Adding upstream version 1:8.4p1.upstream/1%8.4p1upstream

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

1 files changed, 456 insertions, 0 deletions

diff --git a/ssh-pkcs11-helper.c b/ssh-pkcs11-helper.c
new file mode 100644
index 0000000..d73e835
--- /dev/null
+++ b/ssh-pkcs11-helper.c
@@ -0,0 +1,456 @@
+/* $OpenBSD: ssh-pkcs11-helper.c,v 1.23 2020/03/06 18:26:21 markus Exp $ */
+/*
+ * Copyright (c) 2010 Markus Friedl.  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"
+
+#include <sys/types.h>
+#ifdef HAVE_SYS_TIME_H
+# include <sys/time.h>
+#endif
+
+#include "openbsd-compat/sys-queue.h"
+
+#include <stdlib.h>
+#include <errno.h>
+#ifdef HAVE_POLL_H
+#include <poll.h>
+#endif
+#include <stdarg.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "xmalloc.h"
+#include "sshbuf.h"
+#include "log.h"
+#include "misc.h"
+#include "sshkey.h"
+#include "authfd.h"
+#include "ssh-pkcs11.h"
+#include "ssherr.h"
+
+#ifdef ENABLE_PKCS11
+
+#ifdef WITH_OPENSSL
+
+/* borrows code from sftp-server and ssh-agent */
+
+struct pkcs11_keyinfo {
+	struct sshkey	*key;
+	char		*providername, *label;
+	TAILQ_ENTRY(pkcs11_keyinfo) next;
+};
+
+TAILQ_HEAD(, pkcs11_keyinfo) pkcs11_keylist;
+
+#define MAX_MSG_LENGTH		10240 /*XXX*/
+
+/* input and output queue */
+struct sshbuf *iqueue;
+struct sshbuf *oqueue;
+
+static void
+add_key(struct sshkey *k, char *name, char *label)
+{
+	struct pkcs11_keyinfo *ki;
+
+	ki = xcalloc(1, sizeof(*ki));
+	ki->providername = xstrdup(name);
+	ki->key = k;
+	ki->label = xstrdup(label);
+	TAILQ_INSERT_TAIL(&pkcs11_keylist, ki, next);
+}
+
+static void
+del_keys_by_name(char *name)
+{
+	struct pkcs11_keyinfo *ki, *nxt;
+
+	for (ki = TAILQ_FIRST(&pkcs11_keylist); ki; ki = nxt) {
+		nxt = TAILQ_NEXT(ki, next);
+		if (!strcmp(ki->providername, name)) {
+			TAILQ_REMOVE(&pkcs11_keylist, ki, next);
+			free(ki->providername);
+			free(ki->label);
+			sshkey_free(ki->key);
+			free(ki);
+		}
+	}
+}
+
+/* lookup matching 'private' key */
+static struct sshkey *
+lookup_key(struct sshkey *k)
+{
+	struct pkcs11_keyinfo *ki;
+
+	TAILQ_FOREACH(ki, &pkcs11_keylist, next) {
+		debug("check %p %s %s", ki, ki->providername, ki->label);
+		if (sshkey_equal(k, ki->key))
+			return (ki->key);
+	}
+	return (NULL);
+}
+
+static void
+send_msg(struct sshbuf *m)
+{
+	int r;
+
+	if ((r = sshbuf_put_stringb(oqueue, m)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+}
+
+static void
+process_add(void)
+{
+	char *name, *pin;
+	struct sshkey **keys = NULL;
+	int r, i, nkeys;
+	u_char *blob;
+	size_t blen;
+	struct sshbuf *msg;
+	char **labels = NULL;
+
+	if ((msg = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0 ||
+	    (r = sshbuf_get_cstring(iqueue, &pin, NULL)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	if ((nkeys = pkcs11_add_provider(name, pin, &keys, &labels)) > 0) {
+		if ((r = sshbuf_put_u8(msg,
+		    SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
+		    (r = sshbuf_put_u32(msg, nkeys)) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+		for (i = 0; i < nkeys; i++) {
+			if ((r = sshkey_to_blob(keys[i], &blob, &blen)) != 0) {
+				debug("%s: sshkey_to_blob: %s",
+				    __func__, ssh_err(r));
+				continue;
+			}
+			if ((r = sshbuf_put_string(msg, blob, blen)) != 0 ||
+			    (r = sshbuf_put_cstring(msg, labels[i])) != 0)
+				fatal("%s: buffer error: %s",
+				    __func__, ssh_err(r));
+			free(blob);
+			add_key(keys[i], name, labels[i]);
+			free(labels[i]);
+		}
+	} else {
+		if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+		if ((r = sshbuf_put_u32(msg, -nkeys)) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	}
+	free(labels);
+	free(keys); /* keys themselves are transferred to pkcs11_keylist */
+	free(pin);
+	free(name);
+	send_msg(msg);
+	sshbuf_free(msg);
+}
+
+static void
+process_del(void)
+{
+	char *name, *pin;
+	struct sshbuf *msg;
+	int r;
+
+	if ((msg = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((r = sshbuf_get_cstring(iqueue, &name, NULL)) != 0 ||
+	    (r = sshbuf_get_cstring(iqueue, &pin, NULL)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	del_keys_by_name(name);
+	if ((r = sshbuf_put_u8(msg, pkcs11_del_provider(name) == 0 ?
+	    SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	free(pin);
+	free(name);
+	send_msg(msg);
+	sshbuf_free(msg);
+}
+
+static void
+process_sign(void)
+{
+	u_char *blob, *data, *signature = NULL;
+	size_t blen, dlen, slen = 0;
+	int r, ok = -1;
+	struct sshkey *key, *found;
+	struct sshbuf *msg;
+
+	/* XXX support SHA2 signature flags */
+	if ((r = sshbuf_get_string(iqueue, &blob, &blen)) != 0 ||
+	    (r = sshbuf_get_string(iqueue, &data, &dlen)) != 0 ||
+	    (r = sshbuf_get_u32(iqueue, NULL)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+	if ((r = sshkey_from_blob(blob, blen, &key)) != 0)
+		error("%s: sshkey_from_blob: %s", __func__, ssh_err(r));
+	else {
+		if ((found = lookup_key(key)) != NULL) {
+#ifdef WITH_OPENSSL
+			int ret;
+
+			if (key->type == KEY_RSA) {
+				slen = RSA_size(key->rsa);
+				signature = xmalloc(slen);
+				ret = RSA_private_encrypt(dlen, data, signature,
+				    found->rsa, RSA_PKCS1_PADDING);
+				if (ret != -1) {
+					slen = ret;
+					ok = 0;
+				}
+#ifdef OPENSSL_HAS_ECC
+			} else if (key->type == KEY_ECDSA) {
+				u_int xslen = ECDSA_size(key->ecdsa);
+
+				signature = xmalloc(xslen);
+				/* "The parameter type is ignored." */
+				ret = ECDSA_sign(-1, data, dlen, signature,
+				    &xslen, found->ecdsa);
+				if (ret != 0)
+					ok = 0;
+				else
+					error("%s: ECDSA_sign"
+					    " returns %d", __func__, ret);
+				slen = xslen;
+#endif /* OPENSSL_HAS_ECC */
+			} else
+				error("%s: don't know how to sign with key "
+				    "type %d", __func__, (int)key->type);
+#endif /* WITH_OPENSSL */
+		}
+		sshkey_free(key);
+	}
+	if ((msg = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if (ok == 0) {
+		if ((r = sshbuf_put_u8(msg, SSH2_AGENT_SIGN_RESPONSE)) != 0 ||
+		    (r = sshbuf_put_string(msg, signature, slen)) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	} else {
+		if ((r = sshbuf_put_u8(msg, SSH2_AGENT_FAILURE)) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	}
+	free(data);
+	free(blob);
+	free(signature);
+	send_msg(msg);
+	sshbuf_free(msg);
+}
+
+static void
+process(void)
+{
+	u_int msg_len;
+	u_int buf_len;
+	u_int consumed;
+	u_char type;
+	const u_char *cp;
+	int r;
+
+	buf_len = sshbuf_len(iqueue);
+	if (buf_len < 5)
+		return;		/* Incomplete message. */
+	cp = sshbuf_ptr(iqueue);
+	msg_len = get_u32(cp);
+	if (msg_len > MAX_MSG_LENGTH) {
+		error("bad message len %d", msg_len);
+		cleanup_exit(11);
+	}
+	if (buf_len < msg_len + 4)
+		return;
+	if ((r = sshbuf_consume(iqueue, 4)) != 0 ||
+	    (r = sshbuf_get_u8(iqueue, &type)) != 0)
+		fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	buf_len -= 4;
+	switch (type) {
+	case SSH_AGENTC_ADD_SMARTCARD_KEY:
+		debug("process_add");
+		process_add();
+		break;
+	case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
+		debug("process_del");
+		process_del();
+		break;
+	case SSH2_AGENTC_SIGN_REQUEST:
+		debug("process_sign");
+		process_sign();
+		break;
+	default:
+		error("Unknown message %d", type);
+		break;
+	}
+	/* discard the remaining bytes from the current packet */
+	if (buf_len < sshbuf_len(iqueue)) {
+		error("iqueue grew unexpectedly");
+		cleanup_exit(255);
+	}
+	consumed = buf_len - sshbuf_len(iqueue);
+	if (msg_len < consumed) {
+		error("msg_len %d < consumed %d", msg_len, consumed);
+		cleanup_exit(255);
+	}
+	if (msg_len > consumed) {
+		if ((r = sshbuf_consume(iqueue, msg_len - consumed)) != 0)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	}
+}
+
+void
+cleanup_exit(int i)
+{
+	/* XXX */
+	_exit(i);
+}
+
+
+int
+main(int argc, char **argv)
+{
+	int r, ch, in, out, log_stderr = 0;
+	ssize_t len;
+	SyslogFacility log_facility = SYSLOG_FACILITY_AUTH;
+	LogLevel log_level = SYSLOG_LEVEL_ERROR;
+	char buf[4*4096];
+	extern char *__progname;
+	struct pollfd pfd[2];
+
+	__progname = ssh_get_progname(argv[0]);
+	seed_rng();
+	TAILQ_INIT(&pkcs11_keylist);
+
+	log_init(__progname, log_level, log_facility, log_stderr);
+
+	while ((ch = getopt(argc, argv, "v")) != -1) {
+		switch (ch) {
+		case 'v':
+			log_stderr = 1;
+			if (log_level == SYSLOG_LEVEL_ERROR)
+				log_level = SYSLOG_LEVEL_DEBUG1;
+			else if (log_level < SYSLOG_LEVEL_DEBUG3)
+				log_level++;
+			break;
+		default:
+			fprintf(stderr, "usage: %s [-v]\n", __progname);
+			exit(1);
+		}
+	}
+
+	log_init(__progname, log_level, log_facility, log_stderr);
+
+	pkcs11_init(0);
+
+	in = STDIN_FILENO;
+	out = STDOUT_FILENO;
+
+	if ((iqueue = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+	if ((oqueue = sshbuf_new()) == NULL)
+		fatal("%s: sshbuf_new failed", __func__);
+
+	while (1) {
+		memset(pfd, 0, sizeof(pfd));
+		pfd[0].fd = in;
+		pfd[1].fd = out;
+
+		/*
+		 * Ensure that we can read a full buffer and handle
+		 * the worst-case length packet it can generate,
+		 * otherwise apply backpressure by stopping reads.
+		 */
+		if ((r = sshbuf_check_reserve(iqueue, sizeof(buf))) == 0 &&
+		    (r = sshbuf_check_reserve(oqueue, MAX_MSG_LENGTH)) == 0)
+			pfd[0].events = POLLIN;
+		else if (r != SSH_ERR_NO_BUFFER_SPACE)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+
+		if (sshbuf_len(oqueue) > 0)
+			pfd[1].events = POLLOUT;
+
+		if ((r = poll(pfd, 2, -1 /* INFTIM */)) <= 0) {
+			if (r == 0 || errno == EINTR)
+				continue;
+			fatal("poll: %s", strerror(errno));
+		}
+
+		/* copy stdin to iqueue */
+		if ((pfd[0].revents & (POLLIN|POLLERR)) != 0) {
+			len = read(in, buf, sizeof buf);
+			if (len == 0) {
+				debug("read eof");
+				cleanup_exit(0);
+			} else if (len < 0) {
+				error("read: %s", strerror(errno));
+				cleanup_exit(1);
+			} else if ((r = sshbuf_put(iqueue, buf, len)) != 0) {
+				fatal("%s: buffer error: %s",
+				    __func__, ssh_err(r));
+			}
+		}
+		/* send oqueue to stdout */
+		if ((pfd[1].revents & (POLLOUT|POLLHUP)) != 0) {
+			len = write(out, sshbuf_ptr(oqueue),
+			    sshbuf_len(oqueue));
+			if (len < 0) {
+				error("write: %s", strerror(errno));
+				cleanup_exit(1);
+			} else if ((r = sshbuf_consume(oqueue, len)) != 0) {
+				fatal("%s: buffer error: %s",
+				    __func__, ssh_err(r));
+			}
+		}
+
+		/*
+		 * Process requests from client if we can fit the results
+		 * into the output buffer, otherwise stop processing input
+		 * and let the output queue drain.
+		 */
+		if ((r = sshbuf_check_reserve(oqueue, MAX_MSG_LENGTH)) == 0)
+			process();
+		else if (r != SSH_ERR_NO_BUFFER_SPACE)
+			fatal("%s: buffer error: %s", __func__, ssh_err(r));
+	}
+}
+
+#else /* WITH_OPENSSL */
+void
+cleanup_exit(int i)
+{
+	_exit(i);
+}
+
+int
+main(int argc, char **argv)
+{
+	fprintf(stderr, "PKCS#11 code is not enabled\n");
+	return 1;
+}
+#endif /* WITH_OPENSSL */
+#else /* ENABLE_PKCS11 */
+int
+main(int argc, char **argv)
+{
+	extern char *__progname;
+
+	__progname = ssh_get_progname(argv[0]);
+	log_init(__progname, SYSLOG_LEVEL_ERROR, SYSLOG_FACILITY_AUTH, 0);
+	fatal("PKCS#11 support disabled at compile time");
+}
+#endif /* ENABLE_PKCS11 */