/**
* Copy one cipher_ctx to another. For instance, assuming that read_ctx is a
* fully initialized context, you could copy it to write_ctx and all yet data
* and pass information across
*
* returns SQLITE_OK if initialization was successful
* returns SQLITE_NOMEM if an error occured allocating memory
*/
static int sqlcipher_cipher_ctx_copy(cipher_ctx *target, cipher_ctx *source) {
void *key = target->key;
void *hmac_key = target->hmac_key;
void *provider = target->provider;
void *provider_ctx = target->provider_ctx;
CODEC_TRACE(("sqlcipher_cipher_ctx_copy: entered target=%p, source=%p\n", target, source));
sqlcipher_free(target->pass, target->pass_sz);
sqlcipher_free(target->keyspec, target->keyspec_sz);
memcpy(target, source, sizeof(cipher_ctx));
target->key = key; //restore pointer to previously allocated key data
memcpy(target->key, source->key, CIPHER_MAX_KEY_SZ);
target->hmac_key = hmac_key; //restore pointer to previously allocated hmac key data
memcpy(target->hmac_key, source->hmac_key, CIPHER_MAX_KEY_SZ);
target->provider = provider; // restore pointer to previouly allocated provider;
memcpy(target->provider, source->provider, sizeof(sqlcipher_provider));
target->provider_ctx = provider_ctx; // restore pointer to previouly allocated provider context;
target->provider->ctx_copy(target->provider_ctx, source->provider_ctx);
if(source->pass && source->pass_sz) {
target->pass = sqlcipher_malloc(source->pass_sz);
if(target->pass == NULL) return SQLITE_NOMEM;
memcpy(target->pass, source->pass, source->pass_sz);
}
if(source->keyspec && source->keyspec_sz) {
target->keyspec = sqlcipher_malloc(source->keyspec_sz);
if(target->keyspec == NULL) return SQLITE_NOMEM;
memcpy(target->keyspec, source->keyspec, source->keyspec_sz);
}
return SQLITE_OK;
}
/**
* Free and wipe memory associated with a cipher_ctx, including the allocated
* read_ctx and write_ctx.
*/
void sqlcipher_codec_ctx_free(codec_ctx **iCtx) {
codec_ctx *ctx = *iCtx;
CODEC_TRACE(("codec_ctx_free: entered iCtx=%p\n", iCtx));
sqlcipher_free(ctx->kdf_salt, ctx->kdf_salt_sz);
sqlcipher_free(ctx->hmac_kdf_salt, ctx->kdf_salt_sz);
sqlcipher_free(ctx->buffer, 0);
sqlcipher_cipher_ctx_free(&ctx->read_ctx);
sqlcipher_cipher_ctx_free(&ctx->write_ctx);
sqlcipher_free(ctx, sizeof(codec_ctx));
}
int sqlcipher_register_provider(sqlcipher_provider *p) {
sqlite3_mutex_enter(sqlcipher_provider_mutex);
if(default_provider != NULL && default_provider != p) {
/* only free the current registerd provider if it has been initialized
and it isn't a pointer to the same provider passed to the function
(i.e. protect against a caller calling register twice for the same provider) */
sqlcipher_free(default_provider, sizeof(sqlcipher_provider));
}
default_provider = p;
sqlite3_mutex_leave(sqlcipher_provider_mutex);
return SQLITE_OK;
}
int sqlcipher_codec_ctx_set_pagesize(codec_ctx *ctx, int size) {
/* attempt to free the existing page buffer */
sqlcipher_free(ctx->buffer,ctx->page_sz);
ctx->page_sz = size;
/* pre-allocate a page buffer of PageSize bytes. This will
be used as a persistent buffer for encryption and decryption
operations to avoid overhead of multiple memory allocations*/
ctx->buffer = sqlcipher_malloc(size);
if(ctx->buffer == NULL) return SQLITE_NOMEM;
return SQLITE_OK;
}
/**
* Set the passphrase for the cipher_ctx
*
* returns SQLITE_OK if assignment was successfull
* returns SQLITE_NOMEM if an error occured allocating memory
*/
static int sqlcipher_cipher_ctx_set_pass(cipher_ctx *ctx, const void *zKey, int nKey) {
/* free, zero existing pointers and size */
sqlcipher_free(ctx->pass, ctx->pass_sz);
ctx->pass = NULL;
ctx->pass_sz = 0;
if(zKey && nKey) { /* if new password is provided, copy it */
ctx->pass_sz = nKey;
ctx->pass = sqlcipher_malloc(nKey);
if(ctx->pass == NULL) return SQLITE_NOMEM;
memcpy(ctx->pass, zKey, nKey);
}
return SQLITE_OK;
}
/**
* Free and wipe memory associated with a cipher_ctx
*/
static void sqlcipher_cipher_ctx_free(cipher_ctx **iCtx) {
cipher_ctx *ctx = *iCtx;
CODEC_TRACE(("cipher_ctx_free: entered iCtx=%p\n", iCtx));
ctx->provider->ctx_free(&ctx->provider_ctx);
sqlcipher_free(ctx->provider, sizeof(sqlcipher_provider));
sqlcipher_free(ctx->key, ctx->key_sz);
sqlcipher_free(ctx->hmac_key, ctx->key_sz);
sqlcipher_free(ctx->pass, ctx->pass_sz);
sqlcipher_free(ctx->keyspec, ctx->keyspec_sz);
sqlcipher_free(ctx, sizeof(cipher_ctx));
}
/**
* Set the keyspec for the cipher_ctx
*
* returns SQLITE_OK if assignment was successfull
* returns SQLITE_NOMEM if an error occured allocating memory
*/
static int sqlcipher_cipher_ctx_set_keyspec(cipher_ctx *ctx, const unsigned char *key, int key_sz, const unsigned char *salt, int salt_sz) {
/* free, zero existing pointers and size */
sqlcipher_free(ctx->keyspec, ctx->keyspec_sz);
ctx->keyspec = NULL;
ctx->keyspec_sz = 0;
/* establic a hex-formated key specification, containing the raw encryption key and
the salt used to generate it */
ctx->keyspec_sz = ((key_sz + salt_sz) * 2) + 3;
ctx->keyspec = sqlcipher_malloc(ctx->keyspec_sz);
if(ctx->keyspec == NULL) return SQLITE_NOMEM;
ctx->keyspec[0] = 'x';
ctx->keyspec[1] = '\'';
cipher_bin2hex(key, key_sz, ctx->keyspec + 2);
cipher_bin2hex(salt, salt_sz, ctx->keyspec + (key_sz * 2) + 2);
ctx->keyspec[ctx->keyspec_sz - 1] = '\'';
return SQLITE_OK;
}
void sqlcipher_deactivate() {
sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
sqlcipher_activate_count--;
/* if no connections are using sqlcipher, cleanup globals */
if(sqlcipher_activate_count < 1) {
sqlite3_mutex_enter(sqlcipher_provider_mutex);
if(default_provider != NULL) {
sqlcipher_free(default_provider, sizeof(sqlcipher_provider));
default_provider = NULL;
}
sqlite3_mutex_leave(sqlcipher_provider_mutex);
/* last connection closed, free provider mutex*/
sqlite3_mutex_free(sqlcipher_provider_mutex);
sqlcipher_provider_mutex = NULL;
sqlcipher_activate_count = 0; /* reset activation count */
}
sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
}
int sqlcipher_codec_add_random(codec_ctx *ctx, const char *zRight, int random_sz){
const char *suffix = &zRight[random_sz-1];
int n = random_sz - 3; /* adjust for leading x' and tailing ' */
if (n > 0 &&
sqlite3StrNICmp((const char *)zRight ,"x'", 2) == 0 &&
sqlite3StrNICmp(suffix, "'", 1) == 0 &&
n % 2 == 0) {
int rc = 0;
int buffer_sz = n / 2;
unsigned char *random;
const unsigned char *z = (const unsigned char *)zRight + 2; /* adjust lead offset of x' */
CODEC_TRACE(("sqlcipher_codec_add_random: using raw random blob from hex\n"));
random = sqlcipher_malloc(buffer_sz);
memset(random, 0, buffer_sz);
cipher_hex2bin(z, n, random);
rc = ctx->read_ctx->provider->add_random(ctx->read_ctx->provider_ctx, random, buffer_sz);
sqlcipher_free(random, buffer_sz);
return rc;
}
return SQLITE_ERROR;
}
static int sqlcipher_openssl_ctx_free(void **ctx) {
sqlcipher_openssl_deactivate(*ctx);
sqlcipher_free(*ctx, sizeof(openssl_ctx));
return SQLITE_OK;
}
int sqlcipher_codec_ctx_migrate(codec_ctx *ctx) {
u32 meta;
int rc = 0;
int command_idx = 0;
int password_sz;
int saved_flags;
int saved_nChange;
int saved_nTotalChange;
void (*saved_xTrace)(void*,const char*);
Db *pDb = 0;
sqlite3 *db = ctx->pBt->db;
const char *db_filename = sqlite3_db_filename(db, "main");
char *migrated_db_filename = sqlite3_mprintf("%s-migrated", db_filename);
char *pragma_hmac_off = "PRAGMA cipher_use_hmac = OFF;";
char *pragma_4k_kdf_iter = "PRAGMA kdf_iter = 4000;";
char *pragma_1x_and_4k;
char *set_user_version;
char *key;
int key_sz;
int user_version = 0;
int upgrade_1x_format = 0;
int upgrade_4k_format = 0;
static const unsigned char aCopy[] = {
BTREE_SCHEMA_VERSION, 1, /* Add one to the old schema cookie */
BTREE_DEFAULT_CACHE_SIZE, 0, /* Preserve the default page cache size */
BTREE_TEXT_ENCODING, 0, /* Preserve the text encoding */
BTREE_USER_VERSION, 0, /* Preserve the user version */
BTREE_APPLICATION_ID, 0, /* Preserve the application id */
};
key_sz = ctx->read_ctx->pass_sz + 1;
key = sqlcipher_malloc(key_sz);
memset(key, 0, key_sz);
memcpy(key, ctx->read_ctx->pass, ctx->read_ctx->pass_sz);
if(db_filename){
const char* commands[5];
char *attach_command = sqlite3_mprintf("ATTACH DATABASE '%s-migrated' as migrate KEY '%q';",
db_filename, key);
int rc = sqlcipher_check_connection(db_filename, key, ctx->read_ctx->pass_sz, "", &user_version);
if(rc == SQLITE_OK){
CODEC_TRACE(("No upgrade required - exiting\n"));
goto exit;
}
// Version 2 - check for 4k with hmac format
rc = sqlcipher_check_connection(db_filename, key, ctx->read_ctx->pass_sz, pragma_4k_kdf_iter, &user_version);
if(rc == SQLITE_OK) {
CODEC_TRACE(("Version 2 format found\n"));
upgrade_4k_format = 1;
}
// Version 1 - check both no hmac and 4k together
pragma_1x_and_4k = sqlite3_mprintf("%s%s", pragma_hmac_off,
pragma_4k_kdf_iter);
rc = sqlcipher_check_connection(db_filename, key, ctx->read_ctx->pass_sz, pragma_1x_and_4k, &user_version);
sqlite3_free(pragma_1x_and_4k);
if(rc == SQLITE_OK) {
CODEC_TRACE(("Version 1 format found\n"));
upgrade_1x_format = 1;
upgrade_4k_format = 1;
}
if(upgrade_1x_format == 0 && upgrade_4k_format == 0) {
CODEC_TRACE(("Upgrade format not determined\n"));
goto handle_error;
}
set_user_version = sqlite3_mprintf("PRAGMA migrate.user_version = %d;", user_version);
commands[0] = upgrade_4k_format == 1 ? pragma_4k_kdf_iter : "";
commands[1] = upgrade_1x_format == 1 ? pragma_hmac_off : "";
commands[2] = attach_command;
commands[3] = "SELECT sqlcipher_export('migrate');";
commands[4] = set_user_version;
for(command_idx = 0; command_idx < ArraySize(commands); command_idx++){
const char *command = commands[command_idx];
if(strcmp(command, "") == 0){
continue;
}
rc = sqlite3_exec(db, command, NULL, NULL, NULL);
if(rc != SQLITE_OK){
break;
}
}
sqlite3_free(attach_command);
sqlite3_free(set_user_version);
sqlcipher_free(key, key_sz);
if(rc == SQLITE_OK){
Btree *pDest;
Btree *pSrc;
int i = 0;
if( !db->autoCommit ){
CODEC_TRACE(("cannot migrate from within a transaction"));
goto handle_error;
}
if( db->nVdbeActive>1 ){
CODEC_TRACE(("cannot migrate - SQL statements in progress"));
goto handle_error;
}
/* Save the current value of the database flags so that it can be
** restored before returning. Then set the writable-schema flag, and
** disable CHECK and foreign key constraints. */
saved_flags = db->flags;
saved_nChange = db->nChange;
saved_nTotalChange = db->nTotalChange;
saved_xTrace = db->xTrace;
db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks | SQLITE_PreferBuiltin;
db->flags &= ~(SQLITE_ForeignKeys | SQLITE_ReverseOrder);
db->xTrace = 0;
pDest = db->aDb[0].pBt;
pDb = &(db->aDb[db->nDb-1]);
pSrc = pDb->pBt;
rc = sqlite3_exec(db, "BEGIN;", NULL, NULL, NULL);
rc = sqlite3BtreeBeginTrans(pSrc, 2);
rc = sqlite3BtreeBeginTrans(pDest, 2);
assert( 1==sqlite3BtreeIsInTrans(pDest) );
assert( 1==sqlite3BtreeIsInTrans(pSrc) );
sqlite3CodecGetKey(db, db->nDb - 1, (void**)&key, &password_sz);
sqlite3CodecAttach(db, 0, key, password_sz);
sqlite3pager_get_codec(pDest->pBt->pPager, (void**)&ctx);
ctx->skip_read_hmac = 1;
for(i=0; i<ArraySize(aCopy); i+=2){
sqlite3BtreeGetMeta(pSrc, aCopy[i], &meta);
rc = sqlite3BtreeUpdateMeta(pDest, aCopy[i], meta+aCopy[i+1]);
if( NEVER(rc!=SQLITE_OK) ) goto handle_error;
}
rc = sqlite3BtreeCopyFile(pDest, pSrc);
ctx->skip_read_hmac = 0;
if( rc!=SQLITE_OK ) goto handle_error;
rc = sqlite3BtreeCommit(pDest);
db->flags = saved_flags;
db->nChange = saved_nChange;
db->nTotalChange = saved_nTotalChange;
db->xTrace = saved_xTrace;
db->autoCommit = 1;
if( pDb ){
sqlite3BtreeClose(pDb->pBt);
pDb->pBt = 0;
pDb->pSchema = 0;
}
sqlite3ResetAllSchemasOfConnection(db);
remove(migrated_db_filename);
sqlite3_free(migrated_db_filename);
} else {
CODEC_TRACE(("*** migration failure** \n\n"));
}
}
goto exit;
handle_error:
CODEC_TRACE(("An error occurred attempting to migrate the database\n"));
rc = SQLITE_ERROR;
exit:
return rc;
}
static int sqlcipher_ltc_ctx_free(void **ctx) {
sqlcipher_ltc_deactivate(&ctx);
sqlcipher_free(*ctx, sizeof(ltc_ctx));
return SQLITE_OK;
}
