rsa: Fix build with OpenSSL 1.1.x

The rsa_st struct has been made opaque in 1.1.x, add forward compatible
code to access the n, e, d members of rsa_struct.

EVP_MD_CTX_cleanup has been removed in 1.1.x and EVP_MD_CTX_reset should be
called to reinitialise an already created structure.

lib/rsa/rsa-sign.c

@@ -9,6 +9,7 @@
 #include <string.h>
 #include <image.h>
 #include <time.h>
+#include <openssl/bn.h>
 #include <openssl/rsa.h>
 #include <openssl/pem.h>
 #include <openssl/err.h>
@@ -20,6 +21,19 @@
 #define HAVE_ERR_REMOVE_THREAD_STATE
 #endif
 
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
+static void RSA_get0_key(const RSA *r,
+                 const BIGNUM **n, const BIGNUM **e, const BIGNUM **d)
+{
+   if (n != NULL)
+       *n = r->n;
+   if (e != NULL)
+       *e = r->e;
+   if (d != NULL)
+       *d = r->d;
+}
+#endif
+
 static int rsa_err(const char *msg)
 {
 	unsigned long sslErr = ERR_get_error();
@@ -286,16 +300,22 @@ static int rsa_init(void)
 {
 	int ret;
 
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
 	ret = SSL_library_init();
+#else
+	ret = OPENSSL_init_ssl(0, NULL);
+#endif
 	if (!ret) {
 		fprintf(stderr, "Failure to init SSL library\n");
 		return -1;
 	}
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
 	SSL_load_error_strings();
 
 	OpenSSL_add_all_algorithms();
 	OpenSSL_add_all_digests();
 	OpenSSL_add_all_ciphers();
+#endif
 
 	return 0;
 }
@@ -335,12 +355,15 @@ err_set_rsa:
 err_engine_init:
 	ENGINE_free(e);
 err_engine_by_id:
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
 	ENGINE_cleanup();
+#endif
 	return ret;
 }
 
 static void rsa_remove(void)
 {
+#if OPENSSL_VERSION_NUMBER < 0x10100000L
 	CRYPTO_cleanup_all_ex_data();
 	ERR_free_strings();
 #ifdef HAVE_ERR_REMOVE_THREAD_STATE
@@ -349,6 +372,7 @@ static void rsa_remove(void)
 	ERR_remove_state(0);
 #endif
 	EVP_cleanup();
+#endif
 }
 
 static void rsa_engine_remove(ENGINE *e)
@@ -409,7 +433,11 @@ static int rsa_sign_with_key(RSA *rsa, struct checksum_algo *checksum_algo,
 		ret = rsa_err("Could not obtain signature");
 		goto err_sign;
 	}
+	#if OPENSSL_VERSION_NUMBER < 0x10100000L
 		EVP_MD_CTX_cleanup(context);
+	#else
+		EVP_MD_CTX_reset(context);
+	#endif
 	EVP_MD_CTX_destroy(context);
 	EVP_PKEY_free(key);
 
@@ -479,6 +507,7 @@ static int rsa_get_exponent(RSA *key, uint64_t *e)
 {
 	int ret;
 	BIGNUM *bn_te;
+	const BIGNUM *key_e;
 	uint64_t te;
 
 	ret = -EINVAL;
@@ -487,17 +516,18 @@ static int rsa_get_exponent(RSA *key, uint64_t *e)
 	if (!e)
 		goto cleanup;
 
-	if (BN_num_bits(key->e) > 64)
+	RSA_get0_key(key, NULL, &key_e, NULL);
+	if (BN_num_bits(key_e) > 64)
 		goto cleanup;
 
-	*e = BN_get_word(key->e);
+	*e = BN_get_word(key_e);
 
-	if (BN_num_bits(key->e) < 33) {
+	if (BN_num_bits(key_e) < 33) {
 		ret = 0;
 		goto cleanup;
 	}
 
-	bn_te = BN_dup(key->e);
+	bn_te = BN_dup(key_e);
 	if (!bn_te)
 		goto cleanup;
 
@@ -527,6 +557,7 @@ int rsa_get_params(RSA *key, uint64_t *exponent, uint32_t *n0_invp,
 {
 	BIGNUM *big1, *big2, *big32, *big2_32;
 	BIGNUM *n, *r, *r_squared, *tmp;
+	const BIGNUM *key_n;
 	BN_CTX *bn_ctx = BN_CTX_new();
 	int ret = 0;
 
@@ -548,7 +579,8 @@ int rsa_get_params(RSA *key, uint64_t *exponent, uint32_t *n0_invp,
 	if (0 != rsa_get_exponent(key, exponent))
 		ret = -1;
 
-	if (!BN_copy(n, key->n) || !BN_set_word(big1, 1L) ||
+	RSA_get0_key(key, &key_n, NULL, NULL);
+	if (!BN_copy(n, key_n) || !BN_set_word(big1, 1L) ||
 	    !BN_set_word(big2, 2L) || !BN_set_word(big32, 32L))
 		ret = -1;