Extract common logic in OpenSSL-specific code

[tinc] / src / openssl / cipher.c

diff --git a/src/openssl/cipher.c b/src/openssl/cipher.c
index 77747f1..77538b1 100644 (file)
--- a/src/openssl/cipher.c
+++ b/src/openssl/cipher.c
@@ -27,6 +27,10 @@
 #include "../cipher.h"
 #include "../logger.h"
 
+typedef int (enc_init_t)(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl, const unsigned char *key, const unsigned char *iv);
+typedef int (enc_update_t)(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl, const unsigned char *in, int inl);
+typedef int (enc_final_t)(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl);
+
 static void cipher_open(cipher_t *cipher, const EVP_CIPHER *evp_cipher) {
        cipher->cipher = evp_cipher;
        cipher->ctx = EVP_CIPHER_CTX_new();
@@ -107,13 +111,13 @@ size_t cipher_blocksize(const cipher_t *cipher) {
        return EVP_CIPHER_block_size(cipher->cipher);
 }
 
-bool cipher_set_key(cipher_t *cipher, void *key, bool encrypt) {
+static bool cipher_init_ctx(cipher_t *cipher, bool encrypt, const unsigned char *key, const unsigned char *iv) {
        bool result;
 
        if(encrypt) {
-               result = EVP_EncryptInit_ex(cipher->ctx, cipher->cipher, NULL, (unsigned char *)key, (unsigned char *)key + EVP_CIPHER_key_length(cipher->cipher));
+               result = EVP_EncryptInit_ex(cipher->ctx, cipher->cipher, NULL, key, iv);
        } else {
-               result = EVP_DecryptInit_ex(cipher->ctx, cipher->cipher, NULL, (unsigned char *)key, (unsigned char *)key + EVP_CIPHER_key_length(cipher->cipher));
+               result = EVP_DecryptInit_ex(cipher->ctx, cipher->cipher, NULL, key, iv);
        }
 
        if(result) {
@@ -124,30 +128,25 @@ bool cipher_set_key(cipher_t *cipher, void *key, bool encrypt) {
        return false;
 }
 
-bool cipher_set_key_from_rsa(cipher_t *cipher, void *key, size_t len, bool encrypt) {
-       bool result;
-
-       if(encrypt) {
-               result = EVP_EncryptInit_ex(cipher->ctx, cipher->cipher, NULL, (unsigned char *)key + len - EVP_CIPHER_key_length(cipher->cipher), (unsigned char *)key + len - EVP_CIPHER_iv_length(cipher->cipher) - EVP_CIPHER_key_length(cipher->cipher));
-       } else {
-               result = EVP_DecryptInit_ex(cipher->ctx, cipher->cipher, NULL, (unsigned char *)key + len - EVP_CIPHER_key_length(cipher->cipher), (unsigned char *)key + len - EVP_CIPHER_iv_length(cipher->cipher) - EVP_CIPHER_key_length(cipher->cipher));
-       }
-
-       if(result) {
-               return true;
-       }
+bool cipher_set_key(cipher_t *cipher, void *key, bool encrypt) {
+       unsigned char *iv = (unsigned char *)key + EVP_CIPHER_key_length(cipher->cipher);
+       return cipher_init_ctx(cipher, encrypt, key, iv);
+}
 
-       openssl_err("set key");
-       return false;
+bool cipher_set_key_from_rsa(cipher_t *cipher, void *key, size_t len, bool encrypt) {
+       unsigned char *k = (unsigned char *)key + len - EVP_CIPHER_key_length(cipher->cipher);
+       unsigned char *iv = k - EVP_CIPHER_iv_length(cipher->cipher);
+       return cipher_init_ctx(cipher, encrypt, k, iv);
 }
 
-bool cipher_encrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen, bool oneshot) {
+static bool cipher_encrypt_decrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen, bool oneshot,
+                                   enc_init_t init, enc_update_t update, enc_final_t final) {
        if(oneshot) {
                int len, pad;
 
-               if(EVP_EncryptInit_ex(cipher->ctx, NULL, NULL, NULL, NULL)
-                               && EVP_EncryptUpdate(cipher->ctx, (unsigned char *)outdata, &len, indata, (int)inlen)
-                               && EVP_EncryptFinal_ex(cipher->ctx, (unsigned char *)outdata + len, &pad)) {
+               if(init(cipher->ctx, NULL, NULL, NULL, NULL)
+                               && update(cipher->ctx, (unsigned char *)outdata, &len, indata, (int)inlen)
+                               && final(cipher->ctx, (unsigned char *)outdata + len, &pad)) {
                        if(outlen) {
                                *outlen = len + pad;
                        }
@@ -157,7 +156,7 @@ bool cipher_encrypt(cipher_t *cipher, const void *indata, size_t inlen, void *ou
        } else {
                int len;
 
-               if(EVP_EncryptUpdate(cipher->ctx, outdata, &len, indata, (int)inlen)) {
+               if(update(cipher->ctx, outdata, &len, indata, (int)inlen)) {
                        if(outlen) {
                                *outlen = len;
                        }
@@ -166,37 +165,18 @@ bool cipher_encrypt(cipher_t *cipher, const void *indata, size_t inlen, void *ou
                }
        }
 
-       openssl_err("encrypt data");
+       openssl_err("encrypt or decrypt data");
        return false;
 }
 
-bool cipher_decrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen, bool oneshot) {
-       if(oneshot) {
-               int len, pad;
-
-               if(EVP_DecryptInit_ex(cipher->ctx, NULL, NULL, NULL, NULL)
-                               && EVP_DecryptUpdate(cipher->ctx, (unsigned char *)outdata, &len, indata, (int)inlen)
-                               && EVP_DecryptFinal_ex(cipher->ctx, (unsigned char *)outdata + len, &pad)) {
-                       if(outlen) {
-                               *outlen = len + pad;
-                       }
-
-                       return true;
-               }
-       } else {
-               int len;
-
-               if(EVP_DecryptUpdate(cipher->ctx, outdata, &len, indata, (int)inlen)) {
-                       if(outlen) {
-                               *outlen = len;
-                       }
-
-                       return true;
-               }
-       }
+bool cipher_encrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen, bool oneshot) {
+       return cipher_encrypt_decrypt(cipher, indata, inlen, outdata, outlen, oneshot,
+                                     EVP_EncryptInit_ex, EVP_EncryptUpdate, EVP_EncryptFinal_ex);
+}
 
-       openssl_err("decrypt data");
-       return false;
+bool cipher_decrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen, bool oneshot) {
+       return cipher_encrypt_decrypt(cipher, indata, inlen, outdata, outlen, oneshot,
+                                     EVP_DecryptInit_ex, EVP_DecryptUpdate, EVP_DecryptFinal_ex);
 }
 
 int cipher_get_nid(const cipher_t *cipher) {