Adding upstream version 1:9.2p1.upstream/1%9.2p1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 391 insertions, 0 deletions

diff --git a/ssh-pkcs11-client.c b/ssh-pkcs11-client.c
new file mode 100644
index 0000000..cfd833d
--- /dev/null
+++ b/ssh-pkcs11-client.c
@@ -0,0 +1,391 @@
+/* $OpenBSD: ssh-pkcs11-client.c,v 1.17 2020/10/18 11:32:02 djm Exp $ */
+/*
+ * Copyright (c) 2010 Markus Friedl.  All rights reserved.
+ * Copyright (c) 2014 Pedro Martelletto. All rights reserved.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "includes.h"
+
+#ifdef ENABLE_PKCS11
+
+#include <sys/types.h>
+#ifdef HAVE_SYS_TIME_H
+# include <sys/time.h>
+#endif
+#include <sys/socket.h>
+
+#include <stdarg.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include <openssl/ecdsa.h>
+#include <openssl/rsa.h>
+
+#include "openbsd-compat/openssl-compat.h"
+
+#include "pathnames.h"
+#include "xmalloc.h"
+#include "sshbuf.h"
+#include "log.h"
+#include "misc.h"
+#include "sshkey.h"
+#include "authfd.h"
+#include "atomicio.h"
+#include "ssh-pkcs11.h"
+#include "ssherr.h"
+
+/* borrows code from sftp-server and ssh-agent */
+
+static int fd = -1;
+static pid_t pid = -1;
+
+static void
+send_msg(struct sshbuf *m)
+{
+	u_char buf[4];
+	size_t mlen = sshbuf_len(m);
+	int r;
+
+	POKE_U32(buf, mlen);
+	if (atomicio(vwrite, fd, buf, 4) != 4 ||
+	    atomicio(vwrite, fd, sshbuf_mutable_ptr(m),
+	    sshbuf_len(m)) != sshbuf_len(m))
+		error("write to helper failed");
+	if ((r = sshbuf_consume(m, mlen)) != 0)
+		fatal_fr(r, "consume");
+}
+
+static int
+recv_msg(struct sshbuf *m)
+{
+	u_int l, len;
+	u_char c, buf[1024];
+	int r;
+
+	if ((len = atomicio(read, fd, buf, 4)) != 4) {
+		error("read from helper failed: %u", len);
+		return (0); /* XXX */
+	}
+	len = PEEK_U32(buf);
+	if (len > 256 * 1024)
+		fatal("response too long: %u", len);
+	/* read len bytes into m */
+	sshbuf_reset(m);
+	while (len > 0) {
+		l = len;
+		if (l > sizeof(buf))
+			l = sizeof(buf);
+		if (atomicio(read, fd, buf, l) != l) {
+			error("response from helper failed.");
+			return (0); /* XXX */
+		}
+		if ((r = sshbuf_put(m, buf, l)) != 0)
+			fatal_fr(r, "sshbuf_put");
+		len -= l;
+	}
+	if ((r = sshbuf_get_u8(m, &c)) != 0)
+		fatal_fr(r, "parse type");
+	return c;
+}
+
+int
+pkcs11_init(int interactive)
+{
+	return (0);
+}
+
+void
+pkcs11_terminate(void)
+{
+	if (fd >= 0)
+		close(fd);
+}
+
+static int
+rsa_encrypt(int flen, const u_char *from, u_char *to, RSA *rsa, int padding)
+{
+	struct sshkey *key = NULL;
+	struct sshbuf *msg = NULL;
+	u_char *blob = NULL, *signature = NULL;
+	size_t blen, slen = 0;
+	int r, ret = -1;
+
+	if (padding != RSA_PKCS1_PADDING)
+		goto fail;
+	key = sshkey_new(KEY_UNSPEC);
+	if (key == NULL) {
+		error_f("sshkey_new failed");
+		goto fail;
+	}
+	key->type = KEY_RSA;
+	RSA_up_ref(rsa);
+	key->rsa = rsa;
+	if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) {
+		error_fr(r, "encode key");
+		goto fail;
+	}
+	if ((msg = sshbuf_new()) == NULL)
+		fatal_f("sshbuf_new failed");
+	if ((r = sshbuf_put_u8(msg, SSH2_AGENTC_SIGN_REQUEST)) != 0 ||
+	    (r = sshbuf_put_string(msg, blob, blen)) != 0 ||
+	    (r = sshbuf_put_string(msg, from, flen)) != 0 ||
+	    (r = sshbuf_put_u32(msg, 0)) != 0)
+		fatal_fr(r, "compose");
+	send_msg(msg);
+	sshbuf_reset(msg);
+
+	if (recv_msg(msg) == SSH2_AGENT_SIGN_RESPONSE) {
+		if ((r = sshbuf_get_string(msg, &signature, &slen)) != 0)
+			fatal_fr(r, "parse");
+		if (slen <= (size_t)RSA_size(rsa)) {
+			memcpy(to, signature, slen);
+			ret = slen;
+		}
+		free(signature);
+	}
+ fail:
+	free(blob);
+	sshkey_free(key);
+	sshbuf_free(msg);
+	return (ret);
+}
+
+#if defined(OPENSSL_HAS_ECC) && defined(HAVE_EC_KEY_METHOD_NEW)
+static ECDSA_SIG *
+ecdsa_do_sign(const unsigned char *dgst, int dgst_len, const BIGNUM *inv,
+    const BIGNUM *rp, EC_KEY *ec)
+{
+	struct sshkey *key = NULL;
+	struct sshbuf *msg = NULL;
+	ECDSA_SIG *ret = NULL;
+	const u_char *cp;
+	u_char *blob = NULL, *signature = NULL;
+	size_t blen, slen = 0;
+	int r, nid;
+
+	nid = sshkey_ecdsa_key_to_nid(ec);
+	if (nid < 0) {
+		error_f("couldn't get curve nid");
+		goto fail;
+	}
+
+	key = sshkey_new(KEY_UNSPEC);
+	if (key == NULL) {
+		error_f("sshkey_new failed");
+		goto fail;
+	}
+	key->ecdsa = ec;
+	key->ecdsa_nid = nid;
+	key->type = KEY_ECDSA;
+	EC_KEY_up_ref(ec);
+
+	if ((r = sshkey_to_blob(key, &blob, &blen)) != 0) {
+		error_fr(r, "encode key");
+		goto fail;
+	}
+	if ((msg = sshbuf_new()) == NULL)
+		fatal_f("sshbuf_new failed");
+	if ((r = sshbuf_put_u8(msg, SSH2_AGENTC_SIGN_REQUEST)) != 0 ||
+	    (r = sshbuf_put_string(msg, blob, blen)) != 0 ||
+	    (r = sshbuf_put_string(msg, dgst, dgst_len)) != 0 ||
+	    (r = sshbuf_put_u32(msg, 0)) != 0)
+		fatal_fr(r, "compose");
+	send_msg(msg);
+	sshbuf_reset(msg);
+
+	if (recv_msg(msg) == SSH2_AGENT_SIGN_RESPONSE) {
+		if ((r = sshbuf_get_string(msg, &signature, &slen)) != 0)
+			fatal_fr(r, "parse");
+		cp = signature;
+		ret = d2i_ECDSA_SIG(NULL, &cp, slen);
+		free(signature);
+	}
+
+ fail:
+	free(blob);
+	sshkey_free(key);
+	sshbuf_free(msg);
+	return (ret);
+}
+#endif /* OPENSSL_HAS_ECC && HAVE_EC_KEY_METHOD_NEW */
+
+static RSA_METHOD	*helper_rsa;
+#if defined(OPENSSL_HAS_ECC) && defined(HAVE_EC_KEY_METHOD_NEW)
+static EC_KEY_METHOD	*helper_ecdsa;
+#endif /* OPENSSL_HAS_ECC && HAVE_EC_KEY_METHOD_NEW */
+
+/* redirect private key crypto operations to the ssh-pkcs11-helper */
+static void
+wrap_key(struct sshkey *k)
+{
+	if (k->type == KEY_RSA)
+		RSA_set_method(k->rsa, helper_rsa);
+#if defined(OPENSSL_HAS_ECC) && defined(HAVE_EC_KEY_METHOD_NEW)
+	else if (k->type == KEY_ECDSA)
+		EC_KEY_set_method(k->ecdsa, helper_ecdsa);
+#endif /* OPENSSL_HAS_ECC && HAVE_EC_KEY_METHOD_NEW */
+	else
+		fatal_f("unknown key type");
+}
+
+static int
+pkcs11_start_helper_methods(void)
+{
+	if (helper_rsa != NULL)
+		return (0);
+
+#if defined(OPENSSL_HAS_ECC) && defined(HAVE_EC_KEY_METHOD_NEW)
+	int (*orig_sign)(int, const unsigned char *, int, unsigned char *,
+	    unsigned int *, const BIGNUM *, const BIGNUM *, EC_KEY *) = NULL;
+	if (helper_ecdsa != NULL)
+		return (0);
+	helper_ecdsa = EC_KEY_METHOD_new(EC_KEY_OpenSSL());
+	if (helper_ecdsa == NULL)
+		return (-1);
+	EC_KEY_METHOD_get_sign(helper_ecdsa, &orig_sign, NULL, NULL);
+	EC_KEY_METHOD_set_sign(helper_ecdsa, orig_sign, NULL, ecdsa_do_sign);
+#endif /* OPENSSL_HAS_ECC && HAVE_EC_KEY_METHOD_NEW */
+
+	if ((helper_rsa = RSA_meth_dup(RSA_get_default_method())) == NULL)
+		fatal_f("RSA_meth_dup failed");
+	if (!RSA_meth_set1_name(helper_rsa, "ssh-pkcs11-helper") ||
+	    !RSA_meth_set_priv_enc(helper_rsa, rsa_encrypt))
+		fatal_f("failed to prepare method");
+
+	return (0);
+}
+
+static int
+pkcs11_start_helper(void)
+{
+	int pair[2];
+	char *helper, *verbosity = NULL;
+
+	if (log_level_get() >= SYSLOG_LEVEL_DEBUG1)
+		verbosity = "-vvv";
+
+	if (pkcs11_start_helper_methods() == -1) {
+		error("pkcs11_start_helper_methods failed");
+		return (-1);
+	}
+
+	if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1) {
+		error("socketpair: %s", strerror(errno));
+		return (-1);
+	}
+	if ((pid = fork()) == -1) {
+		error("fork: %s", strerror(errno));
+		return (-1);
+	} else if (pid == 0) {
+		if ((dup2(pair[1], STDIN_FILENO) == -1) ||
+		    (dup2(pair[1], STDOUT_FILENO) == -1)) {
+			fprintf(stderr, "dup2: %s\n", strerror(errno));
+			_exit(1);
+		}
+		close(pair[0]);
+		close(pair[1]);
+		helper = getenv("SSH_PKCS11_HELPER");
+		if (helper == NULL || strlen(helper) == 0)
+			helper = _PATH_SSH_PKCS11_HELPER;
+		debug_f("starting %s %s", helper,
+		    verbosity == NULL ? "" : verbosity);
+		execlp(helper, helper, verbosity, (char *)NULL);
+		fprintf(stderr, "exec: %s: %s\n", helper, strerror(errno));
+		_exit(1);
+	}
+	close(pair[1]);
+	fd = pair[0];
+	return (0);
+}
+
+int
+pkcs11_add_provider(char *name, char *pin, struct sshkey ***keysp,
+    char ***labelsp)
+{
+	struct sshkey *k;
+	int r, type;
+	u_char *blob;
+	char *label;
+	size_t blen;
+	u_int nkeys, i;
+	struct sshbuf *msg;
+
+	if (fd < 0 && pkcs11_start_helper() < 0)
+		return (-1);
+
+	if ((msg = sshbuf_new()) == NULL)
+		fatal_f("sshbuf_new failed");
+	if ((r = sshbuf_put_u8(msg, SSH_AGENTC_ADD_SMARTCARD_KEY)) != 0 ||
+	    (r = sshbuf_put_cstring(msg, name)) != 0 ||
+	    (r = sshbuf_put_cstring(msg, pin)) != 0)
+		fatal_fr(r, "compose");
+	send_msg(msg);
+	sshbuf_reset(msg);
+
+	type = recv_msg(msg);
+	if (type == SSH2_AGENT_IDENTITIES_ANSWER) {
+		if ((r = sshbuf_get_u32(msg, &nkeys)) != 0)
+			fatal_fr(r, "parse nkeys");
+		*keysp = xcalloc(nkeys, sizeof(struct sshkey *));
+		if (labelsp)
+			*labelsp = xcalloc(nkeys, sizeof(char *));
+		for (i = 0; i < nkeys; i++) {
+			/* XXX clean up properly instead of fatal() */
+			if ((r = sshbuf_get_string(msg, &blob, &blen)) != 0 ||
+			    (r = sshbuf_get_cstring(msg, &label, NULL)) != 0)
+				fatal_fr(r, "parse key");
+			if ((r = sshkey_from_blob(blob, blen, &k)) != 0)
+				fatal_fr(r, "decode key");
+			wrap_key(k);
+			(*keysp)[i] = k;
+			if (labelsp)
+				(*labelsp)[i] = label;
+			else
+				free(label);
+			free(blob);
+		}
+	} else if (type == SSH2_AGENT_FAILURE) {
+		if ((r = sshbuf_get_u32(msg, &nkeys)) != 0)
+			nkeys = -1;
+	} else {
+		nkeys = -1;
+	}
+	sshbuf_free(msg);
+	return (nkeys);
+}
+
+int
+pkcs11_del_provider(char *name)
+{
+	int r, ret = -1;
+	struct sshbuf *msg;
+
+	if ((msg = sshbuf_new()) == NULL)
+		fatal_f("sshbuf_new failed");
+	if ((r = sshbuf_put_u8(msg, SSH_AGENTC_REMOVE_SMARTCARD_KEY)) != 0 ||
+	    (r = sshbuf_put_cstring(msg, name)) != 0 ||
+	    (r = sshbuf_put_cstring(msg, "")) != 0)
+		fatal_fr(r, "compose");
+	send_msg(msg);
+	sshbuf_reset(msg);
+
+	if (recv_msg(msg) == SSH_AGENT_SUCCESS)
+		ret = 0;
+	sshbuf_free(msg);
+	return (ret);
+}
+
+#endif /* ENABLE_PKCS11 */