c - 在 PostgreSQL 中准备、存储、检索加密数据

Question

有谁知道如何正确准备将 BYTEA 数据类型插入到 postgresql 中？我有一个从 libmcrypt 生成的加密字符串。我希望将加密存储在定义为的表列中 “cdata bytea 不为空”

我的核心可以与命令行完美配合，但现在我希望将加密存储在 RDBMS 中，而不是文件。代码片段如下:

int rs;
char buffer[1];
char dbuffer[1024];
datafile = "This is my house";  // assume this to be a file
crypt_key[] = "12345678901234567890123456789012";  //  32 bytes
crypt_iv[] =  "11111111111111111111111111111111";  // 32 bytes
mfd = mcrypt_module_open(MCRYPT_RIJNDAEL_256, NULL, "cfb", NULL);  // assume success
mcrypt_generic_init(mfd, crypt_Key, 32,crypt_iv);  // assume success

while(readInputFile(datafile,buffer,sizeof(buffer),&bytes) == cgiFormSuccess) {
        mcrypt_generic(mfd,buffer,sizeof(buffer));  // buffer size s/b 1
        dbuffer[i++] = *buffer;
        dbuffer[i] = '\0';  // Time spent on string sanity
}  // processed each byte is now encrypted

// Now I wish to prepare dbuffer for table insertion
sb = PQescapeByteaConn(dbconn,dbuffer,(size_t)strlen(dbuffer),&rs);

// Perform Insertion --> cdata::BYTEA
sprintf(query,"INSERT INTO crypto (uid,crypt_key,crypt_iv,cdata,cfile)"
                  "VALUES('%s','%s','%s','%s','%s')",
         ebs->uid,ebs->crkey,ebs->crivs,sb,credf);  // cfile == original filename
ebs->r=db_func_query(ebs->r,query,0,proc);  // Please assume DB command success

// Expected output sb == \x...some hex, dbuffer == encrypted bytes.  sb is now in bytea table column.
######################################
// Prepare to decrypt the cdata::bytea column

sprintf(query,"DECLARE %s CURSOR FOR SELECT crypt_iv,cdata,cfile "  // not sure if cursor s/b regular or binary for this
                  "FROM crypto WHERE uid='%s' AND crypt_iv='%s' AND action=true",
         VCURSOR,ebs->uid,ebs->crkey);

db_func_txn_begin(ebs->r,proc);
ebs->r = db_func_query(ebs->r,query,1,proc);  // process the query and assume it delivers the row
if(totalrow) {
     nFields = PQnfields(ebs->r);
     char* results[nFields];
     for(i = 0;i < totalrow;i++) {
          for(j = 0;j < nFields;j++)
               results[j] = PQgetvalue(ebs->r,i,j);
          strcpy(crypt_iv,results[0]);
          strcpy(dbuffer,results[1]);
          strcpy(cfile,results[2]);
}
mcrypt_generic_init(mfd, crypt_Key, 32,crypt_iv);  // assume success
sb = PQunescapeBytea(dataBuf,&rs);

for(i = 0;i < rs+1;i++) {
     mdecrypt_generic(mfd,sb[i],1);  // buffer size s/b 1
     dbuffer[i] = sb[i];
     dbuffer[i+1] = '\0';  // Time spent on string sanity
}

// Expected output sb == reverse of PQescapeByteaConn, dbuffer == unencrypted bytes.

必须有一种方法可以成功插入和查询加密字符串以进行解密。

提前致谢。

Answer 1

问题已解决。只要转义 mcrypted 字符串的输出，您就可以只使用文本列。 Bytea 更干净，但代码行更多，PGunescapeBytea 显然是强制解密的。