From patchwork Tue Sep 8 23:17:37 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Zhou X-Patchwork-Id: 515637 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from archives.nicira.com (unknown [IPv6:2600:3c00::f03c:91ff:fe6e:bdf7]) by ozlabs.org (Postfix) with ESMTP id 11CBC140180 for ; Wed, 9 Sep 2015 09:17:59 +1000 (AEST) Received: from archives.nicira.com (localhost [127.0.0.1]) by archives.nicira.com (Postfix) with ESMTP id 30044106BC; Tue, 8 Sep 2015 16:17:50 -0700 (PDT) X-Original-To: dev@openvswitch.org Delivered-To: dev@openvswitch.org Received: from mx1e4.cudamail.com (mx1.cudamail.com [69.90.118.67]) by archives.nicira.com (Postfix) with ESMTPS id 11357106B4 for ; Tue, 8 Sep 2015 16:17:49 -0700 (PDT) Received: from bar5.cudamail.com (unknown [192.168.21.12]) by mx1e4.cudamail.com (Postfix) with ESMTPS id 775541E024B for ; Tue, 8 Sep 2015 17:17:48 -0600 (MDT) X-ASG-Debug-ID: 1441754265-09eadd7da4b4360001-byXFYA Received: from mx1-pf2.cudamail.com ([192.168.24.2]) by bar5.cudamail.com with ESMTP id Ekj7Rr4YPFxnh1s2 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Tue, 08 Sep 2015 17:17:45 -0600 (MDT) X-Barracuda-Envelope-From: azhou@nicira.com X-Barracuda-RBL-Trusted-Forwarder: 192.168.24.2 Received: from unknown (HELO mail-pa0-f45.google.com) (209.85.220.45) by mx1-pf2.cudamail.com with ESMTPS (RC4-SHA encrypted); 8 Sep 2015 23:17:45 -0000 Received-SPF: unknown (mx1-pf2.cudamail.com: Multiple SPF records returned) X-Barracuda-RBL-Trusted-Forwarder: 209.85.220.45 Received: by padhy16 with SMTP id hy16so134743871pad.1 for ; Tue, 08 Sep 2015 16:17:44 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=n/f/ZkXZDhRtXSokZeZidq9nankIn8o+DB6+G8XlvR0=; b=kVesI1i6HiTLLli8wVCzxkAG7zeVylohlh+5TNvfnVhvJa2SWrb9adqm9+9R845QUj HV+foKhlrdoHh1b/Z7dO1PUZAJlWwmdswn9EhMSzxLsYLhNhPPOXQkuuFHe2BMlCIiEc RDnBGddnYLjeJKweUdUPFN0jryoBSsx7+LKnuLPsl2lNc0NcxoS2cxF7LugIJviW78oM vpopbiAtC3SfyZgi8zeq9zfQNkqaEH89Aa1tMZI+9ekvBEfJKvIjMaj/ALfeNKl/RUmm dLtpltOcrhO03kyuchZh96ilgeqvKQO6ESsxqOEVLpeFEKU2Il54/SoUfSB84TCVmS5x XMRg== X-Gm-Message-State: ALoCoQlsMZhAquBzkSxblbr52Cwppx+hQ0r1rCJExhoF7kqeqKkC43vIqL2NCnNKmUiWvHSW4Koy X-Received: by 10.66.164.230 with SMTP id yt6mr53230649pab.149.1441754264560; Tue, 08 Sep 2015 16:17:44 -0700 (PDT) Received: from localhost.localdomain ([208.91.2.3]) by smtp.gmail.com with ESMTPSA id bh16sm4676907pdb.67.2015.09.08.16.17.43 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 08 Sep 2015 16:17:43 -0700 (PDT) X-CudaMail-Envelope-Sender: azhou@nicira.com X-Barracuda-Apparent-Source-IP: 208.91.2.3 From: Andy Zhou To: dev@openvswitch.org X-CudaMail-Whitelist-To: dev@openvswitch.org X-CudaMail-MID: CM-E2-907102629 X-CudaMail-DTE: 090815 X-CudaMail-Originating-IP: 209.85.220.45 Date: Tue, 8 Sep 2015 16:17:37 -0700 X-ASG-Orig-Subj: [##CM-E2-907102629##][v2 2/3] lib: Add --user for daemon Message-Id: <1441754258-9868-2-git-send-email-azhou@nicira.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1441754258-9868-1-git-send-email-azhou@nicira.com> References: <1441754258-9868-1-git-send-email-azhou@nicira.com> X-Barracuda-Connect: UNKNOWN[192.168.24.2] X-Barracuda-Start-Time: 1441754265 X-Barracuda-Encrypted: DHE-RSA-AES256-SHA X-Barracuda-URL: https://web.cudamail.com:443/cgi-mod/mark.cgi X-ASG-Whitelist: Header =?UTF-8?B?eFwtY3VkYW1haWxcLXdoaXRlbGlzdFwtdG8=?= X-Virus-Scanned: by bsmtpd at cudamail.com X-Barracuda-BRTS-Status: 1 Subject: [ovs-dev] [v2 2/3] lib: Add --user for daemon X-BeenThere: dev@openvswitch.org X-Mailman-Version: 2.1.16 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dev-bounces@openvswitch.org Sender: "dev" Allow daemon running as root to accept --user option, that accepts "user:group" string as input. Performs sanity check on the input, and store the converted uid and gid. daemon_become_new_user() needs to be called to make the actual switch. Signed-off-by: Andy Zhou --- v2 : use sysconf() to get proper buffer size. not hard code it --- lib/daemon-unix.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ lib/daemon.h | 27 ++++++++++++++----- 2 files changed, 97 insertions(+), 7 deletions(-) diff --git a/lib/daemon-unix.c b/lib/daemon-unix.c index 4a2e7b4..ee1761a 100644 --- a/lib/daemon-unix.c +++ b/lib/daemon-unix.c @@ -20,6 +20,7 @@ #include #include #include +#include #include #include #include @@ -693,6 +694,82 @@ should_service_stop(void) return false; } +void daemon_set_new_user(const char *user_spec) +{ + char *pos = strchr(user_spec, ':'); + int bufsize; + + uid = getuid(); + gid = getgid(); + + if (gid || uid) { + VLOG_FATAL("%s: only root can use --user option", pidfile); + } + + if ((bufsize = sysconf(_SC_GETPW_R_SIZE_MAX)) == -1) { + VLOG_FATAL("%s: Invalid --user option %s (Unknown system password " + "configuration)", pidfile, user_spec); + } + + user_spec += strspn(user_spec, " \t\r\n"); + int len = pos ? pos - user_spec : strlen(user_spec); + struct passwd pwd, *res; + char buf[bufsize]; + + if (len) { + user = xzalloc(len + 1); + strncpy(user, user_spec, len); + + if (getpwnam_r(user, &pwd, buf, bufsize, &res)) { + VLOG_FATAL("%s: Invalid --user option %s (no such user %s)", + pidfile, user_spec, user); + } + } else { + /* User is not specified, use current user. */ + if (getpwuid_r(uid, &pwd, buf, bufsize, &res)) { + VLOG_FATAL("%s: Invalid --user option %s (failed to lookup " + "current user with uid %d)", pidfile, user_spec, uid); + } + user = strdup(pwd.pw_name); + } + + uid = pwd.pw_uid; + gid = pwd.pw_gid; + + if (pos) { + char *grpstr = pos + 1; + grpstr += strspn(grpstr, " \t\r\n"); + + if (*grpstr) { + struct group grp, *res; + + if(getgrnam_r(grpstr, &grp, buf, bufsize, &res)) { + VLOG_FATAL("%s: Invalid --user option %s (unknown group %s)", + pidfile, user_spec, grpstr); + } + + if(gid != grp.gr_gid) { + char **mem; + + for(mem = grp.gr_mem; *mem; ++mem) { + if (!strcmp(*mem, user)) { + break; + } + } + + if (!*mem) { + VLOG_FATAL("%s: Invalid --user option %s (user %s is " + "not in group %s)", pidfile, user_spec, + user, grpstr); + } + gid = grp.gr_gid; + } + } + } + + switch_to_new_user = true; +} + void daemon_become_new_user(void) { diff --git a/lib/daemon.h b/lib/daemon.h index ccf30f8..b00c698 100644 --- a/lib/daemon.h +++ b/lib/daemon.h @@ -42,14 +42,16 @@ OPT_NO_CHDIR, \ OPT_OVERWRITE_PIDFILE, \ OPT_PIDFILE, \ - OPT_MONITOR + OPT_MONITOR, \ + OPT_USER_GROUP -#define DAEMON_LONG_OPTIONS \ - {"detach", no_argument, NULL, OPT_DETACH}, \ - {"no-chdir", no_argument, NULL, OPT_NO_CHDIR}, \ - {"pidfile", optional_argument, NULL, OPT_PIDFILE}, \ +#define DAEMON_LONG_OPTIONS \ + {"detach", no_argument, NULL, OPT_DETACH}, \ + {"no-chdir", no_argument, NULL, OPT_NO_CHDIR}, \ + {"pidfile", optional_argument, NULL, OPT_PIDFILE}, \ {"overwrite-pidfile", no_argument, NULL, OPT_OVERWRITE_PIDFILE}, \ - {"monitor", no_argument, NULL, OPT_MONITOR} + {"monitor", no_argument, NULL, OPT_MONITOR}, \ + {"user", required_argument, NULL, OPT_USER_GROUP} #define DAEMON_OPTION_HANDLERS \ case OPT_DETACH: \ @@ -70,6 +72,10 @@ \ case OPT_MONITOR: \ daemon_set_monitor(); \ + break; \ + \ + case OPT_USER_GROUP: \ + daemon_set_new_user(optarg); \ break; void set_detach(void); @@ -77,6 +83,7 @@ void daemon_set_monitor(void); void set_no_chdir(void); void ignore_existing_pidfile(void); void daemon_become_new_user(void); +void daemon_set_new_user(const char *); pid_t read_pidfile(const char *name); #else #define DAEMON_OPTION_ENUMS \ @@ -85,7 +92,7 @@ pid_t read_pidfile(const char *name); OPT_PIDFILE, \ OPT_PIPE_HANDLE, \ OPT_SERVICE, \ - OPT_SERVICE_MONITOR + OPT_SERVICE_MONITOR \ #define DAEMON_LONG_OPTIONS \ {"detach", no_argument, NULL, OPT_DETACH}, \ @@ -120,6 +127,12 @@ void control_handler(DWORD request); void set_pipe_handle(const char *pipe_handle); static inline void +daemon_set_new_user(const char *) +{ + /* Not implemented. */ +} + +static inline void daemon_become_new_user(void) { /* Not implemented. */