Excerpts from the release notes: * ssh-agent(1): PKCS#11 modules must now be specified by their full paths. Previously dlopen(3) could search for them in system library directories. * ssh(1): allow forwarding Unix Domain sockets via ssh -W. * ssh(1): add support for configuration tags to ssh(1). This adds a ssh_config(5) "Tag" directive and corresponding "Match tag" predicate that may be used to select blocks of configuration similar to the pf.conf(5) keywords of the same name. * ssh(1): add a "match localnetwork" predicate. This allows matching on the addresses of available network interfaces and may be used to vary the effective client configuration based on network location. * ssh-agent(1): improve isolation between loaded PKCS#11 modules by running separate ssh-pkcs11-helpers for each loaded provider. * ssh-agent(1), ssh(1): improve defences against invalid PKCS#11 modules being loaded by checking that the requested module contains the required symbol before loading it. * ssh(1): don't incorrectly disable hostname canonicalization when CanonicalizeHostname=yes and ProxyJump was expicitly set to "none". bz3567 Full release notes at https://www.openssh.com/txt/release-9.4 Relnotes: Yes Sponsored by: The FreeBSD Foundation
913 lines
24 KiB
C
913 lines
24 KiB
C
/* $OpenBSD: auth-options.c,v 1.101 2023/07/14 07:44:21 dtucker Exp $ */
|
|
/*
|
|
* Copyright (c) 2018 Damien Miller <djm@mindrot.org>
|
|
*
|
|
* 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>
|
|
|
|
#include <stdlib.h>
|
|
#include <netdb.h>
|
|
#include <pwd.h>
|
|
#include <string.h>
|
|
#include <stdio.h>
|
|
#ifdef HAVE_STDINT_H
|
|
# include <stdint.h>
|
|
#endif
|
|
#include <stdarg.h>
|
|
#include <ctype.h>
|
|
#include <limits.h>
|
|
|
|
#include "openbsd-compat/sys-queue.h"
|
|
|
|
#include "xmalloc.h"
|
|
#include "ssherr.h"
|
|
#include "log.h"
|
|
#include "sshbuf.h"
|
|
#include "misc.h"
|
|
#include "sshkey.h"
|
|
#include "match.h"
|
|
#include "ssh2.h"
|
|
#include "auth-options.h"
|
|
|
|
static int
|
|
dup_strings(char ***dstp, size_t *ndstp, char **src, size_t nsrc)
|
|
{
|
|
char **dst;
|
|
size_t i, j;
|
|
|
|
*dstp = NULL;
|
|
*ndstp = 0;
|
|
|
|
if (nsrc == 0)
|
|
return 0;
|
|
if (nsrc >= SIZE_MAX / sizeof(*src) ||
|
|
(dst = calloc(nsrc, sizeof(*src))) == NULL)
|
|
return -1;
|
|
for (i = 0; i < nsrc; i++) {
|
|
if ((dst[i] = strdup(src[i])) == NULL) {
|
|
for (j = 0; j < i; j++)
|
|
free(dst[j]);
|
|
free(dst);
|
|
return -1;
|
|
}
|
|
}
|
|
/* success */
|
|
*dstp = dst;
|
|
*ndstp = nsrc;
|
|
return 0;
|
|
}
|
|
|
|
#define OPTIONS_CRITICAL 1
|
|
#define OPTIONS_EXTENSIONS 2
|
|
static int
|
|
cert_option_list(struct sshauthopt *opts, struct sshbuf *oblob,
|
|
u_int which, int crit)
|
|
{
|
|
char *command, *allowed;
|
|
char *name = NULL;
|
|
struct sshbuf *c = NULL, *data = NULL;
|
|
int r, ret = -1, found;
|
|
|
|
if ((c = sshbuf_fromb(oblob)) == NULL) {
|
|
error_f("sshbuf_fromb failed");
|
|
goto out;
|
|
}
|
|
|
|
while (sshbuf_len(c) > 0) {
|
|
sshbuf_free(data);
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|
data = NULL;
|
|
if ((r = sshbuf_get_cstring(c, &name, NULL)) != 0 ||
|
|
(r = sshbuf_froms(c, &data)) != 0) {
|
|
error_r(r, "Unable to parse certificate options");
|
|
goto out;
|
|
}
|
|
debug3("found certificate option \"%.100s\" len %zu",
|
|
name, sshbuf_len(data));
|
|
found = 0;
|
|
if ((which & OPTIONS_EXTENSIONS) != 0) {
|
|
if (strcmp(name, "no-touch-required") == 0) {
|
|
opts->no_require_user_presence = 1;
|
|
found = 1;
|
|
} else if (strcmp(name, "permit-X11-forwarding") == 0) {
|
|
opts->permit_x11_forwarding_flag = 1;
|
|
found = 1;
|
|
} else if (strcmp(name,
|
|
"permit-agent-forwarding") == 0) {
|
|
opts->permit_agent_forwarding_flag = 1;
|
|
found = 1;
|
|
} else if (strcmp(name,
|
|
"permit-port-forwarding") == 0) {
|
|
opts->permit_port_forwarding_flag = 1;
|
|
found = 1;
|
|
} else if (strcmp(name, "permit-pty") == 0) {
|
|
opts->permit_pty_flag = 1;
|
|
found = 1;
|
|
} else if (strcmp(name, "permit-user-rc") == 0) {
|
|
opts->permit_user_rc = 1;
|
|
found = 1;
|
|
}
|
|
}
|
|
if (!found && (which & OPTIONS_CRITICAL) != 0) {
|
|
if (strcmp(name, "verify-required") == 0) {
|
|
opts->require_verify = 1;
|
|
found = 1;
|
|
} else if (strcmp(name, "force-command") == 0) {
|
|
if ((r = sshbuf_get_cstring(data, &command,
|
|
NULL)) != 0) {
|
|
error_r(r, "Unable to parse \"%s\" "
|
|
"section", name);
|
|
goto out;
|
|
}
|
|
if (opts->force_command != NULL) {
|
|
error("Certificate has multiple "
|
|
"force-command options");
|
|
free(command);
|
|
goto out;
|
|
}
|
|
opts->force_command = command;
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|
found = 1;
|
|
} else if (strcmp(name, "source-address") == 0) {
|
|
if ((r = sshbuf_get_cstring(data, &allowed,
|
|
NULL)) != 0) {
|
|
error_r(r, "Unable to parse \"%s\" "
|
|
"section", name);
|
|
goto out;
|
|
}
|
|
if (opts->required_from_host_cert != NULL) {
|
|
error("Certificate has multiple "
|
|
"source-address options");
|
|
free(allowed);
|
|
goto out;
|
|
}
|
|
/* Check syntax */
|
|
if (addr_match_cidr_list(NULL, allowed) == -1) {
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|
error("Certificate source-address "
|
|
"contents invalid");
|
|
goto out;
|
|
}
|
|
opts->required_from_host_cert = allowed;
|
|
found = 1;
|
|
}
|
|
}
|
|
|
|
if (!found) {
|
|
if (crit) {
|
|
error("Certificate critical option \"%s\" "
|
|
"is not supported", name);
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|
goto out;
|
|
} else {
|
|
logit("Certificate extension \"%s\" "
|
|
"is not supported", name);
|
|
}
|
|
} else if (sshbuf_len(data) != 0) {
|
|
error("Certificate option \"%s\" corrupt "
|
|
"(extra data)", name);
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|
goto out;
|
|
}
|
|
free(name);
|
|
name = NULL;
|
|
}
|
|
/* successfully parsed all options */
|
|
ret = 0;
|
|
|
|
out:
|
|
free(name);
|
|
sshbuf_free(data);
|
|
sshbuf_free(c);
|
|
return ret;
|
|
}
|
|
|
|
struct sshauthopt *
|
|
sshauthopt_new(void)
|
|
{
|
|
struct sshauthopt *ret;
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|
|
|
if ((ret = calloc(1, sizeof(*ret))) == NULL)
|
|
return NULL;
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|
ret->force_tun_device = -1;
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|
return ret;
|
|
}
|
|
|
|
void
|
|
sshauthopt_free(struct sshauthopt *opts)
|
|
{
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|
size_t i;
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|
|
|
if (opts == NULL)
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|
return;
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|
|
|
free(opts->cert_principals);
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|
free(opts->force_command);
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|
free(opts->required_from_host_cert);
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|
free(opts->required_from_host_keys);
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|
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|
for (i = 0; i < opts->nenv; i++)
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|
free(opts->env[i]);
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free(opts->env);
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|
for (i = 0; i < opts->npermitopen; i++)
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free(opts->permitopen[i]);
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free(opts->permitopen);
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|
for (i = 0; i < opts->npermitlisten; i++)
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free(opts->permitlisten[i]);
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|
free(opts->permitlisten);
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|
|
|
freezero(opts, sizeof(*opts));
|
|
}
|
|
|
|
struct sshauthopt *
|
|
sshauthopt_new_with_keys_defaults(void)
|
|
{
|
|
struct sshauthopt *ret = NULL;
|
|
|
|
if ((ret = sshauthopt_new()) == NULL)
|
|
return NULL;
|
|
|
|
/* Defaults for authorized_keys flags */
|
|
ret->permit_port_forwarding_flag = 1;
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|
ret->permit_agent_forwarding_flag = 1;
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|
ret->permit_x11_forwarding_flag = 1;
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|
ret->permit_pty_flag = 1;
|
|
ret->permit_user_rc = 1;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Parse and record a permitopen/permitlisten directive.
|
|
* Return 0 on success. Return -1 on failure and sets *errstrp to error reason.
|
|
*/
|
|
static int
|
|
handle_permit(const char **optsp, int allow_bare_port,
|
|
char ***permitsp, size_t *npermitsp, const char **errstrp)
|
|
{
|
|
char *opt, *tmp, *cp, *host, **permits = *permitsp;
|
|
size_t npermits = *npermitsp;
|
|
const char *errstr = "unknown error";
|
|
|
|
if (npermits > SSH_AUTHOPT_PERMIT_MAX) {
|
|
*errstrp = "too many permission directives";
|
|
return -1;
|
|
}
|
|
if ((opt = opt_dequote(optsp, &errstr)) == NULL) {
|
|
return -1;
|
|
}
|
|
if (allow_bare_port && strchr(opt, ':') == NULL) {
|
|
/*
|
|
* Allow a bare port number in permitlisten to indicate a
|
|
* listen_host wildcard.
|
|
*/
|
|
if (asprintf(&tmp, "*:%s", opt) == -1) {
|
|
free(opt);
|
|
*errstrp = "memory allocation failed";
|
|
return -1;
|
|
}
|
|
free(opt);
|
|
opt = tmp;
|
|
}
|
|
if ((tmp = strdup(opt)) == NULL) {
|
|
free(opt);
|
|
*errstrp = "memory allocation failed";
|
|
return -1;
|
|
}
|
|
cp = tmp;
|
|
/* validate syntax before recording it. */
|
|
host = hpdelim2(&cp, NULL);
|
|
if (host == NULL || strlen(host) >= NI_MAXHOST) {
|
|
free(tmp);
|
|
free(opt);
|
|
*errstrp = "invalid permission hostname";
|
|
return -1;
|
|
}
|
|
/*
|
|
* don't want to use permitopen_port to avoid
|
|
* dependency on channels.[ch] here.
|
|
*/
|
|
if (cp == NULL ||
|
|
(strcmp(cp, "*") != 0 && a2port(cp) <= 0)) {
|
|
free(tmp);
|
|
free(opt);
|
|
*errstrp = "invalid permission port";
|
|
return -1;
|
|
}
|
|
/* XXX - add streamlocal support */
|
|
free(tmp);
|
|
/* Record it */
|
|
if ((permits = recallocarray(permits, npermits, npermits + 1,
|
|
sizeof(*permits))) == NULL) {
|
|
free(opt);
|
|
/* NB. don't update *permitsp if alloc fails */
|
|
*errstrp = "memory allocation failed";
|
|
return -1;
|
|
}
|
|
permits[npermits++] = opt;
|
|
*permitsp = permits;
|
|
*npermitsp = npermits;
|
|
return 0;
|
|
}
|
|
|
|
struct sshauthopt *
|
|
sshauthopt_parse(const char *opts, const char **errstrp)
|
|
{
|
|
char **oarray, *opt, *cp, *tmp;
|
|
int r;
|
|
struct sshauthopt *ret = NULL;
|
|
const char *errstr = "unknown error";
|
|
uint64_t valid_before;
|
|
size_t i, l;
|
|
|
|
if (errstrp != NULL)
|
|
*errstrp = NULL;
|
|
if ((ret = sshauthopt_new_with_keys_defaults()) == NULL)
|
|
goto alloc_fail;
|
|
|
|
if (opts == NULL)
|
|
return ret;
|
|
|
|
while (*opts && *opts != ' ' && *opts != '\t') {
|
|
/* flag options */
|
|
if ((r = opt_flag("restrict", 0, &opts)) != -1) {
|
|
ret->restricted = 1;
|
|
ret->permit_port_forwarding_flag = 0;
|
|
ret->permit_agent_forwarding_flag = 0;
|
|
ret->permit_x11_forwarding_flag = 0;
|
|
ret->permit_pty_flag = 0;
|
|
ret->permit_user_rc = 0;
|
|
} else if ((r = opt_flag("cert-authority", 0, &opts)) != -1) {
|
|
ret->cert_authority = r;
|
|
} else if ((r = opt_flag("port-forwarding", 1, &opts)) != -1) {
|
|
ret->permit_port_forwarding_flag = r == 1;
|
|
} else if ((r = opt_flag("agent-forwarding", 1, &opts)) != -1) {
|
|
ret->permit_agent_forwarding_flag = r == 1;
|
|
} else if ((r = opt_flag("x11-forwarding", 1, &opts)) != -1) {
|
|
ret->permit_x11_forwarding_flag = r == 1;
|
|
} else if ((r = opt_flag("touch-required", 1, &opts)) != -1) {
|
|
ret->no_require_user_presence = r != 1; /* NB. flip */
|
|
} else if ((r = opt_flag("verify-required", 1, &opts)) != -1) {
|
|
ret->require_verify = r == 1;
|
|
} else if ((r = opt_flag("pty", 1, &opts)) != -1) {
|
|
ret->permit_pty_flag = r == 1;
|
|
} else if ((r = opt_flag("user-rc", 1, &opts)) != -1) {
|
|
ret->permit_user_rc = r == 1;
|
|
} else if (opt_match(&opts, "command")) {
|
|
if (ret->force_command != NULL) {
|
|
errstr = "multiple \"command\" clauses";
|
|
goto fail;
|
|
}
|
|
ret->force_command = opt_dequote(&opts, &errstr);
|
|
if (ret->force_command == NULL)
|
|
goto fail;
|
|
} else if (opt_match(&opts, "principals")) {
|
|
if (ret->cert_principals != NULL) {
|
|
errstr = "multiple \"principals\" clauses";
|
|
goto fail;
|
|
}
|
|
ret->cert_principals = opt_dequote(&opts, &errstr);
|
|
if (ret->cert_principals == NULL)
|
|
goto fail;
|
|
} else if (opt_match(&opts, "from")) {
|
|
if (ret->required_from_host_keys != NULL) {
|
|
errstr = "multiple \"from\" clauses";
|
|
goto fail;
|
|
}
|
|
ret->required_from_host_keys = opt_dequote(&opts,
|
|
&errstr);
|
|
if (ret->required_from_host_keys == NULL)
|
|
goto fail;
|
|
} else if (opt_match(&opts, "expiry-time")) {
|
|
if ((opt = opt_dequote(&opts, &errstr)) == NULL)
|
|
goto fail;
|
|
if (parse_absolute_time(opt, &valid_before) != 0 ||
|
|
valid_before == 0) {
|
|
free(opt);
|
|
errstr = "invalid expires time";
|
|
goto fail;
|
|
}
|
|
free(opt);
|
|
if (ret->valid_before == 0 ||
|
|
valid_before < ret->valid_before)
|
|
ret->valid_before = valid_before;
|
|
} else if (opt_match(&opts, "environment")) {
|
|
if (ret->nenv > SSH_AUTHOPT_ENV_MAX) {
|
|
errstr = "too many environment strings";
|
|
goto fail;
|
|
}
|
|
if ((opt = opt_dequote(&opts, &errstr)) == NULL)
|
|
goto fail;
|
|
/* env name must be alphanumeric and followed by '=' */
|
|
if ((tmp = strchr(opt, '=')) == NULL) {
|
|
free(opt);
|
|
errstr = "invalid environment string";
|
|
goto fail;
|
|
}
|
|
if ((cp = strdup(opt)) == NULL) {
|
|
free(opt);
|
|
goto alloc_fail;
|
|
}
|
|
l = (size_t)(tmp - opt);
|
|
cp[l] = '\0'; /* truncate at '=' */
|
|
if (!valid_env_name(cp)) {
|
|
free(cp);
|
|
free(opt);
|
|
errstr = "invalid environment string";
|
|
goto fail;
|
|
}
|
|
/* Check for duplicates; XXX O(n*log(n)) */
|
|
for (i = 0; i < ret->nenv; i++) {
|
|
if (strncmp(ret->env[i], cp, l) == 0 &&
|
|
ret->env[i][l] == '=')
|
|
break;
|
|
}
|
|
free(cp);
|
|
/* First match wins */
|
|
if (i >= ret->nenv) {
|
|
/* Append it. */
|
|
oarray = ret->env;
|
|
if ((ret->env = recallocarray(ret->env,
|
|
ret->nenv, ret->nenv + 1,
|
|
sizeof(*ret->env))) == NULL) {
|
|
free(opt);
|
|
/* put it back for cleanup */
|
|
ret->env = oarray;
|
|
goto alloc_fail;
|
|
}
|
|
ret->env[ret->nenv++] = opt;
|
|
opt = NULL; /* transferred */
|
|
}
|
|
free(opt);
|
|
} else if (opt_match(&opts, "permitopen")) {
|
|
if (handle_permit(&opts, 0, &ret->permitopen,
|
|
&ret->npermitopen, &errstr) != 0)
|
|
goto fail;
|
|
} else if (opt_match(&opts, "permitlisten")) {
|
|
if (handle_permit(&opts, 1, &ret->permitlisten,
|
|
&ret->npermitlisten, &errstr) != 0)
|
|
goto fail;
|
|
} else if (opt_match(&opts, "tunnel")) {
|
|
if ((opt = opt_dequote(&opts, &errstr)) == NULL)
|
|
goto fail;
|
|
ret->force_tun_device = a2tun(opt, NULL);
|
|
free(opt);
|
|
if (ret->force_tun_device == SSH_TUNID_ERR) {
|
|
errstr = "invalid tun device";
|
|
goto fail;
|
|
}
|
|
}
|
|
/*
|
|
* Skip the comma, and move to the next option
|
|
* (or break out if there are no more).
|
|
*/
|
|
if (*opts == '\0' || *opts == ' ' || *opts == '\t')
|
|
break; /* End of options. */
|
|
/* Anything other than a comma is an unknown option */
|
|
if (*opts != ',') {
|
|
errstr = "unknown key option";
|
|
goto fail;
|
|
}
|
|
opts++;
|
|
if (*opts == '\0') {
|
|
errstr = "unexpected end-of-options";
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
/* success */
|
|
if (errstrp != NULL)
|
|
*errstrp = NULL;
|
|
return ret;
|
|
|
|
alloc_fail:
|
|
errstr = "memory allocation failed";
|
|
fail:
|
|
sshauthopt_free(ret);
|
|
if (errstrp != NULL)
|
|
*errstrp = errstr;
|
|
return NULL;
|
|
}
|
|
|
|
struct sshauthopt *
|
|
sshauthopt_from_cert(struct sshkey *k)
|
|
{
|
|
struct sshauthopt *ret;
|
|
|
|
if (k == NULL || !sshkey_type_is_cert(k->type) || k->cert == NULL ||
|
|
k->cert->type != SSH2_CERT_TYPE_USER)
|
|
return NULL;
|
|
|
|
if ((ret = sshauthopt_new()) == NULL)
|
|
return NULL;
|
|
|
|
/* Handle options and critical extensions separately */
|
|
if (cert_option_list(ret, k->cert->critical,
|
|
OPTIONS_CRITICAL, 1) == -1) {
|
|
sshauthopt_free(ret);
|
|
return NULL;
|
|
}
|
|
if (cert_option_list(ret, k->cert->extensions,
|
|
OPTIONS_EXTENSIONS, 0) == -1) {
|
|
sshauthopt_free(ret);
|
|
return NULL;
|
|
}
|
|
/* success */
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Merges "additional" options to "primary" and returns the result.
|
|
* NB. Some options from primary have primacy.
|
|
*/
|
|
struct sshauthopt *
|
|
sshauthopt_merge(const struct sshauthopt *primary,
|
|
const struct sshauthopt *additional, const char **errstrp)
|
|
{
|
|
struct sshauthopt *ret;
|
|
const char *errstr = "internal error";
|
|
const char *tmp;
|
|
|
|
if (errstrp != NULL)
|
|
*errstrp = NULL;
|
|
|
|
if ((ret = sshauthopt_new()) == NULL)
|
|
goto alloc_fail;
|
|
|
|
/* cert_authority and cert_principals are cleared in result */
|
|
|
|
/* Prefer access lists from primary. */
|
|
/* XXX err is both set and mismatch? */
|
|
tmp = primary->required_from_host_cert;
|
|
if (tmp == NULL)
|
|
tmp = additional->required_from_host_cert;
|
|
if (tmp != NULL && (ret->required_from_host_cert = strdup(tmp)) == NULL)
|
|
goto alloc_fail;
|
|
tmp = primary->required_from_host_keys;
|
|
if (tmp == NULL)
|
|
tmp = additional->required_from_host_keys;
|
|
if (tmp != NULL && (ret->required_from_host_keys = strdup(tmp)) == NULL)
|
|
goto alloc_fail;
|
|
|
|
/*
|
|
* force_tun_device, permitopen/permitlisten and environment all
|
|
* prefer the primary.
|
|
*/
|
|
ret->force_tun_device = primary->force_tun_device;
|
|
if (ret->force_tun_device == -1)
|
|
ret->force_tun_device = additional->force_tun_device;
|
|
if (primary->nenv > 0) {
|
|
if (dup_strings(&ret->env, &ret->nenv,
|
|
primary->env, primary->nenv) != 0)
|
|
goto alloc_fail;
|
|
} else if (additional->nenv) {
|
|
if (dup_strings(&ret->env, &ret->nenv,
|
|
additional->env, additional->nenv) != 0)
|
|
goto alloc_fail;
|
|
}
|
|
if (primary->npermitopen > 0) {
|
|
if (dup_strings(&ret->permitopen, &ret->npermitopen,
|
|
primary->permitopen, primary->npermitopen) != 0)
|
|
goto alloc_fail;
|
|
} else if (additional->npermitopen > 0) {
|
|
if (dup_strings(&ret->permitopen, &ret->npermitopen,
|
|
additional->permitopen, additional->npermitopen) != 0)
|
|
goto alloc_fail;
|
|
}
|
|
|
|
if (primary->npermitlisten > 0) {
|
|
if (dup_strings(&ret->permitlisten, &ret->npermitlisten,
|
|
primary->permitlisten, primary->npermitlisten) != 0)
|
|
goto alloc_fail;
|
|
} else if (additional->npermitlisten > 0) {
|
|
if (dup_strings(&ret->permitlisten, &ret->npermitlisten,
|
|
additional->permitlisten, additional->npermitlisten) != 0)
|
|
goto alloc_fail;
|
|
}
|
|
|
|
#define OPTFLAG_AND(x) ret->x = (primary->x == 1) && (additional->x == 1)
|
|
#define OPTFLAG_OR(x) ret->x = (primary->x == 1) || (additional->x == 1)
|
|
/* Permissive flags are logical-AND (i.e. must be set in both) */
|
|
OPTFLAG_AND(permit_port_forwarding_flag);
|
|
OPTFLAG_AND(permit_agent_forwarding_flag);
|
|
OPTFLAG_AND(permit_x11_forwarding_flag);
|
|
OPTFLAG_AND(permit_pty_flag);
|
|
OPTFLAG_AND(permit_user_rc);
|
|
OPTFLAG_AND(no_require_user_presence);
|
|
/* Restrictive flags are logical-OR (i.e. must be set in either) */
|
|
OPTFLAG_OR(require_verify);
|
|
#undef OPTFLAG_AND
|
|
|
|
/* Earliest expiry time should win */
|
|
if (primary->valid_before != 0)
|
|
ret->valid_before = primary->valid_before;
|
|
if (additional->valid_before != 0 &&
|
|
additional->valid_before < ret->valid_before)
|
|
ret->valid_before = additional->valid_before;
|
|
|
|
/*
|
|
* When both multiple forced-command are specified, only
|
|
* proceed if they are identical, otherwise fail.
|
|
*/
|
|
if (primary->force_command != NULL &&
|
|
additional->force_command != NULL) {
|
|
if (strcmp(primary->force_command,
|
|
additional->force_command) == 0) {
|
|
/* ok */
|
|
ret->force_command = strdup(primary->force_command);
|
|
if (ret->force_command == NULL)
|
|
goto alloc_fail;
|
|
} else {
|
|
errstr = "forced command options do not match";
|
|
goto fail;
|
|
}
|
|
} else if (primary->force_command != NULL) {
|
|
if ((ret->force_command = strdup(
|
|
primary->force_command)) == NULL)
|
|
goto alloc_fail;
|
|
} else if (additional->force_command != NULL) {
|
|
if ((ret->force_command = strdup(
|
|
additional->force_command)) == NULL)
|
|
goto alloc_fail;
|
|
}
|
|
/* success */
|
|
if (errstrp != NULL)
|
|
*errstrp = NULL;
|
|
return ret;
|
|
|
|
alloc_fail:
|
|
errstr = "memory allocation failed";
|
|
fail:
|
|
if (errstrp != NULL)
|
|
*errstrp = errstr;
|
|
sshauthopt_free(ret);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Copy options
|
|
*/
|
|
struct sshauthopt *
|
|
sshauthopt_copy(const struct sshauthopt *orig)
|
|
{
|
|
struct sshauthopt *ret;
|
|
|
|
if ((ret = sshauthopt_new()) == NULL)
|
|
return NULL;
|
|
|
|
#define OPTSCALAR(x) ret->x = orig->x
|
|
OPTSCALAR(permit_port_forwarding_flag);
|
|
OPTSCALAR(permit_agent_forwarding_flag);
|
|
OPTSCALAR(permit_x11_forwarding_flag);
|
|
OPTSCALAR(permit_pty_flag);
|
|
OPTSCALAR(permit_user_rc);
|
|
OPTSCALAR(restricted);
|
|
OPTSCALAR(cert_authority);
|
|
OPTSCALAR(force_tun_device);
|
|
OPTSCALAR(valid_before);
|
|
OPTSCALAR(no_require_user_presence);
|
|
OPTSCALAR(require_verify);
|
|
#undef OPTSCALAR
|
|
#define OPTSTRING(x) \
|
|
do { \
|
|
if (orig->x != NULL && (ret->x = strdup(orig->x)) == NULL) { \
|
|
sshauthopt_free(ret); \
|
|
return NULL; \
|
|
} \
|
|
} while (0)
|
|
OPTSTRING(cert_principals);
|
|
OPTSTRING(force_command);
|
|
OPTSTRING(required_from_host_cert);
|
|
OPTSTRING(required_from_host_keys);
|
|
#undef OPTSTRING
|
|
|
|
if (dup_strings(&ret->env, &ret->nenv, orig->env, orig->nenv) != 0 ||
|
|
dup_strings(&ret->permitopen, &ret->npermitopen,
|
|
orig->permitopen, orig->npermitopen) != 0 ||
|
|
dup_strings(&ret->permitlisten, &ret->npermitlisten,
|
|
orig->permitlisten, orig->npermitlisten) != 0) {
|
|
sshauthopt_free(ret);
|
|
return NULL;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
serialise_array(struct sshbuf *m, char **a, size_t n)
|
|
{
|
|
struct sshbuf *b;
|
|
size_t i;
|
|
int r = SSH_ERR_INTERNAL_ERROR;
|
|
|
|
if (n > INT_MAX)
|
|
return SSH_ERR_INTERNAL_ERROR;
|
|
|
|
if ((b = sshbuf_new()) == NULL) {
|
|
return SSH_ERR_ALLOC_FAIL;
|
|
}
|
|
for (i = 0; i < n; i++) {
|
|
if ((r = sshbuf_put_cstring(b, a[i])) != 0)
|
|
goto out;
|
|
}
|
|
if ((r = sshbuf_put_u32(m, n)) != 0 ||
|
|
(r = sshbuf_put_stringb(m, b)) != 0)
|
|
goto out;
|
|
/* success */
|
|
r = 0;
|
|
out:
|
|
sshbuf_free(b);
|
|
return r;
|
|
}
|
|
|
|
static int
|
|
deserialise_array(struct sshbuf *m, char ***ap, size_t *np)
|
|
{
|
|
char **a = NULL;
|
|
size_t i, n = 0;
|
|
struct sshbuf *b = NULL;
|
|
u_int tmp;
|
|
int r = SSH_ERR_INTERNAL_ERROR;
|
|
|
|
if ((r = sshbuf_get_u32(m, &tmp)) != 0 ||
|
|
(r = sshbuf_froms(m, &b)) != 0)
|
|
goto out;
|
|
if (tmp > INT_MAX) {
|
|
r = SSH_ERR_INVALID_FORMAT;
|
|
goto out;
|
|
}
|
|
n = tmp;
|
|
if (n > 0 && (a = calloc(n, sizeof(*a))) == NULL) {
|
|
r = SSH_ERR_ALLOC_FAIL;
|
|
goto out;
|
|
}
|
|
for (i = 0; i < n; i++) {
|
|
if ((r = sshbuf_get_cstring(b, &a[i], NULL)) != 0)
|
|
goto out;
|
|
}
|
|
/* success */
|
|
r = 0;
|
|
*ap = a;
|
|
a = NULL;
|
|
*np = n;
|
|
n = 0;
|
|
out:
|
|
if (a != NULL) {
|
|
for (i = 0; i < n; i++)
|
|
free(a[i]);
|
|
free(a);
|
|
}
|
|
sshbuf_free(b);
|
|
return r;
|
|
}
|
|
|
|
static int
|
|
serialise_nullable_string(struct sshbuf *m, const char *s)
|
|
{
|
|
int r;
|
|
|
|
if ((r = sshbuf_put_u8(m, s == NULL)) != 0 ||
|
|
(r = sshbuf_put_cstring(m, s)) != 0)
|
|
return r;
|
|
return 0;
|
|
}
|
|
|
|
static int
|
|
deserialise_nullable_string(struct sshbuf *m, char **sp)
|
|
{
|
|
int r;
|
|
u_char flag;
|
|
|
|
*sp = NULL;
|
|
if ((r = sshbuf_get_u8(m, &flag)) != 0 ||
|
|
(r = sshbuf_get_cstring(m, flag ? NULL : sp, NULL)) != 0)
|
|
return r;
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
sshauthopt_serialise(const struct sshauthopt *opts, struct sshbuf *m,
|
|
int untrusted)
|
|
{
|
|
int r = SSH_ERR_INTERNAL_ERROR;
|
|
|
|
/* Flag options */
|
|
if ((r = sshbuf_put_u8(m, opts->permit_port_forwarding_flag)) != 0 ||
|
|
(r = sshbuf_put_u8(m, opts->permit_agent_forwarding_flag)) != 0 ||
|
|
(r = sshbuf_put_u8(m, opts->permit_x11_forwarding_flag)) != 0 ||
|
|
(r = sshbuf_put_u8(m, opts->permit_pty_flag)) != 0 ||
|
|
(r = sshbuf_put_u8(m, opts->permit_user_rc)) != 0 ||
|
|
(r = sshbuf_put_u8(m, opts->restricted)) != 0 ||
|
|
(r = sshbuf_put_u8(m, opts->cert_authority)) != 0 ||
|
|
(r = sshbuf_put_u8(m, opts->no_require_user_presence)) != 0 ||
|
|
(r = sshbuf_put_u8(m, opts->require_verify)) != 0)
|
|
return r;
|
|
|
|
/* Simple integer options */
|
|
if ((r = sshbuf_put_u64(m, opts->valid_before)) != 0)
|
|
return r;
|
|
|
|
/* tunnel number can be negative to indicate "unset" */
|
|
if ((r = sshbuf_put_u8(m, opts->force_tun_device == -1)) != 0 ||
|
|
(r = sshbuf_put_u32(m, (opts->force_tun_device < 0) ?
|
|
0 : (u_int)opts->force_tun_device)) != 0)
|
|
return r;
|
|
|
|
/* String options; these may be NULL */
|
|
if ((r = serialise_nullable_string(m,
|
|
untrusted ? "yes" : opts->cert_principals)) != 0 ||
|
|
(r = serialise_nullable_string(m,
|
|
untrusted ? "true" : opts->force_command)) != 0 ||
|
|
(r = serialise_nullable_string(m,
|
|
untrusted ? NULL : opts->required_from_host_cert)) != 0 ||
|
|
(r = serialise_nullable_string(m,
|
|
untrusted ? NULL : opts->required_from_host_keys)) != 0)
|
|
return r;
|
|
|
|
/* Array options */
|
|
if ((r = serialise_array(m, opts->env,
|
|
untrusted ? 0 : opts->nenv)) != 0 ||
|
|
(r = serialise_array(m, opts->permitopen,
|
|
untrusted ? 0 : opts->npermitopen)) != 0 ||
|
|
(r = serialise_array(m, opts->permitlisten,
|
|
untrusted ? 0 : opts->npermitlisten)) != 0)
|
|
return r;
|
|
|
|
/* success */
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
sshauthopt_deserialise(struct sshbuf *m, struct sshauthopt **optsp)
|
|
{
|
|
struct sshauthopt *opts = NULL;
|
|
int r = SSH_ERR_INTERNAL_ERROR;
|
|
u_char f;
|
|
u_int tmp;
|
|
|
|
if ((opts = calloc(1, sizeof(*opts))) == NULL)
|
|
return SSH_ERR_ALLOC_FAIL;
|
|
|
|
/* Flag options */
|
|
#define OPT_FLAG(x) \
|
|
do { \
|
|
if ((r = sshbuf_get_u8(m, &f)) != 0) \
|
|
goto out; \
|
|
opts->x = f; \
|
|
} while (0)
|
|
OPT_FLAG(permit_port_forwarding_flag);
|
|
OPT_FLAG(permit_agent_forwarding_flag);
|
|
OPT_FLAG(permit_x11_forwarding_flag);
|
|
OPT_FLAG(permit_pty_flag);
|
|
OPT_FLAG(permit_user_rc);
|
|
OPT_FLAG(restricted);
|
|
OPT_FLAG(cert_authority);
|
|
OPT_FLAG(no_require_user_presence);
|
|
OPT_FLAG(require_verify);
|
|
#undef OPT_FLAG
|
|
|
|
/* Simple integer options */
|
|
if ((r = sshbuf_get_u64(m, &opts->valid_before)) != 0)
|
|
goto out;
|
|
|
|
/* tunnel number can be negative to indicate "unset" */
|
|
if ((r = sshbuf_get_u8(m, &f)) != 0 ||
|
|
(r = sshbuf_get_u32(m, &tmp)) != 0)
|
|
goto out;
|
|
opts->force_tun_device = f ? -1 : (int)tmp;
|
|
|
|
/* String options may be NULL */
|
|
if ((r = deserialise_nullable_string(m, &opts->cert_principals)) != 0 ||
|
|
(r = deserialise_nullable_string(m, &opts->force_command)) != 0 ||
|
|
(r = deserialise_nullable_string(m,
|
|
&opts->required_from_host_cert)) != 0 ||
|
|
(r = deserialise_nullable_string(m,
|
|
&opts->required_from_host_keys)) != 0)
|
|
goto out;
|
|
|
|
/* Array options */
|
|
if ((r = deserialise_array(m, &opts->env, &opts->nenv)) != 0 ||
|
|
(r = deserialise_array(m,
|
|
&opts->permitopen, &opts->npermitopen)) != 0 ||
|
|
(r = deserialise_array(m,
|
|
&opts->permitlisten, &opts->npermitlisten)) != 0)
|
|
goto out;
|
|
|
|
/* success */
|
|
r = 0;
|
|
*optsp = opts;
|
|
opts = NULL;
|
|
out:
|
|
sshauthopt_free(opts);
|
|
return r;
|
|
}
|