diff options
Diffstat (limited to 'src/redis-check-rdb.c')
| -rw-r--r-- | src/redis-check-rdb.c | 350 |
1 files changed, 350 insertions, 0 deletions
diff --git a/src/redis-check-rdb.c b/src/redis-check-rdb.c new file mode 100644 index 0000000..08be40f --- /dev/null +++ b/src/redis-check-rdb.c @@ -0,0 +1,350 @@ +/* + * Copyright (c) 2016, Salvatore Sanfilippo <antirez at gmail dot com> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * * Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * * Neither the name of Redis nor the names of its contributors may be used + * to endorse or promote products derived from this software without + * specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + */ + +#include "server.h" +#include "rdb.h" + +#include <stdarg.h> + +void createSharedObjects(void); +void rdbLoadProgressCallback(rio *r, const void *buf, size_t len); +long long rdbLoadMillisecondTime(rio *rdb); +int rdbCheckMode = 0; + +struct { + rio *rio; + robj *key; /* Current key we are reading. */ + int key_type; /* Current key type if != -1. */ + unsigned long keys; /* Number of keys processed. */ + unsigned long expires; /* Number of keys with an expire. */ + unsigned long already_expired; /* Number of keys already expired. */ + int doing; /* The state while reading the RDB. */ + int error_set; /* True if error is populated. */ + char error[1024]; +} rdbstate; + +/* At every loading step try to remember what we were about to do, so that + * we can log this information when an error is encountered. */ +#define RDB_CHECK_DOING_START 0 +#define RDB_CHECK_DOING_READ_TYPE 1 +#define RDB_CHECK_DOING_READ_EXPIRE 2 +#define RDB_CHECK_DOING_READ_KEY 3 +#define RDB_CHECK_DOING_READ_OBJECT_VALUE 4 +#define RDB_CHECK_DOING_CHECK_SUM 5 +#define RDB_CHECK_DOING_READ_LEN 6 +#define RDB_CHECK_DOING_READ_AUX 7 + +char *rdb_check_doing_string[] = { + "start", + "read-type", + "read-expire", + "read-key", + "read-object-value", + "check-sum", + "read-len", + "read-aux" +}; + +char *rdb_type_string[] = { + "string", + "list-linked", + "set-hashtable", + "zset-v1", + "hash-hashtable", + "zset-v2", + "module-value", + "","", + "hash-zipmap", + "list-ziplist", + "set-intset", + "zset-ziplist", + "hash-ziplist", + "quicklist" +}; + +/* Show a few stats collected into 'rdbstate' */ +void rdbShowGenericInfo(void) { + printf("[info] %lu keys read\n", rdbstate.keys); + printf("[info] %lu expires\n", rdbstate.expires); + printf("[info] %lu already expired\n", rdbstate.already_expired); +} + +/* Called on RDB errors. Provides details about the RDB and the offset + * we were when the error was detected. */ +void rdbCheckError(const char *fmt, ...) { + char msg[1024]; + va_list ap; + + va_start(ap, fmt); + vsnprintf(msg, sizeof(msg), fmt, ap); + va_end(ap); + + printf("--- RDB ERROR DETECTED ---\n"); + printf("[offset %llu] %s\n", + (unsigned long long) (rdbstate.rio ? + rdbstate.rio->processed_bytes : 0), msg); + printf("[additional info] While doing: %s\n", + rdb_check_doing_string[rdbstate.doing]); + if (rdbstate.key) + printf("[additional info] Reading key '%s'\n", + (char*)rdbstate.key->ptr); + if (rdbstate.key_type != -1) + printf("[additional info] Reading type %d (%s)\n", + rdbstate.key_type, + ((unsigned)rdbstate.key_type < + sizeof(rdb_type_string)/sizeof(char*)) ? + rdb_type_string[rdbstate.key_type] : "unknown"); + rdbShowGenericInfo(); +} + +/* Print informations during RDB checking. */ +void rdbCheckInfo(const char *fmt, ...) { + char msg[1024]; + va_list ap; + + va_start(ap, fmt); + vsnprintf(msg, sizeof(msg), fmt, ap); + va_end(ap); + + printf("[offset %llu] %s\n", + (unsigned long long) (rdbstate.rio ? + rdbstate.rio->processed_bytes : 0), msg); +} + +/* Used inside rdb.c in order to log specific errors happening inside + * the RDB loading internals. */ +void rdbCheckSetError(const char *fmt, ...) { + va_list ap; + + va_start(ap, fmt); + vsnprintf(rdbstate.error, sizeof(rdbstate.error), fmt, ap); + va_end(ap); + rdbstate.error_set = 1; +} + +/* During RDB check we setup a special signal handler for memory violations + * and similar conditions, so that we can log the offending part of the RDB + * if the crash is due to broken content. */ +void rdbCheckHandleCrash(int sig, siginfo_t *info, void *secret) { + UNUSED(sig); + UNUSED(info); + UNUSED(secret); + + rdbCheckError("Server crash checking the specified RDB file!"); + exit(1); +} + +void rdbCheckSetupSignals(void) { + struct sigaction act; + + sigemptyset(&act.sa_mask); + act.sa_flags = SA_NODEFER | SA_RESETHAND | SA_SIGINFO; + act.sa_sigaction = rdbCheckHandleCrash; + sigaction(SIGSEGV, &act, NULL); + sigaction(SIGBUS, &act, NULL); + sigaction(SIGFPE, &act, NULL); + sigaction(SIGILL, &act, NULL); +} + +/* Check the specified RDB file. Return 0 if the RDB looks sane, otherwise + * 1 is returned. */ +int redis_check_rdb(char *rdbfilename) { + uint64_t dbid; + int type, rdbver; + char buf[1024]; + long long expiretime, now = mstime(); + FILE *fp; + static rio rdb; /* Pointed by global struct riostate. */ + + if ((fp = fopen(rdbfilename,"r")) == NULL) return 1; + + rioInitWithFile(&rdb,fp); + rdbstate.rio = &rdb; + rdb.update_cksum = rdbLoadProgressCallback; + if (rioRead(&rdb,buf,9) == 0) goto eoferr; + buf[9] = '\0'; + if (memcmp(buf,"REDIS",5) != 0) { + rdbCheckError("Wrong signature trying to load DB from file"); + return 1; + } + rdbver = atoi(buf+5); + if (rdbver < 1 || rdbver > RDB_VERSION) { + rdbCheckError("Can't handle RDB format version %d",rdbver); + return 1; + } + + startLoading(fp); + while(1) { + robj *key, *val; + expiretime = -1; + + /* Read type. */ + rdbstate.doing = RDB_CHECK_DOING_READ_TYPE; + if ((type = rdbLoadType(&rdb)) == -1) goto eoferr; + + /* Handle special types. */ + if (type == RDB_OPCODE_EXPIRETIME) { + rdbstate.doing = RDB_CHECK_DOING_READ_EXPIRE; + /* EXPIRETIME: load an expire associated with the next key + * to load. Note that after loading an expire we need to + * load the actual type, and continue. */ + if ((expiretime = rdbLoadTime(&rdb)) == -1) goto eoferr; + /* We read the time so we need to read the object type again. */ + rdbstate.doing = RDB_CHECK_DOING_READ_TYPE; + if ((type = rdbLoadType(&rdb)) == -1) goto eoferr; + /* the EXPIRETIME opcode specifies time in seconds, so convert + * into milliseconds. */ + expiretime *= 1000; + } else if (type == RDB_OPCODE_EXPIRETIME_MS) { + /* EXPIRETIME_MS: milliseconds precision expire times introduced + * with RDB v3. Like EXPIRETIME but no with more precision. */ + rdbstate.doing = RDB_CHECK_DOING_READ_EXPIRE; + if ((expiretime = rdbLoadMillisecondTime(&rdb)) == -1) goto eoferr; + /* We read the time so we need to read the object type again. */ + rdbstate.doing = RDB_CHECK_DOING_READ_TYPE; + if ((type = rdbLoadType(&rdb)) == -1) goto eoferr; + } else if (type == RDB_OPCODE_EOF) { + /* EOF: End of file, exit the main loop. */ + break; + } else if (type == RDB_OPCODE_SELECTDB) { + /* SELECTDB: Select the specified database. */ + rdbstate.doing = RDB_CHECK_DOING_READ_LEN; + if ((dbid = rdbLoadLen(&rdb,NULL)) == RDB_LENERR) + goto eoferr; + rdbCheckInfo("Selecting DB ID %d", dbid); + continue; /* Read type again. */ + } else if (type == RDB_OPCODE_RESIZEDB) { + /* RESIZEDB: Hint about the size of the keys in the currently + * selected data base, in order to avoid useless rehashing. */ + uint64_t db_size, expires_size; + rdbstate.doing = RDB_CHECK_DOING_READ_LEN; + if ((db_size = rdbLoadLen(&rdb,NULL)) == RDB_LENERR) + goto eoferr; + if ((expires_size = rdbLoadLen(&rdb,NULL)) == RDB_LENERR) + goto eoferr; + continue; /* Read type again. */ + } else if (type == RDB_OPCODE_AUX) { + /* AUX: generic string-string fields. Use to add state to RDB + * which is backward compatible. Implementations of RDB loading + * are requierd to skip AUX fields they don't understand. + * + * An AUX field is composed of two strings: key and value. */ + robj *auxkey, *auxval; + rdbstate.doing = RDB_CHECK_DOING_READ_AUX; + if ((auxkey = rdbLoadStringObject(&rdb)) == NULL) goto eoferr; + if ((auxval = rdbLoadStringObject(&rdb)) == NULL) goto eoferr; + + rdbCheckInfo("AUX FIELD %s = '%s'", + (char*)auxkey->ptr, (char*)auxval->ptr); + decrRefCount(auxkey); + decrRefCount(auxval); + continue; /* Read type again. */ + } else { + if (!rdbIsObjectType(type)) { + rdbCheckError("Invalid object type: %d", type); + return 1; + } + rdbstate.key_type = type; + } + + /* Read key */ + rdbstate.doing = RDB_CHECK_DOING_READ_KEY; + if ((key = rdbLoadStringObject(&rdb)) == NULL) goto eoferr; + rdbstate.key = key; + rdbstate.keys++; + /* Read value */ + rdbstate.doing = RDB_CHECK_DOING_READ_OBJECT_VALUE; + if ((val = rdbLoadObject(type,&rdb)) == NULL) goto eoferr; + /* Check if the key already expired. This function is used when loading + * an RDB file from disk, either at startup, or when an RDB was + * received from the master. In the latter case, the master is + * responsible for key expiry. If we would expire keys here, the + * snapshot taken by the master may not be reflected on the slave. */ + if (server.masterhost == NULL && expiretime != -1 && expiretime < now) + rdbstate.already_expired++; + if (expiretime != -1) rdbstate.expires++; + rdbstate.key = NULL; + decrRefCount(key); + decrRefCount(val); + rdbstate.key_type = -1; + } + /* Verify the checksum if RDB version is >= 5 */ + if (rdbver >= 5 && server.rdb_checksum) { + uint64_t cksum, expected = rdb.cksum; + + rdbstate.doing = RDB_CHECK_DOING_CHECK_SUM; + if (rioRead(&rdb,&cksum,8) == 0) goto eoferr; + memrev64ifbe(&cksum); + if (cksum == 0) { + rdbCheckInfo("RDB file was saved with checksum disabled: no check performed."); + } else if (cksum != expected) { + rdbCheckError("RDB CRC error"); + } else { + rdbCheckInfo("Checksum OK"); + } + } + + fclose(fp); + return 0; + +eoferr: /* unexpected end of file is handled here with a fatal exit */ + if (rdbstate.error_set) { + rdbCheckError(rdbstate.error); + } else { + rdbCheckError("Unexpected EOF reading RDB file"); + } + return 1; +} + +/* RDB check main: called form redis.c when Redis is executed with the + * redis-check-rdb alias. + * + * The function never returns, but exits with the status code according + * to success (RDB is sane) or error (RDB is corrupted). */ +int redis_check_rdb_main(int argc, char **argv) { + if (argc != 2) { + fprintf(stderr, "Usage: %s <rdb-file-name>\n", argv[0]); + exit(1); + } + /* In order to call the loading functions we need to create the shared + * integer objects, however since this function may be called from + * an already initialized Redis instance, check if we really need to. */ + if (shared.integers[0] == NULL) + createSharedObjects(); + server.loading_process_events_interval_bytes = 0; + rdbCheckMode = 1; + rdbCheckInfo("Checking RDB file %s", argv[1]); + rdbCheckSetupSignals(); + int retval = redis_check_rdb(argv[1]); + if (retval == 0) { + rdbCheckInfo("\\o/ RDB looks OK! \\o/"); + rdbShowGenericInfo(); + } + exit(retval); +} |