From 94f3898f43a7ef0c53dd50c60ce6d6f884de28e1 Mon Sep 17 00:00:00 2001
Date: Tue, 20 Aug 2024 20:17:01 +0800
Subject: [PATCH] backport-openssh-7.7p1-fips

Reference:https://src.fedoraproject.org/rpms/openssh/blob/rawhide/f/backport-openssh-7.7p1-fips.patch
Conflict:NA
---
 cipher-aes.c             |  3 +-
 dh.c                     | 41 +++++++++++++++++++++++++++
 dh.h                     |  1 +
 kex.c                    |  6 +++-
 kexgexc.c                |  5 ++++
 myproposal.h             | 33 ++++++++++++++++++++++
 readconf.c               | 16 +++++++----
 sandbox-seccomp-filter.c |  3 ++
 servconf.c               | 16 +++++++----
 ssh-keygen.c             | 17 ++++++++++-
 ssh-rsa.c                |  3 ++
 ssh.c                    |  5 ++++
 sshconnect2.c            | 61 ++++++++++++++++++++++------------------
 sshd.c                   | 19 ++++++++++---
 sshkey.c                 |  1 +
 15 files changed, 186 insertions(+), 44 deletions(-)

diff --git a/cipher-aes.c b/cipher-aes.c
index 8b10172..1a07697 100644
--- a/cipher-aes.c
+++ b/cipher-aes.c
@@ -154,7 +154,8 @@ evp_rijndael(void)
 	rijndal_cbc.do_cipher = ssh_rijndael_cbc;
 #ifndef SSH_OLD_EVP
 	rijndal_cbc.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 (&rijndal_cbc);
 }
diff --git a/dh.c b/dh.c
index ce2eb47..166cb02 100644
--- a/dh.c
+++ b/dh.c
@@ -36,6 +36,7 @@
 
 #include <openssl/bn.h>
 #include <openssl/dh.h>
+#include <openssl/fips.h>
 
 #include "dh.h"
 #include "pathnames.h"
@@ -164,6 +165,12 @@ 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 +509,38 @@ 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 --git a/dh.h b/dh.h
index c6326a3..e51e292 100644
--- a/dh.h
+++ b/dh.h
@@ -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 --git a/kex.c b/kex.c
index 36ae36c..1636f25 100644
--- a/kex.c
+++ b/kex.c
@@ -40,6 +40,7 @@
 #ifdef WITH_OPENSSL
 #include <openssl/crypto.h>
 #include <openssl/dh.h>
+#include <openssl/fips.h>
 # ifdef HAVE_EVP_KDF_CTX_NEW_ID
 # include <openssl/kdf.h>
 # endif
@@ -205,7 +206,10 @@ 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 --git a/kexgexc.c b/kexgexc.c
index e99e0cf..4c3feae 100644
--- a/kexgexc.c
+++ b/kexgexc.c
@@ -28,6 +28,7 @@
 
 #ifdef WITH_OPENSSL
 
+#include <openssl/fips.h>
 #include <sys/types.h>
 
 #include <openssl/dh.h>
@@ -115,6 +116,10 @@ input_kex_dh_gex_group(int type, u_int32_t seq, struct ssh *ssh)
 		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 --git a/myproposal.h b/myproposal.h
index ee6e9f7..ff8dfa8 100644
--- a/myproposal.h
+++ b/myproposal.h
@@ -56,6 +56,18 @@
 	"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," \
+	"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," \
@@ -77,6 +89,27 @@
 
 #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 --git a/readconf.c b/readconf.c
index bd8627c..dd22c3c 100644
--- a/readconf.c
+++ b/readconf.c
@@ -24,6 +24,7 @@
 #include <netinet/in_systm.h>
 #include <netinet/ip.h>
 #include <arpa/inet.h>
+#include <openssl/fips.h>
 
 #include <ctype.h>
 #include <errno.h>
@@ -2711,11 +2712,16 @@ 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 --git a/sandbox-seccomp-filter.c b/sandbox-seccomp-filter.c
index 139b6fb..5376800 100644
--- a/sandbox-seccomp-filter.c
+++ b/sandbox-seccomp-filter.c
@@ -230,6 +230,9 @@ static const struct sock_filter preauth_insns[] = {
 #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 --git a/servconf.c b/servconf.c
index 0dbf90c..24db0cc 100644
--- a/servconf.c
+++ b/servconf.c
@@ -26,6 +26,7 @@
 #ifdef HAVE_NET_ROUTE_H
 #include <net/route.h>
 #endif
+#include <openssl/fips.h>
 
 #include <ctype.h>
 #include <netdb.h>
@@ -230,11 +231,16 @@ 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 --git a/ssh-keygen.c b/ssh-keygen.c
index 46f4998..5c48ee0 100644
--- a/ssh-keygen.c
+++ b/ssh-keygen.c
@@ -23,6 +23,7 @@
 #include <openssl/pem.h>
 #include "openbsd-compat/openssl-compat.h"
 #endif
+#include <openssl/fips.h>
 
 #ifdef HAVE_STDINT_H
 # include <stdint.h>
@@ -207,6 +208,12 @@ type_bits_valid(int type, const char *name, u_int32_t *bitsp)
 #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)
@@ -1113,9 +1120,17 @@ 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));
diff --git a/ssh-rsa.c b/ssh-rsa.c
index 88a98fd..17662be 100644
--- a/ssh-rsa.c
+++ b/ssh-rsa.c
@@ -25,6 +25,7 @@
 #include <openssl/err.h>
 #include <openssl/core_names.h>
 #include <openssl/param_build.h>
+#include <openssl/fips.h>
 
 #include <stdarg.h>
 #include <string.h>
@@ -162,6 +163,8 @@ ssh_rsa_generate(struct sshkey *k, int bits)
 		goto out;
 
 	if (EVP_PKEY_keygen(ctx, &res) <= 0) {
+		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 --git a/ssh.c b/ssh.c
index 4caa6e1..d144a25 100644
--- a/ssh.c
+++ b/ssh.c
@@ -77,6 +77,7 @@
 #include <openssl/evp.h>
 #include <openssl/err.h>
 #endif
+#include <openssl/fips.h>
 #include "openbsd-compat/openssl-compat.h"
 #include "openbsd-compat/sys-queue.h"
 
@@ -1564,6 +1565,10 @@ 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 --git a/sshconnect2.c b/sshconnect2.c
index 1e217e4..1d72a91 100644
--- a/sshconnect2.c
+++ b/sshconnect2.c
@@ -45,6 +45,8 @@
 #include <vis.h>
 #endif
 
+#include <openssl/fips.h>
+
 #include "openbsd-compat/sys-queue.h"
 
 #include "xmalloc.h"
@@ -276,36 +278,41 @@ ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port,
 
 #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 --git a/sshd.c b/sshd.c
index 595e44a..f49e2e5 100644
--- a/sshd.c
+++ b/sshd.c
@@ -69,6 +69,7 @@
 #endif
 #include <pwd.h>
 #include <signal.h>
+#include <syslog.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -80,6 +81,7 @@
 #include <openssl/dh.h>
 #include <openssl/bn.h>
 #include <openssl/rand.h>
+#include <openssl/fips.h>
 #include "openbsd-compat/openssl-compat.h"
 #endif
 
@@ -1665,6 +1667,7 @@ main(int ac, char **av)
 	sigemptyset(&sigmask);
 	sigprocmask(SIG_SETMASK, &sigmask, NULL);
 
+	OpenSSL_add_all_algorithms();
 	/* Save argv. Duplicate so setproctitle emulation doesn't clobber it */
 	saved_argc = ac;
 	rexec_argc = ac;
@@ -2160,6 +2163,10 @@ 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.
@@ -2535,10 +2542,14 @@ 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 --git a/sshkey.c b/sshkey.c
index 1aee244..be2c399 100644
--- a/sshkey.c
+++ b/sshkey.c
@@ -34,6 +34,7 @@
 #include <openssl/evp.h>
 #include <openssl/err.h>
 #include <openssl/pem.h>
+#include <openssl/crypto.h>
 #include <openssl/core_names.h>
 #include <openssl/param_build.h>
 #endif
-- 
2.33.0

