/* $OpenBSD: readconf.c,v 1.239 2015/07/30 00:01:34 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". */ #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 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 Cipher 3des 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 Cipher none 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 ~ */ /* Keyword tokens. */ typedef enum { oBadOption, oHost, oMatch, oForwardAgent, oForwardX11, oForwardX11Trusted, oForwardX11Timeout, oGatewayPorts, oExitOnForwardFailure, oPasswordAuthentication, oRSAAuthentication, oChallengeResponseAuthentication, oXAuthLocation, oIdentityFile, oHostName, oPort, oCipher, oRemoteForward, oLocalForward, oUser, oEscapeChar, oRhostsRSAAuthentication, oProxyCommand, oGlobalKnownHostsFile, oUserKnownHostsFile, oConnectionAttempts, oBatchMode, oCheckHostIP, oStrictHostKeyChecking, 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, oUseRoaming, oKexAlgorithms, oIPQoS, oRequestTTY, oIgnoreUnknown, oProxyUseFdpass, oCanonicalDomains, oCanonicalizeHostname, oCanonicalizeMaxDots, oCanonicalizeFallbackLocal, oCanonicalizePermittedCNAMEs, oStreamLocalBindMask, oStreamLocalBindUnlink, oRevokedHostKeys, oFingerprintHash, oUpdateHostkeys, oHostbasedKeyTypes, oPubkeyAcceptedKeyTypes, oIgnoredUnknownOption, oDeprecated, oUnsupported } OpCodes; /* Textual representations of the tokens. */ static struct { const char *name; OpCodes opcode; } keywords[] = { { "forwardagent", oForwardAgent }, { "forwardx11", oForwardX11 }, { "forwardx11trusted", oForwardX11Trusted }, { "forwardx11timeout", oForwardX11Timeout }, { "exitonforwardfailure", oExitOnForwardFailure }, { "xauthlocation", oXAuthLocation }, { "gatewayports", oGatewayPorts }, { "useprivilegedport", oUsePrivilegedPort }, { "rhostsauthentication", oDeprecated }, { "passwordauthentication", oPasswordAuthentication }, { "kbdinteractiveauthentication", oKbdInteractiveAuthentication }, { "kbdinteractivedevices", oKbdInteractiveDevices }, { "rsaauthentication", oRSAAuthentication }, { "pubkeyauthentication", oPubkeyAuthentication }, { "dsaauthentication", oPubkeyAuthentication }, /* alias */ { "rhostsrsaauthentication", oRhostsRSAAuthentication }, { "hostbasedauthentication", oHostbasedAuthentication }, { "challengeresponseauthentication", oChallengeResponseAuthentication }, { "skeyauthentication", oChallengeResponseAuthentication }, /* alias */ { "tisauthentication", oChallengeResponseAuthentication }, /* alias */ { "kerberosauthentication", oUnsupported }, { "kerberostgtpassing", oUnsupported }, { "afstokenpassing", oUnsupported }, #if defined(GSSAPI) { "gssapiauthentication", oGssAuthentication }, { "gssapidelegatecredentials", oGssDelegateCreds }, #else { "gssapiauthentication", oUnsupported }, { "gssapidelegatecredentials", oUnsupported }, #endif { "fallbacktorsh", oDeprecated }, { "usersh", oDeprecated }, { "identityfile", oIdentityFile }, { "identityfile2", oIdentityFile }, /* obsolete */ { "identitiesonly", oIdentitiesOnly }, { "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 }, { "globalknownhostsfile2", oDeprecated }, { "userknownhostsfile", oUserKnownHostsFile }, { "userknownhostsfile2", oDeprecated }, { "connectionattempts", oConnectionAttempts }, { "batchmode", oBatchMode }, { "checkhostip", oCheckHostIP }, { "stricthostkeychecking", oStrictHostKeyChecking }, { "compression", oCompression }, { "compressionlevel", oCompressionLevel }, { "tcpkeepalive", oTCPKeepAlive }, { "keepalive", oTCPKeepAlive }, /* obsolete */ { "numberofpasswordprompts", oNumberOfPasswordPrompts }, { "loglevel", oLogLevel }, { "dynamicforward", oDynamicForward }, { "preferredauthentications", oPreferredAuthentications }, { "hostkeyalgorithms", oHostKeyAlgorithms }, { "bindaddress", oBindAddress }, #ifdef ENABLE_PKCS11 { "smartcarddevice", oPKCS11Provider }, { "pkcs11provider", oPKCS11Provider }, #else { "smartcarddevice", oUnsupported }, { "pkcs11provider", oUnsupported }, #endif { "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 }, { "tunnel", oTunnel }, { "tunneldevice", oTunnelDevice }, { "localcommand", oLocalCommand }, { "permitlocalcommand", oPermitLocalCommand }, { "visualhostkey", oVisualHostKey }, { "useroaming", oUseRoaming }, { "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 }, { 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; #ifndef NO_IPPORT_RESERVED_CONCEPT extern uid_t original_real_uid; if (newfwd->listen_port < IPPORT_RESERVED && original_real_uid != 0 && newfwd->listen_path == NULL) fatal("Privileged ports can only be forwarded by root."); #endif 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; 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_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, *command_string; pid_t pid; int devnull, status; extern uid_t original_real_uid; if ((shell = getenv("SHELL")) == NULL) shell = _PATH_BSHELL; /* * Use "exec" to avoid "sh -c" processes on some platforms * (e.g. Solaris) */ xasprintf(&command_string, "exec %s", cmd); /* 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] = command_string; 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); free(command_string); 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 (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_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. */ #define WHITESPACE " \t\r\n" 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) { char *s, **charptr, *endofnumber, *keyword, *arg, *arg2; char **cpptr, fwdarg[256]; u_int i, *uintptr, max_entries = 0; int 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; if (activep == NULL) { /* We are processing a command line directive */ cmdline = 1; activep = &cmdline; } /* Strip trailing whitespace */ if ((len = strlen(line)) == 0) return 0; for (len--; len > 0; len--) { if (strchr(WHITESPACE, 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; /* NOTREACHED */ 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; goto parse_flag; case oCheckHostIP: intptr = &options->check_host_ip; goto parse_flag; case oVerifyHostKeyDNS: intptr = &options->verify_host_key_dns; multistate_ptr = multistate_yesnoask; goto parse_multistate; case oStrictHostKeyChecking: intptr = &options->strict_host_key_checking; multistate_ptr = multistate_yesnoask; goto parse_multistate; case oCompression: intptr = &options->compression; goto parse_flag; case oTCPKeepAlive: intptr = &options->tcp_keep_alive; goto parse_flag; case oNoHostAuthenticationForLocalhost: intptr = &options->no_host_authentication_for_localhost; goto parse_flag; case oNumberOfPasswordPrompts: intptr = &options->number_of_password_prompts; goto parse_int; case oCompressionLevel: intptr = &options->compression_level; goto parse_int; case oRekeyLimit: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (strcmp(arg, "default") == 0) { val64 = 0; } else { if (scan_scaled(arg, &val64) == -1) fatal("%.200s line %d: Bad number '%s': %s", filename, linenum, arg, strerror(errno)); /* check for too-large or too-small limits */ if (val64 > UINT_MAX) fatal("%.200s line %d: RekeyLimit too large", filename, linenum); if (val64 != 0 && val64 < 16) fatal("%.200s line %d: RekeyLimit too small", filename, linenum); } if (*activep && options->rekey_limit == -1) options->rekey_limit = (u_int32_t)val64; if (s != NULL) { /* optional rekey interval present */ if (strcmp(s, "none") == 0) { (void)strdelim(&s); /* discard */ break; } intptr = &options->rekey_interval; goto parse_time; } break; case oIdentityFile: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (*activep) { intptr = &options->num_identity_files; if (*intptr >= SSH_MAX_IDENTITY_FILES) fatal("%.200s line %d: Too many identity files specified (max %d).", filename, linenum, SSH_MAX_IDENTITY_FILES); add_identity_file(options, NULL, arg, flags & SSHCONF_USERCONF); } break; case oXAuthLocation: charptr=&options->xauth_location; goto parse_string; case oUser: charptr = &options->user; parse_string: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (*activep && *charptr == NULL) *charptr = xstrdup(arg); break; case oGlobalKnownHostsFile: cpptr = (char **)&options->system_hostfiles; uintptr = &options->num_system_hostfiles; max_entries = SSH_MAX_HOSTS_FILES; parse_char_array: if (*activep && *uintptr == 0) { while ((arg = strdelim(&s)) != NULL && *arg != '\0') { if ((*uintptr) >= max_entries) fatal("%s line %d: " "too many authorized keys files.", filename, linenum); cpptr[(*uintptr)++] = xstrdup(arg); } } return 0; case oUserKnownHostsFile: cpptr = (char **)&options->user_hostfiles; uintptr = &options->num_user_hostfiles; max_entries = SSH_MAX_HOSTS_FILES; goto parse_char_array; case oHostName: charptr = &options->hostname; goto parse_string; case oHostKeyAlias: charptr = &options->host_key_alias; goto parse_string; case oPreferredAuthentications: charptr = &options->preferred_authentications; goto parse_string; case oBindAddress: charptr = &options->bind_address; goto parse_string; case oPKCS11Provider: charptr = &options->pkcs11_provider; goto parse_string; case oProxyCommand: charptr = &options->proxy_command; parse_command: if (s == NULL) fatal("%.200s line %d: Missing argument.", filename, linenum); len = strspn(s, WHITESPACE "="); if (*activep && *charptr == NULL) *charptr = xstrdup(s + len); return 0; case oPort: intptr = &options->port; parse_int: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (arg[0] < '0' || arg[0] > '9') fatal("%.200s line %d: Bad number.", filename, linenum); /* Octal, decimal, or hex format? */ value = strtol(arg, &endofnumber, 0); if (arg == endofnumber) fatal("%.200s line %d: Bad number.", filename, linenum); if (*activep && *intptr == -1) *intptr = value; break; case oConnectionAttempts: intptr = &options->connection_attempts; goto parse_int; case oCipher: intptr = &options->cipher; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); value = cipher_number(arg); if (value == -1) fatal("%.200s line %d: Bad cipher '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && *intptr == -1) *intptr = value; break; case oCiphers: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!ciphers_valid(*arg == '+' ? arg + 1 : arg)) fatal("%.200s line %d: Bad SSH2 cipher spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && options->ciphers == NULL) options->ciphers = xstrdup(arg); break; case oMacs: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!mac_valid(*arg == '+' ? arg + 1 : arg)) fatal("%.200s line %d: Bad SSH2 Mac spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && options->macs == NULL) options->macs = xstrdup(arg); break; case oKexAlgorithms: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!kex_names_valid(*arg == '+' ? arg + 1 : arg)) fatal("%.200s line %d: Bad SSH2 KexAlgorithms '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && options->kex_algorithms == NULL) options->kex_algorithms = xstrdup(arg); break; case oHostKeyAlgorithms: charptr = &options->hostkeyalgorithms; parse_keytypes: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (!sshkey_names_valid2(*arg == '+' ? arg + 1 : arg, 1)) fatal("%s line %d: Bad key types '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && *charptr == NULL) *charptr = xstrdup(arg); break; case oProtocol: intptr = &options->protocol; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); value = proto_spec(arg); if (value == SSH_PROTO_UNKNOWN) fatal("%.200s line %d: Bad protocol spec '%s'.", filename, linenum, arg ? arg : "<NONE>"); if (*activep && *intptr == SSH_PROTO_UNKNOWN) *intptr = value; break; case oLogLevel: log_level_ptr = &options->log_level; arg = strdelim(&s); value = log_level_number(arg); if (value == SYSLOG_LEVEL_NOT_SET) fatal("%.200s line %d: unsupported log level '%s'", filename, linenum, arg ? arg : "<NONE>"); if (*activep && *log_level_ptr == SYSLOG_LEVEL_NOT_SET) *log_level_ptr = (LogLevel) value; break; case oLocalForward: case oRemoteForward: case oDynamicForward: arg = strdelim(&s); if (arg == NULL || *arg == '\0') fatal("%.200s line %d: Missing port argument.", filename, linenum); if (opcode == oLocalForward || opcode == oRemoteForward) { arg2 = strdelim(&s); if (arg2 == NULL || *arg2 == '\0') fatal("%.200s line %d: Missing target argument.", filename, linenum); /* construct a string for parse_forward */ snprintf(fwdarg, sizeof(fwdarg), "%s:%s", arg, arg2); } else if (opcode == oDynamicForward) { strlcpy(fwdarg, arg, sizeof(fwdarg)); } if (parse_forward(&fwd, fwdarg, opcode == oDynamicForward ? 1 : 0, opcode == oRemoteForward ? 1 : 0) == 0) fatal("%.200s line %d: Bad forwarding specification.", filename, linenum); if (*activep) { if (opcode == oLocalForward || opcode == oDynamicForward) add_local_forward(options, &fwd); else if (opcode == oRemoteForward) add_remote_forward(options, &fwd); } break; case oClearAllForwardings: intptr = &options->clear_forwardings; goto parse_flag; case oHost: if (cmdline) fatal("Host directive not supported as a command-line " "option"); *activep = 0; arg2 = NULL; while ((arg = strdelim(&s)) != NULL && *arg != '\0') { negated = *arg == '!'; if (negated) arg++; if (match_pattern(host, arg)) { if (negated) { debug("%.200s line %d: Skipping Host " "block because of negated match " "for %.100s", filename, linenum, arg); *activep = 0; break; } if (!*activep) arg2 = arg; /* logged below */ *activep = 1; } } if (*activep) debug("%.200s line %d: Applying options for %.100s", filename, linenum, arg2); /* Avoid garbage check below, as strdelim is done. */ return 0; case oMatch: if (cmdline) fatal("Host directive not supported as a command-line " "option"); value = match_cfg_line(options, &s, pw, host, original_host, flags & SSHCONF_POSTCANON, filename, linenum); if (value < 0) fatal("%.200s line %d: Bad Match condition", filename, linenum); *activep = value; break; case oEscapeChar: intptr = &options->escape_char; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if (strcmp(arg, "none") == 0) value = SSH_ESCAPECHAR_NONE; else if (arg[1] == '\0') value = (u_char) arg[0]; else if (arg[0] == '^' && arg[2] == 0 && (u_char) arg[1] >= 64 && (u_char) arg[1] < 128) value = (u_char) arg[1] & 31; else { fatal("%.200s line %d: Bad escape character.", filename, linenum); /* NOTREACHED */ value = 0; /* Avoid compiler warning. */ } if (*activep && *intptr == -1) *intptr = value; break; case oAddressFamily: intptr = &options->address_family; multistate_ptr = multistate_addressfamily; goto parse_multistate; case oEnableSSHKeysign: intptr = &options->enable_ssh_keysign; goto parse_flag; case oIdentitiesOnly: intptr = &options->identities_only; goto parse_flag; case oServerAliveInterval: intptr = &options->server_alive_interval; goto parse_time; case oServerAliveCountMax: intptr = &options->server_alive_count_max; goto parse_int; case oSendEnv: while ((arg = strdelim(&s)) != NULL && *arg != '\0') { if (strchr(arg, '=') != NULL) fatal("%s line %d: Invalid environment name.", filename, linenum); if (!*activep) continue; if (options->num_send_env >= MAX_SEND_ENV) fatal("%s line %d: too many send env.", filename, linenum); options->send_env[options->num_send_env++] = xstrdup(arg); } break; case oControlPath: charptr = &options->control_path; goto parse_string; case oControlMaster: intptr = &options->control_master; multistate_ptr = multistate_controlmaster; goto parse_multistate; case oControlPersist: /* no/false/yes/true, or a time spec */ intptr = &options->control_persist; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing ControlPersist" " argument.", filename, linenum); value = 0; value2 = 0; /* timeout */ if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0) value = 0; else if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0) value = 1; else if ((value2 = convtime(arg)) >= 0) value = 1; else fatal("%.200s line %d: Bad ControlPersist argument.", filename, linenum); if (*activep && *intptr == -1) { *intptr = value; options->control_persist_timeout = value2; } break; case oHashKnownHosts: intptr = &options->hash_known_hosts; goto parse_flag; case oTunnel: intptr = &options->tun_open; multistate_ptr = multistate_tunnel; goto parse_multistate; case oTunnelDevice: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); value = a2tun(arg, &value2); if (value == SSH_TUNID_ERR) fatal("%.200s line %d: Bad tun device.", filename, linenum); if (*activep) { options->tun_local = value; options->tun_remote = value2; } break; case oLocalCommand: charptr = &options->local_command; goto parse_command; case oPermitLocalCommand: intptr = &options->permit_local_command; goto parse_flag; case oVisualHostKey: intptr = &options->visual_host_key; goto parse_flag; case oIPQoS: arg = strdelim(&s); if ((value = parse_ipqos(arg)) == -1) fatal("%s line %d: Bad IPQoS value: %s", filename, linenum, arg); arg = strdelim(&s); if (arg == NULL) value2 = value; else if ((value2 = parse_ipqos(arg)) == -1) fatal("%s line %d: Bad IPQoS value: %s", filename, linenum, arg); if (*activep) { options->ip_qos_interactive = value; options->ip_qos_bulk = value2; } break; case oUseRoaming: intptr = &options->use_roaming; goto parse_flag; case oRequestTTY: intptr = &options->request_tty; multistate_ptr = multistate_requesttty; goto parse_multistate; case oIgnoreUnknown: charptr = &options->ignored_unknown; goto parse_string; case oProxyUseFdpass: intptr = &options->proxy_use_fdpass; goto parse_flag; case oCanonicalDomains: value = options->num_canonical_domains != 0; while ((arg = strdelim(&s)) != NULL && *arg != '\0') { valid_domain(arg, filename, linenum); if (!*activep || value) continue; if (options->num_canonical_domains >= MAX_CANON_DOMAINS) fatal("%s line %d: too many hostname suffixes.", filename, linenum); options->canonical_domains[ options->num_canonical_domains++] = xstrdup(arg); } break; case oCanonicalizePermittedCNAMEs: value = options->num_permitted_cnames != 0; while ((arg = strdelim(&s)) != NULL && *arg != '\0') { /* Either '*' for everything or 'list:list' */ if (strcmp(arg, "*") == 0) arg2 = arg; else { lowercase(arg); if ((arg2 = strchr(arg, ':')) == NULL || arg2[1] == '\0') { fatal("%s line %d: " "Invalid permitted CNAME \"%s\"", filename, linenum, arg); } *arg2 = '\0'; arg2++; } if (!*activep || value) continue; if (options->num_permitted_cnames >= MAX_CANON_DOMAINS) fatal("%s line %d: too many permitted CNAMEs.", filename, linenum); cname = options->permitted_cnames + options->num_permitted_cnames++; cname->source_list = xstrdup(arg); cname->target_list = xstrdup(arg2); } break; case oCanonicalizeHostname: intptr = &options->canonicalize_hostname; multistate_ptr = multistate_canonicalizehostname; goto parse_multistate; case oCanonicalizeMaxDots: intptr = &options->canonicalize_max_dots; goto parse_int; case oCanonicalizeFallbackLocal: intptr = &options->canonicalize_fallback_local; goto parse_flag; case oStreamLocalBindMask: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing StreamLocalBindMask argument.", filename, linenum); /* Parse mode in octal format */ value = strtol(arg, &endofnumber, 8); if (arg == endofnumber || value < 0 || value > 0777) fatal("%.200s line %d: Bad mask.", filename, linenum); options->fwd_opts.streamlocal_bind_mask = (mode_t)value; break; case oStreamLocalBindUnlink: intptr = &options->fwd_opts.streamlocal_bind_unlink; goto parse_flag; case oRevokedHostKeys: charptr = &options->revoked_host_keys; goto parse_string; case oFingerprintHash: intptr = &options->fingerprint_hash; arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing argument.", filename, linenum); if ((value = ssh_digest_alg_by_name(arg)) == -1) fatal("%.200s line %d: Invalid hash algorithm \"%s\".", filename, linenum, arg); if (*activep && *intptr == -1) *intptr = value; break; case oUpdateHostkeys: intptr = &options->update_hostkeys; multistate_ptr = multistate_yesnoask; goto parse_multistate; case oHostbasedKeyTypes: charptr = &options->hostbased_key_types; goto parse_keytypes; case oPubkeyAcceptedKeyTypes: charptr = &options->pubkey_key_types; goto parse_keytypes; case oDeprecated: debug("%s line %d: Deprecated option \"%s\"", filename, linenum, keyword); return 0; case oUnsupported: error("%s line %d: Unsupported option \"%s\"", filename, linenum, keyword); return 0; default: fatal("%s: Unimplemented opcode %d", __func__, opcode); } /* Check that there is no garbage at end of line. */ if ((arg = strdelim(&s)) != NULL && *arg != '\0') { fatal("%.200s line %d: garbage at end of line; \"%.200s\".", filename, linenum, arg); } return 0; } /* * Reads the config file and modifies the options accordingly. Options * should already be initialized before this call. This never returns if * there is an error. If the file does not exist, this returns 0. */ int read_config_file(const char *filename, struct passwd *pw, const char *host, const char *original_host, Options *options, int flags) { FILE *f; char line[1024]; int active, linenum; int bad_options = 0; if ((f = fopen(filename, "r")) == NULL) return 0; if (flags & SSHCONF_CHECKPERM) { struct stat sb; if (fstat(fileno(f), &sb) == -1) fatal("fstat %s: %s", filename, strerror(errno)); if (((sb.st_uid != 0 && sb.st_uid != getuid()) || (sb.st_mode & 022) != 0)) fatal("Bad owner or permissions on %s", filename); } debug("Reading configuration data %.200s", filename); /* * Mark that we are now processing the options. This flag is turned * on/off by Host specifications. */ active = 1; linenum = 0; while (fgets(line, sizeof(line), f)) { /* Update line number counter. */ linenum++; if (process_config_line(options, pw, host, original_host, line, filename, linenum, &active, flags) != 0) bad_options++; } fclose(f); if (bad_options > 0) fatal("%s: terminating, %d bad configuration options", filename, bad_options); return 1; } /* Returns 1 if a string option is unset or set to "none" or 0 otherwise. */ int option_clear_or_none(const char *o) { return o == NULL || strcasecmp(o, "none") == 0; } /* * Initializes options to special values that indicate that they have not yet * been set. Read_config_file will only set options with this value. Options * are processed in the following order: command line, user config file, * system config file. Last, fill_default_options is called. */ void initialize_options(Options * options) { memset(options, 'X', sizeof(*options)); options->forward_agent = -1; options->forward_x11 = -1; options->forward_x11_trusted = -1; options->forward_x11_timeout = -1; options->exit_on_forward_failure = -1; options->xauth_location = NULL; options->fwd_opts.gateway_ports = -1; options->fwd_opts.streamlocal_bind_mask = (mode_t)-1; options->fwd_opts.streamlocal_bind_unlink = -1; options->use_privileged_port = -1; options->rsa_authentication = -1; options->pubkey_authentication = -1; options->challenge_response_authentication = -1; options->gss_authentication = -1; options->gss_deleg_creds = -1; options->password_authentication = -1; options->kbd_interactive_authentication = -1; options->kbd_interactive_devices = NULL; options->rhosts_rsa_authentication = -1; options->hostbased_authentication = -1; options->batch_mode = -1; options->check_host_ip = -1; options->strict_host_key_checking = -1; options->compression = -1; options->tcp_keep_alive = -1; options->compression_level = -1; options->port = -1; options->address_family = -1; options->connection_attempts = -1; options->connection_timeout = -1; options->number_of_password_prompts = -1; options->cipher = -1; options->ciphers = NULL; options->macs = NULL; options->kex_algorithms = NULL; options->hostkeyalgorithms = NULL; options->protocol = SSH_PROTO_UNKNOWN; options->num_identity_files = 0; options->hostname = NULL; options->host_key_alias = NULL; options->proxy_command = NULL; options->user = NULL; options->escape_char = -1; options->num_system_hostfiles = 0; options->num_user_hostfiles = 0; options->local_forwards = NULL; options->num_local_forwards = 0; options->remote_forwards = NULL; options->num_remote_forwards = 0; options->clear_forwardings = -1; options->log_level = SYSLOG_LEVEL_NOT_SET; options->preferred_authentications = NULL; options->bind_address = NULL; options->pkcs11_provider = NULL; options->enable_ssh_keysign = - 1; options->no_host_authentication_for_localhost = - 1; options->identities_only = - 1; options->rekey_limit = - 1; options->rekey_interval = -1; options->verify_host_key_dns = -1; options->server_alive_interval = -1; options->server_alive_count_max = -1; options->num_send_env = 0; options->control_path = NULL; options->control_master = -1; options->control_persist = -1; options->control_persist_timeout = 0; options->hash_known_hosts = -1; options->tun_open = -1; options->tun_local = -1; options->tun_remote = -1; options->local_command = NULL; options->permit_local_command = -1; options->use_roaming = 0; options->visual_host_key = -1; options->ip_qos_interactive = -1; options->ip_qos_bulk = -1; options->request_tty = -1; options->proxy_use_fdpass = -1; options->ignored_unknown = NULL; options->num_canonical_domains = 0; options->num_permitted_cnames = 0; options->canonicalize_max_dots = -1; options->canonicalize_fallback_local = -1; options->canonicalize_hostname = -1; options->revoked_host_keys = NULL; options->fingerprint_hash = -1; options->update_hostkeys = -1; options->hostbased_key_types = NULL; options->pubkey_key_types = NULL; } /* * A petite version of fill_default_options() that just fills the options * needed for hostname canonicalization to proceed. */ void fill_default_options_for_canonicalization(Options *options) { if (options->canonicalize_max_dots == -1) options->canonicalize_max_dots = 1; if (options->canonicalize_fallback_local == -1) options->canonicalize_fallback_local = 1; if (options->canonicalize_hostname == -1) options->canonicalize_hostname = SSH_CANONICALISE_NO; } /* * Called after processing other sources of option data, this fills those * options for which no value has been specified with their default values. */ void fill_default_options(Options * options) { if (options->forward_agent == -1) options->forward_agent = 0; if (options->forward_x11 == -1) options->forward_x11 = 0; if (options->forward_x11_trusted == -1) options->forward_x11_trusted = 0; if (options->forward_x11_timeout == -1) options->forward_x11_timeout = 1200; if (options->exit_on_forward_failure == -1) options->exit_on_forward_failure = 0; if (options->xauth_location == NULL) options->xauth_location = _PATH_XAUTH; if (options->fwd_opts.gateway_ports == -1) options->fwd_opts.gateway_ports = 0; if (options->fwd_opts.streamlocal_bind_mask == (mode_t)-1) options->fwd_opts.streamlocal_bind_mask = 0177; if (options->fwd_opts.streamlocal_bind_unlink == -1) options->fwd_opts.streamlocal_bind_unlink = 0; if (options->use_privileged_port == -1) options->use_privileged_port = 0; if (options->rsa_authentication == -1) options->rsa_authentication = 1; if (options->pubkey_authentication == -1) options->pubkey_authentication = 1; if (options->challenge_response_authentication == -1) options->challenge_response_authentication = 1; if (options->gss_authentication == -1) options->gss_authentication = 0; if (options->gss_deleg_creds == -1) options->gss_deleg_creds = 0; if (options->password_authentication == -1) options->password_authentication = 1; if (options->kbd_interactive_authentication == -1) options->kbd_interactive_authentication = 1; if (options->rhosts_rsa_authentication == -1) options->rhosts_rsa_authentication = 0; if (options->hostbased_authentication == -1) options->hostbased_authentication = 0; if (options->batch_mode == -1) options->batch_mode = 0; if (options->check_host_ip == -1) options->check_host_ip = 1; if (options->strict_host_key_checking == -1) options->strict_host_key_checking = 2; /* 2 is default */ if (options->compression == -1) options->compression = 0; if (options->tcp_keep_alive == -1) options->tcp_keep_alive = 1; if (options->compression_level == -1) options->compression_level = 6; if (options->port == -1) options->port = 0; /* Filled in ssh_connect. */ if (options->address_family == -1) options->address_family = AF_UNSPEC; if (options->connection_attempts == -1) options->connection_attempts = 1; if (options->number_of_password_prompts == -1) options->number_of_password_prompts = 3; /* Selected in ssh_login(). */ if (options->cipher == -1) options->cipher = SSH_CIPHER_NOT_SET; /* options->hostkeyalgorithms, default set in myproposals.h */ if (options->protocol == SSH_PROTO_UNKNOWN) options->protocol = SSH_PROTO_2; if (options->num_identity_files == 0) { if (options->protocol & SSH_PROTO_1) { add_identity_file(options, "~/", _PATH_SSH_CLIENT_IDENTITY, 0); } if (options->protocol & SSH_PROTO_2) { add_identity_file(options, "~/", _PATH_SSH_CLIENT_ID_RSA, 0); add_identity_file(options, "~/", _PATH_SSH_CLIENT_ID_DSA, 0); #ifdef OPENSSL_HAS_ECC add_identity_file(options, "~/", _PATH_SSH_CLIENT_ID_ECDSA, 0); #endif add_identity_file(options, "~/", _PATH_SSH_CLIENT_ID_ED25519, 0); } } if (options->escape_char == -1) options->escape_char = '~'; if (options->num_system_hostfiles == 0) { options->system_hostfiles[options->num_system_hostfiles++] = xstrdup(_PATH_SSH_SYSTEM_HOSTFILE); options->system_hostfiles[options->num_system_hostfiles++] = xstrdup(_PATH_SSH_SYSTEM_HOSTFILE2); } if (options->num_user_hostfiles == 0) { options->user_hostfiles[options->num_user_hostfiles++] = xstrdup(_PATH_SSH_USER_HOSTFILE); options->user_hostfiles[options->num_user_hostfiles++] = xstrdup(_PATH_SSH_USER_HOSTFILE2); } if (options->log_level == SYSLOG_LEVEL_NOT_SET) options->log_level = SYSLOG_LEVEL_INFO; if (options->clear_forwardings == 1) clear_forwardings(options); if (options->no_host_authentication_for_localhost == - 1) options->no_host_authentication_for_localhost = 0; if (options->identities_only == -1) options->identities_only = 0; if (options->enable_ssh_keysign == -1) options->enable_ssh_keysign = 0; if (options->rekey_limit == -1) options->rekey_limit = 0; if (options->rekey_interval == -1) options->rekey_interval = 0; if (options->verify_host_key_dns == -1) options->verify_host_key_dns = 0; if (options->server_alive_interval == -1) options->server_alive_interval = 0; if (options->server_alive_count_max == -1) options->server_alive_count_max = 3; if (options->control_master == -1) options->control_master = 0; if (options->control_persist == -1) { options->control_persist = 0; options->control_persist_timeout = 0; } if (options->hash_known_hosts == -1) options->hash_known_hosts = 0; if (options->tun_open == -1) options->tun_open = SSH_TUNMODE_NO; if (options->tun_local == -1) options->tun_local = SSH_TUNID_ANY; if (options->tun_remote == -1) options->tun_remote = SSH_TUNID_ANY; if (options->permit_local_command == -1) options->permit_local_command = 0; options->use_roaming = 0; if (options->visual_host_key == -1) options->visual_host_key = 0; if (options->ip_qos_interactive == -1) options->ip_qos_interactive = IPTOS_LOWDELAY; if (options->ip_qos_bulk == -1) options->ip_qos_bulk = IPTOS_THROUGHPUT; if (options->request_tty == -1) options->request_tty = REQUEST_TTY_AUTO; if (options->proxy_use_fdpass == -1) options->proxy_use_fdpass = 0; if (options->canonicalize_max_dots == -1) options->canonicalize_max_dots = 1; if (options->canonicalize_fallback_local == -1) options->canonicalize_fallback_local = 1; if (options->canonicalize_hostname == -1) options->canonicalize_hostname = SSH_CANONICALISE_NO; if (options->fingerprint_hash == -1) options->fingerprint_hash = SSH_FP_HASH_DEFAULT; if (options->update_hostkeys == -1) options->update_hostkeys = 0; if (kex_assemble_names(KEX_CLIENT_ENCRYPT, &options->ciphers) != 0 || kex_assemble_names(KEX_CLIENT_MAC, &options->macs) != 0 || kex_assemble_names(KEX_CLIENT_KEX, &options->kex_algorithms) != 0 || kex_assemble_names(KEX_DEFAULT_PK_ALG, &options->hostbased_key_types) != 0 || kex_assemble_names(KEX_DEFAULT_PK_ALG, &options->pubkey_key_types) != 0) fatal("%s: kex_assemble_names failed", __func__); #define CLEAR_ON_NONE(v) \ do { \ if (option_clear_or_none(v)) { \ free(v); \ v = NULL; \ } \ } while(0) CLEAR_ON_NONE(options->local_command); CLEAR_ON_NONE(options->proxy_command); CLEAR_ON_NONE(options->control_path); CLEAR_ON_NONE(options->revoked_host_keys); /* options->user will be set in the main program if appropriate */ /* options->hostname will be set in the main program if appropriate */ /* options->host_key_alias should not be set by default */ /* options->preferred_authentications will be set in ssh */ } struct fwdarg { char *arg; int ispath; }; /* * parse_fwd_field * parses the next field in a port forwarding specification. * sets fwd to the parsed field and advances p past the colon * or sets it to NULL at end of string. * returns 0 on success, else non-zero. */ static int parse_fwd_field(char **p, struct fwdarg *fwd) { char *ep, *cp = *p; int ispath = 0; if (*cp == '\0') { *p = NULL; return -1; /* end of string */ } /* * A field escaped with square brackets is used literally. * XXX - allow ']' to be escaped via backslash? */ if (*cp == '[') { /* find matching ']' */ for (ep = cp + 1; *ep != ']' && *ep != '\0'; ep++) { if (*ep == '/') ispath = 1; } /* no matching ']' or not at end of field. */ if (ep[0] != ']' || (ep[1] != ':' && ep[1] != '\0')) return -1; /* NUL terminate the field and advance p past the colon */ *ep++ = '\0'; if (*ep != '\0') *ep++ = '\0'; fwd->arg = cp + 1; fwd->ispath = ispath; *p = ep; return 0; } for (cp = *p; *cp != '\0'; cp++) { switch (*cp) { case '\\': memmove(cp, cp + 1, strlen(cp + 1) + 1); if (*cp == '\0') return -1; break; case '/': ispath = 1; break; case ':': *cp++ = '\0'; goto done; } } done: fwd->arg = *p; fwd->ispath = ispath; *p = cp; return 0; } /* * parse_forward * parses a string containing a port forwarding specification of the form: * dynamicfwd == 0 * [listenhost:]listenport|listenpath:connecthost:connectport|connectpath * listenpath:connectpath * dynamicfwd == 1 * [listenhost:]listenport * returns number of arguments parsed or zero on error */ int parse_forward(struct Forward *fwd, const char *fwdspec, int dynamicfwd, int remotefwd) { struct fwdarg fwdargs[4]; char *p, *cp; int i; memset(fwd, 0, sizeof(*fwd)); memset(fwdargs, 0, sizeof(fwdargs)); cp = p = xstrdup(fwdspec); /* skip leading spaces */ while (isspace((u_char)*cp)) cp++; for (i = 0; i < 4; ++i) { if (parse_fwd_field(&cp, &fwdargs[i]) != 0) break; } /* Check for trailing garbage */ if (cp != NULL && *cp != '\0') { i = 0; /* failure */ } switch (i) { case 1: if (fwdargs[0].ispath) { fwd->listen_path = xstrdup(fwdargs[0].arg); fwd->listen_port = PORT_STREAMLOCAL; } else { fwd->listen_host = NULL; fwd->listen_port = a2port(fwdargs[0].arg); } fwd->connect_host = xstrdup("socks"); break; case 2: if (fwdargs[0].ispath && fwdargs[1].ispath) { fwd->listen_path = xstrdup(fwdargs[0].arg); fwd->listen_port = PORT_STREAMLOCAL; fwd->connect_path = xstrdup(fwdargs[1].arg); fwd->connect_port = PORT_STREAMLOCAL; } else if (fwdargs[1].ispath) { fwd->listen_host = NULL; fwd->listen_port = a2port(fwdargs[0].arg); fwd->connect_path = xstrdup(fwdargs[1].arg); fwd->connect_port = PORT_STREAMLOCAL; } else { fwd->listen_host = xstrdup(fwdargs[0].arg); fwd->listen_port = a2port(fwdargs[1].arg); fwd->connect_host = xstrdup("socks"); } break; case 3: if (fwdargs[0].ispath) { fwd->listen_path = xstrdup(fwdargs[0].arg); fwd->listen_port = PORT_STREAMLOCAL; fwd->connect_host = xstrdup(fwdargs[1].arg); fwd->connect_port = a2port(fwdargs[2].arg); } else if (fwdargs[2].ispath) { fwd->listen_host = xstrdup(fwdargs[0].arg); fwd->listen_port = a2port(fwdargs[1].arg); fwd->connect_path = xstrdup(fwdargs[2].arg); fwd->connect_port = PORT_STREAMLOCAL; } else { fwd->listen_host = NULL; fwd->listen_port = a2port(fwdargs[0].arg); fwd->connect_host = xstrdup(fwdargs[1].arg); fwd->connect_port = a2port(fwdargs[2].arg); } break; case 4: fwd->listen_host = xstrdup(fwdargs[0].arg); fwd->listen_port = a2port(fwdargs[1].arg); fwd->connect_host = xstrdup(fwdargs[2].arg); fwd->connect_port = a2port(fwdargs[3].arg); break; default: i = 0; /* failure */ } free(p); if (dynamicfwd) { if (!(i == 1 || i == 2)) goto fail_free; } else { if (!(i == 3 || i == 4)) { if (fwd->connect_path == NULL && fwd->listen_path == NULL) goto fail_free; } if (fwd->connect_port <= 0 && fwd->connect_path == NULL) goto fail_free; } if ((fwd->listen_port < 0 && fwd->listen_path == NULL) || (!remotefwd && fwd->listen_port == 0)) goto fail_free; if (fwd->connect_host != NULL && strlen(fwd->connect_host) >= NI_MAXHOST) goto fail_free; /* XXX - if connecting to a remote socket, max sun len may not match this host */ if (fwd->connect_path != NULL && strlen(fwd->connect_path) >= PATH_MAX_SUN) goto fail_free; if (fwd->listen_host != NULL && strlen(fwd->listen_host) >= NI_MAXHOST) goto fail_free; if (fwd->listen_path != NULL && strlen(fwd->listen_path) >= PATH_MAX_SUN) goto fail_free; return (i); fail_free: free(fwd->connect_host); fwd->connect_host = NULL; free(fwd->connect_path); fwd->connect_path = NULL; free(fwd->listen_host); fwd->listen_host = NULL; free(fwd->listen_path); fwd->listen_path = NULL; return (0); } /* XXX the following is a near-vebatim copy from servconf.c; refactor */ static const char * fmt_multistate_int(int val, const struct multistate *m) { u_int i; for (i = 0; m[i].key != NULL; i++) { if (m[i].value == val) return m[i].key; } return "UNKNOWN"; } static const char * fmt_intarg(OpCodes code, int val) { if (val == -1) return "unset"; switch (code) { case oAddressFamily: return fmt_multistate_int(val, multistate_addressfamily); case oVerifyHostKeyDNS: case oStrictHostKeyChecking: case oUpdateHostkeys: return fmt_multistate_int(val, multistate_yesnoask); case oControlMaster: return fmt_multistate_int(val, multistate_controlmaster); case oTunnel: return fmt_multistate_int(val, multistate_tunnel); case oRequestTTY: return fmt_multistate_int(val, multistate_requesttty); case oCanonicalizeHostname: return fmt_multistate_int(val, multistate_canonicalizehostname); case oFingerprintHash: return ssh_digest_alg_name(val); case oProtocol: switch (val) { case SSH_PROTO_1: return "1"; case SSH_PROTO_2: return "2"; case (SSH_PROTO_1|SSH_PROTO_2): return "2,1"; default: return "UNKNOWN"; } default: switch (val) { case 0: return "no"; case 1: return "yes"; default: return "UNKNOWN"; } } } static const char * lookup_opcode_name(OpCodes code) { u_int i; for (i = 0; keywords[i].name != NULL; i++) if (keywords[i].opcode == code) return(keywords[i].name); return "UNKNOWN"; } static void dump_cfg_int(OpCodes code, int val) { printf("%s %d\n", lookup_opcode_name(code), val); } static void dump_cfg_fmtint(OpCodes code, int val) { printf("%s %s\n", lookup_opcode_name(code), fmt_intarg(code, val)); } static void dump_cfg_string(OpCodes code, const char *val) { if (val == NULL) return; printf("%s %s\n", lookup_opcode_name(code), val); } static void dump_cfg_strarray(OpCodes code, u_int count, char **vals) { u_int i; for (i = 0; i < count; i++) printf("%s %s\n", lookup_opcode_name(code), vals[i]); } static void dump_cfg_strarray_oneline(OpCodes code, u_int count, char **vals) { u_int i; printf("%s", lookup_opcode_name(code)); for (i = 0; i < count; i++) printf(" %s", vals[i]); printf("\n"); } static void dump_cfg_forwards(OpCodes code, u_int count, const struct Forward *fwds) { const struct Forward *fwd; u_int i; /* oDynamicForward */ for (i = 0; i < count; i++) { fwd = &fwds[i]; if (code == oDynamicForward && strcmp(fwd->connect_host, "socks") != 0) continue; if (code == oLocalForward && strcmp(fwd->connect_host, "socks") == 0) continue; printf("%s", lookup_opcode_name(code)); if (fwd->listen_port == PORT_STREAMLOCAL) printf(" %s", fwd->listen_path); else if (fwd->listen_host == NULL) printf(" %d", fwd->listen_port); else { printf(" [%s]:%d", fwd->listen_host, fwd->listen_port); } if (code != oDynamicForward) { if (fwd->connect_port == PORT_STREAMLOCAL) printf(" %s", fwd->connect_path); else if (fwd->connect_host == NULL) printf(" %d", fwd->connect_port); else { printf(" [%s]:%d", fwd->connect_host, fwd->connect_port); } } printf("\n"); } } void dump_client_config(Options *o, const char *host) { int i; char vbuf[5]; /* Most interesting options first: user, host, port */ dump_cfg_string(oUser, o->user); dump_cfg_string(oHostName, host); dump_cfg_int(oPort, o->port); /* Flag options */ dump_cfg_fmtint(oAddressFamily, o->address_family); dump_cfg_fmtint(oBatchMode, o->batch_mode); dump_cfg_fmtint(oCanonicalizeFallbackLocal, o->canonicalize_fallback_local); dump_cfg_fmtint(oCanonicalizeHostname, o->canonicalize_hostname); dump_cfg_fmtint(oChallengeResponseAuthentication, o->challenge_response_authentication); dump_cfg_fmtint(oCheckHostIP, o->check_host_ip); dump_cfg_fmtint(oCompression, o->compression); dump_cfg_fmtint(oControlMaster, o->control_master); dump_cfg_fmtint(oEnableSSHKeysign, o->enable_ssh_keysign); dump_cfg_fmtint(oExitOnForwardFailure, o->exit_on_forward_failure); dump_cfg_fmtint(oFingerprintHash, o->fingerprint_hash); dump_cfg_fmtint(oForwardAgent, o->forward_agent); dump_cfg_fmtint(oForwardX11, o->forward_x11); dump_cfg_fmtint(oForwardX11Trusted, o->forward_x11_trusted); dump_cfg_fmtint(oGatewayPorts, o->fwd_opts.gateway_ports); #ifdef GSSAPI dump_cfg_fmtint(oGssAuthentication, o->gss_authentication); dump_cfg_fmtint(oGssDelegateCreds, o->gss_deleg_creds); #endif /* GSSAPI */ dump_cfg_fmtint(oHashKnownHosts, o->hash_known_hosts); dump_cfg_fmtint(oHostbasedAuthentication, o->hostbased_authentication); dump_cfg_fmtint(oIdentitiesOnly, o->identities_only); dump_cfg_fmtint(oKbdInteractiveAuthentication, o->kbd_interactive_authentication); dump_cfg_fmtint(oNoHostAuthenticationForLocalhost, o->no_host_authentication_for_localhost); dump_cfg_fmtint(oPasswordAuthentication, o->password_authentication); dump_cfg_fmtint(oPermitLocalCommand, o->permit_local_command); dump_cfg_fmtint(oProtocol, o->protocol); dump_cfg_fmtint(oProxyUseFdpass, o->proxy_use_fdpass); dump_cfg_fmtint(oPubkeyAuthentication, o->pubkey_authentication); dump_cfg_fmtint(oRequestTTY, o->request_tty); dump_cfg_fmtint(oRhostsRSAAuthentication, o->rhosts_rsa_authentication); dump_cfg_fmtint(oRSAAuthentication, o->rsa_authentication); dump_cfg_fmtint(oStreamLocalBindUnlink, o->fwd_opts.streamlocal_bind_unlink); dump_cfg_fmtint(oStrictHostKeyChecking, o->strict_host_key_checking); dump_cfg_fmtint(oTCPKeepAlive, o->tcp_keep_alive); dump_cfg_fmtint(oTunnel, o->tun_open); dump_cfg_fmtint(oUsePrivilegedPort, o->use_privileged_port); dump_cfg_fmtint(oVerifyHostKeyDNS, o->verify_host_key_dns); dump_cfg_fmtint(oVisualHostKey, o->visual_host_key); dump_cfg_fmtint(oUpdateHostkeys, o->update_hostkeys); /* Integer options */ dump_cfg_int(oCanonicalizeMaxDots, o->canonicalize_max_dots); dump_cfg_int(oCompressionLevel, o->compression_level); dump_cfg_int(oConnectionAttempts, o->connection_attempts); dump_cfg_int(oForwardX11Timeout, o->forward_x11_timeout); dump_cfg_int(oNumberOfPasswordPrompts, o->number_of_password_prompts); dump_cfg_int(oServerAliveCountMax, o->server_alive_count_max); dump_cfg_int(oServerAliveInterval, o->server_alive_interval); /* String options */ dump_cfg_string(oBindAddress, o->bind_address); dump_cfg_string(oCiphers, o->ciphers ? o->ciphers : KEX_CLIENT_ENCRYPT); dump_cfg_string(oControlPath, o->control_path); dump_cfg_string(oHostKeyAlgorithms, o->hostkeyalgorithms ? o->hostkeyalgorithms : KEX_DEFAULT_PK_ALG); dump_cfg_string(oHostKeyAlias, o->host_key_alias); dump_cfg_string(oHostbasedKeyTypes, o->hostbased_key_types); dump_cfg_string(oKbdInteractiveDevices, o->kbd_interactive_devices); dump_cfg_string(oKexAlgorithms, o->kex_algorithms ? o->kex_algorithms : KEX_CLIENT_KEX); dump_cfg_string(oLocalCommand, o->local_command); dump_cfg_string(oLogLevel, log_level_name(o->log_level)); dump_cfg_string(oMacs, o->macs ? o->macs : KEX_CLIENT_MAC); dump_cfg_string(oPKCS11Provider, o->pkcs11_provider); dump_cfg_string(oPreferredAuthentications, o->preferred_authentications); dump_cfg_string(oProxyCommand, o->proxy_command); dump_cfg_string(oRevokedHostKeys, o->revoked_host_keys); dump_cfg_string(oXAuthLocation, o->xauth_location); /* Forwards */ dump_cfg_forwards(oDynamicForward, o->num_local_forwards, o->local_forwards); dump_cfg_forwards(oLocalForward, o->num_local_forwards, o->local_forwards); dump_cfg_forwards(oRemoteForward, o->num_remote_forwards, o->remote_forwards); /* String array options */ dump_cfg_strarray(oIdentityFile, o->num_identity_files, o->identity_files); dump_cfg_strarray_oneline(oCanonicalDomains, o->num_canonical_domains, o->canonical_domains); dump_cfg_strarray_oneline(oGlobalKnownHostsFile, o->num_system_hostfiles, o->system_hostfiles); dump_cfg_strarray_oneline(oUserKnownHostsFile, o->num_user_hostfiles, o->user_hostfiles); dump_cfg_strarray(oSendEnv, o->num_send_env, o->send_env); /* Special cases */ /* oConnectTimeout */ if (o->connection_timeout == -1) printf("connecttimeout none\n"); else dump_cfg_int(oConnectTimeout, o->connection_timeout); /* oTunnelDevice */ printf("tunneldevice"); if (o->tun_local == SSH_TUNID_ANY) printf(" any"); else printf(" %d", o->tun_local); if (o->tun_remote == SSH_TUNID_ANY) printf(":any"); else printf(":%d", o->tun_remote); printf("\n"); /* oCanonicalizePermittedCNAMEs */ if ( o->num_permitted_cnames > 0) { printf("canonicalizePermittedcnames"); for (i = 0; i < o->num_permitted_cnames; i++) { printf(" %s:%s", o->permitted_cnames[i].source_list, o->permitted_cnames[i].target_list); } printf("\n"); } /* oCipher */ if (o->cipher != SSH_CIPHER_NOT_SET) printf("Cipher %s\n", cipher_name(o->cipher)); /* oControlPersist */ if (o->control_persist == 0 || o->control_persist_timeout == 0) dump_cfg_fmtint(oControlPersist, o->control_persist); else dump_cfg_int(oControlPersist, o->control_persist_timeout); /* oEscapeChar */ if (o->escape_char == SSH_ESCAPECHAR_NONE) printf("escapechar none\n"); else { vis(vbuf, o->escape_char, VIS_WHITE, 0); printf("escapechar %s\n", vbuf); } /* oIPQoS */ printf("ipqos %s ", iptos2str(o->ip_qos_interactive)); printf("%s\n", iptos2str(o->ip_qos_bulk)); /* oRekeyLimit */ printf("rekeylimit %lld %d\n", (long long)o->rekey_limit, o->rekey_interval); /* oStreamLocalBindMask */ printf("streamlocalbindmask 0%o\n", o->fwd_opts.streamlocal_bind_mask); }