> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/ios/get-started/samples/enctest.md). # Encryption Learn how to encrypt and decrypt PDF files in Apryse SDK. It includes samples to encrypt and decrypt PDFs using Obj-C Sample Obj-C code for using Apryse SDK to read encrypted (password protected) documents, secure a document with encryption, or remove encryption. Learn more about our [iOS SDK](/ios/guides.md). {% tabs %} {% tab title="Obj-C" %} {% code lineNumbers="true" %} ```objc //--------------------------------------------------------------------------------------- // Copyright (c) 2001-2024 by Apryse Software Inc. All Rights Reserved. // Consult legal.txt regarding legal and license information. //--------------------------------------------------------------------------------------- #import #import //--------------------------------------------------------------------------------------- // This sample shows encryption support in PDFNet. The sample reads an encrypted document and // sets a new SecurityHandler. The sample also illustrates how password protection can // be removed from an existing PDF document. //--------------------------------------------------------------------------------------- int main(int argc, char *argv[]) { @autoreleasepool { int ret = 0; [PTPDFNet Initialize: 0]; // Example 1: // secure a PDF document with password protection and adjust permissions @try { // Open the test file NSLog(@"Securing an existing document ..."); PTPDFDoc *doc = [[PTPDFDoc alloc] initWithFilepath: @"../../TestFiles/fish.pdf"]; [doc InitSecurityHandler]; // Perform some operation on the document. In this case we use low level SDF API // to replace the content stream of the first page with contents of file 'my_stream.txt' if (NO) // Optional { NSLog(@"Replacing the content stream, use Flate compression..."); // Get the page dictionary using the following path: trailer/Root/Pages/Kids/0 PTObj *page_dict = [[[[[[[[doc GetTrailer] Get: @"Root"] Value] Get: @"Pages"] Value ] Get: @"Kids"] Value] GetAt: 0]; // Embed a custom stream (file mystream.txt) using Flate compression. PTMappedFile *embed_file = [[PTMappedFile alloc] initWithFilename: @"../../TestFiles/mystream.txt"]; PTFilterReader *mystm = [[PTFilterReader alloc] initWithFilter: embed_file]; PTFlateEncode *encode = [[PTFlateEncode alloc] initWithInput_filter: [[PTFilter alloc] init] compression_level: -1 buf_sz: 256]; [page_dict Put: @"Contents" obj: [doc CreateIndirectStream: mystm filter_chain: encode]]; } //encrypt the document // Apply a new security handler with given security settings. // In order to open saved PDF you will need a user password 'test'. PTSecurityHandler *new_handler = [[PTSecurityHandler alloc] init]; // Set a new password required to open a document NSString* user_password=@"test"; [new_handler ChangeUserPassword: user_password]; // Set Permissions [new_handler SetPermission: e_ptprint value: YES]; [new_handler SetPermission: e_ptextract_content value: NO]; // Note: document takes the ownership of new_handler. [doc SetSecurityHandler: new_handler]; // Save the changes. NSLog(@"Saving modified file..."); [doc SaveToFile: @"../../TestFiles/Output/secured.pdf" flags: 0]; } @catch(NSException *e) { NSLog(@"%@", e.reason); ret = 1; } // Example 2: // Opens an encrypted PDF document and removes its security. @try { PTPDFDoc *doc = [[PTPDFDoc alloc] initWithFilepath: @"../../TestFiles/Output/secured.pdf"]; //If the document is encrypted prompt for the password if (![doc InitSecurityHandler]) { bool success=NO; NSLog(@"The password is: test"); int count; for(count=0; count<3;count++) { char input[255]; NSLog(@"A password required to open the document."); NSLog(@"Please enter the password:"); //scanf("%c", &input); NSString *password = @"test"; // int i = 0; // for (; i < 254; i++) { // if (input[i] == '\0') { // break; // } // [password stringByAppendingFormat: @"%c", input[i]]; // } if([doc InitStdSecurityHandler: password]) { success=true; NSLog(@"The password is correct."); break; } else if(count<3) { NSLog(@"The password is incorrect, please try again."); } } if(!success) { NSLog(@"Document authentication error...."); ret = 1; return ret; } PTSecurityHandler *hdlr = [doc GetSecurityHandler]; NSLog(@"Document Open Password: %d", [hdlr IsUserPasswordRequired]); NSLog(@"Permissions Password: %d", [hdlr IsMasterPasswordRequired]); NSLog(@"Permissions: "); NSLog(@" Has 'owner' permissions: %d", [hdlr GetPermission: e_ptowner]); NSLog(@" Open and decrypt the document: %d", [hdlr GetPermission: e_ptdoc_open]); NSLog(@" Allow content extraction: %d", [hdlr GetPermission: e_ptextract_content]); NSLog(@" Allow full document editing: %d", [hdlr GetPermission: e_ptdoc_modify]); NSLog(@" Allow printing: %d", [hdlr GetPermission: e_ptprint]); NSLog(@" Allow high resolution printing: %d", [hdlr GetPermission: e_ptprint_high]); NSLog(@" Allow annotation editing: %d", [hdlr GetPermission: e_ptmod_annot]); NSLog(@" Allow form fill: %d", [hdlr GetPermission: e_ptfill_forms]); NSLog(@" Allow content extraction for accessibility: %d", [hdlr GetPermission: e_ptaccess_support]); NSLog(@" Allow document assembly: %d", [hdlr GetPermission: e_ptassemble_doc]); } //remove all security on the document [doc RemoveSecurity]; [doc SaveToFile: @"../../TestFiles/Output/not_secured.pdf" flags: 0]; } @catch(NSException *e) { NSLog(@"%@", e.reason); ret = 1; } // Example 3: // Encrypt/Decrypt a PDF using PDFTron custom security handler @try { NSLog(@"-------------------------------------------------"); NSLog(@"Encrypt a document using PDFTron Custom Security handler with a custom id and password..."); PTPDFDoc *doc = [[PTPDFDoc alloc] initWithFilepath: @"../../TestFiles/BusinessCardTemplate.pdf"]; // Create PDFTron custom security handler with a custom id. Replace this with your own integer unsigned int custom_id = 123456789; PTSecurityHandler* custom_handler = [[PTPDFTronCustomSecurityHandler alloc] initWithCustom_id : custom_id]; // Add a password to the custom security handler NSString *pass = @"test"; [custom_handler ChangeUserPassword: pass]; [doc SetSecurityHandler: custom_handler]; // Save the changes. [doc SaveToFile: @"../../TestFiles/Output/BusinessCardTemplate_enc.pdf" flags: 0]; NSLog(@"Decrypt the PDFTron custom security encrypted document above..."); // Register the PDFTron Custom Security handler with the same custom id used in encryption [PTPDFNet AddPDFTronCustomHandler : custom_id]; PTPDFDoc *doc_enc = [[PTPDFDoc alloc] initWithFilepath: @"../../TestFiles/Output/BusinessCardTemplate_enc.pdf"]; [doc_enc InitStdSecurityHandler : pass]; [doc RemoveSecurity]; // Save the decrypted document [doc SaveToFile: @"../../TestFiles/Output/BusinessCardTemplate_enc_dec.pdf" flags: 0]; NSLog(@"Done. Result saved in BusinessCardTemplate_enc_dec.pdf"); } @catch(NSException *e) { NSLog(@"%@", e.reason); ret = 1; } [PTPDFNet Terminate: 0]; return ret; } } ``` {% endcode %} {% endtab %} {% tab title="Swift" %} {% code lineNumbers="true" %} ```swift //--------------------------------------------------------------------------------------- // Copyright (c) 2001-2019 by PDFTron Systems Inc. All Rights Reserved. // Consult legal.txt regarding legal and license information. //--------------------------------------------------------------------------------------- import PDFNet import Foundation //--------------------------------------------------------------------------------------- // This sample shows encryption support in PDFNet. The sample reads an encrypted document and // sets a new SecurityHandler. The sample also illustrates how password protection can // be removed from an existing PDF document. //--------------------------------------------------------------------------------------- func runEncTest() -> Int { return autoreleasepool { var ret: Int = 0 // Example 1: // secure a PDF document with password protection and adjust permissions do { try PTPDFNet.catchException { // Open the test file print("Securing an existing document ...") let doc: PTPDFDoc = PTPDFDoc(filepath: Bundle.main.path(forResource: "fish", ofType: "pdf")) doc.initSecurityHandler() // Perform some operation on the document. In this case we use low level SDF API // to replace the content stream of the first page with contents of file 'my_stream.txt' if false { // print("Replacing the content stream, use Flate compression...") // // // Get the page dictionary using the following path: trailer/Root/Pages/Kids/0 // let page_dict: PTObj = doc.getTrailer().get("Root").value().get("Pages").value().get("Kids").value().getAt(0) // // // Embed a custom stream (file mystream.txt) using Flate compression. // let embed_file = PTMappedFile(filename: Bundle.main.path(forResource: "my_stream", ofType: "txt")) // let mystm = PTFilterReader(filter: embed_file) // let encode = PTFlateEncode(input_filter: PTFilter(), compression_level: -1, buf_sz: 256) // page_dict.put("Contents", obj: doc.createIndirectStream(mystm, filter_chain: encode)) } //encrypt the document // Apply a new security handler with given security settings. // In order to open saved PDF you will need a user password 'test'. let new_handler: PTSecurityHandler = PTSecurityHandler() // Set a new password required to open a document let user_password = "test" new_handler.changeUserPassword(user_password) // Set Permissions new_handler.setPermission(e_ptprint, value: true) new_handler.setPermission(e_ptextract_content, value: false) // Note: document takes the ownership of new_handler. doc.setSecurityHandler(new_handler) // Save the changes. print("Saving modified file...") doc.save(toFile: URL(fileURLWithPath: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]).appendingPathComponent("secured.pdf").path, flags: 0) } } catch let e as NSError { print("Uncaught exception: \(e)") ret = 1 } // Example 2: // Opens an encrypted PDF document and removes its security. do { try PTPDFNet.catchException { let doc: PTPDFDoc = PTPDFDoc(filepath: URL(fileURLWithPath: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]).appendingPathComponent("secured.pdf").path) //If the document is encrypted prompt for the password if !doc.initSecurityHandler() { var success = false print("The password is: test") for count in 0..<3 { print("A password is required to open the document.") print("Please enter the password:") //let input = readLine() let password = "test" //for i in 0..<255 { // let value = input[input.index(input.startIndex, offsetBy: i)] // if value == "\0" { // break // } // password += ("\(value)") //} if doc.initStdSecurityHandler(password) { success = true print("The password is correct.") break } else if count < 3 { print("The password is incorrect, please try again.") } } if !success { print("Document authentication error....") ret = 1 return } let hdlr: PTSecurityHandler = doc.getSecurityHandler() print("Document Open Password: \(hdlr.isUserPasswordRequired())") print("Permissions Password: \(hdlr.isMasterPasswordRequired())") print("Permissions: ") print(" Has 'owner' permissions: \(hdlr.getPermission(e_ptowner))") print(" Open and decrypt the document: \(hdlr.getPermission(e_ptdoc_open))") print(" Allow content extraction: \(hdlr.getPermission(e_ptextract_content))") print(" Allow full document editing: \(hdlr.getPermission(e_ptdoc_modify))") print(" Allow printing: \(hdlr.getPermission(e_ptprint))") print(" Allow high resolution printing: \(hdlr.getPermission(e_ptprint_high))") print(" Allow annotation editing: \(hdlr.getPermission(e_ptmod_annot))") print(" Allow form fill: \(hdlr.getPermission(e_ptfill_forms))") print(" Allow content extraction for accessibility: \(hdlr.getPermission(e_ptaccess_support))") print(" Allow document assembly: \(hdlr.getPermission(e_ptassemble_doc))") } //remove all security on the document doc.removeSecurity() doc.save(toFile: URL(fileURLWithPath: NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true)[0]).appendingPathComponent("not_secured.pdf").path, flags: 0) } } catch let e as NSError { print("Uncaught exception: \(e)") ret = 1 } return ret } } ``` {% endcode %} {% endtab %} {% endtabs %} --- # Agent Instructions This documentation is published with GitBook. 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