Revert "Add better checks on PAM socket"

This reverts commit ff019cfb5d083a152361ec9ce3f233211ff3907a.

4 files changed, 5 insertions, 266 deletions

diff --git a/src/external/platform.m4 b/src/external/platform.m4
index ee0093789..71b4f2c85 100644
--- a/src/external/platform.m4
+++ b/src/external/platform.m4
@@ -27,15 +27,3 @@ fi
 AM_CONDITIONAL([HAVE_FEDORA], [test x"$osname" == xfedora])
 AM_CONDITIONAL([HAVE_REDHAT], [test x"$osname" == xredhat])
 AM_CONDITIONAL([HAVE_SUSE], [test x"$osname" == xsuse])
-
-AC_CHECK_MEMBERS([struct ucred.pid, struct ucred.uid, struct ucred.gid], , ,
-                 [[#define _GNU_SOURCE
-                   #include <sys/socket.h>]])
-
-if test x"$ac_cv_member_struct_ucred_pid" = xyes -a \
-        x"$ac_cv_member_struct_ucred_uid" = xyes -a \
-        x"$ac_cv_member_struct_ucred_gid" = xyes ; then
-    AC_DEFINE([HAVE_UCRED], [1], [Define if struct ucred is available])
-else
-    AC_MSG_WARN([struct ucred is not available])
-fi
diff --git a/src/responder/common/responder.h b/src/responder/common/responder.h
index 6391fcf7c..ea6ba5831 100644
--- a/src/responder/common/responder.h
+++ b/src/responder/common/responder.h
@@ -101,10 +101,6 @@ struct cli_ctx {
     struct cli_request *creq;
     struct cli_protocol_version *cli_protocol_version;
     int priv;
-    int creds_exchange_done;
-    int client_uid;
-    int client_gid;
-    int client_pid;
 };
 
 struct sss_cmd_table {
diff --git a/src/responder/common/responder_common.c b/src/responder/common/responder_common.c
index f4de3a79e..f524afb93 100644
--- a/src/responder/common/responder_common.c
+++ b/src/responder/common/responder_common.c
@@ -19,9 +19,6 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-/* for struct ucred */
-#define _GNU_SOURCE
-
 #include <stdio.h>
 #include <unistd.h>
 #include <fcntl.h>
@@ -32,8 +29,7 @@
 #include <string.h>
 #include <sys/time.h>
 #include <errno.h>
-#include <popt.h>
-#include "config.h"
+#include "popt.h"
 #include "util/util.h"
 #include "db/sysdb.h"
 #include "confdb/confdb.h"
@@ -148,130 +144,12 @@ static void client_recv(struct tevent_context *ev, struct cli_ctx *cctx)
     return;
 }
 
-static void cred_handler(struct cli_ctx *cctx, char action)
-{
-#ifdef HAVE_UCRED
-    int ret;
-    int fd;
-    struct msghdr msg;
-    struct iovec iov;
-    struct cmsghdr *cmsg;
-    struct ucred *creds;
-    char buf[CMSG_SPACE(sizeof(struct ucred))];
-    char dummy='s';
-    int enable=1;
-
-    if (cctx->creds_exchange_done != 0) {
-        DEBUG(1, ("cred_handler called, but creds are already exchanged.\n"));
-        goto failed;
-    }
-
-    fd = cctx->cfd;
-
-    iov.iov_base = &dummy;
-    iov.iov_len = 1;
-
-    memset (&msg, 0, sizeof(msg));
-
-    msg.msg_name = NULL;
-    msg.msg_namelen = 0;
-    msg.msg_iov = &iov;
-    msg.msg_iovlen = 1;
-
-    msg.msg_control = buf;
-    msg.msg_controllen = sizeof(buf);
-
-    switch (action) {
-        case 'r':
-            ret = setsockopt(fd, SOL_SOCKET, SO_PASSCRED, &enable, sizeof(int));
-            if (ret == -1) {
-                DEBUG(1, ("setsockopt failed: [%d][%s].\n", errno,
-                                                            strerror(errno)));
-                goto failed;
-            }
-
-            ret = recvmsg(fd, &msg, 0);
-            if (ret == -1) {
-                DEBUG(1, ("recvmsg failed.[%d][%s]\n", errno, strerror(errno)));
-                goto failed;
-            }
-
-            cmsg = CMSG_FIRSTHDR(&msg);
-
-            if (cmsg->cmsg_level == SOL_SOCKET &&
-                cmsg->cmsg_type == SCM_CREDENTIALS) {
-                creds = (struct ucred *) CMSG_DATA(cmsg);
-                DEBUG(1, ("creds: [%d][%d][%d]\n",creds->uid, creds->gid,
-                                                  creds->pid));
-                cctx->client_uid = creds->uid;
-                cctx->client_gid = creds->gid;
-                cctx->client_pid = creds->pid;
-            }
-
-            TEVENT_FD_WRITEABLE(cctx->cfde);
-
-            return;
-            break;
-        case 's':
-            cmsg = CMSG_FIRSTHDR(&msg);
-            cmsg->cmsg_level = SOL_SOCKET;
-            cmsg->cmsg_type = SCM_CREDENTIALS;
-            cmsg->cmsg_len = CMSG_LEN(sizeof(struct ucred));
-
-            creds = (struct ucred *) CMSG_DATA(cmsg);
-
-            creds->uid = geteuid();
-            creds->gid = getegid();
-            creds->pid = getpid();
-
-            msg.msg_controllen = cmsg->cmsg_len;
-
-            ret = sendmsg(fd, &msg, 0);
-            if (ret == -1) {
-                DEBUG(1, ("sendmsg failed.[%d][%s]\n", errno, strerror(errno)));
-                goto failed;
-            }
-            DEBUG(4, ("Send creds to the client succesfully.\n"));
-            cctx->creds_exchange_done = 1;
-
-            TEVENT_FD_NOT_WRITEABLE(cctx->cfde);
-            return;
-        default:
-            DEBUG(1, ("Unknown action [%c].\n", action));
-            goto failed;
-    }
-
-failed:
-    talloc_free(cctx);
-    return;
-
-#else
-
-    DEBUG(9, ("Credential exchange not available over socket, "
-              "continuing without.\n"));
-    cctx->creds_exchange_done = 1;
-    return;
-
-#endif
-}
-
 static void client_fd_handler(struct tevent_context *ev,
                               struct tevent_fd *fde,
                               uint16_t flags, void *ptr)
 {
     struct cli_ctx *cctx = talloc_get_type(ptr, struct cli_ctx);
 
-    if (cctx->creds_exchange_done == 0) {
-        if (flags & TEVENT_FD_READ) {
-            cred_handler(cctx, 'r');
-            return;
-        }
-        if (flags & TEVENT_FD_WRITE) {
-            cred_handler(cctx, 's');
-            return;
-        }
-    }
-
     if (flags & TEVENT_FD_READ) {
         client_recv(ev, cctx);
         return;
@@ -335,10 +213,6 @@ static void accept_priv_fd_handler(struct tevent_context *ev,
     }
 
     cctx->priv = 1;
-    cctx->creds_exchange_done = 0;
-    cctx->client_uid = -1;
-    cctx->client_gid = -1;
-    cctx->client_pid = -1;
 
     cctx->cfde = tevent_add_fd(ev, cctx, cctx->cfd,
                                TEVENT_FD_READ, client_fd_handler, cctx);
@@ -391,11 +265,6 @@ static void accept_fd_handler(struct tevent_context *ev,
         return;
     }
 
-    cctx->creds_exchange_done = 0;
-    cctx->client_uid = -1;
-    cctx->client_gid = -1;
-    cctx->client_pid = -1;
-
     cctx->cfde = tevent_add_fd(ev, cctx, cctx->cfd,
                                TEVENT_FD_READ, client_fd_handler, cctx);
     if (!cctx->cfde) {
diff --git a/src/sss_client/common.c b/src/sss_client/common.c
index f1c8d1853..6732c24fc 100644
--- a/src/sss_client/common.c
+++ b/src/sss_client/common.c
@@ -23,9 +23,6 @@
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-/* for struct ucred */
-#define _GNU_SOURCE
-
 #include <nss.h>
 #include <security/pam_modules.h>
 #include <errno.h>
@@ -39,8 +36,6 @@
 #include <string.h>
 #include <fcntl.h>
 #include <poll.h>
-
-#include "config.h"
 #include "sss_cli.h"
 
 /* common functions */
@@ -55,104 +50,6 @@ static void sss_cli_close_socket(void)
     }
 }
 
-static int exchange_credentials(void)
-{
-#ifdef HAVE_UCRED
-    int ret;
-    struct msghdr msg;
-    struct cmsghdr *cmsg;
-    struct iovec iov;
-    char dummy='a';
-    char buf[CMSG_SPACE(sizeof(struct ucred))];
-    struct ucred *creds;
-    int enable = 1;
-    struct pollfd pfd;
-
-    ret = setsockopt(sss_cli_sd, SOL_SOCKET, SO_PASSCRED, &enable, sizeof(int));
-    if (ret == -1) {
-        return errno;
-    }
-
-    iov.iov_base = &dummy;
-    iov.iov_len = 1;
-
-    memset(&msg, 0, sizeof(msg));
-
-    msg.msg_name = NULL;
-    msg.msg_namelen = 0;
-    msg.msg_iov = &iov;
-    msg.msg_iovlen = 1;
-
-    msg.msg_control = buf;
-    msg.msg_controllen = sizeof(buf);
-
-    cmsg = CMSG_FIRSTHDR(&msg);
-    cmsg->cmsg_level = SOL_SOCKET;
-    cmsg->cmsg_type = SCM_CREDENTIALS;
-    cmsg->cmsg_len = CMSG_LEN(sizeof(struct ucred));
-
-    creds = (struct ucred *) CMSG_DATA(cmsg);
-
-    creds->uid = geteuid();
-    creds->gid = getegid();
-    creds->pid = getpid();
-
-    msg.msg_controllen = cmsg->cmsg_len;
-
-    pfd.fd = sss_cli_sd;
-    pfd.events = POLLOUT;
-    ret = poll(&pfd, 1, SSS_CLI_SOCKET_TIMEOUT);
-    if (ret != 1 || !(pfd.revents & POLLOUT) ) {
-        return errno;
-    }
-
-    ret = sendmsg(sss_cli_sd, &msg, 0);
-    if (ret == -1) {
-        return errno;
-    }
-
-    memset(&msg, 0, sizeof(msg));
-
-    msg.msg_name = NULL;
-    msg.msg_namelen = 0;
-    msg.msg_iov = &iov;
-    msg.msg_iovlen = 1;
-
-    msg.msg_control = buf;
-    msg.msg_controllen = sizeof(buf);
-
-    pfd.fd = sss_cli_sd;
-    pfd.events = POLLIN;
-    ret = poll(&pfd, 1, SSS_CLI_SOCKET_TIMEOUT);
-
-    if (ret != 1 || !(pfd.revents & POLLIN) ) {
-        return errno;
-    }
-
-    ret = recvmsg(sss_cli_sd, &msg, 0);
-    if (ret == -1) {
-        return errno;
-    }
-
-    cmsg = CMSG_FIRSTHDR(&msg);
-
-    if (msg.msg_controllen != 0 && cmsg->cmsg_level == SOL_SOCKET &&
-                                   cmsg->cmsg_type == SCM_CREDENTIALS) {
-        creds = (struct ucred *) CMSG_DATA(cmsg);
-        if (creds->uid != 0 || creds->gid!= 0) {
-            return SSS_STATUS_UNAVAIL;
-        }
-    }
-
-    return SSS_STATUS_SUCCESS;
-
-#else
-
-    return SSS_STATUS_SUCCESS;
-
-#endif
-}
-
 /* Requests:
  *
  * byte 0-3: 32bit unsigned with length (the complete packet length: 0 to X)
@@ -702,10 +599,9 @@ static enum sss_status sss_cli_check_socket(int *errnop, const char *socket_name
 
     sss_cli_sd = mysd;
 
-    if (exchange_credentials() == SSS_STATUS_SUCCESS)
-        if (sss_nss_check_version(socket_name) == NSS_STATUS_SUCCESS) {
-            return SSS_STATUS_SUCCESS;
-        }
+    if (sss_nss_check_version(socket_name) == NSS_STATUS_SUCCESS) {
+        return SSS_STATUS_SUCCESS;
+    }
 
     sss_cli_close_socket();
     *errnop = EFAULT;
@@ -757,22 +653,12 @@ int sss_pam_make_request(enum sss_cli_command cmd,
         if (ret != 0) return PAM_SERVICE_ERR;
         if ( ! (stat_buf.st_uid == 0 &&
                 stat_buf.st_gid == 0 &&
-                S_ISSOCK(stat_buf.st_mode) &&
-                (stat_buf.st_mode & ~S_IFMT) == 0600 )) {
+                (stat_buf.st_mode&(S_IFSOCK|S_IRUSR|S_IWUSR)) == stat_buf.st_mode)) {
             return PAM_SERVICE_ERR;
         }
 
         ret = sss_cli_check_socket(errnop, SSS_PAM_PRIV_SOCKET_NAME);
     } else {
-        ret = stat(SSS_PAM_SOCKET_NAME, &stat_buf);
-        if (ret != 0) return PAM_SERVICE_ERR;
-        if ( ! (stat_buf.st_uid == 0 &&
-                stat_buf.st_gid == 0 &&
-                S_ISSOCK(stat_buf.st_mode) &&
-                (stat_buf.st_mode & ~S_IFMT) == 0666 )) {
-            return PAM_SERVICE_ERR;
-        }
-
         ret = sss_cli_check_socket(errnop, SSS_PAM_SOCKET_NAME);
     }
     if (ret != NSS_STATUS_SUCCESS) {