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-rw-r--r--main/openssl/0001-Fix-IV-check-and-padding-removal.patch72
1 files changed, 72 insertions, 0 deletions
diff --git a/main/openssl/0001-Fix-IV-check-and-padding-removal.patch b/main/openssl/0001-Fix-IV-check-and-padding-removal.patch
new file mode 100644
index 0000000000..321791251f
--- /dev/null
+++ b/main/openssl/0001-Fix-IV-check-and-padding-removal.patch
@@ -0,0 +1,72 @@
+From 32cc2479b473c49ce869e57fded7e9a77b695c0d Mon Sep 17 00:00:00 2001
+From: "Dr. Stephen Henson" <steve@openssl.org>
+Date: Thu, 7 Feb 2013 21:06:37 +0000
+Subject: [PATCH] Fix IV check and padding removal.
+
+Fix the calculation that checks there is enough room in a record
+after removing padding and optional explicit IV. (by Steve)
+
+For AEAD remove the correct number of padding bytes (by Andy)
+---
+ ssl/s3_cbc.c | 33 ++++++++++++---------------------
+ 1 file changed, 12 insertions(+), 21 deletions(-)
+
+diff --git a/ssl/s3_cbc.c b/ssl/s3_cbc.c
+index ce77acd..0f60507 100644
+--- a/ssl/s3_cbc.c
++++ b/ssl/s3_cbc.c
+@@ -139,31 +139,22 @@ int tls1_cbc_remove_padding(const SSL* s,
+ unsigned mac_size)
+ {
+ unsigned padding_length, good, to_check, i;
+- const char has_explicit_iv =
+- s->version >= TLS1_1_VERSION || s->version == DTLS1_VERSION;
+- const unsigned overhead = 1 /* padding length byte */ +
+- mac_size +
+- (has_explicit_iv ? block_size : 0);
+-
+- /* These lengths are all public so we can test them in non-constant
+- * time. */
+- if (overhead > rec->length)
+- return 0;
+-
+- /* We can always safely skip the explicit IV. We check at the beginning
+- * of this function that the record has at least enough space for the
+- * IV, MAC and padding length byte. (These can be checked in
+- * non-constant time because it's all public information.) So, if the
+- * padding was invalid, then we didn't change |rec->length| and this is
+- * safe. If the padding was valid then we know that we have at least
+- * overhead+padding_length bytes of space and so this is still safe
+- * because overhead accounts for the explicit IV. */
+- if (has_explicit_iv)
++ const unsigned overhead = 1 /* padding length byte */ + mac_size;
++ /* Check if version requires explicit IV */
++ if (s->version >= TLS1_1_VERSION || s->version == DTLS1_VERSION)
+ {
++ /* These lengths are all public so we can test them in
++ * non-constant time.
++ */
++ if (overhead + block_size > rec->length)
++ return 0;
++ /* We can now safely skip explicit IV */
+ rec->data += block_size;
+ rec->input += block_size;
+ rec->length -= block_size;
+ }
++ else if (overhead > rec->length)
++ return 0;
+
+ padding_length = rec->data[rec->length-1];
+
+@@ -190,7 +181,7 @@ int tls1_cbc_remove_padding(const SSL* s,
+ if (EVP_CIPHER_flags(s->enc_read_ctx->cipher)&EVP_CIPH_FLAG_AEAD_CIPHER)
+ {
+ /* padding is already verified */
+- rec->length -= padding_length;
++ rec->length -= padding_length + 1;
+ return 1;
+ }
+
+--
+1.8.1.2
+