diff options
author | Laurent Vivier <laurent@vivier.eu> | 2015-10-28 21:40:45 +0100 |
---|---|---|
committer | Riku Voipio <riku.voipio@linaro.org> | 2016-01-08 15:20:15 +0200 |
commit | 0cf227229bfd288a67fd9d4005ee01ffdb492c70 (patch) | |
tree | 4477c2d229a3fb89acdf810657df3ca02194d5c8 /linux-user/syscall.c | |
parent | 7b36f78274e701ee17db3171ec7e9f732a60f031 (diff) | |
download | qemu-0cf227229bfd288a67fd9d4005ee01ffdb492c70.zip qemu-0cf227229bfd288a67fd9d4005ee01ffdb492c70.tar.gz qemu-0cf227229bfd288a67fd9d4005ee01ffdb492c70.tar.bz2 |
linux-user: manage bind with a socket of SOCK_PACKET type.
This is obsolete, but if we want to use dhcp with an old distro (like debian
etch), we need it. Some users (like dhclient) use SOCK_PACKET with AF_PACKET
and the kernel allows that.
packet(7)
In Linux 2.0, the only way to get a packet socket was by calling
socket(AF_INET, SOCK_PACKET, protocol). This is still supported but
strongly deprecated. The main difference between the two methods is
that SOCK_PACKET uses the old struct sockaddr_pkt to specify an inter‐
face, which doesn't provide physical layer independence.
struct sockaddr_pkt {
unsigned short spkt_family;
unsigned char spkt_device[14];
unsigned short spkt_protocol;
};
spkt_family contains the device type, spkt_protocol is the IEEE 802.3
protocol type as defined in <sys/if_ether.h> and spkt_device is the
device name as a null-terminated string, for example, eth0.
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Diffstat (limited to 'linux-user/syscall.c')
-rw-r--r-- | linux-user/syscall.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 3484132..94d64fa 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -2090,6 +2090,30 @@ static int sock_flags_fixup(int fd, int target_type) return fd; } +static abi_long packet_target_to_host_sockaddr(void *host_addr, + abi_ulong target_addr, + socklen_t len) +{ + struct sockaddr *addr = host_addr; + struct target_sockaddr *target_saddr; + + target_saddr = lock_user(VERIFY_READ, target_addr, len, 1); + if (!target_saddr) { + return -TARGET_EFAULT; + } + + memcpy(addr, target_saddr, len); + addr->sa_family = tswap16(target_saddr->sa_family); + /* spkt_protocol is big-endian */ + + unlock_user(target_saddr, target_addr, 0); + return 0; +} + +static TargetFdTrans target_packet_trans = { + .target_to_host_addr = packet_target_to_host_sockaddr, +}; + /* do_socket() Must return target values and target errnos. */ static abi_long do_socket(int domain, int type, int protocol) { @@ -2112,6 +2136,12 @@ static abi_long do_socket(int domain, int type, int protocol) ret = get_errno(socket(domain, type, protocol)); if (ret >= 0) { ret = sock_flags_fixup(ret, target_type); + if (type == SOCK_PACKET) { + /* Manage an obsolete case : + * if socket type is SOCK_PACKET, bind by name + */ + fd_trans_register(ret, &target_packet_trans); + } } return ret; } |