diff options
| -rw-r--r-- | include/net/ipcomp.h | 6 | ||||
| -rw-r--r-- | net/ipv4/Kconfig | 4 | ||||
| -rw-r--r-- | net/ipv4/ipcomp.c | 315 | ||||
| -rw-r--r-- | net/ipv6/Kconfig | 4 | ||||
| -rw-r--r-- | net/ipv6/ipcomp6.c | 298 | ||||
| -rw-r--r-- | net/xfrm/Kconfig | 6 | ||||
| -rw-r--r-- | net/xfrm/Makefile | 1 | ||||
| -rw-r--r-- | net/xfrm/xfrm_ipcomp.c | 349 |
8 files changed, 377 insertions, 606 deletions
diff --git a/include/net/ipcomp.h b/include/net/ipcomp.h index 330b74e813a9..2a1092abaa07 100644 --- a/include/net/ipcomp.h +++ b/include/net/ipcomp.h @@ -14,6 +14,12 @@ struct ipcomp_data { struct ip_comp_hdr; struct sk_buff; +struct xfrm_state; + +int ipcomp_input(struct xfrm_state *x, struct sk_buff *skb); +int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb); +void ipcomp_destroy(struct xfrm_state *x); +int ipcomp_init_state(struct xfrm_state *x); static inline struct ip_comp_hdr *ip_comp_hdr(const struct sk_buff *skb) { diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig index 4670683b4688..591ea23639ca 100644 --- a/net/ipv4/Kconfig +++ b/net/ipv4/Kconfig @@ -356,10 +356,8 @@ config INET_ESP config INET_IPCOMP tristate "IP: IPComp transformation" - select XFRM select INET_XFRM_TUNNEL - select CRYPTO - select CRYPTO_DEFLATE + select XFRM_IPCOMP ---help--- Support for IP Payload Compression Protocol (IPComp) (RFC3173), typically needed for IPsec. diff --git a/net/ipv4/ipcomp.c b/net/ipv4/ipcomp.c index a75807b971b3..a42b64d040c4 100644 --- a/net/ipv4/ipcomp.c +++ b/net/ipv4/ipcomp.c @@ -14,153 +14,14 @@ * - Adaptive compression. */ #include <linux/module.h> -#include <linux/crypto.h> #include <linux/err.h> -#include <linux/pfkeyv2.h> -#include <linux/percpu.h> -#include <linux/smp.h> -#include <linux/list.h> -#include <linux/vmalloc.h> #include <linux/rtnetlink.h> -#include <linux/mutex.h> #include <net/ip.h> #include <net/xfrm.h> #include <net/icmp.h> #include <net/ipcomp.h> #include <net/protocol.h> - -struct ipcomp_tfms { - struct list_head list; - struct crypto_comp **tfms; - int users; -}; - -static DEFINE_MUTEX(ipcomp_resource_mutex); -static void **ipcomp_scratches; -static int ipcomp_scratch_users; -static LIST_HEAD(ipcomp_tfms_list); - -static int ipcomp_decompress(struct xfrm_state *x, struct sk_buff *skb) -{ - struct ipcomp_data *ipcd = x->data; - const int plen = skb->len; - int dlen = IPCOMP_SCRATCH_SIZE; - const u8 *start = skb->data; - const int cpu = get_cpu(); - u8 *scratch = *per_cpu_ptr(ipcomp_scratches, cpu); - struct crypto_comp *tfm = *per_cpu_ptr(ipcd->tfms, cpu); - int err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen); - - if (err) - goto out; - - if (dlen < (plen + sizeof(struct ip_comp_hdr))) { - err = -EINVAL; - goto out; - } - - err = pskb_expand_head(skb, 0, dlen - plen, GFP_ATOMIC); - if (err) - goto out; - - skb->truesize += dlen - plen; - __skb_put(skb, dlen - plen); - skb_copy_to_linear_data(skb, scratch, dlen); -out: - put_cpu(); - return err; -} - -static int ipcomp_input(struct xfrm_state *x, struct sk_buff *skb) -{ - int nexthdr; - int err = -ENOMEM; - struct ip_comp_hdr *ipch; - - if (skb_linearize_cow(skb)) - goto out; - - skb->ip_summed = CHECKSUM_NONE; - - /* Remove ipcomp header and decompress original payload */ - ipch = (void *)skb->data; - nexthdr = ipch->nexthdr; - - skb->transport_header = skb->network_header + sizeof(*ipch); - __skb_pull(skb, sizeof(*ipch)); - err = ipcomp_decompress(x, skb); - if (err) - goto out; - - err = nexthdr; - -out: - return err; -} - -static int ipcomp_compress(struct xfrm_state *x, struct sk_buff *skb) -{ - struct ipcomp_data *ipcd = x->data; - const int plen = skb->len; - int dlen = IPCOMP_SCRATCH_SIZE; - u8 *start = skb->data; - const int cpu = get_cpu(); - u8 *scratch = *per_cpu_ptr(ipcomp_scratches, cpu); - struct crypto_comp *tfm = *per_cpu_ptr(ipcd->tfms, cpu); - int err; - - local_bh_disable(); - err = crypto_comp_compress(tfm, start, plen, scratch, &dlen); - local_bh_enable(); - if (err) - goto out; - - if ((dlen + sizeof(struct ip_comp_hdr)) >= plen) { - err = -EMSGSIZE; - goto out; - } - - memcpy(start + sizeof(struct ip_comp_hdr), scratch, dlen); - put_cpu(); - - pskb_trim(skb, dlen + sizeof(struct ip_comp_hdr)); - return 0; - -out: - put_cpu(); - return err; -} - -static int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb) -{ - int err; - struct ip_comp_hdr *ipch; - struct ipcomp_data *ipcd = x->data; - - if (skb->len < ipcd->threshold) { - /* Don't bother compressing */ - goto out_ok; - } - - if (skb_linearize_cow(skb)) - goto out_ok; - - err = ipcomp_compress(x, skb); - - if (err) { - goto out_ok; - } - - /* Install ipcomp header, convert into ipcomp datagram. */ - ipch = ip_comp_hdr(skb); - ipch->nexthdr = *skb_mac_header(skb); - ipch->flags = 0; - ipch->cpi = htons((u16 )ntohl(x->id.spi)); - *skb_mac_header(skb) = IPPROTO_COMP; -out_ok: - skb_push(skb, -skb_network_offset(skb)); - return 0; -} +#include <net/sock.h> static void ipcomp4_err(struct sk_buff *skb, u32 info) { @@ -241,156 +102,12 @@ out: return err; } -static void ipcomp_free_scratches(void) -{ - int i; - void **scratches; - - if (--ipcomp_scratch_users) - return; - - scratches = ipcomp_scratches; - if (!scratches) - return; - - for_each_possible_cpu(i) - vfree(*per_cpu_ptr(scratches, i)); - - free_percpu(scratches); -} - -static void **ipcomp_alloc_scratches(void) -{ - int i; - void **scratches; - - if (ipcomp_scratch_users++) - return ipcomp_scratches; - - scratches = alloc_percpu(void *); - if (!scratches) - return NULL; - - ipcomp_scratches = scratches; - - for_each_possible_cpu(i) { - void *scratch = vmalloc(IPCOMP_SCRATCH_SIZE); - if (!scratch) - return NULL; - *per_cpu_ptr(scratches, i) = scratch; - } - - return scratches; -} - -static void ipcomp_free_tfms(struct crypto_comp **tfms) -{ - struct ipcomp_tfms *pos; - int cpu; - - list_for_each_entry(pos, &ipcomp_tfms_list, list) { - if (pos->tfms == tfms) - break; - } - - BUG_TRAP(pos); - - if (--pos->users) - return; - - list_del(&pos->list); - kfree(pos); - - if (!tfms) - return; - - for_each_possible_cpu(cpu) { - struct crypto_comp *tfm = *per_cpu_ptr(tfms, cpu); - crypto_free_comp(tfm); - } - free_percpu(tfms); -} - -static struct crypto_comp **ipcomp_alloc_tfms(const char *alg_name) -{ - struct ipcomp_tfms *pos; - struct crypto_comp **tfms; - int cpu; - - /* This can be any valid CPU ID so we don't need locking. */ - cpu = raw_smp_processor_id(); - - list_for_each_entry(pos, &ipcomp_tfms_list, list) { - struct crypto_comp *tfm; - - tfms = pos->tfms; - tfm = *per_cpu_ptr(tfms, cpu); - - if (!strcmp(crypto_comp_name(tfm), alg_name)) { - pos->users++; - return tfms; - } - } - - pos = kmalloc(sizeof(*pos), GFP_KERNEL); - if (!pos) - return NULL; - - pos->users = 1; - INIT_LIST_HEAD(&pos->list); - list_add(&pos->list, &ipcomp_tfms_list); - - pos->tfms = tfms = alloc_percpu(struct crypto_comp *); - if (!tfms) - goto error; - - for_each_possible_cpu(cpu) { - struct crypto_comp *tfm = crypto_alloc_comp(alg_name, 0, - CRYPTO_ALG_ASYNC); - if (IS_ERR(tfm)) - goto error; - *per_cpu_ptr(tfms, cpu) = tfm; - } - - return tfms; - -error: - ipcomp_free_tfms(tfms); - return NULL; -} - -static void ipcomp_free_data(struct ipcomp_data *ipcd) -{ - if (ipcd->tfms) - ipcomp_free_tfms(ipcd->tfms); - ipcomp_free_scratches(); -} - -static void ipcomp_destroy(struct xfrm_state *x) -{ - struct ipcomp_data *ipcd = x->data; - if (!ipcd) - return; - xfrm_state_delete_tunnel(x); - mutex_lock(&ipcomp_resource_mutex); - ipcomp_free_data(ipcd); - mutex_unlock(&ipcomp_resource_mutex); - kfree(ipcd); -} - -static int ipcomp_init_state(struct xfrm_state *x) +static int ipcomp4_init_state(struct xfrm_state *x) { int err; struct ipcomp_data *ipcd; struct xfrm_algo_desc *calg_desc; - err = -EINVAL; - if (!x->calg) - goto out; - - if (x->encap) - goto out; - x->props.header_len = 0; switch (x->props.mode) { case XFRM_MODE_TRANSPORT: @@ -402,40 +119,22 @@ static int ipcomp_init_state(struct xfrm_state *x) goto out; } - err = -ENOMEM; - ipcd = kzalloc(sizeof(*ipcd), GFP_KERNEL); - if (!ipcd) + err = ipcomp_init_state(x); + if (err) goto out; - mutex_lock(&ipcomp_resource_mutex); - if (!ipcomp_alloc_scratches()) - goto error; - - ipcd->tfms = ipcomp_alloc_tfms(x->calg->alg_name); - if (!ipcd->tfms) - goto error; - mutex_unlock(&ipcomp_resource_mutex); - if (x->props.mode == XFRM_MODE_TUNNEL) { err = ipcomp_tunnel_attach(x); if (err) goto error_tunnel; } - calg_desc = xfrm_calg_get_byname(x->calg->alg_name, 0); - BUG_ON(!calg_desc); - ipcd->threshold = calg_desc->uinfo.comp.threshold; - x->data = ipcd; err = 0; out: return err; error_tunnel: - mutex_lock(&ipcomp_resource_mutex); -error: - ipcomp_free_data(ipcd); - mutex_unlock(&ipcomp_resource_mutex); - kfree(ipcd); + ipcomp_destroy(x); goto out; } @@ -443,7 +142,7 @@ static const struct xfrm_type ipcomp_type = { .description = "IPCOMP4", .owner = THIS_MODULE, .proto = IPPROTO_COMP, - .init_state = ipcomp_init_state, + .init_state = ipcomp4_init_state, .destructor = ipcomp_destroy, .input = ipcomp_input, .output = ipcomp_output @@ -481,7 +180,7 @@ module_init(ipcomp4_init); module_exit(ipcomp4_fini); MODULE_LICENSE("GPL"); -MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) - RFC3173"); +MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp/IPv4) - RFC3173"); MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>"); MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_COMP); diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig index 42814a2ec9d7..ec992159b5f8 100644 --- a/net/ipv6/Kconfig +++ b/net/ipv6/Kconfig @@ -96,10 +96,8 @@ config INET6_ESP config INET6_IPCOMP tristate "IPv6: IPComp transformation" - select XFRM select INET6_XFRM_TUNNEL - select CRYPTO - select CRYPTO_DEFLATE + select XFRM_IPCOMP ---help--- Support for IP Payload Compression Protocol (IPComp) (RFC3173), typically needed for IPsec. diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c index ee6de425ce6b..0cfcea42153a 100644 --- a/net/ipv6/ipcomp6.c +++ b/net/ipv6/ipcomp6.c @@ -50,125 +50,6 @@ #include <linux/icmpv6.h> #include <linux/mutex.h> -struct ipcomp6_tfms { - struct list_head list; - struct crypto_comp **tfms; - int users; -}; - -static DEFINE_MUTEX(ipcomp6_resource_mutex); -static void **ipcomp6_scratches; -static int ipcomp6_scratch_users; -static LIST_HEAD(ipcomp6_tfms_list); - -static int ipcomp6_input(struct xfrm_state *x, struct sk_buff *skb) -{ - int nexthdr; - int err = -ENOMEM; - struct ip_comp_hdr *ipch; - int plen, dlen; - struct ipcomp_data *ipcd = x->data; - u8 *start, *scratch; - struct crypto_comp *tfm; - int cpu; - - if (skb_linearize_cow(skb)) - goto out; - - skb->ip_summed = CHECKSUM_NONE; - - /* Remove ipcomp header and decompress original payload */ - ipch = (void *)skb->data; - nexthdr = ipch->nexthdr; - - skb->transport_header = skb->network_header + sizeof(*ipch); - __skb_pull(skb, sizeof(*ipch)); - - /* decompression */ - plen = skb->len; - dlen = IPCOMP_SCRATCH_SIZE; - start = skb->data; - - cpu = get_cpu(); - scratch = *per_cpu_ptr(ipcomp6_scratches, cpu); - tfm = *per_cpu_ptr(ipcd->tfms, cpu); - - err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen); - if (err) - goto out_put_cpu; - - if (dlen < (plen + sizeof(*ipch))) { - err = -EINVAL; - goto out_put_cpu; - } - - err = pskb_expand_head(skb, 0, dlen - plen, GFP_ATOMIC); - if (err) { - goto out_put_cpu; - } - - skb->truesize += dlen - plen; - __skb_put(skb, dlen - plen); - skb_copy_to_linear_data(skb, scratch, dlen); - err = nexthdr; - -out_put_cpu: - put_cpu(); -out: - return err; -} - -static int ipcomp6_output(struct xfrm_state *x, struct sk_buff *skb) -{ - int err; - struct ip_comp_hdr *ipch; - struct ipcomp_data *ipcd = x->data; - int plen, dlen; - u8 *start, *scratch; - struct crypto_comp *tfm; - int cpu; - - /* check whether datagram len is larger than threshold */ - if (skb->len < ipcd->threshold) { - goto out_ok; - } - - if (skb_linearize_cow(skb)) - goto out_ok; - - /* compression */ - plen = skb->len; - dlen = IPCOMP_SCRATCH_SIZE; - start = skb->data; - - cpu = get_cpu(); - scratch = *per_cpu_ptr(ipcomp6_scratches, cpu); - tfm = *per_cpu_ptr(ipcd->tfms, cpu); - - local_bh_disable(); - err = crypto_comp_compress(tfm, start, plen, scratch, &dlen); - local_bh_enable(); - if (err || (dlen + sizeof(*ipch)) >= plen) { - put_cpu(); - goto out_ok; - } - memcpy(start + sizeof(struct ip_comp_hdr), scratch, dlen); - put_cpu(); - pskb_trim(skb, dlen + sizeof(struct ip_comp_hdr)); - - /* insert ipcomp header and replace datagram */ - ipch = ip_comp_hdr(skb); - ipch->nexthdr = *skb_mac_header(skb); - ipch->flags = 0; - ipch->cpi = htons((u16 )ntohl(x->id.spi)); - *skb_mac_header(skb) = IPPROTO_COMP; - -out_ok: - skb_push(skb, -skb_network_offset(skb)); - - return 0; -} - static void ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, int type, int code, int offset, __be32 info) { @@ -251,161 +132,12 @@ out: return err; } -static void ipcomp6_free_scratches(void) -{ - int i; - void **scratches; - - if (--ipcomp6_scratch_users) - return; - - scratches = ipcomp6_scratches; - if (!scratches) - return; - - for_each_possible_cpu(i) { - void *scratch = *per_cpu_ptr(scratches, i); - - vfree(scratch); - } - - free_percpu(scratches); -} - -static void **ipcomp6_alloc_scratches(void) -{ - int i; - void **scratches; - - if (ipcomp6_scratch_users++) - return ipcomp6_scratches; - - scratches = alloc_percpu(void *); - if (!scratches) - return NULL; - - ipcomp6_scratches = scratches; - - for_each_possible_cpu(i) { - void *scratch = vmalloc(IPCOMP_SCRATCH_SIZE); - if (!scratch) - return NULL; - *per_cpu_ptr(scratches, i) = scratch; - } - - return scratches; -} - -static void ipcomp6_free_tfms(struct crypto_comp **tfms) -{ - struct ipcomp6_tfms *pos; - int cpu; - - list_for_each_entry(pos, &ipcomp6_tfms_list, list) { - if (pos->tfms == tfms) - break; - } - - BUG_TRAP(pos); - - if (--pos->users) - return; - - list_del(&pos->list); - kfree(pos); - - if (!tfms) - return; - - for_each_possible_cpu(cpu) { - struct crypto_comp *tfm = *per_cpu_ptr(tfms, cpu); - crypto_free_comp(tfm); - } - free_percpu(tfms); -} - -static struct crypto_comp **ipcomp6_alloc_tfms(const char *alg_name) -{ - struct ipcomp6_tfms *pos; - struct crypto_comp **tfms; - int cpu; - - /* This can be any valid CPU ID so we don't need locking. */ - cpu = raw_smp_processor_id(); - - list_for_each_entry(pos, &ipcomp6_tfms_list, list) { - struct crypto_comp *tfm; - - tfms = pos->tfms; - tfm = *per_cpu_ptr(tfms, cpu); - - if (!strcmp(crypto_comp_name(tfm), alg_name)) { - pos->users++; - return tfms; - } - } - - pos = kmalloc(sizeof(*pos), GFP_KERNEL); - if (!pos) - return NULL; - - pos->users = 1; - INIT_LIST_HEAD(&pos->list); - list_add(&pos->list, &ipcomp6_tfms_list); - - pos->tfms = tfms = alloc_percpu(struct crypto_comp *); - if (!tfms) - goto error; - - for_each_possible_cpu(cpu) { - struct crypto_comp *tfm = crypto_alloc_comp(alg_name, 0, - CRYPTO_ALG_ASYNC); - if (IS_ERR(tfm)) - goto error; - *per_cpu_ptr(tfms, cpu) = tfm; - } - - return tfms; - -error: - ipcomp6_free_tfms(tfms); - return NULL; -} - -static void ipcomp6_free_data(struct ipcomp_data *ipcd) -{ - if (ipcd->tfms) - ipcomp6_free_tfms(ipcd->tfms); - ipcomp6_free_scratches(); -} - -static void ipcomp6_destroy(struct xfrm_state *x) -{ - struct ipcomp_data *ipcd = x->data; - if (!ipcd) - return; - xfrm_state_delete_tunnel(x); - mutex_lock(&ipcomp6_resource_mutex); - ipcomp6_free_data(ipcd); - mutex_unlock(&ipcomp6_resource_mutex); - kfree(ipcd); - - xfrm6_tunnel_free_spi((xfrm_address_t *)&x->props.saddr); -} - static int ipcomp6_init_state(struct xfrm_state *x) { int err; struct ipcomp_data *ipcd; struct xfrm_algo_desc *calg_desc; - err = -EINVAL; - if (!x->calg) - goto out; - - if (x->encap) - goto out; - x->props.header_len = 0; switch (x->props.mode) { case XFRM_MODE_TRANSPORT: @@ -417,39 +149,21 @@ static int ipcomp6_init_state(struct xfrm_state *x) goto out; } - err = -ENOMEM; - ipcd = kzalloc(sizeof(*ipcd), GFP_KERNEL); - if (!ipcd) + err = ipcomp_init_state(x); + if (err) goto out; - mutex_lock(&ipcomp6_resource_mutex); - if (!ipcomp6_alloc_scratches()) - goto error; - - ipcd->tfms = ipcomp6_alloc_tfms(x->calg->alg_name); - if (!ipcd->tfms) - goto error; - mutex_unlock(&ipcomp6_resource_mutex); - if (x->props.mode == XFRM_MODE_TUNNEL) { err = ipcomp6_tunnel_attach(x); if (err) goto error_tunnel; } - calg_desc = xfrm_calg_get_byname(x->calg->alg_name, 0); - BUG_ON(!calg_desc); - ipcd->threshold = calg_desc->uinfo.comp.threshold; - x->data = ipcd; err = 0; out: return err; error_tunnel: - mutex_lock(&ipcomp6_resource_mutex); -error: - ipcomp6_free_data(ipcd); - mutex_unlock(&ipcomp6_resource_mutex); - kfree(ipcd); + ipcomp_destroy(x); goto out; } @@ -460,9 +174,9 @@ static const struct xfrm_type ipcomp6_type = .owner = THIS_MODULE, .proto = IPPROTO_COMP, .init_state = ipcomp6_init_state, - .destructor = ipcomp6_destroy, - .input = ipcomp6_input, - .output = ipcomp6_output, + .destructor = ipcomp_destroy, + .input = ipcomp_input, + .output = ipcomp_output, .hdr_offset = xfrm6_find_1stfragopt, }; diff --git a/net/xfrm/Kconfig b/net/xfrm/Kconfig index 9201ef8ad90e..6d081674515f 100644 --- a/net/xfrm/Kconfig +++ b/net/xfrm/Kconfig @@ -46,6 +46,12 @@ config XFRM_STATISTICS If unsure, say N. +config XFRM_IPCOMP + tristate + select XFRM + select CRYPTO + select CRYPTO_DEFLATE + config NET_KEY tristate "PF_KEY sockets" select XFRM diff --git a/net/xfrm/Makefile b/net/xfrm/Makefile index 332cfb0ff566..0f439a72ccab 100644 --- a/net/xfrm/Makefile +++ b/net/xfrm/Makefile @@ -6,4 +6,5 @@ obj-$(CONFIG_XFRM) := xfrm_policy.o xfrm_state.o xfrm_hash.o \ xfrm_input.o xfrm_output.o xfrm_algo.o obj-$(CONFIG_XFRM_STATISTICS) += xfrm_proc.o obj-$(CONFIG_XFRM_USER) += xfrm_user.o +obj-$(CONFIG_XFRM_IPCOMP) += xfrm_ipcomp.o diff --git a/net/xfrm/xfrm_ipcomp.c b/net/xfrm/xfrm_ipcomp.c new file mode 100644 index 000000000000..b51e804fbbad --- /dev/null +++ b/net/xfrm/xfrm_ipcomp.c @@ -0,0 +1,349 @@ +/* + * IP Payload Compression Protocol (IPComp) - RFC3173. + * + * Copyright (c) 2003 James Morris <jmorris@intercode.com.au> + * Copyright (c) 2003-2008 Herbert Xu <herbert@gondor.apana.org.au> + * + * 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. + * + * Todo: + * - Tunable compression parameters. + * - Compression stats. + * - Adaptive compression. + */ + +#include <linux/crypto.h> +#include <linux/err.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/percpu.h> +#include <linux/rtnetlink.h> +#include <linux/smp.h> +#include <linux/vmalloc.h> +#include <net/ip.h> +#include <net/ipcomp.h> +#include <net/xfrm.h> + +struct ipcomp_tfms { + struct list_head list; + struct crypto_comp **tfms; + int users; +}; + +static DEFINE_MUTEX(ipcomp_resource_mutex); +static void **ipcomp_scratches; +static int ipcomp_scratch_users; +static LIST_HEAD(ipcomp_tfms_list); + +static int ipcomp_decompress(struct xfrm_state *x, struct sk_buff *skb) +{ + struct ipcomp_data *ipcd = x->data; + const int plen = skb->len; + int dlen = IPCOMP_SCRATCH_SIZE; + const u8 *start = skb->data; + const int cpu = get_cpu(); + u8 *scratch = *per_cpu_ptr(ipcomp_scratches, cpu); + struct crypto_comp *tfm = *per_cpu_ptr(ipcd->tfms, cpu); + int err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen); + + if (err) + goto out; + + if (dlen < (plen + sizeof(struct ip_comp_hdr))) { + err = -EINVAL; + goto out; + } + + err = pskb_expand_head(skb, 0, dlen - plen, GFP_ATOMIC); + if (err) + goto out; + + skb->truesize += dlen - plen; + __skb_put(skb, dlen - plen); + skb_copy_to_linear_data(skb, scratch, dlen); +out: + put_cpu(); + return err; +} + +int ipcomp_input(struct xfrm_state *x, struct sk_buff *skb) +{ + int nexthdr; + int err = -ENOMEM; + struct ip_comp_hdr *ipch; + + if (skb_linearize_cow(skb)) + goto out; + + skb->ip_summed = CHECKSUM_NONE; + + /* Remove ipcomp header and decompress original payload */ + ipch = (void *)skb->data; + nexthdr = ipch->nexthdr; + + skb->transport_header = skb->network_header + sizeof(*ipch); + __skb_pull(skb, sizeof(*ipch)); + err = ipcomp_decompress(x, skb); + if (err) + goto out; + + err = nexthdr; + +out: + return err; +} +EXPORT_SYMBOL_GPL(ipcomp_input); + +static int ipcomp_compress(struct xfrm_state *x, struct sk_buff *skb) +{ + struct ipcomp_data *ipcd = x->data; + const int plen = skb->len; + int dlen = IPCOMP_SCRATCH_SIZE; + u8 *start = skb->data; + const int cpu = get_cpu(); + u8 *scratch = *per_cpu_ptr(ipcomp_scratches, cpu); + struct crypto_comp *tfm = *per_cpu_ptr(ipcd->tfms, cpu); + int err; + + local_bh_disable(); + err = crypto_comp_compress(tfm, start, plen, scratch, &dlen); + local_bh_enable(); + if (err) + goto out; + + if ((dlen + sizeof(struct ip_comp_hdr)) >= plen) { + err = -EMSGSIZE; + goto out; + } + + memcpy(start + sizeof(struct ip_comp_hdr), scratch, dlen); + put_cpu(); + + pskb_trim(skb, dlen + sizeof(struct ip_comp_hdr)); + return 0; + +out: + put_cpu(); + return err; +} + +int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb) +{ + int err; + struct ip_comp_hdr *ipch; + struct ipcomp_data *ipcd = x->data; + + if (skb->len < ipcd->threshold) { + /* Don't bother compressing */ + goto out_ok; + } + + if (skb_linearize_cow(skb)) + goto out_ok; + + err = ipcomp_compress(x, skb); + + if (err) { + goto out_ok; + } + + /* Install ipcomp header, convert into ipcomp datagram. */ + ipch = ip_comp_hdr(skb); + ipch->nexthdr = *skb_mac_header(skb); + ipch->flags = 0; + ipch->cpi = htons((u16 )ntohl(x->id.spi)); + *skb_mac_header(skb) = IPPROTO_COMP; +out_ok: + skb_push(skb, -skb_network_offset(skb)); + return 0; +} +EXPORT_SYMBOL_GPL(ipcomp_output); + +static void ipcomp_free_scratches(void) +{ + int i; + void **scratches; + + if (--ipcomp_scratch_users) + return; + + scratches = ipcomp_scratches; + if (!scratches) + return; + + for_each_possible_cpu(i) + vfree(*per_cpu_ptr(scratches, i)); + + free_percpu(scratches); +} + +static void **ipcomp_alloc_scratches(void) +{ + int i; + void **scratches; + + if (ipcomp_scratch_users++) + return ipcomp_scratches; + + scratches = alloc_percpu(void *); + if (!scratches) + return NULL; + + ipcomp_scratches = scratches; + + for_each_possible_cpu(i) { + void *scratch = vmalloc(IPCOMP_SCRATCH_SIZE); + if (!scratch) + return NULL; + *per_cpu_ptr(scratches, i) = scratch; + } + + return scratches; +} + +static void ipcomp_free_tfms(struct crypto_comp **tfms) +{ + struct ipcomp_tfms *pos; + int cpu; + + list_for_each_entry(pos, &ipcomp_tfms_list, list) { + if (pos->tfms == tfms) + break; + } + + BUG_TRAP(pos); + + if (--pos->users) + return; + + list_del(&pos->list); + kfree(pos); + + if (!tfms) + return; + + for_each_possible_cpu(cpu) { + struct crypto_comp *tfm = *per_cpu_ptr(tfms, cpu); + crypto_free_comp(tfm); + } + free_percpu(tfms); +} + +static struct crypto_comp **ipcomp_alloc_tfms(const char *alg_name) +{ + struct ipcomp_tfms *pos; + struct crypto_comp **tfms; + int cpu; + + /* This can be any valid CPU ID so we don't need locking. */ + cpu = raw_smp_processor_id(); + + list_for_each_entry(pos, &ipcomp_tfms_list, list) { + struct crypto_comp *tfm; + + tfms = pos->tfms; + tfm = *per_cpu_ptr(tfms, cpu); + + if (!strcmp(crypto_comp_name(tfm), alg_name)) { + pos->users++; + return tfms; + } + } + + pos = kmalloc(sizeof(*pos), GFP_KERNEL); + if (!pos) + return NULL; + + pos->users = 1; + INIT_LIST_HEAD(&pos->list); + list_add(&pos->list, &ipcomp_tfms_list); + + pos->tfms = tfms = alloc_percpu(struct crypto_comp *); + if (!tfms) + goto error; + + for_each_possible_cpu(cpu) { + struct crypto_comp *tfm = crypto_alloc_comp(alg_name, 0, + CRYPTO_ALG_ASYNC); + if (IS_ERR(tfm)) + goto error; + *per_cpu_ptr(tfms, cpu) = tfm; + } + + return tfms; + +error: + ipcomp_free_tfms(tfms); + return NULL; +} + +static void ipcomp_free_data(struct ipcomp_data *ipcd) +{ + if (ipcd->tfms) + ipcomp_free_tfms(ipcd->tfms); + ipcomp_free_scratches(); +} + +void ipcomp_destroy(struct xfrm_state *x) +{ + struct ipcomp_data *ipcd = x->data; + if (!ipcd) + return; + xfrm_state_delete_tunnel(x); + mutex_lock(&ipcomp_resource_mutex); + ipcomp_free_data(ipcd); + mutex_unlock(&ipcomp_resource_mutex); + kfree(ipcd); +} +EXPORT_SYMBOL_GPL(ipcomp_destroy); + +int ipcomp_init_state(struct xfrm_state *x) +{ + int err; + struct ipcomp_data *ipcd; + struct xfrm_algo_desc *calg_desc; + + err = -EINVAL; + if (!x->calg) + goto out; + + if (x->encap) + goto out; + + err = -ENOMEM; + ipcd = kzalloc(sizeof(*ipcd), GFP_KERNEL); + if (!ipcd) + goto out; + + mutex_lock(&ipcomp_resource_mutex); + if (!ipcomp_alloc_scratches()) + goto error; + + ipcd->tfms = ipcomp_alloc_tfms(x->calg->alg_name); + if (!ipcd->tfms) + goto error; + mutex_unlock(&ipcomp_resource_mutex); + + calg_desc = xfrm_calg_get_byname(x->calg->alg_name, 0); + BUG_ON(!calg_desc); + ipcd->threshold = calg_desc->uinfo.comp.threshold; + x->data = ipcd; + err = 0; +out: + return err; + +error: + ipcomp_free_data(ipcd); + mutex_unlock(&ipcomp_resource_mutex); + kfree(ipcd); + goto out; +} +EXPORT_SYMBOL_GPL(ipcomp_init_state); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) - RFC3173"); +MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>"); 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