*: use frr_elevate_privs() (2/2: manual)

Signed-off-by: David Lamparter <equinox@diac24.net>

5 files changed, 55 insertions, 90 deletions

diff --git a/zebra/if_ioctl_solaris.c b/zebra/if_ioctl_solaris.c
index ee7f22e780..5a58fe1751 100644
--- a/zebra/if_ioctl_solaris.c
+++ b/zebra/if_ioctl_solaris.c
@@ -60,19 +60,21 @@ static int interface_list_ioctl(int af)
 	char *buf = NULL;
 
 	frr_elevate_privs(&zserv_privs) {
-
 		sock = socket(af, SOCK_DGRAM, 0);
-		if (sock < 0) {
-			zlog_warn("Can't make %s socket stream: %s",
-				  (af == AF_INET ? "AF_INET" : "AF_INET6"),
-				  safe_strerror(errno));
+	}
 
-			return -1;
-		}
+	if (sock < 0) {
+		zlog_warn("Can't make %s socket stream: %s",
+			  (af == AF_INET ? "AF_INET" : "AF_INET6"),
+			  safe_strerror(errno));
+		return -1;
+	}
 
-calculate_lifc_len: /* must hold privileges to enter here */
+calculate_lifc_len:
+	frr_elevate_privs(&zserv_privs) {
 		lifn.lifn_family = af;
-		lifn.lifn_flags = LIFC_NOXMIT; /* we want NOXMIT interfaces too */
+		lifn.lifn_flags = LIFC_NOXMIT;
+		/* we want NOXMIT interfaces too */
 		ret = ioctl(sock, SIOCGLIFNUM, &lifn);
 		save_errno = errno;
 
@@ -105,27 +107,18 @@ calculate_lifc_len: /* must hold privileges to enter here */
 	lifconf.lifc_len = needed;
 	lifconf.lifc_buf = buf;
 
-	if (zserv_privs.change(ZPRIVS_RAISE))
-		flog_err(LIB_ERR_PRIVILEGES, "Can't raise privileges");
-
-	ret = ioctl(sock, SIOCGLIFCONF, &lifconf);
+	frr_elevate_privs(&zserv_privs) {
+		ret = ioctl(sock, SIOCGLIFCONF, &lifconf);
+	}
 
 	if (ret < 0) {
 		if (errno == EINVAL)
-			goto calculate_lifc_len; /* deliberately hold privileges
-						    */
+			goto calculate_lifc_len;
 
 		zlog_warn("SIOCGLIFCONF: %s", safe_strerror(errno));
-
-		if (zserv_privs.change(ZPRIVS_LOWER))
-			flog_err(LIB_ERR_PRIVILEGES, "Can't lower privileges");
-
 		goto end;
 	}
 
-	if (zserv_privs.change(ZPRIVS_LOWER))
-		flog_err(LIB_ERR_PRIVILEGES, "Can't lower privileges");
-
 	/* Allocate interface. */
 	lifreq = lifconf.lifc_req;
 
diff --git a/zebra/kernel_netlink.c b/zebra/kernel_netlink.c
index b397e95955..176ee93cdc 100644
--- a/zebra/kernel_netlink.c
+++ b/zebra/kernel_netlink.c
@@ -206,34 +206,26 @@ static int netlink_socket(struct nlsock *nl, unsigned long groups,
 	struct sockaddr_nl snl;
 	int sock;
 	int namelen;
-	int save_errno;
-
-	if (zserv_privs.change(ZPRIVS_RAISE)) {
-		flog_err(LIB_ERR_PRIVILEGES, "Can't raise privileges");
-		return -1;
-	}
 
-	sock = ns_socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE, ns_id);
-	if (sock < 0) {
-		flog_err_sys(LIB_ERR_SOCKET, "Can't open %s socket: %s",
-			     nl->name, safe_strerror(errno));
-		return -1;
-	}
+	frr_elevate_privs(&zserv_privs) {
+		sock = ns_socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE, ns_id);
+		if (sock < 0) {
+			zlog_err("Can't open %s socket: %s", nl->name,
+				 safe_strerror(errno));
+			return -1;
+		}
 
-	memset(&snl, 0, sizeof snl);
-	snl.nl_family = AF_NETLINK;
-	snl.nl_groups = groups;
+		memset(&snl, 0, sizeof snl);
+		snl.nl_family = AF_NETLINK;
+		snl.nl_groups = groups;
 
-	/* Bind the socket to the netlink structure for anything. */
-	ret = bind(sock, (struct sockaddr *)&snl, sizeof snl);
-	save_errno = errno;
-	if (zserv_privs.change(ZPRIVS_LOWER))
-		flog_err(LIB_ERR_PRIVILEGES, "Can't lower privileges");
+		/* Bind the socket to the netlink structure for anything. */
+		ret = bind(sock, (struct sockaddr *)&snl, sizeof snl);
+	}
 
 	if (ret < 0) {
-		flog_err_sys(LIB_ERR_SOCKET,
-			     "Can't bind %s socket to group 0x%x: %s", nl->name,
-			     snl.nl_groups, safe_strerror(save_errno));
+		zlog_err("Can't bind %s socket to group 0x%x: %s", nl->name,
+			 snl.nl_groups, safe_strerror(errno));
 		close(sock);
 		return -1;
 	}
@@ -340,15 +332,15 @@ static void netlink_write_incoming(const char *buf, const unsigned int size,
 	char fname[MAXPATHLEN];
 	FILE *f;
 
-	zserv_privs.change(ZPRIVS_RAISE);
 	snprintf(fname, MAXPATHLEN, "%s/%s_%u", DAEMON_VTY_DIR, "netlink",
 		 counter);
-	f = fopen(fname, "w");
+	frr_elevate_privs(&zserv_privs) {
+		f = fopen(fname, "w");
+	}
 	if (f) {
 		fwrite(buf, 1, size, f);
 		fclose(f);
 	}
-	zserv_privs.change(ZPRIVS_LOWER);
 }
 
 /**
@@ -363,8 +355,9 @@ static long netlink_read_file(char *buf, const char *fname)
 	FILE *f;
 	long file_bytes = -1;
 
-	zserv_privs.change(ZPRIVS_RAISE);
-	f = fopen(fname, "r");
+	frr_elevate_privs(&zserv_privs) {
+		f = fopen(fname, "r");
+	}
 	if (f) {
 		fseek(f, 0, SEEK_END);
 		file_bytes = ftell(f);
@@ -372,7 +365,6 @@ static long netlink_read_file(char *buf, const char *fname)
 		fread(buf, NL_RCV_PKT_BUF_SIZE, 1, f);
 		fclose(f);
 	}
-	zserv_privs.change(ZPRIVS_LOWER);
 	return file_bytes;
 }
 
@@ -985,7 +977,6 @@ int netlink_request(struct nlsock *nl, struct nlmsghdr *n)
 {
 	int ret;
 	struct sockaddr_nl snl;
-	int save_errno;
 
 	/* Check netlink socket. */
 	if (nl->sock < 0) {
@@ -1003,21 +994,14 @@ int netlink_request(struct nlsock *nl, struct nlmsghdr *n)
 	snl.nl_family = AF_NETLINK;
 
 	/* Raise capabilities and send message, then lower capabilities. */
-	if (zserv_privs.change(ZPRIVS_RAISE)) {
-		flog_err(LIB_ERR_PRIVILEGES, "Can't raise privileges");
-		return -1;
+	frr_elevate_privs(&zserv_privs) {
+		ret = sendto(nl->sock, (void *)n, n->nlmsg_len, 0,
+			     (struct sockaddr *)&snl, sizeof snl);
 	}
 
-	ret = sendto(nl->sock, (void *)n, n->nlmsg_len, 0,
-		     (struct sockaddr *)&snl, sizeof snl);
-	save_errno = errno;
-
-	if (zserv_privs.change(ZPRIVS_LOWER))
-		flog_err(LIB_ERR_PRIVILEGES, "Can't lower privileges");
-
 	if (ret < 0) {
-		flog_err_sys(LIB_ERR_SOCKET, "%s sendto failed: %s", nl->name,
-			     safe_strerror(save_errno));
+		zlog_err("%s sendto failed: %s", nl->name,
+			 safe_strerror(errno));
 		return -1;
 	}
 
diff --git a/zebra/kernel_socket.c b/zebra/kernel_socket.c
index 79721cf87a..78e25e7626 100644
--- a/zebra/kernel_socket.c
+++ b/zebra/kernel_socket.c
@@ -1385,17 +1385,11 @@ static int kernel_read(struct thread *thread)
 /* Make routing socket. */
 static void routing_socket(struct zebra_ns *zns)
 {
-	if (zserv_privs.change(ZPRIVS_RAISE))
-		flog_err(LIB_ERR_PRIVILEGES,
-			  "routing_socket: Can't raise privileges");
-
-	routing_sock =
-		ns_socket(AF_ROUTE, SOCK_RAW, 0, zns->ns_id);
+	frr_elevate_privs(&zserv_privs) {
+		routing_sock = ns_socket(AF_ROUTE, SOCK_RAW, 0, zns->ns_id);
+	}
 
 	if (routing_sock < 0) {
-		if (zserv_privs.change(ZPRIVS_LOWER))
-			flog_err(LIB_ERR_PRIVILEGES,
-				  "routing_socket: Can't lower privileges");
 		zlog_warn("Can't init kernel routing socket");
 		return;
 	}
@@ -1407,10 +1401,6 @@ static void routing_socket(struct zebra_ns *zns)
 	/*if (fcntl (routing_sock, F_SETFL, O_NONBLOCK) < 0)
 	  zlog_warn ("Can't set O_NONBLOCK to routing socket");*/
 
-	if (zserv_privs.change(ZPRIVS_LOWER))
-		flog_err(LIB_ERR_PRIVILEGES,
-			  "routing_socket: Can't lower privileges");
-
 	/* kernel_read needs rewrite. */
 	thread_add_read(zebrad.master, kernel_read, NULL, routing_sock, NULL);
 }
diff --git a/zebra/zapi_msg.c b/zebra/zapi_msg.c
index a74c6bc4bf..008fc8f066 100644
--- a/zebra/zapi_msg.c
+++ b/zebra/zapi_msg.c
@@ -3087,12 +3087,13 @@ static void zserv_write_incoming(struct stream *orig, uint16_t command)
 	copy = stream_dup(orig);
 	stream_set_getp(copy, 0);
 
-	zserv_privs.change(ZPRIVS_RAISE);
 	snprintf(fname, MAXPATHLEN, "%s/%u", DAEMON_VTY_DIR, command);
-	fd = open(fname, O_CREAT | O_WRONLY | O_EXCL, 0644);
+
+	frr_elevate_privs(&zserv_privs) {
+		fd = open(fname, O_CREAT | O_WRONLY | O_EXCL, 0644);
+	}
 	stream_flush(copy, fd);
 	close(fd);
-	zserv_privs.change(ZPRIVS_LOWER);
 	stream_free(copy);
 }
 #endif
diff --git a/zebra/zserv.c b/zebra/zserv.c
index 553331867c..174e010743 100644
--- a/zebra/zserv.c
+++ b/zebra/zserv.c
@@ -787,15 +787,14 @@ void zserv_start(char *path)
 			unlink(suna->sun_path);
 	}
 
-	zserv_privs.change(ZPRIVS_RAISE);
-	setsockopt_so_recvbuf(zebrad.sock, 1048576);
-	setsockopt_so_sendbuf(zebrad.sock, 1048576);
-	zserv_privs.change(ZPRIVS_LOWER);
-
-	if (sa.ss_family != AF_UNIX && zserv_privs.change(ZPRIVS_RAISE))
-		flog_err(LIB_ERR_PRIVILEGES, "Can't raise privileges");
+	frr_elevate_privs(&zserv_privs) {
+		setsockopt_so_recvbuf(zebrad.sock, 1048576);
+		setsockopt_so_sendbuf(zebrad.sock, 1048576);
+	}
 
-	ret = bind(zebrad.sock, (struct sockaddr *)&sa, sa_len);
+	frr_elevate_privs((sa.ss_family != AF_UNIX) ? &zserv_privs : NULL) {
+		ret = bind(zebrad.sock, (struct sockaddr *)&sa, sa_len);
+	}
 	if (ret < 0) {
 		zlog_warn("Can't bind zserv socket on %s: %s", path,
 			  safe_strerror(errno));
@@ -805,8 +804,6 @@ void zserv_start(char *path)
 		zebrad.sock = -1;
 		return;
 	}
-	if (sa.ss_family != AF_UNIX && zserv_privs.change(ZPRIVS_LOWER))
-		flog_err(LIB_ERR_PRIVILEGES, "Can't lower privileges");
 
 	ret = listen(zebrad.sock, 5);
 	if (ret < 0) {