/* Copyright (C) Sara Golemon <sarag@libssh2.org>
* Copyright (C) Daniel Stenberg
* All rights reserved.
*
* Redistribution and use in source and binary forms,
* with or without modification, are permitted provided
* that the following conditions are met:
*
* Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
*
* Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* Neither the name of the copyright holder nor the names
* of any other contributors may be used to endorse or
* promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
* USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include "libssh2_priv.h"
/* Needed for struct iovec on some platforms */
#ifdef HAVE_SYS_UIO_H
#include <sys/uio.h>
#endif
#if LIBSSH2_RSA
/* ***********
* ssh-rsa *
*********** */
static int hostkey_method_ssh_rsa_dtor(LIBSSH2_SESSION * session,
void **abstract);
/*
* hostkey_method_ssh_rsa_init
*
* Initialize the server hostkey working area with e/n pair
*/
static int
hostkey_method_ssh_rsa_init(LIBSSH2_SESSION * session,
const unsigned char *hostkey_data,
size_t hostkey_data_len,
void **abstract)
{
libssh2_rsa_ctx *rsactx;
unsigned char *e, *n, *type;
size_t e_len, n_len, type_len;
struct string_buf buf;
if(*abstract) {
hostkey_method_ssh_rsa_dtor(session, abstract);
*abstract = NULL;
}
if(hostkey_data_len < 19) {
_libssh2_debug((session, LIBSSH2_TRACE_ERROR,
"host key length too short"));
return -1;
}
buf.data = (unsigned char *)hostkey_data;
buf.dataptr = buf.data;
buf.len = hostkey_data_len;
if(_libssh2_get_string(&buf, &type, &type_len)) {
return -1;
}
/* we accept one of 3 header types */
#if LIBSSH2_RSA_SHA1
if(type_len == 7 && strncmp("ssh-rsa", (char *)type, 7) == 0) {
/* ssh-rsa */
}
else
#endif
#if LIBSSH2_RSA_SHA2
if(type_len == 12 && strncmp("rsa-sha2-256", (char *)type, 12) == 0) {
/* rsa-sha2-256 */
}
else if(type_len == 12 && strncmp("rsa-sha2-512", (char *)type, 12) == 0) {
/* rsa-sha2-512 */
}
else
#endif
{
_libssh2_debug((session, LIBSSH2_TRACE_ERROR,
"unexpected rsa type: %.*s", type_len, type));
return -1;
}
if(_libssh2_get_string(&buf, &e, &e_len))
return -1;
if(_libssh2_get_string(&buf, &n, &n_len))
return -1;
if(!_libssh2_eob(&buf))
return -1;
if(_libssh2_rsa_new(&rsactx,
e, (unsigned long)e_len,
n, (unsigned long)n_len,
NULL, 0, NULL, 0, NULL, 0,
NULL, 0, NULL, 0, NULL, 0)) {
return -1;
}
*abstract = rsactx;
return 0;
}
/*
* hostkey_method_ssh_rsa_initPEM
*
* Load a Private Key from a PEM file
*/
static int
hostkey_method_ssh_rsa_initPEM(LIBSSH2_SESSION * session,
const char *privkeyfile,
unsigned const char *passphrase,
void **abstract)
{
libssh2_rsa_ctx *rsactx;
int ret;
if(*abstract) {
hostkey_method_ssh_rsa_dtor(session, abstract);
*abstract = NULL;
}
ret = _libssh2_rsa_new_private(&rsactx, session, privkeyfile, passphrase);
if(ret) {
return -1;
}
*abstract = rsactx;
return 0;
}
/*
* hostkey_method_ssh_rsa_initPEMFromMemory
*
* Load a Private Key from a memory
*/
static int
hostkey_method_ssh_rsa_initPEMFromMemory(LIBSSH2_SESSION * session,
const char *privkeyfiledata,
size_t privkeyfiledata_len,
unsigned const char *passphrase,
void **abstract)
{
libssh2_rsa_ctx *rsactx;
int ret;
if(*abstract) {
hostkey_method_ssh_rsa_dtor(session, abstract);
*abstract = NULL;
}
ret = _libssh2_rsa_new_private_frommemory(&rsactx, session,
privkeyfiledata,
privkeyfiledata_len, passphrase);
if(ret) {
return -1;
}
*abstract = rsactx;
return 0;
}
#if LIBSSH2_RSA_SHA1
/*
* hostkey_method_ssh_rsa_sign
*
* Verify signature created by remote
*/
static int
hostkey_method_ssh_rsa_sig_verify(LIBSSH2_SESSION * session,
const unsigned char *sig,
size_t sig_len,
const unsigned char *m,
size_t m_len, void **abstract)
{
libssh2_rsa_ctx *rsactx = (libssh2_rsa_ctx *) (*abstract);
(void)session;
/* Skip past keyname_len(4) + keyname(7){"ssh-rsa"} + signature_len(4) */
if(sig_len < 15)
return -1;
sig += 15;
sig_len -= 15;
return _libssh2_rsa_sha1_verify(rsactx, sig, sig_len, m, m_len);
}
/*
* hostkey_method_ssh_rsa_signv
*
* Construct a signature from an array of vectors
*/
static int
hostkey_method_ssh_rsa_signv(LIBSSH2_SESSION * session,
unsigned char **signature,
size_t *signature_len,
int veccount,
const struct iovec datavec[],
void **abstract)
{
libssh2_rsa_ctx *rsactx = (libssh2_rsa_ctx *) (*abstract);
#ifdef _libssh2_rsa_sha1_signv
return _libssh2_rsa_sha1_signv(session, signature, signature_len,
veccount, datavec, rsactx);
#else
int ret;
int i;
unsigned char hash[SHA_DIGEST_LENGTH];
libssh2_sha1_ctx ctx;
(void)libssh2_sha1_init(&ctx);
for(i = 0; i < veccount; i++) {
libssh2_sha1_update(ctx, datavec[i].iov_base, datavec[i].iov_len);
}
libssh2_sha1_final(ctx, hash);
ret = _libssh2_rsa_sha1_sign(session, rsactx, hash, SHA_DIGEST_LENGTH,
signature, signature_len);
if(ret) {
return -1;
}
return 0;
#endif
}
#endif
/*
* hostkey_method_ssh_rsa_sha2_256_sig_verify
*
* Verify signature created by remote
*/
#if LIBSSH2_RSA_SHA2
static int
hostkey_method_ssh_rsa_sha2_256_sig_verify(LIBSSH2_SESSION * session,
const unsigned char *sig,
size_t sig_len,
const unsigned char *m,
size_t m_len, void **abstract)
{
libssh2_rsa_ctx *rsactx = (libssh2_rsa_ctx *) (*abstract);
(void)session;
/* Skip past keyname_len(4) + keyname(12){"rsa-sha2-256"} +
signature_len(4) */
if(sig_len < 20)
return -1;
sig += 20;
sig_len -= 20;
return _libssh2_rsa_sha2_verify(rsactx, SHA256_DIGEST_LENGTH, sig, sig_len,
m, m_len);
}
/*
* hostkey_method_ssh_rsa_sha2_256_signv
*
* Construct a signature from an array of vectors
*/
static int
hostkey_method_ssh_rsa_sha2_256_signv(LIBSSH2_SESSION * session,
unsigned char **signature,
size_t *signature_len,
int veccount,
const struct iovec datavec[],
void **abstract)
{
libssh2_rsa_ctx *rsactx = (libssh2_rsa_ctx *) (*abstract);
#ifdef _libssh2_rsa_sha2_256_signv
return _libssh2_rsa_sha2_256_signv(session, signature, signature_len,
veccount, datavec, rsactx);
#else
int ret;
int i;
unsigned char hash[SHA256_DIGEST_LENGTH];
libssh2_sha256_ctx ctx;
if(!libssh2_sha256_init(&ctx)) {
return -1;
}
for(i = 0; i < veccount; i++) {
libssh2_sha256_update(ctx, datavec[i].iov_base, datavec[i].iov_len);
}
libssh2_sha256_final(ctx, hash);
ret = _libssh2_rsa_sha2_sign(session, rsactx, hash, SHA256_DIGEST_LENGTH,
signature, signature_len);
if(ret) {
return -1;
}
return 0;
#endif
}
/*
* hostkey_method_ssh_rsa_sha2_512_sig_verify
*
* Verify signature created by remote
*/
static int
hostkey_method_ssh_rsa_sha2_512_sig_verify(LIBSSH2_SESSION * session,
const unsigned char *sig,
size_t sig_len,
const unsigned char *m,
size_t m_len, void **abstract)
{
libssh2_rsa_ctx *rsactx = (libssh2_rsa_ctx *) (*abstract);
(void)session;
/* Skip past keyname_len(4) + keyname(12){"rsa-sha2-512"} +
signature_len(4) */
if(sig_len < 20)
return -1;
sig += 20;
sig_len -= 20;
return _libssh2_rsa_sha2_verify(rsactx, SHA512_DIGEST_LENGTH, sig,
sig_len, m, m_len);
}
/*
* hostkey_method_ssh_rsa_sha2_512_signv
*
* Construct a signature from an array of vectors
*/
static int
hostkey_method_ssh_rsa_sha2_512_signv(LIBSSH2_SESSION * session,
unsigned char **signature,
size_t *signature_len,
int veccount,
const struct iovec datavec[],
void **abstract)
{
libssh2_rsa_ctx *rsactx = (libssh2_rsa_ctx *) (*abstract);
#ifdef _libssh2_rsa_sha2_512_signv
return _libssh2_rsa_sha2_512_signv(session, signature, signature_len,
veccount, datavec, rsactx);
#else
int ret;
int i;
unsigned char hash[SHA512_DIGEST_LENGTH];
libssh2_sha512_ctx ctx;
if(!libssh2_sha512_init(&ctx)) {
return -1;
}
for(i = 0; i < veccount; i++) {
libssh2_sha512_update(ctx, datavec[i].iov_base, datavec[i].iov_len);
}
libssh2_sha512_final(ctx, hash);
ret = _libssh2_rsa_sha2_sign(session, rsactx, hash, SHA512_DIGEST_LENGTH,
signature, signature_len);
if(ret) {
return -1;
}
return 0;
#endif
}
#endif /* LIBSSH2_RSA_SHA2 */
/*
* hostkey_method_ssh_rsa_dtor
*
* Shutdown the hostkey
*/
static int
hostkey_method_ssh_rsa_dtor(LIBSSH2_SESSION * session, void **abstract)
{
libssh2_rsa_ctx *rsactx = (libssh2_rsa_ctx *) (*abstract);
(void)session;
_libssh2_rsa_free(rsactx);
*abstract = NULL;
return 0;
}
#if LIBSSH2_RSA_SHA1
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ssh_rsa = {
"ssh-rsa",
SHA_DIGEST_LENGTH,
hostkey_method_ssh_rsa_init,
hostkey_method_ssh_rsa_initPEM,
hostkey_method_ssh_rsa_initPEMFromMemory,
hostkey_method_ssh_rsa_sig_verify,
hostkey_method_ssh_rsa_signv,
NULL, /* encrypt */
hostkey_method_ssh_rsa_dtor,
};
#endif /* LIBSSH2_RSA_SHA1 */
#if LIBSSH2_RSA_SHA2
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ssh_rsa_sha2_256 = {
"rsa-sha2-256",
SHA256_DIGEST_LENGTH,
hostkey_method_ssh_rsa_init,
hostkey_method_ssh_rsa_initPEM,
hostkey_method_ssh_rsa_initPEMFromMemory,
hostkey_method_ssh_rsa_sha2_256_sig_verify,
hostkey_method_ssh_rsa_sha2_256_signv,
NULL, /* encrypt */
hostkey_method_ssh_rsa_dtor,
};
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ssh_rsa_sha2_512 = {
"rsa-sha2-512",
SHA512_DIGEST_LENGTH,
hostkey_method_ssh_rsa_init,
hostkey_method_ssh_rsa_initPEM,
hostkey_method_ssh_rsa_initPEMFromMemory,
hostkey_method_ssh_rsa_sha2_512_sig_verify,
hostkey_method_ssh_rsa_sha2_512_signv,
NULL, /* encrypt */
hostkey_method_ssh_rsa_dtor,
};
#endif /* LIBSSH2_RSA_SHA2 */
#if LIBSSH2_RSA_SHA1
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ssh_rsa_cert = {
"ssh-rsa-cert-v01@openssh.com",
SHA_DIGEST_LENGTH,
NULL,
hostkey_method_ssh_rsa_initPEM,
hostkey_method_ssh_rsa_initPEMFromMemory,
NULL,
hostkey_method_ssh_rsa_signv,
NULL, /* encrypt */
hostkey_method_ssh_rsa_dtor,
};
#endif /* LIBSSH2_RSA_SHA1 */
#endif /* LIBSSH2_RSA */
#if LIBSSH2_DSA
/* ***********
* ssh-dss *
*********** */
static int hostkey_method_ssh_dss_dtor(LIBSSH2_SESSION * session,
void **abstract);
/*
* hostkey_method_ssh_dss_init
*
* Initialize the server hostkey working area with p/q/g/y set
*/
static int
hostkey_method_ssh_dss_init(LIBSSH2_SESSION * session,
const unsigned char *hostkey_data,
size_t hostkey_data_len,
void **abstract)
{
libssh2_dsa_ctx *dsactx;
unsigned char *p, *q, *g, *y;
size_t p_len, q_len, g_len, y_len;
struct string_buf buf;
if(*abstract) {
hostkey_method_ssh_dss_dtor(session, abstract);
*abstract = NULL;
}
if(hostkey_data_len < 27) {
_libssh2_debug((session, LIBSSH2_TRACE_ERROR,
"host key length too short"));
return -1;
}
buf.data = (unsigned char *)hostkey_data;
buf.dataptr = buf.data;
buf.len = hostkey_data_len;
if(_libssh2_match_string(&buf, "ssh-dss"))
return -1;
if(_libssh2_get_string(&buf, &p, &p_len))
return -1;
if(_libssh2_get_string(&buf, &q, &q_len))
return -1;
if(_libssh2_get_string(&buf, &g, &g_len))
return -1;
if(_libssh2_get_string(&buf, &y, &y_len))
return -1;
if(!_libssh2_eob(&buf))
return -1;
if(_libssh2_dsa_new(&dsactx,
p, (unsigned long)p_len,
q, (unsigned long)q_len,
g, (unsigned long)g_len,
y, (unsigned long)y_len,
NULL, 0)) {
return -1;
}
*abstract = dsactx;
return 0;
}
/*
* hostkey_method_ssh_dss_initPEM
*
* Load a Private Key from a PEM file
*/
static int
hostkey_method_ssh_dss_initPEM(LIBSSH2_SESSION * session,
const char *privkeyfile,
unsigned const char *passphrase,
void **abstract)
{
libssh2_dsa_ctx *dsactx;
int ret;
if(*abstract) {
hostkey_method_ssh_dss_dtor(session, abstract);
*abstract = NULL;
}
ret = _libssh2_dsa_new_private(&dsactx, session, privkeyfile, passphrase);
if(ret) {
return -1;
}
*abstract = dsactx;
return 0;
}
/*
* hostkey_method_ssh_dss_initPEMFromMemory
*
* Load a Private Key from memory
*/
static int
hostkey_method_ssh_dss_initPEMFromMemory(LIBSSH2_SESSION * session,
const char *privkeyfiledata,
size_t privkeyfiledata_len,
unsigned const char *passphrase,
void **abstract)
{
libssh2_dsa_ctx *dsactx;
int ret;
if(*abstract) {
hostkey_method_ssh_dss_dtor(session, abstract);
*abstract = NULL;
}
ret = _libssh2_dsa_new_private_frommemory(&dsactx, session,
privkeyfiledata,
privkeyfiledata_len, passphrase);
if(ret) {
return -1;
}
*abstract = dsactx;
return 0;
}
/*
* libssh2_hostkey_method_ssh_dss_sign
*
* Verify signature created by remote
*/
static int
hostkey_method_ssh_dss_sig_verify(LIBSSH2_SESSION * session,
const unsigned char *sig,
size_t sig_len,
const unsigned char *m,
size_t m_len, void **abstract)
{
libssh2_dsa_ctx *dsactx = (libssh2_dsa_ctx *) (*abstract);
/* Skip past keyname_len(4) + keyname(7){"ssh-dss"} + signature_len(4) */
if(sig_len != 55) {
return _libssh2_error(session, LIBSSH2_ERROR_PROTO,
"Invalid DSS signature length");
}
sig += 15;
sig_len -= 15;
return _libssh2_dsa_sha1_verify(dsactx, sig, m, m_len);
}
/*
* hostkey_method_ssh_dss_signv
*
* Construct a signature from an array of vectors
*/
static int
hostkey_method_ssh_dss_signv(LIBSSH2_SESSION * session,
unsigned char **signature,
size_t *signature_len,
int veccount,
const struct iovec datavec[],
void **abstract)
{
libssh2_dsa_ctx *dsactx = (libssh2_dsa_ctx *) (*abstract);
unsigned char hash[SHA_DIGEST_LENGTH];
libssh2_sha1_ctx ctx;
int i;
*signature = LIBSSH2_CALLOC(session, 2 * SHA_DIGEST_LENGTH);
if(!*signature) {
return -1;
}
*signature_len = 2 * SHA_DIGEST_LENGTH;
(void)libssh2_sha1_init(&ctx);
for(i = 0; i < veccount; i++) {
libssh2_sha1_update(ctx, datavec[i].iov_base, datavec[i].iov_len);
}
libssh2_sha1_final(ctx, hash);
if(_libssh2_dsa_sha1_sign(dsactx, hash, SHA_DIGEST_LENGTH, *signature)) {
LIBSSH2_FREE(session, *signature);
return -1;
}
return 0;
}
/*
* libssh2_hostkey_method_ssh_dss_dtor
*
* Shutdown the hostkey method
*/
static int
hostkey_method_ssh_dss_dtor(LIBSSH2_SESSION * session, void **abstract)
{
libssh2_dsa_ctx *dsactx = (libssh2_dsa_ctx *) (*abstract);
(void)session;
_libssh2_dsa_free(dsactx);
*abstract = NULL;
return 0;
}
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ssh_dss = {
"ssh-dss",
SHA_DIGEST_LENGTH,
hostkey_method_ssh_dss_init,
hostkey_method_ssh_dss_initPEM,
hostkey_method_ssh_dss_initPEMFromMemory,
hostkey_method_ssh_dss_sig_verify,
hostkey_method_ssh_dss_signv,
NULL, /* encrypt */
hostkey_method_ssh_dss_dtor,
};
#endif /* LIBSSH2_DSA */
#if LIBSSH2_ECDSA
/* ***********
* ecdsa-sha2-nistp256/384/521 *
*********** */
static int
hostkey_method_ssh_ecdsa_dtor(LIBSSH2_SESSION * session,
void **abstract);
/*
* hostkey_method_ssh_ecdsa_init
*
* Initialize the server hostkey working area with e/n pair
*/
static int
hostkey_method_ssh_ecdsa_init(LIBSSH2_SESSION * session,
const unsigned char *hostkey_data,
size_t hostkey_data_len,
void **abstract)
{
libssh2_ecdsa_ctx *ecdsactx = NULL;
unsigned char *type_str, *domain, *public_key;
size_t key_len, len;
libssh2_curve_type type;
struct string_buf buf;
if(abstract && *abstract) {
hostkey_method_ssh_ecdsa_dtor(session, abstract);
*abstract = NULL;
}
if(hostkey_data_len < 39) {
_libssh2_debug((session, LIBSSH2_TRACE_ERROR,
"host key length too short"));
return -1;
}
buf.data = (unsigned char *)hostkey_data;
buf.dataptr = buf.data;
buf.len = hostkey_data_len;
if(_libssh2_get_string(&buf, &type_str, &len) || len != 19)
return -1;
if(strncmp((char *) type_str, "ecdsa-sha2-nistp256", 19) == 0) {
type = LIBSSH2_EC_CURVE_NISTP256;
}
else if(strncmp((char *) type_str, "ecdsa-sha2-nistp384", 19) == 0) {
type = LIBSSH2_EC_CURVE_NISTP384;
}
else if(strncmp((char *) type_str, "ecdsa-sha2-nistp521", 19) == 0) {
type = LIBSSH2_EC_CURVE_NISTP521;
}
else {
return -1;
}
if(_libssh2_get_string(&buf, &domain, &len) || len != 8)
return -1;
if(type == LIBSSH2_EC_CURVE_NISTP256 &&
strncmp((char *)domain, "nistp256", 8) != 0) {
return -1;
}
else if(type == LIBSSH2_EC_CURVE_NISTP384 &&
strncmp((char *)domain, "nistp384", 8) != 0) {
return -1;
}
else if(type == LIBSSH2_EC_CURVE_NISTP521 &&
strncmp((char *)domain, "nistp521", 8) != 0) {
return -1;
}
/* public key */
if(_libssh2_get_string(&buf, &public_key, &key_len))
return -1;
if(!_libssh2_eob(&buf))
return -1;
if(_libssh2_ecdsa_curve_name_with_octal_new(&ecdsactx, public_key,
key_len, type))
return -1;
if(abstract)
*abstract = ecdsactx;
return 0;
}
/*
* hostkey_method_ssh_ecdsa_initPEM
*
* Load a Private Key from a PEM file
*/
static int
hostkey_method_ssh_ecdsa_initPEM(LIBSSH2_SESSION * session,
const char *privkeyfile,
unsigned const char *passphrase,
void **abstract)
{
libssh2_ecdsa_ctx *ec_ctx = NULL;
int ret;
if(abstract && *abstract) {
hostkey_method_ssh_ecdsa_dtor(session, abstract);
*abstract = NULL;
}
ret = _libssh2_ecdsa_new_private(&ec_ctx, session,
privkeyfile, passphrase);
if(abstract)
*abstract = ec_ctx;
return ret;
}
/*
* hostkey_method_ssh_ecdsa_initPEMFromMemory
*
* Load a Private Key from memory
*/
static int
hostkey_method_ssh_ecdsa_initPEMFromMemory(LIBSSH2_SESSION * session,
const char *privkeyfiledata,
size_t privkeyfiledata_len,
unsigned const char *passphrase,
void **abstract)
{
libssh2_ecdsa_ctx *ec_ctx = NULL;
int ret;
if(abstract && *abstract) {
hostkey_method_ssh_ecdsa_dtor(session, abstract);
*abstract = NULL;
}
ret = _libssh2_ecdsa_new_private_frommemory(&ec_ctx, session,
privkeyfiledata,
privkeyfiledata_len,
passphrase);
if(ret) {
return -1;
}
if(abstract)
*abstract = ec_ctx;
return 0;
}
/*
* hostkey_method_ecdsa_sig_verify
*
* Verify signature created by remote
*/
static int
hostkey_method_ssh_ecdsa_sig_verify(LIBSSH2_SESSION * session,
const unsigned char *sig,
size_t sig_len,
const unsigned char *m,
size_t m_len, void **abstract)
{
unsigned char *r, *s, *name;
size_t r_len, s_len, name_len;
uint32_t len;
struct string_buf buf;
libssh2_ecdsa_ctx *ctx = (libssh2_ecdsa_ctx *) (*abstract);
(void)session;
if(sig_len < 35)
return -1;
/* keyname_len(4) + keyname(19){"ecdsa-sha2-nistp256"} +
signature_len(4) */
buf.data = (unsigned char *)sig;
buf.dataptr = buf.data;
buf.len = sig_len;
if(_libssh2_get_string(&buf, &name, &name_len) || name_len != 19)
return -1;
if(_libssh2_get_u32(&buf, &len) != 0 || len < 8)
return -1;
if(_libssh2_get_string(&buf, &r, &r_len))
return -1;
if(_libssh2_get_string(&buf, &s, &s_len))
return -1;
return _libssh2_ecdsa_verify(ctx, r, r_len, s, s_len, m, m_len);
}
#define LIBSSH2_HOSTKEY_METHOD_EC_SIGNV_HASH(digest_type) \
do { \
unsigned char hash[SHA##digest_type##_DIGEST_LENGTH]; \
libssh2_sha##digest_type##_ctx ctx; \
int i; \
(void)libssh2_sha##digest_type##_init(&ctx); \
for(i = 0; i < veccount; i++) { \
libssh2_sha##digest_type##_update(ctx, datavec[i].iov_base, \
datavec[i].iov_len); \
} \
libssh2_sha##digest_type##_final(ctx, hash); \
ret = _libssh2_ecdsa_sign(session, ec_ctx, hash, \
SHA##digest_type##_DIGEST_LENGTH, \
signature, signature_len); \
} while(0)
/*
* hostkey_method_ecdsa_signv
*
* Construct a signature from an array of vectors
*/
static int
hostkey_method_ssh_ecdsa_signv(LIBSSH2_SESSION * session,
unsigned char **signature,
size_t *signature_len,
int veccount,
const struct iovec datavec[],
void **abstract)
{
libssh2_ecdsa_ctx *ec_ctx = (libssh2_ecdsa_ctx *) (*abstract);
libssh2_curve_type type = _libssh2_ecdsa_get_curve_type(ec_ctx);
int ret = 0;
if(type == LIBSSH2_EC_CURVE_NISTP256) {
LIBSSH2_HOSTKEY_METHOD_EC_SIGNV_HASH(256);
}
else if(type == LIBSSH2_EC_CURVE_NISTP384) {
LIBSSH2_HOSTKEY_METHOD_EC_SIGNV_HASH(384);
}
else if(type == LIBSSH2_EC_CURVE_NISTP521) {
LIBSSH2_HOSTKEY_METHOD_EC_SIGNV_HASH(512);
}
else {
return -1;
}
return ret;
}
/*
* hostkey_method_ssh_ecdsa_dtor
*
* Shutdown the hostkey by freeing EC_KEY context
*/
static int
hostkey_method_ssh_ecdsa_dtor(LIBSSH2_SESSION * session, void **abstract)
{
libssh2_ecdsa_ctx *keyctx = (libssh2_ecdsa_ctx *) (*abstract);
(void)session;
if(keyctx)
_libssh2_ecdsa_free(keyctx);
*abstract = NULL;
return 0;
}
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ecdsa_ssh_nistp256 = {
"ecdsa-sha2-nistp256",
SHA256_DIGEST_LENGTH,
hostkey_method_ssh_ecdsa_init,
hostkey_method_ssh_ecdsa_initPEM,
hostkey_method_ssh_ecdsa_initPEMFromMemory,
hostkey_method_ssh_ecdsa_sig_verify,
hostkey_method_ssh_ecdsa_signv,
NULL, /* encrypt */
hostkey_method_ssh_ecdsa_dtor,
};
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ecdsa_ssh_nistp384 = {
"ecdsa-sha2-nistp384",
SHA384_DIGEST_LENGTH,
hostkey_method_ssh_ecdsa_init,
hostkey_method_ssh_ecdsa_initPEM,
hostkey_method_ssh_ecdsa_initPEMFromMemory,
hostkey_method_ssh_ecdsa_sig_verify,
hostkey_method_ssh_ecdsa_signv,
NULL, /* encrypt */
hostkey_method_ssh_ecdsa_dtor,
};
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ecdsa_ssh_nistp521 = {
"ecdsa-sha2-nistp521",
SHA512_DIGEST_LENGTH,
hostkey_method_ssh_ecdsa_init,
hostkey_method_ssh_ecdsa_initPEM,
hostkey_method_ssh_ecdsa_initPEMFromMemory,
hostkey_method_ssh_ecdsa_sig_verify,
hostkey_method_ssh_ecdsa_signv,
NULL, /* encrypt */
hostkey_method_ssh_ecdsa_dtor,
};
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ecdsa_ssh_nistp256_cert = {
"ecdsa-sha2-nistp256-cert-v01@openssh.com",
SHA256_DIGEST_LENGTH,
NULL,
hostkey_method_ssh_ecdsa_initPEM,
hostkey_method_ssh_ecdsa_initPEMFromMemory,
NULL,
hostkey_method_ssh_ecdsa_signv,
NULL, /* encrypt */
hostkey_method_ssh_ecdsa_dtor,
};
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ecdsa_ssh_nistp384_cert = {
"ecdsa-sha2-nistp384-cert-v01@openssh.com",
SHA384_DIGEST_LENGTH,
NULL,
hostkey_method_ssh_ecdsa_initPEM,
hostkey_method_ssh_ecdsa_initPEMFromMemory,
NULL,
hostkey_method_ssh_ecdsa_signv,
NULL, /* encrypt */
hostkey_method_ssh_ecdsa_dtor,
};
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ecdsa_ssh_nistp521_cert = {
"ecdsa-sha2-nistp521-cert-v01@openssh.com",
SHA512_DIGEST_LENGTH,
NULL,
hostkey_method_ssh_ecdsa_initPEM,
hostkey_method_ssh_ecdsa_initPEMFromMemory,
NULL,
hostkey_method_ssh_ecdsa_signv,
NULL, /* encrypt */
hostkey_method_ssh_ecdsa_dtor,
};
#endif /* LIBSSH2_ECDSA */
#if LIBSSH2_ED25519
/* ***********
* ed25519 *
*********** */
static int hostkey_method_ssh_ed25519_dtor(LIBSSH2_SESSION * session,
void **abstract);
/*
* hostkey_method_ssh_ed25519_init
*
* Initialize the server hostkey working area with e/n pair
*/
static int
hostkey_method_ssh_ed25519_init(LIBSSH2_SESSION * session,
const unsigned char *hostkey_data,
size_t hostkey_data_len,
void **abstract)
{
size_t key_len;
unsigned char *key;
libssh2_ed25519_ctx *ctx = NULL;
struct string_buf buf;
if(*abstract) {
hostkey_method_ssh_ed25519_dtor(session, abstract);
*abstract = NULL;
}
if(hostkey_data_len < 19) {
_libssh2_debug((session, LIBSSH2_TRACE_ERROR,
"host key length too short"));
return -1;
}
buf.data = (unsigned char *)hostkey_data;
buf.dataptr = buf.data;
buf.len = hostkey_data_len;
if(_libssh2_match_string(&buf, "ssh-ed25519"))
return -1;
/* public key */
if(_libssh2_get_string(&buf, &key, &key_len))
return -1;
if(!_libssh2_eob(&buf))
return -1;
if(_libssh2_ed25519_new_public(&ctx, session, key, key_len) != 0) {
return -1;
}
*abstract = ctx;
return 0;
}
/*
* hostkey_method_ssh_ed25519_initPEM
*
* Load a Private Key from a PEM file
*/
static int
hostkey_method_ssh_ed25519_initPEM(LIBSSH2_SESSION * session,
const char *privkeyfile,
unsigned const char *passphrase,
void **abstract)
{
libssh2_ed25519_ctx *ec_ctx = NULL;
int ret;
if(*abstract) {
hostkey_method_ssh_ed25519_dtor(session, abstract);
*abstract = NULL;
}
ret = _libssh2_ed25519_new_private(&ec_ctx, session,
privkeyfile, passphrase);
if(ret) {
return -1;
}
*abstract = ec_ctx;
return ret;
}
/*
* hostkey_method_ssh_ed25519_initPEMFromMemory
*
* Load a Private Key from memory
*/
static int
hostkey_method_ssh_ed25519_initPEMFromMemory(LIBSSH2_SESSION * session,
const char *privkeyfiledata,
size_t privkeyfiledata_len,
unsigned const char *passphrase,
void **abstract)
{
libssh2_ed25519_ctx *ed_ctx = NULL;
int ret;
if(abstract && *abstract) {
hostkey_method_ssh_ed25519_dtor(session, abstract);
*abstract = NULL;
}
ret = _libssh2_ed25519_new_private_frommemory(&ed_ctx, session,
privkeyfiledata,
privkeyfiledata_len,
passphrase);
if(ret) {
return -1;
}
if(abstract)
*abstract = ed_ctx;
return 0;
}
/*
* hostkey_method_ssh_ed25519_sig_verify
*
* Verify signature created by remote
*/
static int
hostkey_method_ssh_ed25519_sig_verify(LIBSSH2_SESSION * session,
const unsigned char *sig,
size_t sig_len,
const unsigned char *m,
size_t m_len, void **abstract)
{
libssh2_ed25519_ctx *ctx = (libssh2_ed25519_ctx *) (*abstract);
(void)session;
if(sig_len < 19)
return -1;
/* Skip past keyname_len(4) + keyname(11){"ssh-ed25519"} +
signature_len(4) */
sig += 19;
sig_len -= 19;
if(sig_len != LIBSSH2_ED25519_SIG_LEN)
return -1;
return _libssh2_ed25519_verify(ctx, sig, sig_len, m, m_len);
}
/*
* hostkey_method_ssh_ed25519_signv
*
* Construct a signature from an array of vectors
*/
static int
hostkey_method_ssh_ed25519_signv(LIBSSH2_SESSION * session,
unsigned char **signature,
size_t *signature_len,
int veccount,
const struct iovec datavec[],
void **abstract)
{
libssh2_ed25519_ctx *ctx = (libssh2_ed25519_ctx *) (*abstract);
if(veccount != 1) {
return -1;
}
return _libssh2_ed25519_sign(ctx, session, signature, signature_len,
datavec[0].iov_base, datavec[0].iov_len);
}
/*
* hostkey_method_ssh_ed25519_dtor
*
* Shutdown the hostkey by freeing key context
*/
static int
hostkey_method_ssh_ed25519_dtor(LIBSSH2_SESSION * session, void **abstract)
{
libssh2_ed25519_ctx *keyctx = (libssh2_ed25519_ctx*) (*abstract);
(void)session;
if(keyctx)
_libssh2_ed25519_free(keyctx);
*abstract = NULL;
return 0;
}
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ssh_ed25519 = {
"ssh-ed25519",
SHA256_DIGEST_LENGTH,
hostkey_method_ssh_ed25519_init,
hostkey_method_ssh_ed25519_initPEM,
hostkey_method_ssh_ed25519_initPEMFromMemory,
hostkey_method_ssh_ed25519_sig_verify,
hostkey_method_ssh_ed25519_signv,
NULL, /* encrypt */
hostkey_method_ssh_ed25519_dtor,
};
static const LIBSSH2_HOSTKEY_METHOD hostkey_method_ssh_ed25519_cert = {
"ssh-ed25519-cert-v01@openssh.com",
SHA256_DIGEST_LENGTH,
hostkey_method_ssh_ed25519_init,
hostkey_method_ssh_ed25519_initPEM,
hostkey_method_ssh_ed25519_initPEMFromMemory,
hostkey_method_ssh_ed25519_sig_verify,
hostkey_method_ssh_ed25519_signv,
NULL, /* encrypt */
hostkey_method_ssh_ed25519_dtor,
};
#endif /* LIBSSH2_ED25519 */
static const LIBSSH2_HOSTKEY_METHOD *hostkey_methods[] = {
#if LIBSSH2_ECDSA
&hostkey_method_ecdsa_ssh_nistp256,
&hostkey_method_ecdsa_ssh_nistp384,
&hostkey_method_ecdsa_ssh_nistp521,
&hostkey_method_ecdsa_ssh_nistp256_cert,
&hostkey_method_ecdsa_ssh_nistp384_cert,
&hostkey_method_ecdsa_ssh_nistp521_cert,
#endif
#if LIBSSH2_ED25519
&hostkey_method_ssh_ed25519,
&hostkey_method_ssh_ed25519_cert,
#endif
#if LIBSSH2_RSA
#if LIBSSH2_RSA_SHA2
&hostkey_method_ssh_rsa_sha2_512,
&hostkey_method_ssh_rsa_sha2_256,
#endif /* LIBSSH2_RSA_SHA2 */
#if LIBSSH2_RSA_SHA1
&hostkey_method_ssh_rsa,
&hostkey_method_ssh_rsa_cert,
#endif /* LIBSSH2_RSA_SHA1 */
#endif /* LIBSSH2_RSA */
#if LIBSSH2_DSA
&hostkey_method_ssh_dss,
#endif /* LIBSSH2_DSA */
NULL
};
const LIBSSH2_HOSTKEY_METHOD **
libssh2_hostkey_methods(void)
{
return hostkey_methods;
}
/*
* libssh2_hostkey_hash
*
* Returns hash signature
* Returned buffer should NOT be freed
* Length of buffer is determined by hash type
* i.e. MD5 == 16, SHA1 == 20, SHA256 == 32
*/
LIBSSH2_API const char *
libssh2_hostkey_hash(LIBSSH2_SESSION * session, int hash_type)
{
switch(hash_type) {
#if LIBSSH2_MD5
case LIBSSH2_HOSTKEY_HASH_MD5:
return (session->server_hostkey_md5_valid)
? (char *) session->server_hostkey_md5
: NULL;
break;
#endif /* LIBSSH2_MD5 */
case LIBSSH2_HOSTKEY_HASH_SHA1:
return (session->server_hostkey_sha1_valid)
? (char *) session->server_hostkey_sha1
: NULL;
break;
case LIBSSH2_HOSTKEY_HASH_SHA256:
return (session->server_hostkey_sha256_valid)
? (char *) session->server_hostkey_sha256
: NULL;
break;
default:
return NULL;
}
}
static int hostkey_type(const unsigned char *hostkey, size_t len)
{
static const unsigned char rsa[] = {
0, 0, 0, 0x07, 's', 's', 'h', '-', 'r', 's', 'a'
};
static const unsigned char dss[] = {
0, 0, 0, 0x07, 's', 's', 'h', '-', 'd', 's', 's'
};
static const unsigned char ecdsa_256[] = {
0, 0, 0, 0x13, 'e', 'c', 'd', 's', 'a', '-', 's', 'h', 'a', '2', '-',
'n', 'i', 's', 't', 'p', '2', '5', '6'
};
static const unsigned char ecdsa_384[] = {
0, 0, 0, 0x13, 'e', 'c', 'd', 's', 'a', '-', 's', 'h', 'a', '2', '-',
'n', 'i', 's', 't', 'p', '3', '8', '4'
};
static const unsigned char ecdsa_521[] = {
0, 0, 0, 0x13, 'e', 'c', 'd', 's', 'a', '-', 's', 'h', 'a', '2', '-',
'n', 'i', 's', 't', 'p', '5', '2', '1'
};
static const unsigned char ed25519[] = {
0, 0, 0, 0x0b, 's', 's', 'h', '-', 'e', 'd', '2', '5', '5', '1', '9'
};
if(len < 11)
return LIBSSH2_HOSTKEY_TYPE_UNKNOWN;
if(!memcmp(rsa, hostkey, 11))
return LIBSSH2_HOSTKEY_TYPE_RSA;
if(!memcmp(dss, hostkey, 11))
return LIBSSH2_HOSTKEY_TYPE_DSS;
if(len < 15)
return LIBSSH2_HOSTKEY_TYPE_UNKNOWN;
if(!memcmp(ed25519, hostkey, 15))
return LIBSSH2_HOSTKEY_TYPE_ED25519;
if(len < 23)
return LIBSSH2_HOSTKEY_TYPE_UNKNOWN;
if(!memcmp(ecdsa_256, hostkey, 23))
return LIBSSH2_HOSTKEY_TYPE_ECDSA_256;
if(!memcmp(ecdsa_384, hostkey, 23))
return LIBSSH2_HOSTKEY_TYPE_ECDSA_384;
if(!memcmp(ecdsa_521, hostkey, 23))
return LIBSSH2_HOSTKEY_TYPE_ECDSA_521;
return LIBSSH2_HOSTKEY_TYPE_UNKNOWN;
}
/*
* libssh2_session_hostkey
*
* Returns the server key and length.
*
*/
LIBSSH2_API const char *
libssh2_session_hostkey(LIBSSH2_SESSION *session, size_t *len, int *type)
{
if(session->server_hostkey_len) {
if(len)
*len = session->server_hostkey_len;
if(type)
*type = hostkey_type(session->server_hostkey,
session->server_hostkey_len);
return (char *) session->server_hostkey;
}
if(len)
*len = 0;
return NULL;
}