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C

PDF Get Encryption and Permissions Information

See more PDF Signatures Examples

Determine if a PDF is encrypted, and the associated user permissions.

Note: Some PDFs are encrypted but not password-protected. In such cases, encryption is used primarily for preventing unauthorized modifications to the document, but it doesn't restrict access. Therefore, you can open and read the document without a password.

Chilkat C Downloads

C
#include <C_CkPdf.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkPdf pdf;
    HCkJsonObject ljd;
    const char *pdfVersion;
    const char *Filter;
    int KeyLength;
    int V;
    int R;
    int P;
    const char *PrintLowResolution;
    const char *PrintHighResolution;
    const char *ModifyOther;
    const char *ModifyAnnotations;
    const char *ModifyForms;
    const char *FillInForms;
    const char *AssembleDoc;
    const char *ExtractAnyPurpose;
    const char *ExtractAccessibility;
    const char *Method;

    success = FALSE;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    pdf = CkPdf_Create();

    // Load a PDF.
    success = CkPdf_LoadFile(pdf,"c:/someDir/sample.pdf");
    if (success == FALSE) {
        printf("%s\n",CkPdf_lastErrorText(pdf));
        CkPdf_Dispose(pdf);
        return;
    }

    // Get information about the PDF that was collected in the call to LoadFile.
    ljd = CkJsonObject_Create();
    CkPdf_GetLastJsonData(pdf,ljd);

    CkJsonObject_putEmitCompact(ljd,FALSE);

    printf("%s\n",CkJsonObject_emit(ljd));

    // Sample output:

    // {
    //   "pdfVersion": "1.6",
    //   "encrypt": {
    //     "filter": "/Standard",
    //     "keyLength": 128,
    //     "V": 4,
    //     "R": 4,
    //     "P": -1340,
    //     "perm": {
    //       "printLowResolution": "allowed",
    //       "printHighResolution": "allowed",
    //       "modifyOther": "not allowed",
    //       "modifyAnnotations": "allowed",
    //       "modifyForms": "not allowed",
    //       "fillInForms": "allowed",
    //       "assembleDoc": "allowed",
    //       "extractAnyPurpose": "not allowed",
    //       "extractAccessibility": "not allowed"
    //     },
    //     "method": "AESV2"
    //   }
    // }

    // Use this online tool to generate parsing code from sample JSON: 
    // Generate Parsing Code from JSON

    // Chilkat functions returning "const char *" return a pointer to temporary internal memory owned and managed by Chilkat.
    // See this example explaining how this memory should be used: const char * functions.

    pdfVersion = CkJsonObject_stringOf(ljd,"pdfVersion");
    Filter = CkJsonObject_stringOf(ljd,"encrypt.filter");
    KeyLength = CkJsonObject_IntOf(ljd,"encrypt.keyLength");
    V = CkJsonObject_IntOf(ljd,"encrypt.V");
    R = CkJsonObject_IntOf(ljd,"encrypt.R");
    P = CkJsonObject_IntOf(ljd,"encrypt.P");
    PrintLowResolution = CkJsonObject_stringOf(ljd,"encrypt.perm.printLowResolution");
    PrintHighResolution = CkJsonObject_stringOf(ljd,"encrypt.perm.printHighResolution");
    ModifyOther = CkJsonObject_stringOf(ljd,"encrypt.perm.modifyOther");
    ModifyAnnotations = CkJsonObject_stringOf(ljd,"encrypt.perm.modifyAnnotations");
    ModifyForms = CkJsonObject_stringOf(ljd,"encrypt.perm.modifyForms");
    FillInForms = CkJsonObject_stringOf(ljd,"encrypt.perm.fillInForms");
    AssembleDoc = CkJsonObject_stringOf(ljd,"encrypt.perm.assembleDoc");
    ExtractAnyPurpose = CkJsonObject_stringOf(ljd,"encrypt.perm.extractAnyPurpose");
    ExtractAccessibility = CkJsonObject_stringOf(ljd,"encrypt.perm.extractAccessibility");
    Method = CkJsonObject_stringOf(ljd,"encrypt.method");


    CkPdf_Dispose(pdf);
    CkJsonObject_Dispose(ljd);

    }