Fix pgcrypto compilation with OpenSSL 1.1.0.

Was broken by the switch to using OpenSSL's EVP interface for ciphers, in
commit 5ff4a67.

Reported by Andres Freund. Fix by Michael Paquier with some kibitzing by me.

Discussion: https://www.postgresql.org/message-id/20161201014826.ic72tfkahmevpwz7@alap3.anarazel.de

Author: hlinnaka

contrib/pgcrypto/openssl.c

@@ -66,10 +66,10 @@ typedef struct OSSLDigest
 } OSSLDigest;
 
 static OSSLDigest *open_digests = NULL;
-static bool resowner_callback_registered = false;
+static bool digest_resowner_callback_registered = false;
 
 static void
-free_openssldigest(OSSLDigest *digest)
+free_openssl_digest(OSSLDigest *digest)
 {
 	EVP_MD_CTX_destroy(digest->ctx);
 	if (digest->prev)
@@ -106,7 +106,7 @@ digest_free_callback(ResourceReleasePhase phase,
 		{
 			if (isCommit)
 				elog(WARNING, "pgcrypto digest reference leak: digest %p still referenced", curr);
-			free_openssldigest(curr);
+			free_openssl_digest(curr);
 		}
 	}
 }
@@ -156,7 +156,7 @@ digest_free(PX_MD *h)
 {
 	OSSLDigest *digest = (OSSLDigest *) h->p.ptr;
 
-	free_openssldigest(digest);
+	free_openssl_digest(digest);
 	px_free(h);
 }
 
@@ -178,10 +178,10 @@ px_find_digest(const char *name, PX_MD **res)
 		OpenSSL_add_all_algorithms();
 	}
 
-	if (!resowner_callback_registered)
+	if (!digest_resowner_callback_registered)
 	{
 		RegisterResourceReleaseCallback(digest_free_callback, NULL);
-		resowner_callback_registered = true;
+		digest_resowner_callback_registered = true;
 	}
 
 	md = EVP_get_digestbyname(name);
@@ -240,6 +240,9 @@ px_find_digest(const char *name, PX_MD **res)
  */
 typedef const EVP_CIPHER *(*ossl_EVP_cipher_func)(void);
 
+/*
+ * ossl_cipher contains the static information about each cipher.
+ */
 struct ossl_cipher
 {
 	int			(*init) (PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv);
@@ -248,31 +251,89 @@ struct ossl_cipher
 	int			max_key_size;
 };
 
-typedef struct
+/*
+ * OSSLCipher contains the state for using a cipher. A separate OSSLCipher
+ * object is allocated in each px_find_cipher() call.
+ *
+ * To make sure we don't leak OpenSSL handles on abort, we keep OSSLCipher
+ * objects in a linked list, allocated in TopMemoryContext. We use the
+ * ResourceOwner mechanism to free them on abort.
+ */
+typedef struct OSSLCipher
 {
-	EVP_CIPHER_CTX	evp_ctx;
+	EVP_CIPHER_CTX *evp_ctx;
 	const EVP_CIPHER *evp_ciph;
 	uint8		key[MAX_KEY];
 	uint8		iv[MAX_IV];
 	unsigned	klen;
 	unsigned	init;
 	const struct ossl_cipher *ciph;
-} ossldata;
+
+	ResourceOwner owner;
+	struct OSSLCipher *next;
+	struct OSSLCipher *prev;
+} OSSLCipher;
+
+static OSSLCipher *open_ciphers = NULL;
+static bool cipher_resowner_callback_registered = false;
+
+static void
+free_openssl_cipher(OSSLCipher *od)
+{
+	EVP_CIPHER_CTX_free(od->evp_ctx);
+	if (od->prev)
+		od->prev->next = od->next;
+	else
+		open_ciphers = od->next;
+	if (od->next)
+		od->next->prev = od->prev;
+	pfree(od);
+}
+
+/*
+ * Close any open OpenSSL cipher handles on abort.
+ */
+static void
+cipher_free_callback(ResourceReleasePhase phase,
+					 bool isCommit,
+					 bool isTopLevel,
+					 void *arg)
+{
+	OSSLCipher *curr;
+	OSSLCipher *next;
+
+	if (phase != RESOURCE_RELEASE_AFTER_LOCKS)
+		return;
+
+	next = open_ciphers;
+	while (next)
+	{
+		curr = next;
+		next = curr->next;
+
+		if (curr->owner == CurrentResourceOwner)
+		{
+			if (isCommit)
+				elog(WARNING, "pgcrypto cipher reference leak: cipher %p still referenced", curr);
+			free_openssl_cipher(curr);
+		}
+	}
+}
 
 /* Common routines for all algorithms */
 
 static unsigned
 gen_ossl_block_size(PX_Cipher *c)
 {
-	ossldata   *od = (ossldata *) c->ptr;
+	OSSLCipher *od = (OSSLCipher *) c->ptr;
 
 	return od->ciph->block_size;
 }
 
 static unsigned
 gen_ossl_key_size(PX_Cipher *c)
 {
-	ossldata   *od = (ossldata *) c->ptr;
+	OSSLCipher *od = (OSSLCipher *) c->ptr;
 
 	return od->ciph->max_key_size;
 }
@@ -281,7 +342,7 @@ static unsigned
 gen_ossl_iv_size(PX_Cipher *c)
 {
 	unsigned	ivlen;
-	ossldata   *od = (ossldata *) c->ptr;
+	OSSLCipher *od = (OSSLCipher *) c->ptr;
 
 	ivlen = od->ciph->block_size;
 	return ivlen;
@@ -290,34 +351,31 @@ gen_ossl_iv_size(PX_Cipher *c)
 static void
 gen_ossl_free(PX_Cipher *c)
 {
-	ossldata   *od = (ossldata *) c->ptr;
+	OSSLCipher *od = (OSSLCipher *) c->ptr;
 
-	EVP_CIPHER_CTX_cleanup(&od->evp_ctx);
-	px_memset(od, 0, sizeof(*od));
-	px_free(od);
+	free_openssl_cipher(od);
 	px_free(c);
 }
 
 static int
 gen_ossl_decrypt(PX_Cipher *c, const uint8 *data, unsigned dlen,
 				 uint8 *res)
 {
-	ossldata   *od = c->ptr;
+	OSSLCipher *od = c->ptr;
 	int			outlen;
 
 	if (!od->init)
 	{
-		EVP_CIPHER_CTX_init(&od->evp_ctx);
-		if (!EVP_DecryptInit_ex(&od->evp_ctx, od->evp_ciph, NULL, NULL, NULL))
+		if (!EVP_DecryptInit_ex(od->evp_ctx, od->evp_ciph, NULL, NULL, NULL))
 			return PXE_CIPHER_INIT;
-		if (!EVP_CIPHER_CTX_set_key_length(&od->evp_ctx, od->klen))
+		if (!EVP_CIPHER_CTX_set_key_length(od->evp_ctx, od->klen))
 			return PXE_CIPHER_INIT;
-		if (!EVP_DecryptInit_ex(&od->evp_ctx, NULL, NULL, od->key, od->iv))
+		if (!EVP_DecryptInit_ex(od->evp_ctx, NULL, NULL, od->key, od->iv))
 			return PXE_CIPHER_INIT;
 		od->init = true;
 	}
 
-	if (!EVP_DecryptUpdate(&od->evp_ctx, res, &outlen, data, dlen))
+	if (!EVP_DecryptUpdate(od->evp_ctx, res, &outlen, data, dlen))
 		return PXE_DECRYPT_FAILED;
 
 	return 0;
@@ -327,22 +385,21 @@ static int
 gen_ossl_encrypt(PX_Cipher *c, const uint8 *data, unsigned dlen,
 				 uint8 *res)
 {
-	ossldata   *od = c->ptr;
+	OSSLCipher *od = c->ptr;
 	int			outlen;
 
 	if (!od->init)
 	{
-		EVP_CIPHER_CTX_init(&od->evp_ctx);
-		if (!EVP_EncryptInit_ex(&od->evp_ctx, od->evp_ciph, NULL, NULL, NULL))
+		if (!EVP_EncryptInit_ex(od->evp_ctx, od->evp_ciph, NULL, NULL, NULL))
 			return PXE_CIPHER_INIT;
-		if (!EVP_CIPHER_CTX_set_key_length(&od->evp_ctx, od->klen))
+		if (!EVP_CIPHER_CTX_set_key_length(od->evp_ctx, od->klen))
 			return PXE_CIPHER_INIT;
-		if (!EVP_EncryptInit_ex(&od->evp_ctx, NULL, NULL, od->key, od->iv))
+		if (!EVP_EncryptInit_ex(od->evp_ctx, NULL, NULL, od->key, od->iv))
 			return PXE_CIPHER_INIT;
 		od->init = true;
 	}
 
-	if (!EVP_EncryptUpdate(&od->evp_ctx, res, &outlen, data, dlen))
+	if (!EVP_EncryptUpdate(od->evp_ctx, res, &outlen, data, dlen))
 		return PXE_ERR_GENERIC;
 
 	return 0;
@@ -370,31 +427,38 @@ bf_check_supported_key_len(void)
 	static const uint8 data[8] = {0xfe, 0xdc, 0xba, 0x98, 0x76, 0x54, 0x32, 0x10};
 	static const uint8 res[8] = {0xc0, 0x45, 0x04, 0x01, 0x2e, 0x4e, 0x1f, 0x53};
 	uint8		out[8];
-	EVP_CIPHER_CTX	evp_ctx;
+	EVP_CIPHER_CTX *evp_ctx;
 	int			outlen;
+	int			status = 0;
 
 	/* encrypt with 448bits key and verify output */
-	EVP_CIPHER_CTX_init(&evp_ctx);
-	if (!EVP_EncryptInit_ex(&evp_ctx, EVP_bf_ecb(), NULL, NULL, NULL))
-		return 0;
-	if (!EVP_CIPHER_CTX_set_key_length(&evp_ctx, 56))
-		return 0;
-	if (!EVP_EncryptInit_ex(&evp_ctx, NULL, NULL, key, NULL))
+	evp_ctx = EVP_CIPHER_CTX_new();
+	if (!evp_ctx)
 		return 0;
+	if (!EVP_EncryptInit_ex(evp_ctx, EVP_bf_ecb(), NULL, NULL, NULL))
+		goto leave;
+	if (!EVP_CIPHER_CTX_set_key_length(evp_ctx, 56))
+		goto leave;
+	if (!EVP_EncryptInit_ex(evp_ctx, NULL, NULL, key, NULL))
+		goto leave;
 
-	if (!EVP_EncryptUpdate(&evp_ctx, out, &outlen, data, 8))
-		return 0;
+	if (!EVP_EncryptUpdate(evp_ctx, out, &outlen, data, 8))
+		goto leave;
 
 	if (memcmp(out, res, 8) != 0)
-		return 0;				/* Output does not match -> strong cipher is
+		goto leave;				/* Output does not match -> strong cipher is
 								 * not supported */
-	return 1;
+	status = 1;
+
+leave:
+	EVP_CIPHER_CTX_free(evp_ctx);
+	return status;
 }
 
 static int
 bf_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 {
-	ossldata   *od = c->ptr;
+	OSSLCipher *od = c->ptr;
 	unsigned	bs = gen_ossl_block_size(c);
 	static int	bf_is_strong = -1;
 
@@ -426,7 +490,7 @@ bf_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 static int
 ossl_des_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 {
-	ossldata   *od = c->ptr;
+	OSSLCipher *od = c->ptr;
 	unsigned	bs = gen_ossl_block_size(c);
 
 	od->klen = 8;
@@ -445,7 +509,7 @@ ossl_des_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 static int
 ossl_des3_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 {
-	ossldata   *od = c->ptr;
+	OSSLCipher *od = c->ptr;
 	unsigned	bs = gen_ossl_block_size(c);
 
 	od->klen = 24;
@@ -464,7 +528,7 @@ ossl_des3_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 static int
 ossl_cast_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 {
-	ossldata   *od = c->ptr;
+	OSSLCipher *od = c->ptr;
 	unsigned	bs = gen_ossl_block_size(c);
 
 	od->klen = klen;
@@ -482,7 +546,7 @@ ossl_cast_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 static int
 ossl_aes_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 {
-	ossldata   *od = c->ptr;
+	OSSLCipher *od = c->ptr;
 	unsigned	bs = gen_ossl_block_size(c);
 
 	if (klen <= 128 / 8)
@@ -507,7 +571,7 @@ ossl_aes_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 static int
 ossl_aes_ecb_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 {
-	ossldata   *od = c->ptr;
+	OSSLCipher *od = c->ptr;
 	int			err;
 
 	err = ossl_aes_init(c, key, klen, iv);
@@ -537,7 +601,7 @@ ossl_aes_ecb_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv
 static int
 ossl_aes_cbc_init(PX_Cipher *c, const uint8 *key, unsigned klen, const uint8 *iv)
 {
-	ossldata   *od = c->ptr;
+	OSSLCipher *od = c->ptr;
 	int			err;
 
 	err = ossl_aes_init(c, key, klen, iv);
@@ -683,7 +747,8 @@ px_find_cipher(const char *name, PX_Cipher **res)
 {
 	const struct ossl_cipher_lookup *i;
 	PX_Cipher  *c = NULL;
-	ossldata   *od;
+	EVP_CIPHER_CTX *ctx;
+	OSSLCipher *od;
 
 	name = px_resolve_alias(ossl_aliases, name);
 	for (i = ossl_cipher_types; i->name; i++)
@@ -692,13 +757,38 @@ px_find_cipher(const char *name, PX_Cipher **res)
 	if (i->name == NULL)
 		return PXE_NO_CIPHER;
 
-	od = px_alloc(sizeof(*od));
-	memset(od, 0, sizeof(*od));
+	if (!cipher_resowner_callback_registered)
+	{
+		RegisterResourceReleaseCallback(cipher_free_callback, NULL);
+		cipher_resowner_callback_registered = true;
+	}
+
+	/*
+	 * Create an OSSLCipher object, an EVP_CIPHER_CTX object and a PX_Cipher.
+	 * The order is crucial, to make sure we don't leak anything on
+	 * out-of-memory or other error.
+	 */
+	od = MemoryContextAllocZero(TopMemoryContext, sizeof(*od));
 	od->ciph = i->ciph;
 
+	/* Allocate an EVP_CIPHER_CTX object. */
+	ctx = EVP_CIPHER_CTX_new();
+	if (!ctx)
+	{
+		pfree(od);
+		return PXE_CIPHER_INIT;
+	}
+
+	od->evp_ctx = ctx;
+	od->owner = CurrentResourceOwner;
+	od->next = open_ciphers;
+	od->prev = NULL;
+	open_ciphers = od;
+
 	if (i->ciph->cipher_func)
 		od->evp_ciph = i->ciph->cipher_func();
 
+	/* The PX_Cipher is allocated in current memory context */
 	c = px_alloc(sizeof(*c));
 	c->block_size = gen_ossl_block_size;
 	c->key_size = gen_ossl_key_size;

contrib/pgcrypto/pgp-encrypt.c

@@ -219,6 +219,8 @@ encrypt_free(void *priv)
 {
 	struct EncStat *st = priv;
 
+	if (st->ciph)
+		pgp_cfb_free(st->ciph);
 	px_memset(st, 0, sizeof(*st));
 	px_free(st);
 }