Move block crypt functionality to a new file

1 files changed, 85 insertions, 0 deletions

diff --git a/lib/crypto/c_src/block.c b/lib/crypto/c_src/block.c
new file mode 100644
index 0000000000..1366a90777
--- /dev/null
+++ b/lib/crypto/c_src/block.c
@@ -0,0 +1,85 @@
+#include "block.h"
+#include "aes.h"
+#include "cipher.h"
+
+ERL_NIF_TERM block_crypt_nif(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{/* (Type, Key, Ivec, Text, IsEncrypt) or (Type, Key, Text, IsEncrypt) */
+    struct cipher_type_t *cipherp = NULL;
+    const EVP_CIPHER     *cipher;
+    ErlNifBinary         key, ivec, text;
+    EVP_CIPHER_CTX*      ctx;
+    ERL_NIF_TERM         ret;
+    unsigned char        *out;
+    int                  ivec_size, out_size = 0;
+
+    if (!enif_inspect_iolist_as_binary(env, argv[1], &key)
+        || !(cipherp = get_cipher_type(argv[0], key.size))
+        || !enif_inspect_iolist_as_binary(env, argv[argc - 2], &text)) {
+        return enif_make_badarg(env);
+    }
+    cipher = cipherp->cipher.p;
+    if (!cipher) {
+        return enif_raise_exception(env, atom_notsup);
+    }
+
+    if (argv[0] == atom_aes_cfb8
+        && (key.size == 24 || key.size == 32)) {
+        /* Why do EVP_CIPHER_CTX_set_key_length() fail on these key sizes?
+         * Fall back on low level API
+         */
+        return aes_cfb_8_crypt(env, argc-1, argv+1);
+    }
+    else if (argv[0] == atom_aes_cfb128
+        && (key.size == 24 || key.size == 32)) {
+        /* Why do EVP_CIPHER_CTX_set_key_length() fail on these key sizes?
+         * Fall back on low level API
+         */
+        return aes_cfb_128_crypt_nif(env, argc-1, argv+1);
+   }
+
+    ivec_size  = EVP_CIPHER_iv_length(cipher);
+
+#ifdef HAVE_ECB_IVEC_BUG
+    if (argv[0] == atom_aes_ecb || argv[0] == atom_blowfish_ecb ||
+	argv[0] == atom_des_ecb)
+	ivec_size = 0; /* 0.9.8l returns faulty ivec_size */
+#endif
+
+    if (text.size % EVP_CIPHER_block_size(cipher) != 0 ||
+        (ivec_size == 0 ? argc != 4
+                      : (argc != 5 ||
+                         !enif_inspect_iolist_as_binary(env, argv[2], &ivec) ||
+                         ivec.size != ivec_size))) {
+        return enif_make_badarg(env);
+    }
+
+    out = enif_make_new_binary(env, text.size, &ret);
+
+    ctx = EVP_CIPHER_CTX_new();
+    if (!EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL,
+                           (argv[argc - 1] == atom_true)) ||
+        !EVP_CIPHER_CTX_set_key_length(ctx, key.size) ||
+        !(EVP_CIPHER_type(cipher) != NID_rc2_cbc ||
+          EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_SET_RC2_KEY_BITS, key.size * 8, NULL)) ||
+        !EVP_CipherInit_ex(ctx, NULL, NULL,
+                           key.data, ivec_size ? ivec.data : NULL, -1) ||
+        !EVP_CIPHER_CTX_set_padding(ctx, 0)) {
+
+        EVP_CIPHER_CTX_free(ctx);
+        return enif_raise_exception(env, atom_notsup);
+    }
+
+    if (text.size > 0 && /* OpenSSL 0.9.8h asserts text.size > 0 */
+        (!EVP_CipherUpdate(ctx, out, &out_size, text.data, text.size)
+         || (ASSERT(out_size == text.size), 0)
+         || !EVP_CipherFinal_ex(ctx, out + out_size, &out_size))) {
+
+        EVP_CIPHER_CTX_free(ctx);
+        return enif_raise_exception(env, atom_notsup);
+    }
+    ASSERT(out_size == 0);
+    EVP_CIPHER_CTX_free(ctx);
+    CONSUME_REDS(env, text);
+
+    return ret;
+}