diff --git a/doc/management-notes.txt b/doc/management-notes.txt index 17645c1d..7e61ff50 100644 --- a/doc/management-notes.txt +++ b/doc/management-notes.txt @@ -832,7 +832,12 @@ END Base 64 encoded output of RSA_private_encrypt for RSA or ECDSA_sign() for EC using OpenSSL or mbedtls_pk_sign() using mbed TLS will provide a -correct signature. +correct signature. With the 'nopadding' argument to the +external-management-interface the interface expects unpadded signatures +(RSA_NO_PADDING in OpenSSL). When the 'nopadding' keyword is missing the +interfaces expects PKCS1 padded signatures for RSA keys (RSA_PKCS1_PADDING). +EC signatures are always unpadded. To support TLS 1.3 using unpadded +signatures is required. This capability is intended to allow the use of arbitrary cryptographic service providers with OpenVPN via the management interface. diff --git a/src/openvpn/manage.h b/src/openvpn/manage.h index d24abe09..4fe66abf 100644 --- a/src/openvpn/manage.h +++ b/src/openvpn/manage.h @@ -343,10 +343,11 @@ struct management *management_init(void); #endif #define MF_UNIX_SOCK (1<<8) #define MF_EXTERNAL_KEY (1<<9) -#define MF_UP_DOWN (1<<10) -#define MF_QUERY_REMOTE (1<<11) -#define MF_QUERY_PROXY (1<<12) -#define MF_EXTERNAL_CERT (1<<13) +#define MF_EXTERNAL_KEY_NOPADDING (1<<10) +#define MF_UP_DOWN (1<<11) +#define MF_QUERY_REMOTE (1<<12) +#define MF_QUERY_PROXY (1<<13) +#define MF_EXTERNAL_CERT (1<<14) bool management_open(struct management *man, const char *addr, diff --git a/src/openvpn/options.c b/src/openvpn/options.c index 111534a5..61762791 100644 --- a/src/openvpn/options.c +++ b/src/openvpn/options.c @@ -3025,6 +3025,35 @@ options_postprocess_verify(const struct options *o) } } +#if defined(ENABLE_CRYPTOAPI) || (defined(ENABLE_CRYPTO_OPENSSL) && defined(ENABLE_MANAGEMENT)) +static void +disable_tls13_if_avilable(struct options *o, const char* msg) +{ +#if OPENSSL_VERSION_NUMBER >= 0x10100000L + const int tls_version_max = + (o->ssl_flags >> SSLF_TLS_VERSION_MAX_SHIFT) & + SSLF_TLS_VERSION_MAX_MASK; + + /* + * The library we are *linked* against is OpenSSL 1.1.1 and therefore support TLS 1.3 + * this need to be a runtime version check since we can be compiled against 1.1.0 and + * then the library can be upgraded to 1.1.1 + */ + if (OpenSSL_version_num() >= 0x1010100fL && + (tls_version_max == TLS_VER_UNSPEC || tls_version_max > TLS_VER_1_2)) + { + msg(M_WARN, "%s Setting maximum TLS version to 1.2 ", msg); + o->ssl_flags &= ~(SSLF_TLS_VERSION_MAX_MASK << + SSLF_TLS_VERSION_MAX_SHIFT); + o->ssl_flags |= (TLS_VER_1_1 << SSLF_TLS_VERSION_MAX_SHIFT); + + } +#else + return; +#endif +} +#endif + static void options_postprocess_mutate(struct options *o) { @@ -3105,6 +3134,26 @@ options_postprocess_mutate(struct options *o) } #endif +#if defined(ENABLE_CRYPTO_MBEDTLS) && defined(MANAGMENT_EXTERNAL_KEY) + if (o->management_flags & MF_EXTERNAL_KEY_NOPADDING) + { + msg(M_FATAL, "mbed TLS does not support the 'nopadding' argument for the --management-external-key option"); + } +#endif + +#if defined(ENABLE_CRYPTOAPI) + if (o->cryptoapi_cert) + { + disable_tls13_if_avilable(o, "Warning: cryptapicert used."); + } +#endif +#if defined(ENABLE_CRYPTO_OPENSSL) && defined(ENABLE_MANAGEMENT) + if ((o->management_flags & MF_EXTERNAL_KEY) && !(o->management_flags & MF_EXTERNAL_KEY_NOPADDING)) + { + disable_tls13_if_avilable(o, "Warning: Using management-external-key " + "without nopadding option."); + } +#endif #if P2MP /* * Save certain parms before modifying options via --pull @@ -5178,9 +5227,13 @@ add_option(struct options *options, options->management_write_peer_info_file = p[1]; } #ifdef ENABLE_MANAGEMENT - else if (streq(p[0], "management-external-key") && !p[1]) + else if (streq(p[0], "management-external-key") && !p[2]) { VERIFY_PERMISSION(OPT_P_GENERAL); + if (p[1] && streq(p[1], "nopadding")) + { + options->management_flags |= MF_EXTERNAL_KEY_NOPADDING; + } options->management_flags |= MF_EXTERNAL_KEY; } else if (streq(p[0], "management-external-cert") && p[1] && !p[2]) @@ -8440,4 +8493,4 @@ add_option(struct options *options, } err: gc_free(&gc); -} \ No newline at end of file +} diff --git a/src/openvpn/ssl_openssl.c b/src/openvpn/ssl_openssl.c index 3f1f4658..30320453 100644 --- a/src/openvpn/ssl_openssl.c +++ b/src/openvpn/ssl_openssl.c @@ -1100,15 +1100,27 @@ openvpn_extkey_rsa_finish(RSA *rsa) */ static int get_sig_from_man(const unsigned char *dgst, unsigned int dgstlen, - unsigned char *sig, unsigned int siglen) + unsigned char *sig, unsigned int siglen, bool pkcs1pad) { char *in_b64 = NULL; char *out_b64 = NULL; int len = -1; + int bencret = -1; - /* convert 'dgst' to base64 */ - if (management - && openvpn_base64_encode(dgst, dgstlen, &in_b64) > 0) + if ((management->settings.flags & MF_EXTERNAL_KEY_NOPADDING) > 2 && pkcs1pad) + { + /* + * Add PKCS1 signature and replace input with it + * Use our output buffer also als temporary buffer + */ + RSA_padding_add_PKCS1_type_1(sig, siglen, dgst, dgstlen); + bencret = openvpn_base64_encode(sig, siglen, &in_b64); + } + else + { + bencret = openvpn_base64_encode(dgst, dgstlen, &in_b64); + } + if (management && bencret > 0) { out_b64 = management_query_pk_sig(management, in_b64); } @@ -1129,13 +1141,13 @@ rsa_priv_enc(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, i unsigned int len = RSA_size(rsa); int ret = -1; - if (padding != RSA_PKCS1_PADDING) + if (padding != RSA_PKCS1_PADDING && padding != RSA_NO_PADDING) { RSAerr(RSA_F_RSA_OSSL_PRIVATE_ENCRYPT, RSA_R_UNKNOWN_PADDING_TYPE); return -1; } - ret = get_sig_from_man(from, flen, to, len); + ret = get_sig_from_man(from, flen, to, len, padding == RSA_PKCS1_PADDING); return (ret == len)? ret : -1; } @@ -1229,7 +1241,7 @@ ecdsa_sign(int type, const unsigned char *dgst, int dgstlen, unsigned char *sig, unsigned int *siglen, const BIGNUM *kinv, const BIGNUM *r, EC_KEY *ec) { int capacity = ECDSA_size(ec); - int len = get_sig_from_man(dgst, dgstlen, sig, capacity); + int len = get_sig_from_man(dgst, dgstlen, sig, capacity, false); if (len > 0) {