ASN1_ITEM_VERIFY(3)        Library Functions Manual        ASN1_ITEM_VERIFY(3)

NAME
     ASN1_item_verify - signature verification for ASN.1 values

SYNOPSIS
     #include <openssl/x509.h>

     int
     ASN1_item_verify(const ASN1_ITEM *it, X509_ALGOR *algor1,
         ASN1_BIT_STRING *sig_in, void *val_in, EVP_PKEY *pkey);

DESCRIPTION
     ASN1_item_verify() assumes that val_in is an ASN1_VALUE of the type
     specified by it, encodes it into DER format by calling ASN1_item_i2d(3),
     and verifies in a way similar to EVP_DigestVerify(3) that sig_in contains
     a valid signature of the resulting byte array, a signature that was
     created with the signature algorithm algor1 and the private key
     corresponding to the public key pkey.

RETURN VALUES
     ASN1_item_verify() returns 1 if signature verification succeeds, 0 if
     signature verification fails, or -1 if pkey is NULL, if sig_in contains
     invalid flags, or if algor1 requests an invalid or unsupported digest
     algorithm or does not work with the given pkey.

SEE ALSO
     ASN1_BIT_STRING_new(3), ASN1_item_i2d(3), ASN1_item_sign(3),
     EVP_DigestVerify(3), EVP_PKEY_new(3), OBJ_find_sigid_algs(3),
     X509_ALGOR_new(3)

HISTORY
     ASN1_item_verify() first appeared in OpenSSL 0.9.7 and has been available
     since OpenBSD 3.1.

Linux 6.8.2-arch2-1            December 18, 2021           Linux 6.8.2-arch2-1