5 EVP_PKEY_verify_init, EVP_PKEY_verify - signature verification using a public key algorithm
9 #include <openssl/evp.h>
11 int EVP_PKEY_verify_init(EVP_PKEY_CTX *ctx);
12 int EVP_PKEY_verify(EVP_PKEY_CTX *ctx,
13 const unsigned char *sig, size_t siglen,
14 const unsigned char *tbs, size_t tbslen);
18 The EVP_PKEY_verify_init() function initializes a public key algorithm
19 context using key B<pkey> for a signature verification operation.
21 The EVP_PKEY_verify() function performs a public key verification operation
22 using B<ctx>. The signature is specified using the B<sig> and
23 B<siglen> parameters. The verified data (i.e. the data believed originally
24 signed) is specified using the B<tbs> and B<tbslen> parameters.
28 After the call to EVP_PKEY_verify_init() algorithm specific control
29 operations can be performed to set any appropriate parameters for the
32 The function EVP_PKEY_verify() can be called more than once on the same
33 context if several operations are performed using the same parameters.
37 EVP_PKEY_verify_init() and EVP_PKEY_verify() return 1 if the verification
38 was successful and 0 if it failed. Unlike other functions the return value
39 0 only indicates that the signature did not not verify successfully (that is
40 tbs did not match the original data or the signature was of invalid form)
41 it is not an indication of a more serious error.
43 A negative value indicates an error other that signature verification failure.
44 In particular a return value of -2 indicates the operation is not supported by
45 the public key algorithm.
49 Verify signature using PKCS#1 and SHA256 digest:
55 L<EVP_PKEY_CTX_new(3)|EVP_PKEY_CTX_new(3)>,
56 L<EVP_PKEY_encrypt(3)|EVP_PKEY_encrypt(3)>,
57 L<EVP_PKEY_decrypt(3)|EVP_PKEY_decrypt(3)>,
58 L<EVP_PKEY_sign(3)|EVP_PKEY_sign(3)>,
59 L<EVP_PKEY_verifyrecover(3)|EVP_PKEY_verifyrecover(3)>,
60 L<EVP_PKEY_derive(3)|EVP_PKEY_derive(3)>
64 These functions were first added to OpenSSL 0.9.9.