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readconf.c
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/* $OpenBSD: readconf.c,v 1.270 2017/03/10 04:27:32 djm Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
* Functions for reading the configuration files.
*
* As far as I am concerned, the code I have written for this software
* can be used freely for any purpose. Any derived versions of this
* software must be clearly marked as such, and if the derived work is
* incompatible with the protocol description in the RFC file, it must be
* called by a name other than "ssh" or "Secure Shell".
*/
/**************************************************************************/
/* */
/* Copyright (c) 2001, 2011 NoMachine, http://www.nomachine.com/. */
/* */
/* NXSSH, NX protocol compression and NX extensions to this software */
/* are copyright of NoMachine. Redistribution and use of the present */
/* software is allowed according to terms specified in the file LICENSE */
/* which comes in the source distribution. */
/* */
/* Check http://www.nomachine.com/licensing.html for applicability. */
/* */
/* NX and NoMachine are trademarks of Medialogic S.p.A. */
/* */
/* All rights reserved. */
/* */
/**************************************************************************/
#include "includes.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/wait.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <netdb.h>
#ifdef HAVE_PATHS_H
# include <paths.h>
#endif
#include <pwd.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#ifdef USE_SYSTEM_GLOB
# include <glob.h>
#else
# include "openbsd-compat/glob.h"
#endif
#ifdef HAVE_UTIL_H
#include <util.h>
#endif
#if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H) && !defined(BROKEN_STRNVIS)
# include <vis.h>
#endif
#include "xmalloc.h"
#include "ssh.h"
#include "compat.h"
#include "cipher.h"
#include "pathnames.h"
#include "log.h"
#include "sshkey.h"
#include "misc.h"
#include "readconf.h"
#include "match.h"
#include "kex.h"
#include "mac.h"
#include "uidswap.h"
#include "myproposal.h"
#include "digest.h"
/* Format of the configuration file:
# Configuration data is parsed as follows:
# 1. command line options
# 2. user-specific file
# 3. system-wide file
# Any configuration value is only changed the first time it is set.
# Thus, host-specific definitions should be at the beginning of the
# configuration file, and defaults at the end.
# Host-specific declarations. These may override anything above. A single
# host may match multiple declarations; these are processed in the order
# that they are given in.
Host *.ngs.fi ngs.fi
User foo
Host fake.com
HostName another.host.name.real.org
User blaah
Port 34289
ForwardX11 no
ForwardAgent no
Host books.com
RemoteForward 9999 shadows.cs.hut.fi:9999
Ciphers 3des-cbc
Host fascist.blob.com
Port 23123
User tylonen
PasswordAuthentication no
Host puukko.hut.fi
User t35124p
ProxyCommand ssh-proxy %h %p
Host *.fr
PublicKeyAuthentication no
Host *.su
Ciphers aes128-ctr
PasswordAuthentication no
Host vpn.fake.com
Tunnel yes
TunnelDevice 3
# Defaults for various options
Host *
ForwardAgent no
ForwardX11 no
PasswordAuthentication yes
RSAAuthentication yes
RhostsRSAAuthentication yes
StrictHostKeyChecking yes
TcpKeepAlive no
IdentityFile ~/.ssh/identity
Port 22
EscapeChar ~
*/
static int read_config_file_depth(const char *filename, struct passwd *pw,
const char *host, const char *original_host, Options *options,
int flags, int *activep, int depth);
static int process_config_line_depth(Options *options, struct passwd *pw,
const char *host, const char *original_host, char *line,
const char *filename, int linenum, int *activep, int flags, int depth);
/* Keyword tokens. */
typedef enum {
oBadOption,
oHost, oMatch, oInclude,
oForwardAgent, oForwardX11, oForwardX11Trusted, oForwardX11Timeout,
oGatewayPorts, oExitOnForwardFailure,
oPasswordAuthentication, oRSAAuthentication,
oChallengeResponseAuthentication, oXAuthLocation,
oIdentityFile, oHostName, oPort, oCipher, oRemoteForward, oLocalForward,
oCertificateFile, oAddKeysToAgent, oIdentityAgent,
oUser, oEscapeChar, oRhostsRSAAuthentication, oProxyCommand,
oGlobalKnownHostsFile, oUserKnownHostsFile, oConnectionAttempts,
oBatchMode, oCheckHostIP, oStrictHostKeyChecking, oHostKeyAdd, oOnlyCheck,
oCompression, oCompressionLevel, oTCPKeepAlive, oNumberOfPasswordPrompts,
oUsePrivilegedPort, oLogLevel, oCiphers, oProtocol, oMacs,
oPubkeyAuthentication,
oKbdInteractiveAuthentication, oKbdInteractiveDevices, oHostKeyAlias,
oDynamicForward, oPreferredAuthentications, oHostbasedAuthentication,
oHostKeyAlgorithms, oBindAddress, oPKCS11Provider,
oClearAllForwardings, oNoHostAuthenticationForLocalhost,
oEnableSSHKeysign, oRekeyLimit, oVerifyHostKeyDNS, oConnectTimeout,
oAddressFamily, oGssAuthentication, oGssDelegateCreds,
oServerAliveInterval, oServerAliveCountMax, oIdentitiesOnly,
oSendEnv, oControlPath, oControlMaster, oControlPersist,
oHashKnownHosts,
oTunnel, oTunnelDevice, oLocalCommand, oPermitLocalCommand,
oVisualHostKey,
oKexAlgorithms, oIPQoS, oRequestTTY, oIgnoreUnknown, oProxyUseFdpass,
oCanonicalDomains, oCanonicalizeHostname, oCanonicalizeMaxDots,
oCanonicalizeFallbackLocal, oCanonicalizePermittedCNAMEs,
oStreamLocalBindMask, oStreamLocalBindUnlink, oRevokedHostKeys,
oFingerprintHash, oUpdateHostkeys, oHostbasedKeyTypes,
oPubkeyAcceptedKeyTypes, oProxyJump,
oIgnoredUnknownOption, oDeprecated, oUnsupported
} OpCodes;
/* Textual representations of the tokens. */
static struct {
const char *name;
OpCodes opcode;
} keywords[] = {
/* Deprecated options */
{ "fallbacktorsh", oDeprecated },
{ "globalknownhostsfile2", oDeprecated },
{ "rhostsauthentication", oDeprecated },
{ "userknownhostsfile2", oDeprecated },
{ "useroaming", oDeprecated },
{ "usersh", oDeprecated },
/* Unsupported options */
{ "afstokenpassing", oUnsupported },
{ "kerberosauthentication", oUnsupported },
{ "kerberostgtpassing", oUnsupported },
/* Sometimes-unsupported options */
#if defined(GSSAPI)
{ "gssapiauthentication", oGssAuthentication },
{ "gssapidelegatecredentials", oGssDelegateCreds },
# else
{ "gssapiauthentication", oUnsupported },
{ "gssapidelegatecredentials", oUnsupported },
#endif
#ifdef ENABLE_PKCS11
{ "smartcarddevice", oPKCS11Provider },
{ "pkcs11provider", oPKCS11Provider },
# else
{ "smartcarddevice", oUnsupported },
{ "pkcs11provider", oUnsupported },
#endif
#ifdef WITH_SSH1
{ "rsaauthentication", oRSAAuthentication },
{ "rhostsrsaauthentication", oRhostsRSAAuthentication },
{ "compressionlevel", oCompressionLevel },
# else
{ "rsaauthentication", oUnsupported },
{ "rhostsrsaauthentication", oUnsupported },
{ "compressionlevel", oUnsupported },
#endif
{ "forwardagent", oForwardAgent },
{ "forwardx11", oForwardX11 },
{ "forwardx11trusted", oForwardX11Trusted },
{ "forwardx11timeout", oForwardX11Timeout },
{ "exitonforwardfailure", oExitOnForwardFailure },
{ "xauthlocation", oXAuthLocation },
{ "gatewayports", oGatewayPorts },
{ "useprivilegedport", oUsePrivilegedPort },
{ "passwordauthentication", oPasswordAuthentication },
{ "kbdinteractiveauthentication", oKbdInteractiveAuthentication },
{ "kbdinteractivedevices", oKbdInteractiveDevices },
{ "pubkeyauthentication", oPubkeyAuthentication },
{ "dsaauthentication", oPubkeyAuthentication }, /* alias */
{ "hostbasedauthentication", oHostbasedAuthentication },
{ "challengeresponseauthentication", oChallengeResponseAuthentication },
{ "skeyauthentication", oChallengeResponseAuthentication }, /* alias */
{ "tisauthentication", oChallengeResponseAuthentication }, /* alias */
{ "identityfile", oIdentityFile },
{ "identityfile2", oIdentityFile }, /* obsolete */
{ "identitiesonly", oIdentitiesOnly },
{ "certificatefile", oCertificateFile },
{ "addkeystoagent", oAddKeysToAgent },
{ "identityagent", oIdentityAgent },
{ "hostname", oHostName },
{ "hostkeyalias", oHostKeyAlias },
{ "proxycommand", oProxyCommand },
{ "port", oPort },
{ "cipher", oCipher },
{ "ciphers", oCiphers },
{ "macs", oMacs },
{ "protocol", oProtocol },
{ "remoteforward", oRemoteForward },
{ "localforward", oLocalForward },
{ "user", oUser },
{ "host", oHost },
{ "match", oMatch },
{ "escapechar", oEscapeChar },
{ "globalknownhostsfile", oGlobalKnownHostsFile },
{ "userknownhostsfile", oUserKnownHostsFile },
{ "connectionattempts", oConnectionAttempts },
{ "batchmode", oBatchMode },
{ "checkhostip", oCheckHostIP },
{ "stricthostkeychecking", oStrictHostKeyChecking },
{ "hostkeyadd", oHostKeyAdd },
{ "onlycheck", oOnlyCheck },
{ "compression", oCompression },
{ "tcpkeepalive", oTCPKeepAlive },
{ "keepalive", oTCPKeepAlive }, /* obsolete */
{ "numberofpasswordprompts", oNumberOfPasswordPrompts },
{ "loglevel", oLogLevel },
{ "dynamicforward", oDynamicForward },
{ "preferredauthentications", oPreferredAuthentications },
{ "hostkeyalgorithms", oHostKeyAlgorithms },
{ "bindaddress", oBindAddress },
{ "clearallforwardings", oClearAllForwardings },
{ "enablesshkeysign", oEnableSSHKeysign },
{ "verifyhostkeydns", oVerifyHostKeyDNS },
{ "nohostauthenticationforlocalhost", oNoHostAuthenticationForLocalhost },
{ "rekeylimit", oRekeyLimit },
{ "connecttimeout", oConnectTimeout },
{ "addressfamily", oAddressFamily },
{ "serveraliveinterval", oServerAliveInterval },
{ "serveralivecountmax", oServerAliveCountMax },
{ "sendenv", oSendEnv },
{ "controlpath", oControlPath },
{ "controlmaster", oControlMaster },
{ "controlpersist", oControlPersist },
{ "hashknownhosts", oHashKnownHosts },
{ "include", oInclude },
{ "tunnel", oTunnel },
{ "tunneldevice", oTunnelDevice },
{ "localcommand", oLocalCommand },
{ "permitlocalcommand", oPermitLocalCommand },
{ "visualhostkey", oVisualHostKey },
{ "kexalgorithms", oKexAlgorithms },
{ "ipqos", oIPQoS },
{ "requesttty", oRequestTTY },
{ "proxyusefdpass", oProxyUseFdpass },
{ "canonicaldomains", oCanonicalDomains },
{ "canonicalizefallbacklocal", oCanonicalizeFallbackLocal },
{ "canonicalizehostname", oCanonicalizeHostname },
{ "canonicalizemaxdots", oCanonicalizeMaxDots },
{ "canonicalizepermittedcnames", oCanonicalizePermittedCNAMEs },
{ "streamlocalbindmask", oStreamLocalBindMask },
{ "streamlocalbindunlink", oStreamLocalBindUnlink },
{ "revokedhostkeys", oRevokedHostKeys },
{ "fingerprinthash", oFingerprintHash },
{ "updatehostkeys", oUpdateHostkeys },
{ "hostbasedkeytypes", oHostbasedKeyTypes },
{ "pubkeyacceptedkeytypes", oPubkeyAcceptedKeyTypes },
{ "ignoreunknown", oIgnoreUnknown },
{ "proxyjump", oProxyJump },
{ NULL, oBadOption }
};
/*
* Adds a local TCP/IP port forward to options. Never returns if there is an
* error.
*/
void
add_local_forward(Options *options, const struct Forward *newfwd)
{
struct Forward *fwd;
extern uid_t original_real_uid;
int i;
if (!bind_permitted(newfwd->listen_port, original_real_uid) &&
newfwd->listen_path == NULL)
fatal("Privileged ports can only be forwarded by root.");
/* Don't add duplicates */
for (i = 0; i < options->num_local_forwards; i++) {
if (forward_equals(newfwd, options->local_forwards + i))
return;
}
options->local_forwards = xreallocarray(options->local_forwards,
options->num_local_forwards + 1,
sizeof(*options->local_forwards));
fwd = &options->local_forwards[options->num_local_forwards++];
fwd->listen_host = newfwd->listen_host;
fwd->listen_port = newfwd->listen_port;
fwd->listen_path = newfwd->listen_path;
fwd->connect_host = newfwd->connect_host;
fwd->connect_port = newfwd->connect_port;
fwd->connect_path = newfwd->connect_path;
}
/*
* Adds a remote TCP/IP port forward to options. Never returns if there is
* an error.
*/
void
add_remote_forward(Options *options, const struct Forward *newfwd)
{
struct Forward *fwd;
int i;
/* Don't add duplicates */
for (i = 0; i < options->num_remote_forwards; i++) {
if (forward_equals(newfwd, options->remote_forwards + i))
return;
}
options->remote_forwards = xreallocarray(options->remote_forwards,
options->num_remote_forwards + 1,
sizeof(*options->remote_forwards));
fwd = &options->remote_forwards[options->num_remote_forwards++];
fwd->listen_host = newfwd->listen_host;
fwd->listen_port = newfwd->listen_port;
fwd->listen_path = newfwd->listen_path;
fwd->connect_host = newfwd->connect_host;
fwd->connect_port = newfwd->connect_port;
fwd->connect_path = newfwd->connect_path;
fwd->handle = newfwd->handle;
fwd->allocated_port = 0;
}
static void
clear_forwardings(Options *options)
{
int i;
for (i = 0; i < options->num_local_forwards; i++) {
free(options->local_forwards[i].listen_host);
free(options->local_forwards[i].listen_path);
free(options->local_forwards[i].connect_host);
free(options->local_forwards[i].connect_path);
}
if (options->num_local_forwards > 0) {
free(options->local_forwards);
options->local_forwards = NULL;
}
options->num_local_forwards = 0;
for (i = 0; i < options->num_remote_forwards; i++) {
free(options->remote_forwards[i].listen_host);
free(options->remote_forwards[i].listen_path);
free(options->remote_forwards[i].connect_host);
free(options->remote_forwards[i].connect_path);
}
if (options->num_remote_forwards > 0) {
free(options->remote_forwards);
options->remote_forwards = NULL;
}
options->num_remote_forwards = 0;
options->tun_open = SSH_TUNMODE_NO;
}
void
add_certificate_file(Options *options, const char *path, int userprovided)
{
int i;
if (options->num_certificate_files >= SSH_MAX_CERTIFICATE_FILES)
fatal("Too many certificate files specified (max %d)",
SSH_MAX_CERTIFICATE_FILES);
/* Avoid registering duplicates */
for (i = 0; i < options->num_certificate_files; i++) {
if (options->certificate_file_userprovided[i] == userprovided &&
strcmp(options->certificate_files[i], path) == 0) {
debug2("%s: ignoring duplicate key %s", __func__, path);
return;
}
}
options->certificate_file_userprovided[options->num_certificate_files] =
userprovided;
options->certificate_files[options->num_certificate_files++] =
xstrdup(path);
}
void
add_identity_file(Options *options, const char *dir, const char *filename,
int userprovided)
{
char *path;
int i;
if (options->num_identity_files >= SSH_MAX_IDENTITY_FILES)
fatal("Too many identity files specified (max %d)",
SSH_MAX_IDENTITY_FILES);
if (dir == NULL) /* no dir, filename is absolute */
path = xstrdup(filename);
else
(void)xasprintf(&path, "%.100s%.100s", dir, filename);
/* Avoid registering duplicates */
for (i = 0; i < options->num_identity_files; i++) {
if (options->identity_file_userprovided[i] == userprovided &&
strcmp(options->identity_files[i], path) == 0) {
debug2("%s: ignoring duplicate key %s", __func__, path);
free(path);
return;
}
}
options->identity_file_userprovided[options->num_identity_files] =
userprovided;
options->identity_files[options->num_identity_files++] = path;
}
int
default_ssh_port(void)
{
static int port;
struct servent *sp;
if (port == 0) {
sp = getservbyname(SSH_SERVICE_NAME, "tcp");
port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
}
return port;
}
/*
* Execute a command in a shell.
* Return its exit status or -1 on abnormal exit.
*/
static int
execute_in_shell(const char *cmd)
{
char *shell;
pid_t pid;
int devnull, status;
extern uid_t original_real_uid;
if ((shell = getenv("SHELL")) == NULL)
shell = _PATH_BSHELL;
/* Need this to redirect subprocess stdin/out */
if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1)
fatal("open(/dev/null): %s", strerror(errno));
debug("Executing command: '%.500s'", cmd);
/* Fork and execute the command. */
if ((pid = fork()) == 0) {
char *argv[4];
/* Child. Permanently give up superuser privileges. */
permanently_drop_suid(original_real_uid);
/* Redirect child stdin and stdout. Leave stderr */
if (dup2(devnull, STDIN_FILENO) == -1)
fatal("dup2: %s", strerror(errno));
if (dup2(devnull, STDOUT_FILENO) == -1)
fatal("dup2: %s", strerror(errno));
if (devnull > STDERR_FILENO)
close(devnull);
closefrom(STDERR_FILENO + 1);
argv[0] = shell;
argv[1] = "-c";
argv[2] = xstrdup(cmd);
argv[3] = NULL;
execv(argv[0], argv);
error("Unable to execute '%.100s': %s", cmd, strerror(errno));
/* Die with signal to make this error apparent to parent. */
signal(SIGTERM, SIG_DFL);
kill(getpid(), SIGTERM);
_exit(1);
}
/* Parent. */
if (pid < 0)
fatal("%s: fork: %.100s", __func__, strerror(errno));
close(devnull);
while (waitpid(pid, &status, 0) == -1) {
if (errno != EINTR && errno != EAGAIN)
fatal("%s: waitpid: %s", __func__, strerror(errno));
}
if (!WIFEXITED(status)) {
error("command '%.100s' exited abnormally", cmd);
return -1;
}
debug3("command returned status %d", WEXITSTATUS(status));
return WEXITSTATUS(status);
}
/*
* Parse and execute a Match directive.
*/
static int
match_cfg_line(Options *options, char **condition, struct passwd *pw,
const char *host_arg, const char *original_host, int post_canon,
const char *filename, int linenum)
{
char *arg, *oattrib, *attrib, *cmd, *cp = *condition, *host, *criteria;
const char *ruser;
int r, port, this_result, result = 1, attributes = 0, negate;
char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
/*
* Configuration is likely to be incomplete at this point so we
* must be prepared to use default values.
*/
port = options->port <= 0 ? default_ssh_port() : options->port;
ruser = options->user == NULL ? pw->pw_name : options->user;
if (post_canon) {
host = xstrdup(options->hostname);
} else if (options->hostname != NULL) {
/* NB. Please keep in sync with ssh.c:main() */
host = percent_expand(options->hostname,
"h", host_arg, (char *)NULL);
} else {
host = xstrdup(host_arg);
}
debug2("checking match for '%s' host %s originally %s",
cp, host, original_host);
while ((oattrib = attrib = strdelim(&cp)) && *attrib != '\0') {
criteria = NULL;
this_result = 1;
if ((negate = attrib[0] == '!'))
attrib++;
/* criteria "all" and "canonical" have no argument */
if (strcasecmp(attrib, "all") == 0) {
if (attributes > 1 ||
((arg = strdelim(&cp)) != NULL && *arg != '\0')) {
error("%.200s line %d: '%s' cannot be combined "
"with other Match attributes",
filename, linenum, oattrib);
result = -1;
goto out;
}
if (result)
result = negate ? 0 : 1;
goto out;
}
attributes++;
if (strcasecmp(attrib, "canonical") == 0) {
r = !!post_canon; /* force bitmask member to boolean */
if (r == (negate ? 1 : 0))
this_result = result = 0;
debug3("%.200s line %d: %smatched '%s'",
filename, linenum,
this_result ? "" : "not ", oattrib);
continue;
}
/* All other criteria require an argument */
if ((arg = strdelim(&cp)) == NULL || *arg == '\0') {
error("Missing Match criteria for %s", attrib);
result = -1;
goto out;
}
if (strcasecmp(attrib, "host") == 0) {
criteria = xstrdup(host);
r = match_hostname(host, arg) == 1;
if (r == (negate ? 1 : 0))
this_result = result = 0;
} else if (strcasecmp(attrib, "originalhost") == 0) {
criteria = xstrdup(original_host);
r = match_hostname(original_host, arg) == 1;
if (r == (negate ? 1 : 0))
this_result = result = 0;
} else if (strcasecmp(attrib, "user") == 0) {
criteria = xstrdup(ruser);
r = match_pattern_list(ruser, arg, 0) == 1;
if (r == (negate ? 1 : 0))
this_result = result = 0;
} else if (strcasecmp(attrib, "localuser") == 0) {
criteria = xstrdup(pw->pw_name);
r = match_pattern_list(pw->pw_name, arg, 0) == 1;
if (r == (negate ? 1 : 0))
this_result = result = 0;
} else if (strcasecmp(attrib, "exec") == 0) {
if (gethostname(thishost, sizeof(thishost)) == -1)
fatal("gethostname: %s", strerror(errno));
strlcpy(shorthost, thishost, sizeof(shorthost));
shorthost[strcspn(thishost, ".")] = '\0';
snprintf(portstr, sizeof(portstr), "%d", port);
cmd = percent_expand(arg,
"L", shorthost,
"d", pw->pw_dir,
"h", host,
"l", thishost,
"n", original_host,
"p", portstr,
"r", ruser,
"u", pw->pw_name,
(char *)NULL);
if (result != 1) {
/* skip execution if prior predicate failed */
debug3("%.200s line %d: skipped exec "
"\"%.100s\"", filename, linenum, cmd);
free(cmd);
continue;
}
r = execute_in_shell(cmd);
if (r == -1) {
fatal("%.200s line %d: match exec "
"'%.100s' error", filename,
linenum, cmd);
}
criteria = xstrdup(cmd);
free(cmd);
/* Force exit status to boolean */
r = r == 0;
if (r == (negate ? 1 : 0))
this_result = result = 0;
} else {
error("Unsupported Match attribute %s", attrib);
result = -1;
goto out;
}
debug3("%.200s line %d: %smatched '%s \"%.100s\"' ",
filename, linenum, this_result ? "": "not ",
oattrib, criteria);
free(criteria);
}
if (attributes == 0) {
error("One or more attributes required for Match");
result = -1;
goto out;
}
out:
if (result != -1)
debug2("match %sfound", result ? "" : "not ");
*condition = cp;
free(host);
return result;
}
/* Check and prepare a domain name: removes trailing '.' and lowercases */
static void
valid_domain(char *name, const char *filename, int linenum)
{
size_t i, l = strlen(name);
u_char c, last = '\0';
if (l == 0)
fatal("%s line %d: empty hostname suffix", filename, linenum);
if (!isalpha((u_char)name[0]) && !isdigit((u_char)name[0]))
fatal("%s line %d: hostname suffix \"%.100s\" "
"starts with invalid character", filename, linenum, name);
for (i = 0; i < l; i++) {
c = tolower((u_char)name[i]);
name[i] = (char)c;
if (last == '.' && c == '.')
fatal("%s line %d: hostname suffix \"%.100s\" contains "
"consecutive separators", filename, linenum, name);
if (c != '.' && c != '-' && !isalnum(c) &&
c != '_') /* technically invalid, but common */
fatal("%s line %d: hostname suffix \"%.100s\" contains "
"invalid characters", filename, linenum, name);
last = c;
}
if (name[l - 1] == '.')
name[l - 1] = '\0';
}
/*
* Returns the number of the token pointed to by cp or oBadOption.
*/
static OpCodes
parse_token(const char *cp, const char *filename, int linenum,
const char *ignored_unknown)
{
int i;
for (i = 0; keywords[i].name; i++)
if (strcmp(cp, keywords[i].name) == 0)
return keywords[i].opcode;
if (ignored_unknown != NULL &&
match_pattern_list(cp, ignored_unknown, 1) == 1)
return oIgnoredUnknownOption;
error("%s: line %d: Bad configuration option: %s",
filename, linenum, cp);
return oBadOption;
}
/* Multistate option parsing */
struct multistate {
char *key;
int value;
};
static const struct multistate multistate_flag[] = {
{ "true", 1 },
{ "false", 0 },
{ "yes", 1 },
{ "no", 0 },
{ NULL, -1 }
};
static const struct multistate multistate_yesnoask[] = {
{ "true", 1 },
{ "false", 0 },
{ "yes", 1 },
{ "no", 0 },
{ "ask", 2 },
{ NULL, -1 }
};
static const struct multistate multistate_yesnoaskconfirm[] = {
{ "true", 1 },
{ "false", 0 },
{ "yes", 1 },
{ "no", 0 },
{ "ask", 2 },
{ "confirm", 3 },
{ NULL, -1 }
};
static const struct multistate multistate_addressfamily[] = {
{ "inet", AF_INET },
{ "inet6", AF_INET6 },
{ "any", AF_UNSPEC },
{ NULL, -1 }
};
static const struct multistate multistate_controlmaster[] = {
{ "true", SSHCTL_MASTER_YES },
{ "yes", SSHCTL_MASTER_YES },
{ "false", SSHCTL_MASTER_NO },
{ "no", SSHCTL_MASTER_NO },
{ "auto", SSHCTL_MASTER_AUTO },
{ "ask", SSHCTL_MASTER_ASK },
{ "autoask", SSHCTL_MASTER_AUTO_ASK },
{ NULL, -1 }
};
static const struct multistate multistate_tunnel[] = {
{ "ethernet", SSH_TUNMODE_ETHERNET },
{ "point-to-point", SSH_TUNMODE_POINTOPOINT },
{ "true", SSH_TUNMODE_DEFAULT },
{ "yes", SSH_TUNMODE_DEFAULT },
{ "false", SSH_TUNMODE_NO },
{ "no", SSH_TUNMODE_NO },
{ NULL, -1 }
};
static const struct multistate multistate_requesttty[] = {
{ "true", REQUEST_TTY_YES },
{ "yes", REQUEST_TTY_YES },
{ "false", REQUEST_TTY_NO },
{ "no", REQUEST_TTY_NO },
{ "force", REQUEST_TTY_FORCE },
{ "auto", REQUEST_TTY_AUTO },
{ NULL, -1 }
};
static const struct multistate multistate_canonicalizehostname[] = {
{ "true", SSH_CANONICALISE_YES },
{ "false", SSH_CANONICALISE_NO },
{ "yes", SSH_CANONICALISE_YES },
{ "no", SSH_CANONICALISE_NO },
{ "always", SSH_CANONICALISE_ALWAYS },
{ NULL, -1 }
};
/*
* Processes a single option line as used in the configuration files. This
* only sets those values that have not already been set.
*/
int
process_config_line(Options *options, struct passwd *pw, const char *host,
const char *original_host, char *line, const char *filename,
int linenum, int *activep, int flags)
{
return process_config_line_depth(options, pw, host, original_host,
line, filename, linenum, activep, flags, 0);
}
#define WHITESPACE " \t\r\n"
static int
process_config_line_depth(Options *options, struct passwd *pw, const char *host,
const char *original_host, char *line, const char *filename,
int linenum, int *activep, int flags, int depth)
{
char *s, **charptr, *endofnumber, *keyword, *arg, *arg2;
char **cpptr, fwdarg[256];
u_int i, *uintptr, max_entries = 0;
int r, oactive, negated, opcode, *intptr, value, value2, cmdline = 0;
LogLevel *log_level_ptr;
long long val64;
size_t len;
struct Forward fwd;
const struct multistate *multistate_ptr;
struct allowed_cname *cname;
glob_t gl;
if (activep == NULL) { /* We are processing a command line directive */
cmdline = 1;
activep = &cmdline;
}
/* Strip trailing whitespace. Allow \f (form feed) at EOL only */
if ((len = strlen(line)) == 0)
return 0;
for (len--; len > 0; len--) {
if (strchr(WHITESPACE "\f", line[len]) == NULL)
break;
line[len] = '\0';
}
s = line;
/* Get the keyword. (Each line is supposed to begin with a keyword). */
if ((keyword = strdelim(&s)) == NULL)
return 0;
/* Ignore leading whitespace. */
if (*keyword == '\0')
keyword = strdelim(&s);
if (keyword == NULL || !*keyword || *keyword == '\n' || *keyword == '#')
return 0;
/* Match lowercase keyword */
lowercase(keyword);
opcode = parse_token(keyword, filename, linenum,
options->ignored_unknown);
switch (opcode) {
case oBadOption:
/* don't panic, but count bad options */
return -1;
case oIgnoredUnknownOption:
debug("%s line %d: Ignored unknown option \"%s\"",
filename, linenum, keyword);
return 0;
case oConnectTimeout:
intptr = &options->connection_timeout;
parse_time:
arg = strdelim(&s);
if (!arg || *arg == '\0')
fatal("%s line %d: missing time value.",
filename, linenum);
if (strcmp(arg, "none") == 0)
value = -1;
else if ((value = convtime(arg)) == -1)
fatal("%s line %d: invalid time value.",
filename, linenum);
if (*activep && *intptr == -1)
*intptr = value;
break;
case oForwardAgent:
intptr = &options->forward_agent;
parse_flag:
multistate_ptr = multistate_flag;
parse_multistate:
arg = strdelim(&s);
if (!arg || *arg == '\0')
fatal("%s line %d: missing argument.",
filename, linenum);
value = -1;
for (i = 0; multistate_ptr[i].key != NULL; i++) {
if (strcasecmp(arg, multistate_ptr[i].key) == 0) {
value = multistate_ptr[i].value;
break;
}
}
if (value == -1)
fatal("%s line %d: unsupported option \"%s\".",
filename, linenum, arg);
if (*activep && *intptr == -1)
*intptr = value;
break;
case oForwardX11:
intptr = &options->forward_x11;
goto parse_flag;
case oForwardX11Trusted:
intptr = &options->forward_x11_trusted;
goto parse_flag;
case oForwardX11Timeout:
intptr = &options->forward_x11_timeout;
goto parse_time;
case oGatewayPorts:
intptr = &options->fwd_opts.gateway_ports;
goto parse_flag;
case oExitOnForwardFailure:
intptr = &options->exit_on_forward_failure;
goto parse_flag;
case oUsePrivilegedPort:
intptr = &options->use_privileged_port;
goto parse_flag;
case oPasswordAuthentication:
intptr = &options->password_authentication;
goto parse_flag;
case oKbdInteractiveAuthentication:
intptr = &options->kbd_interactive_authentication;
goto parse_flag;
case oKbdInteractiveDevices:
charptr = &options->kbd_interactive_devices;
goto parse_string;
case oPubkeyAuthentication:
intptr = &options->pubkey_authentication;
goto parse_flag;
case oRSAAuthentication:
intptr = &options->rsa_authentication;
goto parse_flag;
case oRhostsRSAAuthentication:
intptr = &options->rhosts_rsa_authentication;
goto parse_flag;
case oHostbasedAuthentication:
intptr = &options->hostbased_authentication;
goto parse_flag;
case oChallengeResponseAuthentication:
intptr = &options->challenge_response_authentication;
goto parse_flag;
case oGssAuthentication:
intptr = &options->gss_authentication;
goto parse_flag;
case oGssDelegateCreds:
intptr = &options->gss_deleg_creds;
goto parse_flag;
case oBatchMode:
intptr = &options->batch_mode;