diff -up openssh-8.6p1/cipher-ctr.c.fips openssh-8.6p1/cipher-ctr.c

--- openssh-8.6p1/cipher-ctr.c.fips	2021-04-19 16:53:02.994577324 +0200

+++ openssh-8.6p1/cipher-ctr.c	2021-04-19 16:53:03.064577862 +0200

@@ -179,7 +179,8 @@ evp_aes_128_ctr(void)

 	aes_ctr.do_cipher = ssh_aes_ctr;

 #ifndef SSH_OLD_EVP

 	aes_ctr.flags = EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH |

-	    EVP_CIPH_ALWAYS_CALL_INIT | EVP_CIPH_CUSTOM_IV;

+	    EVP_CIPH_ALWAYS_CALL_INIT | EVP_CIPH_CUSTOM_IV |

+	    EVP_CIPH_FLAG_FIPS;

 #endif

 	return (&aes_ctr);

 }

diff -up openssh-8.6p1/dh.c.fips openssh-8.6p1/dh.c

--- openssh-8.6p1/dh.c.fips	2021-04-16 05:55:25.000000000 +0200

+++ openssh-8.6p1/dh.c	2021-04-19 16:58:47.750263410 +0200

@@ -164,6 +164,12 @@ choose_dh(int min, int wantbits, int max

 	int best, bestcount, which, linenum;

 	struct dhgroup dhg;

+	if (FIPS_mode()) {

+		logit("Using arbitrary primes is not allowed in FIPS mode."

+		    " Falling back to known groups.");

+		return (dh_new_group_fallback(max));

+	}

+

 	if ((f = fopen(get_moduli_filename(), "r")) == NULL) {

 		logit("WARNING: could not open %s (%s), using fixed modulus",

 		    get_moduli_filename(), strerror(errno));

@@ -502,4 +508,38 @@ dh_estimate(int bits)

 	return 8192;

 }

+/*

+ * Compares the received DH parameters with known-good groups,

+ * which might be either from group14, group16 or group18.

+ */

+int

+dh_is_known_group(const DH *dh)

+{

+	const BIGNUM *p, *g;

+	const BIGNUM *known_p, *known_g;

+	DH *known = NULL;

+	int bits = 0, rv = 0;

+

+	DH_get0_pqg(dh, &p, NULL, &g);

+	bits = BN_num_bits(p);

+

+	if (bits <= 3072) {

+		known = dh_new_group14();

+	} else if (bits <= 6144) {

+		known = dh_new_group16();

+	} else {

+		known = dh_new_group18();

+	}

+

+	DH_get0_pqg(known, &known_p, NULL, &known_g);

+

+	if (BN_cmp(g, known_g) == 0 &&

+	    BN_cmp(p, known_p) == 0) {

+		rv = 1;

+	}

+

+	DH_free(known);

+	return rv;

+}

+

 #endif /* WITH_OPENSSL */

diff -up openssh-8.6p1/dh.h.fips openssh-8.6p1/dh.h

--- openssh-8.6p1/dh.h.fips	2021-04-19 16:53:03.064577862 +0200

+++ openssh-8.6p1/dh.h	2021-04-19 16:59:31.951616078 +0200

@@ -45,6 +45,7 @@ DH	*dh_new_group_fallback(int);

 int	 dh_gen_key(DH *, int);

 int	 dh_pub_is_valid(const DH *, const BIGNUM *);

+int	 dh_is_known_group(const DH *);

 u_int	 dh_estimate(int);

 void	 dh_set_moduli_file(const char *);

diff -up openssh-8.6p1/kex.c.fips openssh-8.6p1/kex.c

--- openssh-8.6p1/kex.c.fips	2021-04-19 16:53:03.058577815 +0200

+++ openssh-8.6p1/kex.c	2021-04-19 16:53:03.065577869 +0200

@@ -203,7 +203,10 @@ kex_names_valid(const char *names)

 	for ((p = strsep(&cp, ",")); p && *p != '\0';

 	    (p = strsep(&cp, ","))) {

 		if (kex_alg_by_name(p) == NULL) {

-			error("Unsupported KEX algorithm \"%.100s\"", p);

+			if (FIPS_mode())

+				error("\"%.100s\" is not allowed in FIPS mode", p);

+			else

+				error("Unsupported KEX algorithm \"%.100s\"", p);

 			free(s);

 			return 0;

 		}

diff -up openssh-8.6p1/kexgexc.c.fips openssh-8.6p1/kexgexc.c

--- openssh-8.6p1/kexgexc.c.fips	2021-04-16 05:55:25.000000000 +0200

+++ openssh-8.6p1/kexgexc.c	2021-04-19 16:53:03.065577869 +0200

@@ -28,6 +28,7 @@

 #ifdef WITH_OPENSSL

+#include <openssl/crypto.h>

 #include <sys/types.h>

 #include <openssl/dh.h>

@@ -115,6 +116,10 @@ input_kex_dh_gex_group(int type, u_int32

 		r = SSH_ERR_ALLOC_FAIL;

 		goto out;

 	}

+	if (FIPS_mode() && dh_is_known_group(kex->dh) == 0) {

+		r = SSH_ERR_INVALID_ARGUMENT;

+		goto out;

+	}

 	p = g = NULL; /* belong to kex->dh now */

 	/* generate and send 'e', client DH public key */

diff -up openssh-8.6p1/myproposal.h.fips openssh-8.6p1/myproposal.h

--- openssh-8.6p1/myproposal.h.fips	2021-04-16 05:55:25.000000000 +0200

+++ openssh-8.6p1/myproposal.h	2021-04-19 16:53:03.065577869 +0200

@@ -57,6 +57,19 @@

 	"rsa-sha2-512," \

 	"rsa-sha2-256"

+#define	KEX_FIPS_PK_ALG	\

+	"ecdsa-sha2-nistp256-cert-v01@openssh.com," \

+	"ecdsa-sha2-nistp384-cert-v01@openssh.com," \

+	"ecdsa-sha2-nistp521-cert-v01@openssh.com," \

+	"rsa-sha2-512-cert-v01@openssh.com," \

+	"rsa-sha2-256-cert-v01@openssh.com," \

+	"ssh-rsa-cert-v01@openssh.com," \

+	"ecdsa-sha2-nistp256," \

+	"ecdsa-sha2-nistp384," \

+	"ecdsa-sha2-nistp521," \

+	"rsa-sha2-512," \

+	"rsa-sha2-256,"

+

 #define	KEX_SERVER_ENCRYPT \

 	"chacha20-poly1305@openssh.com," \

 	"aes128-ctr,aes192-ctr,aes256-ctr," \

@@ -78,6 +92,27 @@

 #define KEX_CLIENT_MAC KEX_SERVER_MAC

+#define	KEX_FIPS_ENCRYPT \

+	"aes128-ctr,aes192-ctr,aes256-ctr," \

+	"aes128-cbc,3des-cbc," \

+	"aes192-cbc,aes256-cbc,rijndael-cbc@lysator.liu.se," \

+	"aes128-gcm@openssh.com,aes256-gcm@openssh.com"

+#define KEX_DEFAULT_KEX_FIPS		\

+	"ecdh-sha2-nistp256," \

+	"ecdh-sha2-nistp384," \

+	"ecdh-sha2-nistp521," \

+	"diffie-hellman-group-exchange-sha256," \

+	"diffie-hellman-group16-sha512," \

+	"diffie-hellman-group18-sha512," \

+	"diffie-hellman-group14-sha256"

+#define KEX_FIPS_MAC \

+	"hmac-sha1," \

+	"hmac-sha2-256," \

+	"hmac-sha2-512," \

+	"hmac-sha1-etm@openssh.com," \

+	"hmac-sha2-256-etm@openssh.com," \

+	"hmac-sha2-512-etm@openssh.com"

+

 /* Not a KEX value, but here so all the algorithm defaults are together */

 #define	SSH_ALLOWED_CA_SIGALGS	\

 	"ssh-ed25519," \

diff -up openssh-8.6p1/readconf.c.fips openssh-8.6p1/readconf.c

--- openssh-8.6p1/readconf.c.fips	2021-04-19 16:53:02.999577362 +0200

+++ openssh-8.6p1/readconf.c	2021-04-19 16:53:03.065577869 +0200

@@ -2538,11 +2538,16 @@ fill_default_options(Options * options)

 	all_key = sshkey_alg_list(0, 0, 1, ',');

 	all_sig = sshkey_alg_list(0, 1, 1, ',');

 	/* remove unsupported algos from default lists */

-	def_cipher = match_filter_allowlist(KEX_CLIENT_ENCRYPT, all_cipher);

-	def_mac = match_filter_allowlist(KEX_CLIENT_MAC, all_mac);

-	def_kex = match_filter_allowlist(KEX_CLIENT_KEX, all_kex);

-	def_key = match_filter_allowlist(KEX_DEFAULT_PK_ALG, all_key);

-	def_sig = match_filter_allowlist(SSH_ALLOWED_CA_SIGALGS, all_sig);

+	def_cipher = match_filter_allowlist((FIPS_mode() ?

+	    KEX_FIPS_ENCRYPT : KEX_CLIENT_ENCRYPT), all_cipher);

+	def_mac = match_filter_allowlist((FIPS_mode() ?

+	    KEX_FIPS_MAC : KEX_CLIENT_MAC), all_mac);

+	def_kex = match_filter_allowlist((FIPS_mode() ?

+	    KEX_DEFAULT_KEX_FIPS : KEX_CLIENT_KEX), all_kex);

+	def_key = match_filter_allowlist((FIPS_mode() ?

+	    KEX_FIPS_PK_ALG : KEX_DEFAULT_PK_ALG), all_key);

+	def_sig = match_filter_allowlist((FIPS_mode() ?

+	    KEX_FIPS_PK_ALG : SSH_ALLOWED_CA_SIGALGS), all_sig);

 #define ASSEMBLE(what, defaults, all) \

 	do { \

 		if ((r = kex_assemble_names(&options->what, \

diff -up openssh-8.6p1/sandbox-seccomp-filter.c.fips openssh-8.6p1/sandbox-seccomp-filter.c

--- openssh-8.6p1/sandbox-seccomp-filter.c.fips	2021-04-19 16:53:03.034577631 +0200

+++ openssh-8.6p1/sandbox-seccomp-filter.c	2021-04-19 16:53:03.065577869 +0200

@@ -160,6 +160,9 @@ static const struct sock_filter preauth_

 #ifdef __NR_open

 	SC_DENY(__NR_open, EACCES),

 #endif

+#ifdef __NR_socket

+	SC_DENY(__NR_socket, EACCES),

+#endif

 #ifdef __NR_openat

 	SC_DENY(__NR_openat, EACCES),

 #endif

diff -up openssh-8.6p1/servconf.c.fips openssh-8.6p1/servconf.c

--- openssh-8.6p1/servconf.c.fips	2021-04-19 16:53:03.027577577 +0200

+++ openssh-8.6p1/servconf.c	2021-04-19 16:53:03.066577877 +0200

@@ -226,11 +226,16 @@ assemble_algorithms(ServerOptions *o)

 	all_key = sshkey_alg_list(0, 0, 1, ',');

 	all_sig = sshkey_alg_list(0, 1, 1, ',');

 	/* remove unsupported algos from default lists */

-	def_cipher = match_filter_allowlist(KEX_SERVER_ENCRYPT, all_cipher);

-	def_mac = match_filter_allowlist(KEX_SERVER_MAC, all_mac);

-	def_kex = match_filter_allowlist(KEX_SERVER_KEX, all_kex);

-	def_key = match_filter_allowlist(KEX_DEFAULT_PK_ALG, all_key);

-	def_sig = match_filter_allowlist(SSH_ALLOWED_CA_SIGALGS, all_sig);

+	def_cipher = match_filter_allowlist((FIPS_mode() ?

+	    KEX_FIPS_ENCRYPT : KEX_SERVER_ENCRYPT), all_cipher);

+	def_mac = match_filter_allowlist((FIPS_mode() ?

+	    KEX_FIPS_MAC : KEX_SERVER_MAC), all_mac);

+	def_kex = match_filter_allowlist((FIPS_mode() ?

+	    KEX_DEFAULT_KEX_FIPS : KEX_SERVER_KEX), all_kex);

+	def_key = match_filter_allowlist((FIPS_mode() ?

+	    KEX_FIPS_PK_ALG : KEX_DEFAULT_PK_ALG), all_key);

+	def_sig = match_filter_allowlist((FIPS_mode() ?

+	    KEX_FIPS_PK_ALG : SSH_ALLOWED_CA_SIGALGS), all_sig);

 #define ASSEMBLE(what, defaults, all) \

 	do { \

 		if ((r = kex_assemble_names(&o->what, defaults, all)) != 0) \

diff -up openssh-8.6p1/ssh.c.fips openssh-8.6p1/ssh.c

--- openssh-8.6p1/ssh.c.fips	2021-04-19 16:53:03.038577662 +0200

+++ openssh-8.6p1/ssh.c	2021-04-19 16:53:03.066577877 +0200

@@ -77,6 +77,7 @@

 #include <openssl/evp.h>

 #include <openssl/err.h>

 #endif

+#include <openssl/crypto.h>

 #include "openbsd-compat/openssl-compat.h"

 #include "openbsd-compat/sys-queue.h"

@@ -1516,6 +1517,10 @@ main(int ac, char **av)

 		exit(0);

 	}

+	if (FIPS_mode()) {

+		debug("FIPS mode initialized");

+	}

+

 	/* Expand SecurityKeyProvider if it refers to an environment variable */

 	if (options.sk_provider != NULL && *options.sk_provider == '$' &&

 	    strlen(options.sk_provider) > 1) {

diff -up openssh-8.6p1/sshconnect2.c.fips openssh-8.6p1/sshconnect2.c

--- openssh-8.6p1/sshconnect2.c.fips	2021-04-19 16:53:03.055577792 +0200

+++ openssh-8.6p1/sshconnect2.c	2021-04-19 16:53:03.066577877 +0200

@@ -45,6 +45,8 @@

 #include <vis.h>

 #endif

+#include <openssl/crypto.h>

+

 #include "openbsd-compat/sys-queue.h"

 #include "xmalloc.h"

@@ -269,36 +271,41 @@ ssh_kex2(struct ssh *ssh, char *host, st

 #if defined(GSSAPI) && defined(WITH_OPENSSL)

 	if (options.gss_keyex) {

-		/* Add the GSSAPI mechanisms currently supported on this

-		 * client to the key exchange algorithm proposal */

-		orig = myproposal[PROPOSAL_KEX_ALGS];

-

-		if (options.gss_server_identity) {

-			gss_host = xstrdup(options.gss_server_identity);

-		} else if (options.gss_trust_dns) {

-			gss_host = remote_hostname(ssh);

-			/* Fall back to specified host if we are using proxy command

-			 * and can not use DNS on that socket */

-			if (strcmp(gss_host, "UNKNOWN") == 0) {

-				free(gss_host);

+		if (FIPS_mode()) {

+			logit("Disabling GSSAPIKeyExchange. Not usable in FIPS mode");

+			options.gss_keyex = 0;

+		} else {

+			/* Add the GSSAPI mechanisms currently supported on this

+			 * client to the key exchange algorithm proposal */

+			orig = myproposal[PROPOSAL_KEX_ALGS];

+

+			if (options.gss_server_identity) {

+				gss_host = xstrdup(options.gss_server_identity);

+			} else if (options.gss_trust_dns) {

+				gss_host = remote_hostname(ssh);

+				/* Fall back to specified host if we are using proxy command

+				 * and can not use DNS on that socket */

+				if (strcmp(gss_host, "UNKNOWN") == 0) {

+					free(gss_host);

+					gss_host = xstrdup(host);

+				}

+			} else {

 				gss_host = xstrdup(host);

 			}

-		} else {

-			gss_host = xstrdup(host);

-		}

-		gss = ssh_gssapi_client_mechanisms(gss_host,

-		    options.gss_client_identity, options.gss_kex_algorithms);

-		if (gss) {

-			debug("Offering GSSAPI proposal: %s", gss);

-			xasprintf(&myproposal[PROPOSAL_KEX_ALGS],

-			    "%s,%s", gss, orig);

-

-			/* If we've got GSSAPI algorithms, then we also support the

-			 * 'null' hostkey, as a last resort */

-			orig = myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS];

-			xasprintf(&myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS],

-			    "%s,null", orig);

+			gss = ssh_gssapi_client_mechanisms(gss_host,

+			    options.gss_client_identity, options.gss_kex_algorithms);

+			if (gss) {

+				debug("Offering GSSAPI proposal: %s", gss);

+				xasprintf(&myproposal[PROPOSAL_KEX_ALGS],

+				    "%s,%s", gss, orig);

+

+				/* If we've got GSSAPI algorithms, then we also support the

+				 * 'null' hostkey, as a last resort */

+				orig = myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS];

+				xasprintf(&myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS],

+				    "%s,null", orig);

+			}

 		}

 	}

 #endif

diff -up openssh-8.6p1/sshd.c.fips openssh-8.6p1/sshd.c

--- openssh-8.6p1/sshd.c.fips	2021-04-19 16:53:03.060577831 +0200

+++ openssh-8.6p1/sshd.c	2021-04-19 16:57:45.827769340 +0200

@@ -66,6 +66,7 @@

 #include <grp.h>

 #include <pwd.h>

 #include <signal.h>

+#include <syslog.h>

 #include <stdarg.h>

 #include <stdio.h>

 #include <stdlib.h>

@@ -77,6 +78,7 @@

 #include <openssl/dh.h>

 #include <openssl/bn.h>

 #include <openssl/rand.h>

+#include <openssl/crypto.h>

 #include "openbsd-compat/openssl-compat.h"

 #endif

@@ -1619,6 +1621,7 @@ main(int ac, char **av)

 #endif

 	__progname = ssh_get_progname(av[0]);

+	OpenSSL_add_all_algorithms();

 	/* Save argv. Duplicate so setproctitle emulation doesn't clobber it */

 	saved_argc = ac;

 	rexec_argc = ac;

@@ -2110,6 +2113,10 @@ main(int ac, char **av)

 	/* Reinitialize the log (because of the fork above). */

 	log_init(__progname, options.log_level, options.log_facility, log_stderr);

+	if (FIPS_mode()) {

+		debug("FIPS mode initialized");

+	}

+

 	/*

 	 * Chdir to the root directory so that the current disk can be

 	 * unmounted if desired.

@@ -2494,10 +2501,14 @@ do_ssh2_kex(struct ssh *ssh)

 	if (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS]) == 0)

 		orig = NULL;

-	if (options.gss_keyex)

-		gss = ssh_gssapi_server_mechanisms();

-	else

-		gss = NULL;

+	if (options.gss_keyex) {

+		if (FIPS_mode()) {

+			logit("Disabling GSSAPIKeyExchange. Not usable in FIPS mode");

+			options.gss_keyex = 0;

+		} else {

+			gss = ssh_gssapi_server_mechanisms();

+		}

+	}

 	if (gss && orig)

 		xasprintf(&newstr, "%s,%s", gss, orig);

diff -up openssh-8.6p1/sshkey.c.fips openssh-8.6p1/sshkey.c

--- openssh-8.6p1/sshkey.c.fips	2021-04-19 16:53:03.061577838 +0200

+++ openssh-8.6p1/sshkey.c	2021-04-19 16:53:03.067577885 +0200

@@ -34,6 +34,7 @@

 #include <openssl/evp.h>

 #include <openssl/err.h>

 #include <openssl/pem.h>

+#include <openssl/crypto.h>

 #endif

 #include "crypto_api.h"

@@ -57,6 +58,7 @@

 #define SSHKEY_INTERNAL

 #include "sshkey.h"

 #include "match.h"

+#include "log.h"

 #include "ssh-sk.h"

 #ifdef WITH_XMSS

@@ -1705,6 +1707,8 @@ rsa_generate_private_key(u_int bits, RSA

 	}

 	if (!BN_set_word(f4, RSA_F4) ||

 	    !RSA_generate_key_ex(private, bits, f4, NULL)) {

+			if (FIPS_mode())

+				logit_f("the key length might be unsupported by FIPS mode approved key generation method");

 		ret = SSH_ERR_LIBCRYPTO_ERROR;

 		goto out;

 	}

diff -up openssh-8.6p1/ssh-keygen.c.fips openssh-8.6p1/ssh-keygen.c

--- openssh-8.6p1/ssh-keygen.c.fips	2021-04-19 16:53:03.038577662 +0200

+++ openssh-8.6p1/ssh-keygen.c	2021-04-19 16:53:03.068577892 +0200

@@ -205,6 +205,12 @@ type_bits_valid(int type, const char *na

 #endif

 	}

 #ifdef WITH_OPENSSL

+	if (FIPS_mode()) {

+		if (type == KEY_DSA)

+			fatal("DSA keys are not allowed in FIPS mode");

+		if (type == KEY_ED25519)

+			fatal("ED25519 keys are not allowed in FIPS mode");

+	}

 	switch (type) {

 	case KEY_DSA:

 		if (*bitsp != 1024)

@@ -1098,9 +1104,17 @@ do_gen_all_hostkeys(struct passwd *pw)

 			first = 1;

 			printf("%s: generating new host keys: ", __progname);

 		}

+		type = sshkey_type_from_name(key_types[i].key_type);

+

+		/* Skip the keys that are not supported in FIPS mode */

+		if (FIPS_mode() && (type == KEY_DSA || type == KEY_ED25519)) {

+			logit("Skipping %s key in FIPS mode",

+			    key_types[i].key_type_display);

+			goto next;

+		}

+

 		printf("%s ", key_types[i].key_type_display);

 		fflush(stdout);

-		type = sshkey_type_from_name(key_types[i].key_type);

 		if ((fd = mkstemp(prv_tmp)) == -1) {

 			error("Could not save your private key in %s: %s",

 			    prv_tmp, strerror(errno));