem; /* Memory for temporary index image. */ INSIST(sizeof(journal_rawheader_t) == JOURNAL_HEADER_SIZE); result = isc_stdio_open(filename, "wb", &fp); if (result != ISC_R_SUCCESS) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: create: %s", filename, isc_result_totext(result)); return (ISC_R_UNEXPECTED); } header = initial_journal_header; header.index_size = index_size; journal_header_encode(&header, &rawheader); size = sizeof(journal_rawheader_t) + index_size * sizeof(journal_rawpos_t); mem = isc_mem_get(mctx, size); if (mem == NULL) { (void)isc_stdio_close(fp); (void)isc_file_remove(filename); return (ISC_R_NOMEMORY); } memset(mem, 0, size); memcpy(mem, &rawheader, sizeof(rawheader)); result = isc_stdio_write(mem, 1, (size_t) size, fp, NULL); if (result != ISC_R_SUCCESS) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: write: %s", filename, isc_result_totext(result)); (void)isc_stdio_close(fp); (void)isc_file_remove(filename); isc_mem_put(mctx, mem, size); return (ISC_R_UNEXPECTED); } isc_mem_put(mctx, mem, size); result = isc_stdio_close(fp); if (result != ISC_R_SUCCESS) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: close: %s", filename, isc_result_totext(result)); (void)isc_file_remove(filename); return (ISC_R_UNEXPECTED); } return (ISC_R_SUCCESS); } isc_result_t dns_journal_open(isc_mem_t *mctx, const char *filename, isc_boolean_t write, dns_journal_t **journalp) { FILE *fp = NULL; isc_result_t result; journal_rawheader_t rawheader; dns_journal_t *j; INSIST(journalp != NULL && *journalp == NULL); j = isc_mem_get(mctx, sizeof(*j)); if (j == NULL) return (ISC_R_NOMEMORY); j->mctx = mctx; j->state = JOURNAL_STATE_INVALID; j->fp = NULL; j->filename = filename; j->index = NULL; j->rawindex = NULL; result = isc_stdio_open(j->filename, write ? "rb+" : "rb", &fp); if (result == ISC_R_FILENOTFOUND) { if (write) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_INFO, "journal file %s does not exist, " "creating it", j->filename); CHECK(journal_file_create(mctx, filename)); /* * Retry. */ result = isc_stdio_open(j->filename, "rb+", &fp); } else { FAIL(ISC_R_NOTFOUND); } } if (result != ISC_R_SUCCESS) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: open: %s", j->filename, isc_result_totext(result)); FAIL(ISC_R_UNEXPECTED); } j->fp = fp; /* * Set magic early so that seek/read can succeed. */ j->magic = DNS_JOURNAL_MAGIC; CHECK(journal_seek(j, 0)); CHECK(journal_read(j, &rawheader, sizeof(rawheader))); if (memcmp(rawheader.h.format, initial_journal_header.format, sizeof(initial_journal_header.format)) != 0) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: journal format not recognized", j->filename); FAIL(ISC_R_UNEXPECTED); } journal_header_decode(&rawheader, &j->header); /* * If there is an index, read the raw index into a dynamically * allocated buffer and then convert it into a cooked index. */ if (j->header.index_size != 0) { unsigned int i; unsigned int rawbytes; unsigned char *p; rawbytes = j->header.index_size * sizeof(journal_rawpos_t); j->rawindex = isc_mem_get(mctx, rawbytes); if (j->rawindex == NULL) FAIL(ISC_R_NOMEMORY); CHECK(journal_read(j, j->rawindex, rawbytes)); j->index = isc_mem_get(mctx, j->header.index_size * sizeof(journal_pos_t)); if (j->index == NULL) FAIL(ISC_R_NOMEMORY); p = j->rawindex; for (i = 0; i < j->header.index_size; i++) { j->index[i].serial = decode_uint32(p); p += 4; j->index[i].offset = decode_uint32(p); p += 4; } INSIST(p == j->rawindex + rawbytes); } j->offset = -1; /* Invalid, must seek explicitly. */ /* * Initialize the iterator. */ dns_name_init(&j->it.name, NULL); dns_rdata_init(&j->it.rdata); /* * Set up empty initial buffers for uncheched and checked * wire format RR data. They will be reallocated * later. */ isc_buffer_init(&j->it.source, NULL, 0); isc_buffer_init(&j->it.target, NULL, 0); dns_decompress_init(&j->it.dctx, -1, DNS_DECOMPRESS_NONE); j->state = write ? JOURNAL_STATE_WRITE : JOURNAL_STATE_READ; *journalp = j; return (ISC_R_SUCCESS); failure: j->magic = 0; if (j->index != NULL) { isc_mem_put(j->mctx, j->index, j->header.index_size * sizeof(journal_rawpos_t)); j->index = NULL; } if (j->fp != NULL) (void)isc_stdio_close(j->fp); isc_mem_put(j->mctx, j, sizeof(*j)); return (result); } /* * A comparison function defining the sorting order for * entries in the IXFR-style journal file. * * The IXFR format requires that deletions are sorted before * additions, and within either one, SOA records are sorted * before others. * * Also sort the non-SOA records by type as a courtesy to the * server receiving the IXFR - it may help reduce the amount of * rdataset merging it has to do. */ static int ixfr_order(const void *av, const void *bv) { dns_difftuple_t const * const *ap = av; dns_difftuple_t const * const *bp = bv; dns_difftuple_t const *a = *ap; dns_difftuple_t const *b = *bp; int r; r = (b->op == DNS_DIFFOP_DEL) - (a->op == DNS_DIFFOP_DEL); if (r != 0) return (r); r = (b->rdata.type == dns_rdatatype_soa) - (a->rdata.type == dns_rdatatype_soa); if (r != 0) return (r); r = (a->rdata.type - b->rdata.type); return (r); } /* * Advance '*pos' to the next journal transaction. * * Requires: * *pos refers to a valid journal transaction. * * Ensures: * When ISC_R_SUCCESS is returned, * *pos refers to the next journal transaction. * * Returns one of: * * ISC_R_SUCCESS * ISC_R_NOMORE *pos pointed at the last transaction * Other results due to file errors are possible. */ static isc_result_t journal_next(dns_journal_t *j, journal_pos_t *pos) { isc_result_t result; journal_xhdr_t xhdr; REQUIRE(DNS_JOURNAL_VALID(j)); result = journal_seek(j, pos->offset); if (result != ISC_R_SUCCESS) return (result); /* * Read the header of the current transaction. * This will return ISC_R_NOMORE if we are at EOF. */ result = journal_read_xhdr(j, &xhdr); if (result != ISC_R_SUCCESS) return (result); /* * Check serial number consistency. */ if (xhdr.serial0 != pos->serial) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: journal file corrupt: " "expected serial %u, got %u", j->filename, pos->serial, xhdr.serial0); return (ISC_R_UNEXPECTED); } /* * Check for offset wraparound. */ if ((isc_offset_t)(pos->offset + sizeof(journal_rawxhdr_t) + xhdr.size) < pos->offset) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: offset too large", j->filename); return (ISC_R_UNEXPECTED); } pos->offset += sizeof(journal_rawxhdr_t) + xhdr.size; pos->serial = xhdr.serial1; return (ISC_R_SUCCESS); } /* * If the index of the journal 'j' contains an entry "better" * than '*best_guess', replace '*best_guess' with it. * * "Better" means having a serial number closer to 'serial' * but not greater than 'serial'. */ static void index_find(dns_journal_t *j, isc_uint32_t serial, journal_pos_t *best_guess) { unsigned int i; if (j->index == NULL) return; for (i = 0; i < j->header.index_size; i++) { if (POS_VALID(j->index[i]) && DNS_SERIAL_GE(serial, j->index[i].serial) && DNS_SERIAL_GT(j->index[i].serial, best_guess->serial)) *best_guess = j->index[i]; } } /* * Add a new index entry. If there is no room, make room by removing * the odd-numbered entries and compacting the others into the first * half of the index. This decimates old index entries exponentially * over time, so that the index always contains a much larger fraction * of recent serial numbers than of old ones. This is deliberate - * most index searches are for outgoing IXFR, and IXFR tends to request * recent versions more often than old ones. */ static void index_add(dns_journal_t *j, journal_pos_t *pos) { unsigned int i; if (j->index == NULL) return; /* * Search for a vacant position. */ for (i = 0; i < j->header.index_size; i++) { if (! POS_VALID(j->index[i])) break; } if (i == j->header.index_size) { unsigned int k = 0; /* * Found no vacant position. Make some room. */ for (i = 0; i < j->header.index_size; i += 2) { j->index[k++] = j->index[i]; } i = k; /* 'i' identifies the first vacant position. */ while (k < j->header.index_size) { POS_INVALIDATE(j->index[k]); k++; } } INSIST(i < j->header.index_size); INSIST(! POS_VALID(j->index[i])); /* * Store the new index entry. */ j->index[i] = *pos; } /* * Invalidate any existing index entries that could become * ambiguous when a new transaction with number 'serial' is added. */ static void index_invalidate(dns_journal_t *j, isc_uint32_t serial) { unsigned int i; if (j->index == NULL) return; for (i = 0; i < j->header.index_size; i++) { if (! DNS_SERIAL_GT(serial, j->index[i].serial)) POS_INVALIDATE(j->index[i]); } } /* * Try to find a transaction with initial serial number 'serial' * in the journal 'j'. * * If found, store its position at '*pos' and return ISC_R_SUCCESS. * * If 'serial' is current (= the ending serial number of the * last transaction in the journal), set '*pos' to * the position immediately following the last transaction and * return ISC_R_SUCCESS. * * If 'serial' is within the range of addressable serial numbers * covered by the journal but that particular serial number is missing * (from the journal, not just from the index), return ISC_R_NOTFOUND. * * If 'serial' is outside the range of addressable serial numbers * covered by the journal, return ISC_R_RANGE. * */ static isc_result_t journal_find(dns_journal_t *j, isc_uint32_t serial, journal_pos_t *pos) { isc_result_t result; journal_pos_t current_pos; REQUIRE(DNS_JOURNAL_VALID(j)); if (DNS_SERIAL_GT(j->header.begin.serial, serial)) return (ISC_R_RANGE); if (DNS_SERIAL_GT(serial, j->header.end.serial)) return (ISC_R_RANGE); if (serial == j->header.end.serial) { *pos = j->header.end; return (ISC_R_SUCCESS); } current_pos = j->header.begin; index_find(j, serial, ¤t_pos); while (current_pos.serial != serial) { if (DNS_SERIAL_GT(current_pos.serial, serial)) return (ISC_R_NOTFOUND); result = journal_next(j, ¤t_pos); if (result != ISC_R_SUCCESS) return (result); } *pos = current_pos; return (ISC_R_SUCCESS); } isc_result_t dns_journal_begin_transaction(dns_journal_t *j) { isc_uint32_t offset; isc_result_t result; journal_rawxhdr_t hdr; REQUIRE(DNS_JOURNAL_VALID(j)); REQUIRE(j->state == JOURNAL_STATE_WRITE); /* * Find the file offset where the new transaction should * be written, and seek there. */ if (JOURNAL_EMPTY(&j->header)) { offset = sizeof(journal_rawheader_t) + j->header.index_size * sizeof(journal_rawpos_t); } else { offset = j->header.end.offset; } j->x.pos[0].offset = offset; j->x.pos[1].offset = offset; /* Initial value, will be incremented. */ j->x.n_soa = 0; CHECK(journal_seek(j, offset)); /* * Write a dummy transaction header of all zeroes to reserve * space. It will be filled in when the transaction is * finished. */ memset(&hdr, 0, sizeof(hdr)); CHECK(journal_write(j, &hdr, sizeof(hdr))); j->x.pos[1].offset = j->offset; j->state = JOURNAL_STATE_TRANSACTION; result = ISC_R_SUCCESS; failure: return (result); } isc_result_t dns_journal_writediff(dns_journal_t *j, dns_diff_t *diff) { dns_difftuple_t *t; isc_buffer_t buffer; void *mem = NULL; unsigned int size; isc_result_t result; isc_region_t used; REQUIRE(DNS_DIFF_VALID(diff)); REQUIRE(j->state == JOURNAL_STATE_TRANSACTION); isc_log_write(JOURNAL_DEBUG_LOGARGS(3), "writing to journal"); dns_diff_print(diff, NULL); /* * Pass 1: determine the buffer size needed, and * keep track of SOA serial numbers. */ size = 0; for (t = ISC_LIST_HEAD(diff->tuples); t != NULL; t = ISC_LIST_NEXT(t, link)) { if (t->rdata.type == dns_rdatatype_soa) { if (j->x.n_soa < 2) j->x.pos[j->x.n_soa].serial = dns_soa_getserial(&t->rdata); j->x.n_soa++; } size += sizeof(journal_rawrrhdr_t); size += t->name.length; /* XXX should have access macro? */ size += 10; size += t->rdata.length; } mem = isc_mem_get(j->mctx, size); if (mem == NULL) return (ISC_R_NOMEMORY); isc_buffer_init(&buffer, mem, size); /* * Pass 2. Write RRs to buffer. */ for (t = ISC_LIST_HEAD(diff->tuples); t != NULL; t = ISC_LIST_NEXT(t, link)) { /* * Write the RR header. */ isc_buffer_putuint32(&buffer, t->name.length + 10 + t->rdata.length); /* * Write the owner name, RR header, and RR data. */ isc_buffer_putmem(&buffer, t->name.ndata, t->name.length); isc_buffer_putuint16(&buffer, t->rdata.type); isc_buffer_putuint16(&buffer, t->rdata.rdclass); isc_buffer_putuint32(&buffer, t->ttl); INSIST(t->rdata.length < 65536); isc_buffer_putuint16(&buffer, (isc_uint16_t)t->rdata.length); INSIST(isc_buffer_availablelength(&buffer) >= t->rdata.length); isc_buffer_putmem(&buffer, t->rdata.data, t->rdata.length); } isc_buffer_usedregion(&buffer, &used); INSIST(used.length == size); j->x.pos[1].offset += used.length; /* * Write the buffer contents to the journal file. */ CHECK(journal_write(j, used.base, used.length)); result = ISC_R_SUCCESS; failure: if (mem != NULL) isc_mem_put(j->mctx, mem, size); return (result); } isc_result_t dns_journal_commit(dns_journal_t *j) { isc_result_t result; journal_rawheader_t rawheader; REQUIRE(DNS_JOURNAL_VALID(j)); REQUIRE(j->state == JOURNAL_STATE_TRANSACTION); /* * Perform some basic consistency checks. */ if (j->x.n_soa != 2) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "malformed transaction: %d SOAs", j->x.n_soa); return (ISC_R_UNEXPECTED); } if (! (DNS_SERIAL_GT(j->x.pos[1].serial, j->x.pos[0].serial) || (bind8_compat && j->x.pos[1].serial == j->x.pos[0].serial))) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "malformed transaction: serial number " "would decrease"); return (ISC_R_UNEXPECTED); } if (! JOURNAL_EMPTY(&j->header)) { if (j->x.pos[0].serial != j->header.end.serial) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "malformed transaction: " "%s last serial %u != " "transaction first serial %u", j->filename, j->header.end.serial, j->x.pos[0].serial); return (ISC_R_UNEXPECTED); } } /* * Some old journal entries may become non-addressable * when we increment the current serial number. Purge them * by stepping header.begin forward to the first addressable * transaction. Also purge them from the index. */ if (! JOURNAL_EMPTY(&j->header)) { while (! DNS_SERIAL_GT(j->x.pos[1].serial, j->header.begin.serial)) { CHECK(journal_next(j, &j->header.begin)); } index_invalidate(j, j->x.pos[1].serial); } #ifdef notyet if (DNS_SERIAL_GT(last_dumped_serial, j->x.pos[1].serial)) { force_dump(...); } #endif /* * Commit the transaction data to stable storage. */ CHECK(journal_fsync(j)); /* * Update the transaction header. */ CHECK(journal_seek(j, j->x.pos[0].offset)); CHECK(journal_write_xhdr(j, (j->x.pos[1].offset - j->x.pos[0].offset) - sizeof(journal_rawxhdr_t), j->x.pos[0].serial, j->x.pos[1].serial)); /* * Update the journal header. */ if (JOURNAL_EMPTY(&j->header)) { j->header.begin = j->x.pos[0]; } j->header.end = j->x.pos[1]; journal_header_encode(&j->header, &rawheader); CHECK(journal_seek(j, 0)); CHECK(journal_write(j, &rawheader, sizeof(rawheader))); /* * Update the index. */ index_add(j, &j->x.pos[0]); /* * Convert the index into on-disk format and write * it to disk. */ if (j->header.index_size != 0) { unsigned int i; unsigned char *p; unsigned int rawbytes; rawbytes = j->header.index_size * sizeof(journal_rawpos_t); p = j->rawindex; for (i = 0; i < j->header.index_size; i++) { encode_uint32(j->index[i].serial, p); p += 4; encode_uint32(j->index[i].offset, p); p += 4; } INSIST(p == j->rawindex + rawbytes); CHECK(journal_write(j, j->rawindex, rawbytes)); } /* * Commit the header to stable storage. */ CHECK(journal_fsync(j)); /* * We no longer have a transaction open. */ j->state = JOURNAL_STATE_WRITE; result = ISC_R_SUCCESS; failure: return (result); } isc_result_t dns_journal_write_transaction(dns_journal_t *j, dns_diff_t *diff) { isc_result_t result; CHECK(dns_diff_sort(diff, ixfr_order)); CHECK(dns_journal_begin_transaction(j)); CHECK(dns_journal_writediff(j, diff)); CHECK(dns_journal_commit(j)); result = ISC_R_SUCCESS; failure: return (result); } void dns_journal_destroy(dns_journal_t **journalp) { dns_journal_t *j = *journalp; REQUIRE(DNS_JOURNAL_VALID(j)); j->it.result = ISC_R_FAILURE; dns_name_invalidate(&j->it.name); dns_decompress_invalidate(&j->it.dctx); if (j->rawindex != NULL) isc_mem_put(j->mctx, j->rawindex, j->header.index_size * sizeof(journal_rawpos_t)); if (j->index != NULL) isc_mem_put(j->mctx, j->index, j->header.index_size * sizeof(journal_pos_t)); if (j->it.target.base != NULL) isc_mem_put(j->mctx, j->it.target.base, j->it.target.length); if (j->it.source.base != NULL) isc_mem_put(j->mctx, j->it.source.base, j->it.source.length); if (j->fp != NULL) (void)isc_stdio_close(j->fp); j->magic = 0; isc_mem_put(j->mctx, j, sizeof(*j)); *journalp = NULL; } /* * Roll the open journal 'j' into the database 'db'. * A new database version will be created. */ /* XXX Share code with incoming IXFR? */ static isc_result_t roll_forward(dns_journal_t *j, dns_db_t *db) { isc_buffer_t source; /* Transaction data from disk */ isc_buffer_t target; /* Ditto after _fromwire check */ isc_uint32_t db_serial; /* Database SOA serial */ isc_uint32_t end_serial; /* Last journal SOA serial */ isc_result_t result; dns_dbversion_t *ver = NULL; journal_pos_t pos; dns_diff_t diff; unsigned int n_soa = 0; unsigned int n_put = 0; REQUIRE(DNS_JOURNAL_VALID(j)); REQUIRE(DNS_DB_VALID(db)); dns_diff_init(j->mctx, &diff); /* * Set up empty initial buffers for uncheched and checked * wire format transaction data. They will be reallocated * later. */ isc_buffer_init(&source, NULL, 0); isc_buffer_init(&target, NULL, 0); /* * Create the new database version. */ CHECK(dns_db_newversion(db, &ver)); /* * Get the current database SOA serial number. */ CHECK(dns_db_getsoaserial(db, ver, &db_serial)); /* * Locate a journal entry for the current database serial. */ CHECK(journal_find(j, db_serial, &pos)); /* * XXX do more drastic things, like marking zone stale, * if this fails? */ /* * XXXRTH The zone code should probably mark the zone as bad and * scream loudly into the log if this is a dynamic update * log reply that failed. */ end_serial = dns_journal_last_serial(j); if (db_serial == end_serial) CHECK(DNS_R_UPTODATE); CHECK(dns_journal_iter_init(j, db_serial, end_serial)); for (result = dns_journal_first_rr(j); result == ISC_R_SUCCESS; result = dns_journal_next_rr(j)) { dns_name_t *name; isc_uint32_t ttl; dns_rdata_t *rdata; dns_difftuple_t *tuple = NULL; name = NULL; rdata = NULL; dns_journal_current_rr(j, &name, &ttl, &rdata); if (rdata->type == dns_rdatatype_soa) n_soa++; if (n_soa == 3) n_soa = 1; if (n_soa == 0) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: journal file corrupt: missing " "initial SOA", j->filename); FAIL(ISC_R_UNEXPECTED); } CHECK(dns_difftuple_create(diff.mctx, n_soa == 1 ? DNS_DIFFOP_DEL : DNS_DIFFOP_ADD, name, ttl, rdata, &tuple)); dns_diff_append(&diff, &tuple); if (++n_put > 100) { isc_log_write(JOURNAL_DEBUG_LOGARGS(3), "applying diff to database"); dns_diff_print(&diff, NULL); CHECK(dns_diff_apply(&diff, db, ver)); dns_diff_clear(&diff); n_put = 0; } } if (result == ISC_R_NOMORE) result = ISC_R_SUCCESS; CHECK(result); if (n_put != 0) { isc_log_write(JOURNAL_DEBUG_LOGARGS(3), "applying final diff to database"); dns_diff_print(&diff, NULL); CHECK(dns_diff_apply(&diff, db, ver)); dns_diff_clear(&diff); } failure: if (ver != NULL) dns_db_closeversion(db, &ver, result == ISC_R_SUCCESS ? ISC_TRUE : ISC_FALSE); if (source.base != NULL) isc_mem_put(j->mctx, source.base, source.length); if (target.base != NULL) isc_mem_put(j->mctx, target.base, target.length); dns_diff_clear(&diff); return (result); } isc_result_t dns_journal_rollforward(isc_mem_t *mctx, dns_db_t *db, const char *filename) { dns_journal_t *j; isc_result_t result; REQUIRE(DNS_DB_VALID(db)); REQUIRE(filename != NULL); j = NULL; result = dns_journal_open(mctx, filename, ISC_FALSE, &j); if (result == ISC_R_NOTFOUND) { isc_log_write(JOURNAL_DEBUG_LOGARGS(3), "no journal file, but that's OK"); return (DNS_R_NOJOURNAL); } if (result != ISC_R_SUCCESS) return (result); if (JOURNAL_EMPTY(&j->header)) result = DNS_R_UPTODATE; else result = roll_forward(j, db); dns_journal_destroy(&j); return (result); } isc_result_t dns_journal_print(isc_mem_t *mctx, const char *filename, FILE *file) { dns_journal_t *j; isc_buffer_t source; /* Transaction data from disk */ isc_buffer_t target; /* Ditto after _fromwire check */ isc_uint32_t start_serial; /* Database SOA serial */ isc_uint32_t end_serial; /* Last journal SOA serial */ isc_result_t result; dns_diff_t diff; unsigned int n_soa = 0; unsigned int n_put = 0; REQUIRE(filename != NULL); j = NULL; result = dns_journal_open(mctx, filename, ISC_FALSE, &j); if (result == ISC_R_NOTFOUND) { isc_log_write(JOURNAL_DEBUG_LOGARGS(3), "no journal file"); return (DNS_R_NOJOURNAL); } if (result != ISC_R_SUCCESS) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "journal open failure"); return (result); } dns_diff_init(j->mctx, &diff); /* * Set up empty initial buffers for uncheched and checked * wire format transaction data. They will be reallocated * later. */ isc_buffer_init(&source, NULL, 0); isc_buffer_init(&target, NULL, 0); start_serial = dns_journal_first_serial(j); end_serial = dns_journal_last_serial(j); CHECK(dns_journal_iter_init(j, start_serial, end_serial)); for (result = dns_journal_first_rr(j); result == ISC_R_SUCCESS; result = dns_journal_next_rr(j)) { dns_name_t *name; isc_uint32_t ttl; dns_rdata_t *rdata; dns_difftuple_t *tuple = NULL; name = NULL; rdata = NULL; dns_journal_current_rr(j, &name, &ttl, &rdata); if (rdata->type == dns_rdatatype_soa) n_soa++; if (n_soa == 3) n_soa = 1; if (n_soa == 0) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: journal file corrupt: missing " "initial SOA", j->filename); FAIL(ISC_R_UNEXPECTED); } CHECK(dns_difftuple_create(diff.mctx, n_soa == 1 ? DNS_DIFFOP_DEL : DNS_DIFFOP_ADD, name, ttl, rdata, &tuple)); dns_diff_append(&diff, &tuple); if (++n_put > 100) { result = dns_diff_print(&diff, file); dns_diff_clear(&diff); n_put = 0; if (result != ISC_R_SUCCESS) break; } } if (result == ISC_R_NOMORE) result = ISC_R_SUCCESS; CHECK(result); if (n_put != 0) { result = dns_diff_print(&diff, file); dns_diff_clear(&diff); } goto cleanup; failure: isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: cannot print: journal file corrupt", j->filename); cleanup: if (source.base != NULL) isc_mem_put(j->mctx, source.base, source.length); if (target.base != NULL) isc_mem_put(j->mctx, target.base, target.length); dns_diff_clear(&diff); dns_journal_destroy(&j); return (result); } /**************************************************************************/ /* * Miscellaneous accessors. */ isc_uint32_t dns_journal_first_serial(dns_journal_t *j) { return (j->header.begin.serial); } isc_uint32_t dns_journal_last_serial(dns_journal_t *j) { return (j->header.end.serial); } /**************************************************************************/ /* * Iteration support. * * When serving an outgoing IXFR, we transmit a part the journal starting * at the serial number in the IXFR request and ending at the serial * number that is current when the IXFR request arrives. The ending * serial number is not necessarily at the end of the journal: * the journal may grow while the IXFR is in progress, but we stop * when we reach the serial number that was current when the IXFR started. */ static isc_result_t read_one_rr(dns_journal_t *j); /* * Make sure the buffer 'b' is has at least 'size' bytes * allocated, and clear it. * * Requires: * Either b->base is NULL, or it points to b->length bytes of memory * previously allocated by isc_mem_get(). */ static isc_result_t size_buffer(isc_mem_t *mctx, isc_buffer_t *b, unsigned size) { if (b->length < size) { void *mem = isc_mem_get(mctx, size); if (mem == NULL) return (ISC_R_NOMEMORY); if (b->base != NULL) isc_mem_put(mctx, b->base, b->length); b->base = mem; b->length = size; } isc_buffer_clear(b); return (ISC_R_SUCCESS); } isc_result_t dns_journal_iter_init(dns_journal_t *j, isc_uint32_t begin_serial, isc_uint32_t end_serial) { isc_result_t result; CHECK(journal_find(j, begin_serial, &j->it.bpos)); INSIST(j->it.bpos.serial == begin_serial); CHECK(journal_find(j, end_serial, &j->it.epos)); INSIST(j->it.epos.serial == end_serial); result = ISC_R_SUCCESS; failure: j->it.result = result; return (j->it.result); } isc_result_t dns_journal_first_rr(dns_journal_t *j) { isc_result_t result; /* * Seek to the beginning of the first transaction we are * interested in. */ CHECK(journal_seek(j, j->it.bpos.offset)); j->it.current_serial = j->it.bpos.serial; j->it.xsize = 0; /* We have no transaction data yet... */ j->it.xpos = 0; /* ...and haven't used any of it. */ return (read_one_rr(j)); failure: return (result); } static isc_result_t read_one_rr(dns_journal_t *j) { isc_result_t result; dns_rdatatype_t rdtype; dns_rdataclass_t rdclass; unsigned int rdlen; isc_uint32_t ttl; journal_xhdr_t xhdr; journal_rrhdr_t rrhdr; INSIST(j->offset <= j->it.epos.offset); if (j->offset == j->it.epos.offset) return (ISC_R_NOMORE); if (j->it.xpos == j->it.xsize) { /* * We are at a transaction boundary. * Read another transaction header. */ CHECK(journal_read_xhdr(j, &xhdr)); if (xhdr.size == 0) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "journal corrupt: empty transaction"); FAIL(ISC_R_UNEXPECTED); } if (xhdr.serial0 != j->it.current_serial) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: journal file corrupt: " "expected serial %u, got %u", j->filename, j->it.current_serial, xhdr.serial0); FAIL(ISC_R_UNEXPECTED); } j->it.xsize = xhdr.size; j->it.xpos = 0; } /* * Read an RR. */ result = journal_read_rrhdr(j, &rrhdr); /* * Perform a sanity check on the journal RR size. * The smallest possible RR has a 1-byte owner name * and a 10-byte header. The largest possible * RR has 65535 bytes of data, a header, and a maximum- * size owner name, well below 70 k total. */ if (rrhdr.size < 1+10 || rrhdr.size > 70000) { isc_log_write(JOURNAL_COMMON_LOGARGS, ISC_LOG_ERROR, "%s: journal corrupt: impossible RR size " "(%d bytes)", j->filename, rrhdr.size); FAIL(ISC_R_UNEXPECTED); } CHECK(size_buffer(j->mctx, &j->it.source, rrhdr.size)); CHECK(journal_read(j, j->it.source.base, rrhdr.size)); isc_buffer_add(&j->it.source, rrhdr.size); /* * The target buffer is made the same size * as the source buffer, with the assumption that when * no compression in present, the output of dns_*_fromwire() * is no larger than the input. */ CHECK(size_buffer(j->mctx, &j->it.target, rrhdr.size)); /* * Parse the owner name. We don't know where it * ends yet, so we make the entire "remaining" * part of the buffer "active". */ isc_buffer_setactive(&j->it.source, j->it.source.used - j->it.source.current); CHECK(dns_name_fromwire(&j->it.name, &j->it.source, &j->it.dctx, ISC_FALSE, &j->it.target)); /* * Check that the RR header is there, and parse it. */ if (isc_buffer_remaininglength(&j->it.source) < 10) FAIL(DNS_R_FORMERR); rdtype = isc_buffer_getuint16(&j->it.source); rdclass = isc_buffer_getuint16(&j->it.source); ttl = isc_buffer_getuint32(&j->it.source); rdlen = isc_buffer_getuint16(&j->it.source); /* * Parse the rdata. */ isc_buffer_setactive(&j->it.source, rdlen); dns_rdata_reset(&j->it.rdata); CHECK(dns_rdata_fromwire(&j->it.rdata, rdclass, rdtype, &j->it.source, &j->it.dctx, ISC_FALSE, &j->it.target)); j->it.ttl = ttl; j->it.xpos += sizeof(journal_rawrrhdr_t) + rrhdr.size; if (rdtype == dns_rdatatype_soa) { /* XXX could do additional consistency checks here */ j->it.current_serial = dns_soa_getserial(&j->it.rdata); } result = ISC_R_SUCCESS; failure: j->it.result = result; return (result); } isc_result_t dns_journal_next_rr(dns_journal_t *j) { j->it.result = read_one_rr(j); return (j->it.result); } void dns_journal_current_rr(dns_journal_t *j, dns_name_t **name, isc_uint32_t *ttl, dns_rdata_t **rdata) { REQUIRE(j->it.result == ISC_R_SUCCESS); *name = &j->it.name; *ttl = j->it.ttl; *rdata = &j->it.rdata; } /**************************************************************************/ /* * Generating diffs from databases */ /* * Construct a diff containing all the RRs at the current name of the * database iterator 'dbit' in database 'db', version 'ver'. * Set '*name' to the current name, and append the diff to 'diff'. * All new tuples will have the operation 'op'. * * Requires: 'name' must have buffer large enough to hold the name. * Typically, a dns_fixedname_t would be used. */ static isc_result_t get_name_diff(dns_db_t *db, dns_dbversion_t *ver, isc_stdtime_t now, dns_dbiterator_t *dbit, dns_name_t *name, dns_diffop_t op, dns_diff_t *diff) { isc_result_t result; dns_dbnode_t *node = NULL; dns_rdatasetiter_t *rdsiter = NULL; dns_difftuple_t *tuple = NULL; result = dns_dbiterator_current(dbit, &node, name); if (result != ISC_R_SUCCESS) return (result); result = dns_db_allrdatasets(db, node, ver, now, &rdsiter); if (result != ISC_R_SUCCESS) goto cleanup_node; for (result = dns_rdatasetiter_first(rdsiter); result == ISC_R_SUCCESS; result = dns_rdatasetiter_next(rdsiter)) { dns_rdataset_t rdataset; dns_rdataset_init(&rdataset); dns_rdatasetiter_current(rdsiter, &rdataset); for (result = dns_rdataset_first(&rdataset); result == ISC_R_SUCCESS; result = dns_rdataset_next(&rdataset)) { dns_rdata_t rdata = DNS_RDATA_INIT; dns_rdataset_current(&rdataset, &rdata); result = dns_difftuple_create(diff->mctx, op, name, rdataset.ttl, &rdata, &tuple); if (result != ISC_R_SUCCESS) { dns_rdataset_disassociate(&rdataset); goto cleanup_iterator; } dns_diff_append(diff, &tuple); } dns_rdataset_disassociate(&rdataset); if (result != ISC_R_NOMORE) goto cleanup_iterator; } if (result != ISC_R_NOMORE) goto cleanup_iterator; result = ISC_R_SUCCESS; cleanup_iterator: dns_rdatasetiter_destroy(&rdsiter); cleanup_node: dns_db_detachnode(db, &node); return (result); } /* * Comparison function for use by dns_diff_subtract when sorting * the diffs to be subtracted. The sort keys are the rdata type * and the rdata itself. The owner name is ignored, because * it is known to be the same for all tuples. */ static int rdata_order(const void *av, const void *bv) { dns_difftuple_t const * const *ap = av; dns_difftuple_t const * const *bp = bv; dns_difftuple_t const *a = *ap; dns_difftuple_t const *b = *bp; int r; r = (b->rdata.type - a->rdata.type); if (r != 0) return (r); r = dns_rdata_compare(&a->rdata, &b->rdata); return (r); } static isc_result_t dns_diff_subtract(dns_diff_t diff[2], dns_diff_t *r) { isc_result_t result; dns_difftuple_t *p[2]; int i, t; CHECK(dns_diff_sort(&diff[0], rdata_order)); CHECK(dns_diff_sort(&diff[1], rdata_order)); for (;;) { p[0] = ISC_LIST_HEAD(diff[0].tuples); p[1] = ISC_LIST_HEAD(diff[1].tuples); if (p[0] == NULL && p[1] == NULL) break; for (i = 0; i < 2; i++) if (p[!i] == NULL) { ISC_LIST_UNLINK(diff[i].tuples, p[i], link); ISC_LIST_APPEND(r->tuples, p[i], link); goto next; } t = rdata_order(&p[0], &p[1]); if (t < 0) { ISC_LIST_UNLINK(diff[0].tuples, p[0], link); ISC_LIST_APPEND(r->tuples, p[0], link); goto next; } if (t > 0) { ISC_LIST_UNLINK(diff[1].tuples, p[1], link); ISC_LIST_APPEND(r->tuples, p[1], link); goto next; } INSIST(t == 0); /* * Identical RRs in both databases; skip them both. */ for (i = 0; i < 2; i++) { ISC_LIST_UNLINK(diff[i].tuples, p[i], link); dns_difftuple_free(&p[i]); } next: ; } result = ISC_R_SUCCESS; failure: return (result); } /* * Compare the databases 'dba' and 'dbb' and generate a journal * entry containing the changes to make 'dba' from 'dbb' (note * the order). This journal entry will consist of a single, * possibly very large transaction. */ isc_result_t dns_db_diff(isc_mem_t *mctx, dns_db_t *dba, dns_dbversion_t *dbvera, dns_db_t *dbb, dns_dbversion_t *dbverb, const char *journal_filename) { dns_db_t *db[2]; dns_dbversion_t *ver[2]; dns_dbiterator_t *dbit[2] = { NULL, NULL }; isc_boolean_t have[2] = { ISC_FALSE, ISC_FALSE }; dns_fixedname_t fixname[2]; isc_result_t result, itresult[2]; dns_diff_t diff[2], resultdiff; int i, t; dns_journal_t *journal = NULL; db[0] = dba, db[1] = dbb; ver[0] = dbvera, ver[1] = dbverb; dns_diff_init(mctx, &diff[0]); dns_diff_init(mctx, &diff[1]); dns_diff_init(mctx, &resultdiff); dns_fixedname_init(&fixname[0]); dns_fixedname_init(&fixname[1]); CHECK(dns_journal_open(mctx, journal_filename, ISC_TRUE, &journal)); CHECK(dns_db_createiterator(db[0], ISC_FALSE, &dbit[0])); CHECK(dns_db_createiterator(db[1], ISC_FALSE, &dbit[1])); itresult[0] = dns_dbiterator_first(dbit[0]); itresult[1] = dns_dbiterator_first(dbit[1]); for (;;) { for (i = 0; i < 2; i++) { if (! have[i] && itresult[i] == ISC_R_SUCCESS) { CHECK(get_name_diff(db[i], ver[i], 0, dbit[i], dns_fixedname_name(&fixname[i]), i == 0 ? DNS_DIFFOP_ADD : DNS_DIFFOP_DEL, &diff[i])); itresult[i] = dns_dbiterator_next(dbit[i]); have[i] = ISC_TRUE; } } if (! have[0] && ! have[1]) { INSIST(ISC_LIST_EMPTY(diff[0].tuples)); INSIST(ISC_LIST_EMPTY(diff[1].tuples)); break; } for (i = 0; i < 2; i++) { if (! have[!i]) { ISC_LIST_APPENDLIST(resultdiff.tuples, diff[i].tuples, link); INSIST(ISC_LIST_EMPTY(diff[i].tuples)); have[i] = ISC_FALSE; goto next; } } t = dns_name_compare(dns_fixedname_name(&fixname[0]), dns_fixedname_name(&fixname[1])); if (t < 0) { ISC_LIST_APPENDLIST(resultdiff.tuples, diff[0].tuples, link); INSIST(ISC_LIST_EMPTY(diff[0].tuples)); have[0] = ISC_FALSE; continue; } if (t > 0) { ISC_LIST_APPENDLIST(resultdiff.tuples, diff[1].tuples, link); INSIST(ISC_LIST_EMPTY(diff[1].tuples)); have[1] = ISC_FALSE; continue; } INSIST(t == 0); CHECK(dns_diff_subtract(diff, &resultdiff)); INSIST(ISC_LIST_EMPTY(diff[0].tuples)); INSIST(ISC_LIST_EMPTY(diff[1].tuples)); have[0] = have[1] = ISC_FALSE; next: ; } if (itresult[0] != ISC_R_NOMORE) FAIL(itresult[0]); if (itresult[1] != ISC_R_NOMORE) FAIL(itresult[1]); if (ISC_LIST_EMPTY(resultdiff.tuples)) { isc_log_write(JOURNAL_DEBUG_LOGARGS(3), "no changes"); } else { CHECK(dns_journal_write_transaction(journal, &resultdiff)); } INSIST(ISC_LIST_EMPTY(diff[0].tuples)); INSIST(ISC_LIST_EMPTY(diff[1].tuples)); dns_diff_clear(&resultdiff); failure: dns_dbiterator_destroy(&dbit[0]); dns_dbiterator_destroy(&dbit[1]); dns_journal_destroy(&journal); return (result); }