Put ssh back into the repository

Change-Id: I23324372188fa6ed3f93a32b84365f5df6367590
diff --git a/compat.c b/compat.c
new file mode 100644
index 0000000..df3541d
--- /dev/null
+++ b/compat.c
@@ -0,0 +1,237 @@
+/* $OpenBSD: compat.c,v 1.78 2008/09/11 14:22:37 markus Exp $ */
+/*
+ * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+
+#include <sys/types.h>
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+
+#include "xmalloc.h"
+#include "buffer.h"
+#include "packet.h"
+#include "compat.h"
+#include "log.h"
+#include "match.h"
+
+int compat13 = 0;
+int compat20 = 0;
+int datafellows = 0;
+
+void
+enable_compat20(void)
+{
+	debug("Enabling compatibility mode for protocol 2.0");
+	compat20 = 1;
+}
+void
+enable_compat13(void)
+{
+	debug("Enabling compatibility mode for protocol 1.3");
+	compat13 = 1;
+}
+/* datafellows bug compatibility */
+void
+compat_datafellows(const char *version)
+{
+	int i;
+	static struct {
+		char	*pat;
+		int	bugs;
+	} check[] = {
+		{ "OpenSSH-2.0*,"
+		  "OpenSSH-2.1*,"
+		  "OpenSSH_2.1*,"
+		  "OpenSSH_2.2*",	SSH_OLD_SESSIONID|SSH_BUG_BANNER|
+					SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
+					SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
+		{ "OpenSSH_2.3.0*",	SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES|
+					SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
+					SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
+		{ "OpenSSH_2.3.*",	SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
+					SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
+					SSH_OLD_FORWARD_ADDR},
+		{ "OpenSSH_2.5.0p1*,"
+		  "OpenSSH_2.5.1p1*",
+					SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
+					SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
+					SSH_OLD_FORWARD_ADDR},
+		{ "OpenSSH_2.5.0*,"
+		  "OpenSSH_2.5.1*,"
+		  "OpenSSH_2.5.2*",	SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
+					SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
+		{ "OpenSSH_2.5.3*",	SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
+					SSH_OLD_FORWARD_ADDR},
+		{ "OpenSSH_2.*,"
+		  "OpenSSH_3.0*,"
+		  "OpenSSH_3.1*",	SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
+		{ "OpenSSH_3.*",	SSH_OLD_FORWARD_ADDR },
+		{ "Sun_SSH_1.0*",	SSH_BUG_NOREKEY|SSH_BUG_EXTEOF},
+		{ "OpenSSH_4*",		0 },
+		{ "OpenSSH*",		SSH_NEW_OPENSSH },
+		{ "*MindTerm*",		0 },
+		{ "2.1.0*",		SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
+					SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
+					SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE|
+					SSH_BUG_FIRSTKEX },
+		{ "2.1 *",		SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
+					SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
+					SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE|
+					SSH_BUG_FIRSTKEX },
+		{ "2.0.13*,"
+		  "2.0.14*,"
+		  "2.0.15*,"
+		  "2.0.16*,"
+		  "2.0.17*,"
+		  "2.0.18*,"
+		  "2.0.19*",		SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
+					SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
+					SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
+					SSH_BUG_PKOK|SSH_BUG_RSASIGMD5|
+					SSH_BUG_HBSERVICE|SSH_BUG_OPENFAILURE|
+					SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX },
+		{ "2.0.11*,"
+		  "2.0.12*",		SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
+					SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
+					SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
+					SSH_BUG_PKAUTH|SSH_BUG_PKOK|
+					SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE|
+					SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX },
+		{ "2.0.*",		SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
+					SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
+					SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
+					SSH_BUG_PKAUTH|SSH_BUG_PKOK|
+					SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE|
+					SSH_BUG_DERIVEKEY|SSH_BUG_DUMMYCHAN|
+					SSH_BUG_FIRSTKEX },
+		{ "2.2.0*,"
+		  "2.3.0*",		SSH_BUG_HMAC|SSH_BUG_DEBUG|
+					SSH_BUG_RSASIGMD5|SSH_BUG_FIRSTKEX },
+		{ "2.3.*",		SSH_BUG_DEBUG|SSH_BUG_RSASIGMD5|
+					SSH_BUG_FIRSTKEX },
+		{ "2.4",		SSH_OLD_SESSIONID },	/* Van Dyke */
+		{ "2.*",		SSH_BUG_DEBUG|SSH_BUG_FIRSTKEX|
+					SSH_BUG_RFWD_ADDR },
+		{ "3.0.*",		SSH_BUG_DEBUG },
+		{ "3.0 SecureCRT*",	SSH_OLD_SESSIONID },
+		{ "1.7 SecureFX*",	SSH_OLD_SESSIONID },
+		{ "1.2.18*,"
+		  "1.2.19*,"
+		  "1.2.20*,"
+		  "1.2.21*,"
+		  "1.2.22*",		SSH_BUG_IGNOREMSG },
+		{ "1.3.2*",		/* F-Secure */
+					SSH_BUG_IGNOREMSG },
+		{ "*SSH Compatible Server*",			/* Netscreen */
+					SSH_BUG_PASSWORDPAD },
+		{ "*OSU_0*,"
+		  "OSU_1.0*,"
+		  "OSU_1.1*,"
+		  "OSU_1.2*,"
+		  "OSU_1.3*,"
+		  "OSU_1.4*,"
+		  "OSU_1.5alpha1*,"
+		  "OSU_1.5alpha2*,"
+		  "OSU_1.5alpha3*",	SSH_BUG_PASSWORDPAD },
+		{ "*SSH_Version_Mapper*",
+					SSH_BUG_SCANNER },
+		{ "Probe-*",
+					SSH_BUG_PROBE },
+		{ NULL,			0 }
+	};
+
+	/* process table, return first match */
+	for (i = 0; check[i].pat; i++) {
+		if (match_pattern_list(version, check[i].pat,
+		    strlen(check[i].pat), 0) == 1) {
+			debug("match: %s pat %s", version, check[i].pat);
+			datafellows = check[i].bugs;
+			return;
+		}
+	}
+	debug("no match: %s", version);
+}
+
+#define	SEP	","
+int
+proto_spec(const char *spec)
+{
+	char *s, *p, *q;
+	int ret = SSH_PROTO_UNKNOWN;
+
+	if (spec == NULL)
+		return ret;
+	q = s = xstrdup(spec);
+	for ((p = strsep(&q, SEP)); p && *p != '\0'; (p = strsep(&q, SEP))) {
+		switch (atoi(p)) {
+		case 1:
+			if (ret == SSH_PROTO_UNKNOWN)
+				ret |= SSH_PROTO_1_PREFERRED;
+			ret |= SSH_PROTO_1;
+			break;
+		case 2:
+			ret |= SSH_PROTO_2;
+			break;
+		default:
+			logit("ignoring bad proto spec: '%s'.", p);
+			break;
+		}
+	}
+	xfree(s);
+	return ret;
+}
+
+char *
+compat_cipher_proposal(char *cipher_prop)
+{
+	Buffer b;
+	char *orig_prop, *fix_ciphers;
+	char *cp, *tmp;
+
+	if (!(datafellows & SSH_BUG_BIGENDIANAES))
+		return(cipher_prop);
+
+	buffer_init(&b);
+	tmp = orig_prop = xstrdup(cipher_prop);
+	while ((cp = strsep(&tmp, ",")) != NULL) {
+		if (strncmp(cp, "aes", 3) != 0) {
+			if (buffer_len(&b) > 0)
+				buffer_append(&b, ",", 1);
+			buffer_append(&b, cp, strlen(cp));
+		}
+	}
+	buffer_append(&b, "\0", 1);
+	fix_ciphers = xstrdup(buffer_ptr(&b));
+	buffer_free(&b);
+	xfree(orig_prop);
+	debug2("Original cipher proposal: %s", cipher_prop);
+	debug2("Compat cipher proposal: %s", fix_ciphers);
+	if (!*fix_ciphers)
+		fatal("No available ciphers found.");
+
+	return(fix_ciphers);
+}