Finalise GCM and optionally verify a received authentication tag.

Synopsis

Declared in <openssl/modes.h>

int
CRYPTO_gcm128_finish(
    GCM128_CONTEXT* ctx,
    unsigned char const* tag,
    size_t len);

Return Value

1 on success (and tag match when verifying), or 0 on failure.

Parameters

Name

Description

ctx

GCM context after encrypt/decrypt (and AAD) processing.

tag

Expected tag to verify, or NULL to skip verification (encrypt path).

len

Length of tag in bytes when tag is non‐NULL.

Created with MrDocs