sock.c

   1 #include <sys/types.h>
   2 #include <sys/socket.h>
   3 #include <fcntl.h>
   4 #include <arpa/inet.h>
   5 #include <linux/if_ether.h>
   6 #include <linux/tcp.h>
   7
   8 #include "sock.h"
   9 #include "die.h"
  10 #include "str.h"
  11 #include "linktype.h"
  12 #include "built_in.h"
  13 #include "sysctl.h"
  14
  15 int af_socket(int af)
  16 {
  17         int sock;
  18
  19         if (unlikely(af != AF_INET && af != AF_INET6))
  20                 panic("Wrong AF socket type!\n");
  21
  22         sock = socket(af, SOCK_DGRAM, 0);
  23         if (unlikely(sock < 0))
  24                 panic("Creation AF socket failed: %s\n", strerror(errno));
  25
  26         return sock;
  27 }
  28
  29 int pf_socket(void)
  30 {
  31         int sock = socket(PF_PACKET, SOCK_RAW, 0);
  32         if (unlikely(sock < 0))
  33                 panic("Creation of PF socket failed: %s\n", strerror(errno));
  34
  35         return sock;
  36 }
  37
  38 static int pf_socket_dgram(void)
  39 {
  40         int sock = socket(PF_PACKET, SOCK_DGRAM, 0);
  41         if (unlikely(sock < 0))
  42                 panic("Creation of PF dgram socket failed: %s\n",
  43                       strerror(errno));
  44
  45         return sock;
  46 }
  47
  48 int pf_socket_type(uint32_t type)
  49 {
  50         switch (type) {
  51         case LINKTYPE_LINUX_SLL:
  52                 return pf_socket_dgram();
  53         default:
  54                 return pf_socket();
  55         }
  56 }
  57
  58 /* Available in kernel >= 3.14
  59  * in commit d346a3fae3 (packet: introduce PACKET_QDISC_BYPASS socket option)
  60  */
  61 void set_sock_qdisc_bypass(int fd, bool verbose)
  62 {
  63         int ret, val = 1;
  64
  65         ret = setsockopt(fd, SOL_PACKET, PACKET_QDISC_BYPASS, &val, sizeof(val));
  66         if (ret < 0) {
  67                 if (errno == ENOPROTOOPT) {
  68                         if (verbose)
  69                                 printf("No kernel support for PACKET_QDISC_BYPASS"
  70                                        " (kernel < 3.14?)\n");
  71                 } else
  72                         perror("Cannot set PACKET_QDISC_BYPASS");
  73         } else
  74                 if (verbose) printf("Enabled kernel qdisc bypass\n");
  75 }
  76
  77 void set_sock_prio(int fd, int prio)
  78 {
  79         int ret, val = prio;
  80
  81         ret = setsockopt(fd, SOL_SOCKET, SO_PRIORITY, &val, sizeof(val));
  82         if (unlikely(ret))
  83                 panic("Cannot set socket priority: %s\n", strerror(errno));
  84 }
  85
  86 void set_nonblocking(int fd)
  87 {
  88         int ret = fcntl(fd, F_SETFL, fcntl(fd, F_GETFD, 0) | O_NONBLOCK);
  89         if (unlikely(ret < 0))
  90                 panic("Cannot fcntl: %s\n", strerror(errno));
  91 }
  92
  93 int set_nonblocking_sloppy(int fd)
  94 {
  95         return fcntl(fd, F_SETFL, fcntl(fd, F_GETFD, 0) | O_NONBLOCK);
  96 }
  97
  98 void set_socket_keepalive(int fd)
  99 {
 100         int ret, one = 1;
 101
 102         ret = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof(one));
 103         if (unlikely(ret))
 104                 panic("Cannot set TCP keepalive: %s\n", strerror(errno));
 105 }
 106
 107 void set_tcp_nodelay(int fd)
 108 {
 109         int ret, one = 1;
 110
 111         ret = setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one, sizeof(one));
 112         if (unlikely(ret))
 113                 panic("Cannot set TCP nodelay: %s\n", strerror(errno));
 114 }
 115
 116 int set_ipv6_only(int fd)
 117 {
 118         int one = 1;
 119         return setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &one, sizeof(one));
 120 }
 121
 122 int set_reuseaddr(int fd)
 123 {
 124         int ret, one = 1;
 125
 126         ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
 127         if (unlikely(ret < 0))
 128                 panic("Cannot reuse addr: %s\n", strerror(errno));
 129
 130         return 0;
 131 }
 132
 133 void set_mtu_disc_dont(int fd)
 134 {
 135         int mtu = IP_PMTUDISC_DONT, ret;
 136
 137         ret = setsockopt(fd, SOL_IP, IP_MTU_DISCOVER, &mtu, sizeof(mtu));
 138         if (unlikely(ret))
 139                 panic("Cannot set MTU discovery options: %s\n", strerror(errno));
 140 }
 141
 142 enum {
 143         sock_rmem_max = 0,
 144         sock_rmem_def,
 145         sock_wmem_max,
 146         sock_wmem_def,
 147 };
 148
 149 #define SMEM_SUG_MAX    104857600
 150 #define SMEM_SUG_DEF    4194304
 151
 152 static const char *const sock_mem[] = {
 153         [sock_rmem_max] = "net/core/rmem_max",
 154         [sock_rmem_def] = "net/core/rmem_default",
 155         [sock_wmem_max] = "net/core/wmem_max",
 156         [sock_wmem_def] = "net/core/wmem_default",
 157 };
 158
 159 static int get_system_socket_mem(int which)
 160 {
 161         int val;
 162
 163         if (sysctl_get_int(sock_mem[which], &val))
 164                 return -1;
 165
 166         return val;
 167 }
 168
 169 static void set_system_socket_mem(int which, int val)
 170 {
 171         if (val > 0 && sysctl_set_int(sock_mem[which], val))
 172                 printf("Cannot set system socket memory in %s%s: %s\n",
 173                        SYSCTL_PROC_PATH, sock_mem[which], strerror(errno));
 174 }
 175
 176 void set_system_socket_memory(int *vals, size_t len)
 177 {
 178         bug_on(len != 4);
 179
 180         if ((vals[0] = get_system_socket_mem(sock_rmem_max)) < SMEM_SUG_MAX)
 181                 set_system_socket_mem(sock_rmem_max, SMEM_SUG_MAX);
 182         if ((vals[1] = get_system_socket_mem(sock_rmem_def)) < SMEM_SUG_DEF)
 183                 set_system_socket_mem(sock_rmem_def, SMEM_SUG_DEF);
 184         if ((vals[2] = get_system_socket_mem(sock_wmem_max)) < SMEM_SUG_MAX)
 185                 set_system_socket_mem(sock_wmem_max, SMEM_SUG_MAX);
 186         if ((vals[3] = get_system_socket_mem(sock_wmem_def)) < SMEM_SUG_DEF)
 187                 set_system_socket_mem(sock_wmem_def, SMEM_SUG_DEF);
 188 }
 189
 190 void reset_system_socket_memory(int *vals, size_t len)
 191 {
 192         bug_on(len != 4);
 193
 194         set_system_socket_mem(sock_rmem_max, vals[0]);
 195         set_system_socket_mem(sock_rmem_def, vals[1]);
 196         set_system_socket_mem(sock_wmem_max, vals[2]);
 197         set_system_socket_mem(sock_wmem_def, vals[3]);
 198 }