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authorAlistair Delva <adelva@google.com>2020-08-21 00:00:13 +0000
committerGerrit Code Review <noreply-gerritcodereview@google.com>2020-08-21 00:00:13 +0000
commited358b3546c776c1c677fd88eb8f716cf6187510 (patch)
tree3c6134bcb2cda4b9dccc57b4a8b997a945aab62d /ssh-pkcs11-helper.c
parent22246b08952d746a7cc5a292570636cf4277598f (diff)
parent44a1065de8a58c51a021243a28bfa01e87822e4f (diff)
Merge changes I934c73d4,I28cdc9a0,I9e734da9,I3c079d86
* changes: UPSTREAM: depend UPSTREAM: upstream: avoid possible NULL deref; from Pedro Martelletto Revert "upstream: fix compilation with DEBUG_KEXDH; bz#3160 ok dtucker@" Merge upstream-master into master
Diffstat (limited to 'ssh-pkcs11-helper.c')
-rw-r--r--ssh-pkcs11-helper.c336
1 files changed, 209 insertions, 127 deletions
diff --git a/ssh-pkcs11-helper.c b/ssh-pkcs11-helper.c
index ceabc8ba..d73e8357 100644
--- a/ssh-pkcs11-helper.c
+++ b/ssh-pkcs11-helper.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh-pkcs11-helper.c,v 1.10 2015/01/20 23:14:00 deraadt Exp $ */
+/* $OpenBSD: ssh-pkcs11-helper.c,v 1.23 2020/03/06 18:26:21 markus Exp $ */
/*
* Copyright (c) 2010 Markus Friedl. All rights reserved.
*
@@ -24,26 +24,33 @@
#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 <errno.h>
#include "xmalloc.h"
-#include "buffer.h"
+#include "sshbuf.h"
#include "log.h"
#include "misc.h"
-#include "key.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 {
- Key *key;
- char *providername;
+ struct sshkey *key;
+ char *providername, *label;
TAILQ_ENTRY(pkcs11_keyinfo) next;
};
@@ -51,22 +58,19 @@ TAILQ_HEAD(, pkcs11_keyinfo) pkcs11_keylist;
#define MAX_MSG_LENGTH 10240 /*XXX*/
-/* helper */
-#define get_int() buffer_get_int(&iqueue);
-#define get_string(lenp) buffer_get_string(&iqueue, lenp);
-
/* input and output queue */
-Buffer iqueue;
-Buffer oqueue;
+struct sshbuf *iqueue;
+struct sshbuf *oqueue;
static void
-add_key(Key *k, char *name)
+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);
}
@@ -80,131 +84,175 @@ del_keys_by_name(char *name)
if (!strcmp(ki->providername, name)) {
TAILQ_REMOVE(&pkcs11_keylist, ki, next);
free(ki->providername);
- key_free(ki->key);
+ free(ki->label);
+ sshkey_free(ki->key);
free(ki);
}
}
}
/* lookup matching 'private' key */
-static Key *
-lookup_key(Key *k)
+static struct sshkey *
+lookup_key(struct sshkey *k)
{
struct pkcs11_keyinfo *ki;
TAILQ_FOREACH(ki, &pkcs11_keylist, next) {
- debug("check %p %s", ki, ki->providername);
- if (key_equal(k, ki->key))
+ 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(Buffer *m)
+send_msg(struct sshbuf *m)
{
- int mlen = buffer_len(m);
+ int r;
- buffer_put_int(&oqueue, mlen);
- buffer_append(&oqueue, buffer_ptr(m), mlen);
- buffer_consume(m, mlen);
+ 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;
- Key **keys;
- int i, nkeys;
+ struct sshkey **keys = NULL;
+ int r, i, nkeys;
u_char *blob;
- u_int blen;
- Buffer msg;
-
- buffer_init(&msg);
- name = get_string(NULL);
- pin = get_string(NULL);
- if ((nkeys = pkcs11_add_provider(name, pin, &keys)) > 0) {
- buffer_put_char(&msg, SSH2_AGENT_IDENTITIES_ANSWER);
- buffer_put_int(&msg, nkeys);
+ 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 (key_to_blob(keys[i], &blob, &blen) == 0)
+ if ((r = sshkey_to_blob(keys[i], &blob, &blen)) != 0) {
+ debug("%s: sshkey_to_blob: %s",
+ __func__, ssh_err(r));
continue;
- buffer_put_string(&msg, blob, blen);
- buffer_put_cstring(&msg, name);
+ }
+ 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);
+ add_key(keys[i], name, labels[i]);
+ free(labels[i]);
}
- free(keys);
} else {
- buffer_put_char(&msg, SSH_AGENT_FAILURE);
+ 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);
- buffer_free(&msg);
+ send_msg(msg);
+ sshbuf_free(msg);
}
static void
process_del(void)
{
char *name, *pin;
- Buffer msg;
-
- buffer_init(&msg);
- name = get_string(NULL);
- pin = get_string(NULL);
+ 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 (pkcs11_del_provider(name) == 0)
- buffer_put_char(&msg, SSH_AGENT_SUCCESS);
- else
- buffer_put_char(&msg, SSH_AGENT_FAILURE);
+ 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);
- buffer_free(&msg);
+ send_msg(msg);
+ sshbuf_free(msg);
}
static void
process_sign(void)
{
u_char *blob, *data, *signature = NULL;
- u_int blen, dlen, slen = 0;
- int ok = -1;
- Key *key, *found;
- Buffer msg;
-
- blob = get_string(&blen);
- data = get_string(&dlen);
- (void)get_int(); /* XXX ignore flags */
-
- if ((key = key_from_blob(blob, blen)) != 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;
- slen = RSA_size(key->rsa);
- signature = xmalloc(slen);
- if ((ret = RSA_private_encrypt(dlen, data, signature,
- found->rsa, RSA_PKCS1_PADDING)) != -1) {
- slen = ret;
- ok = 0;
- }
+ 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 */
}
- key_free(key);
+ sshkey_free(key);
}
- buffer_init(&msg);
+ if ((msg = sshbuf_new()) == NULL)
+ fatal("%s: sshbuf_new failed", __func__);
if (ok == 0) {
- buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
- buffer_put_string(&msg, signature, slen);
+ 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 {
- buffer_put_char(&msg, SSH_AGENT_FAILURE);
+ 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);
- buffer_free(&msg);
+ send_msg(msg);
+ sshbuf_free(msg);
}
static void
@@ -213,13 +261,14 @@ process(void)
u_int msg_len;
u_int buf_len;
u_int consumed;
- u_int type;
- u_char *cp;
+ u_char type;
+ const u_char *cp;
+ int r;
- buf_len = buffer_len(&iqueue);
+ buf_len = sshbuf_len(iqueue);
if (buf_len < 5)
return; /* Incomplete message. */
- cp = buffer_ptr(&iqueue);
+ cp = sshbuf_ptr(iqueue);
msg_len = get_u32(cp);
if (msg_len > MAX_MSG_LENGTH) {
error("bad message len %d", msg_len);
@@ -227,9 +276,10 @@ process(void)
}
if (buf_len < msg_len + 4)
return;
- buffer_consume(&iqueue, 4);
+ 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;
- type = buffer_get_char(&iqueue);
switch (type) {
case SSH_AGENTC_ADD_SMARTCARD_KEY:
debug("process_add");
@@ -248,17 +298,19 @@ process(void)
break;
}
/* discard the remaining bytes from the current packet */
- if (buf_len < buffer_len(&iqueue)) {
+ if (buf_len < sshbuf_len(iqueue)) {
error("iqueue grew unexpectedly");
cleanup_exit(255);
}
- consumed = buf_len - buffer_len(&iqueue);
+ 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)
- buffer_consume(&iqueue, msg_len - consumed);
+ if (msg_len > consumed) {
+ if ((r = sshbuf_consume(iqueue, msg_len - consumed)) != 0)
+ fatal("%s: buffer error: %s", __func__, ssh_err(r));
+ }
}
void
@@ -268,68 +320,78 @@ cleanup_exit(int i)
_exit(i);
}
+
int
main(int argc, char **argv)
{
- fd_set *rset, *wset;
- int in, out, max, log_stderr = 0;
- ssize_t len, olen, set_size;
+ 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);
- pkcs11_init(0);
- seed_rng();
- __progname = ssh_get_progname(argv[0]);
+ 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;
- max = 0;
- if (in > max)
- max = in;
- if (out > max)
- max = out;
+ if ((iqueue = sshbuf_new()) == NULL)
+ fatal("%s: sshbuf_new failed", __func__);
+ if ((oqueue = sshbuf_new()) == NULL)
+ fatal("%s: sshbuf_new failed", __func__);
- buffer_init(&iqueue);
- buffer_init(&oqueue);
-
- set_size = howmany(max + 1, NFDBITS) * sizeof(fd_mask);
- rset = (fd_set *)xmalloc(set_size);
- wset = (fd_set *)xmalloc(set_size);
-
- for (;;) {
- memset(rset, 0, set_size);
- memset(wset, 0, set_size);
+ 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 (buffer_check_alloc(&iqueue, sizeof(buf)) &&
- buffer_check_alloc(&oqueue, MAX_MSG_LENGTH))
- FD_SET(in, rset);
+ 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));
- olen = buffer_len(&oqueue);
- if (olen > 0)
- FD_SET(out, wset);
+ if (sshbuf_len(oqueue) > 0)
+ pfd[1].events = POLLOUT;
- if (select(max+1, rset, wset, NULL, NULL) < 0) {
- if (errno == EINTR)
+ if ((r = poll(pfd, 2, -1 /* INFTIM */)) <= 0) {
+ if (r == 0 || errno == EINTR)
continue;
- error("select: %s", strerror(errno));
- cleanup_exit(2);
+ fatal("poll: %s", strerror(errno));
}
/* copy stdin to iqueue */
- if (FD_ISSET(in, rset)) {
+ if ((pfd[0].revents & (POLLIN|POLLERR)) != 0) {
len = read(in, buf, sizeof buf);
if (len == 0) {
debug("read eof");
@@ -337,18 +399,21 @@ main(int argc, char **argv)
} else if (len < 0) {
error("read: %s", strerror(errno));
cleanup_exit(1);
- } else {
- buffer_append(&iqueue, buf, len);
+ } else if ((r = sshbuf_put(iqueue, buf, len)) != 0) {
+ fatal("%s: buffer error: %s",
+ __func__, ssh_err(r));
}
}
/* send oqueue to stdout */
- if (FD_ISSET(out, wset)) {
- len = write(out, buffer_ptr(&oqueue), olen);
+ 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 {
- buffer_consume(&oqueue, len);
+ } else if ((r = sshbuf_consume(oqueue, len)) != 0) {
+ fatal("%s: buffer error: %s",
+ __func__, ssh_err(r));
}
}
@@ -357,10 +422,27 @@ main(int argc, char **argv)
* into the output buffer, otherwise stop processing input
* and let the output queue drain.
*/
- if (buffer_check_alloc(&oqueue, MAX_MSG_LENGTH))
+ 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)