*/
#include "includes.h"
-RCSID("$OpenBSD: auth2.c,v 1.73 2001/11/17 19:14:34 stevesk Exp $");
+RCSID("$OpenBSD: auth2.c,v 1.91 2002/05/13 02:37:39 itojun Exp $");
#include <openssl/evp.h>
#include "pathnames.h"
#include "uidswap.h"
#include "auth-options.h"
-#include "misc.h"
#include "hostfile.h"
#include "canohost.h"
#include "match.h"
+#include "monitor_wrap.h"
+#include "atomicio.h"
/* import */
extern ServerOptions options;
extern u_char *session_id2;
extern int session_id2_len;
-static Authctxt *x_authctxt = NULL;
+Authctxt *x_authctxt = NULL;
static int one = 1;
typedef struct Authmethod Authmethod;
/* protocol */
-static void input_service_request(int, int, void *);
-static void input_userauth_request(int, int, void *);
-static void protocol_error(int, int, void *);
+static void input_service_request(int, u_int32_t, void *);
+static void input_userauth_request(int, u_int32_t, void *);
/* helper */
static Authmethod *authmethod_lookup(const char *);
static char *authmethods_get(void);
-static int user_key_allowed(struct passwd *, Key *);
-static int hostbased_key_allowed(struct passwd *, const char *, char *, Key *);
+int user_key_allowed(struct passwd *, Key *);
+int hostbased_key_allowed(struct passwd *, const char *, char *, Key *);
/* auth */
static void userauth_banner(void);
* loop until authctxt->success == TRUE
*/
-void
-do_authentication2()
+Authctxt *
+do_authentication2(void)
{
Authctxt *authctxt = authctxt_new();
options.kbd_interactive_authentication = 1;
if (options.pam_authentication_via_kbd_int)
options.kbd_interactive_authentication = 1;
+ if (use_privsep)
+ options.pam_authentication_via_kbd_int = 0;
- dispatch_init(&protocol_error);
+ dispatch_init(&dispatch_protocol_error);
dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request);
dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt);
- do_authenticated(authctxt);
-}
-static void
-protocol_error(int type, int plen, void *ctxt)
-{
- log("auth: protocol error: type %d plen %d", type, plen);
- packet_start(SSH2_MSG_UNIMPLEMENTED);
- packet_put_int(0);
- packet_send();
- packet_write_wait();
+ return (authctxt);
}
static void
-input_service_request(int type, int plen, void *ctxt)
+input_service_request(int type, u_int32_t seq, void *ctxt)
{
Authctxt *authctxt = ctxt;
u_int len;
int accept = 0;
char *service = packet_get_string(&len);
- packet_done();
+ packet_check_eom();
if (authctxt == NULL)
fatal("input_service_request: no authctxt");
}
static void
-input_userauth_request(int type, int plen, void *ctxt)
+input_userauth_request(int type, u_int32_t seq, void *ctxt)
{
Authctxt *authctxt = ctxt;
Authmethod *m = NULL;
if (authctxt->attempt++ == 0) {
/* setup auth context */
- struct passwd *pw = NULL;
- pw = getpwnam(user);
- if (pw && allowed_user(pw) && strcmp(service, "ssh-connection")==0) {
- authctxt->pw = pwcopy(pw);
+ authctxt->pw = PRIVSEP(getpwnamallow(user));
+ if (authctxt->pw && strcmp(service, "ssh-connection")==0) {
authctxt->valid = 1;
debug2("input_userauth_request: setting up authctxt for %s", user);
#ifdef USE_PAM
- start_pam(pw->pw_name);
+ PRIVSEP(start_pam(authctxt->pw->pw_name));
#endif
} else {
log("input_userauth_request: illegal user %s", user);
#ifdef USE_PAM
- start_pam("NOUSER");
+ PRIVSEP(start_pam("NOUSER"));
#endif
}
- setproctitle("%s", pw ? user : "unknown");
+ setproctitle("%s%s", authctxt->pw ? user : "unknown",
+ use_privsep ? " [net]" : "");
authctxt->user = xstrdup(user);
authctxt->service = xstrdup(service);
authctxt->style = style ? xstrdup(style) : NULL;
+ if (use_privsep)
+ mm_inform_authserv(service, style);
} else if (strcmp(user, authctxt->user) != 0 ||
strcmp(service, authctxt->service) != 0) {
packet_disconnect("Change of username or service not allowed: "
authctxt->user, authctxt->service, user, service);
}
/* reset state */
- dispatch_set(SSH2_MSG_USERAUTH_INFO_RESPONSE, &protocol_error);
+ auth2_challenge_stop(authctxt);
authctxt->postponed = 0;
-#ifdef BSD_AUTH
- if (authctxt->as) {
- auth_close(authctxt->as);
- authctxt->as = NULL;
- }
-#endif
/* try to authenticate user */
m = authmethod_lookup(method);
authenticated = 0;
#ifdef USE_PAM
- if (authenticated && authctxt->user && !do_pam_account(authctxt->user,
- NULL))
+ if (!use_privsep && authenticated && authctxt->user &&
+ !do_pam_account(authctxt->user, NULL))
authenticated = 0;
#endif /* USE_PAM */
/* XXX todo: check if multiple auth methods are needed */
if (authenticated == 1) {
/* turn off userauth */
- dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &protocol_error);
+ dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore);
packet_start(SSH2_MSG_USERAUTH_SUCCESS);
packet_send();
packet_write_wait();
if (authctxt->failures++ > AUTH_FAIL_MAX) {
#ifdef WITH_AIXAUTHENTICATE
loginfailed(authctxt->user,
- get_canonical_hostname(options.reverse_mapping_check),
+ get_canonical_hostname(options.verify_reverse_mapping),
"ssh");
#endif /* WITH_AIXAUTHENTICATE */
packet_disconnect(AUTH_FAIL_MSG, authctxt->user);
}
}
-static void
-userauth_banner(void)
+char *
+auth2_read_banner(void)
{
struct stat st;
char *banner = NULL;
off_t len, n;
int fd;
- if (options.banner == NULL || (datafellows & SSH_BUG_BANNER))
- return;
- if ((fd = open(options.banner, O_RDONLY)) < 0)
- return;
- if (fstat(fd, &st) < 0)
- goto done;
+ if ((fd = open(options.banner, O_RDONLY)) == -1)
+ return (NULL);
+ if (fstat(fd, &st) == -1) {
+ close(fd);
+ return (NULL);
+ }
len = st.st_size;
banner = xmalloc(len + 1);
- if ((n = read(fd, banner, len)) < 0)
- goto done;
+ n = atomicio(read, fd, banner, len);
+ close(fd);
+
+ if (n != len) {
+ free(banner);
+ return (NULL);
+ }
banner[n] = '\0';
+
+ return (banner);
+}
+
+static void
+userauth_banner(void)
+{
+ char *banner = NULL;
+
+ if (options.banner == NULL || (datafellows & SSH_BUG_BANNER))
+ return;
+
+ if ((banner = PRIVSEP(auth2_read_banner())) == NULL)
+ goto done;
+
packet_start(SSH2_MSG_USERAUTH_BANNER);
packet_put_cstring(banner);
packet_put_cstring(""); /* language, unused */
done:
if (banner)
xfree(banner);
- close(fd);
return;
}
Authmethod *m = authmethod_lookup("none");
if (m != NULL)
m->enabled = NULL;
- packet_done();
+ packet_check_eom();
userauth_banner();
if (authctxt->valid == 0)
return(0);
#ifdef HAVE_CYGWIN
- if (check_nt_auth(1, authctxt->pw->pw_uid) == 0)
+ if (check_nt_auth(1, authctxt->pw) == 0)
return(0);
#endif
-#ifdef USE_PAM
- return auth_pam_password(authctxt->pw, "");
-#elif defined(HAVE_OSF_SIA)
- return 0;
-#else /* !HAVE_OSF_SIA && !USE_PAM */
- return auth_password(authctxt, "");
-#endif /* USE_PAM */
+ return PRIVSEP(auth_password(authctxt, ""));
}
static int
if (change)
log("password change not supported");
password = packet_get_string(&len);
- packet_done();
+ packet_check_eom();
if (authctxt->valid &&
#ifdef HAVE_CYGWIN
- check_nt_auth(1, authctxt->pw->pw_uid) &&
+ check_nt_auth(1, authctxt->pw) &&
#endif
-#ifdef USE_PAM
- auth_pam_password(authctxt->pw, password) == 1)
-#elif defined(HAVE_OSF_SIA)
- auth_sia_password(authctxt->user, password) == 1)
-#else /* !USE_PAM && !HAVE_OSF_SIA */
- auth_password(authctxt, password) == 1)
-#endif /* USE_PAM */
+ PRIVSEP(auth_password(authctxt, password)) == 1)
authenticated = 1;
memset(password, 0, len);
xfree(password);
lang = packet_get_string(NULL);
devs = packet_get_string(NULL);
- packet_done();
+ packet_check_eom();
debug("keyboard-interactive devs %s", devs);
xfree(devs);
xfree(lang);
#ifdef HAVE_CYGWIN
- if (check_nt_auth(0, authctxt->pw->pw_uid) == 0)
+ if (check_nt_auth(0, authctxt->pw) == 0)
return(0);
#endif
return authenticated;
userauth_pubkey(Authctxt *authctxt)
{
Buffer b;
- Key *key;
- char *pkalg, *pkblob, *sig;
+ Key *key = NULL;
+ char *pkalg;
+ u_char *pkblob, *sig;
u_int alen, blen, slen;
int have_sig, pktype;
int authenticated = 0;
pktype = key_type_from_name(pkalg);
if (pktype == KEY_UNSPEC) {
/* this is perfectly legal */
- log("userauth_pubkey: unsupported public key algorithm: %s", pkalg);
- xfree(pkalg);
- xfree(pkblob);
- return 0;
+ log("userauth_pubkey: unsupported public key algorithm: %s",
+ pkalg);
+ goto done;
}
key = key_from_blob(pkblob, blen);
- if (key != NULL) {
- if (have_sig) {
- sig = packet_get_string(&slen);
- packet_done();
- buffer_init(&b);
- if (datafellows & SSH_OLD_SESSIONID) {
- buffer_append(&b, session_id2, session_id2_len);
- } else {
- buffer_put_string(&b, session_id2, session_id2_len);
- }
- /* reconstruct packet */
- buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
- buffer_put_cstring(&b, authctxt->user);
- buffer_put_cstring(&b,
- datafellows & SSH_BUG_PKSERVICE ?
- "ssh-userauth" :
- authctxt->service);
- if (datafellows & SSH_BUG_PKAUTH) {
- buffer_put_char(&b, have_sig);
- } else {
- buffer_put_cstring(&b, "publickey");
- buffer_put_char(&b, have_sig);
- buffer_put_cstring(&b, pkalg);
- }
- buffer_put_string(&b, pkblob, blen);
+ if (key == NULL) {
+ error("userauth_pubkey: cannot decode key: %s", pkalg);
+ goto done;
+ }
+ if (key->type != pktype) {
+ error("userauth_pubkey: type mismatch for decoded key "
+ "(received %d, expected %d)", key->type, pktype);
+ goto done;
+ }
+ if (have_sig) {
+ sig = packet_get_string(&slen);
+ packet_check_eom();
+ buffer_init(&b);
+ if (datafellows & SSH_OLD_SESSIONID) {
+ buffer_append(&b, session_id2, session_id2_len);
+ } else {
+ buffer_put_string(&b, session_id2, session_id2_len);
+ }
+ /* reconstruct packet */
+ buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
+ buffer_put_cstring(&b, authctxt->user);
+ buffer_put_cstring(&b,
+ datafellows & SSH_BUG_PKSERVICE ?
+ "ssh-userauth" :
+ authctxt->service);
+ if (datafellows & SSH_BUG_PKAUTH) {
+ buffer_put_char(&b, have_sig);
+ } else {
+ buffer_put_cstring(&b, "publickey");
+ buffer_put_char(&b, have_sig);
+ buffer_put_cstring(&b, pkalg);
+ }
+ buffer_put_string(&b, pkblob, blen);
#ifdef DEBUG_PK
- buffer_dump(&b);
+ buffer_dump(&b);
#endif
- /* test for correct signature */
- if (user_key_allowed(authctxt->pw, key) &&
- key_verify(key, sig, slen, buffer_ptr(&b), buffer_len(&b)) == 1)
- authenticated = 1;
- buffer_clear(&b);
- xfree(sig);
- } else {
- debug("test whether pkalg/pkblob are acceptable");
- packet_done();
-
- /* XXX fake reply and always send PK_OK ? */
- /*
- * XXX this allows testing whether a user is allowed
- * to login: if you happen to have a valid pubkey this
- * message is sent. the message is NEVER sent at all
- * if a user is not allowed to login. is this an
- * issue? -markus
- */
- if (user_key_allowed(authctxt->pw, key)) {
- packet_start(SSH2_MSG_USERAUTH_PK_OK);
- packet_put_string(pkalg, alen);
- packet_put_string(pkblob, blen);
- packet_send();
- packet_write_wait();
- authctxt->postponed = 1;
- }
+ /* test for correct signature */
+ authenticated = 0;
+ if (PRIVSEP(user_key_allowed(authctxt->pw, key)) &&
+ PRIVSEP(key_verify(key, sig, slen, buffer_ptr(&b),
+ buffer_len(&b))) == 1)
+ authenticated = 1;
+ buffer_clear(&b);
+ xfree(sig);
+ } else {
+ debug("test whether pkalg/pkblob are acceptable");
+ packet_check_eom();
+
+ /* XXX fake reply and always send PK_OK ? */
+ /*
+ * XXX this allows testing whether a user is allowed
+ * to login: if you happen to have a valid pubkey this
+ * message is sent. the message is NEVER sent at all
+ * if a user is not allowed to login. is this an
+ * issue? -markus
+ */
+ if (PRIVSEP(user_key_allowed(authctxt->pw, key))) {
+ packet_start(SSH2_MSG_USERAUTH_PK_OK);
+ packet_put_string(pkalg, alen);
+ packet_put_string(pkblob, blen);
+ packet_send();
+ packet_write_wait();
+ authctxt->postponed = 1;
}
- if (authenticated != 1)
- auth_clear_options();
- key_free(key);
}
+ if (authenticated != 1)
+ auth_clear_options();
+done:
debug2("userauth_pubkey: authenticated %d pkalg %s", authenticated, pkalg);
+ if (key != NULL)
+ key_free(key);
xfree(pkalg);
xfree(pkblob);
#ifdef HAVE_CYGWIN
- if (check_nt_auth(0, authctxt->pw->pw_uid) == 0)
+ if (check_nt_auth(0, authctxt->pw) == 0)
return(0);
#endif
return authenticated;
userauth_hostbased(Authctxt *authctxt)
{
Buffer b;
- Key *key;
- char *pkalg, *pkblob, *sig, *cuser, *chost, *service;
+ Key *key = NULL;
+ char *pkalg, *cuser, *chost, *service;
+ u_char *pkblob, *sig;
u_int alen, blen, slen;
int pktype;
int authenticated = 0;
}
key = key_from_blob(pkblob, blen);
if (key == NULL) {
- debug("userauth_hostbased: cannot decode key: %s", pkalg);
+ error("userauth_hostbased: cannot decode key: %s", pkalg);
+ goto done;
+ }
+ if (key->type != pktype) {
+ error("userauth_hostbased: type mismatch for decoded key "
+ "(received %d, expected %d)", key->type, pktype);
goto done;
}
service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
buffer_dump(&b);
#endif
/* test for allowed key and correct signature */
- if (hostbased_key_allowed(authctxt->pw, cuser, chost, key) &&
- key_verify(key, sig, slen, buffer_ptr(&b), buffer_len(&b)) == 1)
+ authenticated = 0;
+ if (PRIVSEP(hostbased_key_allowed(authctxt->pw, cuser, chost, key)) &&
+ PRIVSEP(key_verify(key, sig, slen, buffer_ptr(&b),
+ buffer_len(&b))) == 1)
authenticated = 1;
buffer_clear(&b);
- key_free(key);
-
done:
debug2("userauth_hostbased: authenticated %d", authenticated);
+ if (key != NULL)
+ key_free(key);
xfree(pkalg);
xfree(pkblob);
xfree(cuser);
authmethods_get(void)
{
Authmethod *method = NULL;
- u_int size = 0;
+ Buffer b;
char *list;
+ buffer_init(&b);
for (method = authmethods; method->name != NULL; method++) {
if (strcmp(method->name, "none") == 0)
continue;
if (method->enabled != NULL && *(method->enabled) != 0) {
- if (size != 0)
- size += strlen(DELIM);
- size += strlen(method->name);
- }
- }
- size++; /* trailing '\0' */
- list = xmalloc(size);
- list[0] = '\0';
-
- for (method = authmethods; method->name != NULL; method++) {
- if (strcmp(method->name, "none") == 0)
- continue;
- if (method->enabled != NULL && *(method->enabled) != 0) {
- if (list[0] != '\0')
- strlcat(list, DELIM, size);
- strlcat(list, method->name, size);
+ if (buffer_len(&b) > 0)
+ buffer_append(&b, ",", 1);
+ buffer_append(&b, method->name, strlen(method->name));
}
}
+ buffer_append(&b, "\0", 1);
+ list = xstrdup(buffer_ptr(&b));
+ buffer_free(&b);
return list;
}
u_long linenum = 0;
struct stat st;
Key *found;
+ char *fp;
if (pw == NULL)
return 0;
found_key = 1;
debug("matching key found: file %s, line %lu",
file, linenum);
+ fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
+ verbose("Found matching %s key: %s",
+ key_type(found), fp);
+ xfree(fp);
break;
}
}
}
/* check whether given key is in .ssh/authorized_keys* */
-static int
+int
user_key_allowed(struct passwd *pw, Key *key)
{
int success;
}
/* return 1 if given hostkey is allowed */
-static int
+int
hostbased_key_allowed(struct passwd *pw, const char *cuser, char *chost,
Key *key)
{
HostStatus host_status;
int len;
- resolvedname = get_canonical_hostname(options.reverse_mapping_check);
+ resolvedname = get_canonical_hostname(options.verify_reverse_mapping);
ipaddr = get_remote_ipaddr();
debug2("userauth_hostbased: chost %s resolvedname %s ipaddr %s",
return (host_status == HOST_OK);
}
-