---
product: Chilkat
product_version: 11.7.0
language: c
language_label: C
class: CodeSign
license: bundle
platforms: windows
deprecated: false
reference_html: https://www.chilkatsoft.com/refdoc/c_CkCodeSignRef.html
---
# Chilkat CodeSign — C — v11.7.0

> Chilkat 11.7.0 · language=c · class=CodeSign · platforms=windows
> Other versions: replace `11.7.0` in this URL. Other languages: `https://www.chilkatsoft.com/ai-docs/v/11.7.0/<lang>/classes/CodeSign.md`.
> Language-wide rules (install, unlock, error model, strings/bytes): `https://www.chilkatsoft.com/ai-docs/v/11.7.0/c/guide.md`.

## Purpose

**Available only on: windows.** Do not use this class on other platforms.

**Sign, verify, inspect, and remove Authenticode signatures on Windows executables, installers, and scripts.**

`Chilkat.CodeSign` works directly with Authenticode signatures on Windows executable files such as `.exe` and `.dll`, and, starting in v11.7.0, on Windows Installer packages (`.msi`), PowerShell files (`.ps1`, `.psm1`, `.psd1`), and VBScript files (`.vbs`). It provides functionality for applying a code-signing signature, validating whether a signed executable can be trusted, extracting signature information, retrieving the signer certificate, and removing an existing signature.

**Sign executables, installers, and scripts**

Apply Authenticode signatures to EXE, DLL, MSI, PowerShell, and VBScript files using a certificate and associated private key.

**Validate trust**

Check whether a signed executable has a valid signature and whether the signing certificate chain can be trusted.

**Inspect signatures**

Extract details about the Authenticode signature, including signer information and signature-related metadata.

**Retrieve signer certificates**

Get the certificate used to sign the executable and inspect it with `Chilkat.Cert`.

**Remove signatures**

Remove an existing Authenticode signature from a signed file when an unsigned output file is required.

**Diagnostics**

Use detailed diagnostic output to troubleshoot signing, certificate, trust-chain, timestamping, or validation problems.

**Common pattern:** Load or provide a code-signing certificate that has access to its private key, sign the target file, optionally add timestamping if supported by the signing workflow, then verify the resulting signature and inspect diagnostics if validation does not succeed.

For an extended overview, see [CodeSign Class Overview](https://www.chilkatsoft.com/codesign_class_overview.asp).

## Object creation, unlocking and error handling

**Create/Dispose**

```c
HCkCodeSign instance = CkCodeSign_Create();
// ...
CkCodeSign_Dispose(instance);
```

`HCkCodeSign CkCodeSign_Create(void);`

Creates an instance of the HCkCodeSign object and returns a handle ("void \*" pointer). The handle is passed in the 1st argument for the functions listed on this page.

`void CkCodeSign_Dispose(HCkCodeSign handle);`

Objects created by calling CkCodeSign_Create must be freed by calling this method. A memory leak occurs if a handle is not disposed by calling this function. Also, any handle returned by a Chilkat "C" function must also be freed by the application by calling the appropriate Dispose method, such as CkCodeSign_Dispose.

Call `Global.UnlockBundle` once at the start of the program, before using this or any other Chilkat class. Any string unlocks a fully functional 30-day trial; a purchased unlock code is used in production. See `guide.md` for the exact code in C.

## Members common to every Chilkat class

Documented once per language in `common-members.md`; listed here so this page is self-contained.

| Property | Signature | Access | Meaning |
|---|---|---|---|
| `DebugLogFilePath` | `void CkCodeSign_getDebugLogFilePath(HCkCodeSign cHandle, HCkString retval); void CkCodeSign_putDebugLogFilePath(HCkCodeSign cHandle, const char *newVal); const char *CkCodeSign_debugLogFilePath(HCkCodeSign cHandle);` | read/write | If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. |
| `LastErrorHtml` | `void CkCodeSign_getLastErrorHtml(HCkCodeSign cHandle, HCkString retval); const char *CkCodeSign_lastErrorHtml(HCkCodeSign cHandle);` | read-only | Provides HTML-formatted information about the last called method or property. |
| `LastErrorText` | `void CkCodeSign_getLastErrorText(HCkCodeSign cHandle, HCkString retval); const char *CkCodeSign_lastErrorText(HCkCodeSign cHandle);` | read-only | Provides plain text information about the last called method or property. |
| `LastErrorXml` | `void CkCodeSign_getLastErrorXml(HCkCodeSign cHandle, HCkString retval); const char *CkCodeSign_lastErrorXml(HCkCodeSign cHandle);` | read-only | Provides XML-formatted information about the last called method or property. |
| `LastMethodSuccess` | `BOOL CkCodeSign_getLastMethodSuccess(HCkCodeSign cHandle); void CkCodeSign_putLastMethodSuccess(HCkCodeSign cHandle, BOOL newVal);` | read/write | Indicates the success or failure of the most recent method call: `TRUE` means success, `FALSE` means failure. |
| `Utf8` | `BOOL CkCodeSign_getUtf8(HCkCodeSign cHandle); void CkCodeSign_putUtf8(HCkCodeSign cHandle, BOOL newVal);` | read/write | When set to `TRUE`, all `const char *` arguments and return values are interpreted as UTF-8 strings. |
| `VerboseLogging` | `BOOL CkCodeSign_getVerboseLogging(HCkCodeSign cHandle); void CkCodeSign_putVerboseLogging(HCkCodeSign cHandle, BOOL newVal);` | read/write | If set to `TRUE`, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. |
| `Version` | `void CkCodeSign_getVersion(HCkCodeSign cHandle, HCkString retval); const char *CkCodeSign_version(HCkCodeSign cHandle);` | read-only | Version of the component/library, such as "10.1.0" |

## Member index

| Member | Kind | Signature |
|---|---|---|
| `HeartbeatMs` | property, read/write | `int CkCodeSign_getHeartbeatMs(HCkCodeSign cHandle); void CkCodeSign_putHeartbeatMs(HCkCodeSign cHandle, int newVal);` |
| `UncommonOptions` | property, read/write | `void CkCodeSign_getUncommonOptions(HCkCodeSign cHandle, HCkString retval); void CkCodeSign_putUncommonOptions(HCkCodeSign cHandle, const char *newVal); const char *CkCodeSign_uncommonOptions(HCkCodeSign cHandle);` |
| `AddSignature` | method | `BOOL CkCodeSign_AddSignature(HCkCodeSign cHandle, const char *path, HCkCert cert, HCkJsonObject options);` |
| `GetSignerCert` | method | `BOOL CkCodeSign_GetSignerCert(HCkCodeSign cHandle, HCkCert cert);` |
| `RemoveSignature` | method | `BOOL CkCodeSign_RemoveSignature(HCkCodeSign cHandle, const char *path);` |
| `VerifySignature` | method | `BOOL CkCodeSign_VerifySignature(HCkCodeSign cHandle, const char *path, HCkJsonObject sigInfo);` |

## Properties

### CodeSign.HeartbeatMs

`Chilkat 11.7.0 · c · CodeSign · HeartbeatMs · property · read/write · since 9.5.0.98`

```c
int CkCodeSign_getHeartbeatMs(HCkCodeSign cHandle);
void CkCodeSign_putHeartbeatMs(HCkCodeSign cHandle, int newVal);
```

**Full documentation for this property (same in every language):** [Event Callback Examples](https://www.chilkatsoft.com/ai-docs/v/11.7.0/articles/event_callback_examples.md)

Specifies the approximate interval, in milliseconds, between `AbortCheck` event callbacks during supported operations. An event handler can request that the current operation be aborted.

The default is `0`, which disables `AbortCheck` callbacks. Setting a positive value enables periodic callbacks when an operation is sufficiently long-running; methods that finish quickly may complete without generating one.

**Callback interval:** The interval is a scheduling target rather than a real-time guarantee. Callback timing can vary while waiting for private-key hardware, a timestamp authority, certificate-chain processing, or other operating-system services.

### CodeSign.UncommonOptions

`Chilkat 11.7.0 · c · CodeSign · UncommonOptions · property · read/write · since 9.5.0.97`

```c
void CkCodeSign_getUncommonOptions(HCkCodeSign cHandle, HCkString retval);
void CkCodeSign_putUncommonOptions(HCkCodeSign cHandle, const char *newVal);
const char *CkCodeSign_uncommonOptions(HCkCodeSign cHandle);
```

Provides a comma-separated list of specialized compatibility or validation options. The default is an empty string, which is appropriate for normal use.

| Option | Effect |
| :--- | :--- |
| `codesign-allow-expired-cert` | Prevents Authenticode verification from failing solely because the signing certificate is expired. |
| `codesign-allow-cert-padding` | Starting in v11.7.0. Prevents verification of an EXE or DLL from failing solely because the PE certificate table fails the strict check (extra data or entries outside the verified signature). The failed check is still reported in `LastErrorText`. Use only for files known to carry such data, such as some installers that store configuration data in the certificate table. |

**Use only for an explicit trust policy:** Each option relaxes only the one check it names; neither disables the file-integrity, signature, chain, or other validation checks. `codesign-allow-expired-cert` is not a substitute for timestamping. A signature carrying a valid trusted timestamp should ordinarily remain verifiable after the signing certificate expires without this option.

## Methods

### CodeSign.AddSignature

`Chilkat 11.7.0 · c · CodeSign · AddSignature · method · since 9.5.0.97`

```c
BOOL CkCodeSign_AddSignature(HCkCodeSign cHandle, const char *path, HCkCert cert, HCkJsonObject options);
```

Adds a Microsoft Authenticode signature to the file specified by `path`. The file is modified in place. `cert` supplies the code-signing certificate and must provide access to its associated private key. `options` supplies the signing configuration as JSON.

Starting in v11.7.0, Windows Installer packages, PowerShell files, and VBScript files can be signed in addition to Windows executables and DLLs. The supported file types are:

| File type | Extensions | Where the signature is stored |
| :--- | :--- | :--- |
| Windows PE images | `.exe`, `.dll`, and other PE files such as `.sys` and `.ocx` | The PE certificate table. PE files are identified from the file content, not the extension. |
| Windows Installer packages (starting in v11.7.0) | `.msi` | The package's digital signature stream. |
| PowerShell scripts, modules, and data files (starting in v11.7.0) | `.ps1`, `.psm1`, `.psd1` | A comment block appended to the file (`# SIG # Begin signature block` ... `# SIG # End signature block`). The file's text encoding (UTF-8, UTF-8 with BOM, or UTF-16) is kept. |
| VBScript files (starting in v11.7.0) | `.vbs` | A comment block appended to the file (`'' SIG '' Begin signature block` ... `'' SIG '' End signature block`). |

Any other file type (for example `.js`, `.cab`, or `.cat`) causes the method to return `FALSE`, with `LastErrorText` explaining that the file type is not supported, and the file is not modified. The file must already exist; this method does not create it.

Starting in v11.7.0, if the file is already Authenticode-signed, the existing signature is removed and replaced by the new one. (Before v11.7.0, signing an already-signed EXE or DLL added a second signature entry instead of replacing the first.)

**MSI packages and ECDSA certificates:** Windows does not accept an Authenticode signature on an MSI package when the signing certificate uses an ECDSA key. Windows signature checks, such as `signtool verify`, `Get-AuthenticodeSignature`, and the file's Digital Signatures properties, report the signature as invalid (`TRUST_E_BAD_DIGEST`, 0x80096010). This is a limitation of signed MSI files on Windows, not a Chilkat defect: an MSI signed by Microsoft's `signtool` with the same ECDSA certificate is rejected in the same way, and its signed content is identical to the signature Chilkat produces. Use an RSA code-signing certificate to sign MSI packages. ECDSA certificates work for EXE, DLL, PowerShell, and VBScript files.

Common `options` options include:

| JSON member | Purpose |
| :--- | :--- |
| `hashAlg` | Selects the file-digest algorithm, such as `sha256`. |
| `timestampToken.enabled` | Enables an RFC 3161 timestamp token. |
| `timestampToken.tsaUrl` | Specifies the timestamp authority URL. |
| `timestampToken.requestTsaCert` | Requests inclusion of the timestamp authority certificate. |
| `timestampToken.hashAlg` | Selects the timestamp-request digest algorithm, such as `sha256`. |

```
{
  "hashAlg": "sha256",
  "timestampToken": {
    "enabled": true,
    "tsaUrl": "http://timestamp.example.com",
    "requestTsaCert": true,
    "hashAlg": "sha256"
  }
}
```

**Timestamping is strongly recommended:** A trusted timestamp records that the signature existed while the code-signing certificate was valid. This normally allows the signature to continue validating after the signing certificate expires, provided the timestamp and certificate chains remain valid under the verifier's trust policy.

Returns TRUE for success, FALSE for failure.

Async variant: `AddSignatureAsync` — same arguments, returns a `Task` (see Async variants below).

### CodeSign.GetSignerCert

`Chilkat 11.7.0 · c · CodeSign · GetSignerCert · method · since 10.0.1`

```c
BOOL CkCodeSign_GetSignerCert(HCkCodeSign cHandle, HCkCert cert);
```

Retrieves the X.509 signer certificate discovered by the most recent call to `VerifySignature` on this `CodeSign` object. If the certificate is fully available, `cert` is loaded with it and the method returns `TRUE`. Otherwise, the method returns `FALSE`.

The returned object contains the public certificate only; it does not provide the signer's private key. Call this method after `VerifySignature` and use the same `CodeSign` instance.

Starting in v11.7.0, the signer certificate is available only after a call to `VerifySignature` that returned `TRUE`. After a failed verification, this method returns `FALSE`.

**Certificate retrieval versus trust:** Successfully retrieving the signer certificate does not independently validate the signature or establish trust. Use the result of `VerifySignature` and the returned signature information when making a trust decision.

Returns TRUE for success, FALSE for failure.

### CodeSign.RemoveSignature

`Chilkat 11.7.0 · c · CodeSign · RemoveSignature · method · since 9.5.0.97`

```c
BOOL CkCodeSign_RemoveSignature(HCkCodeSign cHandle, const char *path);
```

Removes the embedded Authenticode signature from the file specified by `path`: a Windows executable or DLL, or, starting in v11.7.0, a Windows Installer package (`.msi`), PowerShell file (`.ps1`, `.psm1`, `.psd1`), or VBScript file (`.vbs`). The file is modified in place. Returns `TRUE` if the signature is successfully removed; otherwise returns `FALSE`.

For PowerShell and VBScript files, the signature comment block is removed from the end of the file. For MSI packages, the digital signature stream and the extended signature stream (`MsiDigitalSignatureEx`) are removed.

**Effect of removal:** The resulting file is no longer Authenticode-signed and no longer carries the removed publisher and timestamp information. This operation does not delete the signing certificate from a Windows certificate store or alter the private key. Keep a backup when the original signed file must be retained.

Returns TRUE for success, FALSE for failure.

### CodeSign.VerifySignature

`Chilkat 11.7.0 · c · CodeSign · VerifySignature · method · since 9.5.0.97`

```c
BOOL CkCodeSign_VerifySignature(HCkCodeSign cHandle, const char *path, HCkJsonObject sigInfo);
```

Verifies the embedded Microsoft Authenticode signature of the file specified by `path`: a Windows executable or DLL, or, starting in v11.7.0, a Windows Installer package (`.msi`), PowerShell file (`.ps1`, `.psm1`, `.psd1`), or VBScript file (`.vbs`). See `AddSignature` for the supported file types. Other file types cause the method to return `FALSE`. Structured information about the signature, signer, certificate chain, digest algorithms, timestamp, and validation result is written to `sigInfo`.

Returns `TRUE` when the signature satisfies the applicable Authenticode validation checks under the current Windows trust configuration. This includes confirming that the signed portions of the file have not changed and evaluating the signing certificate and timestamp information, as applicable. An unsigned file or a signature that does not validate causes the method to return `FALSE`. Inspect `sigInfo` and `LastErrorText` for details.

Starting in v11.7.0, verification of an EXE or DLL also includes a strict check of the PE certificate table: it must hold exactly one signature entry, containing exactly the signature that was verified, with no extra data. Data in the certificate table is not covered by the Authenticode signature (see CVE-2013-3900), so anything hidden there would be unsigned. A file that fails this check causes the method to return `FALSE` unless the `codesign-allow-cert-padding` option is set in `UncommonOptions`.

MSI packages signed with an ECDSA certificate: this method can return `TRUE` for such a package, while Windows itself reports the signature as invalid. This is a limitation of signed MSI files on Windows, not a Chilkat defect; see the note in `AddSignature`.

**What successful verification means:** Authenticode verifies publisher identity, file integrity, and certificate trust according to the validation policy. It does not prove that the software is bug-free, safe to execute, or free of malicious behavior. Trust results can also depend on the Windows trusted-root store, certificate-chain availability, timestamp validity, revocation policy, and other system trust settings.

Returns TRUE for success, FALSE for failure.

## Events and callbacks

This binding delivers progress information through callbacks (AbortCheck, PercentDone, ProgressInfo, TaskCompleted) rather than events. See `guide.md` for how to attach them in C.

## Async variants

Each returns a `Task` instead of the result and takes the same arguments as the synchronous method; run the task, wait for `Finished`, then read the result from the task. No new Async methods are added from 11.7.0 on.

```c
HCkTask CkCodeSign_AddSignatureAsync(HCkCodeSign cHandle, const char *path, HCkCert cert, HCkJsonObject options);
```

## Related classes

[`Cert`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/c/classes/Cert.md), [`JsonObject`](https://www.chilkatsoft.com/ai-docs/v/11.7.0/c/classes/JsonObject.md)