From: Andre Noll <maan@tuebingen.mpg.de>
Date: Sun, 10 Jul 2016 20:23:45 +0000 (+0200)
Subject: crypto: Simplify asymetric key handling.
X-Git-Tag: v0.6.0~14^2~3
X-Git-Url: https://git.tuebingen.mpg.de/?a=commitdiff_plain;h=f553ab861efaa14f3a07ffb074c9e640b9fc776a;p=paraslash.git
crypto: Simplify asymetric key handling.
get_asymmetric_key() and free_asymmetric_key() are public because
para_server maintains a copy to the public key of each user so that
the keys need to be loaded only once. On the other hand, for private
keys (used in para_client) key allocation and freeing is performed
implicitly in priv_decrypt(), and no reference to the key is ever
returned. So the crypto API can be simplified by exposing the interface
only for public keys.
Hence this patch renames get_asymmetric_key() to get_public_key()
and drops the "private" argument. Similarly, free_asymmetric_key()
is renamed to free_public_key().
---
diff --git a/crypt.c b/crypt.c
index 085c0563..c15768a3 100644
--- a/crypt.c
+++ b/crypt.c
@@ -155,8 +155,7 @@ fail:
return ret;
}
-int get_asymmetric_key(const char *key_file, int private,
- struct asymmetric_key **result)
+int get_public_key(const char *key_file, struct asymmetric_key **result)
{
struct asymmetric_key *key = NULL;
void *map = NULL;
@@ -166,10 +165,6 @@ int get_asymmetric_key(const char *key_file, int private,
char *cp;
key = para_malloc(sizeof(*key));
- if (private) {
- ret = get_openssl_key(key_file, &key->rsa, LOAD_PRIVATE_KEY);
- goto out;
- }
ret = mmap_full_file(key_file, O_RDONLY, &map, &map_size, NULL);
if (ret < 0)
goto out;
@@ -210,7 +205,7 @@ out:
return ret;
}
-void free_asymmetric_key(struct asymmetric_key *key)
+void free_public_key(struct asymmetric_key *key)
{
if (!key)
return;
@@ -229,9 +224,12 @@ int priv_decrypt(const char *key_file, unsigned char *outbuf,
return ret;
if (inlen < 0)
return -E_RSA;
- ret = get_asymmetric_key(key_file, LOAD_PRIVATE_KEY, &priv);
- if (ret < 0)
+ priv = para_malloc(sizeof(*priv));
+ ret = get_openssl_key(key_file, &priv->rsa, LOAD_PRIVATE_KEY);
+ if (ret < 0) {
+ free(priv);
return ret;
+ }
/*
* RSA is vulnerable to timing attacks. Generate a random blinding
* factor to protect against this kind of attack.
@@ -245,7 +243,8 @@ int priv_decrypt(const char *key_file, unsigned char *outbuf,
if (ret <= 0)
ret = -E_DECRYPT;
out:
- free_asymmetric_key(priv);
+ RSA_free(priv->rsa);
+ free(priv);
return ret;
}
diff --git a/crypt.h b/crypt.h
index 9be7a23e..6f3befdb 100644
--- a/crypt.h
+++ b/crypt.h
@@ -51,22 +51,21 @@ int priv_decrypt(const char *key_file, unsigned char *outbuf,
* Read an asymmetric key from a file.
*
* \param key_file The file containing the key.
- * \param private if non-zero, read the private key, otherwise the public key.
* \param result The key structure is returned here.
*
* \return The size of the key on success, negative on errors.
*/
-int get_asymmetric_key(const char *key_file, int private,
- struct asymmetric_key **result);
+int get_public_key(const char *key_file, struct asymmetric_key **result);
/**
- * Deallocate an asymmetric key structure.
+ * Deallocate a public key.
*
* \param key Pointer to the key structure to free.
*
- * This must be called for any key obtained by get_asymmetric_key().
+ * This should be called for keys obtained by get_public_key() if the key is no
+ * longer needed.
*/
-void free_asymmetric_key(struct asymmetric_key *key);
+void free_public_key(struct asymmetric_key *key);
/**
diff --git a/gcrypt.c b/gcrypt.c
index ba8aadc6..8bbc82f3 100644
--- a/gcrypt.c
+++ b/gcrypt.c
@@ -659,8 +659,7 @@ free_blob:
return ret;
}
-int get_asymmetric_key(const char *key_file, int private,
- struct asymmetric_key **result)
+int get_public_key(const char *key_file, struct asymmetric_key **result)
{
int ret, ret2;
void *map;
@@ -669,8 +668,6 @@ int get_asymmetric_key(const char *key_file, int private,
gcry_sexp_t sexp;
struct asymmetric_key *key;
- if (private)
- return get_private_key(key_file, result);
ret = mmap_full_file(key_file, O_RDONLY, &map, &map_size, NULL);
if (ret < 0)
return ret;
@@ -700,7 +697,7 @@ unmap:
return ret;
}
-void free_asymmetric_key(struct asymmetric_key *key)
+void free_public_key(struct asymmetric_key *key)
{
if (!key)
return;
@@ -832,7 +829,8 @@ in_mpi_release:
key_release:
gcry_sexp_release(priv_key);
free_key:
- free_asymmetric_key(priv);
+ gcry_sexp_release(priv->sexp);
+ free(priv);
return ret;
}
diff --git a/user_list.c b/user_list.c
index 9c751244..23fe086f 100644
--- a/user_list.c
+++ b/user_list.c
@@ -48,7 +48,7 @@ static void populate_user_list(char *user_list_file)
if (strcmp(w, "user"))
continue;
PARA_DEBUG_LOG("found entry for user %s\n", n);
- ret = get_asymmetric_key(k, LOAD_PUBLIC_KEY, &pubkey);
+ ret = get_public_key(k, &pubkey);
if (ret < 0) {
PARA_NOTICE_LOG("skipping entry for user %s: %s\n", n,
para_strerror(-ret));
@@ -63,7 +63,7 @@ static void populate_user_list(char *user_list_file)
if (ret <= CHALLENGE_SIZE + 2 * SESSION_KEY_LEN + 41) {
PARA_WARNING_LOG("public key %s too short (%d)\n",
k, ret);
- free_asymmetric_key(pubkey);
+ free_public_key(pubkey);
continue;
}
u = para_malloc(sizeof(*u));
@@ -114,7 +114,7 @@ void init_user_list(char *user_list_file)
list_for_each_entry_safe(u, tmp, &user_list, node) {
list_del(&u->node);
free(u->name);
- free_asymmetric_key(u->pubkey);
+ free_public_key(u->pubkey);
free(u);
}
} else