From df13defd4fd4c5a7afff69bc9733e7526e07959a Mon Sep 17 00:00:00 2001 From: Richard Levitte Date: Thu, 27 Feb 2020 10:51:45 +0100 Subject: [PATCH] EVP: Check that key methods aren't foreign when exporting The EVP_PKEY_ASN1_METHOD function export_to() must check that the key we're trying to export has a known libcrypto method, i.e. is a built in RSA_METHOD, DSA_METHOD, etc. Otherwise, the method may be defined by the calling application, by an engine, by another library, and we simply cannot know all the quirks hidden behind that method, if we have access to the key data, or much anything. Such keys are simply deemed impossible to export to provider keys, i.e. have export_to() return 0. This cascades back to functions like evp_pkey_export_to_provider() and evp_pkey_upgrade_to_provider() and their callers. In most cases, this is fine, but if these get mixed in with provider side keys in any function, that function will fail. Fixes #11179 Fixes #9915 Reviewed-by: Tomas Mraz (Merged from https://github.com/openssl/openssl/pull/11193) --- crypto/dh/dh_ameth.c | 8 ++++++++ crypto/dsa/dsa_ameth.c | 7 +++++++ crypto/ec/ec_ameth.c | 7 +++++++ crypto/evp/m_sigver.c | 2 +- crypto/evp/pmeth_fn.c | 2 +- crypto/evp/signature.c | 2 +- crypto/rsa/rsa_ameth.c | 7 +++++++ 7 files changed, 32 insertions(+), 3 deletions(-) diff --git a/crypto/dh/dh_ameth.c b/crypto/dh/dh_ameth.c index 14c0842455..ecec5fbcf6 100644 --- a/crypto/dh/dh_ameth.c +++ b/crypto/dh/dh_ameth.c @@ -20,6 +20,7 @@ #include "dh_local.h" #include #include "crypto/asn1.h" +#include "crypto/dh.h" #include "crypto/evp.h" #include #include @@ -499,6 +500,13 @@ static int dh_pkey_export_to(const EVP_PKEY *from, void *to_keydata, OSSL_PARAM *params; int rv; + /* + * If the DH method is foreign, then we can't be sure of anything, and + * can therefore not export or pretend to export. + */ + if (dh_get_method(dh) != DH_OpenSSL()) + return 0; + if (p == NULL || g == NULL) return 0; diff --git a/crypto/dsa/dsa_ameth.c b/crypto/dsa/dsa_ameth.c index 9715a75d0d..94f3f43b8e 100644 --- a/crypto/dsa/dsa_ameth.c +++ b/crypto/dsa/dsa_ameth.c @@ -528,6 +528,13 @@ static int dsa_pkey_export_to(const EVP_PKEY *from, void *to_keydata, OSSL_PARAM *params; int rv; + /* + * If the DSA method is foreign, then we can't be sure of anything, and + * can therefore not export or pretend to export. + */ + if (DSA_get_method(dsa) != DSA_OpenSSL()) + return 0; + if (p == NULL || q == NULL || g == NULL) return 0; diff --git a/crypto/ec/ec_ameth.c b/crypto/ec/ec_ameth.c index d6807661ff..652086a93a 100644 --- a/crypto/ec/ec_ameth.c +++ b/crypto/ec/ec_ameth.c @@ -637,6 +637,13 @@ int ec_pkey_export_to(const EVP_PKEY *from, void *to_keydata, || (ecg = EC_KEY_get0_group(eckey)) == NULL) return 0; + /* + * If the EC_KEY method is foreign, then we can't be sure of anything, + * and can therefore not export or pretend to export. + */ + if (EC_KEY_get_method(eckey) != EC_KEY_OpenSSL()) + return 0; + ossl_param_bld_init(&tmpl); /* export the domain parameters */ diff --git a/crypto/evp/m_sigver.c b/crypto/evp/m_sigver.c index 225017b509..4b2cb4eb35 100644 --- a/crypto/evp/m_sigver.c +++ b/crypto/evp/m_sigver.c @@ -73,7 +73,7 @@ static int do_sigver_init(EVP_MD_CTX *ctx, EVP_PKEY_CTX **pctx, */ ERR_set_mark(); - if (locpctx->keytype == NULL) + if (locpctx->engine != NULL || locpctx->keytype == NULL) goto legacy; /* diff --git a/crypto/evp/pmeth_fn.c b/crypto/evp/pmeth_fn.c index ca0790fcd6..5d0e21ed68 100644 --- a/crypto/evp/pmeth_fn.c +++ b/crypto/evp/pmeth_fn.c @@ -38,7 +38,7 @@ static int evp_pkey_asym_cipher_init(EVP_PKEY_CTX *ctx, int operation) */ ERR_set_mark(); - if (ctx->keytype == NULL || ctx->engine != NULL) + if (ctx->engine != NULL || ctx->keytype == NULL) goto legacy; /* diff --git a/crypto/evp/signature.c b/crypto/evp/signature.c index c01f076609..acbe76592f 100644 --- a/crypto/evp/signature.c +++ b/crypto/evp/signature.c @@ -359,7 +359,7 @@ static int evp_pkey_signature_init(EVP_PKEY_CTX *ctx, int operation) */ ERR_set_mark(); - if (ctx->keytype == NULL) + if (ctx->engine != NULL || ctx->keytype == NULL) goto legacy; /* diff --git a/crypto/rsa/rsa_ameth.c b/crypto/rsa/rsa_ameth.c index f34eacf552..3411b734e5 100644 --- a/crypto/rsa/rsa_ameth.c +++ b/crypto/rsa/rsa_ameth.c @@ -1092,6 +1092,13 @@ static int rsa_pkey_export_to(const EVP_PKEY *from, void *to_keydata, OSSL_PARAM *params = NULL; int rv = 0; + /* + * If the RSA method is foreign, then we can't be sure of anything, and + * can therefore not export or pretend to export. + */ + if (RSA_get_method(rsa) != RSA_PKCS1_OpenSSL()) + return 0; + /* Public parameters must always be present */ if (n == NULL || e == NULL) goto err; -- 2.25.1