[openssh] enable aes-ctr ciphers use the EVP engines from OpenSSL such as the AES-NI

[Tomáš Mráz]

commit 6148abd5854cf36ae2f5930af5a5e5740553f933
Author: Tomas Mraz <tmraz at fedoraproject.org>
Date:   Wed Jan 11 19:11:33 2012 +0100

    enable aes-ctr ciphers use the EVP engines from OpenSSL such as the AES-NI

 openssh-5.9p1-ctr-evp-fast.patch |  101 ++++++++++++++++++++++++++++++++++++++
 openssh.spec                     |    9 +++-
 2 files changed, 108 insertions(+), 2 deletions(-)
---
diff --git a/openssh-5.9p1-ctr-evp-fast.patch b/openssh-5.9p1-ctr-evp-fast.patch
new file mode 100644
index 0000000..5d17aab
--- /dev/null
+++ b/openssh-5.9p1-ctr-evp-fast.patch
@@ -0,0 +1,101 @@
+diff -up openssh-5.9p1/cipher-ctr.c.ctr-evp openssh-5.9p1/cipher-ctr.c
+--- openssh-5.9p1/cipher-ctr.c.ctr-evp	2012-01-11 09:24:06.000000000 +0100
++++ openssh-5.9p1/cipher-ctr.c	2012-01-11 15:54:04.675956600 +0100
+@@ -38,7 +38,7 @@ void ssh_aes_ctr_iv(EVP_CIPHER_CTX *, in
+ 
+ struct ssh_aes_ctr_ctx
+ {
+-	AES_KEY		aes_ctx;
++	EVP_CIPHER_CTX	ecbctx;
+ 	u_char		aes_counter[AES_BLOCK_SIZE];
+ };
+ 
+@@ -63,21 +63,42 @@ ssh_aes_ctr(EVP_CIPHER_CTX *ctx, u_char
+ {
+ 	struct ssh_aes_ctr_ctx *c;
+ 	size_t n = 0;
+-	u_char buf[AES_BLOCK_SIZE];
++	u_char ctrbuf[AES_BLOCK_SIZE*256];
++	u_char buf[AES_BLOCK_SIZE*256];
+ 
+ 	if (len == 0)
+ 		return (1);
+ 	if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) == NULL)
+ 		return (0);
+ 
+-	while ((len--) > 0) {
++	for (; len > 0; len -= sizeof(u_int)) {
++		u_int r,a,b;
++
+ 		if (n == 0) {
+-			AES_encrypt(c->aes_counter, buf, &c->aes_ctx);
+-			ssh_ctr_inc(c->aes_counter, AES_BLOCK_SIZE);
++			int outl, i, buflen;
++
++			buflen = MIN(len, sizeof(ctrbuf));
++
++			for(i = 0; i < buflen; i += AES_BLOCK_SIZE) {
++				memcpy(&ctrbuf[i], c->aes_counter, AES_BLOCK_SIZE);
++				ssh_ctr_inc(c->aes_counter, AES_BLOCK_SIZE);
++			}
++
++			EVP_EncryptUpdate(&c->ecbctx, buf, &outl,
++				ctrbuf, buflen);
+ 		}
+-		*(dest++) = *(src++) ^ buf[n];
+-		n = (n + 1) % AES_BLOCK_SIZE;
++
++		memcpy(&a, src, sizeof(a));
++		memcpy(&b, &buf[n], sizeof(b));
++		r = a ^ b;
++		memcpy(dest, &r, sizeof(r));
++		src += sizeof(a);
++		dest += sizeof(r);
++
++		n = (n + sizeof(b)) % sizeof(buf);
+ 	}
++	memset(ctrbuf, '\0', sizeof(ctrbuf));
++	memset(buf, '\0', sizeof(buf));
+ 	return (1);
+ }
+ 
+@@ -91,9 +112,28 @@ ssh_aes_ctr_init(EVP_CIPHER_CTX *ctx, co
+ 		c = xmalloc(sizeof(*c));
+ 		EVP_CIPHER_CTX_set_app_data(ctx, c);
+ 	}
+-	if (key != NULL)
+-		AES_set_encrypt_key(key, EVP_CIPHER_CTX_key_length(ctx) * 8,
+-		    &c->aes_ctx);
++
++	EVP_CIPHER_CTX_init(&c->ecbctx);
++
++	if (key != NULL) {
++		const EVP_CIPHER *cipher;
++		switch(EVP_CIPHER_CTX_key_length(ctx)*8) {
++			case 128:
++				cipher = EVP_aes_128_ecb();
++				break;
++			case 192:
++				cipher = EVP_aes_192_ecb();
++				break;
++			case 256:
++				cipher = EVP_aes_256_ecb();
++				break;
++			default:
++				fatal("ssh_aes_ctr_init: wrong aes key length");
++		}
++		if(!EVP_EncryptInit_ex(&c->ecbctx, cipher, NULL, key, NULL))
++			fatal("ssh_aes_ctr_init: cannot initialize aes encryption");
++		EVP_CIPHER_CTX_set_padding(&c->ecbctx, 0);
++	}
+ 	if (iv != NULL)
+ 		memcpy(c->aes_counter, iv, AES_BLOCK_SIZE);
+ 	return (1);
+@@ -105,6 +145,7 @@ ssh_aes_ctr_cleanup(EVP_CIPHER_CTX *ctx)
+ 	struct ssh_aes_ctr_ctx *c;
+ 
+ 	if ((c = EVP_CIPHER_CTX_get_app_data(ctx)) != NULL) {
++		EVP_CIPHER_CTX_cleanup(&c->ecbctx);
+ 		memset(c, 0, sizeof(*c));
+ 		xfree(c);
+ 		EVP_CIPHER_CTX_set_app_data(ctx, NULL);
diff --git a/openssh.spec b/openssh.spec
index 0570c29..519e66b 100644
--- a/openssh.spec
+++ b/openssh.spec
@@ -75,7 +75,7 @@
 
 # Do not forget to bump pam_ssh_agent_auth release if you rewind the main package release to 1
 %define openssh_ver 5.9p1
-%define openssh_rel 14
+%define openssh_rel 15
 %define pam_ssh_agent_ver 0.9.2
 %define pam_ssh_agent_rel 32
 
@@ -196,7 +196,8 @@ Patch709: openssh-5.9p1-vendor.patch
 Patch710: openssh-5.9p1-copy-id-restorecon.patch
 # warn users for unsupported UsePAM=no (#757545)
 Patch711: openssh-5.9p1-log-usepam-no.patch
-
+# make aes-ctr ciphers use EVP engines such as AES-NI from OpenSSL
+Patch712: openssh-5.9p1-ctr-evp-fast.patch
 
 #http://www.sxw.org.uk/computing/patches/openssh.html
 Patch800: openssh-5.9p1-gsskex.patch
@@ -444,6 +445,7 @@ popd
 %patch709 -p1 -b .vendor
 %patch710 -p1 -b .restorecon
 %patch711 -p1 -b .log-usepam-no
+%patch712 -p1 -b .evp-ctr
 
 %patch800 -p1 -b .gsskex
 %patch801 -p1 -b .force_krb
@@ -789,6 +791,9 @@ fi
 %endif
 
 %changelog
+* Tue Dec 06 2011 Tomas Mraz <tmraz at redhat.com> 5.9p1-15 + 0.9.2-32
+- enable aes-ctr ciphers use the EVP engines from OpenSSL such as the AES-NI
+
 * Tue Dec 06 2011 Petr Lautrbach <plautrba at redhat.com> 5.9p1-14 + 0.9.2-32
 - warn about unsupported option UsePAM=no (#757545)