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-rw-r--r--kex.c869
1 files changed, 706 insertions, 163 deletions
diff --git a/kex.c b/kex.c
index 2a00d284..09c7258e 100644
--- a/kex.c
+++ b/kex.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kex.c,v 1.105 2015/01/30 00:22:25 djm Exp $ */
+/* $OpenBSD: kex.c,v 1.158 2020/03/13 04:01:56 djm Exp $ */
/*
* Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
*
@@ -25,20 +25,27 @@
#include "includes.h"
-#include <sys/param.h> /* MAX roundup */
-
+#include <sys/types.h>
+#include <errno.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include <unistd.h>
+#ifdef HAVE_POLL_H
+#include <poll.h>
+#endif
#ifdef WITH_OPENSSL
#include <openssl/crypto.h>
#include <openssl/dh.h>
#endif
+#include "ssh.h"
#include "ssh2.h"
+#include "atomicio.h"
+#include "version.h"
#include "packet.h"
#include "compat.h"
#include "cipher.h"
@@ -50,23 +57,27 @@
#include "misc.h"
#include "dispatch.h"
#include "monitor.h"
-#include "roaming.h"
#include "ssherr.h"
#include "sshbuf.h"
#include "digest.h"
-#if OPENSSL_VERSION_NUMBER >= 0x00907000L
-# if defined(HAVE_EVP_SHA256)
-# define evp_ssh_sha256 EVP_sha256
-# else
-extern const EVP_MD *evp_ssh_sha256(void);
-# endif
-#endif
-
/* prototype */
static int kex_choose_conf(struct ssh *);
-static int kex_input_newkeys(int, u_int32_t, void *);
+static int kex_input_newkeys(int, u_int32_t, struct ssh *);
+
+static const char *proposal_names[PROPOSAL_MAX] = {
+ "KEX algorithms",
+ "host key algorithms",
+ "ciphers ctos",
+ "ciphers stoc",
+ "MACs ctos",
+ "MACs stoc",
+ "compression ctos",
+ "compression stoc",
+ "languages ctos",
+ "languages stoc",
+};
struct kexalg {
char *name;
@@ -77,7 +88,10 @@ struct kexalg {
static const struct kexalg kexalgs[] = {
#ifdef WITH_OPENSSL
{ KEX_DH1, KEX_DH_GRP1_SHA1, 0, SSH_DIGEST_SHA1 },
- { KEX_DH14, KEX_DH_GRP14_SHA1, 0, SSH_DIGEST_SHA1 },
+ { KEX_DH14_SHA1, KEX_DH_GRP14_SHA1, 0, SSH_DIGEST_SHA1 },
+ { KEX_DH14_SHA256, KEX_DH_GRP14_SHA256, 0, SSH_DIGEST_SHA256 },
+ { KEX_DH16_SHA512, KEX_DH_GRP16_SHA512, 0, SSH_DIGEST_SHA512 },
+ { KEX_DH18_SHA512, KEX_DH_GRP18_SHA512, 0, SSH_DIGEST_SHA512 },
{ KEX_DHGEX_SHA1, KEX_DH_GEX_SHA1, 0, SSH_DIGEST_SHA1 },
#ifdef HAVE_EVP_SHA256
{ KEX_DHGEX_SHA256, KEX_DH_GEX_SHA256, 0, SSH_DIGEST_SHA256 },
@@ -95,8 +109,11 @@ static const struct kexalg kexalgs[] = {
#endif /* WITH_OPENSSL */
#if defined(HAVE_EVP_SHA256) || !defined(WITH_OPENSSL)
{ KEX_CURVE25519_SHA256, KEX_C25519_SHA256, 0, SSH_DIGEST_SHA256 },
+ { KEX_CURVE25519_SHA256_OLD, KEX_C25519_SHA256, 0, SSH_DIGEST_SHA256 },
+ { KEX_SNTRUP4591761X25519_SHA512, KEX_KEM_SNTRUP4591761X25519_SHA512, 0,
+ SSH_DIGEST_SHA512 },
#endif /* HAVE_EVP_SHA256 || !WITH_OPENSSL */
- { NULL, -1, -1, -1},
+ { NULL, 0, -1, -1},
};
char *
@@ -156,6 +173,148 @@ kex_names_valid(const char *names)
return 1;
}
+/*
+ * Concatenate algorithm names, avoiding duplicates in the process.
+ * Caller must free returned string.
+ */
+char *
+kex_names_cat(const char *a, const char *b)
+{
+ char *ret = NULL, *tmp = NULL, *cp, *p, *m;
+ size_t len;
+
+ if (a == NULL || *a == '\0')
+ return strdup(b);
+ if (b == NULL || *b == '\0')
+ return strdup(a);
+ if (strlen(b) > 1024*1024)
+ return NULL;
+ len = strlen(a) + strlen(b) + 2;
+ if ((tmp = cp = strdup(b)) == NULL ||
+ (ret = calloc(1, len)) == NULL) {
+ free(tmp);
+ return NULL;
+ }
+ strlcpy(ret, a, len);
+ for ((p = strsep(&cp, ",")); p && *p != '\0'; (p = strsep(&cp, ","))) {
+ if ((m = match_list(ret, p, NULL)) != NULL) {
+ free(m);
+ continue; /* Algorithm already present */
+ }
+ if (strlcat(ret, ",", len) >= len ||
+ strlcat(ret, p, len) >= len) {
+ free(tmp);
+ free(ret);
+ return NULL; /* Shouldn't happen */
+ }
+ }
+ free(tmp);
+ return ret;
+}
+
+/*
+ * Assemble a list of algorithms from a default list and a string from a
+ * configuration file. The user-provided string may begin with '+' to
+ * indicate that it should be appended to the default, '-' that the
+ * specified names should be removed, or '^' that they should be placed
+ * at the head.
+ */
+int
+kex_assemble_names(char **listp, const char *def, const char *all)
+{
+ char *cp, *tmp, *patterns;
+ char *list = NULL, *ret = NULL, *matching = NULL, *opatterns = NULL;
+ int r = SSH_ERR_INTERNAL_ERROR;
+
+ if (listp == NULL || def == NULL || all == NULL)
+ return SSH_ERR_INVALID_ARGUMENT;
+
+ if (*listp == NULL || **listp == '\0') {
+ if ((*listp = strdup(def)) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ return 0;
+ }
+
+ list = *listp;
+ *listp = NULL;
+ if (*list == '+') {
+ /* Append names to default list */
+ if ((tmp = kex_names_cat(def, list + 1)) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto fail;
+ }
+ free(list);
+ list = tmp;
+ } else if (*list == '-') {
+ /* Remove names from default list */
+ if ((*listp = match_filter_blacklist(def, list + 1)) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto fail;
+ }
+ free(list);
+ /* filtering has already been done */
+ return 0;
+ } else if (*list == '^') {
+ /* Place names at head of default list */
+ if ((tmp = kex_names_cat(list + 1, def)) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto fail;
+ }
+ free(list);
+ list = tmp;
+ } else {
+ /* Explicit list, overrides default - just use "list" as is */
+ }
+
+ /*
+ * The supplied names may be a pattern-list. For the -list case,
+ * the patterns are applied above. For the +list and explicit list
+ * cases we need to do it now.
+ */
+ ret = NULL;
+ if ((patterns = opatterns = strdup(list)) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto fail;
+ }
+ /* Apply positive (i.e. non-negated) patterns from the list */
+ while ((cp = strsep(&patterns, ",")) != NULL) {
+ if (*cp == '!') {
+ /* negated matches are not supported here */
+ r = SSH_ERR_INVALID_ARGUMENT;
+ goto fail;
+ }
+ free(matching);
+ if ((matching = match_filter_whitelist(all, cp)) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto fail;
+ }
+ if ((tmp = kex_names_cat(ret, matching)) == NULL) {
+ r = SSH_ERR_ALLOC_FAIL;
+ goto fail;
+ }
+ free(ret);
+ ret = tmp;
+ }
+ if (ret == NULL || *ret == '\0') {
+ /* An empty name-list is an error */
+ /* XXX better error code? */
+ r = SSH_ERR_INVALID_ARGUMENT;
+ goto fail;
+ }
+
+ /* success */
+ *listp = ret;
+ ret = NULL;
+ r = 0;
+
+ fail:
+ free(matching);
+ free(opatterns);
+ free(list);
+ free(ret);
+ return r;
+}
+
/* put algorithm proposal into buffer */
int
kex_prop2buf(struct sshbuf *b, char *proposal[PROPOSAL_MAX])
@@ -200,22 +359,29 @@ kex_buf2prop(struct sshbuf *raw, int *first_kex_follows, char ***propp)
r = SSH_ERR_ALLOC_FAIL;
goto out;
}
- if ((r = sshbuf_consume(b, KEX_COOKIE_LEN)) != 0) /* skip cookie */
+ if ((r = sshbuf_consume(b, KEX_COOKIE_LEN)) != 0) { /* skip cookie */
+ error("%s: consume cookie: %s", __func__, ssh_err(r));
goto out;
+ }
/* extract kex init proposal strings */
for (i = 0; i < PROPOSAL_MAX; i++) {
- if ((r = sshbuf_get_cstring(b, &(proposal[i]), NULL)) != 0)
+ if ((r = sshbuf_get_cstring(b, &(proposal[i]), NULL)) != 0) {
+ error("%s: parse proposal %u: %s", __func__,
+ i, ssh_err(r));
goto out;
- debug2("kex_parse_kexinit: %s", proposal[i]);
+ }
+ debug2("%s: %s", proposal_names[i], proposal[i]);
}
/* first kex follows / reserved */
- if ((r = sshbuf_get_u8(b, &v)) != 0 ||
- (r = sshbuf_get_u32(b, &i)) != 0)
+ if ((r = sshbuf_get_u8(b, &v)) != 0 || /* first_kex_follows */
+ (r = sshbuf_get_u32(b, &i)) != 0) { /* reserved */
+ error("%s: parse: %s", __func__, ssh_err(r));
goto out;
+ }
if (first_kex_follows != NULL)
- *first_kex_follows = i;
- debug2("kex_parse_kexinit: first_kex_follows %d ", v);
- debug2("kex_parse_kexinit: reserved %u ", i);
+ *first_kex_follows = v;
+ debug2("first_kex_follows %d ", v);
+ debug2("reserved %u ", i);
r = 0;
*propp = proposal;
out:
@@ -230,6 +396,8 @@ kex_prop_free(char **proposal)
{
u_int i;
+ if (proposal == NULL)
+ return;
for (i = 0; i < PROPOSAL_MAX; i++)
free(proposal[i]);
free(proposal);
@@ -237,9 +405,15 @@ kex_prop_free(char **proposal)
/* ARGSUSED */
static int
-kex_protocol_error(int type, u_int32_t seq, void *ctxt)
+kex_protocol_error(int type, u_int32_t seq, struct ssh *ssh)
{
- error("Hm, kex protocol error: type %d seq %u", type, seq);
+ int r;
+
+ error("kex protocol error: type %d seq %u", type, seq);
+ if ((r = sshpkt_start(ssh, SSH2_MSG_UNIMPLEMENTED)) != 0 ||
+ (r = sshpkt_put_u32(ssh, seq)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0)
+ return r;
return 0;
}
@@ -248,7 +422,31 @@ kex_reset_dispatch(struct ssh *ssh)
{
ssh_dispatch_range(ssh, SSH2_MSG_TRANSPORT_MIN,
SSH2_MSG_TRANSPORT_MAX, &kex_protocol_error);
- ssh_dispatch_set(ssh, SSH2_MSG_KEXINIT, &kex_input_kexinit);
+}
+
+static int
+kex_send_ext_info(struct ssh *ssh)
+{
+ int r;
+ char *algs;
+
+ debug("Sending SSH2_MSG_EXT_INFO");
+ if ((algs = sshkey_alg_list(0, 1, 1, ',')) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ /* XXX filter algs list by allowed pubkey/hostbased types */
+ if ((r = sshpkt_start(ssh, SSH2_MSG_EXT_INFO)) != 0 ||
+ (r = sshpkt_put_u32(ssh, 1)) != 0 ||
+ (r = sshpkt_put_cstring(ssh, "server-sig-algs")) != 0 ||
+ (r = sshpkt_put_cstring(ssh, algs)) != 0 ||
+ (r = sshpkt_send(ssh)) != 0) {
+ error("%s: compose: %s", __func__, ssh_err(r));
+ goto out;
+ }
+ /* success */
+ r = 0;
+ out:
+ free(algs);
+ return r;
}
int
@@ -261,23 +459,67 @@ kex_send_newkeys(struct ssh *ssh)
(r = sshpkt_send(ssh)) != 0)
return r;
debug("SSH2_MSG_NEWKEYS sent");
- debug("expecting SSH2_MSG_NEWKEYS");
ssh_dispatch_set(ssh, SSH2_MSG_NEWKEYS, &kex_input_newkeys);
+ if (ssh->kex->ext_info_c && (ssh->kex->flags & KEX_INITIAL) != 0)
+ if ((r = kex_send_ext_info(ssh)) != 0)
+ return r;
+ debug("expecting SSH2_MSG_NEWKEYS");
return 0;
}
+int
+kex_input_ext_info(int type, u_int32_t seq, struct ssh *ssh)
+{
+ struct kex *kex = ssh->kex;
+ u_int32_t i, ninfo;
+ char *name;
+ u_char *val;
+ size_t vlen;
+ int r;
+
+ debug("SSH2_MSG_EXT_INFO received");
+ ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &kex_protocol_error);
+ if ((r = sshpkt_get_u32(ssh, &ninfo)) != 0)
+ return r;
+ for (i = 0; i < ninfo; i++) {
+ if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0)
+ return r;
+ if ((r = sshpkt_get_string(ssh, &val, &vlen)) != 0) {
+ free(name);
+ return r;
+ }
+ if (strcmp(name, "server-sig-algs") == 0) {
+ /* Ensure no \0 lurking in value */
+ if (memchr(val, '\0', vlen) != NULL) {
+ error("%s: nul byte in %s", __func__, name);
+ return SSH_ERR_INVALID_FORMAT;
+ }
+ debug("%s: %s=<%s>", __func__, name, val);
+ kex->server_sig_algs = val;
+ val = NULL;
+ } else
+ debug("%s: %s (unrecognised)", __func__, name);
+ free(name);
+ free(val);
+ }
+ return sshpkt_get_end(ssh);
+}
+
static int
-kex_input_newkeys(int type, u_int32_t seq, void *ctxt)
+kex_input_newkeys(int type, u_int32_t seq, struct ssh *ssh)
{
- struct ssh *ssh = ctxt;
struct kex *kex = ssh->kex;
int r;
debug("SSH2_MSG_NEWKEYS received");
ssh_dispatch_set(ssh, SSH2_MSG_NEWKEYS, &kex_protocol_error);
+ ssh_dispatch_set(ssh, SSH2_MSG_KEXINIT, &kex_input_kexinit);
if ((r = sshpkt_get_end(ssh)) != 0)
return r;
+ if ((r = ssh_set_newkeys(ssh, MODE_IN)) != 0)
+ return r;
kex->done = 1;
+ kex->flags &= ~KEX_INITIAL;
sshbuf_reset(kex->peer);
/* sshbuf_reset(kex->my); */
kex->flags &= ~KEX_INIT_SENT;
@@ -293,23 +535,32 @@ kex_send_kexinit(struct ssh *ssh)
struct kex *kex = ssh->kex;
int r;
- if (kex == NULL)
+ if (kex == NULL) {
+ error("%s: no hex", __func__);
return SSH_ERR_INTERNAL_ERROR;
+ }
if (kex->flags & KEX_INIT_SENT)
return 0;
kex->done = 0;
/* generate a random cookie */
- if (sshbuf_len(kex->my) < KEX_COOKIE_LEN)
+ if (sshbuf_len(kex->my) < KEX_COOKIE_LEN) {
+ error("%s: bad kex length: %zu < %d", __func__,
+ sshbuf_len(kex->my), KEX_COOKIE_LEN);
return SSH_ERR_INVALID_FORMAT;
- if ((cookie = sshbuf_mutable_ptr(kex->my)) == NULL)
+ }
+ if ((cookie = sshbuf_mutable_ptr(kex->my)) == NULL) {
+ error("%s: buffer error", __func__);
return SSH_ERR_INTERNAL_ERROR;
+ }
arc4random_buf(cookie, KEX_COOKIE_LEN);
if ((r = sshpkt_start(ssh, SSH2_MSG_KEXINIT)) != 0 ||
(r = sshpkt_putb(ssh, kex->my)) != 0 ||
- (r = sshpkt_send(ssh)) != 0)
+ (r = sshpkt_send(ssh)) != 0) {
+ error("%s: compose reply: %s", __func__, ssh_err(r));
return r;
+ }
debug("SSH2_MSG_KEXINIT sent");
kex->flags |= KEX_INIT_SENT;
return 0;
@@ -317,9 +568,8 @@ kex_send_kexinit(struct ssh *ssh)
/* ARGSUSED */
int
-kex_input_kexinit(int type, u_int32_t seq, void *ctxt)
+kex_input_kexinit(int type, u_int32_t seq, struct ssh *ssh)
{
- struct ssh *ssh = ctxt;
struct kex *kex = ssh->kex;
const u_char *ptr;
u_int i;
@@ -327,20 +577,28 @@ kex_input_kexinit(int type, u_int32_t seq, void *ctxt)
int r;
debug("SSH2_MSG_KEXINIT received");
- if (kex == NULL)
- return SSH_ERR_INVALID_ARGUMENT;
-
+ if (kex == NULL) {
+ error("%s: no hex", __func__);
+ return SSH_ERR_INTERNAL_ERROR;
+ }
+ ssh_dispatch_set(ssh, SSH2_MSG_KEXINIT, NULL);
ptr = sshpkt_ptr(ssh, &dlen);
if ((r = sshbuf_put(kex->peer, ptr, dlen)) != 0)
return r;
/* discard packet */
- for (i = 0; i < KEX_COOKIE_LEN; i++)
- if ((r = sshpkt_get_u8(ssh, NULL)) != 0)
+ for (i = 0; i < KEX_COOKIE_LEN; i++) {
+ if ((r = sshpkt_get_u8(ssh, NULL)) != 0) {
+ error("%s: discard cookie: %s", __func__, ssh_err(r));
return r;
- for (i = 0; i < PROPOSAL_MAX; i++)
- if ((r = sshpkt_get_string(ssh, NULL, NULL)) != 0)
+ }
+ }
+ for (i = 0; i < PROPOSAL_MAX; i++) {
+ if ((r = sshpkt_get_string(ssh, NULL, NULL)) != 0) {
+ error("%s: discard proposal: %s", __func__, ssh_err(r));
return r;
+ }
+ }
/*
* XXX RFC4253 sec 7: "each side MAY guess" - currently no supported
* KEX method has the server move first, but a server might be using
@@ -365,33 +623,24 @@ kex_input_kexinit(int type, u_int32_t seq, void *ctxt)
if (kex->kex_type < KEX_MAX && kex->kex[kex->kex_type] != NULL)
return (kex->kex[kex->kex_type])(ssh);
+ error("%s: unknown kex type %u", __func__, kex->kex_type);
return SSH_ERR_INTERNAL_ERROR;
}
-int
-kex_new(struct ssh *ssh, char *proposal[PROPOSAL_MAX], struct kex **kexp)
+struct kex *
+kex_new(void)
{
struct kex *kex;
- int r;
- *kexp = NULL;
- if ((kex = calloc(1, sizeof(*kex))) == NULL)
- return SSH_ERR_ALLOC_FAIL;
- if ((kex->peer = sshbuf_new()) == NULL ||
- (kex->my = sshbuf_new()) == NULL) {
- r = SSH_ERR_ALLOC_FAIL;
- goto out;
- }
- if ((r = kex_prop2buf(kex->my, proposal)) != 0)
- goto out;
- kex->done = 0;
- kex_reset_dispatch(ssh);
- r = 0;
- *kexp = kex;
- out:
- if (r != 0)
+ if ((kex = calloc(1, sizeof(*kex))) == NULL ||
+ (kex->peer = sshbuf_new()) == NULL ||
+ (kex->my = sshbuf_new()) == NULL ||
+ (kex->client_version = sshbuf_new()) == NULL ||
+ (kex->server_version = sshbuf_new()) == NULL) {
kex_free(kex);
- return r;
+ return NULL;
+ }
+ return kex;
}
void
@@ -405,7 +654,7 @@ kex_free_newkeys(struct newkeys *newkeys)
newkeys->enc.key = NULL;
}
if (newkeys->enc.iv) {
- explicit_bzero(newkeys->enc.iv, newkeys->enc.block_size);
+ explicit_bzero(newkeys->enc.iv, newkeys->enc.iv_len);
free(newkeys->enc.iv);
newkeys->enc.iv = NULL;
}
@@ -421,8 +670,7 @@ kex_free_newkeys(struct newkeys *newkeys)
}
free(newkeys->mac.name);
explicit_bzero(&newkeys->mac, sizeof(newkeys->mac));
- explicit_bzero(newkeys, sizeof(*newkeys));
- free(newkeys);
+ freezero(newkeys, sizeof(*newkeys));
}
void
@@ -430,12 +678,13 @@ kex_free(struct kex *kex)
{
u_int mode;
+ if (kex == NULL)
+ return;
+
#ifdef WITH_OPENSSL
- if (kex->dh)
- DH_free(kex->dh);
+ DH_free(kex->dh);
#ifdef OPENSSL_HAS_ECC
- if (kex->ec_client_key)
- EC_KEY_free(kex->ec_client_key);
+ EC_KEY_free(kex->ec_client_key);
#endif /* OPENSSL_HAS_ECC */
#endif /* WITH_OPENSSL */
for (mode = 0; mode < MODE_MAX; mode++) {
@@ -444,18 +693,35 @@ kex_free(struct kex *kex)
}
sshbuf_free(kex->peer);
sshbuf_free(kex->my);
+ sshbuf_free(kex->client_version);
+ sshbuf_free(kex->server_version);
+ sshbuf_free(kex->client_pub);
free(kex->session_id);
- free(kex->client_version_string);
- free(kex->server_version_string);
+ free(kex->failed_choice);
+ free(kex->hostkey_alg);
+ free(kex->name);
free(kex);
}
int
+kex_ready(struct ssh *ssh, char *proposal[PROPOSAL_MAX])
+{
+ int r;
+
+ if ((r = kex_prop2buf(ssh->kex->my, proposal)) != 0)
+ return r;
+ ssh->kex->flags = KEX_INITIAL;
+ kex_reset_dispatch(ssh);
+ ssh_dispatch_set(ssh, SSH2_MSG_KEXINIT, &kex_input_kexinit);
+ return 0;
+}
+
+int
kex_setup(struct ssh *ssh, char *proposal[PROPOSAL_MAX])
{
int r;
- if ((r = kex_new(ssh, proposal, &ssh->kex)) != 0)
+ if ((r = kex_ready(ssh, proposal)) != 0)
return r;
if ((r = kex_send_kexinit(ssh)) != 0) { /* we start */
kex_free(ssh->kex);
@@ -465,6 +731,25 @@ kex_setup(struct ssh *ssh, char *proposal[PROPOSAL_MAX])
return 0;
}
+/*
+ * Request key re-exchange, returns 0 on success or a ssherr.h error
+ * code otherwise. Must not be called if KEX is incomplete or in-progress.
+ */
+int
+kex_start_rekex(struct ssh *ssh)
+{
+ if (ssh->kex == NULL) {
+ error("%s: no kex", __func__);
+ return SSH_ERR_INTERNAL_ERROR;
+ }
+ if (ssh->kex->done == 0) {
+ error("%s: requested twice", __func__);
+ return SSH_ERR_INTERNAL_ERROR;
+ }
+ ssh->kex->done = 0;
+ return kex_send_kexinit(ssh);
+}
+
static int
choose_enc(struct sshenc *enc, char *client, char *server)
{
@@ -472,8 +757,11 @@ choose_enc(struct sshenc *enc, char *client, char *server)
if (name == NULL)
return SSH_ERR_NO_CIPHER_ALG_MATCH;
- if ((enc->cipher = cipher_by_name(name)) == NULL)
+ if ((enc->cipher = cipher_by_name(name)) == NULL) {
+ error("%s: unsupported cipher %s", __func__, name);
+ free(name);
return SSH_ERR_INTERNAL_ERROR;
+ }
enc->name = name;
enc->enabled = 0;
enc->iv = NULL;
@@ -491,11 +779,11 @@ choose_mac(struct ssh *ssh, struct sshmac *mac, char *client, char *server)
if (name == NULL)
return SSH_ERR_NO_MAC_ALG_MATCH;
- if (mac_setup(mac, name) < 0)
+ if (mac_setup(mac, name) < 0) {
+ error("%s: unsupported MAC %s", __func__, name);
+ free(name);
return SSH_ERR_INTERNAL_ERROR;
- /* truncate the key */
- if (ssh->compat & SSH_BUG_HMAC)
- mac->key_len = 16;
+ }
mac->name = name;
mac->key = NULL;
mac->enabled = 0;
@@ -509,13 +797,18 @@ choose_comp(struct sshcomp *comp, char *client, char *server)
if (name == NULL)
return SSH_ERR_NO_COMPRESS_ALG_MATCH;
+#ifdef WITH_ZLIB
if (strcmp(name, "zlib@openssh.com") == 0) {
comp->type = COMP_DELAYED;
} else if (strcmp(name, "zlib") == 0) {
comp->type = COMP_ZLIB;
- } else if (strcmp(name, "none") == 0) {
+ } else
+#endif /* WITH_ZLIB */
+ if (strcmp(name, "none") == 0) {
comp->type = COMP_NONE;
} else {
+ error("%s: unsupported compression scheme %s", __func__, name);
+ free(name);
return SSH_ERR_INTERNAL_ERROR;
}
comp->name = name;
@@ -529,10 +822,13 @@ choose_kex(struct kex *k, char *client, char *server)
k->name = match_list(client, server, NULL);
+ debug("kex: algorithm: %s", k->name ? k->name : "(no match)");
if (k->name == NULL)
return SSH_ERR_NO_KEX_ALG_MATCH;
- if ((kexalg = kex_alg_by_name(k->name)) == NULL)
+ if ((kexalg = kex_alg_by_name(k->name)) == NULL) {
+ error("%s: unsupported KEX method %s", __func__, k->name);
return SSH_ERR_INTERNAL_ERROR;
+ }
k->kex_type = kexalg->type;
k->hash_alg = kexalg->hash_alg;
k->ec_nid = kexalg->ec_nid;
@@ -542,15 +838,19 @@ choose_kex(struct kex *k, char *client, char *server)
static int
choose_hostkeyalg(struct kex *k, char *client, char *server)
{
- char *hostkeyalg = match_list(client, server, NULL);
+ k->hostkey_alg = match_list(client, server, NULL);
- if (hostkeyalg == NULL)
+ debug("kex: host key algorithm: %s",
+ k->hostkey_alg ? k->hostkey_alg : "(no match)");
+ if (k->hostkey_alg == NULL)
return SSH_ERR_NO_HOSTKEY_ALG_MATCH;
- k->hostkey_type = sshkey_type_from_name(hostkeyalg);
- if (k->hostkey_type == KEY_UNSPEC)
+ k->hostkey_type = sshkey_type_from_name(k->hostkey_alg);
+ if (k->hostkey_type == KEY_UNSPEC) {
+ error("%s: unsupported hostkey algorithm %s", __func__,
+ k->hostkey_alg);
return SSH_ERR_INTERNAL_ERROR;
- k->hostkey_nid = sshkey_ecdsa_nid_from_name(hostkeyalg);
- free(hostkeyalg);
+ }
+ k->hostkey_nid = sshkey_ecdsa_nid_from_name(k->hostkey_alg);
return 0;
}
@@ -589,8 +889,11 @@ kex_choose_conf(struct ssh *ssh)
u_int mode, ctos, need, dh_need, authlen;
int r, first_kex_follows;
- if ((r = kex_buf2prop(kex->my, NULL, &my)) != 0 ||
- (r = kex_buf2prop(kex->peer, &first_kex_follows, &peer)) != 0)
+ debug2("local %s KEXINIT proposal", kex->server ? "server" : "client");
+ if ((r = kex_buf2prop(kex->my, NULL, &my)) != 0)
+ goto out;
+ debug2("peer %s KEXINIT proposal", kex->server ? "client" : "server");
+ if ((r = kex_buf2prop(kex->peer, &first_kex_follows, &peer)) != 0)
goto out;
if (kex->server) {
@@ -601,18 +904,28 @@ kex_choose_conf(struct ssh *ssh)
sprop=peer;
}
- /* Check whether server offers roaming */
- if (!kex->server) {
- char *roaming = match_list(KEX_RESUME,
- peer[PROPOSAL_KEX_ALGS], NULL);
+ /* Check whether client supports ext_info_c */
+ if (kex->server && (kex->flags & KEX_INITIAL)) {
+ char *ext;
- if (roaming) {
- kex->roaming = 1;
- free(roaming);
- }
+ ext = match_list("ext-info-c", peer[PROPOSAL_KEX_ALGS], NULL);
+ kex->ext_info_c = (ext != NULL);
+ free(ext);
}
/* Algorithm Negotiation */
+ if ((r = choose_kex(kex, cprop[PROPOSAL_KEX_ALGS],
+ sprop[PROPOSAL_KEX_ALGS])) != 0) {
+ kex->failed_choice = peer[PROPOSAL_KEX_ALGS];
+ peer[PROPOSAL_KEX_ALGS] = NULL;
+ goto out;
+ }
+ if ((r = choose_hostkeyalg(kex, cprop[PROPOSAL_SERVER_HOST_KEY_ALGS],
+ sprop[PROPOSAL_SERVER_HOST_KEY_ALGS])) != 0) {
+ kex->failed_choice = peer[PROPOSAL_SERVER_HOST_KEY_ALGS];
+ peer[PROPOSAL_SERVER_HOST_KEY_ALGS] = NULL;
+ goto out;
+ }
for (mode = 0; mode < MODE_MAX; mode++) {
if ((newkeys = calloc(1, sizeof(*newkeys))) == NULL) {
r = SSH_ERR_ALLOC_FAIL;
@@ -625,47 +938,50 @@ kex_choose_conf(struct ssh *ssh)
nmac = ctos ? PROPOSAL_MAC_ALGS_CTOS : PROPOSAL_MAC_ALGS_STOC;
ncomp = ctos ? PROPOSAL_COMP_ALGS_CTOS : PROPOSAL_COMP_ALGS_STOC;
if ((r = choose_enc(&newkeys->enc, cprop[nenc],
- sprop[nenc])) != 0)
+ sprop[nenc])) != 0) {
+ kex->failed_choice = peer[nenc];
+ peer[nenc] = NULL;
goto out;
+ }
authlen = cipher_authlen(newkeys->enc.cipher);
/* ignore mac for authenticated encryption */
if (authlen == 0 &&
(r = choose_mac(ssh, &newkeys->mac, cprop[nmac],
- sprop[nmac])) != 0)
+ sprop[nmac])) != 0) {
+ kex->failed_choice = peer[nmac];
+ peer[nmac] = NULL;
goto out;
+ }
if ((r = choose_comp(&newkeys->comp, cprop[ncomp],
- sprop[ncomp])) != 0)
+ sprop[ncomp])) != 0) {
+ kex->failed_choice = peer[ncomp];
+ peer[ncomp] = NULL;
goto out;
- debug("kex: %s %s %s %s",
+ }
+ debug("kex: %s cipher: %s MAC: %s compression: %s",
ctos ? "client->server" : "server->client",
newkeys->enc.name,
authlen == 0 ? newkeys->mac.name : "<implicit>",
newkeys->comp.name);
}
- if ((r = choose_kex(kex, cprop[PROPOSAL_KEX_ALGS],
- sprop[PROPOSAL_KEX_ALGS])) != 0 ||
- (r = choose_hostkeyalg(kex, cprop[PROPOSAL_SERVER_HOST_KEY_ALGS],
- sprop[PROPOSAL_SERVER_HOST_KEY_ALGS])) != 0)
- goto out;
need = dh_need = 0;
for (mode = 0; mode < MODE_MAX; mode++) {
newkeys = kex->newkeys[mode];
- need = MAX(need, newkeys->enc.key_len);
- need = MAX(need, newkeys->enc.block_size);
- need = MAX(need, newkeys->enc.iv_len);
- need = MAX(need, newkeys->mac.key_len);
- dh_need = MAX(dh_need, cipher_seclen(newkeys->enc.cipher));
- dh_need = MAX(dh_need, newkeys->enc.block_size);
- dh_need = MAX(dh_need, newkeys->enc.iv_len);
- dh_need = MAX(dh_need, newkeys->mac.key_len);
+ need = MAXIMUM(need, newkeys->enc.key_len);
+ need = MAXIMUM(need, newkeys->enc.block_size);
+ need = MAXIMUM(need, newkeys->enc.iv_len);
+ need = MAXIMUM(need, newkeys->mac.key_len);
+ dh_need = MAXIMUM(dh_need, cipher_seclen(newkeys->enc.cipher));
+ dh_need = MAXIMUM(dh_need, newkeys->enc.block_size);
+ dh_need = MAXIMUM(dh_need, newkeys->enc.iv_len);
+ dh_need = MAXIMUM(dh_need, newkeys->mac.key_len);
}
/* XXX need runden? */
kex->we_need = need;
kex->dh_need = dh_need;
/* ignore the next message if the proposals do not match */
- if (first_kex_follows && !proposals_match(my, peer) &&
- !(ssh->compat & SSH_BUG_FIRSTKEX))
+ if (first_kex_follows && !proposals_match(my, peer))
ssh->dispatch_skip_packets = 1;
r = 0;
out:
@@ -688,7 +1004,7 @@ derive_key(struct ssh *ssh, int id, u_int need, u_char *hash, u_int hashlen,
if ((mdsz = ssh_digest_bytes(kex->hash_alg)) == 0)
return SSH_ERR_INVALID_ARGUMENT;
- if ((digest = calloc(1, roundup(need, mdsz))) == NULL) {
+ if ((digest = calloc(1, ROUNDUP(need, mdsz))) == NULL) {
r = SSH_ERR_ALLOC_FAIL;
goto out;
}
@@ -702,6 +1018,7 @@ derive_key(struct ssh *ssh, int id, u_int need, u_char *hash, u_int hashlen,
kex->session_id_len) != 0 ||
ssh_digest_final(hashctx, digest, mdsz) != 0) {
r = SSH_ERR_LIBCRYPTO_ERROR;
+ error("%s: KEX hash failed", __func__);
goto out;
}
ssh_digest_free(hashctx);
@@ -718,6 +1035,7 @@ derive_key(struct ssh *ssh, int id, u_int need, u_char *hash, u_int hashlen,
ssh_digest_update(hashctx, hash, hashlen) != 0 ||
ssh_digest_update(hashctx, digest, have) != 0 ||
ssh_digest_final(hashctx, digest + have, mdsz) != 0) {
+ error("%s: KDF failed", __func__);
r = SSH_ERR_LIBCRYPTO_ERROR;
goto out;
}
@@ -732,8 +1050,7 @@ derive_key(struct ssh *ssh, int id, u_int need, u_char *hash, u_int hashlen,
digest = NULL;
r = 0;
out:
- if (digest)
- free(digest);
+ free(digest);
ssh_digest_free(hashctx);
return r;
}
@@ -748,6 +1065,14 @@ kex_derive_keys(struct ssh *ssh, u_char *hash, u_int hashlen,
u_int i, j, mode, ctos;
int r;
+ /* save initial hash as session id */
+ if (kex->session_id == NULL) {
+ kex->session_id_len = hashlen;
+ kex->session_id = malloc(kex->session_id_len);
+ if (kex->session_id == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ memcpy(kex->session_id, hash, kex->session_id_len);
+ }
for (i = 0; i < NKEYS; i++) {
if ((r = derive_key(ssh, 'A'+i, kex->we_need, hash, hashlen,
shared_secret, &keys[i])) != 0) {
@@ -766,70 +1091,288 @@ kex_derive_keys(struct ssh *ssh, u_char *hash, u_int hashlen,
return 0;
}
-#ifdef WITH_OPENSSL
int
-kex_derive_keys_bn(struct ssh *ssh, u_char *hash, u_int hashlen,
- const BIGNUM *secret)
+kex_load_hostkey(struct ssh *ssh, struct sshkey **prvp, struct sshkey **pubp)
{
- struct sshbuf *shared_secret;
- int r;
+ struct kex *kex = ssh->kex;
- if ((shared_secret = sshbuf_new()) == NULL)
- return SSH_ERR_ALLOC_FAIL;
- if ((r = sshbuf_put_bignum2(shared_secret, secret)) == 0)
- r = kex_derive_keys(ssh, hash, hashlen, shared_secret);
- sshbuf_free(shared_secret);
- return r;
+ *pubp = NULL;
+ *prvp = NULL;
+ if (kex->load_host_public_key == NULL ||
+ kex->load_host_private_key == NULL) {
+ error("%s: missing hostkey loader", __func__);
+ return SSH_ERR_INVALID_ARGUMENT;
+ }
+ *pubp = kex->load_host_public_key(kex->hostkey_type,
+ kex->hostkey_nid, ssh);
+ *prvp = kex->load_host_private_key(kex->hostkey_type,
+ kex->hostkey_nid, ssh);
+ if (*pubp == NULL)
+ return SSH_ERR_NO_HOSTKEY_LOADED;
+ return 0;
+}
+
+int
+kex_verify_host_key(struct ssh *ssh, struct sshkey *server_host_key)
+{
+ struct kex *kex = ssh->kex;
+
+ if (kex->verify_host_key == NULL) {
+ error("%s: missing hostkey verifier", __func__);
+ return SSH_ERR_INVALID_ARGUMENT;
+ }
+ if (server_host_key->type != kex->hostkey_type ||
+ (kex->hostkey_type == KEY_ECDSA &&
+ server_host_key->ecdsa_nid != kex->hostkey_nid))
+ return SSH_ERR_KEY_TYPE_MISMATCH;
+ if (kex->verify_host_key(server_host_key, ssh) == -1)
+ return SSH_ERR_SIGNATURE_INVALID;
+ return 0;
+}
+
+#if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
+void
+dump_digest(const char *msg, const u_char *digest, int len)
+{
+ fprintf(stderr, "%s\n", msg);
+ sshbuf_dump_data(digest, len, stderr);
}
#endif
-#ifdef WITH_SSH1
+/*
+ * Send a plaintext error message to the peer, suffixed by \r\n.
+ * Only used during banner exchange, and there only for the server.
+ */
+static void
+send_error(struct ssh *ssh, char *msg)
+{
+ char *crnl = "\r\n";
+
+ if (!ssh->kex->server)
+ return;
+
+ if (atomicio(vwrite, ssh_packet_get_connection_out(ssh),
+ msg, strlen(msg)) != strlen(msg) ||
+ atomicio(vwrite, ssh_packet_get_connection_out(ssh),
+ crnl, strlen(crnl)) != strlen(crnl))
+ error("%s: write: %.100s", __func__, strerror(errno));
+}
+
+/*
+ * Sends our identification string and waits for the peer's. Will block for
+ * up to timeout_ms (or indefinitely if timeout_ms <= 0).
+ * Returns on 0 success or a ssherr.h code on failure.
+ */
int
-derive_ssh1_session_id(BIGNUM *host_modulus, BIGNUM *server_modulus,
- u_int8_t cookie[8], u_int8_t id[16])
+kex_exchange_identification(struct ssh *ssh, int timeout_ms,
+ const char *version_addendum)
{
- u_int8_t hbuf[2048], sbuf[2048], obuf[SSH_DIGEST_MAX_LENGTH];
- struct ssh_digest_ctx *hashctx = NULL;
- size_t hlen, slen;
- int r;
+ int remote_major, remote_minor, mismatch, oerrno = 0;
+ size_t len, i, n;
+ int r, expect_nl;
+ u_char c;
+ struct sshbuf *our_version = ssh->kex->server ?
+ ssh->kex->server_version : ssh->kex->client_version;
+ struct sshbuf *peer_version = ssh->kex->server ?
+ ssh->kex->client_version : ssh->kex->server_version;
+ char *our_version_string = NULL, *peer_version_string = NULL;
+ char *cp, *remote_version = NULL;
+
+ /* Prepare and send our banner */
+ sshbuf_reset(our_version);
+ if (version_addendum != NULL && *version_addendum == '\0')
+ version_addendum = NULL;
+ if ((r = sshbuf_putf(our_version, "SSH-%d.%d-%.100s%s%s\r\n",
+ PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2, SSH_VERSION,
+ version_addendum == NULL ? "" : " ",
+ version_addendum == NULL ? "" : version_addendum)) != 0) {
+ oerrno = errno;
+ error("%s: sshbuf_putf: %s", __func__, ssh_err(r));
+ goto out;
+ }
- hlen = BN_num_bytes(host_modulus);
- slen = BN_num_bytes(server_modulus);
- if (hlen < (512 / 8) || (u_int)hlen > sizeof(hbuf) ||
- slen < (512 / 8) || (u_int)slen > sizeof(sbuf))
- return SSH_ERR_KEY_BITS_MISMATCH;
- if (BN_bn2bin(host_modulus, hbuf) <= 0 ||
- BN_bn2bin(server_modulus, sbuf) <= 0) {
- r = SSH_ERR_LIBCRYPTO_ERROR;
+ if (atomicio(vwrite, ssh_packet_get_connection_out(ssh),
+ sshbuf_mutable_ptr(our_version),
+ sshbuf_len(our_version)) != sshbuf_len(our_version)) {
+ oerrno = errno;
+ debug("%s: write: %.100s", __func__, strerror(errno));
+ r = SSH_ERR_SYSTEM_ERROR;
+ goto out;
+ }
+ if ((r = sshbuf_consume_end(our_version, 2)) != 0) { /* trim \r\n */
+ oerrno = errno;
+ error("%s: sshbuf_consume_end: %s", __func__, ssh_err(r));
goto out;
}
- if ((hashctx = ssh_digest_start(SSH_DIGEST_MD5)) == NULL) {
+ our_version_string = sshbuf_dup_string(our_version);
+ if (our_version_string == NULL) {
+ error("%s: sshbuf_dup_string failed", __func__);
r = SSH_ERR_ALLOC_FAIL;
goto out;
}
- if (ssh_digest_update(hashctx, hbuf, hlen) != 0 ||
- ssh_digest_update(hashctx, sbuf, slen) != 0 ||
- ssh_digest_update(hashctx, cookie, 8) != 0 ||
- ssh_digest_final(hashctx, obuf, sizeof(obuf)) != 0) {
- r = SSH_ERR_LIBCRYPTO_ERROR;
+ debug("Local version string %.100s", our_version_string);
+
+ /* Read other side's version identification. */
+ for (n = 0; ; n++) {
+ if (n >= SSH_MAX_PRE_BANNER_LINES) {
+ send_error(ssh, "No SSH identification string "
+ "received.");
+ error("%s: No SSH version received in first %u lines "
+ "from server", __func__, SSH_MAX_PRE_BANNER_LINES);
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ sshbuf_reset(peer_version);
+ expect_nl = 0;
+ for (i = 0; ; i++) {
+ if (timeout_ms > 0) {
+ r = waitrfd(ssh_packet_get_connection_in(ssh),
+ &timeout_ms);
+ if (r == -1 && errno == ETIMEDOUT) {
+ send_error(ssh, "Timed out waiting "
+ "for SSH identification string.");
+ error("Connection timed out during "
+ "banner exchange");
+ r = SSH_ERR_CONN_TIMEOUT;
+ goto out;
+ } else if (r == -1) {
+ oerrno = errno;
+ error("%s: %s",
+ __func__, strerror(errno));
+ r = SSH_ERR_SYSTEM_ERROR;
+ goto out;
+ }
+ }
+
+ len = atomicio(read, ssh_packet_get_connection_in(ssh),
+ &c, 1);
+ if (len != 1 && errno == EPIPE) {
+ error("%s: Connection closed by remote host",
+ __func__);
+ r = SSH_ERR_CONN_CLOSED;
+ goto out;
+ } else if (len != 1) {
+ oerrno = errno;
+ error("%s: read: %.100s",
+ __func__, strerror(errno));
+ r = SSH_ERR_SYSTEM_ERROR;
+ goto out;
+ }
+ if (c == '\r') {
+ expect_nl = 1;
+ continue;
+ }
+ if (c == '\n')
+ break;
+ if (c == '\0' || expect_nl) {
+ error("%s: banner line contains invalid "
+ "characters", __func__);
+ goto invalid;
+ }
+ if ((r = sshbuf_put_u8(peer_version, c)) != 0) {
+ oerrno = errno;
+ error("%s: sshbuf_put: %s",
+ __func__, ssh_err(r));
+ goto out;
+ }
+ if (sshbuf_len(peer_version) > SSH_MAX_BANNER_LEN) {
+ error("%s: banner line too long", __func__);
+ goto invalid;
+ }
+ }
+ /* Is this an actual protocol banner? */
+ if (sshbuf_len(peer_version) > 4 &&
+ memcmp(sshbuf_ptr(peer_version), "SSH-", 4) == 0)
+ break;
+ /* If not, then just log the line and continue */
+ if ((cp = sshbuf_dup_string(peer_version)) == NULL) {
+ error("%s: sshbuf_dup_string failed", __func__);
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+ /* Do not accept lines before the SSH ident from a client */
+ if (ssh->kex->server) {
+ error("%s: client sent invalid protocol identifier "
+ "\"%.256s\"", __func__, cp);
+ free(cp);
+ goto invalid;
+ }
+ debug("%s: banner line %zu: %s", __func__, n, cp);
+ free(cp);
+ }
+ peer_version_string = sshbuf_dup_string(peer_version);
+ if (peer_version_string == NULL)
+ error("%s: sshbuf_dup_string failed", __func__);
+ /* XXX must be same size for sscanf */
+ if ((remote_version = calloc(1, sshbuf_len(peer_version))) == NULL) {
+ error("%s: calloc failed", __func__);
+ r = SSH_ERR_ALLOC_FAIL;
+ goto out;
+ }
+
+ /*
+ * Check that the versions match. In future this might accept
+ * several versions and set appropriate flags to handle them.
+ */
+ if (sscanf(peer_version_string, "SSH-%d.%d-%[^\n]\n",
+ &remote_major, &remote_minor, remote_version) != 3) {
+ error("Bad remote protocol version identification: '%.100s'",
+ peer_version_string);
+ invalid:
+ send_error(ssh, "Invalid SSH identification string.");
+ r = SSH_ERR_INVALID_FORMAT;
+ goto out;
+ }
+ debug("Remote protocol version %d.%d, remote software version %.100s",
+ remote_major, remote_minor, remote_version);
+ ssh->compat = compat_datafellows(remote_version);
+
+ mismatch = 0;
+ switch (remote_major) {
+ case 2:
+ break;
+ case 1:
+ if (remote_minor != 99)
+ mismatch = 1;
+ break;
+ default:
+ mismatch = 1;
+ break;
+ }
+ if (mismatch) {
+ error("Protocol major versions differ: %d vs. %d",
+ PROTOCOL_MAJOR_2, remote_major);
+ send_error(ssh, "Protocol major versions differ.");
+ r = SSH_ERR_NO_PROTOCOL_VERSION;
goto out;
}
- memcpy(id, obuf, ssh_digest_bytes(SSH_DIGEST_MD5));
+
+ if (ssh->kex->server && (ssh->compat & SSH_BUG_PROBE) != 0) {
+ logit("probed from %s port %d with %s. Don't panic.",
+ ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
+ peer_version_string);
+ r = SSH_ERR_CONN_CLOSED; /* XXX */
+ goto out;
+ }
+ if (ssh->kex->server && (ssh->compat & SSH_BUG_SCANNER) != 0) {
+ logit("scanned from %s port %d with %s. Don't panic.",
+ ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
+ peer_version_string);
+ r = SSH_ERR_CONN_CLOSED; /* XXX */
+ goto out;
+ }
+ if ((ssh->compat & SSH_BUG_RSASIGMD5) != 0) {
+ logit("Remote version \"%.100s\" uses unsafe RSA signature "
+ "scheme; disabling use of RSA keys", remote_version);
+ }
+ /* success */
r = 0;
out:
- ssh_digest_free(hashctx);
- explicit_bzero(hbuf, sizeof(hbuf));
- explicit_bzero(sbuf, sizeof(sbuf));
- explicit_bzero(obuf, sizeof(obuf));
+ free(our_version_string);
+ free(peer_version_string);
+ free(remote_version);
+ if (r == SSH_ERR_SYSTEM_ERROR)
+ errno = oerrno;
return r;
}
-#endif
-#if defined(DEBUG_KEX) || defined(DEBUG_KEXDH) || defined(DEBUG_KEXECDH)
-void
-dump_digest(char *msg, u_char *digest, int len)
-{
- fprintf(stderr, "%s\n", msg);
- sshbuf_dump_data(digest, len, stderr);
-}
-#endif
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-03 04:23:54 +0000