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Add SCM_CREDS to get owner of unix-domain socket on BSD-like systems.
1 parent 04fdf73 commit bca9d0c

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9 files changed

+1019
-783
lines changed

9 files changed

+1019
-783
lines changed

‎doc/FAQ_japanese

Lines changed: 701 additions & 653 deletions
Large diffs are not rendered by default.

‎doc/src/FAQ/FAQ_japanese.html

Lines changed: 125 additions & 104 deletions
Large diffs are not rendered by default.

‎src/backend/libpq/auth.c

Lines changed: 29 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -8,17 +8,22 @@
88
*
99
*
1010
* IDENTIFICATION
11-
* $Header: /cvsroot/pgsql/src/backend/libpq/auth.c,v 1.62 2001/08/17 15:44:17 momjian Exp $
11+
* $Header: /cvsroot/pgsql/src/backend/libpq/auth.c,v 1.63 2001/08/21 00:33:27 momjian Exp $
1212
*
1313
*-------------------------------------------------------------------------
1414
*/
1515

1616
#include "postgres.h"
1717

18-
#include <sys/types.h> /* needed by in.h on Ultrix */
18+
#include <sys/types.h>
19+
#include <sys/socket.h> /* for SCM_CREDS */
20+
#ifdef SCM_CREDS
21+
#include <sys/uio.h> /* for struct iovec */
22+
#include <sys/ucred.h>
23+
#include <errno.h>
24+
#endif
1925
#include <netinet/in.h>
2026
#include <arpa/inet.h>
21-
2227
#include "libpq/auth.h"
2328
#include "libpq/crypt.h"
2429
#include "libpq/hba.h"
@@ -28,12 +33,10 @@
2833
#include "miscadmin.h"
2934

3035
static void sendAuthRequest(Port *port, AuthRequest areq);
31-
3236
static int checkPassword(Port *port, char *user, char *password);
3337
static int old_be_recvauth(Port *port);
3438
static int map_old_to_new(Port *port, UserAuth old, int status);
3539
static void auth_failed(Port *port);
36-
3740
static int recv_and_check_password_packet(Port *port);
3841
static int recv_and_check_passwordv0(Port *port);
3942

@@ -493,6 +496,26 @@ ClientAuthentication(Port *port)
493496
break;
494497

495498
case uaIdent:
499+
#if !defined(SO_PEERCRED) && defined(SCM_CREDS)
500+
/*
501+
* If we are doing ident on unix-domain sockets,
502+
* use SCM_CREDS only if it is defined and SO_PEERCRED isn't.
503+
*/
504+
#ifdef fc_uid
505+
/* Receive credentials on next message receipt, BSD/OS */
506+
{
507+
int on = 1;
508+
if (setsockopt(port->sock, 0, LOCAL_CREDS, &on, sizeof(on)) < 0)
509+
{
510+
elog(FATAL,
511+
"pg_local_sendauth: can't do setsockopt: %s\n", strerror(errno));
512+
return;
513+
}
514+
}
515+
#endif
516+
if (port->raddr.sa.sa_family == AF_UNIX)
517+
sendAuthRequest(port, AUTH_REQ_SCM_CREDS);
518+
#endif
496519
status = authident(port);
497520
break;
498521

@@ -676,3 +699,4 @@ map_old_to_new(Port *port, UserAuth old, int status)
676699

677700
return status;
678701
}
702+

‎src/backend/libpq/hba.c

Lines changed: 79 additions & 11 deletions
Original file line numberDiff line numberDiff line change
@@ -10,17 +10,21 @@
1010
*
1111
*
1212
* IDENTIFICATION
13-
* $Header: /cvsroot/pgsql/src/backend/libpq/hba.c,v 1.64 2001/08/16 16:24:15 momjian Exp $
13+
* $Header: /cvsroot/pgsql/src/backend/libpq/hba.c,v 1.65 2001/08/21 00:33:27 momjian Exp $
1414
*
1515
*-------------------------------------------------------------------------
1616
*/
1717
#include "postgres.h"
1818

1919
#include <errno.h>
2020
#include <pwd.h>
21-
#include <sys/types.h>
2221
#include <fcntl.h>
23-
#include <sys/socket.h>
22+
#include <sys/types.h>
23+
#include <sys/socket.h> /* for SCM_CREDS */
24+
#ifdef SCM_CREDS
25+
#include <sys/uio.h> /* for struct iovec */
26+
#include <sys/ucred.h>
27+
#endif
2428
#include <netinet/in.h>
2529
#include <arpa/inet.h>
2630
#include <unistd.h>
@@ -876,39 +880,103 @@ ident_unix(int sock, char *ident_user)
876880
{
877881
/* We didn't get a valid credentials struct. */
878882
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
879-
"Could not get valid credentials from the UNIX socket: %s\n",
883+
"ident_unix: error receiving credentials: %s\n",
880884
strerror(errno));
881885
fputs(PQerrormsg, stderr);
882886
pqdebug("%s", PQerrormsg);
883887
return false;
884888
}
885889

886-
/* Convert UID to user login name */
887890
pass = getpwuid(peercred.uid);
888891

889892
if (pass == NULL)
890893
{
891-
/* Error - no username with the given uid */
892894
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
893-
"There is no entry in /etc/passwd with the socket's uid\n");
895+
"ident_unix: unknown local user with uid %d\n",
894896
fputs(PQerrormsg, stderr);
895897
pqdebug("%s", PQerrormsg);
896898
return false;
897899
}
898900

899-
StrNCpy(ident_user, pass->pw_name, IDENT_USERNAME_MAX);
901+
StrNCpy(ident_user, pass->pw_name, IDENT_USERNAME_MAX+1);
900902

901903
return true;
902904

903-
#else /* not SO_PEERCRED */
905+
#elif defined(SCM_CREDS)
906+
struct msghdr msg;
907+
908+
/* Credentials structure */
909+
#ifndef fc_uid
910+
typedef struct cmsgcred Cred;
911+
#define cruid cmcred_uid
912+
#else
913+
typedef struct fcred Cred;
914+
#define cruid fc_uid
915+
#endif
916+
Cred *cred;
917+
918+
/* Compute size without padding */
919+
char cmsgmem[sizeof(struct cmsghdr) + sizeof(Cred)];
920+
/* Point to start of first structure */
921+
struct cmsghdr *cmsg = (struct cmsghdr *)cmsgmem;
922+
923+
struct iovec iov;
924+
char buf;
925+
struct passwd *pw;
926+
927+
memset(&msg, 0, sizeof(msg));
928+
msg.msg_iov = &iov;
929+
msg.msg_iovlen = 1;
930+
msg.msg_control = (char *)cmsg;
931+
msg.msg_controllen = sizeof(cmsgmem);
932+
memset(cmsg, 0, sizeof(cmsgmem));
933+
934+
/*
935+
* The one character which is received here is not meaningful;
936+
* its purposes is only to make sure that recvmsg() blocks
937+
* long enough for the other side to send its credentials.
938+
*/
939+
iov.iov_base = &buf;
940+
iov.iov_len = 1;
941+
942+
if (recvmsg(sock, &msg, 0) < 0 ||
943+
cmsg->cmsg_len < sizeof(cmsgmem) ||
944+
cmsg->cmsg_type != SCM_CREDS)
945+
{
946+
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
947+
"ident_unix: error receiving credentials: %s\n",
948+
strerror(errno));
949+
fputs(PQerrormsg, stderr);
950+
pqdebug("%s", PQerrormsg);
951+
return false;
952+
}
953+
954+
cred = (Cred *)CMSG_DATA(cmsg);
904955

956+
pw = getpwuid(cred->fc_uid);
957+
if (pw == NULL)
958+
{
959+
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
960+
"ident_unix: unknown local user with uid %d\n",
961+
cred->fc_uid);
962+
fputs(PQerrormsg, stderr);
963+
pqdebug("%s", PQerrormsg);
964+
return false;
965+
}
966+
967+
StrNCpy(ident_user, pw->pw_name, IDENT_USERNAME_MAX+1);
968+
969+
return true;
970+
971+
#else
905972
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
906-
"IDENT auth is not supported on local connections on this platform\n");
973+
"'ident' auth is not supported on local connections on this platform\n");
907974
fputs(PQerrormsg, stderr);
908975
pqdebug("%s", PQerrormsg);
976+
909977
return false;
910978

911-
#endif /* SO_PEERCRED */
979+
#endif
912980
}
913981

914982
/*

‎src/backend/libpq/pg_hba.conf.sample

Lines changed: 6 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -127,12 +127,12 @@
127127
# ident: For TCP/IP connections, authentication is done by contacting
128128
# the ident server on the client host. (CAUTION: this is only
129129
# as secure as the client machine!) On machines that support
130-
# SO_PEERCRED socket requests, this method also works for
131-
# local Unix-domain connections. AUTH_ARGUMENT is required:
132-
# it determines how to map remote user names to Postgres user
133-
# names. The AUTH_ARGUMENT is a map name found in the
134-
# $PGDATA/pg_ident.conf file. The connection is accepted if
135-
# that file contains an entry for this map name with the
130+
# SO_PEERCRED or SCM_CREDS socket requests, this method also
131+
# works for local Unix-domain connections. AUTH_ARGUMENT is
132+
# required: it determines how to map remote user names to
133+
# Postgres user names. The AUTH_ARGUMENT is a map name found
134+
# in the $PGDATA/pg_ident.conf file. The connection is accepted
135+
# if that file contains an entry for this map name with the
136136
# ident-supplied username and the requested Postgres username.
137137
# The special map name "sameuser" indicates an implied map
138138
# (not in pg_ident.conf) that maps each ident username to the

‎src/include/libpq/pqcomm.h

Lines changed: 2 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -9,7 +9,7 @@
99
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
1010
* Portions Copyright (c) 1994, Regents of the University of California
1111
*
12-
* $Id: pqcomm.h,v 1.57 2001/08/16 04:27:18 momjian Exp $
12+
* $Id: pqcomm.h,v 1.58 2001/08/21 00:33:27 momjian Exp $
1313
*
1414
*-------------------------------------------------------------------------
1515
*/
@@ -133,6 +133,7 @@ typedef struct StartupPacket
133133
#define AUTH_REQ_PASSWORD 3 /* Password */
134134
#define AUTH_REQ_CRYPT 4 /* crypt password */
135135
#define AUTH_REQ_MD5 5 /* md5 password */
136+
#define AUTH_REQ_SCM_CREDS 6 /* transfer SCM credentials */
136137

137138
typedef uint32 AuthRequest;
138139

‎src/interfaces/libpq/fe-auth.c

Lines changed: 71 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -10,7 +10,7 @@
1010
* exceed INITIAL_EXPBUFFER_SIZE (currently 256 bytes).
1111
*
1212
* IDENTIFICATION
13-
* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-auth.c,v 1.55 2001/08/17 15:40:07 momjian Exp $
13+
* $Header: /cvsroot/pgsql/src/interfaces/libpq/fe-auth.c,v 1.56 2001/08/21 00:33:27 momjian Exp $
1414
*
1515
*-------------------------------------------------------------------------
1616
*/
@@ -30,6 +30,7 @@
3030

3131
#include "postgres_fe.h"
3232

33+
/* XXX is there a reason these appear before the system defines? */
3334
#include "libpq-fe.h"
3435
#include "libpq-int.h"
3536
#include "fe-auth.h"
@@ -40,6 +41,13 @@
4041
#else
4142
#include <unistd.h>
4243
#include <fcntl.h>
44+
#include <errno.h>
45+
#include <sys/types.h>
46+
#include <sys/socket.h> /* for SCM_CREDS */
47+
#ifdef SCM_CREDS
48+
#include <sys/uio.h> /* for struct iovec */
49+
#include <sys/ucred.h>
50+
#endif
4351
#include <sys/param.h> /* for MAXHOSTNAMELEN on most */
4452
#ifndef MAXHOSTNAMELEN
4553
#include <netdb.h> /* for MAXHOSTNAMELEN on some */
@@ -428,6 +436,53 @@ pg_krb5_sendauth(char *PQerrormsg, int sock,
428436

429437
#endif /* KRB5 */
430438

439+
#ifdef SCM_CREDS
440+
static int
441+
pg_local_sendauth(char *PQerrormsg, PGconn *conn)
442+
{
443+
char buf;
444+
struct iovec iov;
445+
struct msghdr msg;
446+
#ifndef fc_uid
447+
/* Prevent padding */
448+
char cmsgmem[sizeof(struct cmsghdr) + sizeof(struct cmsgcred)];
449+
/* Point to start of first structure */
450+
struct cmsghdr *cmsg = (struct cmsghdr *)cmsgmem;
451+
#endif
452+
453+
/*
454+
* The backend doesn't care what we send here, but it wants
455+
* exactly one character to force recvmsg() to block and wait
456+
* for us.
457+
*/
458+
buf = '\0';
459+
iov.iov_base = &buf;
460+
iov.iov_len = 1;
461+
462+
memset(&msg, 0, sizeof(msg));
463+
msg.msg_iov = &iov;
464+
msg.msg_iovlen = 1;
465+
466+
#ifndef fc_uid
467+
/* Create control header, FreeBSD */
468+
msg.msg_control = cmsg;
469+
msg.msg_controllen = sizeof(cmsgmem);
470+
memset(cmsg, 0, sizeof(cmsgmem));
471+
cmsg.hdr.cmsg_len = sizeof(cmsgmem);
472+
cmsg.hdr.cmsg_level = SOL_SOCKET;
473+
cmsg.hdr.cmsg_type = SCM_CREDS;
474+
#endif
475+
476+
if (sendmsg(conn->sock, &msg, 0) == -1)
477+
{
478+
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
479+
"pg_local_sendauth: sendmsg: %s\n", strerror(errno));
480+
return STATUS_ERROR;
481+
}
482+
return STATUS_OK;
483+
}
484+
#endif
485+
431486
static int
432487
pg_password_sendauth(PGconn *conn, const char *password, AuthRequest areq)
433488
{
@@ -473,12 +528,13 @@ pg_password_sendauth(PGconn *conn, const char *password, AuthRequest areq)
473528
crypt_pwd = crypt(password, salt);
474529
break;
475530
}
476-
default:
531+
case AUTH_REQ_PASSWORD:
477532
/* discard const so we can assign it */
478533
crypt_pwd = (char *)password;
479534
break;
535+
default:
536+
return STATUS_ERROR;
480537
}
481-
482538
ret = pqPacketSend(conn, crypt_pwd, strlen(crypt_pwd) + 1);
483539
if (areq == AUTH_REQ_MD5)
484540
free(crypt_pwd);
@@ -551,6 +607,18 @@ fe_sendauth(AuthRequest areq, PGconn *conn, const char *hostname,
551607
return STATUS_ERROR;
552608
}
553609
break;
610+
611+
case AUTH_REQ_SCM_CREDS:
612+
#ifdef SCM_CREDS
613+
if (pg_local_sendauth(PQerrormsg, conn) != STATUS_OK)
614+
return STATUS_ERROR;
615+
#else
616+
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
617+
libpq_gettext("SCM_CRED authentication method not supported\n"));
618+
return STATUS_ERROR;
619+
#endif
620+
break;
621+
554622
default:
555623
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
556624
libpq_gettext("authentication method %u not supported\n"), areq);

‎src/interfaces/odbc/connection.c

Lines changed: 5 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -726,6 +726,11 @@ CC_connect(ConnectionClass *self, char do_password)
726726
self->errornumber = CONN_AUTH_TYPE_UNSUPPORTED;
727727
return 0;
728728

729+
case AUTH_REQ_SCM_CREDS:
730+
self->errormsg = "Unix socket credential authentication not supported";
731+
self->errornumber = CONN_AUTH_TYPE_UNSUPPORTED;
732+
return 0;
733+
729734
default:
730735
self->errormsg = "Unknown authentication type";
731736
self->errornumber = CONN_AUTH_TYPE_UNSUPPORTED;

‎src/interfaces/odbc/connection.h

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -94,6 +94,7 @@ typedef enum
9494
#define AUTH_REQ_PASSWORD 3
9595
#define AUTH_REQ_CRYPT 4
9696
#define AUTH_REQ_MD5 5
97+
#define AUTH_REQ_SCM_CREDS 6
9798

9899
/* Startup Packet sizes */
99100
#define SM_DATABASE 64

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