diff options
Diffstat (limited to 'arch/um/drivers/vector_user.c')
-rw-r--r-- | arch/um/drivers/vector_user.c | 858 |
1 files changed, 858 insertions, 0 deletions
diff --git a/arch/um/drivers/vector_user.c b/arch/um/drivers/vector_user.c new file mode 100644 index 0000000000..c719e1ec46 --- /dev/null +++ b/arch/um/drivers/vector_user.c @@ -0,0 +1,858 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2001 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) + */ + +#include <stdbool.h> +#include <stdio.h> +#include <unistd.h> +#include <stdarg.h> +#include <errno.h> +#include <stddef.h> +#include <string.h> +#include <sys/ioctl.h> +#include <net/if.h> +#include <linux/if_tun.h> +#include <arpa/inet.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <netinet/ip.h> +#include <linux/if_ether.h> +#include <linux/if_packet.h> +#include <sys/wait.h> +#include <sys/uio.h> +#include <linux/virtio_net.h> +#include <netdb.h> +#include <stdlib.h> +#include <os.h> +#include <limits.h> +#include <um_malloc.h> +#include "vector_user.h" + +#define ID_GRE 0 +#define ID_L2TPV3 1 +#define ID_BESS 2 +#define ID_MAX 2 + +#define TOKEN_IFNAME "ifname" +#define TOKEN_SCRIPT "ifup" + +#define TRANS_RAW "raw" +#define TRANS_RAW_LEN strlen(TRANS_RAW) + +#define TRANS_FD "fd" +#define TRANS_FD_LEN strlen(TRANS_FD) + +#define VNET_HDR_FAIL "could not enable vnet headers on fd %d" +#define TUN_GET_F_FAIL "tapraw: TUNGETFEATURES failed: %s" +#define L2TPV3_BIND_FAIL "l2tpv3_open : could not bind socket err=%i" +#define UNIX_BIND_FAIL "unix_open : could not bind socket err=%i" +#define BPF_ATTACH_FAIL "Failed to attach filter size %d prog %px to %d, err %d\n" +#define BPF_DETACH_FAIL "Failed to detach filter size %d prog %px to %d, err %d\n" + +#define MAX_UN_LEN 107 + +static const char padchar[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"; +static const char *template = "tapXXXXXX"; + +/* This is very ugly and brute force lookup, but it is done + * only once at initialization so not worth doing hashes or + * anything more intelligent + */ + +char *uml_vector_fetch_arg(struct arglist *ifspec, char *token) +{ + int i; + + for (i = 0; i < ifspec->numargs; i++) { + if (strcmp(ifspec->tokens[i], token) == 0) + return ifspec->values[i]; + } + return NULL; + +} + +struct arglist *uml_parse_vector_ifspec(char *arg) +{ + struct arglist *result; + int pos, len; + bool parsing_token = true, next_starts = true; + + if (arg == NULL) + return NULL; + result = uml_kmalloc(sizeof(struct arglist), UM_GFP_KERNEL); + if (result == NULL) + return NULL; + result->numargs = 0; + len = strlen(arg); + for (pos = 0; pos < len; pos++) { + if (next_starts) { + if (parsing_token) { + result->tokens[result->numargs] = arg + pos; + } else { + result->values[result->numargs] = arg + pos; + result->numargs++; + } + next_starts = false; + } + if (*(arg + pos) == '=') { + if (parsing_token) + parsing_token = false; + else + goto cleanup; + next_starts = true; + (*(arg + pos)) = '\0'; + } + if (*(arg + pos) == ',') { + parsing_token = true; + next_starts = true; + (*(arg + pos)) = '\0'; + } + } + return result; +cleanup: + printk(UM_KERN_ERR "vector_setup - Couldn't parse '%s'\n", arg); + kfree(result); + return NULL; +} + +/* + * Socket/FD configuration functions. These return an structure + * of rx and tx descriptors to cover cases where these are not + * the same (f.e. read via raw socket and write via tap). + */ + +#define PATH_NET_TUN "/dev/net/tun" + + +static int create_tap_fd(char *iface) +{ + struct ifreq ifr; + int fd = -1; + int err = -ENOMEM, offload; + + fd = open(PATH_NET_TUN, O_RDWR); + if (fd < 0) { + printk(UM_KERN_ERR "uml_tap: failed to open tun device\n"); + goto tap_fd_cleanup; + } + memset(&ifr, 0, sizeof(ifr)); + ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_VNET_HDR; + strscpy(ifr.ifr_name, iface, sizeof(ifr.ifr_name)); + + err = ioctl(fd, TUNSETIFF, (void *) &ifr); + if (err != 0) { + printk(UM_KERN_ERR "uml_tap: failed to select tap interface\n"); + goto tap_fd_cleanup; + } + + offload = TUN_F_CSUM | TUN_F_TSO4 | TUN_F_TSO6; + ioctl(fd, TUNSETOFFLOAD, offload); + return fd; +tap_fd_cleanup: + if (fd >= 0) + os_close_file(fd); + return err; +} + +static int create_raw_fd(char *iface, int flags, int proto) +{ + struct ifreq ifr; + int fd = -1; + struct sockaddr_ll sock; + int err = -ENOMEM; + + fd = socket(AF_PACKET, SOCK_RAW, flags); + if (fd == -1) { + err = -errno; + goto raw_fd_cleanup; + } + memset(&ifr, 0, sizeof(ifr)); + strscpy(ifr.ifr_name, iface, sizeof(ifr.ifr_name)); + if (ioctl(fd, SIOCGIFINDEX, (void *) &ifr) < 0) { + err = -errno; + goto raw_fd_cleanup; + } + + sock.sll_family = AF_PACKET; + sock.sll_protocol = htons(proto); + sock.sll_ifindex = ifr.ifr_ifindex; + + if (bind(fd, + (struct sockaddr *) &sock, sizeof(struct sockaddr_ll)) < 0) { + err = -errno; + goto raw_fd_cleanup; + } + return fd; +raw_fd_cleanup: + printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err); + if (fd >= 0) + os_close_file(fd); + return err; +} + + +static struct vector_fds *user_init_tap_fds(struct arglist *ifspec) +{ + int fd = -1, i; + char *iface; + struct vector_fds *result = NULL; + bool dynamic = false; + char dynamic_ifname[IFNAMSIZ]; + char *argv[] = {NULL, NULL, NULL, NULL}; + + iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME); + if (iface == NULL) { + dynamic = true; + iface = dynamic_ifname; + srand(getpid()); + } + + result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL); + if (result == NULL) { + printk(UM_KERN_ERR "uml_tap: failed to allocate file descriptors\n"); + goto tap_cleanup; + } + result->rx_fd = -1; + result->tx_fd = -1; + result->remote_addr = NULL; + result->remote_addr_size = 0; + + /* TAP */ + do { + if (dynamic) { + strcpy(iface, template); + for (i = 0; i < strlen(iface); i++) { + if (iface[i] == 'X') { + iface[i] = padchar[rand() % strlen(padchar)]; + } + } + } + fd = create_tap_fd(iface); + if ((fd < 0) && (!dynamic)) { + printk(UM_KERN_ERR "uml_tap: failed to create tun interface\n"); + goto tap_cleanup; + } + result->tx_fd = fd; + result->rx_fd = fd; + } while (fd < 0); + + argv[0] = uml_vector_fetch_arg(ifspec, TOKEN_SCRIPT); + if (argv[0]) { + argv[1] = iface; + run_helper(NULL, NULL, argv); + } + + return result; +tap_cleanup: + printk(UM_KERN_ERR "user_init_tap: init failed, error %d", fd); + kfree(result); + return NULL; +} + +static struct vector_fds *user_init_hybrid_fds(struct arglist *ifspec) +{ + char *iface; + struct vector_fds *result = NULL; + char *argv[] = {NULL, NULL, NULL, NULL}; + + iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME); + if (iface == NULL) { + printk(UM_KERN_ERR "uml_tap: failed to parse interface spec\n"); + goto hybrid_cleanup; + } + + result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL); + if (result == NULL) { + printk(UM_KERN_ERR "uml_tap: failed to allocate file descriptors\n"); + goto hybrid_cleanup; + } + result->rx_fd = -1; + result->tx_fd = -1; + result->remote_addr = NULL; + result->remote_addr_size = 0; + + /* TAP */ + + result->tx_fd = create_tap_fd(iface); + if (result->tx_fd < 0) { + printk(UM_KERN_ERR "uml_tap: failed to create tun interface: %i\n", result->tx_fd); + goto hybrid_cleanup; + } + + /* RAW */ + + result->rx_fd = create_raw_fd(iface, ETH_P_ALL, ETH_P_ALL); + if (result->rx_fd == -1) { + printk(UM_KERN_ERR + "uml_tap: failed to create paired raw socket: %i\n", result->rx_fd); + goto hybrid_cleanup; + } + + argv[0] = uml_vector_fetch_arg(ifspec, TOKEN_SCRIPT); + if (argv[0]) { + argv[1] = iface; + run_helper(NULL, NULL, argv); + } + return result; +hybrid_cleanup: + printk(UM_KERN_ERR "user_init_hybrid: init failed"); + kfree(result); + return NULL; +} + +static struct vector_fds *user_init_unix_fds(struct arglist *ifspec, int id) +{ + int fd = -1; + int socktype; + char *src, *dst; + struct vector_fds *result = NULL; + struct sockaddr_un *local_addr = NULL, *remote_addr = NULL; + + src = uml_vector_fetch_arg(ifspec, "src"); + dst = uml_vector_fetch_arg(ifspec, "dst"); + result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL); + if (result == NULL) { + printk(UM_KERN_ERR "unix open:cannot allocate remote addr"); + goto unix_cleanup; + } + remote_addr = uml_kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL); + if (remote_addr == NULL) { + printk(UM_KERN_ERR "unix open:cannot allocate remote addr"); + goto unix_cleanup; + } + + switch (id) { + case ID_BESS: + socktype = SOCK_SEQPACKET; + if ((src != NULL) && (strlen(src) <= MAX_UN_LEN)) { + local_addr = uml_kmalloc(sizeof(struct sockaddr_un), UM_GFP_KERNEL); + if (local_addr == NULL) { + printk(UM_KERN_ERR "bess open:cannot allocate local addr"); + goto unix_cleanup; + } + local_addr->sun_family = AF_UNIX; + memcpy(local_addr->sun_path, src, strlen(src) + 1); + } + if ((dst == NULL) || (strlen(dst) > MAX_UN_LEN)) + goto unix_cleanup; + remote_addr->sun_family = AF_UNIX; + memcpy(remote_addr->sun_path, dst, strlen(dst) + 1); + break; + default: + printk(KERN_ERR "Unsupported unix socket type\n"); + return NULL; + } + + fd = socket(AF_UNIX, socktype, 0); + if (fd == -1) { + printk(UM_KERN_ERR + "unix open: could not open socket, error = %d", + -errno + ); + goto unix_cleanup; + } + if (local_addr != NULL) { + if (bind(fd, (struct sockaddr *) local_addr, sizeof(struct sockaddr_un))) { + printk(UM_KERN_ERR UNIX_BIND_FAIL, errno); + goto unix_cleanup; + } + } + switch (id) { + case ID_BESS: + if (connect(fd, (const struct sockaddr *) remote_addr, sizeof(struct sockaddr_un)) < 0) { + printk(UM_KERN_ERR "bess open:cannot connect to %s %i", remote_addr->sun_path, -errno); + goto unix_cleanup; + } + break; + } + result->rx_fd = fd; + result->tx_fd = fd; + result->remote_addr_size = sizeof(struct sockaddr_un); + result->remote_addr = remote_addr; + return result; +unix_cleanup: + if (fd >= 0) + os_close_file(fd); + kfree(remote_addr); + kfree(result); + return NULL; +} + +static int strtofd(const char *nptr) +{ + long fd; + char *endptr; + + if (nptr == NULL) + return -1; + + errno = 0; + fd = strtol(nptr, &endptr, 10); + if (nptr == endptr || + errno != 0 || + *endptr != '\0' || + fd < 0 || + fd > INT_MAX) { + return -1; + } + return fd; +} + +static struct vector_fds *user_init_fd_fds(struct arglist *ifspec) +{ + int fd = -1; + char *fdarg = NULL; + struct vector_fds *result = NULL; + + fdarg = uml_vector_fetch_arg(ifspec, "fd"); + fd = strtofd(fdarg); + if (fd == -1) { + printk(UM_KERN_ERR "fd open: bad or missing fd argument"); + goto fd_cleanup; + } + + result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL); + if (result == NULL) { + printk(UM_KERN_ERR "fd open: allocation failed"); + goto fd_cleanup; + } + + result->rx_fd = fd; + result->tx_fd = fd; + result->remote_addr_size = 0; + result->remote_addr = NULL; + return result; + +fd_cleanup: + if (fd >= 0) + os_close_file(fd); + kfree(result); + return NULL; +} + +static struct vector_fds *user_init_raw_fds(struct arglist *ifspec) +{ + int rxfd = -1, txfd = -1; + int err = -ENOMEM; + char *iface; + struct vector_fds *result = NULL; + char *argv[] = {NULL, NULL, NULL, NULL}; + + iface = uml_vector_fetch_arg(ifspec, TOKEN_IFNAME); + if (iface == NULL) + goto raw_cleanup; + + rxfd = create_raw_fd(iface, ETH_P_ALL, ETH_P_ALL); + if (rxfd == -1) { + err = -errno; + goto raw_cleanup; + } + txfd = create_raw_fd(iface, 0, ETH_P_IP); /* Turn off RX on this fd */ + if (txfd == -1) { + err = -errno; + goto raw_cleanup; + } + result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL); + if (result != NULL) { + result->rx_fd = rxfd; + result->tx_fd = txfd; + result->remote_addr = NULL; + result->remote_addr_size = 0; + } + argv[0] = uml_vector_fetch_arg(ifspec, TOKEN_SCRIPT); + if (argv[0]) { + argv[1] = iface; + run_helper(NULL, NULL, argv); + } + return result; +raw_cleanup: + printk(UM_KERN_ERR "user_init_raw: init failed, error %d", err); + kfree(result); + return NULL; +} + + +bool uml_raw_enable_qdisc_bypass(int fd) +{ + int optval = 1; + + if (setsockopt(fd, + SOL_PACKET, PACKET_QDISC_BYPASS, + &optval, sizeof(optval)) != 0) { + return false; + } + return true; +} + +bool uml_raw_enable_vnet_headers(int fd) +{ + int optval = 1; + + if (setsockopt(fd, + SOL_PACKET, PACKET_VNET_HDR, + &optval, sizeof(optval)) != 0) { + printk(UM_KERN_INFO VNET_HDR_FAIL, fd); + return false; + } + return true; +} +bool uml_tap_enable_vnet_headers(int fd) +{ + unsigned int features; + int len = sizeof(struct virtio_net_hdr); + + if (ioctl(fd, TUNGETFEATURES, &features) == -1) { + printk(UM_KERN_INFO TUN_GET_F_FAIL, strerror(errno)); + return false; + } + if ((features & IFF_VNET_HDR) == 0) { + printk(UM_KERN_INFO "tapraw: No VNET HEADER support"); + return false; + } + ioctl(fd, TUNSETVNETHDRSZ, &len); + return true; +} + +static struct vector_fds *user_init_socket_fds(struct arglist *ifspec, int id) +{ + int err = -ENOMEM; + int fd = -1, gairet; + struct addrinfo srchints; + struct addrinfo dsthints; + bool v6, udp; + char *value; + char *src, *dst, *srcport, *dstport; + struct addrinfo *gairesult = NULL; + struct vector_fds *result = NULL; + + + value = uml_vector_fetch_arg(ifspec, "v6"); + v6 = false; + udp = false; + if (value != NULL) { + if (strtol((const char *) value, NULL, 10) > 0) + v6 = true; + } + + value = uml_vector_fetch_arg(ifspec, "udp"); + if (value != NULL) { + if (strtol((const char *) value, NULL, 10) > 0) + udp = true; + } + src = uml_vector_fetch_arg(ifspec, "src"); + dst = uml_vector_fetch_arg(ifspec, "dst"); + srcport = uml_vector_fetch_arg(ifspec, "srcport"); + dstport = uml_vector_fetch_arg(ifspec, "dstport"); + + memset(&dsthints, 0, sizeof(dsthints)); + + if (v6) + dsthints.ai_family = AF_INET6; + else + dsthints.ai_family = AF_INET; + + switch (id) { + case ID_GRE: + dsthints.ai_socktype = SOCK_RAW; + dsthints.ai_protocol = IPPROTO_GRE; + break; + case ID_L2TPV3: + if (udp) { + dsthints.ai_socktype = SOCK_DGRAM; + dsthints.ai_protocol = 0; + } else { + dsthints.ai_socktype = SOCK_RAW; + dsthints.ai_protocol = IPPROTO_L2TP; + } + break; + default: + printk(KERN_ERR "Unsupported socket type\n"); + return NULL; + } + memcpy(&srchints, &dsthints, sizeof(struct addrinfo)); + + gairet = getaddrinfo(src, srcport, &dsthints, &gairesult); + if ((gairet != 0) || (gairesult == NULL)) { + printk(UM_KERN_ERR + "socket_open : could not resolve src, error = %s", + gai_strerror(gairet) + ); + return NULL; + } + fd = socket(gairesult->ai_family, + gairesult->ai_socktype, gairesult->ai_protocol); + if (fd == -1) { + printk(UM_KERN_ERR + "socket_open : could not open socket, error = %d", + -errno + ); + goto cleanup; + } + if (bind(fd, + (struct sockaddr *) gairesult->ai_addr, + gairesult->ai_addrlen)) { + printk(UM_KERN_ERR L2TPV3_BIND_FAIL, errno); + goto cleanup; + } + + if (gairesult != NULL) + freeaddrinfo(gairesult); + + gairesult = NULL; + + gairet = getaddrinfo(dst, dstport, &dsthints, &gairesult); + if ((gairet != 0) || (gairesult == NULL)) { + printk(UM_KERN_ERR + "socket_open : could not resolve dst, error = %s", + gai_strerror(gairet) + ); + return NULL; + } + + result = uml_kmalloc(sizeof(struct vector_fds), UM_GFP_KERNEL); + if (result != NULL) { + result->rx_fd = fd; + result->tx_fd = fd; + result->remote_addr = uml_kmalloc( + gairesult->ai_addrlen, UM_GFP_KERNEL); + if (result->remote_addr == NULL) + goto cleanup; + result->remote_addr_size = gairesult->ai_addrlen; + memcpy( + result->remote_addr, + gairesult->ai_addr, + gairesult->ai_addrlen + ); + } + freeaddrinfo(gairesult); + return result; +cleanup: + if (gairesult != NULL) + freeaddrinfo(gairesult); + printk(UM_KERN_ERR "user_init_socket: init failed, error %d", err); + if (fd >= 0) + os_close_file(fd); + if (result != NULL) { + kfree(result->remote_addr); + kfree(result); + } + return NULL; +} + +struct vector_fds *uml_vector_user_open( + int unit, + struct arglist *parsed +) +{ + char *transport; + + if (parsed == NULL) { + printk(UM_KERN_ERR "no parsed config for unit %d\n", unit); + return NULL; + } + transport = uml_vector_fetch_arg(parsed, "transport"); + if (transport == NULL) { + printk(UM_KERN_ERR "missing transport for unit %d\n", unit); + return NULL; + } + if (strncmp(transport, TRANS_RAW, TRANS_RAW_LEN) == 0) + return user_init_raw_fds(parsed); + if (strncmp(transport, TRANS_HYBRID, TRANS_HYBRID_LEN) == 0) + return user_init_hybrid_fds(parsed); + if (strncmp(transport, TRANS_TAP, TRANS_TAP_LEN) == 0) + return user_init_tap_fds(parsed); + if (strncmp(transport, TRANS_GRE, TRANS_GRE_LEN) == 0) + return user_init_socket_fds(parsed, ID_GRE); + if (strncmp(transport, TRANS_L2TPV3, TRANS_L2TPV3_LEN) == 0) + return user_init_socket_fds(parsed, ID_L2TPV3); + if (strncmp(transport, TRANS_BESS, TRANS_BESS_LEN) == 0) + return user_init_unix_fds(parsed, ID_BESS); + if (strncmp(transport, TRANS_FD, TRANS_FD_LEN) == 0) + return user_init_fd_fds(parsed); + return NULL; +} + + +int uml_vector_sendmsg(int fd, void *hdr, int flags) +{ + int n; + + CATCH_EINTR(n = sendmsg(fd, (struct msghdr *) hdr, flags)); + if ((n < 0) && (errno == EAGAIN)) + return 0; + if (n >= 0) + return n; + else + return -errno; +} + +int uml_vector_recvmsg(int fd, void *hdr, int flags) +{ + int n; + struct msghdr *msg = (struct msghdr *) hdr; + + CATCH_EINTR(n = readv(fd, msg->msg_iov, msg->msg_iovlen)); + if ((n < 0) && (errno == EAGAIN)) + return 0; + if (n >= 0) + return n; + else + return -errno; +} + +int uml_vector_writev(int fd, void *hdr, int iovcount) +{ + int n; + + CATCH_EINTR(n = writev(fd, (struct iovec *) hdr, iovcount)); + if ((n < 0) && ((errno == EAGAIN) || (errno == ENOBUFS))) + return 0; + if (n >= 0) + return n; + else + return -errno; +} + +int uml_vector_sendmmsg( + int fd, + void *msgvec, + unsigned int vlen, + unsigned int flags) +{ + int n; + + CATCH_EINTR(n = sendmmsg(fd, (struct mmsghdr *) msgvec, vlen, flags)); + if ((n < 0) && ((errno == EAGAIN) || (errno == ENOBUFS))) + return 0; + if (n >= 0) + return n; + else + return -errno; +} + +int uml_vector_recvmmsg( + int fd, + void *msgvec, + unsigned int vlen, + unsigned int flags) +{ + int n; + + CATCH_EINTR( + n = recvmmsg(fd, (struct mmsghdr *) msgvec, vlen, flags, 0)); + if ((n < 0) && (errno == EAGAIN)) + return 0; + if (n >= 0) + return n; + else + return -errno; +} +int uml_vector_attach_bpf(int fd, void *bpf) +{ + struct sock_fprog *prog = bpf; + + int err = setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, bpf, sizeof(struct sock_fprog)); + + if (err < 0) + printk(KERN_ERR BPF_ATTACH_FAIL, prog->len, prog->filter, fd, -errno); + return err; +} + +int uml_vector_detach_bpf(int fd, void *bpf) +{ + struct sock_fprog *prog = bpf; + + int err = setsockopt(fd, SOL_SOCKET, SO_DETACH_FILTER, bpf, sizeof(struct sock_fprog)); + if (err < 0) + printk(KERN_ERR BPF_DETACH_FAIL, prog->len, prog->filter, fd, -errno); + return err; +} +void *uml_vector_default_bpf(const void *mac) +{ + struct sock_filter *bpf; + uint32_t *mac1 = (uint32_t *)(mac + 2); + uint16_t *mac2 = (uint16_t *) mac; + struct sock_fprog *bpf_prog; + + bpf_prog = uml_kmalloc(sizeof(struct sock_fprog), UM_GFP_KERNEL); + if (bpf_prog) { + bpf_prog->len = DEFAULT_BPF_LEN; + bpf_prog->filter = NULL; + } else { + return NULL; + } + bpf = uml_kmalloc( + sizeof(struct sock_filter) * DEFAULT_BPF_LEN, UM_GFP_KERNEL); + if (bpf) { + bpf_prog->filter = bpf; + /* ld [8] */ + bpf[0] = (struct sock_filter){ 0x20, 0, 0, 0x00000008 }; + /* jeq #0xMAC[2-6] jt 2 jf 5*/ + bpf[1] = (struct sock_filter){ 0x15, 0, 3, ntohl(*mac1)}; + /* ldh [6] */ + bpf[2] = (struct sock_filter){ 0x28, 0, 0, 0x00000006 }; + /* jeq #0xMAC[0-1] jt 4 jf 5 */ + bpf[3] = (struct sock_filter){ 0x15, 0, 1, ntohs(*mac2)}; + /* ret #0 */ + bpf[4] = (struct sock_filter){ 0x6, 0, 0, 0x00000000 }; + /* ret #0x40000 */ + bpf[5] = (struct sock_filter){ 0x6, 0, 0, 0x00040000 }; + } else { + kfree(bpf_prog); + bpf_prog = NULL; + } + return bpf_prog; +} + +/* Note - this function requires a valid mac being passed as an arg */ + +void *uml_vector_user_bpf(char *filename) +{ + struct sock_filter *bpf; + struct sock_fprog *bpf_prog; + struct stat statbuf; + int res, ffd = -1; + + if (filename == NULL) + return NULL; + + if (stat(filename, &statbuf) < 0) { + printk(KERN_ERR "Error %d reading bpf file", -errno); + return false; + } + bpf_prog = uml_kmalloc(sizeof(struct sock_fprog), UM_GFP_KERNEL); + if (bpf_prog == NULL) { + printk(KERN_ERR "Failed to allocate bpf prog buffer"); + return NULL; + } + bpf_prog->len = statbuf.st_size / sizeof(struct sock_filter); + bpf_prog->filter = NULL; + ffd = os_open_file(filename, of_read(OPENFLAGS()), 0); + if (ffd < 0) { + printk(KERN_ERR "Error %d opening bpf file", -errno); + goto bpf_failed; + } + bpf = uml_kmalloc(statbuf.st_size, UM_GFP_KERNEL); + if (bpf == NULL) { + printk(KERN_ERR "Failed to allocate bpf buffer"); + goto bpf_failed; + } + bpf_prog->filter = bpf; + res = os_read_file(ffd, bpf, statbuf.st_size); + if (res < statbuf.st_size) { + printk(KERN_ERR "Failed to read bpf program %s, error %d", filename, res); + kfree(bpf); + goto bpf_failed; + } + os_close_file(ffd); + return bpf_prog; +bpf_failed: + if (ffd > 0) + os_close_file(ffd); + kfree(bpf_prog); + return NULL; +} |