treewide: improve error handling
authorHans Dedecker <dedeckeh@gmail.com>
Tue, 27 Mar 2018 19:00:08 +0000 (21:00 +0200)
committerHans Dedecker <dedeckeh@gmail.com>
Sat, 31 Mar 2018 16:05:14 +0000 (18:05 +0200)
Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
src/dhcpv6.c
src/ra.c

index f98819ef5cf20c290fcbeec524dc03880366470e..1e051b9ddf3cf4c5964b96b67010b277f4fa56d3 100644 (file)
@@ -130,14 +130,14 @@ int init_dhcpv6(const char *ifname, unsigned int options, int sol_timeout)
 
        sock = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, IPPROTO_UDP);
        if (sock < 0)
-               return -1;
+               goto failure;
 
        // Detect interface
        struct ifreq ifr;
        memset(&ifr, 0, sizeof(ifr));
        strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
        if (ioctl(sock, SIOCGIFINDEX, &ifr) < 0)
-               return -1;
+               goto failure;
 
        ifindex = ifr.ifr_ifindex;
 
@@ -202,18 +202,31 @@ int init_dhcpv6(const char *ifname, unsigned int options, int sol_timeout)
 
        // Configure IPv6-options
        int val = 1;
-       setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val));
-       setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val));
-       setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val, sizeof(val));
-       setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
+       if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &val, sizeof(val)) < 0)
+               goto failure;
+
+       if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) < 0)
+               goto failure;
+
+       if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val, sizeof(val)) < 0)
+               goto failure;
+
+       if (setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname)) < 0)
+               goto failure;
 
        struct sockaddr_in6 client_addr = { .sin6_family = AF_INET6,
                .sin6_port = htons(DHCPV6_CLIENT_PORT), .sin6_flowinfo = 0 };
 
        if (bind(sock, (struct sockaddr*)&client_addr, sizeof(client_addr)) < 0)
-               return -1;
+               goto failure;
 
        return 0;
+
+failure:
+       if (sock >= 0)
+               close(sock);
+
+       return -1;
 }
 
 enum {
@@ -616,8 +629,10 @@ int dhcpv6_request(enum dhcpv6_msg type)
                        // Set timeout for receiving
                        uint64_t t = round_end - round_start;
                        struct timeval tv = {t / 1000, (t % 1000) * 1000};
-                       setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO,
-                                       &tv, sizeof(tv));
+                       if (setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO,
+                                       &tv, sizeof(tv)) < 0)
+                               syslog(LOG_ERR, "setsockopt SO_RCVTIMEO failed (%s)",
+                                               strerror(errno));
 
                        // Receive cycle
                        len = recvmsg(sock, &msg, 0);
index 397608a246e0a26fa466afb1b3856d1ea10e6a13..84925081a31c2b49513cc68fd87aed0d98be6671 100644 (file)
--- a/src/ra.c
+++ b/src/ra.c
@@ -13,6 +13,7 @@
  *
  */
 
+#include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
 #include <signal.h>
@@ -77,27 +78,32 @@ int ra_init(const char *ifname, const struct in6_addr *ifid,
        const pid_t ourpid = getpid();
        sock = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_ICMPV6);
        if (sock < 0)
-               return -1;
+               goto failure;
 
        if_index = if_nametoindex(ifname);
        if (!if_index)
-               return -1;
+               goto failure;
 
        strncpy(if_name, ifname, sizeof(if_name) - 1);
        lladdr = *ifid;
 
        rtnl = socket(AF_NETLINK, SOCK_DGRAM | SOCK_CLOEXEC, NETLINK_ROUTE);
        if (rtnl < 0)
-               return -1;
+               goto failure;
 
        struct sockaddr_nl rtnl_kernel = { .nl_family = AF_NETLINK };
        if (connect(rtnl, (const struct sockaddr*)&rtnl_kernel, sizeof(rtnl_kernel)) < 0)
-               return -1;
+               goto failure;
 
        int val = RTNLGRP_LINK;
-       setsockopt(rtnl, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &val, sizeof(val));
-       fcntl(rtnl, F_SETOWN, ourpid);
-       fcntl(rtnl, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC);
+       if (setsockopt(rtnl, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &val, sizeof(val)) < 0)
+               goto failure;
+
+       if (fcntl(rtnl, F_SETOWN, ourpid) < 0)
+               goto failure;
+
+       if (fcntl(rtnl, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC) < 0)
+               goto failure;
 
        struct {
                struct nlmsghdr hdr;
@@ -106,43 +112,67 @@ int ra_init(const char *ifname, const struct in6_addr *ifid,
                .hdr = {sizeof(req), RTM_GETLINK, NLM_F_REQUEST, 1, 0},
                .ifi = {.ifi_index = if_index}
        };
-       send(rtnl, &req, sizeof(req), 0);
+       if (send(rtnl, &req, sizeof(req), 0) < 0)
+               goto failure;
+
        ra_link_up();
 
        // Filter ICMPv6 package types
        struct icmp6_filter filt;
        ICMP6_FILTER_SETBLOCKALL(&filt);
        ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filt);
-       setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, sizeof(filt));
+       if (setsockopt(sock, IPPROTO_ICMPV6, ICMP6_FILTER, &filt, sizeof(filt)) < 0)
+               goto failure;
 
        // Bind to all-nodes
        struct ipv6_mreq an = {ALL_IPV6_NODES, if_index};
-       setsockopt(sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &an, sizeof(an));
+       if (setsockopt(sock, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &an, sizeof(an)) < 0)
+               goto failure;
 
        // Let the kernel compute our checksums
        val = 2;
-       setsockopt(sock, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val));
+       if (setsockopt(sock, IPPROTO_RAW, IPV6_CHECKSUM, &val, sizeof(val)) < 0)
+               goto failure;
 
        // This is required by RFC 4861
        val = 255;
-       setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val, sizeof(val));
+       if (setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val, sizeof(val)) < 0)
+               goto failure;
 
        // Receive multicast hops
        val = 1;
-       setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &val, sizeof(val));
+       if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &val, sizeof(val)) < 0)
+               goto failure;
 
        // Bind to one device
-       setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname));
+       if (setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ifname, strlen(ifname)) < 0)
+               goto failure;
 
        // Add async-mode
-       fcntl(sock, F_SETOWN, ourpid);
-       fcntl(sock, F_SETFL, fcntl(sock, F_GETFL) | O_ASYNC);
+       if (fcntl(sock, F_SETOWN, ourpid) < 0)
+               goto failure;
+
+       val = fcntl(sock, F_GETFL);
+       if (val < 0)
+               goto failure;
+
+       if (fcntl(sock, F_SETFL, val | O_ASYNC) < 0)
+               goto failure;
 
        // Send RS
        signal(SIGALRM, ra_send_rs);
        ra_send_rs(SIGALRM);
 
        return 0;
+
+failure:
+       if (sock >= 0)
+               close(sock);
+
+       if (rtnl >= 0)
+               close(rtnl);
+
+       return -1;
 }
 
 static void ra_send_rs(int signal __attribute__((unused)))
@@ -156,7 +186,8 @@ static void ra_send_rs(int signal __attribute__((unused)))
        else
                len = sizeof(struct icmp6_hdr);
 
-       sendto(sock, &rs, len, MSG_DONTWAIT, (struct sockaddr*)&dest, sizeof(dest));
+       if (sendto(sock, &rs, len, MSG_DONTWAIT, (struct sockaddr*)&dest, sizeof(dest)) < 0)
+               syslog(LOG_ERR, "Failed to send RS (%s)",  strerror(errno));
 
        if (++rs_attempt <= 3)
                alarm(4);