/* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * Generic socket support routines. Memory allocators, socket lock/release * handler for protocols to use and generic option handler. * * * Version: $Id: sock.c,v 1.117 2002/02/01 22:01:03 davem Exp $ * * Authors: Ross Biro * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> * Florian La Roche, <flla@stud.uni-sb.de> * Alan Cox, <A.Cox@swansea.ac.uk> * * Fixes: * Alan Cox : Numerous verify_area() problems * Alan Cox : Connecting on a connecting socket * now returns an error for tcp. * Alan Cox : sock->protocol is set correctly. * and is not sometimes left as 0. * Alan Cox : connect handles icmp errors on a * connect properly. Unfortunately there * is a restart syscall nasty there. I * can't match BSD without hacking the C * library. Ideas urgently sought! * Alan Cox : Disallow bind() to addresses that are * not ours - especially broadcast ones!! * Alan Cox : Socket 1024 _IS_ ok for users. (fencepost) * Alan Cox : sock_wfree/sock_rfree don't destroy sockets, * instead they leave that for the DESTROY timer. * Alan Cox : Clean up error flag in accept * Alan Cox : TCP ack handling is buggy, the DESTROY timer * was buggy. Put a remove_sock() in the handler * for memory when we hit 0. Also altered the timer * code. The ACK stuff can wait and needs major * TCP layer surgery. * Alan Cox : Fixed TCP ack bug, removed remove sock * and fixed timer/inet_bh race. * Alan Cox : Added zapped flag for TCP * Alan Cox : Move kfree_skb into skbuff.c and tidied up surplus code * Alan Cox : for new sk_buff allocations wmalloc/rmalloc now call alloc_skb * Alan Cox : kfree_s calls now are kfree_skbmem so we can track skb resources * Alan Cox : Supports socket option broadcast now as does udp. Packet and raw need fixing. * Alan Cox : Added RCVBUF,SNDBUF size setting. It suddenly occurred to me how easy it was so... * Rick Sladkey : Relaxed UDP rules for matching packets. * C.E.Hawkins : IFF_PROMISC/SIOCGHWADDR support * Pauline Middelink : identd support * Alan Cox : Fixed connect() taking signals I think. * Alan Cox : SO_LINGER supported * Alan Cox : Error reporting fixes * Anonymous : inet_create tidied up (sk->reuse setting) * Alan Cox : inet sockets don't set sk->type! * Alan Cox : Split socket option code * Alan Cox : Callbacks * Alan Cox : Nagle flag for Charles & Johannes stuff * Alex : Removed restriction on inet fioctl * Alan Cox : Splitting INET from NET core * Alan Cox : Fixed bogus SO_TYPE handling in getsockopt() * Adam Caldwell : Missing return in SO_DONTROUTE/SO_DEBUG code * Alan Cox : Split IP from generic code * Alan Cox : New kfree_skbmem() * Alan Cox : Make SO_DEBUG superuser only. * Alan Cox : Allow anyone to clear SO_DEBUG * (compatibility fix) * Alan Cox : Added optimistic memory grabbing for AF_UNIX throughput. * Alan Cox : Allocator for a socket is settable. * Alan Cox : SO_ERROR includes soft errors. * Alan Cox : Allow NULL arguments on some SO_ opts * Alan Cox : Generic socket allocation to make hooks * easier (suggested by Craig Metz). * Michael Pall : SO_ERROR returns positive errno again * Steve Whitehouse: Added default destructor to free * protocol private data. * Steve Whitehouse: Added various other default routines * common to several socket families. * Chris Evans : Call suser() check last on F_SETOWN * Jay Schulist : Added SO_ATTACH_FILTER and SO_DETACH_FILTER. * Andi Kleen : Add sock_kmalloc()/sock_kfree_s() * Andi Kleen : Fix write_space callback * Chris Evans : Security fixes - signedness again * Arnaldo C. Melo : cleanups, use skb_queue_purge * * To Fix: * * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include <linux/config.h> #include <linux/errno.h> #include <linux/types.h> #include <linux/socket.h> #include <linux/in.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/sched.h> #include <linux/timer.h> #include <linux/string.h> #include <linux/sockios.h> #include <linux/net.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/interrupt.h> #include <linux/poll.h> #include <linux/tcp.h> #include <linux/init.h> #include <asm/uaccess.h> #include <asm/system.h> #include <linux/netdevice.h> #include <net/protocol.h> #include <linux/skbuff.h> #include <net/request_sock.h> #include <net/sock.h> #include <net/xfrm.h> #include <linux/ipsec.h> #include <linux/filter.h> #ifdef CONFIG_INET #include <net/tcp.h> #endif /* Take into consideration the size of the struct sk_buff overhead in the * determination of these values, since that is non-constant across * platforms. This makes socket queueing behavior and performance * not depend upon such differences. */ #define _SK_MEM_PACKETS 256 #define _SK_MEM_OVERHEAD (sizeof(struct sk_buff) + 256) #define SK_WMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) #define SK_RMEM_MAX (_SK_MEM_OVERHEAD * _SK_MEM_PACKETS) /* Run time adjustable parameters. */ __u32 sysctl_wmem_max = SK_WMEM_MAX; __u32 sysctl_rmem_max = SK_RMEM_MAX; __u32 sysctl_wmem_default = SK_WMEM_MAX; __u32 sysctl_rmem_default = SK_RMEM_MAX; /* Maximal space eaten by iovec or ancilliary data plus some space */ int sysctl_optmem_max = sizeof(unsigned long)*(2*UIO_MAXIOV + 512); static int sock_set_timeout(long *timeo_p, char __user *optval, int optlen) { struct timeval tv; if (optlen < sizeof(tv)) return -EINVAL; if (copy_from_user(&tv, optval, sizeof(tv))) return -EFAULT; *timeo_p = MAX_SCHEDULE_TIMEOUT; if (tv.tv_sec == 0 && tv.tv_usec == 0) return 0; if (tv.tv_sec < (MAX_SCHEDULE_TIMEOUT/HZ - 1)) *timeo_p = tv.tv_sec*HZ + (tv.tv_usec+(1000000/HZ-1))/(1000000/HZ); return 0; } static void sock_warn_obsolete_bsdism(const char *name) { static int warned; static char warncomm[TASK_COMM_LEN]; if (strcmp(warncomm, current->comm) && warned < 5) { strcpy(warncomm, current->comm); printk(KERN_WARNING "process `%s' is using obsolete " "%s SO_BSDCOMPAT\n", warncomm, name); warned++; } } static void sock_disable_timestamp(struct sock *sk) { if (sock_flag(sk, SOCK_TIMESTAMP)) { sock_reset_flag(sk, SOCK_TIMESTAMP); net_disable_timestamp(); } } /* * This is meant for all protocols to use and covers goings on * at the socket level. Everything here is generic. */ int sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen) { struct sock *sk=sock->sk; struct sk_filter *filter; int val; int valbool; struct linger ling; int ret = 0; /* * Options without arguments */ #ifdef SO_DONTLINGER /* Compatibility item... */ if (optname == SO_DONTLINGER) { lock_sock(sk); sock_reset_flag(sk, SOCK_LINGER); release_sock(sk); return 0; } #endif if(optlen<sizeof(int)) return(-EINVAL); if (get_user(val, (int __user *)optval)) return -EFAULT; valbool = val?1:0; lock_sock(sk); switch(optname) { case SO_DEBUG: if(val && !capable(CAP_NET_ADMIN)) { ret = -EACCES; } else if (valbool) sock_set_flag(sk, SOCK_DBG); else sock_reset_flag(sk, SOCK_DBG); break; case SO_REUSEADDR: sk->sk_reuse = valbool; break; case SO_TYPE: case SO_ERROR: ret = -ENOPROTOOPT; break; case SO_DONTROUTE: if (valbool) sock_set_flag(sk, SOCK_LOCALROUTE); else sock_reset_flag(sk, SOCK_LOCALROUTE); break; case SO_BROADCAST: sock_valbool_flag(sk, SOCK_BROADCAST, valbool); break; case SO_SNDBUF: /* Don't error on this BSD doesn't and if you think about it this is right. Otherwise apps have to play 'guess the biggest size' games. RCVBUF/SNDBUF are treated in BSD as hints */ if (val > sysctl_wmem_max) val = sysctl_wmem_max; set_sndbuf: sk->sk_userlocks |= SOCK_SNDBUF_LOCK; if ((val * 2) < SOCK_MIN_SNDBUF) sk->sk_sndbuf = SOCK_MIN_SNDBUF; else sk->sk_sndbuf = val * 2; /* * Wake up sending tasks if we * upped the value. */ sk->sk_write_space(sk); break; case SO_SNDBUFFORCE: if (!capable(CAP_NET_ADMIN)) { ret = -EPERM; break; } goto set_sndbuf; case SO_RCVBUF: /* Don't error on this BSD doesn't and if you think about it this is right. Otherwise apps have to play 'guess the biggest size' games. RCVBUF/SNDBUF are treated in BSD as hints */ if (val > sysctl_rmem_max) val = sysctl_rmem_max; set_rcvbuf: sk->sk_userlocks |= SOCK_RCVBUF_LOCK; /* FIXME: is this lower bound the right one? */ if ((val * 2) < SOCK_MIN_RCVBUF) sk->sk_rcvbuf = SOCK_MIN_RCVBUF; else sk->sk_rcvbuf = val * 2; break; case SO_RCVBUFFORCE: if (!capable(CAP_NET_ADMIN)) { ret = -EPERM; break; } goto set_rcvbuf; case SO_KEEPALIVE: #ifdef CONFIG_INET if (sk->sk_protocol == IPPROTO_TCP) tcp_set_keepalive(sk, valbool); #endif sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool); break; case SO_OOBINLINE: sock_valbool_flag(sk, SOCK_URGINLINE, valbool); break; case SO_NO_CHECK: sk->sk_no_check = valbool; break; case SO_PRIORITY: if ((val >= 0 && val <= 6) || capable(CAP_NET_ADMIN)) sk->sk_priority = val; else ret = -EPERM; break; case SO_LINGER: if(optlen<sizeof(ling)) { ret = -EINVAL; /* 1003.1g */ break; } if (copy_from_user(&ling,optval,sizeof(ling))) { ret = -EFAULT; break; } if (!ling.l_onoff) sock_reset_flag(sk, SOCK_LINGER); else { #if (BITS_PER_LONG == 32) if ((unsigned int)ling.l_linger >= MAX_SCHEDULE_TIMEOUT/HZ) sk->sk_lingertime = MAX_SCHEDULE_TIMEOUT; else #endif sk->sk_lingertime = (unsigned int)ling.l_linger * HZ; sock_set_flag(sk, SOCK_LINGER); } break; case SO_BSDCOMPAT: sock_warn_obsolete_bsdism("setsockopt"); break; case SO_PASSCRED: if (valbool) set_bit(SOCK_PASSCRED, &sock->flags); else clear_bit(SOCK_PASSCRED, &sock->flags); break; case SO_TIMESTAMP: if (valbool) { sock_set_flag(sk, SOCK_RCVTSTAMP); sock_enable_timestamp(sk); } else sock_reset_flag(sk, SOCK_RCVTSTAMP); break; case SO_RCVLOWAT: if (val < 0) val = INT_MAX; sk->sk_rcvlowat = val ? : 1; break; case SO_RCVTIMEO: ret = sock_set_timeout(&sk->sk_rcvtimeo, optval, optlen); break; case SO_SNDTIMEO: ret = sock_set_timeout(&sk->sk_sndtimeo, optval, optlen); break; #ifdef CONFIG_NETDEVICES case SO_BINDTODEVICE: { char devname[IFNAMSIZ]; /* Sorry... */ if (!capable(CAP_NET_RAW)) { ret = -EPERM; break; } /* Bind this socket to a particular device like "eth0", * as specified in the passed interface name. If the * name is "" or the option length is zero the socket * is not bound. */ if (!valbool) { sk->sk_bound_dev_if = 0; } else { if (optlen > IFNAMSIZ) optlen = IFNAMSIZ; if (copy_from_user(devname, optval, optlen)) { ret = -EFAULT; break; } /* Remove any cached route for this socket. */ sk_dst_reset(sk); if (devname[0] == '\0') { sk->sk_bound_dev_if = 0; } else { struct net_device *dev = dev_get_by_name(devname); if (!dev) { ret = -ENODEV; break; } sk->sk_bound_dev_if = dev->ifindex; dev_put(dev); } } break; } #endif case SO_ATTACH_FILTER: ret = -EINVAL; if (optlen == sizeof(struct sock_fprog)) { struct sock_fprog fprog; ret = -EFAULT; if (copy_from_user(&fprog, optval, sizeof(fprog))) break; ret = sk_attach_filter(&fprog, sk); } break; case SO_DETACH_FILTER: spin_lock_bh(&sk->sk_lock.slock); filter = sk->sk_filter; if (filter) { sk->sk_filter = NULL; spin_unlock_bh(&sk->sk_lock.slock); sk_filter_release(sk, filter); break; } spin_unlock_bh(&sk->sk_lock.slock); ret = -ENONET; break; /* We implement the SO_SNDLOWAT etc to not be settable (1003.1g 5.3) */ default: ret = -ENOPROTOOPT; break; } release_sock(sk); return ret; } int sock_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen) { struct sock *sk = sock->sk; union { int val; struct linger ling; struct timeval tm; } v; unsigned int lv = sizeof(int); int len; if(get_user(len,optlen)) return -EFAULT; if(len < 0) return -EINVAL; switch(optname) { case SO_DEBUG: v.val = sock_flag(sk, SOCK_DBG); break; case SO_DONTROUTE: v.val = sock_flag(sk, SOCK_LOCALROUTE); break; case SO_BROADCAST: v.val = !!sock_flag(sk, SOCK_BROADCAST); break; case SO_SNDBUF: v.val = sk->sk_sndbuf; break; case SO_RCVBUF: v.val = sk->sk_rcvbuf; break; case SO_REUSEADDR: v.val = sk->sk_reuse; break; case SO_KEEPALIVE: v.val = !!sock_flag(sk, SOCK_KEEPOPEN); break; case SO_TYPE: v.val = sk->sk_type; break; case SO_ERROR: v.val = -sock_error(sk); if(v.val==0) v.val = xchg(&sk->sk_err_soft, 0); break; case SO_OOBINLINE: v.val = !!sock_flag(sk, SOCK_URGINLINE); break; case SO_NO_CHECK: v.val = sk->sk_no_check; break; case SO_PRIORITY: v.val = sk->sk_priority; break; case SO_LINGER: lv = sizeof(v.ling); v.ling.l_onoff = !!sock_flag(sk, SOCK_LINGER); v.ling.l_linger = sk->sk_lingertime / HZ; break; case SO_BSDCOMPAT: sock_warn_obsolete_bsdism("getsockopt"); break; case SO_TIMESTAMP: v.val = sock_flag(sk, SOCK_RCVTSTAMP); break; case SO_RCVTIMEO: lv=sizeof(struct timeval); if (sk->sk_rcvtimeo == MAX_SCHEDULE_TIMEOUT) { v.tm.tv_sec = 0; v.tm.tv_usec = 0; } else { v.tm.tv_sec = sk->sk_rcvtimeo / HZ; v.tm.tv_usec = ((sk->sk_rcvtimeo % HZ) * 1000000) / HZ; } break; case SO_SNDTIMEO: lv=sizeof(struct timeval); if (sk->sk_sndtimeo == MAX_SCHEDULE_TIMEOUT) { v.tm.tv_sec = 0; v.tm.tv_usec = 0; } else { v.tm.tv_sec = sk->sk_sndtimeo / HZ; v.tm.tv_usec = ((sk->sk_sndtimeo % HZ) * 1000000) / HZ; } break; case SO_RCVLOWAT: v.val = sk->sk_rcvlowat; break; case SO_SNDLOWAT: v.val=1; break; case SO_PASSCRED: v.val = test_bit(SOCK_PASSCRED, &sock->flags) ? 1 : 0; break; case SO_PEERCRED: if (len > sizeof(sk->sk_peercred)) len = sizeof(sk->sk_peercred); if (copy_to_user(optval, &sk->sk_peercred, len)) return -EFAULT; goto lenout; case SO_PEERNAME: { char address[128]; if (sock->ops->getname(sock, (struct sockaddr *)address, &lv, 2)) return -ENOTCONN; if (lv < len) return -EINVAL; if (copy_to_user(optval, address, len)) return -EFAULT; goto lenout; } /* Dubious BSD thing... Probably nobody even uses it, but * the UNIX standard wants it for whatever reason... -DaveM */ case SO_ACCEPTCONN: v.val = sk->sk_state == TCP_LISTEN; break; case SO_PEERSEC: return security_socket_getpeersec(sock, optval, optlen, len); default: return(-ENOPROTOOPT); } if (len > lv) len = lv; if (copy_to_user(optval, &v, len)) return -EFAULT; lenout: if (put_user(len, optlen)) return -EFAULT; return 0; } /** * sk_alloc - All socket objects are allocated here * @family: protocol family * @priority: for allocation (%GFP_KERNEL, %GFP_ATOMIC, etc) * @prot: struct proto associated with this new sock instance * @zero_it: if we should zero the newly allocated sock */ struct sock *sk_alloc(int family, gfp_t priority, struct proto *prot, int zero_it) { struct sock *sk = NULL; kmem_cache_t *slab = prot->slab; if (slab != NULL) sk = kmem_cache_alloc(slab, priority); else sk = kmalloc(prot->obj_size, priority); if (sk) { if (zero_it) { memset(sk, 0, prot->obj_size); sk->sk_family = family; /* * See comment in struct sock definition to understand * why we need sk_prot_creator -acme */ sk->sk_prot = sk->sk_prot_creator = prot; sock_lock_init(sk); } if (security_sk_alloc(sk, family, priority)) goto out_free; if (!try_module_get(prot->owner)) goto out_free; } return sk; out_free: if (slab != NULL) kmem_cache_free(slab, sk); else kfree(sk); return NULL; } void sk_free(struct sock *sk) { struct sk_filter *filter; struct module *owner = sk->sk_prot_creator->owner; if (sk->sk_destruct) sk->sk_destruct(sk); filter = sk->sk_filter; if (filter) { sk_filter_release(sk, filter); sk->sk_filter = NULL; } sock_disable_timestamp(sk); if (atomic_read(&sk->sk_omem_alloc)) printk(KERN_DEBUG "%s: optmem leakage (%d bytes) detected.\n", __FUNCTION__, atomic_read(&sk->sk_omem_alloc)); security_sk_free(sk); if (sk->sk_prot_creator->slab != NULL) kmem_cache_free(sk->sk_prot_creator->slab, sk); else kfree(sk); module_put(owner); } struct sock *sk_clone(const struct sock *sk, const gfp_t priority) { struct sock *newsk = sk_alloc(sk->sk_family, priority, sk->sk_prot, 0); if (newsk != NULL) { struct sk_filter *filter; memcpy(newsk, sk, sk->sk_prot->obj_size); /* SANITY */ sk_node_init(&newsk->sk_node); sock_lock_init(newsk); bh_lock_sock(newsk); atomic_set(&newsk->sk_rmem_alloc, 0); atomic_set(&newsk->sk_wmem_alloc, 0); atomic_set(&newsk->sk_omem_alloc, 0); skb_queue_head_init(&newsk->sk_receive_queue); skb_queue_head_init(&newsk->sk_write_queue); rwlock_init(&newsk->sk_dst_lock); rwlock_init(&newsk->sk_callback_lock); newsk->sk_dst_cache = NULL; newsk->sk_wmem_queued = 0; newsk->sk_forward_alloc = 0; newsk->sk_send_head = NULL; newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; newsk->sk_userlocks = sk->sk_userlocks & ~SOCK_BINDPORT_LOCK; sock_reset_flag(newsk, SOCK_DONE); skb_queue_head_init(&newsk->sk_error_queue); filter = newsk->sk_filter; if (filter != NULL) sk_filter_charge(newsk, filter); if (unlikely(xfrm_sk_clone_policy(newsk))) { /* It is still raw copy of parent, so invalidate * destructor and make plain sk_free() */ newsk->sk_destruct = NULL; sk_free(newsk); newsk = NULL; goto out; } newsk->sk_err = 0; newsk->sk_priority = 0; atomic_set(&newsk->sk_refcnt, 2); /* * Increment the counter in the same struct proto as the master * sock (sk_refcnt_debug_inc uses newsk->sk_prot->socks, that * is the same as sk->sk_prot->socks, as this field was copied * with memcpy). * * This _changes_ the previous behaviour, where * tcp_create_openreq_child always was incrementing the * equivalent to tcp_prot->socks (inet_sock_nr), so this have * to be taken into account in all callers. -acme */ sk_refcnt_debug_inc(newsk); newsk->sk_socket = NULL; newsk->sk_sleep = NULL; if (newsk->sk_prot->sockets_allocated) atomic_inc(newsk->sk_prot->sockets_allocated); } out: return newsk; } EXPORT_SYMBOL_GPL(sk_clone); void __init sk_init(void) { if (num_physpages <= 4096) { sysctl_wmem_max = 32767; sysctl_rmem_max = 32767; sysctl_wmem_default = 32767; sysctl_rmem_default = 32767; } else if (num_physpages >= 131072) { sysctl_wmem_max = 131071; sysctl_rmem_max = 131071; } } /* * Simple resource managers for sockets. */ /* * Write buffer destructor automatically called from kfree_skb. */ void sock_wfree(struct sk_buff *skb) { struct sock *sk = skb->sk; /* In case it might be waiting for more memory. */ atomic_sub(skb->truesize, &sk->sk_wmem_alloc); if (!sock_flag(sk, SOCK_USE_WRITE_QUEUE)) sk->sk_write_space(sk); sock_put(sk); } /* * Read buffer destructor automatically called from kfree_skb. */ void sock_rfree(struct sk_buff *skb) { struct sock *sk = skb->sk; atomic_sub(skb->truesize, &sk->sk_rmem_alloc); } int sock_i_uid(struct sock *sk) { int uid; read_lock(&sk->sk_callback_lock); uid = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : 0; read_unlock(&sk->sk_callback_lock); return uid; } unsigned long sock_i_ino(struct sock *sk) { unsigned long ino; read_lock(&sk->sk_callback_lock); ino = sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_ino : 0; read_unlock(&sk->sk_callback_lock); return ino; } /* * Allocate a skb from the socket's send buffer. */ struct sk_buff *sock_wmalloc(struct sock *sk, unsigned long size, int force, gfp_t priority) { if (force || atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { struct sk_buff * skb = alloc_skb(size, priority); if (skb) { skb_set_owner_w(skb, sk); return skb; } } return NULL; } /* * Allocate a skb from the socket's receive buffer. */ struct sk_buff *sock_rmalloc(struct sock *sk, unsigned long size, int force, gfp_t priority) { if (force || atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) { struct sk_buff *skb = alloc_skb(size, priority); if (skb) { skb_set_owner_r(skb, sk); return skb; } } return NULL; } /* * Allocate a memory block from the socket's option memory buffer. */ void *sock_kmalloc(struct sock *sk, int size, gfp_t priority) { if ((unsigned)size <= sysctl_optmem_max && atomic_read(&sk->sk_omem_alloc) + size < sysctl_optmem_max) { void *mem; /* First do the add, to avoid the race if kmalloc * might sleep. */ atomic_add(size, &sk->sk_omem_alloc); mem = kmalloc(size, priority); if (mem) return mem; atomic_sub(size, &sk->sk_omem_alloc); } return NULL; } /* * Free an option memory block. */ void sock_kfree_s(struct sock *sk, void *mem, int size) { kfree(mem); atomic_sub(size, &sk->sk_omem_alloc); } /* It is almost wait_for_tcp_memory minus release_sock/lock_sock. I think, these locks should be removed for datagram sockets. */ static long sock_wait_for_wmem(struct sock * sk, long timeo) { DEFINE_WAIT(wait); clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); for (;;) { if (!timeo) break; if (signal_pending(current)) break; set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE); if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) break; if (sk->sk_shutdown & SEND_SHUTDOWN) break; if (sk->sk_err) break; timeo = schedule_timeout(timeo); } finish_wait(sk->sk_sleep, &wait); return timeo; } /* * Generic send/receive buffer handlers */ static struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len, unsigned long data_len, int noblock, int *errcode) { struct sk_buff *skb; gfp_t gfp_mask; long timeo; int err; gfp_mask = sk->sk_allocation; if (gfp_mask & __GFP_WAIT) gfp_mask |= __GFP_REPEAT; timeo = sock_sndtimeo(sk, noblock); while (1) { err = sock_error(sk); if (err != 0) goto failure; err = -EPIPE; if (sk->sk_shutdown & SEND_SHUTDOWN) goto failure; if (atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf) { skb = alloc_skb(header_len, sk->sk_allocation); if (skb) { int npages; int i; /* No pages, we're done... */ if (!data_len) break; npages = (data_len + (PAGE_SIZE - 1)) >> PAGE_SHIFT; skb->truesize += data_len; skb_shinfo(skb)->nr_frags = npages; for (i = 0; i < npages; i++) { struct page *page; skb_frag_t *frag; page = alloc_pages(sk->sk_allocation, 0); if (!page) { err = -ENOBUFS; skb_shinfo(skb)->nr_frags = i; kfree_skb(skb); goto failure; } frag = &skb_shinfo(skb)->frags[i]; frag->page = page; frag->page_offset = 0; frag->size = (data_len >= PAGE_SIZE ? PAGE_SIZE : data_len); data_len -= PAGE_SIZE; } /* Full success... */ break; } err = -ENOBUFS; goto failure; } set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags); set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); err = -EAGAIN; if (!timeo) goto failure; if (signal_pending(current)) goto interrupted; timeo = sock_wait_for_wmem(sk, timeo); } skb_set_owner_w(skb, sk); return skb; interrupted: err = sock_intr_errno(timeo); failure: *errcode = err; return NULL; } struct sk_buff *sock_alloc_send_skb(struct sock *sk, unsigned long size, int noblock, int *errcode) { return sock_alloc_send_pskb(sk, size, 0, noblock, errcode); } static void __lock_sock(struct sock *sk) { DEFINE_WAIT(wait); for(;;) { prepare_to_wait_exclusive(&sk->sk_lock.wq, &wait, TASK_UNINTERRUPTIBLE); spin_unlock_bh(&sk->sk_lock.slock); schedule(); spin_lock_bh(&sk->sk_lock.slock); if(!sock_owned_by_user(sk)) break; } finish_wait(&sk->sk_lock.wq, &wait); } static void __release_sock(struct sock *sk) { struct sk_buff *skb = sk->sk_backlog.head; do { sk->sk_backlog.head = sk->sk_backlog.tail = NULL; bh_unlock_sock(sk); do { struct sk_buff *next = skb->next; skb->next = NULL; sk->sk_backlog_rcv(sk, skb); /* * We are in process context here with softirqs * disabled, use cond_resched_softirq() to preempt. * This is safe to do because we've taken the backlog * queue private: */ cond_resched_softirq(); skb = next; } while (skb != NULL); bh_lock_sock(sk); } while((skb = sk->sk_backlog.head) != NULL); } /** * sk_wait_data - wait for data to arrive at sk_receive_queue * @sk: sock to wait on * @timeo: for how long * * Now socket state including sk->sk_err is changed only under lock, * hence we may omit checks after joining wait queue. * We check receive queue before schedule() only as optimization; * it is very likely that release_sock() added new data. */ int sk_wait_data(struct sock *sk, long *timeo) { int rc; DEFINE_WAIT(wait); prepare_to_wait(sk->sk_sleep, &wait, TASK_INTERRUPTIBLE); set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); rc = sk_wait_event(sk, timeo, !skb_queue_empty(&sk->sk_receive_queue)); clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags); finish_wait(sk->sk_sleep, &wait); return rc; } EXPORT_SYMBOL(sk_wait_data); /* * Set of default routines for initialising struct proto_ops when * the protocol does not support a particular function. In certain * cases where it makes no sense for a protocol to have a "do nothing" * function, some default processing is provided. */ int sock_no_bind(struct socket *sock, struct sockaddr *saddr, int len) { return -EOPNOTSUPP; } int sock_no_connect(struct socket *sock, struct sockaddr *saddr, int len, int flags) { return -EOPNOTSUPP; } int sock_no_socketpair(struct socket *sock1, struct socket *sock2) { return -EOPNOTSUPP; } int sock_no_accept(struct socket *sock, struct socket *newsock, int flags) { return -EOPNOTSUPP; } int sock_no_getname(struct socket *sock, struct sockaddr *saddr, int *len, int peer) { return -EOPNOTSUPP; } unsigned int sock_no_poll(struct file * file, struct socket *sock, poll_table *pt) { return 0; } int sock_no_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) { return -EOPNOTSUPP; } int sock_no_listen(struct socket *sock, int backlog) { return -EOPNOTSUPP; } int sock_no_shutdown(struct socket *sock, int how) { return -EOPNOTSUPP; } int sock_no_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen) { return -EOPNOTSUPP; } int sock_no_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen) { return -EOPNOTSUPP; } int sock_no_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t len) { return -EOPNOTSUPP; } int sock_no_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t len, int flags) { return -EOPNOTSUPP; } int sock_no_mmap(struct file *file, struct socket *sock, struct vm_area_struct *vma) { /* Mirror missing mmap method error code */ return -ENODEV; } ssize_t sock_no_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) { ssize_t res; struct msghdr msg = {.msg_flags = flags}; struct kvec iov; char *kaddr = kmap(page); iov.iov_base = kaddr + offset; iov.iov_len = size; res = kernel_sendmsg(sock, &msg, &iov, 1, size); kunmap(page); return res; } /* * Default Socket Callbacks */ static void sock_def_wakeup(struct sock *sk) { read_lock(&sk->sk_callback_lock); if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible_all(sk->sk_sleep); read_unlock(&sk->sk_callback_lock); } static void sock_def_error_report(struct sock *sk) { read_lock(&sk->sk_callback_lock); if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible(sk->sk_sleep); sk_wake_async(sk,0,POLL_ERR); read_unlock(&sk->sk_callback_lock); } static void sock_def_readable(struct sock *sk, int len) { read_lock(&sk->sk_callback_lock); if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible(sk->sk_sleep); sk_wake_async(sk,1,POLL_IN); read_unlock(&sk->sk_callback_lock); } static void sock_def_write_space(struct sock *sk) { read_lock(&sk->sk_callback_lock); /* Do not wake up a writer until he can make "significant" * progress. --DaveM */ if((atomic_read(&sk->sk_wmem_alloc) << 1) <= sk->sk_sndbuf) { if (sk->sk_sleep && waitqueue_active(sk->sk_sleep)) wake_up_interruptible(sk->sk_sleep); /* Should agree with poll, otherwise some programs break */ if (sock_writeable(sk)) sk_wake_async(sk, 2, POLL_OUT); } read_unlock(&sk->sk_callback_lock); } static void sock_def_destruct(struct sock *sk) { if (sk->sk_protinfo) kfree(sk->sk_protinfo); } void sk_send_sigurg(struct sock *sk) { if (sk->sk_socket && sk->sk_socket->file) if (send_sigurg(&sk->sk_socket->file->f_owner)) sk_wake_async(sk, 3, POLL_PRI); } void sk_reset_timer(struct sock *sk, struct timer_list* timer, unsigned long expires) { if (!mod_timer(timer, expires)) sock_hold(sk); } EXPORT_SYMBOL(sk_reset_timer); void sk_stop_timer(struct sock *sk, struct timer_list* timer) { if (timer_pending(timer) && del_timer(timer)) __sock_put(sk); } EXPORT_SYMBOL(sk_stop_timer); void sock_init_data(struct socket *sock, struct sock *sk) { skb_queue_head_init(&sk->sk_receive_queue); skb_queue_head_init(&sk->sk_write_queue); skb_queue_head_init(&sk->sk_error_queue); sk->sk_send_head = NULL; init_timer(&sk->sk_timer); sk->sk_allocation = GFP_KERNEL; sk->sk_rcvbuf = sysctl_rmem_default; sk->sk_sndbuf = sysctl_wmem_default; sk->sk_state = TCP_CLOSE; sk->sk_socket = sock; sock_set_flag(sk, SOCK_ZAPPED); if(sock) { sk->sk_type = sock->type; sk->sk_sleep = &sock->wait; sock->sk = sk; } else sk->sk_sleep = NULL; rwlock_init(&sk->sk_dst_lock); rwlock_init(&sk->sk_callback_lock); sk->sk_state_change = sock_def_wakeup; sk->sk_data_ready = sock_def_readable; sk->sk_write_space = sock_def_write_space; sk->sk_error_report = sock_def_error_report; sk->sk_destruct = sock_def_destruct; sk->sk_sndmsg_page = NULL; sk->sk_sndmsg_off = 0; sk->sk_peercred.pid = 0; sk->sk_peercred.uid = -1; sk->sk_peercred.gid = -1; sk->sk_write_pending = 0; sk->sk_rcvlowat = 1; sk->sk_rcvtimeo = MAX_SCHEDULE_TIMEOUT; sk->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT; sk->sk_stamp.tv_sec = -1L; sk->sk_stamp.tv_usec = -1L; atomic_set(&sk->sk_refcnt, 1); } void fastcall lock_sock(struct sock *sk) { might_sleep(); spin_lock_bh(&(sk->sk_lock.slock)); if (sk->sk_lock.owner) __lock_sock(sk); sk->sk_lock.owner = (void *)1; spin_unlock_bh(&(sk->sk_lock.slock)); } EXPORT_SYMBOL(lock_sock); void fastcall release_sock(struct sock *sk) { spin_lock_bh(&(sk->sk_lock.slock)); if (sk->sk_backlog.tail) __release_sock(sk); sk->sk_lock.owner = NULL; if (waitqueue_active(&(sk->sk_lock.wq))) wake_up(&(sk->sk_lock.wq)); spin_unlock_bh(&(sk->sk_lock.slock)); } EXPORT_SYMBOL(release_sock); int sock_get_timestamp(struct sock *sk, struct timeval __user *userstamp) { if (!sock_flag(sk, SOCK_TIMESTAMP)) sock_enable_timestamp(sk); if (sk->sk_stamp.tv_sec == -1) return -ENOENT; if (sk->sk_stamp.tv_sec == 0) do_gettimeofday(&sk->sk_stamp); return copy_to_user(userstamp, &sk->sk_stamp, sizeof(struct timeval)) ? -EFAULT : 0; } EXPORT_SYMBOL(sock_get_timestamp); void sock_enable_timestamp(struct sock *sk) { if (!sock_flag(sk, SOCK_TIMESTAMP)) { sock_set_flag(sk, SOCK_TIMESTAMP); net_enable_timestamp(); } } EXPORT_SYMBOL(sock_enable_timestamp); /* * Get a socket option on an socket. * * FIX: POSIX 1003.1g is very ambiguous here. It states that * asynchronous errors should be reported by getsockopt. We assume * this means if you specify SO_ERROR (otherwise whats the point of it). */ int sock_common_getsockopt(struct socket *sock, int level, int optname, char __user *optval, int __user *optlen) { struct sock *sk = sock->sk; return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_getsockopt); int sock_common_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t size, int flags) { struct sock *sk = sock->sk; int addr_len = 0; int err; err = sk->sk_prot->recvmsg(iocb, sk, msg, size, flags & MSG_DONTWAIT, flags & ~MSG_DONTWAIT, &addr_len); if (err >= 0) msg->msg_namelen = addr_len; return err; } EXPORT_SYMBOL(sock_common_recvmsg); /* * Set socket options on an inet socket. */ int sock_common_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen) { struct sock *sk = sock->sk; return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_setsockopt); void sk_common_release(struct sock *sk) { if (sk->sk_prot->destroy) sk->sk_prot->destroy(sk); /* * Observation: when sock_common_release is called, processes have * no access to socket. But net still has. * Step one, detach it from networking: * * A. Remove from hash tables. */ sk->sk_prot->unhash(sk); /* * In this point socket cannot receive new packets, but it is possible * that some packets are in flight because some CPU runs receiver and * did hash table lookup before we unhashed socket. They will achieve * receive queue and will be purged by socket destructor. * * Also we still have packets pending on receive queue and probably, * our own packets waiting in device queues. sock_destroy will drain * receive queue, but transmitted packets will delay socket destruction * until the last reference will be released. */ sock_orphan(sk); xfrm_sk_free_policy(sk); sk_refcnt_debug_release(sk); sock_put(sk); } EXPORT_SYMBOL(sk_common_release); static DEFINE_RWLOCK(proto_list_lock); static LIST_HEAD(proto_list); int proto_register(struct proto *prot, int alloc_slab) { char *request_sock_slab_name = NULL; char *timewait_sock_slab_name; int rc = -ENOBUFS; if (alloc_slab) { prot->slab = kmem_cache_create(prot->name, prot->obj_size, 0, SLAB_HWCACHE_ALIGN, NULL, NULL); if (prot->slab == NULL) { printk(KERN_CRIT "%s: Can't create sock SLAB cache!\n", prot->name); goto out; } if (prot->rsk_prot != NULL) { static const char mask[] = "request_sock_%s"; request_sock_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL); if (request_sock_slab_name == NULL) goto out_free_sock_slab; sprintf(request_sock_slab_name, mask, prot->name); prot->rsk_prot->slab = kmem_cache_create(request_sock_slab_name, prot->rsk_prot->obj_size, 0, SLAB_HWCACHE_ALIGN, NULL, NULL); if (prot->rsk_prot->slab == NULL) { printk(KERN_CRIT "%s: Can't create request sock SLAB cache!\n", prot->name); goto out_free_request_sock_slab_name; } } if (prot->twsk_obj_size) { static const char mask[] = "tw_sock_%s"; timewait_sock_slab_name = kmalloc(strlen(prot->name) + sizeof(mask) - 1, GFP_KERNEL); if (timewait_sock_slab_name == NULL) goto out_free_request_sock_slab; sprintf(timewait_sock_slab_name, mask, prot->name); prot->twsk_slab = kmem_cache_create(timewait_sock_slab_name, prot->twsk_obj_size, 0, SLAB_HWCACHE_ALIGN, NULL, NULL); if (prot->twsk_slab == NULL) goto out_free_timewait_sock_slab_name; } } write_lock(&proto_list_lock); list_add(&prot->node, &proto_list); write_unlock(&proto_list_lock); rc = 0; out: return rc; out_free_timewait_sock_slab_name: kfree(timewait_sock_slab_name); out_free_request_sock_slab: if (prot->rsk_prot && prot->rsk_prot->slab) { kmem_cache_destroy(prot->rsk_prot->slab); prot->rsk_prot->slab = NULL; } out_free_request_sock_slab_name: kfree(request_sock_slab_name); out_free_sock_slab: kmem_cache_destroy(prot->slab); prot->slab = NULL; goto out; } EXPORT_SYMBOL(proto_register); void proto_unregister(struct proto *prot) { write_lock(&proto_list_lock); list_del(&prot->node); write_unlock(&proto_list_lock); if (prot->slab != NULL) { kmem_cache_destroy(prot->slab); prot->slab = NULL; } if (prot->rsk_prot != NULL && prot->rsk_prot->slab != NULL) { const char *name = kmem_cache_name(prot->rsk_prot->slab); kmem_cache_destroy(prot->rsk_prot->slab); kfree(name); prot->rsk_prot->slab = NULL; } if (prot->twsk_slab != NULL) { const char *name = kmem_cache_name(prot->twsk_slab); kmem_cache_destroy(prot->twsk_slab); kfree(name); prot->twsk_slab = NULL; } } EXPORT_SYMBOL(proto_unregister); #ifdef CONFIG_PROC_FS static inline struct proto *__proto_head(void) { return list_entry(proto_list.next, struct proto, node); } static inline struct proto *proto_head(void) { return list_empty(&proto_list) ? NULL : __proto_head(); } static inline struct proto *proto_next(struct proto *proto) { return proto->node.next == &proto_list ? NULL : list_entry(proto->node.next, struct proto, node); } static inline struct proto *proto_get_idx(loff_t pos) { struct proto *proto; loff_t i = 0; list_for_each_entry(proto, &proto_list, node) if (i++ == pos) goto out; proto = NULL; out: return proto; } static void *proto_seq_start(struct seq_file *seq, loff_t *pos) { read_lock(&proto_list_lock); return *pos ? proto_get_idx(*pos - 1) : SEQ_START_TOKEN; } static void *proto_seq_next(struct seq_file *seq, void *v, loff_t *pos) { ++*pos; return v == SEQ_START_TOKEN ? proto_head() : proto_next(v); } static void proto_seq_stop(struct seq_file *seq, void *v) { read_unlock(&proto_list_lock); } static char proto_method_implemented(const void *method) { return method == NULL ? 'n' : 'y'; } static void proto_seq_printf(struct seq_file *seq, struct proto *proto) { seq_printf(seq, "%-9s %4u %6d %6d %-3s %6u %-3s %-10s " "%2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c %2c\n", proto->name, proto->obj_size, proto->sockets_allocated != NULL ? atomic_read(proto->sockets_allocated) : -1, proto->memory_allocated != NULL ? atomic_read(proto->memory_allocated) : -1, proto->memory_pressure != NULL ? *proto->memory_pressure ? "yes" : "no" : "NI", proto->max_header, proto->slab == NULL ? "no" : "yes", module_name(proto->owner), proto_method_implemented(proto->close), proto_method_implemented(proto->connect), proto_method_implemented(proto->disconnect), proto_method_implemented(proto->accept), proto_method_implemented(proto->ioctl), proto_method_implemented(proto->init), proto_method_implemented(proto->destroy), proto_method_implemented(proto->shutdown), proto_method_implemented(proto->setsockopt), proto_method_implemented(proto->getsockopt), proto_method_implemented(proto->sendmsg), proto_method_implemented(proto->recvmsg), proto_method_implemented(proto->sendpage), proto_method_implemented(proto->bind), proto_method_implemented(proto->backlog_rcv), proto_method_implemented(proto->hash), proto_method_implemented(proto->unhash), proto_method_implemented(proto->get_port), proto_method_implemented(proto->enter_memory_pressure)); } static int proto_seq_show(struct seq_file *seq, void *v) { if (v == SEQ_START_TOKEN) seq_printf(seq, "%-9s %-4s %-8s %-6s %-5s %-7s %-4s %-10s %s", "protocol", "size", "sockets", "memory", "press", "maxhdr", "slab", "module", "cl co di ac io in de sh ss gs se re sp bi br ha uh gp em\n"); else proto_seq_printf(seq, v); return 0; } static struct seq_operations proto_seq_ops = { .start = proto_seq_start, .next = proto_seq_next, .stop = proto_seq_stop, .show = proto_seq_show, }; static int proto_seq_open(struct inode *inode, struct file *file) { return seq_open(file, &proto_seq_ops); } static struct file_operations proto_seq_fops = { .owner = THIS_MODULE, .open = proto_seq_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release, }; static int __init proto_init(void) { /* register /proc/net/protocols */ return proc_net_fops_create("protocols", S_IRUGO, &proto_seq_fops) == NULL ? -ENOBUFS : 0; } subsys_initcall(proto_init); #endif /* PROC_FS */ EXPORT_SYMBOL(sk_alloc); EXPORT_SYMBOL(sk_free); EXPORT_SYMBOL(sk_send_sigurg); EXPORT_SYMBOL(sock_alloc_send_skb); EXPORT_SYMBOL(sock_init_data); EXPORT_SYMBOL(sock_kfree_s); EXPORT_SYMBOL(sock_kmalloc); EXPORT_SYMBOL(sock_no_accept); EXPORT_SYMBOL(sock_no_bind); EXPORT_SYMBOL(sock_no_connect); EXPORT_SYMBOL(sock_no_getname); EXPORT_SYMBOL(sock_no_getsockopt); EXPORT_SYMBOL(sock_no_ioctl); EXPORT_SYMBOL(sock_no_listen); EXPORT_SYMBOL(sock_no_mmap); EXPORT_SYMBOL(sock_no_poll); EXPORT_SYMBOL(sock_no_recvmsg); EXPORT_SYMBOL(sock_no_sendmsg); EXPORT_SYMBOL(sock_no_sendpage); EXPORT_SYMBOL(sock_no_setsockopt); EXPORT_SYMBOL(sock_no_shutdown); EXPORT_SYMBOL(sock_no_socketpair); EXPORT_SYMBOL(sock_rfree); EXPORT_SYMBOL(sock_setsockopt); EXPORT_SYMBOL(sock_wfree); EXPORT_SYMBOL(sock_wmalloc); EXPORT_SYMBOL(sock_i_uid); EXPORT_SYMBOL(sock_i_ino); EXPORT_SYMBOL(sysctl_optmem_max); #ifdef CONFIG_SYSCTL EXPORT_SYMBOL(sysctl_rmem_max); EXPORT_SYMBOL(sysctl_wmem_max); #endif