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-rw-r--r--ssh_api.c174
1 files changed, 96 insertions, 78 deletions
diff --git a/ssh_api.c b/ssh_api.c
index c84b4e713bf40..57509973b5103 100644
--- a/ssh_api.c
+++ b/ssh_api.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh_api.c,v 1.8 2017/04/30 23:13:25 djm Exp $ */
+/* $OpenBSD: ssh_api.c,v 1.15 2019/01/21 10:38:54 djm Exp $ */
/*
* Copyright (c) 2012 Markus Friedl. All rights reserved.
*
@@ -29,17 +29,19 @@
#include "ssherr.h"
#include "sshbuf.h"
+#include "openbsd-compat/openssl-compat.h"
+
#include <string.h>
int _ssh_exchange_banner(struct ssh *);
-int _ssh_send_banner(struct ssh *, char **);
-int _ssh_read_banner(struct ssh *, char **);
+int _ssh_send_banner(struct ssh *, struct sshbuf *);
+int _ssh_read_banner(struct ssh *, struct sshbuf *);
int _ssh_order_hostkeyalgs(struct ssh *);
int _ssh_verify_host_key(struct sshkey *, struct ssh *);
struct sshkey *_ssh_host_public_key(int, int, struct ssh *);
struct sshkey *_ssh_host_private_key(int, int, struct ssh *);
-int _ssh_host_key_sign(struct sshkey *, struct sshkey *,
- u_char **, size_t *, const u_char *, size_t, const char *, u_int);
+int _ssh_host_key_sign(struct ssh *, struct sshkey *, struct sshkey *,
+ u_char **, size_t *, const u_char *, size_t, const char *);
/*
* stubs for the server side implementation of kex.
@@ -79,9 +81,7 @@ ssh_init(struct ssh **sshp, int is_server, struct kex_params *kex_params)
int r;
if (!called) {
-#ifdef WITH_OPENSSL
- OpenSSL_add_all_algorithms();
-#endif /* WITH_OPENSSL */
+ seed_rng();
called = 1;
}
@@ -92,42 +92,44 @@ ssh_init(struct ssh **sshp, int is_server, struct kex_params *kex_params)
/* Initialize key exchange */
proposal = kex_params ? kex_params->proposal : myproposal;
- if ((r = kex_new(ssh, proposal, &ssh->kex)) != 0) {
+ if ((r = kex_ready(ssh, proposal)) != 0) {
ssh_free(ssh);
return r;
}
ssh->kex->server = is_server;
if (is_server) {
#ifdef WITH_OPENSSL
- ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
- ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
- ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_server;
- ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_server;
- ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_server;
+ ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_server;
+ ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_server;
+ ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_server;
+ ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_server;
+ ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_server;
ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
# ifdef OPENSSL_HAS_ECC
- ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
+ ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_server;
# endif
#endif /* WITH_OPENSSL */
- ssh->kex->kex[KEX_C25519_SHA256] = kexc25519_server;
+ ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_server;
+ ssh->kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_gen_server;
ssh->kex->load_host_public_key=&_ssh_host_public_key;
ssh->kex->load_host_private_key=&_ssh_host_private_key;
ssh->kex->sign=&_ssh_host_key_sign;
} else {
#ifdef WITH_OPENSSL
- ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
- ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
- ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_client;
- ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_client;
- ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_client;
+ ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_client;
+ ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_client;
+ ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_client;
+ ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_client;
+ ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_client;
ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
# ifdef OPENSSL_HAS_ECC
- ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
+ ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_client;
# endif
#endif /* WITH_OPENSSL */
- ssh->kex->kex[KEX_C25519_SHA256] = kexc25519_client;
+ ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
+ ssh->kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_gen_client;
ssh->kex->verify_host_key =&_ssh_verify_host_key;
}
*sshp = ssh;
@@ -236,8 +238,8 @@ ssh_packet_next(struct ssh *ssh, u_char *typep)
* enough data.
*/
*typep = SSH_MSG_NONE;
- if (ssh->kex->client_version_string == NULL ||
- ssh->kex->server_version_string == NULL)
+ if (sshbuf_len(ssh->kex->client_version) == 0 ||
+ sshbuf_len(ssh->kex->server_version) == 0)
return _ssh_exchange_banner(ssh);
/*
* If we enough data and a dispatch function then
@@ -312,39 +314,46 @@ ssh_input_space(struct ssh *ssh, size_t len)
/* Read other side's version identification. */
int
-_ssh_read_banner(struct ssh *ssh, char **bannerp)
+_ssh_read_banner(struct ssh *ssh, struct sshbuf *banner)
{
- struct sshbuf *input;
- const char *s;
- char buf[256], remote_version[256]; /* must be same size! */
+ struct sshbuf *input = ssh_packet_get_input(ssh);
const char *mismatch = "Protocol mismatch.\r\n";
- int r, remote_major, remote_minor;
- size_t i, n, j, len;
+ const u_char *s = sshbuf_ptr(input);
+ u_char c;
+ char *cp, *remote_version;
+ int r, remote_major, remote_minor, expect_nl;
+ size_t n, j;
- *bannerp = NULL;
- input = ssh_packet_get_input(ssh);
- len = sshbuf_len(input);
- s = (const char *)sshbuf_ptr(input);
for (j = n = 0;;) {
- for (i = 0; i < sizeof(buf) - 1; i++) {
- if (j >= len)
- return (0);
- buf[i] = s[j++];
- if (buf[i] == '\r') {
- buf[i] = '\n';
- buf[i + 1] = 0;
- continue; /**XXX wait for \n */
+ sshbuf_reset(banner);
+ expect_nl = 0;
+ for (;;) {
+ if (j >= sshbuf_len(input))
+ return 0; /* insufficient data in input buf */
+ c = s[j++];
+ if (c == '\r') {
+ expect_nl = 1;
+ continue;
}
- if (buf[i] == '\n') {
- buf[i + 1] = 0;
+ if (c == '\n')
break;
- }
+ if (expect_nl)
+ goto bad;
+ if ((r = sshbuf_put_u8(banner, c)) != 0)
+ return r;
+ if (sshbuf_len(banner) > SSH_MAX_BANNER_LEN)
+ goto bad;
}
- buf[sizeof(buf) - 1] = 0;
- if (strncmp(buf, "SSH-", 4) == 0)
+ if (sshbuf_len(banner) >= 4 &&
+ memcmp(sshbuf_ptr(banner), "SSH-", 4) == 0)
break;
- debug("ssh_exchange_identification: %s", buf);
- if (ssh->kex->server || ++n > 65536) {
+ if ((cp = sshbuf_dup_string(banner)) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ debug("%s: %s", __func__, cp);
+ free(cp);
+ /* Accept lines before banner only on client */
+ if (ssh->kex->server || ++n > SSH_MAX_PRE_BANNER_LINES) {
+ bad:
if ((r = sshbuf_put(ssh_packet_get_output(ssh),
mismatch, strlen(mismatch))) != 0)
return r;
@@ -354,11 +363,17 @@ _ssh_read_banner(struct ssh *ssh, char **bannerp)
if ((r = sshbuf_consume(input, j)) != 0)
return r;
+ if ((cp = sshbuf_dup_string(banner)) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+ /* XXX remote version must be the same size as banner for sscanf */
+ if ((remote_version = calloc(1, sshbuf_len(banner))) == NULL)
+ return SSH_ERR_ALLOC_FAIL;
+
/*
* Check that the versions match. In future this might accept
* several versions and set appropriate flags to handle them.
*/
- if (sscanf(buf, "SSH-%d.%d-%[^\n]\n",
+ if (sscanf(cp, "SSH-%d.%d-%[^\n]\n",
&remote_major, &remote_minor, remote_version) != 3)
return SSH_ERR_INVALID_FORMAT;
debug("Remote protocol version %d.%d, remote software version %.100s",
@@ -371,27 +386,29 @@ _ssh_read_banner(struct ssh *ssh, char **bannerp)
}
if (remote_major != 2)
return SSH_ERR_PROTOCOL_MISMATCH;
- chop(buf);
- debug("Remote version string %.100s", buf);
- if ((*bannerp = strdup(buf)) == NULL)
- return SSH_ERR_ALLOC_FAIL;
+ debug("Remote version string %.100s", cp);
+ free(cp);
return 0;
}
/* Send our own protocol version identification. */
int
-_ssh_send_banner(struct ssh *ssh, char **bannerp)
+_ssh_send_banner(struct ssh *ssh, struct sshbuf *banner)
{
- char buf[256];
+ char *cp;
int r;
- snprintf(buf, sizeof buf, "SSH-2.0-%.100s\r\n", SSH_VERSION);
- if ((r = sshbuf_put(ssh_packet_get_output(ssh), buf, strlen(buf))) != 0)
+ if ((r = sshbuf_putf(banner, "SSH-2.0-%.100s\r\n", SSH_VERSION)) != 0)
+ return r;
+ if ((r = sshbuf_putb(ssh_packet_get_output(ssh), banner)) != 0)
+ return r;
+ /* Remove trailing \r\n */
+ if ((r = sshbuf_consume_end(banner, 2)) != 0)
return r;
- chop(buf);
- debug("Local version string %.100s", buf);
- if ((*bannerp = strdup(buf)) == NULL)
+ if ((cp = sshbuf_dup_string(banner)) == NULL)
return SSH_ERR_ALLOC_FAIL;
+ debug("Local version string %.100s", cp);
+ free(cp);
return 0;
}
@@ -408,25 +425,25 @@ _ssh_exchange_banner(struct ssh *ssh)
r = 0;
if (kex->server) {
- if (kex->server_version_string == NULL)
- r = _ssh_send_banner(ssh, &kex->server_version_string);
+ if (sshbuf_len(ssh->kex->server_version) == 0)
+ r = _ssh_send_banner(ssh, ssh->kex->server_version);
if (r == 0 &&
- kex->server_version_string != NULL &&
- kex->client_version_string == NULL)
- r = _ssh_read_banner(ssh, &kex->client_version_string);
+ sshbuf_len(ssh->kex->server_version) != 0 &&
+ sshbuf_len(ssh->kex->client_version) == 0)
+ r = _ssh_read_banner(ssh, ssh->kex->client_version);
} else {
- if (kex->server_version_string == NULL)
- r = _ssh_read_banner(ssh, &kex->server_version_string);
+ if (sshbuf_len(ssh->kex->server_version) == 0)
+ r = _ssh_read_banner(ssh, ssh->kex->server_version);
if (r == 0 &&
- kex->server_version_string != NULL &&
- kex->client_version_string == NULL)
- r = _ssh_send_banner(ssh, &kex->client_version_string);
+ sshbuf_len(ssh->kex->server_version) != 0 &&
+ sshbuf_len(ssh->kex->client_version) == 0)
+ r = _ssh_send_banner(ssh, ssh->kex->client_version);
}
if (r != 0)
return r;
/* start initial kex as soon as we have exchanged the banners */
- if (kex->server_version_string != NULL &&
- kex->client_version_string != NULL) {
+ if (sshbuf_len(ssh->kex->server_version) != 0 &&
+ sshbuf_len(ssh->kex->client_version) != 0) {
if ((r = _ssh_order_hostkeyalgs(ssh)) != 0 ||
(r = kex_send_kexinit(ssh)) != 0)
return r;
@@ -532,9 +549,10 @@ _ssh_order_hostkeyalgs(struct ssh *ssh)
}
int
-_ssh_host_key_sign(struct sshkey *privkey, struct sshkey *pubkey,
- u_char **signature, size_t *slen, const u_char *data, size_t dlen,
- const char *alg, u_int compat)
+_ssh_host_key_sign(struct ssh *ssh, struct sshkey *privkey,
+ struct sshkey *pubkey, u_char **signature, size_t *slen,
+ const u_char *data, size_t dlen, const char *alg)
{
- return sshkey_sign(privkey, signature, slen, data, dlen, alg, compat);
+ return sshkey_sign(privkey, signature, slen, data, dlen,
+ alg, ssh->compat);
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-08-05 06:46:23 +0000