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Annotation of src/usr.bin/ssh/auth2.c, Revision 1.8.2.2

1.1       markus      1: /*
                      2:  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
                      3:  *
                      4:  * Redistribution and use in source and binary forms, with or without
                      5:  * modification, are permitted provided that the following conditions
                      6:  * are met:
                      7:  * 1. Redistributions of source code must retain the above copyright
                      8:  *    notice, this list of conditions and the following disclaimer.
                      9:  * 2. Redistributions in binary form must reproduce the above copyright
                     10:  *    notice, this list of conditions and the following disclaimer in the
                     11:  *    documentation and/or other materials provided with the distribution.
                     12:  *
                     13:  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
                     14:  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
                     15:  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
                     16:  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
                     17:  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
                     18:  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
                     19:  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
                     20:  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
                     21:  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
                     22:  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
                     23:  */
1.8.2.2 ! jason      24:
1.1       markus     25: #include "includes.h"
1.8.2.2 ! jason      26: RCSID("$OpenBSD: auth2.c,v 1.20 2000/10/14 12:16:56 markus Exp $");
1.1       markus     27:
                     28: #include <openssl/dsa.h>
                     29: #include <openssl/rsa.h>
                     30: #include <openssl/evp.h>
                     31:
                     32: #include "xmalloc.h"
                     33: #include "rsa.h"
                     34: #include "ssh.h"
                     35: #include "pty.h"
                     36: #include "packet.h"
                     37: #include "buffer.h"
                     38: #include "servconf.h"
                     39: #include "compat.h"
                     40: #include "channels.h"
                     41: #include "bufaux.h"
                     42: #include "ssh2.h"
                     43: #include "auth.h"
                     44: #include "session.h"
                     45: #include "dispatch.h"
                     46: #include "auth.h"
                     47: #include "key.h"
                     48: #include "kex.h"
                     49:
                     50: #include "dsa.h"
                     51: #include "uidswap.h"
1.8.2.1   jason      52: #include "auth-options.h"
1.1       markus     53:
                     54: /* import */
                     55: extern ServerOptions options;
                     56: extern unsigned char *session_id2;
                     57: extern int session_id2_len;
                     58:
1.8.2.2 ! jason      59: static Authctxt        *x_authctxt = NULL;
        !            60: static int one = 1;
        !            61:
        !            62: typedef struct Authmethod Authmethod;
        !            63: struct Authmethod {
        !            64:        char    *name;
        !            65:        int     (*userauth)(Authctxt *authctxt);
        !            66:        int     *enabled;
        !            67: };
        !            68:
1.1       markus     69: /* protocol */
                     70:
1.8.2.2 ! jason      71: void   input_service_request(int type, int plen, void *ctxt);
        !            72: void   input_userauth_request(int type, int plen, void *ctxt);
        !            73: void   protocol_error(int type, int plen, void *ctxt);
1.1       markus     74:
                     75:
                     76: /* helper */
1.8.2.2 ! jason      77: Authmethod     *authmethod_lookup(const char *name);
        !            78: struct passwd  *pwcopy(struct passwd *pw);
1.1       markus     79: int    user_dsa_key_allowed(struct passwd *pw, Key *key);
1.8.2.2 ! jason      80: char   *authmethods_get(void);
1.1       markus     81:
1.8.2.2 ! jason      82: /* auth */
        !            83: int    userauth_none(Authctxt *authctxt);
        !            84: int    userauth_passwd(Authctxt *authctxt);
        !            85: int    userauth_pubkey(Authctxt *authctxt);
        !            86: int    userauth_kbdint(Authctxt *authctxt);
        !            87:
        !            88: Authmethod authmethods[] = {
        !            89:        {"none",
        !            90:                userauth_none,
        !            91:                &one},
        !            92:        {"publickey",
        !            93:                userauth_pubkey,
        !            94:                &options.dsa_authentication},
        !            95:        {"keyboard-interactive",
        !            96:                userauth_kbdint,
        !            97:                &options.kbd_interactive_authentication},
        !            98:        {"password",
        !            99:                userauth_passwd,
        !           100:                &options.password_authentication},
        !           101:        {NULL, NULL, NULL}
1.1       markus    102: };
                    103:
                    104: /*
1.8.2.2 ! jason     105:  * loop until authctxt->success == TRUE
1.1       markus    106:  */
                    107:
                    108: void
                    109: do_authentication2()
                    110: {
1.8.2.2 ! jason     111:        Authctxt *authctxt = xmalloc(sizeof(*authctxt));
        !           112:        memset(authctxt, 'a', sizeof(*authctxt));
        !           113:        authctxt->valid = 0;
        !           114:        authctxt->attempt = 0;
        !           115:        authctxt->success = 0;
        !           116:        x_authctxt = authctxt;          /*XXX*/
        !           117:
1.5       djm       118: #ifdef KRB4
1.8.2.2 ! jason     119:        /* turn off kerberos, not supported by SSH2 */
1.4       markus    120:        options.kerberos_authentication = 0;
1.5       djm       121: #endif
1.1       markus    122:        dispatch_init(&protocol_error);
                    123:        dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request);
1.8.2.2 ! jason     124:        dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt);
1.1       markus    125:        do_authenticated2();
                    126: }
                    127:
                    128: void
1.8.2.2 ! jason     129: protocol_error(int type, int plen, void *ctxt)
1.1       markus    130: {
                    131:        log("auth: protocol error: type %d plen %d", type, plen);
                    132:        packet_start(SSH2_MSG_UNIMPLEMENTED);
                    133:        packet_put_int(0);
                    134:        packet_send();
                    135:        packet_write_wait();
                    136: }
                    137:
                    138: void
1.8.2.2 ! jason     139: input_service_request(int type, int plen, void *ctxt)
1.1       markus    140: {
1.8.2.2 ! jason     141:        Authctxt *authctxt = ctxt;
1.1       markus    142:        unsigned int len;
                    143:        int accept = 0;
                    144:        char *service = packet_get_string(&len);
                    145:        packet_done();
                    146:
1.8.2.2 ! jason     147:        if (authctxt == NULL)
        !           148:                fatal("input_service_request: no authctxt");
        !           149:
1.1       markus    150:        if (strcmp(service, "ssh-userauth") == 0) {
1.8.2.2 ! jason     151:                if (!authctxt->success) {
1.1       markus    152:                        accept = 1;
                    153:                        /* now we can handle user-auth requests */
                    154:                        dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request);
                    155:                }
                    156:        }
                    157:        /* XXX all other service requests are denied */
                    158:
                    159:        if (accept) {
                    160:                packet_start(SSH2_MSG_SERVICE_ACCEPT);
                    161:                packet_put_cstring(service);
                    162:                packet_send();
                    163:                packet_write_wait();
                    164:        } else {
                    165:                debug("bad service request %s", service);
                    166:                packet_disconnect("bad service request %s", service);
                    167:        }
                    168:        xfree(service);
                    169: }
                    170:
                    171: void
1.8.2.2 ! jason     172: input_userauth_request(int type, int plen, void *ctxt)
1.1       markus    173: {
1.8.2.2 ! jason     174:        Authctxt *authctxt = ctxt;
        !           175:        Authmethod *m = NULL;
        !           176:        char *user, *service, *method;
1.1       markus    177:        int authenticated = 0;
                    178:
1.8.2.2 ! jason     179:        if (authctxt == NULL)
        !           180:                fatal("input_userauth_request: no authctxt");
        !           181:        if (authctxt->attempt++ >= AUTH_FAIL_MAX)
1.1       markus    182:                packet_disconnect("too many failed userauth_requests");
                    183:
1.8.2.2 ! jason     184:        user = packet_get_string(NULL);
        !           185:        service = packet_get_string(NULL);
        !           186:        method = packet_get_string(NULL);
1.1       markus    187:        debug("userauth-request for user %s service %s method %s", user, service, method);
1.8.2.2 ! jason     188:        debug("attempt #%d", authctxt->attempt);
1.1       markus    189:
1.8.2.2 ! jason     190:        if (authctxt->attempt == 1) {
        !           191:                /* setup auth context */
        !           192:                struct passwd *pw = NULL;
        !           193:                setproctitle("%s", user);
        !           194:                pw = getpwnam(user);
        !           195:                if (pw && allowed_user(pw) && strcmp(service, "ssh-connection")==0) {
        !           196:                        authctxt->pw = pwcopy(pw);
        !           197:                        authctxt->valid = 1;
        !           198:                        debug2("input_userauth_request: setting up authctxt for %s", user);
        !           199:                } else {
        !           200:                        log("input_userauth_request: illegal user %s", user);
1.1       markus    201:                }
1.8.2.2 ! jason     202:                authctxt->user = xstrdup(user);
        !           203:                authctxt->service = xstrdup(service);
        !           204:        } else if (authctxt->valid) {
        !           205:                if (strcmp(user, authctxt->user) != 0 ||
        !           206:                    strcmp(service, authctxt->service) != 0) {
        !           207:                        log("input_userauth_request: missmatch: (%s,%s)!=(%s,%s)",
        !           208:                            user, service, authctxt->user, authctxt->service);
        !           209:                        authctxt->valid = 0;
        !           210:                }
        !           211:        }
        !           212:
        !           213:        m = authmethod_lookup(method);
        !           214:        if (m != NULL) {
        !           215:                debug2("input_userauth_request: try method %s", method);
        !           216:                authenticated = m->userauth(authctxt);
        !           217:        } else {
        !           218:                debug2("input_userauth_request: unsupported method %s", method);
1.1       markus    219:        }
1.8.2.2 ! jason     220:        if (!authctxt->valid && authenticated == 1) {
        !           221:                log("input_userauth_request: INTERNAL ERROR: authenticated invalid user %s service %s", user, method);
        !           222:                authenticated = 0;
        !           223:        }
        !           224:
        !           225:        /* Special handling for root */
        !           226:        if (authenticated == 1 &&
        !           227:            authctxt->valid && authctxt->pw->pw_uid == 0 && !options.permit_root_login) {
1.3       markus    228:                authenticated = 0;
1.8.2.2 ! jason     229:                log("ROOT LOGIN REFUSED FROM %.200s", get_canonical_hostname());
1.3       markus    230:        }
                    231:
1.8.2.2 ! jason     232:        /* Log before sending the reply */
        !           233:        userauth_log(authctxt, authenticated, method);
        !           234:        userauth_reply(authctxt, authenticated);
        !           235:
        !           236:        xfree(service);
        !           237:        xfree(user);
        !           238:        xfree(method);
        !           239: }
        !           240:
        !           241:
        !           242: void
        !           243: userauth_log(Authctxt *authctxt, int authenticated, char *method)
        !           244: {
        !           245:        void (*authlog) (const char *fmt,...) = verbose;
        !           246:        char *user = NULL, *authmsg = NULL;
        !           247:
1.6       markus    248:        /* Raise logging level */
                    249:        if (authenticated == 1 ||
1.8.2.2 ! jason     250:            !authctxt->valid ||
        !           251:            authctxt->attempt >= AUTH_FAIL_LOG ||
1.6       markus    252:            strcmp(method, "password") == 0)
                    253:                authlog = log;
                    254:
                    255:        if (authenticated == 1) {
                    256:                authmsg = "Accepted";
                    257:        } else if (authenticated == 0) {
                    258:                authmsg = "Failed";
                    259:        } else {
                    260:                authmsg = "Postponed";
                    261:        }
1.8.2.2 ! jason     262:
        !           263:        if (authctxt->valid) {
        !           264:                user = authctxt->pw->pw_uid == 0 ? "ROOT" : authctxt->user;
        !           265:        } else {
        !           266:                user = "NOUSER";
        !           267:        }
        !           268:
1.6       markus    269:        authlog("%s %s for %.200s from %.200s port %d ssh2",
1.8.2.2 ! jason     270:            authmsg,
        !           271:            method,
        !           272:            user,
        !           273:            get_remote_ipaddr(),
        !           274:            get_remote_port());
        !           275: }
1.6       markus    276:
1.8.2.2 ! jason     277: void
        !           278: userauth_reply(Authctxt *authctxt, int authenticated)
        !           279: {
1.3       markus    280:        /* XXX todo: check if multiple auth methods are needed */
1.1       markus    281:        if (authenticated == 1) {
                    282:                /* turn off userauth */
                    283:                dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &protocol_error);
                    284:                packet_start(SSH2_MSG_USERAUTH_SUCCESS);
                    285:                packet_send();
                    286:                packet_write_wait();
                    287:                /* now we can break out */
1.8.2.2 ! jason     288:                authctxt->success = 1;
1.1       markus    289:        } else if (authenticated == 0) {
1.8.2.2 ! jason     290:                char *methods = authmethods_get();
1.1       markus    291:                packet_start(SSH2_MSG_USERAUTH_FAILURE);
1.8.2.2 ! jason     292:                packet_put_cstring(methods);
        !           293:                packet_put_char(0);     /* XXX partial success, unused */
1.1       markus    294:                packet_send();
                    295:                packet_write_wait();
1.8.2.2 ! jason     296:                xfree(methods);
        !           297:        } else {
        !           298:                /* do nothing, we did already send a reply */
1.1       markus    299:        }
                    300: }
                    301:
                    302: int
1.8.2.2 ! jason     303: userauth_none(Authctxt *authctxt)
1.1       markus    304: {
1.8.2.2 ! jason     305:        /* disable method "none", only allowed one time */
        !           306:        Authmethod *m = authmethod_lookup("none");
        !           307:        if (m != NULL)
        !           308:                m->enabled = NULL;
1.1       markus    309:        packet_done();
1.8.2.2 ! jason     310:        return authctxt->valid ? auth_password(authctxt->pw, "") : 0;
1.1       markus    311: }
1.8.2.2 ! jason     312:
1.1       markus    313: int
1.8.2.2 ! jason     314: userauth_passwd(Authctxt *authctxt)
1.1       markus    315: {
                    316:        char *password;
                    317:        int authenticated = 0;
                    318:        int change;
                    319:        unsigned int len;
                    320:        change = packet_get_char();
                    321:        if (change)
                    322:                log("password change not supported");
                    323:        password = packet_get_string(&len);
                    324:        packet_done();
1.8.2.2 ! jason     325:        if (authctxt->valid &&
        !           326:            auth_password(authctxt->pw, password) == 1)
1.1       markus    327:                authenticated = 1;
                    328:        memset(password, 0, len);
                    329:        xfree(password);
                    330:        return authenticated;
                    331: }
1.8.2.2 ! jason     332:
        !           333: int
        !           334: userauth_kbdint(Authctxt *authctxt)
        !           335: {
        !           336:        int authenticated = 0;
        !           337:        char *lang = NULL;
        !           338:        char *devs = NULL;
        !           339:
        !           340:        lang = packet_get_string(NULL);
        !           341:        devs = packet_get_string(NULL);
        !           342:        packet_done();
        !           343:
        !           344:        debug("keyboard-interactive language %s devs %s", lang, devs);
        !           345: #ifdef SKEY
        !           346:        /* XXX hardcoded, we should look at devs */
        !           347:        if (options.skey_authentication != 0)
        !           348:                authenticated = auth2_skey(authctxt);
        !           349: #endif
        !           350:        xfree(lang);
        !           351:        xfree(devs);
        !           352:        return authenticated;
        !           353: }
        !           354:
1.1       markus    355: int
1.8.2.2 ! jason     356: userauth_pubkey(Authctxt *authctxt)
1.1       markus    357: {
                    358:        Buffer b;
                    359:        Key *key;
                    360:        char *pkalg, *pkblob, *sig;
                    361:        unsigned int alen, blen, slen;
                    362:        int have_sig;
                    363:        int authenticated = 0;
                    364:
1.8.2.2 ! jason     365:        if (!authctxt->valid) {
        !           366:                debug2("userauth_pubkey: disabled because of invalid user");
1.8       markus    367:                return 0;
                    368:        }
1.1       markus    369:        have_sig = packet_get_char();
                    370:        pkalg = packet_get_string(&alen);
                    371:        if (strcmp(pkalg, KEX_DSS) != 0) {
                    372:                log("bad pkalg %s", pkalg);     /*XXX*/
1.8.2.2 ! jason     373:                xfree(pkalg);
1.1       markus    374:                return 0;
                    375:        }
                    376:        pkblob = packet_get_string(&blen);
                    377:        key = dsa_key_from_blob(pkblob, blen);
1.2       markus    378:        if (key != NULL) {
                    379:                if (have_sig) {
                    380:                        sig = packet_get_string(&slen);
                    381:                        packet_done();
                    382:                        buffer_init(&b);
1.8.2.2 ! jason     383:                        if (datafellows & SSH_OLD_SESSIONID) {
1.8.2.1   jason     384:                                buffer_append(&b, session_id2, session_id2_len);
1.8.2.2 ! jason     385:                        } else {
        !           386:                                buffer_put_string(&b, session_id2, session_id2_len);
1.8.2.1   jason     387:                        }
                    388:                        /* reconstruct packet */
1.2       markus    389:                        buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.8.2.2 ! jason     390:                        buffer_put_cstring(&b, authctxt->user);
1.8.2.1   jason     391:                        buffer_put_cstring(&b,
                    392:                            datafellows & SSH_BUG_PUBKEYAUTH ?
                    393:                            "ssh-userauth" :
1.8.2.2 ! jason     394:                            authctxt->service);
1.8.2.1   jason     395:                        buffer_put_cstring(&b, "publickey");
                    396:                        buffer_put_char(&b, have_sig);
                    397:                        buffer_put_cstring(&b, KEX_DSS);
                    398:                        buffer_put_string(&b, pkblob, blen);
1.1       markus    399: #ifdef DEBUG_DSS
1.2       markus    400:                        buffer_dump(&b);
1.1       markus    401: #endif
1.2       markus    402:                        /* test for correct signature */
1.8.2.2 ! jason     403:                        if (user_dsa_key_allowed(authctxt->pw, key) &&
1.2       markus    404:                            dsa_verify(key, sig, slen, buffer_ptr(&b), buffer_len(&b)) == 1)
                    405:                                authenticated = 1;
                    406:                        buffer_clear(&b);
                    407:                        xfree(sig);
                    408:                } else {
1.8.2.2 ! jason     409:                        debug("test whether pkalg/pkblob are acceptable");
1.2       markus    410:                        packet_done();
1.8.2.2 ! jason     411:
1.2       markus    412:                        /* XXX fake reply and always send PK_OK ? */
1.6       markus    413:                        /*
                    414:                         * XXX this allows testing whether a user is allowed
                    415:                         * to login: if you happen to have a valid pubkey this
                    416:                         * message is sent. the message is NEVER sent at all
                    417:                         * if a user is not allowed to login. is this an
                    418:                         * issue? -markus
                    419:                         */
1.8.2.2 ! jason     420:                        if (user_dsa_key_allowed(authctxt->pw, key)) {
1.2       markus    421:                                packet_start(SSH2_MSG_USERAUTH_PK_OK);
                    422:                                packet_put_string(pkalg, alen);
                    423:                                packet_put_string(pkblob, blen);
                    424:                                packet_send();
                    425:                                packet_write_wait();
                    426:                                authenticated = -1;
                    427:                        }
1.1       markus    428:                }
1.8.2.2 ! jason     429:                if (authenticated != 1)
        !           430:                        auth_clear_options();
1.2       markus    431:                key_free(key);
1.1       markus    432:        }
                    433:        xfree(pkalg);
                    434:        xfree(pkblob);
                    435:        return authenticated;
                    436: }
                    437:
1.8.2.2 ! jason     438: /* get current user */
1.1       markus    439:
                    440: struct passwd*
                    441: auth_get_user(void)
                    442: {
1.8.2.2 ! jason     443:        return (x_authctxt != NULL && x_authctxt->valid) ? x_authctxt->pw : NULL;
1.1       markus    444: }
                    445:
1.8.2.2 ! jason     446: #define        DELIM   ","
        !           447:
        !           448: char *
        !           449: authmethods_get(void)
1.1       markus    450: {
1.8.2.2 ! jason     451:        Authmethod *method = NULL;
        !           452:        unsigned int size = 0;
        !           453:        char *list;
1.1       markus    454:
1.8.2.2 ! jason     455:        for (method = authmethods; method->name != NULL; method++) {
        !           456:                if (strcmp(method->name, "none") == 0)
        !           457:                        continue;
        !           458:                if (method->enabled != NULL && *(method->enabled) != 0) {
        !           459:                        if (size != 0)
        !           460:                                size += strlen(DELIM);
        !           461:                        size += strlen(method->name);
1.1       markus    462:                }
1.8.2.2 ! jason     463:        }
        !           464:        size++;                 /* trailing '\0' */
        !           465:        list = xmalloc(size);
        !           466:        list[0] = '\0';
        !           467:
        !           468:        for (method = authmethods; method->name != NULL; method++) {
        !           469:                if (strcmp(method->name, "none") == 0)
        !           470:                        continue;
        !           471:                if (method->enabled != NULL && *(method->enabled) != 0) {
        !           472:                        if (list[0] != '\0')
        !           473:                                strlcat(list, DELIM, size);
        !           474:                        strlcat(list, method->name, size);
1.1       markus    475:                }
                    476:        }
1.8.2.2 ! jason     477:        return list;
        !           478: }
        !           479:
        !           480: Authmethod *
        !           481: authmethod_lookup(const char *name)
        !           482: {
        !           483:        Authmethod *method = NULL;
        !           484:        if (name != NULL)
        !           485:                for (method = authmethods; method->name != NULL; method++)
        !           486:                        if (method->enabled != NULL &&
        !           487:                            *(method->enabled) != 0 &&
        !           488:                            strcmp(name, method->name) == 0)
        !           489:                                return method;
        !           490:        debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
        !           491:        return NULL;
1.1       markus    492: }
                    493:
                    494: /* return 1 if user allows given key */
                    495: int
                    496: user_dsa_key_allowed(struct passwd *pw, Key *key)
                    497: {
                    498:        char line[8192], file[1024];
                    499:        int found_key = 0;
                    500:        unsigned int bits = -1;
                    501:        FILE *f;
                    502:        unsigned long linenum = 0;
                    503:        struct stat st;
                    504:        Key *found;
                    505:
1.8.2.2 ! jason     506:        if (pw == NULL)
        !           507:                return 0;
        !           508:
1.1       markus    509:        /* Temporarily use the user's uid. */
                    510:        temporarily_use_uid(pw->pw_uid);
                    511:
                    512:        /* The authorized keys. */
                    513:        snprintf(file, sizeof file, "%.500s/%.100s", pw->pw_dir,
                    514:            SSH_USER_PERMITTED_KEYS2);
                    515:
                    516:        /* Fail quietly if file does not exist */
                    517:        if (stat(file, &st) < 0) {
                    518:                /* Restore the privileged uid. */
                    519:                restore_uid();
                    520:                return 0;
                    521:        }
                    522:        /* Open the file containing the authorized keys. */
                    523:        f = fopen(file, "r");
                    524:        if (!f) {
                    525:                /* Restore the privileged uid. */
                    526:                restore_uid();
                    527:                return 0;
                    528:        }
                    529:        if (options.strict_modes) {
                    530:                int fail = 0;
                    531:                char buf[1024];
                    532:                /* Check open file in order to avoid open/stat races */
                    533:                if (fstat(fileno(f), &st) < 0 ||
                    534:                    (st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
                    535:                    (st.st_mode & 022) != 0) {
1.8.2.2 ! jason     536:                        snprintf(buf, sizeof buf,
        !           537:                            "%s authentication refused for %.100s: "
        !           538:                            "bad ownership or modes for '%s'.",
        !           539:                            key_type(key), pw->pw_name, file);
1.1       markus    540:                        fail = 1;
                    541:                } else {
                    542:                        /* Check path to SSH_USER_PERMITTED_KEYS */
                    543:                        int i;
                    544:                        static const char *check[] = {
                    545:                                "", SSH_USER_DIR, NULL
                    546:                        };
                    547:                        for (i = 0; check[i]; i++) {
                    548:                                snprintf(line, sizeof line, "%.500s/%.100s",
                    549:                                    pw->pw_dir, check[i]);
                    550:                                if (stat(line, &st) < 0 ||
                    551:                                    (st.st_uid != 0 && st.st_uid != pw->pw_uid) ||
                    552:                                    (st.st_mode & 022) != 0) {
                    553:                                        snprintf(buf, sizeof buf,
1.8.2.2 ! jason     554:                                            "%s authentication refused for %.100s: "
1.1       markus    555:                                            "bad ownership or modes for '%s'.",
1.8.2.2 ! jason     556:                                            key_type(key), pw->pw_name, line);
1.1       markus    557:                                        fail = 1;
                    558:                                        break;
                    559:                                }
                    560:                        }
                    561:                }
                    562:                if (fail) {
                    563:                        fclose(f);
1.8.2.1   jason     564:                        log("%s",buf);
1.1       markus    565:                        restore_uid();
                    566:                        return 0;
                    567:                }
                    568:        }
                    569:        found_key = 0;
1.8.2.2 ! jason     570:        found = key_new(key->type);
1.1       markus    571:
                    572:        while (fgets(line, sizeof(line), f)) {
1.8.2.1   jason     573:                char *cp, *options = NULL;
1.1       markus    574:                linenum++;
                    575:                /* Skip leading whitespace, empty and comment lines. */
                    576:                for (cp = line; *cp == ' ' || *cp == '\t'; cp++)
                    577:                        ;
                    578:                if (!*cp || *cp == '\n' || *cp == '#')
                    579:                        continue;
1.8.2.1   jason     580:
1.1       markus    581:                bits = key_read(found, &cp);
1.8.2.1   jason     582:                if (bits == 0) {
                    583:                        /* no key?  check if there are options for this key */
                    584:                        int quoted = 0;
                    585:                        options = cp;
                    586:                        for (; *cp && (quoted || (*cp != ' ' && *cp != '\t')); cp++) {
                    587:                                if (*cp == '\\' && cp[1] == '"')
                    588:                                        cp++;   /* Skip both */
                    589:                                else if (*cp == '"')
                    590:                                        quoted = !quoted;
                    591:                        }
                    592:                        /* Skip remaining whitespace. */
                    593:                        for (; *cp == ' ' || *cp == '\t'; cp++)
                    594:                                ;
                    595:                        bits = key_read(found, &cp);
                    596:                        if (bits == 0) {
                    597:                                /* still no key?  advance to next line*/
                    598:                                continue;
                    599:                        }
                    600:                }
                    601:                if (key_equal(found, key) &&
                    602:                    auth_parse_options(pw, options, linenum) == 1) {
1.1       markus    603:                        found_key = 1;
                    604:                        debug("matching key found: file %s, line %ld",
                    605:                            file, linenum);
                    606:                        break;
                    607:                }
                    608:        }
                    609:        restore_uid();
                    610:        fclose(f);
                    611:        key_free(found);
                    612:        return found_key;
1.8.2.2 ! jason     613: }
        !           614:
        !           615: struct passwd *
        !           616: pwcopy(struct passwd *pw)
        !           617: {
        !           618:        struct passwd *copy = xmalloc(sizeof(*copy));
        !           619:        memset(copy, 0, sizeof(*copy));
        !           620:        copy->pw_name = xstrdup(pw->pw_name);
        !           621:        copy->pw_passwd = xstrdup(pw->pw_passwd);
        !           622:        copy->pw_uid = pw->pw_uid;
        !           623:        copy->pw_gid = pw->pw_gid;
        !           624:        copy->pw_class = xstrdup(pw->pw_class);
        !           625:        copy->pw_dir = xstrdup(pw->pw_dir);
        !           626:        copy->pw_shell = xstrdup(pw->pw_shell);
        !           627:        return copy;
1.1       markus    628: }