X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/b08b7370a27055571f8de1124ec18e448ae0b150..9794d0089c075188de1c7a752a61e7efc9e227bc:/readconf.c diff --git a/readconf.c b/readconf.c index 86d28bc8..df5e566a 100644 --- a/readconf.c +++ b/readconf.c @@ -1,3 +1,4 @@ +/* $OpenBSD: readconf.c,v 1.152 2006/07/05 02:42:09 stevesk Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -12,7 +13,14 @@ */ #include "includes.h" -RCSID("$OpenBSD: readconf.c,v 1.124 2003/10/14 19:42:10 jakob Exp $"); + +#include +#include +#include + +#include + +#include #include "ssh.h" #include "xmalloc.h" @@ -70,6 +78,10 @@ RCSID("$OpenBSD: readconf.c,v 1.124 2003/10/14 19:42:10 jakob Exp $"); Cipher none PasswordAuthentication no + Host vpn.fake.com + Tunnel yes + TunnelDevice 3 + # Defaults for various options Host * ForwardAgent no @@ -78,7 +90,7 @@ RCSID("$OpenBSD: readconf.c,v 1.124 2003/10/14 19:42:10 jakob Exp $"); RSAAuthentication yes RhostsRSAAuthentication yes StrictHostKeyChecking yes - KeepAlives no + TcpKeepAlive no IdentityFile ~/.ssh/identity Port 22 EscapeChar ~ @@ -96,7 +108,7 @@ typedef enum { oUser, oHost, oEscapeChar, oRhostsRSAAuthentication, oProxyCommand, oGlobalKnownHostsFile, oUserKnownHostsFile, oConnectionAttempts, oBatchMode, oCheckHostIP, oStrictHostKeyChecking, oCompression, - oCompressionLevel, oKeepAlives, oNumberOfPasswordPrompts, + oCompressionLevel, oTCPKeepAlive, oNumberOfPasswordPrompts, oUsePrivilegedPort, oLogLevel, oCiphers, oProtocol, oMacs, oGlobalKnownHostsFile2, oUserKnownHostsFile2, oPubkeyAuthentication, oKbdInteractiveAuthentication, oKbdInteractiveDevices, oHostKeyAlias, @@ -105,6 +117,9 @@ typedef enum { oClearAllForwardings, oNoHostAuthenticationForLocalhost, oEnableSSHKeysign, oRekeyLimit, oVerifyHostKeyDNS, oConnectTimeout, oAddressFamily, oGssAuthentication, oGssDelegateCreds, + oServerAliveInterval, oServerAliveCountMax, oIdentitiesOnly, + oSendEnv, oControlPath, oControlMaster, oHashKnownHosts, + oTunnel, oTunnelDevice, oLocalCommand, oPermitLocalCommand, oDeprecated, oUnsupported } OpCodes; @@ -146,6 +161,7 @@ static struct { { "usersh", oDeprecated }, { "identityfile", oIdentityFile }, { "identityfile2", oIdentityFile }, /* alias */ + { "identitiesonly", oIdentitiesOnly }, { "hostname", oHostName }, { "hostkeyalias", oHostKeyAlias }, { "proxycommand", oProxyCommand }, @@ -169,7 +185,8 @@ static struct { { "stricthostkeychecking", oStrictHostKeyChecking }, { "compression", oCompression }, { "compressionlevel", oCompressionLevel }, - { "keepalive", oKeepAlives }, + { "tcpkeepalive", oTCPKeepAlive }, + { "keepalive", oTCPKeepAlive }, /* obsolete */ { "numberofpasswordprompts", oNumberOfPasswordPrompts }, { "loglevel", oLogLevel }, { "dynamicforward", oDynamicForward }, @@ -188,6 +205,16 @@ static struct { { "rekeylimit", oRekeyLimit }, { "connecttimeout", oConnectTimeout }, { "addressfamily", oAddressFamily }, + { "serveraliveinterval", oServerAliveInterval }, + { "serveralivecountmax", oServerAliveCountMax }, + { "sendenv", oSendEnv }, + { "controlpath", oControlPath }, + { "controlmaster", oControlMaster }, + { "hashknownhosts", oHashKnownHosts }, + { "tunnel", oTunnel }, + { "tunneldevice", oTunnelDevice }, + { "localcommand", oLocalCommand }, + { "permitlocalcommand", oPermitLocalCommand }, { NULL, oBadOption } }; @@ -197,21 +224,23 @@ static struct { */ void -add_local_forward(Options *options, u_short port, const char *host, - u_short host_port) +add_local_forward(Options *options, const Forward *newfwd) { Forward *fwd; #ifndef NO_IPPORT_RESERVED_CONCEPT extern uid_t original_real_uid; - if (port < IPPORT_RESERVED && original_real_uid != 0) + if (newfwd->listen_port < IPPORT_RESERVED && original_real_uid != 0) fatal("Privileged ports can only be forwarded by root."); #endif if (options->num_local_forwards >= SSH_MAX_FORWARDS_PER_DIRECTION) fatal("Too many local forwards (max %d).", SSH_MAX_FORWARDS_PER_DIRECTION); fwd = &options->local_forwards[options->num_local_forwards++]; - fwd->port = port; - fwd->host = xstrdup(host); - fwd->host_port = host_port; + + fwd->listen_host = (newfwd->listen_host == NULL) ? + NULL : xstrdup(newfwd->listen_host); + fwd->listen_port = newfwd->listen_port; + fwd->connect_host = xstrdup(newfwd->connect_host); + fwd->connect_port = newfwd->connect_port; } /* @@ -220,17 +249,19 @@ add_local_forward(Options *options, u_short port, const char *host, */ void -add_remote_forward(Options *options, u_short port, const char *host, - u_short host_port) +add_remote_forward(Options *options, const Forward *newfwd) { Forward *fwd; if (options->num_remote_forwards >= SSH_MAX_FORWARDS_PER_DIRECTION) fatal("Too many remote forwards (max %d).", SSH_MAX_FORWARDS_PER_DIRECTION); fwd = &options->remote_forwards[options->num_remote_forwards++]; - fwd->port = port; - fwd->host = xstrdup(host); - fwd->host_port = host_port; + + fwd->listen_host = (newfwd->listen_host == NULL) ? + NULL : xstrdup(newfwd->listen_host); + fwd->listen_port = newfwd->listen_port; + fwd->connect_host = xstrdup(newfwd->connect_host); + fwd->connect_port = newfwd->connect_port; } static void @@ -238,12 +269,19 @@ clear_forwardings(Options *options) { int i; - for (i = 0; i < options->num_local_forwards; i++) - xfree(options->local_forwards[i].host); + for (i = 0; i < options->num_local_forwards; i++) { + if (options->local_forwards[i].listen_host != NULL) + xfree(options->local_forwards[i].listen_host); + xfree(options->local_forwards[i].connect_host); + } options->num_local_forwards = 0; - for (i = 0; i < options->num_remote_forwards; i++) - xfree(options->remote_forwards[i].host); + for (i = 0; i < options->num_remote_forwards; i++) { + if (options->remote_forwards[i].listen_host != NULL) + xfree(options->remote_forwards[i].listen_host); + xfree(options->remote_forwards[i].connect_host); + } options->num_remote_forwards = 0; + options->tun_open = SSH_TUNMODE_NO; } /* @@ -275,14 +313,14 @@ process_config_line(Options *options, const char *host, char *line, const char *filename, int linenum, int *activep) { - char buf[256], *s, **charptr, *endofnumber, *keyword, *arg; - int opcode, *intptr, value; + char *s, **charptr, *endofnumber, *keyword, *arg, *arg2, fwdarg[256]; + int opcode, *intptr, value, value2, scale; + long long orig, val64; size_t len; - u_short fwd_port, fwd_host_port; - char sfwd_host_port[6]; + Forward fwd; /* Strip trailing whitespace */ - for(len = strlen(line) - 1; len > 0; len--) { + for (len = strlen(line) - 1; len > 0; len--) { if (strchr(WHITESPACE, line[len]) == NULL) break; line[len] = '\0'; @@ -290,7 +328,8 @@ process_config_line(Options *options, const char *host, s = line; /* Get the keyword. (Each line is supposed to begin with a keyword). */ - keyword = strdelim(&s); + if ((keyword = strdelim(&s)) == NULL) + return 0; /* Ignore leading whitespace. */ if (*keyword == '\0') keyword = strdelim(&s); @@ -306,7 +345,7 @@ process_config_line(Options *options, const char *host, /* NOTREACHED */ case oConnectTimeout: intptr = &options->connection_timeout; -/* parse_time: */ +parse_time: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%s line %d: missing time value.", @@ -401,10 +440,11 @@ parse_flag: case oVerifyHostKeyDNS: intptr = &options->verify_host_key_dns; - goto parse_flag; + goto parse_yesnoask; case oStrictHostKeyChecking: intptr = &options->strict_host_key_checking; +parse_yesnoask: arg = strdelim(&s); if (!arg || *arg == '\0') fatal("%.200s line %d: Missing yes/no/ask argument.", @@ -426,8 +466,8 @@ parse_flag: intptr = &options->compression; goto parse_flag; - case oKeepAlives: - intptr = &options->keepalives; + case oTCPKeepAlive: + intptr = &options->tcp_keep_alive; goto parse_flag; case oNoHostAuthenticationForLocalhost: @@ -449,22 +489,36 @@ parse_flag: fatal("%.200s line %d: Missing argument.", filename, linenum); if (arg[0] < '0' || arg[0] > '9') fatal("%.200s line %d: Bad number.", filename, linenum); - value = strtol(arg, &endofnumber, 10); + orig = val64 = strtoll(arg, &endofnumber, 10); if (arg == endofnumber) fatal("%.200s line %d: Bad number.", filename, linenum); switch (toupper(*endofnumber)) { + case '\0': + scale = 1; + break; case 'K': - value *= 1<<10; + scale = 1<<10; break; case 'M': - value *= 1<<20; + scale = 1<<20; break; case 'G': - value *= 1<<30; + scale = 1<<30; break; + default: + fatal("%.200s line %d: Invalid RekeyLimit suffix", + filename, linenum); } + val64 *= scale; + /* detect integer wrap and too-large limits */ + if ((val64 / scale) != orig || val64 > INT_MAX) + fatal("%.200s line %d: RekeyLimit too large", + filename, linenum); + if (val64 < 16) + fatal("%.200s line %d: RekeyLimit too small", + filename, linenum); if (*activep && *intptr == -1) - *intptr = value; + *intptr = (int)val64; break; case oIdentityFile: @@ -533,9 +587,10 @@ parse_string: goto parse_string; case oProxyCommand: + charptr = &options->proxy_command; +parse_command: if (s == NULL) fatal("%.200s line %d: Missing argument.", filename, linenum); - charptr = &options->proxy_command; len = strspn(s, WHITESPACE "="); if (*activep && *charptr == NULL) *charptr = xstrdup(s + len); @@ -635,30 +690,26 @@ parse_int: case oLocalForward: case oRemoteForward: arg = strdelim(&s); - if (!arg || *arg == '\0') + if (arg == NULL || *arg == '\0') fatal("%.200s line %d: Missing port argument.", filename, linenum); - if ((fwd_port = a2port(arg)) == 0) - fatal("%.200s line %d: Bad listen port.", - filename, linenum); - arg = strdelim(&s); - if (!arg || *arg == '\0') - fatal("%.200s line %d: Missing second argument.", + arg2 = strdelim(&s); + if (arg2 == NULL || *arg2 == '\0') + fatal("%.200s line %d: Missing target argument.", filename, linenum); - if (sscanf(arg, "%255[^:]:%5[0-9]", buf, sfwd_host_port) != 2 && - sscanf(arg, "%255[^/]/%5[0-9]", buf, sfwd_host_port) != 2) + + /* construct a string for parse_forward */ + snprintf(fwdarg, sizeof(fwdarg), "%s:%s", arg, arg2); + + if (parse_forward(&fwd, fwdarg) == 0) fatal("%.200s line %d: Bad forwarding specification.", filename, linenum); - if ((fwd_host_port = a2port(sfwd_host_port)) == 0) - fatal("%.200s line %d: Bad forwarding port.", - filename, linenum); + if (*activep) { if (opcode == oLocalForward) - add_local_forward(options, fwd_port, buf, - fwd_host_port); + add_local_forward(options, &fwd); else if (opcode == oRemoteForward) - add_remote_forward(options, fwd_port, buf, - fwd_host_port); + add_remote_forward(options, &fwd); } break; @@ -667,12 +718,25 @@ parse_int: if (!arg || *arg == '\0') fatal("%.200s line %d: Missing port argument.", filename, linenum); - fwd_port = a2port(arg); - if (fwd_port == 0) + memset(&fwd, '\0', sizeof(fwd)); + fwd.connect_host = "socks"; + fwd.listen_host = hpdelim(&arg); + if (fwd.listen_host == NULL || + strlen(fwd.listen_host) >= NI_MAXHOST) + fatal("%.200s line %d: Bad forwarding specification.", + filename, linenum); + if (arg) { + fwd.listen_port = a2port(arg); + fwd.listen_host = cleanhostname(fwd.listen_host); + } else { + fwd.listen_port = a2port(fwd.listen_host); + fwd.listen_host = NULL; + } + if (fwd.listen_port == 0) fatal("%.200s line %d: Badly formatted port number.", filename, linenum); if (*activep) - add_local_forward(options, fwd_port, "socks", 0); + add_local_forward(options, &fwd); break; case oClearAllForwardings: @@ -714,6 +778,9 @@ parse_int: case oAddressFamily: arg = strdelim(&s); + if (!arg || *arg == '\0') + fatal("%s line %d: missing address family.", + filename, linenum); intptr = &options->address_family; if (strcasecmp(arg, "inet") == 0) value = AF_INET; @@ -731,6 +798,108 @@ parse_int: 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; + arg = strdelim(&s); + if (!arg || *arg == '\0') + fatal("%.200s line %d: Missing ControlMaster argument.", + filename, linenum); + value = 0; /* To avoid compiler warning... */ + if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0) + value = SSHCTL_MASTER_YES; + else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0) + value = SSHCTL_MASTER_NO; + else if (strcmp(arg, "auto") == 0) + value = SSHCTL_MASTER_AUTO; + else if (strcmp(arg, "ask") == 0) + value = SSHCTL_MASTER_ASK; + else if (strcmp(arg, "autoask") == 0) + value = SSHCTL_MASTER_AUTO_ASK; + else + fatal("%.200s line %d: Bad ControlMaster argument.", + filename, linenum); + if (*activep && *intptr == -1) + *intptr = value; + break; + + case oHashKnownHosts: + intptr = &options->hash_known_hosts; + goto parse_flag; + + case oTunnel: + intptr = &options->tun_open; + arg = strdelim(&s); + if (!arg || *arg == '\0') + fatal("%s line %d: Missing yes/point-to-point/" + "ethernet/no argument.", filename, linenum); + value = 0; /* silence compiler */ + if (strcasecmp(arg, "ethernet") == 0) + value = SSH_TUNMODE_ETHERNET; + else if (strcasecmp(arg, "point-to-point") == 0) + value = SSH_TUNMODE_POINTOPOINT; + else if (strcasecmp(arg, "yes") == 0) + value = SSH_TUNMODE_DEFAULT; + else if (strcasecmp(arg, "no") == 0) + value = SSH_TUNMODE_NO; + else + fatal("%s line %d: Bad yes/point-to-point/ethernet/" + "no argument: %s", filename, linenum, arg); + if (*activep) + *intptr = value; + break; + + 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 oDeprecated: debug("%s line %d: Deprecated option \"%s\"", filename, linenum, keyword); @@ -748,7 +917,7 @@ parse_int: /* 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); + filename, linenum, arg); } return 0; } @@ -761,7 +930,8 @@ parse_int: */ int -read_config_file(const char *filename, const char *host, Options *options) +read_config_file(const char *filename, const char *host, Options *options, + int checkperm) { FILE *f; char line[1024]; @@ -769,10 +939,19 @@ read_config_file(const char *filename, const char *host, Options *options) int bad_options = 0; /* Open the file. */ - f = fopen(filename, "r"); - if (!f) + if ((f = fopen(filename, "r")) == NULL) return 0; + if (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); /* @@ -825,7 +1004,7 @@ initialize_options(Options * options) options->check_host_ip = -1; options->strict_host_key_checking = -1; options->compression = -1; - options->keepalives = -1; + options->tcp_keep_alive = -1; options->compression_level = -1; options->port = -1; options->address_family = -1; @@ -856,8 +1035,20 @@ initialize_options(Options * options) options->smartcard_device = NULL; options->enable_ssh_keysign = - 1; options->no_host_authentication_for_localhost = - 1; + options->identities_only = - 1; options->rekey_limit = - 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->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; } /* @@ -908,8 +1099,8 @@ fill_default_options(Options * options) options->strict_host_key_checking = 2; /* 2 is default */ if (options->compression == -1) options->compression = 0; - if (options->keepalives == -1) - options->keepalives = 1; + if (options->tcp_keep_alive == -1) + options->tcp_keep_alive = 1; if (options->compression_level == -1) options->compression_level = 6; if (options->port == -1) @@ -966,15 +1157,99 @@ fill_default_options(Options * options) 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->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->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->local_command should not be set by default */ /* options->proxy_command should not be set by default */ /* 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 */ } + +/* + * parse_forward + * parses a string containing a port forwarding specification of the form: + * [listenhost:]listenport:connecthost:connectport + * returns number of arguments parsed or zero on error + */ +int +parse_forward(Forward *fwd, const char *fwdspec) +{ + int i; + char *p, *cp, *fwdarg[4]; + + memset(fwd, '\0', sizeof(*fwd)); + + cp = p = xstrdup(fwdspec); + + /* skip leading spaces */ + while (*cp && isspace(*cp)) + cp++; + + for (i = 0; i < 4; ++i) + if ((fwdarg[i] = hpdelim(&cp)) == NULL) + break; + + /* Check for trailing garbage in 4-arg case*/ + if (cp != NULL) + i = 0; /* failure */ + + switch (i) { + case 3: + fwd->listen_host = NULL; + fwd->listen_port = a2port(fwdarg[0]); + fwd->connect_host = xstrdup(cleanhostname(fwdarg[1])); + fwd->connect_port = a2port(fwdarg[2]); + break; + + case 4: + fwd->listen_host = xstrdup(cleanhostname(fwdarg[0])); + fwd->listen_port = a2port(fwdarg[1]); + fwd->connect_host = xstrdup(cleanhostname(fwdarg[2])); + fwd->connect_port = a2port(fwdarg[3]); + break; + default: + i = 0; /* failure */ + } + + xfree(p); + + if (fwd->listen_port == 0 && fwd->connect_port == 0) + goto fail_free; + + if (fwd->connect_host != NULL && + strlen(fwd->connect_host) >= NI_MAXHOST) + goto fail_free; + + return (i); + + fail_free: + if (fwd->connect_host != NULL) + xfree(fwd->connect_host); + if (fwd->listen_host != NULL) + xfree(fwd->listen_host); + return (0); +}