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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 17:32:43 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 17:32:43 +0000
commit6bf0a5cb5034a7e684dcc3500e841785237ce2dd (patch)
treea68f146d7fa01f0134297619fbe7e33db084e0aa /comm/third_party/libotr/toolkit/ctrmode.c
parentInitial commit. (diff)
downloadthunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.tar.xz
thunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.zip
Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'comm/third_party/libotr/toolkit/ctrmode.c')
-rw-r--r--comm/third_party/libotr/toolkit/ctrmode.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/comm/third_party/libotr/toolkit/ctrmode.c b/comm/third_party/libotr/toolkit/ctrmode.c
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+++ b/comm/third_party/libotr/toolkit/ctrmode.c
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+/*
+ * Off-the-Record Messaging Toolkit
+ * Copyright (C) 2004-2012 Ian Goldberg, Chris Alexander, Nikita Borisov
+ * <otr@cypherpunks.ca>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/* system headers */
+#include <stdlib.h>
+#include <string.h>
+
+/* toolkit headers */
+#include "aes.h"
+
+/* Encrypt or decrypt data in AES-CTR mode. (The operations are the
+ * same.) We roll our own here just to double-check that the calls
+ * libotr makes to libgcrypt are doing the right thing. */
+void aes_ctr_crypt(unsigned char *out, const unsigned char *in, size_t len,
+ unsigned char key[16], unsigned char ctrtop[8])
+{
+ unsigned char ctr[16], encctr[16];
+ aes_context aesc;
+
+ aes_set_key(&aesc, key, 128);
+
+ memmove(ctr, ctrtop, 8);
+ memset(ctr+8, 0, 8);
+
+ while(len > 0) {
+ /* How much to do at a time? */
+ size_t i;
+ size_t amt = len;
+ if (amt > 16) amt = 16;
+ aes_encrypt(&aesc, ctr, encctr);
+ for(i=0;i<amt;++i) {
+ out[i] = in[i] ^ encctr[i];
+ }
+
+ /* Increment the counter */
+ for (i=16;i>0;--i) {
+ if (++ctr[i-1] != 0) break;
+ }
+
+ out += amt;
+ in += amt;
+ len -= amt;
+ }
+}