integrity

问题 My web server generates a pdf, signs it, and give it to the client. The client sign it multiple times (with different tokens using Adobe Pro) and then upload it back to the server. I want the server to verify if it is the pdf that was previously generated by the server. I read that the hash is changed when multiple signatures are applied. How can do this verification easily with iText ? 回答1: Multiple integrated signatures in the same PDF are applied by means of incremental updates if done

问题 I found the same definition for referential and relational integrity. Are they the same? I have researched the two terms separately but cannot find any good definitions. 回答1: Yes, they are the same thing. The term "Referential Integrity" is used much more though. Referential Integrity relates to Foreign Keys in a Relational DB. For a table to exhibit Referential Integrity, the Foreign Key must either be null or reference an existing PK value in the related table. 来源： https://stackoverflow.com

问题 I'm writing a kernel module that checks the integrity of code segments for running tasks by controlling checksums. I ran into a few hurdles: How can I get the module_list variable if it isn't exported by the kernel (there is no such symbol in ksyms )? I can see all modules calling the lsmod command, so how can I get it in my module? While my module is running it shows that some code segments have been changed. It always happens with certain libraries. Why does it happen? I thought that code

问题 I'm using Laravel Eloquent's firstOrNew() function to retrieve a DB record based on 3 criteria: $summary = $this->firstOrNew(array( 'date' => $date, 'product_id' => $product_id, 'store_id' => $store_id, )); I also have a unique composite key of those 3 fields. Even though the record exists, the function doesn't retrieve it, so when I update an attribute and run $summary->save() I get the wonderful SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry >'2015-01-02-6-23' for key

问题 I have a model called UserProfile which stores additional data about a django user. This model has a OneToOneField to django.contrib.auth.models.User I also have a post save signal on a User object that is fired on initial insert of a User which creates a UserProfile object linked to that User: def create_user_profile(sender, instance, created, **kwargs): if created: UserProfile.objects.create(user=instance) post_save.connect(create_user_profile, sender=User) User objects can be created via

问题 HttpServletRequest 's getSession(boolean) method mentions session integrity. How does Tomcat maintains session integrity? What rules does it use? What method? What is happening under the hood precisely? EDIT How and when is a specific session ID is created? Does Tomcat rely on IP address and port for example? 回答1: In Tomcat the ManagerBase.generateSessionId() method is responsible for session id generation. It looks for me that session ids are generated based on random numbers. You can store

问题 In git, how do I verify that a merge upstream master commit does not contain any additional diffs? Say I want to verify that the person didn't do anything 'sneaky' besides actually merge the changes from the upstream master branch. I want to verify that the only diffs come from the other commits they made; that they did not perform an 'evil merge'. Is there a way to verify that no additional changes were made during the merge step? Or better yet: show me the potential 'evil merge' diffs so I

问题 I'm working on converting my backup script from shell to Python. One of the features of my old script was to check the created tarfile for integrity by doing: gzip -t . This seems to be a bit tricky in Python. It seems that the only way to do this, is by reading each of the compressed TarInfo objects within the tarfile. Is there a way to check a tarfile for integrity, without extracting to disk, or keeping it in memory (in it's entirety)? Good people on #python on freenode suggested that I

问题 This question is related to another existing SO question. HttpServletRequest's getSession(boolean) method mentions session integrity, but it does not define the concept. I could not find an offical definition. Is there any? Does anyone know what rules formally define when a session is in or out of integrity? Thanks. 回答1: It refers to the concept of linking the server session with the client (web browser) session with a cookie. I'm not sure how familiar you are with java web apps, but the

问题 I am able to achieve recursive file traversal in a directory (i.e to explore all the subdirectories and files in a directory). For that I have used an answer from a respective post on stack overflow. The snippet of that is below: var fs = require("fs"); var tree = function(dir, done) { var results = { "path": dir, "children": [] }; fs.readdir(dir, function(err, list) { if (err) { return done(err); } var pending = list.length; if (!pending) { return done(null, results); } list.forEach(function