Commit 26e6991a authored by Magnus Hagander's avatar Magnus Hagander

Rearrange the code in auth.c so that all functions for a single authentication

method is grouped together in a reasonably similar way, keeping the "global
shared functions" together in their own section as well. Makes it a lot easier
to find your way around the code.
parent c30c1b87
...@@ -8,7 +8,7 @@ ...@@ -8,7 +8,7 @@
* *
* *
* IDENTIFICATION * IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/libpq/auth.c,v 1.166 2008/08/01 09:09:49 mha Exp $ * $PostgreSQL: pgsql/src/backend/libpq/auth.c,v 1.167 2008/08/01 11:41:12 mha Exp $
* *
*------------------------------------------------------------------------- *-------------------------------------------------------------------------
*/ */
...@@ -32,25 +32,33 @@ ...@@ -32,25 +32,33 @@
#include "libpq/pqformat.h" #include "libpq/pqformat.h"
#include "storage/ipc.h" #include "storage/ipc.h"
/*----------------------------------------------------------------
* Global authentication functions
*----------------------------------------------------------------
*/
static void sendAuthRequest(Port *port, AuthRequest areq); static void sendAuthRequest(Port *port, AuthRequest areq);
static void auth_failed(Port *port, int status); static void auth_failed(Port *port, int status);
static char *recv_password_packet(Port *port); static char *recv_password_packet(Port *port);
static int recv_and_check_password_packet(Port *port); static int recv_and_check_password_packet(Port *port);
static int authident(hbaPort *port);
char *pg_krb_server_keyfile;
char *pg_krb_srvnam;
bool pg_krb_caseins_users;
char *pg_krb_server_hostname = NULL;
char *pg_krb_realm = NULL;
/*----------------------------------------------------------------
* Ident authentication
*----------------------------------------------------------------
*/
/* Max size of username ident server can return */ /* Max size of username ident server can return */
#define IDENT_USERNAME_MAX 512 #define IDENT_USERNAME_MAX 512
/* Standard TCP port number for Ident service. Assigned by IANA */ /* Standard TCP port number for Ident service. Assigned by IANA */
#define IDENT_PORT 113 #define IDENT_PORT 113
static int authident(hbaPort *port);
/*----------------------------------------------------------------
* PAM authentication
*----------------------------------------------------------------
*/
#ifdef USE_PAM #ifdef USE_PAM
#ifdef HAVE_PAM_PAM_APPL_H #ifdef HAVE_PAM_PAM_APPL_H
#include <pam/pam_appl.h> #include <pam/pam_appl.h>
...@@ -75,6 +83,11 @@ static Port *pam_port_cludge; /* Workaround for passing "Port *port" into ...@@ -75,6 +83,11 @@ static Port *pam_port_cludge; /* Workaround for passing "Port *port" into
* pam_passwd_conv_proc */ * pam_passwd_conv_proc */
#endif /* USE_PAM */ #endif /* USE_PAM */
/*----------------------------------------------------------------
* LDAP authentication
*----------------------------------------------------------------
*/
#ifdef USE_LDAP #ifdef USE_LDAP
#ifndef WIN32 #ifndef WIN32
/* We use a deprecated function to keep the codepath the same as win32. */ /* We use a deprecated function to keep the codepath the same as win32. */
...@@ -95,21 +108,33 @@ ULONG(*__ldap_start_tls_sA) ( ...@@ -95,21 +108,33 @@ ULONG(*__ldap_start_tls_sA) (
#endif #endif
static int CheckLDAPAuth(Port *port); static int CheckLDAPAuth(Port *port);
#endif #endif /* USE_LDAP */
/*----------------------------------------------------------------
* Kerberos and GSSAPI GUCs
*----------------------------------------------------------------
*/
char *pg_krb_server_keyfile;
char *pg_krb_srvnam;
bool pg_krb_caseins_users;
char *pg_krb_server_hostname = NULL;
char *pg_krb_realm = NULL;
#ifdef KRB5
/*---------------------------------------------------------------- /*----------------------------------------------------------------
* MIT Kerberos authentication system - protocol version 5 * MIT Kerberos authentication system - protocol version 5
*---------------------------------------------------------------- *----------------------------------------------------------------
*/ */
static int pg_krb5_recvauth(Port *port);
#ifdef KRB5
#include <krb5.h> #include <krb5.h>
/* Some old versions of Kerberos do not include <com_err.h> in <krb5.h> */ /* Some old versions of Kerberos do not include <com_err.h> in <krb5.h> */
#if !defined(__COM_ERR_H) && !defined(__COM_ERR_H__) #if !defined(__COM_ERR_H) && !defined(__COM_ERR_H__)
#include <com_err.h> #include <com_err.h>
#endif #endif
/* /*
* Various krb5 state which is not connection specfic, and a flag to * Various krb5 state which is not connection specfic, and a flag to
* indicate whether we have initialised it yet. * indicate whether we have initialised it yet.
...@@ -118,458 +143,549 @@ static int pg_krb5_initialised; ...@@ -118,458 +143,549 @@ static int pg_krb5_initialised;
static krb5_context pg_krb5_context; static krb5_context pg_krb5_context;
static krb5_keytab pg_krb5_keytab; static krb5_keytab pg_krb5_keytab;
static krb5_principal pg_krb5_server; static krb5_principal pg_krb5_server;
#endif /* KRB5 */
static int /*----------------------------------------------------------------
pg_krb5_init(void) * GSSAPI Authentication
{ *----------------------------------------------------------------
krb5_error_code retval; */
char *khostname; static int pg_GSS_recvauth(Port *port);
if (pg_krb5_initialised) #ifdef ENABLE_GSS
return STATUS_OK; #if defined(HAVE_GSSAPI_H)
#include <gssapi.h>
#else
#include <gssapi/gssapi.h>
#endif
#endif /* ENABLE_GSS */
retval = krb5_init_context(&pg_krb5_context);
if (retval)
{
ereport(LOG,
(errmsg("Kerberos initialization returned error %d",
retval)));
com_err("postgres", retval, "while initializing krb5");
return STATUS_ERROR;
}
retval = krb5_kt_resolve(pg_krb5_context, pg_krb_server_keyfile, &pg_krb5_keytab); /*----------------------------------------------------------------
if (retval) * SSPI Authentication
{ *----------------------------------------------------------------
ereport(LOG, */
(errmsg("Kerberos keytab resolving returned error %d", static int pg_SSPI_recvauth(Port *port);
retval)));
com_err("postgres", retval, "while resolving keytab file \"%s\"",
pg_krb_server_keyfile);
krb5_free_context(pg_krb5_context);
return STATUS_ERROR;
}
/* #ifdef ENABLE_SSPI
* If no hostname was specified, pg_krb_server_hostname is already NULL. typedef SECURITY_STATUS
* If it's set to blank, force it to NULL. (WINAPI * QUERY_SECURITY_CONTEXT_TOKEN_FN) (
*/ PCtxtHandle, void **);
khostname = pg_krb_server_hostname; #endif
if (khostname && khostname[0] == '\0')
khostname = NULL;
retval = krb5_sname_to_principal(pg_krb5_context,
khostname,
pg_krb_srvnam,
KRB5_NT_SRV_HST,
&pg_krb5_server);
if (retval)
{
ereport(LOG,
(errmsg("Kerberos sname_to_principal(\"%s\", \"%s\") returned error %d",
khostname ? khostname : "server hostname", pg_krb_srvnam, retval)));
com_err("postgres", retval,
"while getting server principal for server \"%s\" for service \"%s\"",
khostname ? khostname : "server hostname", pg_krb_srvnam);
krb5_kt_close(pg_krb5_context, pg_krb5_keytab);
krb5_free_context(pg_krb5_context);
return STATUS_ERROR;
}
pg_krb5_initialised = 1;
return STATUS_OK; /*----------------------------------------------------------------
} * Global authentication functions
*----------------------------------------------------------------
*/
/* /*
* pg_krb5_recvauth -- server routine to receive authentication information * Tell the user the authentication failed, but not (much about) why.
* from the client
*
* We still need to compare the username obtained from the client's setup
* packet to the authenticated name.
* *
* We have our own keytab file because postgres is unlikely to run as root, * There is a tradeoff here between security concerns and making life
* and so cannot read the default keytab. * unnecessarily difficult for legitimate users. We would not, for example,
* want to report the password we were expecting to receive...
* But it seems useful to report the username and authorization method
* in use, and these are items that must be presumed known to an attacker
* anyway.
* Note that many sorts of failure report additional information in the
* postmaster log, which we hope is only readable by good guys.
*/ */
static int static void
pg_krb5_recvauth(Port *port) auth_failed(Port *port, int status)
{ {
krb5_error_code retval; const char *errstr;
int ret;
krb5_auth_context auth_context = NULL;
krb5_ticket *ticket;
char *kusername;
char *cp;
if (get_role_line(port->user_name) == NULL)
return STATUS_ERROR;
ret = pg_krb5_init(); /*
if (ret != STATUS_OK) * If we failed due to EOF from client, just quit; there's no point in
return ret; * trying to send a message to the client, and not much point in logging
* the failure in the postmaster log. (Logging the failure might be
* desirable, were it not for the fact that libpq closes the connection
* unceremoniously if challenged for a password when it hasn't got one to
* send. We'll get a useless log entry for every psql connection under
* password auth, even if it's perfectly successful, if we log STATUS_EOF
* events.)
*/
if (status == STATUS_EOF)
proc_exit(0);
retval = krb5_recvauth(pg_krb5_context, &auth_context, switch (port->auth_method)
(krb5_pointer) & port->sock, pg_krb_srvnam,
pg_krb5_server, 0, pg_krb5_keytab, &ticket);
if (retval)
{ {
ereport(LOG, case uaReject:
(errmsg("Kerberos recvauth returned error %d", errstr = gettext_noop("authentication failed for user \"%s\": host rejected");
retval))); break;
com_err("postgres", retval, "from krb5_recvauth"); case uaKrb5:
return STATUS_ERROR; errstr = gettext_noop("Kerberos 5 authentication failed for user \"%s\"");
break;
case uaGSS:
errstr = gettext_noop("GSSAPI authentication failed for user \"%s\"");
break;
case uaSSPI:
errstr = gettext_noop("SSPI authentication failed for user \"%s\"");
break;
case uaTrust:
errstr = gettext_noop("\"trust\" authentication failed for user \"%s\"");
break;
case uaIdent:
errstr = gettext_noop("Ident authentication failed for user \"%s\"");
break;
case uaMD5:
case uaCrypt:
case uaPassword:
errstr = gettext_noop("password authentication failed for user \"%s\"");
break;
#ifdef USE_PAM
case uaPAM:
errstr = gettext_noop("PAM authentication failed for user \"%s\"");
break;
#endif /* USE_PAM */
#ifdef USE_LDAP
case uaLDAP:
errstr = gettext_noop("LDAP authentication failed for user \"%s\"");
break;
#endif /* USE_LDAP */
default:
errstr = gettext_noop("authentication failed for user \"%s\": invalid authentication method");
break;
} }
ereport(FATAL,
(errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
errmsg(errstr, port->user_name)));
/* doesn't return */
}
/*
* Client authentication starts here. If there is an error, this
* function does not return and the backend process is terminated.
*/
void
ClientAuthentication(Port *port)
{
int status = STATUS_ERROR;
/* /*
* The "client" structure comes out of the ticket and is therefore * Get the authentication method to use for this frontend/database
* authenticated. Use it to check the username obtained from the * combination. Note: a failure return indicates a problem with the hba
* postmaster startup packet. * config file, not with the request. hba.c should have dropped an error
* message into the postmaster logfile if it failed.
*/ */
#if defined(HAVE_KRB5_TICKET_ENC_PART2) if (hba_getauthmethod(port) != STATUS_OK)
retval = krb5_unparse_name(pg_krb5_context, ereport(FATAL,
ticket->enc_part2->client, &kusername); (errcode(ERRCODE_CONFIG_FILE_ERROR),
#elif defined(HAVE_KRB5_TICKET_CLIENT) errmsg("missing or erroneous pg_hba.conf file"),
retval = krb5_unparse_name(pg_krb5_context, errhint("See server log for details.")));
ticket->client, &kusername);
#else
#error "bogus configuration"
#endif
if (retval)
{
ereport(LOG,
(errmsg("Kerberos unparse_name returned error %d",
retval)));
com_err("postgres", retval, "while unparsing client name");
krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
return STATUS_ERROR;
}
cp = strchr(kusername, '@'); switch (port->auth_method)
if (cp)
{ {
*cp = '\0'; case uaReject:
cp++;
if (pg_krb_realm != NULL && strlen(pg_krb_realm))
{
/* Match realm against configured */
if (pg_krb_caseins_users)
ret = pg_strcasecmp(pg_krb_realm, cp);
else
ret = strcmp(pg_krb_realm, cp);
if (ret) /*
* This could have come from an explicit "reject" entry in
* pg_hba.conf, but more likely it means there was no matching
* entry. Take pity on the poor user and issue a helpful error
* message. NOTE: this is not a security breach, because all the
* info reported here is known at the frontend and must be assumed
* known to bad guys. We're merely helping out the less clueful
* good guys.
*/
{ {
elog(DEBUG2, char hostinfo[NI_MAXHOST];
"krb5 realm (%s) and configured realm (%s) don't match",
cp, pg_krb_realm);
krb5_free_ticket(pg_krb5_context, ticket); pg_getnameinfo_all(&port->raddr.addr, port->raddr.salen,
krb5_auth_con_free(pg_krb5_context, auth_context); hostinfo, sizeof(hostinfo),
return STATUS_ERROR; NULL, 0,
NI_NUMERICHOST);
#ifdef USE_SSL
ereport(FATAL,
(errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
errmsg("no pg_hba.conf entry for host \"%s\", user \"%s\", database \"%s\", %s",
hostinfo, port->user_name, port->database_name,
port->ssl ? _("SSL on") : _("SSL off"))));
#else
ereport(FATAL,
(errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
errmsg("no pg_hba.conf entry for host \"%s\", user \"%s\", database \"%s\"",
hostinfo, port->user_name, port->database_name)));
#endif
break;
} }
}
}
else if (pg_krb_realm && strlen(pg_krb_realm))
{
elog(DEBUG2,
"krb5 did not return realm but realm matching was requested");
krb5_free_ticket(pg_krb5_context, ticket); case uaKrb5:
krb5_auth_con_free(pg_krb5_context, auth_context); sendAuthRequest(port, AUTH_REQ_KRB5);
return STATUS_ERROR; status = pg_krb5_recvauth(port);
} break;
if (pg_krb_caseins_users) case uaGSS:
ret = pg_strncasecmp(port->user_name, kusername, SM_DATABASE_USER); sendAuthRequest(port, AUTH_REQ_GSS);
else status = pg_GSS_recvauth(port);
ret = strncmp(port->user_name, kusername, SM_DATABASE_USER); break;
if (ret)
{
ereport(LOG,
(errmsg("unexpected Kerberos user name received from client (received \"%s\", expected \"%s\")",
port->user_name, kusername)));
ret = STATUS_ERROR;
}
else
ret = STATUS_OK;
krb5_free_ticket(pg_krb5_context, ticket); case uaSSPI:
krb5_auth_con_free(pg_krb5_context, auth_context); sendAuthRequest(port, AUTH_REQ_SSPI);
free(kusername); status = pg_SSPI_recvauth(port);
break;
return ret; case uaIdent:
}
#else
static int /*
pg_krb5_recvauth(Port *port) * If we are doing ident on unix-domain sockets, use SCM_CREDS
{ * only if it is defined and SO_PEERCRED isn't.
ereport(LOG, */
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED), #if !defined(HAVE_GETPEEREID) && !defined(SO_PEERCRED) && \
errmsg("Kerberos 5 not implemented on this server"))); (defined(HAVE_STRUCT_CMSGCRED) || defined(HAVE_STRUCT_FCRED) || \
return STATUS_ERROR; (defined(HAVE_STRUCT_SOCKCRED) && defined(LOCAL_CREDS)))
} if (port->raddr.addr.ss_family == AF_UNIX)
#endif /* KRB5 */ {
#if defined(HAVE_STRUCT_FCRED) || defined(HAVE_STRUCT_SOCKCRED)
/*---------------------------------------------------------------- /*
* GSSAPI authentication system * Receive credentials on next message receipt, BSD/OS,
*---------------------------------------------------------------- * NetBSD. We need to set this before the client sends the
*/ * next packet.
*/
int on = 1;
#ifdef ENABLE_GSS if (setsockopt(port->sock, 0, LOCAL_CREDS, &on, sizeof(on)) < 0)
ereport(FATAL,
(errcode_for_socket_access(),
errmsg("could not enable credential reception: %m")));
#endif
#if defined(HAVE_GSSAPI_H) sendAuthRequest(port, AUTH_REQ_SCM_CREDS);
#include <gssapi.h> }
#else
#include <gssapi/gssapi.h>
#endif #endif
status = authident(port);
break;
#if defined(WIN32) && !defined(WIN32_ONLY_COMPILER) case uaMD5:
/* sendAuthRequest(port, AUTH_REQ_MD5);
* MIT Kerberos GSSAPI DLL doesn't properly export the symbols for MingW status = recv_and_check_password_packet(port);
* that contain the OIDs required. Redefine here, values copied break;
* from src/athena/auth/krb5/src/lib/gssapi/generic/gssapi_generic.c
*/ case uaCrypt:
static const gss_OID_desc GSS_C_NT_USER_NAME_desc = sendAuthRequest(port, AUTH_REQ_CRYPT);
{10, (void *) "\x2a\x86\x48\x86\xf7\x12\x01\x02\x01\x02"}; status = recv_and_check_password_packet(port);
static GSS_DLLIMP gss_OID GSS_C_NT_USER_NAME = &GSS_C_NT_USER_NAME_desc; break;
case uaPassword:
sendAuthRequest(port, AUTH_REQ_PASSWORD);
status = recv_and_check_password_packet(port);
break;
#ifdef USE_PAM
case uaPAM:
pam_port_cludge = port;
status = CheckPAMAuth(port, port->user_name, "");
break;
#endif /* USE_PAM */
#ifdef USE_LDAP
case uaLDAP:
status = CheckLDAPAuth(port);
break;
#endif #endif
case uaTrust:
status = STATUS_OK;
break;
}
if (status == STATUS_OK)
sendAuthRequest(port, AUTH_REQ_OK);
else
auth_failed(port, status);
}
/*
* Send an authentication request packet to the frontend.
*/
static void static void
pg_GSS_error(int severity, char *errmsg, OM_uint32 maj_stat, OM_uint32 min_stat) sendAuthRequest(Port *port, AuthRequest areq)
{ {
gss_buffer_desc gmsg; StringInfoData buf;
OM_uint32 lmaj_s,
lmin_s,
msg_ctx;
char msg_major[128],
msg_minor[128];
/* Fetch major status message */ pq_beginmessage(&buf, 'R');
msg_ctx = 0; pq_sendint(&buf, (int32) areq, sizeof(int32));
lmaj_s = gss_display_status(&lmin_s, maj_stat, GSS_C_GSS_CODE,
GSS_C_NO_OID, &msg_ctx, &gmsg);
strlcpy(msg_major, gmsg.value, sizeof(msg_major));
gss_release_buffer(&lmin_s, &gmsg);
if (msg_ctx) /* Add the salt for encrypted passwords. */
if (areq == AUTH_REQ_MD5)
pq_sendbytes(&buf, port->md5Salt, 4);
else if (areq == AUTH_REQ_CRYPT)
pq_sendbytes(&buf, port->cryptSalt, 2);
/* #if defined(ENABLE_GSS) || defined(ENABLE_SSPI)
* More than one message available. XXX: Should we loop and read all
* messages? (same below)
*/
ereport(WARNING,
(errmsg_internal("incomplete GSS error report")));
/* Fetch mechanism minor status message */ /*
msg_ctx = 0; * Add the authentication data for the next step of the GSSAPI or SSPI
lmaj_s = gss_display_status(&lmin_s, min_stat, GSS_C_MECH_CODE, * negotiation.
GSS_C_NO_OID, &msg_ctx, &gmsg); */
strlcpy(msg_minor, gmsg.value, sizeof(msg_minor)); else if (areq == AUTH_REQ_GSS_CONT)
gss_release_buffer(&lmin_s, &gmsg); {
if (port->gss->outbuf.length > 0)
{
elog(DEBUG4, "sending GSS token of length %u",
(unsigned int) port->gss->outbuf.length);
if (msg_ctx) pq_sendbytes(&buf, port->gss->outbuf.value, port->gss->outbuf.length);
ereport(WARNING, }
(errmsg_internal("incomplete GSS minor error report"))); }
#endif
pq_endmessage(&buf);
/* /*
* errmsg_internal, since translation of the first part must be done * Flush message so client will see it, except for AUTH_REQ_OK, which need
* before calling this function anyway. * not be sent until we are ready for queries.
*/ */
ereport(severity, if (areq != AUTH_REQ_OK)
(errmsg_internal("%s", errmsg), pq_flush();
errdetail("%s: %s", msg_major, msg_minor)));
} }
static int /*
pg_GSS_recvauth(Port *port) * Collect password response packet from frontend.
*
* Returns NULL if couldn't get password, else palloc'd string.
*/
static char *
recv_password_packet(Port *port)
{ {
OM_uint32 maj_stat,
min_stat,
lmin_s,
gflags;
int mtype;
int ret;
StringInfoData buf; StringInfoData buf;
gss_buffer_desc gbuf;
/*
* GSS auth is not supported for protocol versions before 3, because it
* relies on the overall message length word to determine the GSS payload
* size in AuthenticationGSSContinue and PasswordMessage messages.
* (This is, in fact, a design error in our GSS support, because protocol
* messages are supposed to be parsable without relying on the length
* word; but it's not worth changing it now.)
*/
if (PG_PROTOCOL_MAJOR(FrontendProtocol) < 3)
ereport(FATAL,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("GSSAPI is not supported in protocol version 2")));
if (pg_krb_server_keyfile && strlen(pg_krb_server_keyfile) > 0) if (PG_PROTOCOL_MAJOR(port->proto) >= 3)
{ {
/* /* Expect 'p' message type */
* Set default Kerberos keytab file for the Krb5 mechanism. int mtype;
*
* setenv("KRB5_KTNAME", pg_krb_server_keyfile, 0); except setenv()
* not always available.
*/
if (getenv("KRB5_KTNAME") == NULL)
{
size_t kt_len = strlen(pg_krb_server_keyfile) + 14;
char *kt_path = malloc(kt_len);
if (!kt_path) mtype = pq_getbyte();
{ if (mtype != 'p')
ereport(LOG, {
(errcode(ERRCODE_OUT_OF_MEMORY), /*
errmsg("out of memory"))); * If the client just disconnects without offering a password,
return STATUS_ERROR; * don't make a log entry. This is legal per protocol spec and in
} * fact commonly done by psql, so complaining just clutters the
snprintf(kt_path, kt_len, "KRB5_KTNAME=%s", pg_krb_server_keyfile); * log.
putenv(kt_path); */
if (mtype != EOF)
ereport(COMMERROR,
(errcode(ERRCODE_PROTOCOL_VIOLATION),
errmsg("expected password response, got message type %d",
mtype)));
return NULL; /* EOF or bad message type */
} }
} }
else
{
/* For pre-3.0 clients, avoid log entry if they just disconnect */
if (pq_peekbyte() == EOF)
return NULL; /* EOF */
}
/* initStringInfo(&buf);
* We accept any service principal that's present in our keytab. This if (pq_getmessage(&buf, 1000)) /* receive password */
* increases interoperability between kerberos implementations that see {
* for example case sensitivity differently, while not really opening up /* EOF - pq_getmessage already logged a suitable message */
* any vector of attack. pfree(buf.data);
*/ return NULL;
port->gss->cred = GSS_C_NO_CREDENTIAL; }
/* /*
* Initialize sequence with an empty context * Apply sanity check: password packet length should agree with length of
* contained string. Note it is safe to use strlen here because
* StringInfo is guaranteed to have an appended '\0'.
*/ */
port->gss->ctx = GSS_C_NO_CONTEXT; if (strlen(buf.data) + 1 != buf.len)
ereport(COMMERROR,
(errcode(ERRCODE_PROTOCOL_VIOLATION),
errmsg("invalid password packet size")));
/* Do not echo password to logs, for security. */
ereport(DEBUG5,
(errmsg("received password packet")));
/* /*
* Loop through GSSAPI message exchange. This exchange can consist of * Return the received string. Note we do not attempt to do any
* multiple messags sent in both directions. First message is always from * character-set conversion on it; since we don't yet know the client's
* the client. All messages from client to server are password packets * encoding, there wouldn't be much point.
* (type 'p').
*/ */
do return buf.data;
{ }
mtype = pq_getbyte();
if (mtype != 'p')
{
/* Only log error if client didn't disconnect. */
if (mtype != EOF)
ereport(COMMERROR,
(errcode(ERRCODE_PROTOCOL_VIOLATION),
errmsg("expected GSS response, got message type %d",
mtype)));
return STATUS_ERROR;
}
/* Get the actual GSS token */
initStringInfo(&buf);
if (pq_getmessage(&buf, 2000))
{
/* EOF - pq_getmessage already logged error */
pfree(buf.data);
return STATUS_ERROR;
}
/* Map to GSSAPI style buffer */
gbuf.length = buf.len;
gbuf.value = buf.data;
elog(DEBUG4, "Processing received GSS token of length %u", /*----------------------------------------------------------------
(unsigned int) gbuf.length); * MD5 and crypt authentication
*----------------------------------------------------------------
*/
maj_stat = gss_accept_sec_context( /*
&min_stat, * Called when we have sent an authorization request for a password.
&port->gss->ctx, * Get the response and check it.
port->gss->cred, */
&gbuf, static int
GSS_C_NO_CHANNEL_BINDINGS, recv_and_check_password_packet(Port *port)
&port->gss->name, {
NULL, char *passwd;
&port->gss->outbuf, int result;
&gflags,
NULL,
NULL);
/* gbuf no longer used */ passwd = recv_password_packet(port);
pfree(buf.data);
elog(DEBUG5, "gss_accept_sec_context major: %d, " if (passwd == NULL)
"minor: %d, outlen: %u, outflags: %x", return STATUS_EOF; /* client wouldn't send password */
maj_stat, min_stat,
(unsigned int) port->gss->outbuf.length, gflags);
if (port->gss->outbuf.length != 0) result = md5_crypt_verify(port, port->user_name, passwd);
{
/*
* Negotiation generated data to be sent to the client.
*/
OM_uint32 lmin_s;
elog(DEBUG4, "sending GSS response token of length %u", pfree(passwd);
(unsigned int) port->gss->outbuf.length);
sendAuthRequest(port, AUTH_REQ_GSS_CONT); return result;
}
gss_release_buffer(&lmin_s, &port->gss->outbuf);
}
if (maj_stat != GSS_S_COMPLETE && maj_stat != GSS_S_CONTINUE_NEEDED) /*----------------------------------------------------------------
{ * MIT Kerberos authentication system - protocol version 5
OM_uint32 lmin_s; *----------------------------------------------------------------
*/
#ifdef KRB5
gss_delete_sec_context(&lmin_s, &port->gss->ctx, GSS_C_NO_BUFFER); static int
pg_GSS_error(ERROR, pg_krb5_init(void)
gettext_noop("accepting GSS security context failed"), {
maj_stat, min_stat); krb5_error_code retval;
} char *khostname;
if (maj_stat == GSS_S_CONTINUE_NEEDED) if (pg_krb5_initialised)
elog(DEBUG4, "GSS continue needed"); return STATUS_OK;
} while (maj_stat == GSS_S_CONTINUE_NEEDED); retval = krb5_init_context(&pg_krb5_context);
if (retval)
{
ereport(LOG,
(errmsg("Kerberos initialization returned error %d",
retval)));
com_err("postgres", retval, "while initializing krb5");
return STATUS_ERROR;
}
if (port->gss->cred != GSS_C_NO_CREDENTIAL) retval = krb5_kt_resolve(pg_krb5_context, pg_krb_server_keyfile, &pg_krb5_keytab);
if (retval)
{ {
/* ereport(LOG,
* Release service principal credentials (errmsg("Kerberos keytab resolving returned error %d",
*/ retval)));
gss_release_cred(&min_stat, &port->gss->cred); com_err("postgres", retval, "while resolving keytab file \"%s\"",
pg_krb_server_keyfile);
krb5_free_context(pg_krb5_context);
return STATUS_ERROR;
} }
/* /*
* GSS_S_COMPLETE indicates that authentication is now complete. * If no hostname was specified, pg_krb_server_hostname is already NULL.
* * If it's set to blank, force it to NULL.
* Get the name of the user that authenticated, and compare it to the pg
* username that was specified for the connection.
*/ */
maj_stat = gss_display_name(&min_stat, port->gss->name, &gbuf, NULL); khostname = pg_krb_server_hostname;
if (maj_stat != GSS_S_COMPLETE) if (khostname && khostname[0] == '\0')
pg_GSS_error(ERROR, khostname = NULL;
gettext_noop("retrieving GSS user name failed"),
maj_stat, min_stat);
/* retval = krb5_sname_to_principal(pg_krb5_context,
* Split the username at the realm separator khostname,
*/ pg_krb_srvnam,
if (strchr(gbuf.value, '@')) KRB5_NT_SRV_HST,
&pg_krb5_server);
if (retval)
{ {
char *cp = strchr(gbuf.value, '@'); ereport(LOG,
(errmsg("Kerberos sname_to_principal(\"%s\", \"%s\") returned error %d",
khostname ? khostname : "server hostname", pg_krb_srvnam, retval)));
com_err("postgres", retval,
"while getting server principal for server \"%s\" for service \"%s\"",
khostname ? khostname : "server hostname", pg_krb_srvnam);
krb5_kt_close(pg_krb5_context, pg_krb5_keytab);
krb5_free_context(pg_krb5_context);
return STATUS_ERROR;
}
*cp = '\0'; pg_krb5_initialised = 1;
cp++; return STATUS_OK;
}
/*
* pg_krb5_recvauth -- server routine to receive authentication information
* from the client
*
* We still need to compare the username obtained from the client's setup
* packet to the authenticated name.
*
* We have our own keytab file because postgres is unlikely to run as root,
* and so cannot read the default keytab.
*/
static int
pg_krb5_recvauth(Port *port)
{
krb5_error_code retval;
int ret;
krb5_auth_context auth_context = NULL;
krb5_ticket *ticket;
char *kusername;
char *cp;
if (get_role_line(port->user_name) == NULL)
return STATUS_ERROR;
ret = pg_krb5_init();
if (ret != STATUS_OK)
return ret;
retval = krb5_recvauth(pg_krb5_context, &auth_context,
(krb5_pointer) & port->sock, pg_krb_srvnam,
pg_krb5_server, 0, pg_krb5_keytab, &ticket);
if (retval)
{
ereport(LOG,
(errmsg("Kerberos recvauth returned error %d",
retval)));
com_err("postgres", retval, "from krb5_recvauth");
return STATUS_ERROR;
}
/*
* The "client" structure comes out of the ticket and is therefore
* authenticated. Use it to check the username obtained from the
* postmaster startup packet.
*/
#if defined(HAVE_KRB5_TICKET_ENC_PART2)
retval = krb5_unparse_name(pg_krb5_context,
ticket->enc_part2->client, &kusername);
#elif defined(HAVE_KRB5_TICKET_CLIENT)
retval = krb5_unparse_name(pg_krb5_context,
ticket->client, &kusername);
#else
#error "bogus configuration"
#endif
if (retval)
{
ereport(LOG,
(errmsg("Kerberos unparse_name returned error %d",
retval)));
com_err("postgres", retval, "while unparsing client name");
krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
return STATUS_ERROR;
}
cp = strchr(kusername, '@');
if (cp)
{
*cp = '\0';
cp++;
if (pg_krb_realm != NULL && strlen(pg_krb_realm)) if (pg_krb_realm != NULL && strlen(pg_krb_realm))
{ {
/* /* Match realm against configured */
* Match the realm part of the name first
*/
if (pg_krb_caseins_users) if (pg_krb_caseins_users)
ret = pg_strcasecmp(pg_krb_realm, cp); ret = pg_strcasecmp(pg_krb_realm, cp);
else else
...@@ -577,11 +693,12 @@ pg_GSS_recvauth(Port *port) ...@@ -577,11 +693,12 @@ pg_GSS_recvauth(Port *port)
if (ret) if (ret)
{ {
/* GSS realm does not match */
elog(DEBUG2, elog(DEBUG2,
"GSSAPI realm (%s) and configured realm (%s) don't match", "krb5 realm (%s) and configured realm (%s) don't match",
cp, pg_krb_realm); cp, pg_krb_realm);
gss_release_buffer(&lmin_s, &gbuf);
krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
return STATUS_ERROR; return STATUS_ERROR;
} }
} }
...@@ -589,116 +706,419 @@ pg_GSS_recvauth(Port *port) ...@@ -589,116 +706,419 @@ pg_GSS_recvauth(Port *port)
else if (pg_krb_realm && strlen(pg_krb_realm)) else if (pg_krb_realm && strlen(pg_krb_realm))
{ {
elog(DEBUG2, elog(DEBUG2,
"GSSAPI did not return realm but realm matching was requested"); "krb5 did not return realm but realm matching was requested");
gss_release_buffer(&lmin_s, &gbuf); krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
return STATUS_ERROR; return STATUS_ERROR;
} }
if (pg_krb_caseins_users) if (pg_krb_caseins_users)
ret = pg_strcasecmp(port->user_name, gbuf.value); ret = pg_strncasecmp(port->user_name, kusername, SM_DATABASE_USER);
else else
ret = strcmp(port->user_name, gbuf.value); ret = strncmp(port->user_name, kusername, SM_DATABASE_USER);
if (ret) if (ret)
{ {
/* GSS name and PGUSER are not equivalent */ ereport(LOG,
elog(DEBUG2, (errmsg("unexpected Kerberos user name received from client (received \"%s\", expected \"%s\")",
"provided username (%s) and GSSAPI username (%s) don't match", port->user_name, kusername)));
port->user_name, (char *) gbuf.value); ret = STATUS_ERROR;
gss_release_buffer(&lmin_s, &gbuf);
return STATUS_ERROR;
} }
else
ret = STATUS_OK;
gss_release_buffer(&lmin_s, &gbuf); krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
free(kusername);
return STATUS_OK; return ret;
} }
#else
#else /* no ENABLE_GSS */
static int static int
pg_GSS_recvauth(Port *port) pg_krb5_recvauth(Port *port)
{ {
ereport(LOG, ereport(LOG,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED), (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("GSSAPI not implemented on this server"))); errmsg("Kerberos 5 not implemented on this server")));
return STATUS_ERROR; return STATUS_ERROR;
} }
#endif /* KRB5 */
#endif /* ENABLE_GSS */
/*---------------------------------------------------------------- /*----------------------------------------------------------------
* SSPI authentication system * GSSAPI authentication system
*---------------------------------------------------------------- *----------------------------------------------------------------
*/ */
#ifdef ENABLE_GSS
#ifdef ENABLE_SSPI #if defined(WIN32) && !defined(WIN32_ONLY_COMPILER)
/*
* MIT Kerberos GSSAPI DLL doesn't properly export the symbols for MingW
* that contain the OIDs required. Redefine here, values copied
* from src/athena/auth/krb5/src/lib/gssapi/generic/gssapi_generic.c
*/
static const gss_OID_desc GSS_C_NT_USER_NAME_desc =
{10, (void *) "\x2a\x86\x48\x86\xf7\x12\x01\x02\x01\x02"};
static GSS_DLLIMP gss_OID GSS_C_NT_USER_NAME = &GSS_C_NT_USER_NAME_desc;
#endif
typedef SECURITY_STATUS
(WINAPI * QUERY_SECURITY_CONTEXT_TOKEN_FN) (
PCtxtHandle, void **);
static void static void
pg_SSPI_error(int severity, char *errmsg, SECURITY_STATUS r) pg_GSS_error(int severity, char *errmsg, OM_uint32 maj_stat, OM_uint32 min_stat)
{ {
char sysmsg[256]; gss_buffer_desc gmsg;
OM_uint32 lmaj_s,
lmin_s,
msg_ctx;
char msg_major[128],
msg_minor[128];
if (FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, r, 0, sysmsg, sizeof(sysmsg), NULL) == 0) /* Fetch major status message */
ereport(severity, msg_ctx = 0;
(errmsg_internal("%s", errmsg), lmaj_s = gss_display_status(&lmin_s, maj_stat, GSS_C_GSS_CODE,
errdetail("SSPI error %x", (unsigned int) r))); GSS_C_NO_OID, &msg_ctx, &gmsg);
else strlcpy(msg_major, gmsg.value, sizeof(msg_major));
ereport(severity, gss_release_buffer(&lmin_s, &gmsg);
(errmsg_internal("%s", errmsg),
errdetail("%s (%x)", sysmsg, (unsigned int) r))); if (msg_ctx)
/*
* More than one message available. XXX: Should we loop and read all
* messages? (same below)
*/
ereport(WARNING,
(errmsg_internal("incomplete GSS error report")));
/* Fetch mechanism minor status message */
msg_ctx = 0;
lmaj_s = gss_display_status(&lmin_s, min_stat, GSS_C_MECH_CODE,
GSS_C_NO_OID, &msg_ctx, &gmsg);
strlcpy(msg_minor, gmsg.value, sizeof(msg_minor));
gss_release_buffer(&lmin_s, &gmsg);
if (msg_ctx)
ereport(WARNING,
(errmsg_internal("incomplete GSS minor error report")));
/*
* errmsg_internal, since translation of the first part must be done
* before calling this function anyway.
*/
ereport(severity,
(errmsg_internal("%s", errmsg),
errdetail("%s: %s", msg_major, msg_minor)));
} }
static int static int
pg_SSPI_recvauth(Port *port) pg_GSS_recvauth(Port *port)
{ {
OM_uint32 maj_stat,
min_stat,
lmin_s,
gflags;
int mtype; int mtype;
int ret;
StringInfoData buf; StringInfoData buf;
SECURITY_STATUS r; gss_buffer_desc gbuf;
CredHandle sspicred;
CtxtHandle *sspictx = NULL,
newctx;
TimeStamp expiry;
ULONG contextattr;
SecBufferDesc inbuf;
SecBufferDesc outbuf;
SecBuffer OutBuffers[1];
SecBuffer InBuffers[1];
HANDLE token;
TOKEN_USER *tokenuser;
DWORD retlen;
char accountname[MAXPGPATH];
char domainname[MAXPGPATH];
DWORD accountnamesize = sizeof(accountname);
DWORD domainnamesize = sizeof(domainname);
SID_NAME_USE accountnameuse;
HMODULE secur32;
QUERY_SECURITY_CONTEXT_TOKEN_FN _QuerySecurityContextToken;
/* /*
* SSPI auth is not supported for protocol versions before 3, because it * GSS auth is not supported for protocol versions before 3, because it
* relies on the overall message length word to determine the SSPI payload * relies on the overall message length word to determine the GSS payload
* size in AuthenticationGSSContinue and PasswordMessage messages. * size in AuthenticationGSSContinue and PasswordMessage messages.
* (This is, in fact, a design error in our SSPI support, because protocol * (This is, in fact, a design error in our GSS support, because protocol
* messages are supposed to be parsable without relying on the length * messages are supposed to be parsable without relying on the length
* word; but it's not worth changing it now.) * word; but it's not worth changing it now.)
*/ */
if (PG_PROTOCOL_MAJOR(FrontendProtocol) < 3) if (PG_PROTOCOL_MAJOR(FrontendProtocol) < 3)
ereport(FATAL, ereport(FATAL,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED), (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SSPI is not supported in protocol version 2"))); errmsg("GSSAPI is not supported in protocol version 2")));
if (pg_krb_server_keyfile && strlen(pg_krb_server_keyfile) > 0)
{
/*
* Set default Kerberos keytab file for the Krb5 mechanism.
*
* setenv("KRB5_KTNAME", pg_krb_server_keyfile, 0); except setenv()
* not always available.
*/
if (getenv("KRB5_KTNAME") == NULL)
{
size_t kt_len = strlen(pg_krb_server_keyfile) + 14;
char *kt_path = malloc(kt_len);
if (!kt_path)
{
ereport(LOG,
(errcode(ERRCODE_OUT_OF_MEMORY),
errmsg("out of memory")));
return STATUS_ERROR;
}
snprintf(kt_path, kt_len, "KRB5_KTNAME=%s", pg_krb_server_keyfile);
putenv(kt_path);
}
}
/* /*
* Acquire a handle to the server credentials. * We accept any service principal that's present in our keytab. This
* increases interoperability between kerberos implementations that see
* for example case sensitivity differently, while not really opening up
* any vector of attack.
*/ */
r = AcquireCredentialsHandle(NULL, port->gss->cred = GSS_C_NO_CREDENTIAL;
"negotiate",
/*
* Initialize sequence with an empty context
*/
port->gss->ctx = GSS_C_NO_CONTEXT;
/*
* Loop through GSSAPI message exchange. This exchange can consist of
* multiple messags sent in both directions. First message is always from
* the client. All messages from client to server are password packets
* (type 'p').
*/
do
{
mtype = pq_getbyte();
if (mtype != 'p')
{
/* Only log error if client didn't disconnect. */
if (mtype != EOF)
ereport(COMMERROR,
(errcode(ERRCODE_PROTOCOL_VIOLATION),
errmsg("expected GSS response, got message type %d",
mtype)));
return STATUS_ERROR;
}
/* Get the actual GSS token */
initStringInfo(&buf);
if (pq_getmessage(&buf, 2000))
{
/* EOF - pq_getmessage already logged error */
pfree(buf.data);
return STATUS_ERROR;
}
/* Map to GSSAPI style buffer */
gbuf.length = buf.len;
gbuf.value = buf.data;
elog(DEBUG4, "Processing received GSS token of length %u",
(unsigned int) gbuf.length);
maj_stat = gss_accept_sec_context(
&min_stat,
&port->gss->ctx,
port->gss->cred,
&gbuf,
GSS_C_NO_CHANNEL_BINDINGS,
&port->gss->name,
NULL,
&port->gss->outbuf,
&gflags,
NULL,
NULL);
/* gbuf no longer used */
pfree(buf.data);
elog(DEBUG5, "gss_accept_sec_context major: %d, "
"minor: %d, outlen: %u, outflags: %x",
maj_stat, min_stat,
(unsigned int) port->gss->outbuf.length, gflags);
if (port->gss->outbuf.length != 0)
{
/*
* Negotiation generated data to be sent to the client.
*/
OM_uint32 lmin_s;
elog(DEBUG4, "sending GSS response token of length %u",
(unsigned int) port->gss->outbuf.length);
sendAuthRequest(port, AUTH_REQ_GSS_CONT);
gss_release_buffer(&lmin_s, &port->gss->outbuf);
}
if (maj_stat != GSS_S_COMPLETE && maj_stat != GSS_S_CONTINUE_NEEDED)
{
OM_uint32 lmin_s;
gss_delete_sec_context(&lmin_s, &port->gss->ctx, GSS_C_NO_BUFFER);
pg_GSS_error(ERROR,
gettext_noop("accepting GSS security context failed"),
maj_stat, min_stat);
}
if (maj_stat == GSS_S_CONTINUE_NEEDED)
elog(DEBUG4, "GSS continue needed");
} while (maj_stat == GSS_S_CONTINUE_NEEDED);
if (port->gss->cred != GSS_C_NO_CREDENTIAL)
{
/*
* Release service principal credentials
*/
gss_release_cred(&min_stat, &port->gss->cred);
}
/*
* GSS_S_COMPLETE indicates that authentication is now complete.
*
* Get the name of the user that authenticated, and compare it to the pg
* username that was specified for the connection.
*/
maj_stat = gss_display_name(&min_stat, port->gss->name, &gbuf, NULL);
if (maj_stat != GSS_S_COMPLETE)
pg_GSS_error(ERROR,
gettext_noop("retrieving GSS user name failed"),
maj_stat, min_stat);
/*
* Split the username at the realm separator
*/
if (strchr(gbuf.value, '@'))
{
char *cp = strchr(gbuf.value, '@');
*cp = '\0';
cp++;
if (pg_krb_realm != NULL && strlen(pg_krb_realm))
{
/*
* Match the realm part of the name first
*/
if (pg_krb_caseins_users)
ret = pg_strcasecmp(pg_krb_realm, cp);
else
ret = strcmp(pg_krb_realm, cp);
if (ret)
{
/* GSS realm does not match */
elog(DEBUG2,
"GSSAPI realm (%s) and configured realm (%s) don't match",
cp, pg_krb_realm);
gss_release_buffer(&lmin_s, &gbuf);
return STATUS_ERROR;
}
}
}
else if (pg_krb_realm && strlen(pg_krb_realm))
{
elog(DEBUG2,
"GSSAPI did not return realm but realm matching was requested");
gss_release_buffer(&lmin_s, &gbuf);
return STATUS_ERROR;
}
if (pg_krb_caseins_users)
ret = pg_strcasecmp(port->user_name, gbuf.value);
else
ret = strcmp(port->user_name, gbuf.value);
if (ret)
{
/* GSS name and PGUSER are not equivalent */
elog(DEBUG2,
"provided username (%s) and GSSAPI username (%s) don't match",
port->user_name, (char *) gbuf.value);
gss_release_buffer(&lmin_s, &gbuf);
return STATUS_ERROR;
}
gss_release_buffer(&lmin_s, &gbuf);
return STATUS_OK;
}
#else /* no ENABLE_GSS */
static int
pg_GSS_recvauth(Port *port)
{
ereport(LOG,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("GSSAPI not implemented on this server")));
return STATUS_ERROR;
}
#endif /* ENABLE_GSS */
/*----------------------------------------------------------------
* SSPI authentication system
*----------------------------------------------------------------
*/
#ifdef ENABLE_SSPI
static void
pg_SSPI_error(int severity, char *errmsg, SECURITY_STATUS r)
{
char sysmsg[256];
if (FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, r, 0, sysmsg, sizeof(sysmsg), NULL) == 0)
ereport(severity,
(errmsg_internal("%s", errmsg),
errdetail("SSPI error %x", (unsigned int) r)));
else
ereport(severity,
(errmsg_internal("%s", errmsg),
errdetail("%s (%x)", sysmsg, (unsigned int) r)));
}
static int
pg_SSPI_recvauth(Port *port)
{
int mtype;
StringInfoData buf;
SECURITY_STATUS r;
CredHandle sspicred;
CtxtHandle *sspictx = NULL,
newctx;
TimeStamp expiry;
ULONG contextattr;
SecBufferDesc inbuf;
SecBufferDesc outbuf;
SecBuffer OutBuffers[1];
SecBuffer InBuffers[1];
HANDLE token;
TOKEN_USER *tokenuser;
DWORD retlen;
char accountname[MAXPGPATH];
char domainname[MAXPGPATH];
DWORD accountnamesize = sizeof(accountname);
DWORD domainnamesize = sizeof(domainname);
SID_NAME_USE accountnameuse;
HMODULE secur32;
QUERY_SECURITY_CONTEXT_TOKEN_FN _QuerySecurityContextToken;
/*
* SSPI auth is not supported for protocol versions before 3, because it
* relies on the overall message length word to determine the SSPI payload
* size in AuthenticationGSSContinue and PasswordMessage messages.
* (This is, in fact, a design error in our SSPI support, because protocol
* messages are supposed to be parsable without relying on the length
* word; but it's not worth changing it now.)
*/
if (PG_PROTOCOL_MAJOR(FrontendProtocol) < 3)
ereport(FATAL,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SSPI is not supported in protocol version 2")));
/*
* Acquire a handle to the server credentials.
*/
r = AcquireCredentialsHandle(NULL,
"negotiate",
SECPKG_CRED_INBOUND, SECPKG_CRED_INBOUND,
NULL, NULL,
NULL, NULL,
...@@ -816,391 +1236,126 @@ pg_SSPI_recvauth(Port *port) ...@@ -816,391 +1236,126 @@ pg_SSPI_recvauth(Port *port)
} while (r == SEC_I_CONTINUE_NEEDED); } while (r == SEC_I_CONTINUE_NEEDED);
/* /*
* Release service principal credentials * Release service principal credentials
*/ */
FreeCredentialsHandle(&sspicred); FreeCredentialsHandle(&sspicred);
/*
* SEC_E_OK indicates that authentication is now complete.
*
* Get the name of the user that authenticated, and compare it to the pg
* username that was specified for the connection.
*
* MingW is missing the export for QuerySecurityContextToken in the
* secur32 library, so we have to load it dynamically.
*/
secur32 = LoadLibrary("SECUR32.DLL");
if (secur32 == NULL)
ereport(ERROR,
(errmsg_internal("could not load secur32.dll: %d",
(int) GetLastError())));
_QuerySecurityContextToken = (QUERY_SECURITY_CONTEXT_TOKEN_FN)
GetProcAddress(secur32, "QuerySecurityContextToken");
if (_QuerySecurityContextToken == NULL)
{
FreeLibrary(secur32);
ereport(ERROR,
(errmsg_internal("could not locate QuerySecurityContextToken in secur32.dll: %d",
(int) GetLastError())));
}
r = (_QuerySecurityContextToken) (sspictx, &token);
if (r != SEC_E_OK)
{
FreeLibrary(secur32);
pg_SSPI_error(ERROR,
gettext_noop("could not get security token from context"), r);
}
FreeLibrary(secur32);
/*
* No longer need the security context, everything from here on uses the
* token instead.
*/
DeleteSecurityContext(sspictx);
free(sspictx);
if (!GetTokenInformation(token, TokenUser, NULL, 0, &retlen) && GetLastError() != 122)
ereport(ERROR,
(errmsg_internal("could not get token user size: error code %d",
(int) GetLastError())));
tokenuser = malloc(retlen);
if (tokenuser == NULL)
ereport(ERROR,
(errmsg("out of memory")));
if (!GetTokenInformation(token, TokenUser, tokenuser, retlen, &retlen))
ereport(ERROR,
(errmsg_internal("could not get user token: error code %d",
(int) GetLastError())));
if (!LookupAccountSid(NULL, tokenuser->User.Sid, accountname, &accountnamesize,
domainname, &domainnamesize, &accountnameuse))
ereport(ERROR,
(errmsg_internal("could not lookup acconut sid: error code %d",
(int) GetLastError())));
free(tokenuser);
/*
* Compare realm/domain if requested. In SSPI, always compare case
* insensitive.
*/
if (pg_krb_realm && strlen(pg_krb_realm))
{
if (pg_strcasecmp(pg_krb_realm, domainname))
{
elog(DEBUG2,
"SSPI domain (%s) and configured domain (%s) don't match",
domainname, pg_krb_realm);
return STATUS_ERROR;
}
}
/*
* We have the username (without domain/realm) in accountname, compare to
* the supplied value. In SSPI, always compare case insensitive.
*/
if (pg_strcasecmp(port->user_name, accountname))
{
/* GSS name and PGUSER are not equivalent */
elog(DEBUG2,
"provided username (%s) and SSPI username (%s) don't match",
port->user_name, accountname);
return STATUS_ERROR;
}
return STATUS_OK;
}
#else /* no ENABLE_SSPI */
static int
pg_SSPI_recvauth(Port *port)
{
ereport(LOG,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SSPI not implemented on this server")));
return STATUS_ERROR;
}
#endif /* ENABLE_SSPI */
/*
* Tell the user the authentication failed, but not (much about) why.
*
* There is a tradeoff here between security concerns and making life
* unnecessarily difficult for legitimate users. We would not, for example,
* want to report the password we were expecting to receive...
* But it seems useful to report the username and authorization method
* in use, and these are items that must be presumed known to an attacker
* anyway.
* Note that many sorts of failure report additional information in the
* postmaster log, which we hope is only readable by good guys.
*/
static void
auth_failed(Port *port, int status)
{
const char *errstr;
/*
* If we failed due to EOF from client, just quit; there's no point in
* trying to send a message to the client, and not much point in logging
* the failure in the postmaster log. (Logging the failure might be
* desirable, were it not for the fact that libpq closes the connection
* unceremoniously if challenged for a password when it hasn't got one to
* send. We'll get a useless log entry for every psql connection under
* password auth, even if it's perfectly successful, if we log STATUS_EOF
* events.)
*/
if (status == STATUS_EOF)
proc_exit(0);
switch (port->auth_method)
{
case uaReject:
errstr = gettext_noop("authentication failed for user \"%s\": host rejected");
break;
case uaKrb5:
errstr = gettext_noop("Kerberos 5 authentication failed for user \"%s\"");
break;
case uaGSS:
errstr = gettext_noop("GSSAPI authentication failed for user \"%s\"");
break;
case uaSSPI:
errstr = gettext_noop("SSPI authentication failed for user \"%s\"");
break;
case uaTrust:
errstr = gettext_noop("\"trust\" authentication failed for user \"%s\"");
break;
case uaIdent:
errstr = gettext_noop("Ident authentication failed for user \"%s\"");
break;
case uaMD5:
case uaCrypt:
case uaPassword:
errstr = gettext_noop("password authentication failed for user \"%s\"");
break;
#ifdef USE_PAM
case uaPAM:
errstr = gettext_noop("PAM authentication failed for user \"%s\"");
break;
#endif /* USE_PAM */
#ifdef USE_LDAP
case uaLDAP:
errstr = gettext_noop("LDAP authentication failed for user \"%s\"");
break;
#endif /* USE_LDAP */
default:
errstr = gettext_noop("authentication failed for user \"%s\": invalid authentication method");
break;
}
ereport(FATAL,
(errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
errmsg(errstr, port->user_name)));
/* doesn't return */
}
/*
* Client authentication starts here. If there is an error, this
* function does not return and the backend process is terminated.
*/
void
ClientAuthentication(Port *port)
{
int status = STATUS_ERROR;
/*
* Get the authentication method to use for this frontend/database
* combination. Note: a failure return indicates a problem with the hba
* config file, not with the request. hba.c should have dropped an error
* message into the postmaster logfile if it failed.
*/
if (hba_getauthmethod(port) != STATUS_OK)
ereport(FATAL,
(errcode(ERRCODE_CONFIG_FILE_ERROR),
errmsg("missing or erroneous pg_hba.conf file"),
errhint("See server log for details.")));
switch (port->auth_method)
{
case uaReject:
/*
* This could have come from an explicit "reject" entry in
* pg_hba.conf, but more likely it means there was no matching
* entry. Take pity on the poor user and issue a helpful error
* message. NOTE: this is not a security breach, because all the
* info reported here is known at the frontend and must be assumed
* known to bad guys. We're merely helping out the less clueful
* good guys.
*/
{
char hostinfo[NI_MAXHOST];
pg_getnameinfo_all(&port->raddr.addr, port->raddr.salen,
hostinfo, sizeof(hostinfo),
NULL, 0,
NI_NUMERICHOST);
#ifdef USE_SSL
ereport(FATAL,
(errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
errmsg("no pg_hba.conf entry for host \"%s\", user \"%s\", database \"%s\", %s",
hostinfo, port->user_name, port->database_name,
port->ssl ? _("SSL on") : _("SSL off"))));
#else
ereport(FATAL,
(errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION),
errmsg("no pg_hba.conf entry for host \"%s\", user \"%s\", database \"%s\"",
hostinfo, port->user_name, port->database_name)));
#endif
break;
}
case uaKrb5:
sendAuthRequest(port, AUTH_REQ_KRB5);
status = pg_krb5_recvauth(port);
break;
case uaGSS:
sendAuthRequest(port, AUTH_REQ_GSS);
status = pg_GSS_recvauth(port);
break;
case uaSSPI:
sendAuthRequest(port, AUTH_REQ_SSPI);
status = pg_SSPI_recvauth(port);
break;
case uaIdent:
/*
* If we are doing ident on unix-domain sockets, use SCM_CREDS
* only if it is defined and SO_PEERCRED isn't.
*/
#if !defined(HAVE_GETPEEREID) && !defined(SO_PEERCRED) && \
(defined(HAVE_STRUCT_CMSGCRED) || defined(HAVE_STRUCT_FCRED) || \
(defined(HAVE_STRUCT_SOCKCRED) && defined(LOCAL_CREDS)))
if (port->raddr.addr.ss_family == AF_UNIX)
{
#if defined(HAVE_STRUCT_FCRED) || defined(HAVE_STRUCT_SOCKCRED)
/*
* Receive credentials on next message receipt, BSD/OS,
* NetBSD. We need to set this before the client sends the
* next packet.
*/
int on = 1;
if (setsockopt(port->sock, 0, LOCAL_CREDS, &on, sizeof(on)) < 0)
ereport(FATAL,
(errcode_for_socket_access(),
errmsg("could not enable credential reception: %m")));
#endif
sendAuthRequest(port, AUTH_REQ_SCM_CREDS);
}
#endif
status = authident(port);
break;
case uaMD5:
sendAuthRequest(port, AUTH_REQ_MD5);
status = recv_and_check_password_packet(port);
break;
case uaCrypt:
sendAuthRequest(port, AUTH_REQ_CRYPT);
status = recv_and_check_password_packet(port);
break;
case uaPassword: /*
sendAuthRequest(port, AUTH_REQ_PASSWORD); * SEC_E_OK indicates that authentication is now complete.
status = recv_and_check_password_packet(port); *
break; * Get the name of the user that authenticated, and compare it to the pg
* username that was specified for the connection.
*
* MingW is missing the export for QuerySecurityContextToken in the
* secur32 library, so we have to load it dynamically.
*/
#ifdef USE_PAM secur32 = LoadLibrary("SECUR32.DLL");
case uaPAM: if (secur32 == NULL)
pam_port_cludge = port; ereport(ERROR,
status = CheckPAMAuth(port, port->user_name, ""); (errmsg_internal("could not load secur32.dll: %d",
break; (int) GetLastError())));
#endif /* USE_PAM */
#ifdef USE_LDAP _QuerySecurityContextToken = (QUERY_SECURITY_CONTEXT_TOKEN_FN)
case uaLDAP: GetProcAddress(secur32, "QuerySecurityContextToken");
status = CheckLDAPAuth(port); if (_QuerySecurityContextToken == NULL)
break; {
#endif FreeLibrary(secur32);
ereport(ERROR,
(errmsg_internal("could not locate QuerySecurityContextToken in secur32.dll: %d",
(int) GetLastError())));
}
case uaTrust: r = (_QuerySecurityContextToken) (sspictx, &token);
status = STATUS_OK; if (r != SEC_E_OK)
break; {
FreeLibrary(secur32);
pg_SSPI_error(ERROR,
gettext_noop("could not get security token from context"), r);
} }
if (status == STATUS_OK) FreeLibrary(secur32);
sendAuthRequest(port, AUTH_REQ_OK);
else
auth_failed(port, status);
}
/*
* No longer need the security context, everything from here on uses the
* token instead.
*/
DeleteSecurityContext(sspictx);
free(sspictx);
/* if (!GetTokenInformation(token, TokenUser, NULL, 0, &retlen) && GetLastError() != 122)
* Send an authentication request packet to the frontend. ereport(ERROR,
*/ (errmsg_internal("could not get token user size: error code %d",
static void (int) GetLastError())));
sendAuthRequest(Port *port, AuthRequest areq)
{
StringInfoData buf;
pq_beginmessage(&buf, 'R'); tokenuser = malloc(retlen);
pq_sendint(&buf, (int32) areq, sizeof(int32)); if (tokenuser == NULL)
ereport(ERROR,
(errmsg("out of memory")));
/* Add the salt for encrypted passwords. */ if (!GetTokenInformation(token, TokenUser, tokenuser, retlen, &retlen))
if (areq == AUTH_REQ_MD5) ereport(ERROR,
pq_sendbytes(&buf, port->md5Salt, 4); (errmsg_internal("could not get user token: error code %d",
else if (areq == AUTH_REQ_CRYPT) (int) GetLastError())));
pq_sendbytes(&buf, port->cryptSalt, 2);
#if defined(ENABLE_GSS) || defined(ENABLE_SSPI) if (!LookupAccountSid(NULL, tokenuser->User.Sid, accountname, &accountnamesize,
domainname, &domainnamesize, &accountnameuse))
ereport(ERROR,
(errmsg_internal("could not lookup acconut sid: error code %d",
(int) GetLastError())));
free(tokenuser);
/* /*
* Add the authentication data for the next step of the GSSAPI or SSPI * Compare realm/domain if requested. In SSPI, always compare case
* negotiation. * insensitive.
*/ */
else if (areq == AUTH_REQ_GSS_CONT) if (pg_krb_realm && strlen(pg_krb_realm))
{ {
if (port->gss->outbuf.length > 0) if (pg_strcasecmp(pg_krb_realm, domainname))
{ {
elog(DEBUG4, "sending GSS token of length %u", elog(DEBUG2,
(unsigned int) port->gss->outbuf.length); "SSPI domain (%s) and configured domain (%s) don't match",
domainname, pg_krb_realm);
pq_sendbytes(&buf, port->gss->outbuf.value, port->gss->outbuf.length); return STATUS_ERROR;
} }
} }
#endif
pq_endmessage(&buf);
/* /*
* Flush message so client will see it, except for AUTH_REQ_OK, which need * We have the username (without domain/realm) in accountname, compare to
* not be sent until we are ready for queries. * the supplied value. In SSPI, always compare case insensitive.
*/ */
if (areq != AUTH_REQ_OK) if (pg_strcasecmp(port->user_name, accountname))
pq_flush(); {
/* GSS name and PGUSER are not equivalent */
elog(DEBUG2,
"provided username (%s) and SSPI username (%s) don't match",
port->user_name, accountname);
return STATUS_ERROR;
}
return STATUS_OK;
}
#else /* no ENABLE_SSPI */
static int
pg_SSPI_recvauth(Port *port)
{
ereport(LOG,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("SSPI not implemented on this server")));
return STATUS_ERROR;
} }
#endif /* ENABLE_SSPI */
/*---------------------------------------------------------------- /*----------------------------------------------------------------
* Ident authentication system * Ident authentication system
*---------------------------------------------------------------- *----------------------------------------------------------------
...@@ -1655,7 +1810,6 @@ authident(hbaPort *port) ...@@ -1655,7 +1810,6 @@ authident(hbaPort *port)
* PAM authentication system * PAM authentication system
*---------------------------------------------------------------- *----------------------------------------------------------------
*/ */
#ifdef USE_PAM #ifdef USE_PAM
/* /*
...@@ -1835,6 +1989,11 @@ CheckPAMAuth(Port *port, char *user, char *password) ...@@ -1835,6 +1989,11 @@ CheckPAMAuth(Port *port, char *user, char *password)
#endif /* USE_PAM */ #endif /* USE_PAM */
/*----------------------------------------------------------------
* LDAP authentication system
*----------------------------------------------------------------
*/
#ifdef USE_LDAP #ifdef USE_LDAP
static int static int
...@@ -2014,94 +2173,3 @@ CheckLDAPAuth(Port *port) ...@@ -2014,94 +2173,3 @@ CheckLDAPAuth(Port *port)
} }
#endif /* USE_LDAP */ #endif /* USE_LDAP */
/*
* Collect password response packet from frontend.
*
* Returns NULL if couldn't get password, else palloc'd string.
*/
static char *
recv_password_packet(Port *port)
{
StringInfoData buf;
if (PG_PROTOCOL_MAJOR(port->proto) >= 3)
{
/* Expect 'p' message type */
int mtype;
mtype = pq_getbyte();
if (mtype != 'p')
{
/*
* If the client just disconnects without offering a password,
* don't make a log entry. This is legal per protocol spec and in
* fact commonly done by psql, so complaining just clutters the
* log.
*/
if (mtype != EOF)
ereport(COMMERROR,
(errcode(ERRCODE_PROTOCOL_VIOLATION),
errmsg("expected password response, got message type %d",
mtype)));
return NULL; /* EOF or bad message type */
}
}
else
{
/* For pre-3.0 clients, avoid log entry if they just disconnect */
if (pq_peekbyte() == EOF)
return NULL; /* EOF */
}
initStringInfo(&buf);
if (pq_getmessage(&buf, 1000)) /* receive password */
{
/* EOF - pq_getmessage already logged a suitable message */
pfree(buf.data);
return NULL;
}
/*
* Apply sanity check: password packet length should agree with length of
* contained string. Note it is safe to use strlen here because
* StringInfo is guaranteed to have an appended '\0'.
*/
if (strlen(buf.data) + 1 != buf.len)
ereport(COMMERROR,
(errcode(ERRCODE_PROTOCOL_VIOLATION),
errmsg("invalid password packet size")));
/* Do not echo password to logs, for security. */
ereport(DEBUG5,
(errmsg("received password packet")));
/*
* Return the received string. Note we do not attempt to do any
* character-set conversion on it; since we don't yet know the client's
* encoding, there wouldn't be much point.
*/
return buf.data;
}
/*
* Called when we have sent an authorization request for a password.
* Get the response and check it.
*/
static int
recv_and_check_password_packet(Port *port)
{
char *passwd;
int result;
passwd = recv_password_packet(port);
if (passwd == NULL)
return STATUS_EOF; /* client wouldn't send password */
result = md5_crypt_verify(port, port->user_name, passwd);
pfree(passwd);
return result;
}
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