summaryrefslogtreecommitdiffstats
path: root/net/ipv4/ip_options.c
diff options
context:
space:
mode:
authorRalf Baechle <ralf@linux-mips.org>1997-04-29 21:13:14 +0000
committer <ralf@linux-mips.org>1997-04-29 21:13:14 +0000
commit19c9bba94152148523ba0f7ef7cffe3d45656b11 (patch)
tree40b1cb534496a7f1ca0f5c314a523c69f1fee464 /net/ipv4/ip_options.c
parent7206675c40394c78a90e74812bbdbf8cf3cca1be (diff)
Import of Linux/MIPS 2.1.36
Diffstat (limited to 'net/ipv4/ip_options.c')
-rw-r--r--net/ipv4/ip_options.c414
1 files changed, 277 insertions, 137 deletions
diff --git a/net/ipv4/ip_options.c b/net/ipv4/ip_options.c
index 517c0e219..2c7974506 100644
--- a/net/ipv4/ip_options.c
+++ b/net/ipv4/ip_options.c
@@ -10,6 +10,7 @@
*/
#include <linux/types.h>
+#include <asm/uaccess.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/icmp.h>
@@ -17,6 +18,7 @@
#include <net/sock.h>
#include <net/ip.h>
#include <net/icmp.h>
+#include <linux/net_alias.h>
/*
* Write options to IP header, record destination address to
@@ -24,30 +26,30 @@
* (we should already know it, so that this function is allowed be
* called only after routing decision) and timestamp,
* if we originate this datagram.
+ *
+ * daddr is real destination address, next hop is recorded in IP header.
+ * saddr is address of outgoing interface.
*/
-void ip_options_build(struct sk_buff * skb, struct options * opt,
- __u32 daddr, __u32 saddr,
- int is_frag)
+void ip_options_build(struct sk_buff * skb, struct ip_options * opt,
+ u32 daddr, u32 saddr, int is_frag)
{
- unsigned char * iph = (unsigned char*)skb->ip_hdr;
+ unsigned char * iph = skb->nh.raw;
- memcpy(skb->proto_priv, opt, sizeof(struct options));
+ memcpy(&(IPCB(skb)->opt), opt, sizeof(struct ip_options));
memcpy(iph+sizeof(struct iphdr), opt->__data, opt->optlen);
- opt = (struct options*)skb->proto_priv;
+ opt = &(IPCB(skb)->opt);
opt->is_data = 0;
if (opt->srr)
memcpy(iph+opt->srr+iph[opt->srr+1]-4, &daddr, 4);
- if (!is_frag)
- {
+ if (!is_frag) {
if (opt->rr_needaddr)
memcpy(iph+opt->rr+iph[opt->rr+2]-5, &saddr, 4);
if (opt->ts_needaddr)
memcpy(iph+opt->ts+iph[opt->ts+2]-9, &saddr, 4);
- if (opt->ts_needtime)
- {
+ if (opt->ts_needtime) {
struct timeval tv;
__u32 midtime;
do_gettimeofday(&tv);
@@ -56,88 +58,96 @@ void ip_options_build(struct sk_buff * skb, struct options * opt,
}
return;
}
- if (opt->rr)
- {
+ if (opt->rr) {
memset(iph+opt->rr, IPOPT_NOP, iph[opt->rr+1]);
opt->rr = 0;
opt->rr_needaddr = 0;
}
- if (opt->ts)
- {
+ if (opt->ts) {
memset(iph+opt->ts, IPOPT_NOP, iph[opt->ts+1]);
opt->ts = 0;
opt->ts_needaddr = opt->ts_needtime = 0;
}
}
-int ip_options_echo(struct options * dopt, struct options * sopt,
- __u32 daddr, __u32 saddr,
- struct sk_buff * skb)
+/*
+ * Provided (sopt, skb) points to received options,
+ * build in dopt compiled option set appropriate for answering.
+ * i.e. invert SRR option, copy anothers,
+ * and grab room in RR/TS options.
+ *
+ * NOTE: dopt cannot point to skb.
+ */
+
+int ip_options_echo(struct ip_options * dopt, struct sk_buff * skb)
{
+ struct ip_options *sopt;
unsigned char *sptr, *dptr;
int soffset, doffset;
int optlen;
+ u32 daddr;
- memset(dopt, 0, sizeof(struct options));
+#if 111
+ if (skb == NULL) {
+ printk(KERN_DEBUG "no skb in ip_options_echo\n");
+ return -EINVAL;
+ }
+#endif
+ memset(dopt, 0, sizeof(struct ip_options));
dopt->is_data = 1;
- if (!sopt)
- sopt = (struct options*)skb->proto_priv;
+ sopt = &(IPCB(skb)->opt);
- if (sopt->optlen == 0)
- {
+ if (sopt->optlen == 0) {
dopt->optlen = 0;
return 0;
}
- sptr = (sopt->is_data ? sopt->__data - sizeof(struct iphdr) :
- (unsigned char *)skb->ip_hdr);
+ sptr = skb->nh.raw;
dptr = dopt->__data;
- if (sopt->rr)
- {
+ if (skb->dst)
+ daddr = ((struct rtable*)skb->dst)->rt_spec_dst;
+ else
+ daddr = skb->nh.iph->daddr;
+
+ if (sopt->rr) {
optlen = sptr[sopt->rr+1];
soffset = sptr[sopt->rr+2];
dopt->rr = dopt->optlen + sizeof(struct iphdr);
memcpy(dptr, sptr+sopt->rr, optlen);
if (sopt->rr_needaddr && soffset <= optlen) {
if (soffset + 3 > optlen)
- return -EINVAL;
+ return -EINVAL;
dptr[2] = soffset + 4;
dopt->rr_needaddr = 1;
}
- dptr += optlen;
+ dptr += optlen;
dopt->optlen += optlen;
}
- if (sopt->ts)
- {
+ if (sopt->ts) {
optlen = sptr[sopt->ts+1];
soffset = sptr[sopt->ts+2];
dopt->ts = dopt->optlen + sizeof(struct iphdr);
memcpy(dptr, sptr+sopt->ts, optlen);
- if (soffset <= optlen)
- {
- if (sopt->ts_needaddr)
- {
+ if (soffset <= optlen) {
+ if (sopt->ts_needaddr) {
if (soffset + 3 > optlen)
return -EINVAL;
dopt->ts_needaddr = 1;
soffset += 4;
}
- if (sopt->ts_needtime)
- {
+ if (sopt->ts_needtime) {
if (soffset + 3 > optlen)
return -EINVAL;
dopt->ts_needtime = 1;
soffset += 4;
}
- if (((struct timestamp*)(dptr+1))->flags == IPOPT_TS_PRESPEC)
- {
+ if (((struct timestamp*)(dptr+1))->flags == IPOPT_TS_PRESPEC) {
__u32 addr;
memcpy(&addr, sptr+soffset-9, 4);
- if (ip_chk_addr(addr) == 0)
- {
+ if (__ip_chk_addr(addr) == 0) {
dopt->ts_needtime = 0;
dopt->ts_needaddr = 0;
soffset -= 8;
@@ -148,10 +158,9 @@ int ip_options_echo(struct options * dopt, struct options * sopt,
dptr += optlen;
dopt->optlen += optlen;
}
- if (sopt->srr)
- {
+ if (sopt->srr) {
unsigned char * start = sptr+sopt->srr;
- __u32 faddr;
+ u32 faddr;
optlen = start[1];
soffset = start[2];
@@ -159,19 +168,17 @@ int ip_options_echo(struct options * dopt, struct options * sopt,
if (soffset > optlen)
soffset = optlen + 1;
soffset -= 4;
- if (soffset > 3)
- {
+ if (soffset > 3) {
memcpy(&faddr, &start[soffset-1], 4);
for (soffset-=4, doffset=4; soffset > 3; soffset-=4, doffset+=4)
memcpy(&dptr[doffset-1], &start[soffset-1], 4);
/*
* RFC1812 requires to fix illegal source routes.
*/
- if (memcmp(&saddr, &start[soffset+3], 4) == 0)
+ if (memcmp(&skb->nh.iph->saddr, &start[soffset+3], 4) == 0)
doffset -= 4;
}
- if (doffset > 3)
- {
+ if (doffset > 3) {
memcpy(&start[doffset-1], &daddr, 4);
dopt->faddr = faddr;
dptr[0] = start[0];
@@ -183,28 +190,31 @@ int ip_options_echo(struct options * dopt, struct options * sopt,
dopt->is_strictroute = sopt->is_strictroute;
}
}
- while (dopt->optlen & 3)
- {
+ while (dopt->optlen & 3) {
*dptr++ = IPOPT_END;
dopt->optlen++;
}
return 0;
}
+/*
+ * Options "fragmenting", just fill options not
+ * allowed in fragments with NOOPs.
+ * Simple and stupid 8), but the most efficient way.
+ */
+
void ip_options_fragment(struct sk_buff * skb)
{
- unsigned char * optptr = (unsigned char*)skb->ip_hdr;
- struct options * opt = (struct options*)skb->proto_priv;
+ unsigned char * optptr = skb->nh.raw;
+ struct ip_options * opt = &(IPCB(skb)->opt);
int l = opt->optlen;
int optlen;
- while (l > 0)
- {
- switch (*optptr)
- {
- case IPOPT_END:
+ while (l > 0) {
+ switch (*optptr) {
+ case IPOPT_END:
return;
- case IPOPT_NOOP:
+ case IPOPT_NOOP:
l--;
optptr++;
continue;
@@ -212,7 +222,7 @@ void ip_options_fragment(struct sk_buff * skb)
optlen = optptr[1];
if (optlen<2 || optlen>l)
return;
- if (!(*optptr & 0x80))
+ if (!IPOPT_COPIED(*optptr))
memset(optptr, IPOPT_NOOP, optlen);
l -= optlen;
optptr += optlen;
@@ -231,7 +241,7 @@ void ip_options_fragment(struct sk_buff * skb)
* If opt == NULL, then skb->data should point to IP header.
*/
-int ip_options_compile(struct options * opt, struct sk_buff * skb)
+int ip_options_compile(struct ip_options * opt, struct sk_buff * skb)
{
int l;
unsigned char * iph;
@@ -239,30 +249,23 @@ int ip_options_compile(struct options * opt, struct sk_buff * skb)
int optlen;
unsigned char * pp_ptr = NULL;
- if (!opt)
- {
- opt = (struct options*)skb->proto_priv;
- memset(opt, 0, sizeof(struct options));
- iph = (unsigned char*)skb->ip_hdr;
+ if (!opt) {
+ opt = &(IPCB(skb)->opt);
+ memset(opt, 0, sizeof(struct ip_options));
+ iph = skb->nh.raw;
opt->optlen = ((struct iphdr *)iph)->ihl*4 - sizeof(struct iphdr);
optptr = iph + sizeof(struct iphdr);
opt->is_data = 0;
- }
- else
- {
- optptr = opt->is_data ? opt->__data : (unsigned char*)&skb->ip_hdr[1];
+ } else {
+ optptr = opt->is_data ? opt->__data : (unsigned char*)&(skb->nh.iph[1]);
iph = optptr - sizeof(struct iphdr);
}
- for (l = opt->optlen; l > 0; )
- {
- switch (*optptr)
- {
+ for (l = opt->optlen; l > 0; ) {
+ switch (*optptr) {
case IPOPT_END:
- for (optptr++, l--; l>0; l--)
- {
- if (*optptr != IPOPT_END)
- {
+ for (optptr++, l--; l>0; l--) {
+ if (*optptr != IPOPT_END) {
*optptr = IPOPT_END;
opt->is_changed = 1;
}
@@ -274,35 +277,28 @@ int ip_options_compile(struct options * opt, struct sk_buff * skb)
continue;
}
optlen = optptr[1];
- if (optlen<2 || optlen>l)
- {
+ if (optlen<2 || optlen>l) {
pp_ptr = optptr;
goto error;
}
- switch (*optptr)
- {
+ switch (*optptr) {
case IPOPT_SSRR:
case IPOPT_LSRR:
- if (optlen < 3)
- {
+ if (optlen < 3) {
pp_ptr = optptr + 1;
goto error;
}
- if (optptr[2] < 4)
- {
+ if (optptr[2] < 4) {
pp_ptr = optptr + 2;
goto error;
}
/* NB: cf RFC-1812 5.2.4.1 */
- if (opt->srr)
- {
+ if (opt->srr) {
pp_ptr = optptr;
goto error;
}
- if (!skb)
- {
- if (optptr[2] != 4 || optlen < 7 || ((optlen-3) & 3))
- {
+ if (!skb) {
+ if (optptr[2] != 4 || optlen < 7 || ((optlen-3) & 3)) {
pp_ptr = optptr + 1;
goto error;
}
@@ -314,30 +310,24 @@ int ip_options_compile(struct options * opt, struct sk_buff * skb)
opt->srr = optptr - iph;
break;
case IPOPT_RR:
- if (opt->rr)
- {
+ if (opt->rr) {
pp_ptr = optptr;
goto error;
}
- if (optlen < 3)
- {
+ if (optlen < 3) {
pp_ptr = optptr + 1;
goto error;
}
- if (optptr[2] < 4)
- {
+ if (optptr[2] < 4) {
pp_ptr = optptr + 2;
goto error;
}
- if (optptr[2] <= optlen)
- {
- if (optptr[2]+3 > optlen)
- {
+ if (optptr[2] <= optlen) {
+ if (optptr[2]+3 > optlen) {
pp_ptr = optptr + 2;
goto error;
}
- if (skb)
- {
+ if (skb) {
memcpy(&optptr[optptr[2]-1], &skb->dev->pa_addr, 4);
opt->is_changed = 1;
}
@@ -347,32 +337,26 @@ int ip_options_compile(struct options * opt, struct sk_buff * skb)
opt->rr = optptr - iph;
break;
case IPOPT_TIMESTAMP:
- if (opt->ts)
- {
+ if (opt->ts) {
pp_ptr = optptr;
goto error;
}
- if (optlen < 4)
- {
+ if (optlen < 4) {
pp_ptr = optptr + 1;
goto error;
}
- if (optptr[2] < 5)
- {
+ if (optptr[2] < 5) {
pp_ptr = optptr + 2;
goto error;
}
- if (optptr[2] <= optlen)
- {
+ if (optptr[2] <= optlen) {
struct timestamp * ts = (struct timestamp*)(optptr+1);
__u32 * timeptr = NULL;
- if (ts->ptr+3 > ts->len)
- {
+ if (ts->ptr+3 > ts->len) {
pp_ptr = optptr + 2;
goto error;
}
- switch (ts->flags)
- {
+ switch (ts->flags) {
case IPOPT_TS_TSONLY:
opt->ts = optptr - iph;
if (skb)
@@ -381,14 +365,12 @@ int ip_options_compile(struct options * opt, struct sk_buff * skb)
ts->ptr += 4;
break;
case IPOPT_TS_TSANDADDR:
- if (ts->ptr+7 > ts->len)
- {
+ if (ts->ptr+7 > ts->len) {
pp_ptr = optptr + 2;
goto error;
}
opt->ts = optptr - iph;
- if (skb)
- {
+ if (skb) {
memcpy(&optptr[ts->ptr-1], &skb->dev->pa_addr, 4);
timeptr = (__u32*)&optptr[ts->ptr+3];
}
@@ -397,16 +379,15 @@ int ip_options_compile(struct options * opt, struct sk_buff * skb)
ts->ptr += 8;
break;
case IPOPT_TS_PRESPEC:
- if (ts->ptr+7 > ts->len)
- {
+ if (ts->ptr+7 > ts->len) {
pp_ptr = optptr + 2;
goto error;
}
opt->ts = optptr - iph;
{
- __u32 addr;
+ u32 addr;
memcpy(&addr, &optptr[ts->ptr-1], 4);
- if (ip_chk_addr(addr) == 0)
+ if (__ip_chk_addr(addr) == 0)
break;
if (skb)
timeptr = (__u32*)&optptr[ts->ptr+3];
@@ -419,8 +400,7 @@ int ip_options_compile(struct options * opt, struct sk_buff * skb)
pp_ptr = optptr + 3;
goto error;
}
- if (timeptr)
- {
+ if (timeptr) {
struct timeval tv;
__u32 midtime;
do_gettimeofday(&tv);
@@ -428,28 +408,31 @@ int ip_options_compile(struct options * opt, struct sk_buff * skb)
memcpy(timeptr, &midtime, sizeof(__u32));
opt->is_changed = 1;
}
- }
- else
- {
+ } else {
struct timestamp * ts = (struct timestamp*)(optptr+1);
- if (ts->overflow == 15)
- {
+ if (ts->overflow == 15) {
pp_ptr = optptr + 3;
goto error;
}
opt->ts = optptr - iph;
- if (skb)
- {
+ if (skb) {
ts->overflow++;
opt->is_changed = 1;
}
}
break;
+ case IPOPT_RA:
+ if (optlen < 4) {
+ pp_ptr = optptr + 1;
+ goto error;
+ }
+ if (optptr[2] == 0 && optptr[3] == 0)
+ opt->router_alert = optptr - iph;
+ break;
case IPOPT_SEC:
case IPOPT_SID:
default:
- if (!skb)
- {
+ if (!skb) {
pp_ptr = optptr;
goto error;
}
@@ -464,11 +447,168 @@ eol:
return 0;
error:
- if (skb)
- {
- icmp_send(skb, ICMP_PARAMETERPROB, 0, pp_ptr-iph, skb->dev);
+ if (skb) {
+ icmp_send(skb, ICMP_PARAMETERPROB, 0, pp_ptr-iph);
kfree_skb(skb, FREE_READ);
}
return -EINVAL;
}
+
+/*
+ * Undo all the changes done by ip_options_compile().
+ */
+
+void ip_options_undo(struct ip_options * opt)
+{
+ if (opt->srr) {
+ unsigned char * optptr = opt->__data+opt->srr-sizeof(struct iphdr);
+ memmove(optptr+7, optptr+3, optptr[1]-7);
+ memcpy(optptr+3, &opt->faddr, 4);
+ }
+ if (opt->rr_needaddr) {
+ unsigned char * optptr = opt->__data+opt->rr-sizeof(struct iphdr);
+ memset(&optptr[optptr[2]-1], 0, 4);
+ optptr[2] -= 4;
+ }
+ if (opt->ts) {
+ unsigned char * optptr = opt->__data+opt->ts-sizeof(struct iphdr);
+ if (opt->ts_needtime) {
+ memset(&optptr[optptr[2]-1], 0, 4);
+ optptr[2] -= 4;
+ }
+ if (opt->ts_needaddr) {
+ memset(&optptr[optptr[2]-1], 0, 4);
+ optptr[2] -= 4;
+ }
+ }
+}
+
+int ip_options_get(struct ip_options **optp, unsigned char *data, int optlen, int user)
+{
+ struct ip_options *opt;
+
+ opt = kmalloc(sizeof(struct ip_options)+((optlen+3)&~3), GFP_KERNEL);
+ if (!opt)
+ return -ENOMEM;
+ memset(opt, 0, sizeof(struct ip_options));
+ if (optlen) {
+ if (user) {
+ if (copy_from_user(opt->__data, data, optlen))
+ return -EFAULT;
+ } else
+ memcpy(opt->__data, data, optlen);
+ }
+ while (optlen & 3)
+ opt->__data[optlen++] = IPOPT_END;
+ opt->optlen = optlen;
+ opt->is_data = 1;
+ opt->is_setbyuser = 1;
+ if (optlen && ip_options_compile(opt, NULL)) {
+ kfree_s(opt, sizeof(struct options) + optlen);
+ return -EINVAL;
+ }
+ *optp = opt;
+ return 0;
+}
+
+void ip_forward_options(struct sk_buff *skb)
+{
+ struct ip_options * opt = &(IPCB(skb)->opt);
+ unsigned char * optptr;
+ struct rtable *rt = (struct rtable*)skb->dst;
+ unsigned char *raw = skb->nh.raw;
+
+ if (opt->rr_needaddr) {
+ optptr = (unsigned char *)raw + opt->rr;
+ memcpy(&optptr[optptr[2]-5], &rt->u.dst.dev->pa_addr, 4);
+ opt->is_changed = 1;
+ }
+ if (opt->srr_is_hit) {
+ int srrptr, srrspace;
+
+ optptr = raw + opt->srr;
+
+ for ( srrptr=optptr[2], srrspace = optptr[1];
+ srrptr <= srrspace;
+ srrptr += 4
+ ) {
+ if (srrptr + 3 > srrspace)
+ break;
+ if (memcmp(&rt->rt_dst, &optptr[srrptr-1], 4) == 0)
+ break;
+ }
+ if (srrptr + 3 <= srrspace) {
+ opt->is_changed = 1;
+ memcpy(&optptr[srrptr-1], &rt->u.dst.dev->pa_addr, 4);
+ skb->nh.iph->daddr = rt->rt_dst;
+ optptr[2] = srrptr+4;
+ } else
+ printk(KERN_CRIT "ip_forward(): Argh! Destination lost!\n");
+ if (opt->ts_needaddr) {
+ optptr = raw + opt->ts;
+ memcpy(&optptr[optptr[2]-9], &rt->u.dst.dev->pa_addr, 4);
+ opt->is_changed = 1;
+ }
+ if (opt->is_changed) {
+ opt->is_changed = 0;
+ ip_send_check(skb->nh.iph);
+ }
+ }
+}
+
+int ip_options_rcv_srr(struct sk_buff *skb)
+{
+ struct ip_options *opt = &(IPCB(skb)->opt);
+ int srrspace, srrptr;
+ u32 nexthop;
+ struct iphdr *iph = skb->nh.iph;
+ unsigned char * optptr = skb->nh.raw + opt->srr;
+ struct rtable *rt = (struct rtable*)skb->dst;
+ struct rtable *rt2;
+ int err;
+
+ if (!opt->srr)
+ return 0;
+
+ if (rt->rt_flags&(RTF_BROADCAST|RTF_MULTICAST|RTF_NAT)
+ || skb->pkt_type != PACKET_HOST)
+ return -EINVAL;
+
+ if (!(rt->rt_flags & RTF_LOCAL)) {
+ if (!opt->is_strictroute)
+ return 0;
+ icmp_send(skb, ICMP_PARAMETERPROB, 0, 16);
+ return -EINVAL;
+ }
+
+ for (srrptr=optptr[2], srrspace = optptr[1]; srrptr <= srrspace; srrptr += 4) {
+ if (srrptr + 3 > srrspace) {
+ icmp_send(skb, ICMP_PARAMETERPROB, 0, opt->srr+2);
+ return -EINVAL;
+ }
+ memcpy(&nexthop, &optptr[srrptr-1], 4);
+
+ rt = (struct rtable*)skb->dst;
+ skb->dst = NULL;
+ err = ip_route_input(skb, nexthop, iph->saddr, iph->tos,
+ net_alias_main_dev(skb->dev));
+ rt2 = (struct rtable*)skb->dst;
+ if (err || rt2->rt_flags&(RTF_BROADCAST|RTF_MULTICAST|RTF_NAT)) {
+ ip_rt_put(rt2);
+ skb->dst = &rt->u.dst;
+ return -EINVAL;
+ }
+ ip_rt_put(rt);
+ if (!(rt2->rt_flags&RTF_LOCAL))
+ break;
+ /* Superfast 8) loopback forward */
+ memcpy(&iph->daddr, &optptr[srrptr-1], 4);
+ opt->is_changed = 1;
+ }
+ if (srrptr <= srrspace) {
+ opt->srr_is_hit = 1;
+ opt->is_changed = 1;
+ }
+ return 0;
+}