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Merged
mtrojnar merged 1 commit into from
Apr 30, 2026
Merged

Simplify PKCS#11 C_Sign and C_Decrypt handling #654

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4 changes: 4 additions & 0 deletions src/libp11-int.h
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Original file line number Diff line number Diff line change
Expand Up @@ -389,6 +389,10 @@ extern int pkcs11_evp_pkey_rsa_sign(PKCS11_OBJECT_private *key, EVP_PKEY *pkey,
const unsigned char *tbs, size_t tbslen);

#ifndef OPENSSL_NO_EC
extern ECDSA_SIG *pkcs11_ec_sign_raw(PKCS11_OBJECT_private *key,
unsigned char *sig, size_t *siglen,
const unsigned char *tbs, size_t tbslen);

/* Sign digest input with EC private key via PKCS#11 and encode signature as DER */
extern int pkcs11_evp_pkey_ec_sign(PKCS11_OBJECT_private *key,
unsigned char *sig, size_t *siglen,
Expand Down
68 changes: 4 additions & 64 deletions src/p11_ec.c
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Expand Up @@ -415,44 +415,6 @@ static EVP_PKEY *pkcs11_get_evp_key_ec(PKCS11_OBJECT_private *key)

/********** ECDSA signing */

/* Signature size is the issue, will assume the caller has a big buffer! */
/* No padding or other stuff needed. We can call PKCS11 from here */
static int pkcs11_ecdsa_sign(const unsigned char *msg, unsigned int msg_len,
unsigned char *sigret, unsigned int *siglen, PKCS11_OBJECT_private *key)
{
int rv;
PKCS11_SLOT_private *slot = key->slot;
PKCS11_CTX_private *ctx = slot->ctx;
CK_SESSION_HANDLE session;
CK_MECHANISM mechanism;
CK_ULONG ck_sigsize;

ck_sigsize = *siglen;

memset(&mechanism, 0, sizeof(mechanism));
mechanism.mechanism = CKM_ECDSA;

if (pkcs11_get_session(slot, 0, &session))
return -1;

rv = CRYPTOKI_call(ctx,
C_SignInit(session, &mechanism, key->object));
if (!rv && key->always_authenticate == CK_TRUE)
rv = pkcs11_authenticate(key, session);
if (!rv)
rv = CRYPTOKI_call(ctx,
C_Sign(session, (CK_BYTE *)msg, msg_len, sigret, &ck_sigsize));
pkcs11_put_session(slot, session);

if (rv) {
CKRerr(CKR_F_PKCS11_ECDSA_SIGN, rv);
return -1;
}
*siglen = ck_sigsize;

return ck_sigsize;
}

#if OPENSSL_VERSION_NUMBER >= 0x10100000L && !defined(LIBRESSL_VERSION_NUMBER)

static void pkcs11_ec_finish(EC_KEY *ec)
Expand Down Expand Up @@ -483,14 +445,10 @@ static void pkcs11_ec_finish(EC_KEY *ec)
static ECDSA_SIG *pkcs11_ecdsa_sign_sig(const unsigned char *dgst, int dlen,
const BIGNUM *kinv, const BIGNUM *rp, EC_KEY *ec)
{
unsigned char sigret[512]; /* HACK for now */
ECDSA_SIG *sig;
unsigned char sigret[512]; /* existing temporary buffer size */
size_t siglen = sizeof sigret;
PKCS11_OBJECT_private *key;
unsigned int siglen;
BIGNUM *r, *s, *order;

(void)kinv; /* Precomputed values are not used for PKCS#11 */
(void)rp; /* Precomputed values are not used for PKCS#11 */
BIGNUM *order;

key = pkcs11_get_ex_data_ec(ec);
if (check_object_fork(key) < 0) {
Expand All @@ -517,25 +475,7 @@ static ECDSA_SIG *pkcs11_ecdsa_sign_sig(const unsigned char *dgst, int dlen,
}
BN_free(order);
}

siglen = sizeof sigret;
if (pkcs11_ecdsa_sign(dgst, dlen, sigret, &siglen, key) <= 0)
return NULL;

r = BN_bin2bn(sigret, siglen/2, NULL);
s = BN_bin2bn(sigret + siglen/2, siglen/2, NULL);
sig = ECDSA_SIG_new();
if (!sig)
return NULL;
#if OPENSSL_VERSION_NUMBER >= 0x10100000L || ( defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER >= 0x3050000fL )
ECDSA_SIG_set0(sig, r, s);
#else
BN_free(sig->r);
sig->r = r;
BN_free(sig->s);
sig->s = s;
#endif
return sig;
return pkcs11_ec_sign_raw(key, sigret, &siglen, dgst, dlen);
}

/********** ECDH key derivation */
Expand Down
77 changes: 26 additions & 51 deletions src/p11_eddsa.c
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Expand Up @@ -50,56 +50,20 @@ int (*orig_ed448_digestsign)(EVP_MD_CTX *ctx, unsigned char *sig, size_t *siglen

#if OPENSSL_VERSION_NUMBER < 0x40000000L

/* PKCS#11 sign implementation for Ed25519 / Ed448 */
static int pkcs11_eddsa_sign(unsigned char *sigret, unsigned int *siglen,
const unsigned char *tbs, unsigned int tbslen, PKCS11_OBJECT_private *key)
{
int rv;
PKCS11_SLOT_private *slot = key->slot;
PKCS11_CTX_private *ctx = slot->ctx;
CK_SESSION_HANDLE session;
CK_MECHANISM mechanism;
CK_ULONG ck_siglen = (CK_ULONG)(*siglen);
CK_ULONG ck_tbslen = (CK_ULONG)tbslen;

/* PureEdDSA, no prehash */
memset(&mechanism, 0, sizeof(mechanism));
mechanism.mechanism = CKM_EDDSA;

if (pkcs11_get_session(slot, 0, &session))
return -1;

rv = CRYPTOKI_call(ctx,
C_SignInit(session, &mechanism, key->object));
if (!rv && key->always_authenticate == CK_TRUE)
rv = pkcs11_authenticate(key, session);
if (!rv)
rv = CRYPTOKI_call(ctx,
C_Sign(session, (CK_BYTE_PTR)tbs, ck_tbslen, sigret, &ck_siglen));
pkcs11_put_session(slot, session);

if (rv) {
CKRerr(CKR_F_PKCS11_EDDSA_SIGN, rv);
return -1;
}
*siglen = (unsigned int)ck_siglen;
return (int)ck_siglen;
}

/*
* EVP_PKEY method sign wrapper for EdDSA.
* This function is invoked internally by EVP_PKEY_sign().
* If the key belongs to PKCS#11, perform signing via pkcs11_eddsa_sign().
* If the key belongs to PKCS#11, perform signing via pkcs11_evp_pkey_eddsa_sign().
*/
static int pkcs11_eddsa_pmeth_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
size_t *siglen, const unsigned char *tbs, size_t tbslen)
{
EVP_PKEY *pkey;
PKCS11_OBJECT_private *key;
int rv;
unsigned int tmp_len;
PKCS11_SLOT_private *slot;
CK_SESSION_HANDLE session;

if (*siglen > UINT_MAX)
if (siglen == NULL || *siglen > UINT_MAX)
return 0;

pkey = EVP_PKEY_CTX_get0_pkey(ctx);
Expand All @@ -110,12 +74,16 @@ static int pkcs11_eddsa_pmeth_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
if (!key)
return 0;

tmp_len = (unsigned int)*siglen;
rv = pkcs11_eddsa_sign(sig, &tmp_len, tbs, (unsigned int)tbslen, key);
if (rv < 0)
slot = key->slot;
if (!slot)
return 0;

if (pkcs11_get_session(slot, 0, &session))
return 0;

if (!pkcs11_evp_pkey_eddsa_sign(key, sig, siglen, tbs, tbslen))
return 0;

*siglen = tmp_len;
return 1;
}

Expand All @@ -126,16 +94,19 @@ static int pkcs11_eddsa_pmeth_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
* 1. Query the required signature length (sig == NULL).
* 2. Perform the actual signing when a buffer is provided (sig != NULL).
*
* If the key is managed by PKCS#11, the signing is performed via pkcs11_eddsa_sign().
* If the key is managed by PKCS#11, the signing is performed via pkcs11_evp_pkey_eddsa_sign().
* Otherwise, the call is delegated to the original OpenSSL Ed25519/Ed448 implementation.
*/
static int pkcs11_eddsa_pmeth_digestsign(EVP_MD_CTX *ctx, unsigned char *sig,
size_t *siglen, const unsigned char *tbs, size_t tbslen)
{
EVP_PKEY *pkey;
PKCS11_OBJECT_private *key;
unsigned int tmp_len;
int rv;
PKCS11_SLOT_private *slot;
CK_SESSION_HANDLE session;

if (siglen == NULL)
return -1;

pkey = EVP_PKEY_CTX_get0_pkey(EVP_MD_CTX_pkey_ctx(ctx));
if (!pkey)
Expand All @@ -145,6 +116,13 @@ static int pkcs11_eddsa_pmeth_digestsign(EVP_MD_CTX *ctx, unsigned char *sig,
if (!key)
return -1;

slot = key->slot;
if (!slot)
return -1;

if (pkcs11_get_session(slot, 0, &session))
return -1;

/* Step 1: caller asks for signature length only */
if (sig == NULL) {
if (EVP_PKEY_id(pkey) == EVP_PKEY_ED25519)
Expand All @@ -159,12 +137,9 @@ static int pkcs11_eddsa_pmeth_digestsign(EVP_MD_CTX *ctx, unsigned char *sig,
}

/* Step 2: actual signing */
tmp_len = (unsigned int)*siglen;
rv = pkcs11_eddsa_sign(sig, &tmp_len, tbs, (unsigned int)tbslen, key);
if (rv < 0)
if (!pkcs11_evp_pkey_eddsa_sign(key, sig, siglen, tbs, tbslen))
return -1;

*siglen = tmp_len;
return 1;
}

Expand Down
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