sqlcipher/src/crypto.c at Xcode5 · securitykernel/sqlcipher · GitHub

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** SQLCipher

** http://sqlcipher.net

** 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 the ZETETIC LLC 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 ZETETIC LLC ''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 ZETETIC LLC 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.

/* BEGIN SQLCIPHER */

#ifdef SQLITE_HAS_CODEC

#include <assert.h>

#include "sqliteInt.h"

#include "btreeInt.h"

#include "crypto.h"

static const char* codec_get_cipher_version() {

return CIPHER_VERSION;

}

/* Generate code to return a string value */

static void codec_vdbe_return_static_string(Parse *pParse, const char *zLabel, const char *value){

Vdbe *v = sqlite3GetVdbe(pParse);

sqlite3VdbeSetNumCols(v, 1);

sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLabel, SQLITE_STATIC);

sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, value, 0);

sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);

}

static int codec_set_btree_to_codec_pagesize(sqlite3 *db, Db *pDb, codec_ctx *ctx) {

int rc, page_sz, reserve_sz;

page_sz = sqlcipher_codec_ctx_get_pagesize(ctx);

reserve_sz = sqlcipher_codec_ctx_get_reservesize(ctx);

sqlite3_mutex_enter(db->mutex);

db->nextPagesize = page_sz;

/* before forcing the page size we need to unset the BTS_PAGESIZE_FIXED flag, else

sqliteBtreeSetPageSize will block the change */

pDb->pBt->pBt->btsFlags &= ~BTS_PAGESIZE_FIXED;

CODEC_TRACE(("codec_set_btree_to_codec_pagesize: sqlite3BtreeSetPageSize() size=%d reserve=%d\n", page_sz, reserve_sz));

rc = sqlite3BtreeSetPageSize(pDb->pBt, page_sz, reserve_sz, 0);

sqlite3_mutex_leave(db->mutex);

return rc;

}

static int codec_set_pass_key(sqlite3* db, int nDb, const void *zKey, int nKey, int for_ctx) {

struct Db *pDb = &db->aDb[nDb];

CODEC_TRACE(("codec_set_pass_key: entered db=%p nDb=%d zKey=%s nKey=%d for_ctx=%d\n", db, nDb, (char *)zKey, nKey, for_ctx));

if(pDb->pBt) {

codec_ctx *ctx;

sqlite3pager_get_codec(pDb->pBt->pBt->pPager, (void **) &ctx);

if(ctx) return sqlcipher_codec_ctx_set_pass(ctx, zKey, nKey, for_ctx);

}

return SQLITE_ERROR;

}

int sqlcipher_codec_pragma(sqlite3* db, int iDb, Parse *pParse, const char *zLeft, const char *zRight) {

struct Db *pDb = &db->aDb[iDb];

codec_ctx *ctx = NULL;

int rc;

if(pDb->pBt) {

sqlite3pager_get_codec(pDb->pBt->pBt->pPager, (void **) &ctx);

}

CODEC_TRACE(("sqlcipher_codec_pragma: entered db=%p iDb=%d pParse=%p zLeft=%s zRight=%s ctx=%p\n", db, iDb, pParse, zLeft, zRight, ctx));

if( sqlite3StrICmp(zLeft, "cipher_migrate")==0 && !zRight ){

if(ctx){

char *migrate_status = sqlite3_mprintf("%d", sqlcipher_codec_ctx_migrate(ctx));

codec_vdbe_return_static_string(pParse, "sqlcipher_migrate", migrate_status);

sqlite3_free(migrate_status);

}

} else

if( sqlite3StrICmp(zLeft, "cipher_provider")==0 && !zRight ){

if(ctx) { codec_vdbe_return_static_string(pParse, "cipher_provider",

sqlcipher_codec_get_cipher_provider(ctx));

}

} else

if( sqlite3StrICmp(zLeft, "cipher_version")==0 && !zRight ){

codec_vdbe_return_static_string(pParse, "cipher_version", codec_get_cipher_version());

}else

if( sqlite3StrICmp(zLeft, "cipher")==0 ){

if(ctx) {

if( zRight ) {

sqlcipher_codec_ctx_set_cipher(ctx, zRight, 2); // change cipher for both

}else {

codec_vdbe_return_static_string(pParse, "cipher",

sqlcipher_codec_ctx_get_cipher(ctx, 2));

}

}else

if( sqlite3StrICmp(zLeft, "rekey_cipher")==0 && zRight ){

if(ctx) sqlcipher_codec_ctx_set_cipher(ctx, zRight, 1); // change write cipher only

}else

if( sqlite3StrICmp(zLeft,"cipher_default_kdf_iter")==0 ){

if( zRight ) {

sqlcipher_set_default_kdf_iter(atoi(zRight)); // change default KDF iterations

} else {

char *kdf_iter = sqlite3_mprintf("%d", sqlcipher_get_default_kdf_iter());

codec_vdbe_return_static_string(pParse, "cipher_default_kdf_iter", kdf_iter);

sqlite3_free(kdf_iter);

}

}else

if( sqlite3StrICmp(zLeft, "kdf_iter")==0 ){

if(ctx) {

if( zRight ) {

sqlcipher_codec_ctx_set_kdf_iter(ctx, atoi(zRight), 2); // change of RW PBKDF2 iteration

} else {

char *kdf_iter = sqlite3_mprintf("%d", sqlcipher_codec_ctx_get_kdf_iter(ctx, 2));

codec_vdbe_return_static_string(pParse, "kdf_iter", kdf_iter);

sqlite3_free(kdf_iter);

}

}else

if( sqlite3StrICmp(zLeft, "fast_kdf_iter")==0){

if(ctx) {

if( zRight ) {

sqlcipher_codec_ctx_set_fast_kdf_iter(ctx, atoi(zRight), 2); // change of RW PBKDF2 iteration

} else {

char *fast_kdf_iter = sqlite3_mprintf("%d", sqlcipher_codec_ctx_get_fast_kdf_iter(ctx, 2));

codec_vdbe_return_static_string(pParse, "fast_kdf_iter", fast_kdf_iter);

sqlite3_free(fast_kdf_iter);

}

}else

if( sqlite3StrICmp(zLeft, "rekey_kdf_iter")==0 && zRight ){

if(ctx) sqlcipher_codec_ctx_set_kdf_iter(ctx, atoi(zRight), 1); // write iterations only

}else

if( sqlite3StrICmp(zLeft,"cipher_page_size")==0 ){

if(ctx) {

if( zRight ) {

int size = atoi(zRight);

rc = sqlcipher_codec_ctx_set_pagesize(ctx, size);

if(rc != SQLITE_OK) sqlcipher_codec_ctx_set_error(ctx, rc);

rc = codec_set_btree_to_codec_pagesize(db, pDb, ctx);

if(rc != SQLITE_OK) sqlcipher_codec_ctx_set_error(ctx, rc);

} else {

char * page_size = sqlite3_mprintf("%d", sqlcipher_codec_ctx_get_pagesize(ctx));

codec_vdbe_return_static_string(pParse, "cipher_page_size", page_size);

sqlite3_free(page_size);

}

}else

if( sqlite3StrICmp(zLeft,"cipher_default_use_hmac")==0 ){

if( zRight ) {

sqlcipher_set_default_use_hmac(sqlite3GetBoolean(zRight,1));

} else {

char *default_use_hmac = sqlite3_mprintf("%d", sqlcipher_get_default_use_hmac());

codec_vdbe_return_static_string(pParse, "cipher_default_use_hmac", default_use_hmac);

sqlite3_free(default_use_hmac);

}

}else

if( sqlite3StrICmp(zLeft,"cipher_use_hmac")==0 ){

if(ctx) {

if( zRight ) {

rc = sqlcipher_codec_ctx_set_use_hmac(ctx, sqlite3GetBoolean(zRight,1));

if(rc != SQLITE_OK) sqlcipher_codec_ctx_set_error(ctx, rc);

/* since the use of hmac has changed, the page size may also change */

rc = codec_set_btree_to_codec_pagesize(db, pDb, ctx);

if(rc != SQLITE_OK) sqlcipher_codec_ctx_set_error(ctx, rc);

} else {

char *hmac_flag = sqlite3_mprintf("%d", sqlcipher_codec_ctx_get_use_hmac(ctx, 2));

codec_vdbe_return_static_string(pParse, "cipher_use_hmac", hmac_flag);

sqlite3_free(hmac_flag);

}

}else

if( sqlite3StrICmp(zLeft,"cipher_hmac_pgno")==0 ){

if(ctx) {

if(zRight) {

// clear both pgno endian flags

if(sqlite3StrICmp(zRight, "le") == 0) {

sqlcipher_codec_ctx_unset_flag(ctx, CIPHER_FLAG_BE_PGNO);

sqlcipher_codec_ctx_set_flag(ctx, CIPHER_FLAG_LE_PGNO);

} else if(sqlite3StrICmp(zRight, "be") == 0) {

sqlcipher_codec_ctx_unset_flag(ctx, CIPHER_FLAG_LE_PGNO);

sqlcipher_codec_ctx_set_flag(ctx, CIPHER_FLAG_BE_PGNO);

} else if(sqlite3StrICmp(zRight, "native") == 0) {

sqlcipher_codec_ctx_unset_flag(ctx, CIPHER_FLAG_LE_PGNO);

sqlcipher_codec_ctx_unset_flag(ctx, CIPHER_FLAG_BE_PGNO);

}

} else {

if(sqlcipher_codec_ctx_get_flag(ctx, CIPHER_FLAG_LE_PGNO, 2)) {

codec_vdbe_return_static_string(pParse, "cipher_hmac_pgno", "le");

} else if(sqlcipher_codec_ctx_get_flag(ctx, CIPHER_FLAG_BE_PGNO, 2)) {

codec_vdbe_return_static_string(pParse, "cipher_hmac_pgno", "be");

} else {

codec_vdbe_return_static_string(pParse, "cipher_hmac_pgno", "native");

}

}else

if( sqlite3StrICmp(zLeft,"cipher_hmac_salt_mask")==0 ){

if(ctx) {

if(zRight) {

if (sqlite3StrNICmp(zRight ,"x'", 2) == 0 && sqlite3Strlen30(zRight) == 5) {

unsigned char mask = 0;

const char *hex = zRight+2;

cipher_hex2bin(hex,2,&mask);

sqlcipher_set_hmac_salt_mask(mask);

}

} else {

char *hmac_salt_mask = sqlite3_mprintf("%02x", sqlcipher_get_hmac_salt_mask());

codec_vdbe_return_static_string(pParse, "cipher_hmac_salt_mask", hmac_salt_mask);

sqlite3_free(hmac_salt_mask);

}

}else {

return 0;

}

return 1;

}

* sqlite3Codec can be called in multiple modes.

* encrypt mode - expected to return a pointer to the

* encrypted data without altering pData.

* decrypt mode - expected to return a pointer to pData, with

* the data decrypted in the input buffer

void* sqlite3Codec(void *iCtx, void *data, Pgno pgno, int mode) {

codec_ctx *ctx = (codec_ctx *) iCtx;

int offset = 0, rc = 0;

int page_sz = sqlcipher_codec_ctx_get_pagesize(ctx);

unsigned char *pData = (unsigned char *) data;

void *buffer = sqlcipher_codec_ctx_get_data(ctx);

void *kdf_salt = sqlcipher_codec_ctx_get_kdf_salt(ctx);

CODEC_TRACE(("sqlite3Codec: entered pgno=%d, mode=%d, page_sz=%d\n", pgno, mode, page_sz));

/* call to derive keys if not present yet */

if((rc = sqlcipher_codec_key_derive(ctx)) != SQLITE_OK) {

sqlcipher_codec_ctx_set_error(ctx, rc);

return NULL;

}

if(pgno == 1) offset = FILE_HEADER_SZ; /* adjust starting pointers in data page for header offset on first page*/

CODEC_TRACE(("sqlite3Codec: switch mode=%d offset=%d\n", mode, offset));

switch(mode) {

case 0: /* decrypt */

case 2:

case 3:

if(pgno == 1) memcpy(buffer, SQLITE_FILE_HEADER, FILE_HEADER_SZ); /* copy file header to the first 16 bytes of the page */

rc = sqlcipher_page_cipher(ctx, CIPHER_READ_CTX, pgno, CIPHER_DECRYPT, page_sz - offset, pData + offset, (unsigned char*)buffer + offset);

if(rc != SQLITE_OK) sqlcipher_codec_ctx_set_error(ctx, rc);

memcpy(pData, buffer, page_sz); /* copy buffer data back to pData and return */

return pData;

break;

case 6: /* encrypt */

if(pgno == 1) memcpy(buffer, kdf_salt, FILE_HEADER_SZ); /* copy salt to output buffer */

rc = sqlcipher_page_cipher(ctx, CIPHER_WRITE_CTX, pgno, CIPHER_ENCRYPT, page_sz - offset, pData + offset, (unsigned char*)buffer + offset);

if(rc != SQLITE_OK) sqlcipher_codec_ctx_set_error(ctx, rc);

return buffer; /* return persistent buffer data, pData remains intact */

break;

case 7:

if(pgno == 1) memcpy(buffer, kdf_salt, FILE_HEADER_SZ); /* copy salt to output buffer */

rc = sqlcipher_page_cipher(ctx, CIPHER_READ_CTX, pgno, CIPHER_ENCRYPT, page_sz - offset, pData + offset, (unsigned char*)buffer + offset);

if(rc != SQLITE_OK) sqlcipher_codec_ctx_set_error(ctx, rc);

return buffer; /* return persistent buffer data, pData remains intact */

break;

default:

return pData;

break;

}

void sqlite3FreeCodecArg(void *pCodecArg) {

codec_ctx *ctx = (codec_ctx *) pCodecArg;

if(pCodecArg == NULL) return;

sqlcipher_codec_ctx_free(&ctx); // wipe and free allocated memory for the context

sqlcipher_deactivate(); /* cleanup related structures, OpenSSL etc, when codec is detatched */

}

int sqlite3CodecAttach(sqlite3* db, int nDb, const void *zKey, int nKey) {

struct Db *pDb = &db->aDb[nDb];

CODEC_TRACE(("sqlite3CodecAttach: entered nDb=%d zKey=%s, nKey=%d\n", nDb, (char *)zKey, nKey));

if(nKey && zKey && pDb->pBt) {

int rc;

Pager *pPager = pDb->pBt->pBt->pPager;

sqlite3_file *fd = sqlite3Pager_get_fd(pPager);

codec_ctx *ctx;

sqlcipher_activate(); /* perform internal initialization for sqlcipher */

sqlite3_mutex_enter(db->mutex);

/* point the internal codec argument against the contet to be prepared */

rc = sqlcipher_codec_ctx_init(&ctx, pDb, pDb->pBt->pBt->pPager, fd, zKey, nKey);

if(rc != SQLITE_OK) return rc; /* initialization failed, do not attach potentially corrupted context */

sqlite3pager_sqlite3PagerSetCodec(sqlite3BtreePager(pDb->pBt), sqlite3Codec, NULL, sqlite3FreeCodecArg, (void *) ctx);

codec_set_btree_to_codec_pagesize(db, pDb, ctx);

/* force secure delete. This has the benefit of wiping internal data when deleted

and also ensures that all pages are written to disk (i.e. not skipped by

sqlite3PagerDontWrite optimizations) */

sqlite3BtreeSecureDelete(pDb->pBt, 1);

/* if fd is null, then this is an in-memory database and

we dont' want to overwrite the AutoVacuum settings

if not null, then set to the default */

if(fd != NULL) {

sqlite3BtreeSetAutoVacuum(pDb->pBt, SQLITE_DEFAULT_AUTOVACUUM);

}

sqlite3_mutex_leave(db->mutex);

}

return SQLITE_OK;

}

void sqlite3_activate_see(const char* in) {

/* do nothing, security enhancements are always active */

}

static int sqlcipher_find_db_index(sqlite3 *db, const char *zDb) {

int db_index;

if(zDb == NULL){

return 0;

}

for(db_index = 0; db_index < db->nDb; db_index++) {

struct Db *pDb = &db->aDb[db_index];

if(strcmp(pDb->zName, zDb) == 0) {

return db_index;

}

return 0;

}

int sqlite3_key(sqlite3 *db, const void *pKey, int nKey) {

CODEC_TRACE(("sqlite3_key entered: db=%p pKey=%s nKey=%d\n", db, (char *)pKey, nKey));

return sqlite3_key_v2(db, "main", pKey, nKey);

}

int sqlite3_key_v2(sqlite3 *db, const char *zDb, const void *pKey, int nKey) {

CODEC_TRACE(("sqlite3_key_v2: entered db=%p zDb=%s pKey=%s nKey=%d\n", db, zDb, (char *)pKey, nKey));

/* attach key if db and pKey are not null and nKey is > 0 */

if(db && pKey && nKey) {

int db_index = sqlcipher_find_db_index(db, zDb);

return sqlite3CodecAttach(db, db_index, pKey, nKey);

}

return SQLITE_ERROR;

}

int sqlite3_rekey(sqlite3 *db, const void *pKey, int nKey) {

CODEC_TRACE(("sqlite3_rekey entered: db=%p pKey=%s nKey=%d\n", db, (char *)pKey, nKey));

return sqlite3_rekey_v2(db, "main", pKey, nKey);

}

/* sqlite3_rekey_v2

** Given a database, this will reencrypt the database using a new key.

** There is only one possible modes of operation - to encrypt a database

** that is already encrpyted. If the database is not already encrypted

** this should do nothing

** The proposed logic for this function follows:

** 1. Determine if the database is already encryptped

** 2. If there is NOT already a key present do nothing

** 3. If there is a key present, re-encrypt the database with the new key

int sqlite3_rekey_v2(sqlite3 *db, const char *zDb, const void *pKey, int nKey) {

CODEC_TRACE(("sqlite3_rekey_v2: entered db=%p zDb=%s pKey=%s, nKey=%d\n", db, zDb, (char *)pKey, nKey));

if(db && pKey && nKey) {

int db_index = sqlcipher_find_db_index(db, zDb);

struct Db *pDb = &db->aDb[db_index];

CODEC_TRACE(("sqlite3_rekey_v2: database pDb=%p db_index:%d\n", pDb, db_index));

if(pDb->pBt) {

codec_ctx *ctx;

int rc, page_count;

Pgno pgno;

PgHdr *page;

Pager *pPager = pDb->pBt->pBt->pPager;

sqlite3pager_get_codec(pDb->pBt->pBt->pPager, (void **) &ctx);

if(ctx == NULL) {

/* there was no codec attached to this database, so this should do nothing! */

CODEC_TRACE(("sqlite3_rekey_v2: no codec attached to db, exiting\n"));

return SQLITE_OK;

}

sqlite3_mutex_enter(db->mutex);

codec_set_pass_key(db, db_index, pKey, nKey, CIPHER_WRITE_CTX);

/* do stuff here to rewrite the database

** 1. Create a transaction on the database

** 2. Iterate through each page, reading it and then writing it.

** 3. If that goes ok then commit and put ctx->rekey into ctx->key

** note: don't deallocate rekey since it may be used in a subsequent iteration

rc = sqlite3BtreeBeginTrans(pDb->pBt, 1); /* begin write transaction */

sqlite3PagerPagecount(pPager, &page_count);

for(pgno = 1; rc == SQLITE_OK && pgno <= (unsigned int)page_count; pgno++) { /* pgno's start at 1 see pager.c:pagerAcquire */

if(!sqlite3pager_is_mj_pgno(pPager, pgno)) { /* skip this page (see pager.c:pagerAcquire for reasoning) */

rc = sqlite3PagerGet(pPager, pgno, &page);

if(rc == SQLITE_OK) { /* write page see pager_incr_changecounter for example */

rc = sqlite3PagerWrite(page);

if(rc == SQLITE_OK) {

sqlite3PagerUnref(page);

} else {

CODEC_TRACE(("sqlite3_rekey_v2: error %d occurred writing page %d\n", rc, pgno));

}

} else {

CODEC_TRACE(("sqlite3_rekey_v2: error %d occurred getting page %d\n", rc, pgno));

}

/* if commit was successful commit and copy the rekey data to current key, else rollback to release locks */

if(rc == SQLITE_OK) {

CODEC_TRACE(("sqlite3_rekey_v2: committing\n"));

rc = sqlite3BtreeCommit(pDb->pBt);

sqlcipher_codec_key_copy(ctx, CIPHER_WRITE_CTX);

} else {

CODEC_TRACE(("sqlite3_rekey_v2: rollback\n"));

sqlite3BtreeRollback(pDb->pBt, SQLITE_ABORT_ROLLBACK);

}

sqlite3_mutex_leave(db->mutex);

}

return SQLITE_OK;

}

return SQLITE_ERROR;

}

void sqlite3CodecGetKey(sqlite3* db, int nDb, void **zKey, int *nKey) {

struct Db *pDb = &db->aDb[nDb];

CODEC_TRACE(("sqlite3CodecGetKey: entered db=%p, nDb=%d\n", db, nDb));

if( pDb->pBt ) {

codec_ctx *ctx;

sqlite3pager_get_codec(pDb->pBt->pBt->pPager, (void **) &ctx);

if(ctx) { /* if the codec has an attached codec_context user the raw key data */

sqlcipher_codec_get_keyspec(ctx, zKey, nKey);

} else {

*zKey = NULL;

*nKey = 0;

}

#ifndef OMIT_EXPORT

* Implementation of an "export" function that allows a caller

* to duplicate the main database to an attached database. This is intended

* as a conveneince for users who need to:

* 1. migrate from an non-encrypted database to an encrypted database

* 2. move from an encrypted database to a non-encrypted database

* 3. convert beween the various flavors of encrypted databases.

* This implementation is based heavily on the procedure and code used

* in vacuum.c, but is exposed as a function that allows export to any

* named attached database.

** Finalize a prepared statement. If there was an error, store the

** text of the error message in *pzErrMsg. Return the result code.

** Based on vacuumFinalize from vacuum.c

static int sqlcipher_finalize(sqlite3 *db, sqlite3_stmt *pStmt, char **pzErrMsg){

int rc;

rc = sqlite3VdbeFinalize((Vdbe*)pStmt);

if( rc ){

sqlite3SetString(pzErrMsg, db, sqlite3_errmsg(db));

}

return rc;

}

** Execute zSql on database db. Return an error code.

** Based on execSql from vacuum.c

static int sqlcipher_execSql(sqlite3 *db, char **pzErrMsg, const char *zSql){

sqlite3_stmt *pStmt;

VVA_ONLY( int rc; )

if( !zSql ){

return SQLITE_NOMEM;

}

if( SQLITE_OK!=sqlite3_prepare(db, zSql, -1, &pStmt, 0) ){

sqlite3SetString(pzErrMsg, db, sqlite3_errmsg(db));

return sqlite3_errcode(db);

}

VVA_ONLY( rc = ) sqlite3_step(pStmt);

assert( rc!=SQLITE_ROW );

return sqlcipher_finalize(db, pStmt, pzErrMsg);

}

** Execute zSql on database db. The statement returns exactly

** one column. Execute this as SQL on the same database.

** Based on execExecSql from vacuum.c

static int sqlcipher_execExecSql(sqlite3 *db, char **pzErrMsg, const char *zSql){

sqlite3_stmt *pStmt;

int rc;

rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);

if( rc!=SQLITE_OK ) return rc;

while( SQLITE_ROW==sqlite3_step(pStmt) ){

rc = sqlcipher_execSql(db, pzErrMsg, (char*)sqlite3_column_text(pStmt, 0));

if( rc!=SQLITE_OK ){

sqlcipher_finalize(db, pStmt, pzErrMsg);

return rc;

}

return sqlcipher_finalize(db, pStmt, pzErrMsg);

}

* copy database and schema from the main database to an attached database

* Based on sqlite3RunVacuum from vacuum.c

void sqlcipher_exportFunc(sqlite3_context *context, int argc, sqlite3_value **argv) {

sqlite3 *db = sqlite3_context_db_handle(context);

const char* attachedDb = (const char*) sqlite3_value_text(argv[0]);

int saved_flags; /* Saved value of the db->flags */

int saved_nChange; /* Saved value of db->nChange */

int saved_nTotalChange; /* Saved value of db->nTotalChange */

void (*saved_xTrace)(void*,const char*); /* Saved db->xTrace */

int rc = SQLITE_OK; /* Return code from service routines */

char *zSql = NULL; /* SQL statements */

char *pzErrMsg = NULL;

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;

/* Query the schema of the main database. Create a mirror schema

** in the temporary database.

zSql = sqlite3_mprintf(

"SELECT 'CREATE TABLE %s.' || substr(sql,14) "

" FROM sqlite_master WHERE type='table' AND name!='sqlite_sequence'"

" AND rootpage>0"

, attachedDb);

rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql);

if( rc!=SQLITE_OK ) goto end_of_export;

sqlite3_free(zSql);

zSql = sqlite3_mprintf(

"SELECT 'CREATE INDEX %s.' || substr(sql,14)"

" FROM sqlite_master WHERE sql LIKE 'CREATE INDEX %%' "

, attachedDb);

rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql);

if( rc!=SQLITE_OK ) goto end_of_export;

sqlite3_free(zSql);

zSql = sqlite3_mprintf(

"SELECT 'CREATE UNIQUE INDEX %s.' || substr(sql,21) "

" FROM sqlite_master WHERE sql LIKE 'CREATE UNIQUE INDEX %%'"

, attachedDb);

rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql);

if( rc!=SQLITE_OK ) goto end_of_export;

sqlite3_free(zSql);

/* Loop through the tables in the main database. For each, do

** an "INSERT INTO rekey_db.xxx SELECT * FROM main.xxx;" to copy

** the contents to the temporary database.

zSql = sqlite3_mprintf(

"SELECT 'INSERT INTO %s.' || quote(name) "

"|| ' SELECT * FROM main.' || quote(name) || ';'"

"FROM main.sqlite_master "

"WHERE type = 'table' AND name!='sqlite_sequence' "

" AND rootpage>0"

, attachedDb);

rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql);

if( rc!=SQLITE_OK ) goto end_of_export;

sqlite3_free(zSql);

/* Copy over the sequence table

zSql = sqlite3_mprintf(

"SELECT 'DELETE FROM %s.' || quote(name) || ';' "

"FROM %s.sqlite_master WHERE name='sqlite_sequence' "

, attachedDb, attachedDb);

rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql);

if( rc!=SQLITE_OK ) goto end_of_export;

sqlite3_free(zSql);

zSql = sqlite3_mprintf(

"SELECT 'INSERT INTO %s.' || quote(name) "

"|| ' SELECT * FROM main.' || quote(name) || ';' "

"FROM %s.sqlite_master WHERE name=='sqlite_sequence';"

, attachedDb, attachedDb);

rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql);

if( rc!=SQLITE_OK ) goto end_of_export;

sqlite3_free(zSql);

/* Copy the triggers, views, and virtual tables from the main database

** over to the temporary database. None of these objects has any

** associated storage, so all we have to do is copy their entries

** from the SQLITE_MASTER table.

zSql = sqlite3_mprintf(

"INSERT INTO %s.sqlite_master "

" SELECT type, name, tbl_name, rootpage, sql"

" FROM main.sqlite_master"

" WHERE type='view' OR type='trigger'"

" OR (type='table' AND rootpage=0)"

, attachedDb);

rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execSql(db, &pzErrMsg, zSql);

if( rc!=SQLITE_OK ) goto end_of_export;

sqlite3_free(zSql);

zSql = NULL;

end_of_export:

db->flags = saved_flags;

db->nChange = saved_nChange;

db->nTotalChange = saved_nTotalChange;

db->xTrace = saved_xTrace;

sqlite3_free(zSql);

if(rc) {

if(pzErrMsg != NULL) {

sqlite3_result_error(context, pzErrMsg, -1);

sqlite3DbFree(db, pzErrMsg);

} else {

sqlite3_result_error(context, sqlite3ErrStr(rc), -1);

}

#endif

/* END SQLCIPHER */

#endif

sqlcipher/src/crypto.c at Xcode5 · securitykernel/sqlcipher · GitHub

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