arch/um/drivers/net_user.c

   1 /*
   2  * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <stddef.h>
   7 #include <stdarg.h>
   8 #include <unistd.h>
   9 #include <stdio.h>
  10 #include <errno.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <sys/socket.h>
  14 #include <sys/wait.h>
  15 #include "user.h"
  16 #include "user_util.h"
  17 #include "kern_util.h"
  18 #include "net_user.h"
  19 #include "helper.h"
  20 #include "os.h"
  21
  22 int tap_open_common(void *dev, char *gate_addr)
  23 {
  24         int tap_addr[4];
  25
  26         if(gate_addr == NULL) return(0);
  27         if(sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0],
  28                   &tap_addr[1], &tap_addr[2], &tap_addr[3]) != 4){
  29                 printk("Invalid tap IP address - '%s'\n", gate_addr);
  30                 return(-EINVAL);
  31         }
  32         return(0);
  33 }
  34
  35 void tap_check_ips(char *gate_addr, char *eth_addr)
  36 {
  37         int tap_addr[4];
  38
  39         if((gate_addr != NULL) &&
  40            (sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0],
  41                    &tap_addr[1], &tap_addr[2], &tap_addr[3]) == 4) &&
  42            (eth_addr[0] == tap_addr[0]) &&
  43            (eth_addr[1] == tap_addr[1]) &&
  44            (eth_addr[2] == tap_addr[2]) &&
  45            (eth_addr[3] == tap_addr[3])){
  46                 printk("The tap IP address and the UML eth IP address"
  47                        " must be different\n");
  48         }
  49 }
  50
  51 void read_output(int fd, char *output, int len)
  52 {
  53         int remain, n, actual;
  54         char c;
  55
  56         if(output == NULL){
  57                 output = &c;
  58                 len = sizeof(c);
  59         }
  60
  61         *output = '\0';
  62         n = os_read_file(fd, &remain, sizeof(remain));
  63         if(n != sizeof(remain)){
  64                 printk("read_output - read of length failed, err = %d\n", -n);
  65                 return;
  66         }
  67
  68         while(remain != 0){
  69                 n = (remain < len) ? remain : len;
  70                 actual = os_read_file(fd, output, n);
  71                 if(actual != n){
  72                         printk("read_output - read of data failed, "
  73                                "err = %d\n", -actual);
  74                         return;
  75                 }
  76                 remain -= actual;
  77         }
  78         return;
  79 }
  80
  81 int net_read(int fd, void *buf, int len)
  82 {
  83         int n;
  84
  85         n = os_read_file(fd,  buf,  len);
  86
  87         if(n == -EAGAIN)
  88                 return(0);
  89         else if(n == 0)
  90                 return(-ENOTCONN);
  91         return(n);
  92 }
  93
  94 int net_recvfrom(int fd, void *buf, int len)
  95 {
  96         int n;
  97
  98         while(((n = recvfrom(fd,  buf,  len, 0, NULL, NULL)) < 0) &&
  99               (errno == EINTR)) ;
 100
 101         if(n < 0){
 102                 if(errno == EAGAIN) return(0);
 103                 return(-errno);
 104         }
 105         else if(n == 0) return(-ENOTCONN);
 106         return(n);
 107 }
 108
 109 int net_write(int fd, void *buf, int len)
 110 {
 111         int n;
 112
 113         n = os_write_file(fd, buf, len);
 114
 115         if(n == -EAGAIN)
 116                 return(0);
 117         else if(n == 0)
 118                 return(-ENOTCONN);
 119         return(n);
 120 }
 121
 122 int net_send(int fd, void *buf, int len)
 123 {
 124         int n;
 125
 126         while(((n = send(fd, buf, len, 0)) < 0) && (errno == EINTR)) ;
 127         if(n < 0){
 128                 if(errno == EAGAIN) return(0);
 129                 return(-errno);
 130         }
 131         else if(n == 0) return(-ENOTCONN);
 132         return(n);
 133 }
 134
 135 int net_sendto(int fd, void *buf, int len, void *to, int sock_len)
 136 {
 137         int n;
 138
 139         while(((n = sendto(fd, buf, len, 0, (struct sockaddr *) to,
 140                            sock_len)) < 0) && (errno == EINTR)) ;
 141         if(n < 0){
 142                 if(errno == EAGAIN) return(0);
 143                 return(-errno);
 144         }
 145         else if(n == 0) return(-ENOTCONN);
 146         return(n);
 147 }
 148
 149 struct change_pre_exec_data {
 150         int close_me;
 151         int stdout;
 152 };
 153
 154 static void change_pre_exec(void *arg)
 155 {
 156         struct change_pre_exec_data *data = arg;
 157
 158         os_close_file(data->close_me);
 159         dup2(data->stdout, 1);
 160 }
 161
 162 static int change_tramp(char **argv, char *output, int output_len)
 163 {
 164         int pid, fds[2], err;
 165         struct change_pre_exec_data pe_data;
 166
 167         err = os_pipe(fds, 1, 0);
 168         if(err < 0){
 169                 printk("change_tramp - pipe failed, err = %d\n", -err);
 170                 return(err);
 171         }
 172         pe_data.close_me = fds[0];
 173         pe_data.stdout = fds[1];
 174         pid = run_helper(change_pre_exec, &pe_data, argv, NULL);
 175
 176         read_output(fds[0], output, output_len);
 177         os_close_file(fds[0]);
 178         os_close_file(fds[1]);
 179
 180         if (pid > 0)
 181                 CATCH_EINTR(err = waitpid(pid, NULL, 0));
 182         return(pid);
 183 }
 184
 185 static void change(char *dev, char *what, unsigned char *addr,
 186                    unsigned char *netmask)
 187 {
 188         char addr_buf[sizeof("255.255.255.255\0")];
 189         char netmask_buf[sizeof("255.255.255.255\0")];
 190         char version[sizeof("nnnnn\0")];
 191         char *argv[] = { "uml_net", version, what, dev, addr_buf,
 192                          netmask_buf, NULL };
 193         char *output;
 194         int output_len, pid;
 195
 196         sprintf(version, "%d", UML_NET_VERSION);
 197         sprintf(addr_buf, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]);
 198         sprintf(netmask_buf, "%d.%d.%d.%d", netmask[0], netmask[1],
 199                 netmask[2], netmask[3]);
 200
 201         output_len = page_size();
 202         output = um_kmalloc(output_len);
 203         if(output == NULL)
 204                 printk("change : failed to allocate output buffer\n");
 205
 206         pid = change_tramp(argv, output, output_len);
 207         if(pid < 0) return;
 208
 209         if(output != NULL){
 210                 printk("%s", output);
 211                 kfree(output);
 212         }
 213 }
 214
 215 void open_addr(unsigned char *addr, unsigned char *netmask, void *arg)
 216 {
 217         change(arg, "add", addr, netmask);
 218 }
 219
 220 void close_addr(unsigned char *addr, unsigned char *netmask, void *arg)
 221 {
 222         change(arg, "del", addr, netmask);
 223 }
 224
 225 char *split_if_spec(char *str, ...)
 226 {
 227         char **arg, *end;
 228         va_list ap;
 229
 230         va_start(ap, str);
 231         while((arg = va_arg(ap, char **)) != NULL){
 232                 if(*str == '\0')
 233                         return(NULL);
 234                 end = strchr(str, ',');
 235                 if(end != str)
 236                         *arg = str;
 237                 if(end == NULL)
 238                         return(NULL);
 239                 *end++ = '\0';
 240                 str = end;
 241         }
 242         va_end(ap);
 243         return(str);
 244 }
 245
 246 /*
 247  * Overrides for Emacs so that we follow Linus's tabbing style.
 248  * Emacs will notice this stuff at the end of the file and automatically
 249  * adjust the settings for this buffer only.  This must remain at the end
 250  * of the file.
 251  * ---------------------------------------------------------------------------
 252  * Local variables:
 253  * c-file-style: "linux"
 254  * End:
 255  */