/* * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) * Licensed under the GPL */ #include #include #include #include #include #include #include #include #include "net_user.h" #include "kern_constants.h" #include "os.h" #include "um_malloc.h" #include "user.h" int tap_open_common(void *dev, char *gate_addr) { int tap_addr[4]; if (gate_addr == NULL) return 0; if (sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0], &tap_addr[1], &tap_addr[2], &tap_addr[3]) != 4) { printk(UM_KERN_ERR "Invalid tap IP address - '%s'\n", gate_addr); return -EINVAL; } return 0; } void tap_check_ips(char *gate_addr, unsigned char *eth_addr) { int tap_addr[4]; if ((gate_addr != NULL) && (sscanf(gate_addr, "%d.%d.%d.%d", &tap_addr[0], &tap_addr[1], &tap_addr[2], &tap_addr[3]) == 4) && (eth_addr[0] == tap_addr[0]) && (eth_addr[1] == tap_addr[1]) && (eth_addr[2] == tap_addr[2]) && (eth_addr[3] == tap_addr[3])) { printk(UM_KERN_ERR "The tap IP address and the UML eth IP " "address must be different\n"); } } /* Do reliable error handling as this fails frequently enough. */ void read_output(int fd, char *output, int len) { int remain, ret, expected; char c; char *str; if (output == NULL) { output = &c; len = sizeof(c); } *output = '\0'; ret = read(fd, &remain, sizeof(remain)); if (ret != sizeof(remain)) { if (ret < 0) ret = -errno; expected = sizeof(remain); str = "length"; goto err; } while (remain != 0) { expected = (remain < len) ? remain : len; ret = read(fd, output, expected); if (ret != expected) { if (ret < 0) ret = -errno; str = "data"; goto err; } remain -= ret; } return; err: if (ret < 0) printk(UM_KERN_ERR "read_output - read of %s failed, " "errno = %d\n", str, -ret); else printk(UM_KERN_ERR "read_output - read of %s failed, read only " "%d of %d bytes\n", str, ret, expected); } int net_read(int fd, void *buf, int len) { int n; n = read(fd, buf, len); if ((n < 0) && (errno == EAGAIN)) return 0; else if (n == 0) return -ENOTCONN; return n; } int net_recvfrom(int fd, void *buf, int len) { int n; CATCH_EINTR(n = recvfrom(fd, buf, len, 0, NULL, NULL)); if (n < 0) { if (errno == EAGAIN) return 0; return -errno; } else if (n == 0) return -ENOTCONN; return n; } int net_write(int fd, void *buf, int len) { int n; n = write(fd, buf, len); if ((n < 0) && (errno == EAGAIN)) return 0; else if (n == 0) return -ENOTCONN; return n; } int net_send(int fd, void *buf, int len) { int n; CATCH_EINTR(n = send(fd, buf, len, 0)); if (n < 0) { if (errno == EAGAIN) return 0; return -errno; } else if (n == 0) return -ENOTCONN; return n; } int net_sendto(int fd, void *buf, int len, void *to, int sock_len) { int n; CATCH_EINTR(n = sendto(fd, buf, len, 0, (struct sockaddr *) to, sock_len)); if (n < 0) { if (errno == EAGAIN) return 0; return -errno; } else if (n == 0) return -ENOTCONN; return n; } struct change_pre_exec_data { int close_me; int stdout; }; static void change_pre_exec(void *arg) { struct change_pre_exec_data *data = arg; close(data->close_me); dup2(data->stdout, 1); } static int change_tramp(char **argv, char *output, int output_len) { int pid, fds[2], err; struct change_pre_exec_data pe_data; err = os_pipe(fds, 1, 0); if (err < 0) { printk(UM_KERN_ERR "change_tramp - pipe failed, err = %d\n", -err); return err; } pe_data.close_me = fds[0]; pe_data.stdout = fds[1]; pid = run_helper(change_pre_exec, &pe_data, argv); if (pid > 0) /* Avoid hang as we won't get data in failure case. */ read_output(fds[0], output, output_len); close(fds[0]); close(fds[1]); if (pid > 0) helper_wait(pid, 0, "change_tramp"); return pid; } static void change(char *dev, char *what, unsigned char *addr, unsigned char *netmask) { char addr_buf[sizeof("255.255.255.255\0")]; char netmask_buf[sizeof("255.255.255.255\0")]; char version[sizeof("nnnnn\0")]; char *argv[] = { "uml_net", version, what, dev, addr_buf, netmask_buf, NULL }; char *output; int output_len, pid; sprintf(version, "%d", UML_NET_VERSION); sprintf(addr_buf, "%d.%d.%d.%d", addr[0], addr[1], addr[2], addr[3]); sprintf(netmask_buf, "%d.%d.%d.%d", netmask[0], netmask[1], netmask[2], netmask[3]); output_len = UM_KERN_PAGE_SIZE; output = kmalloc(output_len, UM_GFP_KERNEL); if (output == NULL) printk(UM_KERN_ERR "change : failed to allocate output " "buffer\n"); pid = change_tramp(argv, output, output_len); if (pid < 0) return; if (output != NULL) { printk("%s", output); kfree(output); } } void open_addr(unsigned char *addr, unsigned char *netmask, void *arg) { change(arg, "add", addr, netmask); } void close_addr(unsigned char *addr, unsigned char *netmask, void *arg) { change(arg, "del", addr, netmask); } char *split_if_spec(char *str, ...) { char **arg, *end; va_list ap; va_start(ap, str); while ((arg = va_arg(ap, char **)) != NULL) { if (*str == '\0') return NULL; end = strchr(str, ','); if (end != str) *arg = str; if (end == NULL) return NULL; *end++ = '\0'; str = end; } va_end(ap); return str; }