It is now possible to enable/disable RDB checksum computation from redis.conf or...

[redis.git] / src / rdb.c

diff --git a/src/rdb.c b/src/rdb.c
index 1e23fa70cf392b399806ce9a7086af65114dd7c2..8ffd2c28f9d331f864d6aeb3be18ff50bc0b8fe3 100644 (file)
--- a/src/rdb.c
+++ b/src/rdb.c
@@ -1,6 +1,7 @@
 #include "redis.h"
 #include "lzf.h"    /* LZF compression library */
 #include "zipmap.h"
+#include "endianconv.h"
 
 #include <math.h>
 #include <sys/types.h>
@@ -26,11 +27,6 @@ int rdbLoadType(rio *rdb) {
     return type;
 }
 
-int rdbSaveTime(rio *rdb, time_t t) {
-    int32_t t32 = (int32_t) t;
-    return rdbWriteRaw(rdb,&t32,4);
-}
-
 time_t rdbLoadTime(rio *rdb) {
     int32_t t32;
     if (rioRead(rdb,&t32,4) == 0) return -1;
@@ -602,10 +598,12 @@ int rdbSave(char *filename) {
     dictIterator *di = NULL;
     dictEntry *de;
     char tmpfile[256];
+    char magic[10];
     int j;
     long long now = mstime();
     FILE *fp;
     rio rdb;
+    uint64_t cksum;
 
     snprintf(tmpfile,256,"temp-%d.rdb", (int) getpid());
     fp = fopen(tmpfile,"w");
@@ -616,7 +614,10 @@ int rdbSave(char *filename) {
     }
 
     rioInitWithFile(&rdb,fp);
-    if (rdbWriteRaw(&rdb,"REDIS0004",9) == -1) goto werr;
+    if (server.rdb_checksum)
+        rdb.update_cksum = rioGenericUpdateChecksum;
+    snprintf(magic,sizeof(magic),"REDIS%04d",REDIS_RDB_VERSION);
+    if (rdbWriteRaw(&rdb,magic,9) == -1) goto werr;
 
     for (j = 0; j < server.dbnum; j++) {
         redisDb *db = server.db+j;
@@ -644,9 +645,17 @@ int rdbSave(char *filename) {
         }
         dictReleaseIterator(di);
     }
+    di = NULL; /* So that we don't release it again on error. */
+
     /* EOF opcode */
     if (rdbSaveType(&rdb,REDIS_RDB_OPCODE_EOF) == -1) goto werr;
 
+    /* CRC64 checksum. It will be zero if checksum computation is disabled, the
+     * loading code skips the check in this case. */
+    cksum = rdb.cksum;
+    memrev64ifbe(&cksum);
+    rioWrite(&rdb,&cksum,8);
+
     /* Make sure data will not remain on the OS's output buffers */
     fflush(fp);
     fsync(fileno(fp));
@@ -689,7 +698,7 @@ int rdbSaveBackground(char *filename) {
         if (server.ipfd > 0) close(server.ipfd);
         if (server.sofd > 0) close(server.sofd);
         retval = rdbSave(filename);
-        _exit((retval == REDIS_OK) ? 0 : 1);
+        exitFromChild((retval == REDIS_OK) ? 0 : 1);
     } else {
         /* Parent */
         server.stat_fork_time = ustime()-start;
@@ -720,7 +729,7 @@ robj *rdbLoadObject(int rdbtype, rio *rdb) {
     size_t len;
     unsigned int i;
 
-    redisLog(REDIS_DEBUG,"LOADING OBJECT %d (at %d)\n",rdbtype,rdb->tell(rdb));
+    redisLog(REDIS_DEBUG,"LOADING OBJECT %d (at %d)\n",rdbtype,rioTell(rdb));
     if (rdbtype == REDIS_RDB_TYPE_STRING) {
         /* Read string value */
         if ((o = rdbLoadEncodedStringObject(rdb)) == NULL) return NULL;
@@ -1019,6 +1028,8 @@ int rdbLoad(char *filename) {
         return REDIS_ERR;
     }
     rioInitWithFile(&rdb,fp);
+    if (server.rdb_checksum)
+        rdb.update_cksum = rioGenericUpdateChecksum;
     if (rioRead(&rdb,buf,9) == 0) goto eoferr;
     buf[9] = '\0';
     if (memcmp(buf,"REDIS",5) != 0) {
@@ -1028,7 +1039,7 @@ int rdbLoad(char *filename) {
         return REDIS_ERR;
     }
     rdbver = atoi(buf+5);
-    if (rdbver < 1 || rdbver > 4) {
+    if (rdbver < 1 || rdbver > 5) {
         fclose(fp);
         redisLog(REDIS_WARNING,"Can't handle RDB format version %d",rdbver);
         errno = EINVAL;
@@ -1042,7 +1053,7 @@ int rdbLoad(char *filename) {
 
         /* Serve the clients from time to time */
         if (!(loops++ % 1000)) {
-            loadingProgress(rdb.tell(&rdb));
+            loadingProgress(rioTell(&rdb));
             aeProcessEvents(server.el, AE_FILE_EVENTS|AE_DONT_WAIT);
         }
 
@@ -1099,6 +1110,20 @@ int rdbLoad(char *filename) {
 
         decrRefCount(key);
     }
+    /* Verify the checksum if RDB version is >= 5 */
+    if (rdbver >= 5 && server.rdb_checksum) {
+        uint64_t cksum, expected = rdb.cksum;
+
+        if (rioRead(&rdb,&cksum,8) == 0) goto eoferr;
+        memrev64ifbe(&cksum);
+        if (cksum == 0) {
+            redisLog(REDIS_WARNING,"RDB file was saved with checksum disabled: no check performed.");
+        } else if (cksum != expected) {
+            redisLog(REDIS_WARNING,"Wrong RDB checksum. Aborting now.");
+            exit(1);
+        }
+    }
+
     fclose(fp);
     stopLoading();
     return REDIS_OK;