---
name: "nng_tls_engine_fips_mode"
section: "3tls"
platform: "linux"
package: "libnng-dev"
version: "1.10.1-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/nng_tls_engine_fips_mode"
---

# nng\_tls\_engine\_fips\_mode(3tls)

TLS FIPS 140-2 mode indicator

## NAME

nng\_tls\_engine\_fips\_mode - TLS FIPS 140-2 mode indicator

## SYNOPSIS

```
#include <nng/supplemental/tls/tls.h>
bool nng_tls_engine_fips_mode(void);
```

## DESCRIPTION

The `nng_tls_engine_fips_mode()` returns `true` if the TLS engine is operating in FIPS 140-2 mode, and `false` otherwise.

**Tip**\

FIPS 140-2 references a United States standard for the use of cryptography in information processing systems.

**Tip**\

The default TLS engine does not support FIPS 140-2 mode, and will always return false.  Alternative implementations with such support may be available from commercial suppliers.

**Note**\

Generally the FIPS 140-2 mode cannot be changed after program startup.

## RETURN VALUES

True if the TLS engine is in FIPS 140-2 mode, false otherwise.

## ERRORS

None.

## SEE ALSO

[nng\_tls\_engine(5)](/nng_tls_engine/5.md), [nng(7)](/nng/7.md)