Merge branch 'debian/experimental-2.5'

1 files changed, 214 insertions, 71 deletions

diff --git a/src/openvpn/crypto_openssl.c b/src/openvpn/crypto_openssl.c
index 3abcc99..c60d4a5 100644
--- a/src/openvpn/crypto_openssl.c
+++ b/src/openvpn/crypto_openssl.c
@@ -34,7 +34,7 @@
 
 #include "syshead.h"
 
-#if defined(ENABLE_CRYPTO) && defined(ENABLE_CRYPTO_OPENSSL)
+#if defined(ENABLE_CRYPTO_OPENSSL)
 
 #include "basic.h"
 #include "buffer.h"
@@ -43,6 +43,7 @@
 #include "crypto_backend.h"
 #include "openssl_compat.h"
 
+#include <openssl/conf.h>
 #include <openssl/des.h>
 #include <openssl/err.h>
 #include <openssl/evp.h>
@@ -63,6 +64,7 @@
 #endif
 
 #if HAVE_OPENSSL_ENGINE
+#include <openssl/ui.h>
 #include <openssl/engine.h>
 
 static bool engine_initialized = false; /* GLOBAL */
@@ -148,6 +150,11 @@ crypto_init_lib_engine(const char *engine_name)
 void
 crypto_init_lib(void)
 {
+#if (OPENSSL_VERSION_NUMBER >= 0x10100000L)
+    OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL);
+#else
+    OPENSSL_config(NULL);
+#endif
     /*
      * If you build the OpenSSL library and OpenVPN with
      * CRYPTO_MDEBUG, you will get a listing of OpenSSL
@@ -202,12 +209,12 @@ crypto_print_openssl_errors(const unsigned int flags)
         else if (ERR_GET_REASON(err) == SSL_R_UNSUPPORTED_PROTOCOL)
         {
             msg(D_CRYPT_ERRORS, "TLS error: Unsupported protocol. This typically "
-                 "indicates that client and server have no common TLS version enabled. "
-                 "This can be caused by mismatched tls-version-min and tls-version-max "
-                 "options on client and server. "
-                 "If your OpenVPN client is between v2.3.6 and v2.3.2 try adding "
-                 "tls-version-min 1.0 to the client configuration to use TLS 1.0+ "
-                 "instead of TLS 1.0 only");
+                "indicates that client and server have no common TLS version enabled. "
+                "This can be caused by mismatched tls-version-min and tls-version-max "
+                "options on client and server. "
+                "If your OpenVPN client is between v2.3.6 and v2.3.2 try adding "
+                "tls-version-min 1.0 to the client configuration to use TLS 1.0+ "
+                "instead of TLS 1.0 only");
         }
         msg(flags, "OpenSSL: %s", ERR_error_string(err, NULL));
     }
@@ -254,6 +261,7 @@ const cipher_name_pair cipher_name_translation_table[] = {
     { "AES-128-GCM", "id-aes128-GCM" },
     { "AES-192-GCM", "id-aes192-GCM" },
     { "AES-256-GCM", "id-aes256-GCM" },
+    { "CHACHA20-POLY1305", "ChaCha20-Poly1305" },
 };
 const size_t cipher_name_translation_table_count =
     sizeof(cipher_name_translation_table) / sizeof(*cipher_name_translation_table);
@@ -265,27 +273,7 @@ cipher_name_cmp(const void *a, const void *b)
     const EVP_CIPHER *const *cipher_a = a;
     const EVP_CIPHER *const *cipher_b = b;
 
-    const char *cipher_name_a =
-        translate_cipher_name_to_openvpn(EVP_CIPHER_name(*cipher_a));
-    const char *cipher_name_b =
-        translate_cipher_name_to_openvpn(EVP_CIPHER_name(*cipher_b));
-
-    return strcmp(cipher_name_a, cipher_name_b);
-}
-
-static void
-print_cipher(const EVP_CIPHER *cipher)
-{
-    const char *var_key_size =
-        (EVP_CIPHER_flags(cipher) & EVP_CIPH_VARIABLE_LENGTH) ?
-        " by default" : "";
-    const char *ssl_only = cipher_kt_mode_cbc(cipher) ?
-                           "" : ", TLS client/server mode only";
-
-    printf("%s  (%d bit key%s, %d bit block%s)\n",
-           translate_cipher_name_to_openvpn(EVP_CIPHER_name(cipher)),
-           EVP_CIPHER_key_length(cipher) * 8, var_key_size,
-           cipher_kt_block_size(cipher) * 8, ssl_only);
+    return strcmp(cipher_kt_name(*cipher_a), cipher_kt_name(*cipher_b));
 }
 
 void
@@ -299,11 +287,11 @@ show_available_ciphers(void)
     size_t num_ciphers = 0;
 #ifndef ENABLE_SMALL
     printf("The following ciphers and cipher modes are available for use\n"
-           "with " PACKAGE_NAME ".  Each cipher shown below may be use as a\n"
-           "parameter to the --cipher option.  The default key size is\n"
-           "shown as well as whether or not it can be changed with the\n"
-           "--keysize directive.  Using a CBC or GCM mode is recommended.\n"
-           "In static key mode only CBC mode is allowed.\n\n");
+           "with " PACKAGE_NAME ".  Each cipher shown below may be used as a\n"
+           "parameter to the --data-ciphers (or --cipher) option.  The\n"
+           "default key size is shown as well as whether or not it can be\n"
+           "changed with the --keysize directive.  Using a GCM or CBC mode\n"
+           "is recommended.  In static key mode only CBC mode is allowed.\n\n");
 #endif
 
     for (nid = 0; nid < 10000; ++nid)
@@ -313,9 +301,7 @@ show_available_ciphers(void)
 #ifdef ENABLE_OFB_CFB_MODE
                        || cipher_kt_mode_ofb_cfb(cipher)
 #endif
-#ifdef HAVE_AEAD_CIPHER_MODES
                        || cipher_kt_mode_aead(cipher)
-#endif
                        ))
         {
             cipher_list[num_ciphers++] = cipher;
@@ -327,10 +313,12 @@ show_available_ciphers(void)
         }
     }
 
-    qsort(cipher_list, num_ciphers, sizeof(*cipher_list), cipher_name_cmp);
+    /* cast to non-const to prevent warning */
+    qsort((EVP_CIPHER *)cipher_list, num_ciphers, sizeof(*cipher_list), cipher_name_cmp);
 
-    for (i = 0; i < num_ciphers; i++) {
-        if (cipher_kt_block_size(cipher_list[i]) >= 128/8)
+    for (i = 0; i < num_ciphers; i++)
+    {
+        if (!cipher_kt_insecure(cipher_list[i]))
         {
             print_cipher(cipher_list[i]);
         }
@@ -338,8 +326,9 @@ show_available_ciphers(void)
 
     printf("\nThe following ciphers have a block size of less than 128 bits, \n"
            "and are therefore deprecated.  Do not use unless you have to.\n\n");
-    for (i = 0; i < num_ciphers; i++) {
-        if (cipher_kt_block_size(cipher_list[i]) < 128/8)
+    for (i = 0; i < num_ciphers; i++)
+    {
+        if (cipher_kt_insecure(cipher_list[i]))
         {
             print_cipher(cipher_list[i]);
         }
@@ -396,6 +385,88 @@ show_available_engines(void)
 #endif
 }
 
+
+bool
+crypto_pem_encode(const char *name, struct buffer *dst,
+                  const struct buffer *src, struct gc_arena *gc)
+{
+    bool ret = false;
+    BIO *bio = BIO_new(BIO_s_mem());
+    if (!bio || !PEM_write_bio(bio, name, "", BPTR(src), BLEN(src)))
+    {
+        ret = false;
+        goto cleanup;
+    }
+
+    BUF_MEM *bptr;
+    BIO_get_mem_ptr(bio, &bptr);
+
+    *dst = alloc_buf_gc(bptr->length, gc);
+    ASSERT(buf_write(dst, bptr->data, bptr->length));
+
+    ret = true;
+cleanup:
+    if (!BIO_free(bio))
+    {
+        ret = false;
+    }
+
+    return ret;
+}
+
+bool
+crypto_pem_decode(const char *name, struct buffer *dst,
+                  const struct buffer *src)
+{
+    bool ret = false;
+
+    BIO *bio = BIO_new_mem_buf((char *)BPTR(src), BLEN(src));
+    if (!bio)
+    {
+        crypto_msg(M_FATAL, "Cannot open memory BIO for PEM decode");
+    }
+
+    char *name_read = NULL;
+    char *header_read = NULL;
+    uint8_t *data_read = NULL;
+    long data_read_len = 0;
+    if (!PEM_read_bio(bio, &name_read, &header_read, &data_read,
+                      &data_read_len))
+    {
+        dmsg(D_CRYPT_ERRORS, "%s: PEM decode failed", __func__);
+        goto cleanup;
+    }
+
+    if (strcmp(name, name_read))
+    {
+        dmsg(D_CRYPT_ERRORS,
+             "%s: unexpected PEM name (got '%s', expected '%s')",
+             __func__, name_read, name);
+        goto cleanup;
+    }
+
+    uint8_t *dst_data = buf_write_alloc(dst, data_read_len);
+    if (!dst_data)
+    {
+        dmsg(D_CRYPT_ERRORS, "%s: dst too small (%i, needs %li)", __func__,
+             BCAP(dst), data_read_len);
+        goto cleanup;
+    }
+    memcpy(dst_data, data_read, data_read_len);
+
+    ret = true;
+cleanup:
+    OPENSSL_free(name_read);
+    OPENSSL_free(header_read);
+    OPENSSL_free(data_read);
+    if (!BIO_free(bio))
+    {
+        ret = false;
+    }
+
+    return ret;
+}
+
 /*
  *
  * Random number functions, used in cases where we want
@@ -515,6 +586,7 @@ cipher_kt_get(const char *ciphername)
 
     ASSERT(ciphername);
 
+    ciphername = translate_cipher_name_from_openvpn(ciphername);
     cipher = EVP_get_cipherbyname(ciphername);
 
     if (NULL == cipher)
@@ -543,7 +615,9 @@ cipher_kt_name(const EVP_CIPHER *cipher_kt)
     {
         return "[null-cipher]";
     }
-    return EVP_CIPHER_name(cipher_kt);
+
+    const char *name = EVP_CIPHER_name(cipher_kt);
+    return translate_cipher_name_to_openvpn(name);
 }
 
 int
@@ -574,7 +648,7 @@ cipher_kt_block_size(const EVP_CIPHER *cipher)
 
     int block_size = EVP_CIPHER_block_size(cipher);
 
-    orig_name = cipher_kt_name(cipher);
+    orig_name = EVP_CIPHER_name(cipher);
     if (!orig_name)
     {
         goto cleanup;
@@ -613,6 +687,16 @@ cipher_kt_tag_size(const EVP_CIPHER *cipher_kt)
     }
 }
 
+bool
+cipher_kt_insecure(const EVP_CIPHER *cipher)
+{
+    return !(cipher_kt_block_size(cipher) >= 128 / 8
+#ifdef NID_chacha20_poly1305
+             || EVP_CIPHER_nid(cipher) == NID_chacha20_poly1305
+#endif
+             );
+}
+
 int
 cipher_kt_mode(const EVP_CIPHER *cipher_kt)
 {
@@ -624,11 +708,8 @@ bool
 cipher_kt_mode_cbc(const cipher_kt_t *cipher)
 {
     return cipher && cipher_kt_mode(cipher) == OPENVPN_MODE_CBC
-#ifdef EVP_CIPH_FLAG_AEAD_CIPHER
            /* Exclude AEAD cipher modes, they require a different API */
-           && !(EVP_CIPHER_flags(cipher) & EVP_CIPH_FLAG_AEAD_CIPHER)
-#endif
-    ;
+           && !(EVP_CIPHER_flags(cipher) & EVP_CIPH_FLAG_AEAD_CIPHER);
 }
 
 bool
@@ -636,21 +717,28 @@ cipher_kt_mode_ofb_cfb(const cipher_kt_t *cipher)
 {
     return cipher && (cipher_kt_mode(cipher) == OPENVPN_MODE_OFB
                       || cipher_kt_mode(cipher) == OPENVPN_MODE_CFB)
-#ifdef EVP_CIPH_FLAG_AEAD_CIPHER
            /* Exclude AEAD cipher modes, they require a different API */
-           && !(EVP_CIPHER_flags(cipher) & EVP_CIPH_FLAG_AEAD_CIPHER)
-#endif
-    ;
+           && !(EVP_CIPHER_flags(cipher) & EVP_CIPH_FLAG_AEAD_CIPHER);
 }
 
 bool
 cipher_kt_mode_aead(const cipher_kt_t *cipher)
 {
-#ifdef HAVE_AEAD_CIPHER_MODES
-    return cipher && (cipher_kt_mode(cipher) == OPENVPN_MODE_GCM);
-#else
-    return false;
+    if (cipher)
+    {
+        switch (EVP_CIPHER_nid(cipher))
+        {
+            case NID_aes_128_gcm:
+            case NID_aes_192_gcm:
+            case NID_aes_256_gcm:
+#ifdef NID_chacha20_poly1305
+            case NID_chacha20_poly1305:
 #endif
+                return true;
+        }
+    }
+
+    return false;
 }
 
 /*
@@ -708,11 +796,7 @@ cipher_ctx_iv_length(const EVP_CIPHER_CTX *ctx)
 int
 cipher_ctx_get_tag(EVP_CIPHER_CTX *ctx, uint8_t *tag_buf, int tag_size)
 {
-#ifdef HAVE_AEAD_CIPHER_MODES
     return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_GET_TAG, tag_size, tag_buf);
-#else
-    ASSERT(0);
-#endif
 }
 
 int
@@ -735,7 +819,7 @@ cipher_ctx_get_cipher_kt(const cipher_ctx_t *ctx)
 
 
 int
-cipher_ctx_reset(EVP_CIPHER_CTX *ctx, uint8_t *iv_buf)
+cipher_ctx_reset(EVP_CIPHER_CTX *ctx, const uint8_t *iv_buf)
 {
     return EVP_CipherInit_ex(ctx, NULL, NULL, NULL, iv_buf, -1);
 }
@@ -743,16 +827,12 @@ cipher_ctx_reset(EVP_CIPHER_CTX *ctx, uint8_t *iv_buf)
 int
 cipher_ctx_update_ad(EVP_CIPHER_CTX *ctx, const uint8_t *src, int src_len)
 {
-#ifdef HAVE_AEAD_CIPHER_MODES
     int len;
     if (!EVP_CipherUpdate(ctx, NULL, &len, src, src_len))
     {
         crypto_msg(M_FATAL, "%s: EVP_CipherUpdate() failed", __func__);
     }
     return 1;
-#else  /* ifdef HAVE_AEAD_CIPHER_MODES */
-    ASSERT(0);
-#endif
 }
 
 int
@@ -776,7 +856,6 @@ int
 cipher_ctx_final_check_tag(EVP_CIPHER_CTX *ctx, uint8_t *dst, int *dst_len,
                            uint8_t *tag, size_t tag_len)
 {
-#ifdef HAVE_AEAD_CIPHER_MODES
     ASSERT(tag_len < SIZE_MAX);
     if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, tag_len, tag))
     {
@@ -784,9 +863,6 @@ cipher_ctx_final_check_tag(EVP_CIPHER_CTX *ctx, uint8_t *dst, int *dst_len,
     }
 
     return cipher_ctx_final(ctx, dst, dst_len);
-#else  /* ifdef HAVE_AEAD_CIPHER_MODES */
-    ASSERT(0);
-#endif
 }
 
 void
@@ -837,10 +913,10 @@ md_kt_name(const EVP_MD *kt)
     return EVP_MD_name(kt);
 }
 
-int
+unsigned char
 md_kt_size(const EVP_MD *kt)
 {
-    return EVP_MD_size(kt);
+    return (unsigned char)EVP_MD_size(kt);
 }
 
 
@@ -866,7 +942,8 @@ md_ctx_new(void)
     return ctx;
 }
 
-void md_ctx_free(EVP_MD_CTX *ctx)
+void
+md_ctx_free(EVP_MD_CTX *ctx)
 {
     EVP_MD_CTX_free(ctx);
 }
@@ -972,4 +1049,70 @@ hmac_ctx_final(HMAC_CTX *ctx, uint8_t *dst)
     HMAC_Final(ctx, dst, &in_hmac_len);
 }
 
-#endif /* ENABLE_CRYPTO && ENABLE_CRYPTO_OPENSSL */
+int
+memcmp_constant_time(const void *a, const void *b, size_t size)
+{
+    return CRYPTO_memcmp(a, b, size);
+}
+
+#if HAVE_OPENSSL_ENGINE
+static int
+ui_reader(UI *ui, UI_STRING *uis)
+{
+    SSL_CTX *ctx = UI_get0_user_data(ui);
+
+    if (UI_get_string_type(uis) == UIT_PROMPT)
+    {
+        pem_password_cb *cb = SSL_CTX_get_default_passwd_cb(ctx);
+        void *d = SSL_CTX_get_default_passwd_cb_userdata(ctx);
+        char password[64];
+
+        cb(password, sizeof(password), 0, d);
+        UI_set_result(ui, uis, password);
+
+        return 1;
+    }
+    return 0;
+}
+#endif
+
+EVP_PKEY *
+engine_load_key(const char *file, SSL_CTX *ctx)
+{
+#if HAVE_OPENSSL_ENGINE
+    UI_METHOD *ui;
+    EVP_PKEY *pkey;
+
+    if (!engine_persist)
+    {
+        return NULL;
+    }
+
+    /* this will print out the error from BIO_read */
+    crypto_msg(M_INFO, "PEM_read_bio failed, now trying engine method to load private key");
+
+    ui = UI_create_method("openvpn");
+    if (!ui)
+    {
+        crypto_msg(M_FATAL, "Engine UI creation failed");
+        return NULL;
+    }
+
+    UI_method_set_reader(ui, ui_reader);
+
+    ENGINE_init(engine_persist);
+    pkey = ENGINE_load_private_key(engine_persist, file, ui, ctx);
+    ENGINE_finish(engine_persist);
+    if (!pkey)
+    {
+        crypto_msg(M_FATAL, "Engine could not load key file");
+    }
+
+    UI_destroy_method(ui);
+    return pkey;
+#else  /* if HAVE_OPENSSL_ENGINE */
+    return NULL;
+#endif /* if HAVE_OPENSSL_ENGINE */
+}
+
+#endif /* ENABLE_CRYPTO_OPENSSL */