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my-os-project2/kernel/picotcp/modules/pico_olsr.c
kamkow1 815c2239fe Porting PicoTCP WIP
2025-10-29 14:29:06 +01:00

1168 lines
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/*********************************************************************
PicoTCP. Copyright (c) 2012-2017 Altran Intelligent Systems. Some rights reserved.
See COPYING, LICENSE.GPLv2 and LICENSE.GPLv3 for usage.
Authors: Daniele Lacamera
********************************************************************/
#include "pico_stack.h"
#include "pico_config.h"
#include "pico_device.h"
#include "pico_ipv4.h"
#include "pico_arp.h"
#include "pico_socket.h"
#include "pico_olsr.h"
#ifdef PICO_SUPPORT_OLSR
#define DGRAM_MAX_SIZE (100 - 28)
#define MAX_OLSR_MEM (4 * DGRAM_MAX_SIZE)
#ifdef DEBUG_OLSR
#define olsr_dbg dbg
#else
#define olsr_dbg(...) do {} while(0)
#endif
int OOM(void);
#define OLSR_HELLO_INTERVAL ((uint32_t)5000)
#define OLSR_TC_INTERVAL ((uint32_t)9000)
#define OLSR_MAXJITTER ((uint32_t)(OLSR_HELLO_INTERVAL >> 2))
static const struct pico_ip4 HOST_NETMASK = {
0xffffffff
};
#ifndef MIN
# define MIN(a, b) (a < b ? a : b)
#endif
#define fresher(a, b) ((a > b) || ((b - a) > 32768))
static uint16_t msg_counter; /* Global message sequence number */
/* Objects */
struct olsr_dev_entry
{
struct olsr_dev_entry *next;
struct pico_device *dev;
uint16_t pkt_counter;
};
/* OLSR Protocol */
#define OLSRMSG_HELLO 0xc9
#define OLSRMSG_MID 0x03
#define OLSRMSG_TC 0xca
#define OLSRLINK_SYMMETRIC 0x06
#define OLSRLINK_UNKNOWN 0x08
#define OLSRLINK_MPR 0x0a
#define OLSR_PORT (short_be((uint16_t)698))
/* Headers */
PACKED_STRUCT_DEF olsr_link
{
uint8_t link_code;
uint8_t reserved;
uint16_t link_msg_size;
};
PACKED_STRUCT_DEF olsr_neighbor
{
uint32_t addr;
uint8_t lq;
uint8_t nlq;
uint16_t reserved;
};
PACKED_STRUCT_DEF olsr_hmsg_hello
{
uint16_t reserved;
uint8_t htime;
uint8_t willingness;
};
PACKED_STRUCT_DEF olsr_hmsg_tc
{
uint16_t ansn;
uint16_t reserved;
};
PACKED_STRUCT_DEF olsrmsg
{
uint8_t type;
uint8_t vtime;
uint16_t size;
struct pico_ip4 orig;
uint8_t ttl;
uint8_t hop;
uint16_t seq;
};
PACKED_STRUCT_DEF olsrhdr
{
uint16_t len;
uint16_t seq;
};
/* Globals */
static struct pico_socket *udpsock = NULL;
uint16_t my_ansn = 0;
static struct olsr_route_entry *Local_interfaces = NULL;
static struct olsr_dev_entry *Local_devices = NULL;
static struct olsr_dev_entry *olsr_get_deventry(struct pico_device *dev)
{
struct olsr_dev_entry *cur = Local_devices;
while(cur) {
if (cur->dev == dev)
return cur;
cur = cur->next;
}
return NULL;
}
struct olsr_route_entry *olsr_get_ethentry(struct pico_device *vif)
{
struct olsr_route_entry *cur = Local_interfaces;
while(cur) {
if (cur->iface == vif)
return cur;
cur = cur->next;
}
return NULL;
}
static struct olsr_route_entry *get_next_hop(struct olsr_route_entry *dst)
{
struct olsr_route_entry *hop = dst;
while(hop) {
/* olsr_dbg("Finding next hop to %08x m=%d\n", hop->destination.addr, hop->metric); */
if(hop->metric <= 1)
return hop;
hop = hop->gateway;
}
return NULL;
}
static inline void olsr_route_add(struct olsr_route_entry *el)
{
/* char dest[16],nxdest[16]; */
struct olsr_route_entry *nexthop;
if(!el)
return;
my_ansn++;
nexthop = get_next_hop(el);
if (el->gateway && nexthop && (nexthop->destination.addr != el->destination.addr)) {
/* 2-hops route or more */
el->next = el->gateway->children;
el->gateway->children = el;
el->link_type = OLSRLINK_MPR;
olsr_dbg("[OLSR] ----------Adding route to %08x via %08x metric %d\n", el->destination.addr, nexthop->destination.addr, el->metric);
pico_ipv4_route_add(el->destination, HOST_NETMASK, nexthop->destination, (int) el->metric, NULL);
} else if (el->iface) {
/* neighbor */
struct olsr_route_entry *ei = olsr_get_ethentry(el->iface);
struct pico_ip4 no_gw = {
0U
};
if (el->link_type == OLSRLINK_UNKNOWN)
el->link_type = OLSRLINK_SYMMETRIC;
if (ei) {
el->next = ei->children;
ei->children = el;
}
olsr_dbg("[OLSR] ----------Adding neighbor %08x iface %s\n", el->destination.addr, el->iface->name);
pico_ipv4_route_add(el->destination, HOST_NETMASK, no_gw, 1, pico_ipv4_link_by_dev(el->iface));
}
}
static inline void olsr_route_del(struct olsr_route_entry *r)
{
struct olsr_route_entry *cur, *prev = NULL, *lst;
/* olsr_dbg("[OLSR] DELETING route..................\n"); */
my_ansn++;
if (r->gateway) {
lst = r->gateway->children;
} else if (r->iface) {
lst = olsr_get_ethentry(r->iface);
} else {
lst = Local_interfaces;
}
cur = lst, prev = NULL;
while(cur) {
if (cur == r) {
/* found */
if (r->gateway) {
pico_ipv4_route_del(r->destination, HOST_NETMASK, r->metric);
olsr_dbg("[OLSR] Deleting route to %08x \n", r->destination.addr);
if (!prev)
r->gateway->children = r->next;
else
prev->next = r->next;
}
while (r->children) {
olsr_route_del(r->children);
/* Orphans must die. */
/* PICO_FREE(r->children); */
}
return;
}
prev = cur;
cur = cur->next;
}
}
static struct olsr_route_entry *get_route_by_address(struct olsr_route_entry *lst, uint32_t ip)
{
struct olsr_route_entry *found;
if(lst) {
if (lst->destination.addr == ip) {
return lst;
}
/* recursive function, could be dangerous for stack overflow if a lot of routes are available... */
found = get_route_by_address(lst->children, ip);
if (found)
return found;
found = get_route_by_address(lst->next, ip);
if (found)
return found;
}
return NULL;
}
#define OLSR_C_SHIFT (uint32_t)4 /* 1/16 */
#define DEFAULT_VTIME 288UL
static uint8_t seconds2olsr(uint32_t seconds)
{
uint16_t a, b;
/* olsr_dbg("seconds=%u\n", (uint16_t)seconds); */
if (seconds > 32767)
seconds = 32767;
/* find largest b such as seconds/C >= 2^b */
for (b = 1; b <= 0x0fu; b++) {
if ((uint16_t)(seconds * 16u) < (1u << b)) {
b--;
break;
}
}
/* olsr_dbg("b=%u", b); */
/* compute the expression 16*(T/(C*(2^b))-1), which may not be a
integer, and round it up. This results in the value for 'a' */
/* a = (T / ( C * (1u << b) ) ) - 1u; */
{
uint16_t den = ((uint16_t)(1u << b) >> 4u);
/* olsr_dbg(" den=%u ", den); */
if (den == 0)
{
/* olsr_dbg("div by 0!\n"); */
den = 1u;
}
a = (uint16_t)(((uint16_t)seconds / den) - (uint16_t)1);
}
/* a = a & 0x0Fu; */
/* olsr_dbg(" a=%u\n", a); */
/* if 'a' is equal to 16: increment 'b' by one, and set 'a' to 0 */
if (16u == a) {
b++;
a = 0u;
}
return (uint8_t)((a << 4u) + b);
}
static uint32_t olsr2seconds(uint8_t olsr)
{
uint8_t a, b;
uint16_t seconds;
/* olsr_dbg("olsr format: %u -- ", olsr); */
a = (olsr >> 4) & 0xFu;
b = olsr & 0x0f;
/* olsr_dbg("o2s: a=%u, b=%u\n", a,b); */
if (b < 4)
seconds = (uint16_t)(((1u << b) + (uint16_t)(((uint16_t)(a << b) >> 4u) & 0xFu)) >> OLSR_C_SHIFT);
else
seconds = (uint16_t)(((1u << b) + (uint16_t)(((uint16_t)(a << (b - 4))) & 0xFu)) >> OLSR_C_SHIFT);
/* olsr_dbg("o2s: seconds: %u\n", seconds); */
return seconds;
}
static void olsr_garbage_collector(struct olsr_route_entry *sublist)
{
if(!sublist)
return;
if (sublist->time_left <= 0) {
olsr_route_del(sublist);
PICO_FREE(sublist);
return;
} else {
/* sublist->time_left -= 2u; */
sublist->time_left -= 8u;
}
olsr_garbage_collector(sublist->children);
olsr_garbage_collector(sublist->next);
}
struct olsr_fwd_pkt
{
void *buf;
uint16_t len;
struct pico_device *pdev;
};
static uint32_t buffer_mem_used = 0U;
static void olsr_process_out(pico_time now, void *arg)
{
struct olsr_fwd_pkt *p = (struct olsr_fwd_pkt *)arg;
struct pico_ip4 bcast;
struct pico_ipv4_link *addr;
struct olsr_dev_entry *pdev = Local_devices;
struct olsrhdr *ohdr;
(void)now;
/* Send the thing out */
ohdr = (struct olsrhdr *)p->buf;
ohdr->len = short_be((uint16_t)p->len);
if (p->pdev) {
struct olsr_dev_entry *odev = olsr_get_deventry(p->pdev);
if (!odev) {
goto out_free;
}
addr = pico_ipv4_link_by_dev(p->pdev);
if (!addr)
goto out_free;
ohdr->seq = short_be((uint16_t)(odev->pkt_counter)++);
if (addr->address.addr)
bcast.addr = (addr->netmask.addr & addr->address.addr) | (~addr->netmask.addr);
else
bcast.addr = 0xFFFFFFFFu;
if ( 0 > pico_socket_sendto(udpsock, p->buf, p->len, &bcast, OLSR_PORT)) {
olsr_dbg("olsr send\n");
}
} else {
while(pdev) {
ohdr->seq = short_be((uint16_t)(pdev->pkt_counter++));
addr = pico_ipv4_link_by_dev(pdev->dev);
if (!addr)
continue;
if (addr->address.addr)
bcast.addr = (addr->netmask.addr & addr->address.addr) | (~addr->netmask.addr);
else
bcast.addr = 0xFFFFFFFFu;
if ( 0 > pico_socket_sendto(udpsock, p->buf, p->len, &bcast, OLSR_PORT)) {
olsr_dbg("olsr send\n");
}
pdev = pdev->next;
}
}
out_free:
PICO_FREE(p->buf); /* XXX <-- broken? */
buffer_mem_used -= DGRAM_MAX_SIZE;
PICO_FREE(p);
}
static void olsr_scheduled_output(uint32_t when, void *buffer, uint16_t size, struct pico_device *pdev)
{
struct olsr_fwd_pkt *p;
/* olsr_dbg("Scheduling olsr packet, type:%s, size: %x\n", when == OLSR_HELLO_INTERVAL?"HELLO":"TC", size); */
if ((buffer_mem_used + DGRAM_MAX_SIZE) > MAX_OLSR_MEM) {
PICO_FREE(buffer);
return;
}
p = PICO_ZALLOC(sizeof(struct olsr_fwd_pkt));
if (!p) {
OOM();
PICO_FREE(buffer);
return;
}
p->buf = buffer;
p->len = size;
p->pdev = pdev;
buffer_mem_used += DGRAM_MAX_SIZE;
if (!pico_timer_add(1 + when - ((pico_rand() % OLSR_MAXJITTER)), &olsr_process_out, p)) {
olsr_dbg("OLSR: Failed to start process timer\n");
OOM();
PICO_FREE(p);
PICO_FREE(buffer);
}
}
static void refresh_routes(void)
{
struct olsr_route_entry *local;
struct olsr_dev_entry *icur = Local_devices;
/* Refresh local entries */
/* Step 1: set zero expire time for local addresses and neighbors*/
local = Local_interfaces;
while(local) {
local = local->next;
}
/* Step 2: refresh timer for entries that are still valid.
* Add new entries.
*/
while(icur) {
struct pico_ipv4_link *lnk = NULL;
do {
lnk = pico_ipv4_link_by_dev_next(icur->dev, lnk);
if (!lnk) break;
local = olsr_get_ethentry(icur->dev);
if (local) {
local->time_left = (OLSR_HELLO_INTERVAL << 2);
} else if (lnk) {
struct olsr_route_entry *e = PICO_ZALLOC(sizeof (struct olsr_route_entry));
if (!e) {
olsr_dbg("olsr: adding local route entry\n");
OOM();
return;
}
e->destination.addr = lnk->address.addr; /* Always pick the first address */
e->time_left = (OLSR_HELLO_INTERVAL << 2);
e->iface = icur->dev;
e->metric = 0;
e->lq = 0xFF;
e->nlq = 0xFF;
e->next = Local_interfaces;
Local_interfaces = e;
}
} while (lnk);
/* disabled if device type != eth */
/* refresh_neighbors(icur->dev); */
icur = icur->next;
}
}
static uint32_t olsr_build_hello_neighbors(uint8_t *buf, uint32_t size, struct olsr_route_entry **bookmark)
{
uint32_t ret = 0;
struct olsr_route_entry *local, *neighbor;
struct olsr_neighbor *dst = (struct olsr_neighbor *) buf;
uint32_t total_link_size = sizeof(struct olsr_neighbor) + sizeof(struct olsr_link);
local = Local_interfaces;
while (local) {
neighbor = local->children;
if (*bookmark) {
while ((neighbor) && *bookmark != neighbor)
neighbor = neighbor->next;
}
while (neighbor) {
struct olsr_link *li = (struct olsr_link *) (buf + ret);
if ((size - ret) < total_link_size) {
/* Incomplete list, new datagram needed. */
*bookmark = neighbor;
return ret;
}
li->link_code = neighbor->link_type;
li->reserved = 0;
li->link_msg_size = short_be((uint16_t)total_link_size);
ret += (uint32_t)sizeof(struct olsr_link);
dst = (struct olsr_neighbor *) (buf + ret);
dst->addr = neighbor->destination.addr;
dst->nlq = neighbor->nlq;
dst->lq = neighbor->lq;
dst->reserved = 0;
ret += (uint32_t)sizeof(struct olsr_neighbor);
neighbor = neighbor->next;
}
local = local->next;
}
*bookmark = NULL; /* All the list was visited, no more dgrams needed */
return ret;
}
static uint32_t olsr_build_tc_neighbors(uint8_t *buf, uint32_t size, struct olsr_route_entry **bookmark)
{
uint32_t ret = 0;
struct olsr_route_entry *local, *neighbor;
struct olsr_neighbor *dst = (struct olsr_neighbor *) buf;
local = Local_interfaces;
while (local) {
neighbor = local->children;
if (*bookmark) {
while ((neighbor) && *bookmark != neighbor)
neighbor = neighbor->next;
}
while (neighbor) {
if (size - ret < sizeof(struct olsr_neighbor)) {
/* Incomplete list, new datagram needed. */
*bookmark = neighbor;
return ret;
}
dst->addr = neighbor->destination.addr;
dst->nlq = neighbor->nlq;
dst->lq = neighbor->lq;
dst->reserved = 0;
ret += (uint32_t)sizeof(struct olsr_neighbor);
dst = (struct olsr_neighbor *) (buf + ret);
neighbor = neighbor->next;
}
local = local->next;
}
*bookmark = NULL; /* All the list was visited, no more dgrams needed */
return ret;
}
static uint32_t olsr_build_mid(uint8_t *buf, uint32_t size, struct pico_device *excluded)
{
uint32_t ret = 0;
struct olsr_route_entry *local;
struct pico_ip4 *dst = (struct pico_ip4 *) buf;
local = Local_interfaces;
while (local) {
if (local->iface != excluded) {
dst->addr = local->destination.addr;
ret += (uint32_t)sizeof(uint32_t);
dst = (struct pico_ip4 *) (buf + ret);
if (ret >= size)
return (uint32_t)(ret - sizeof(uint32_t));
}
local = local->next;
}
return ret;
}
static void olsr_compose_tc_dgram(struct pico_device *pdev, struct pico_ipv4_link *ep)
{
struct olsrmsg *msg_tc, *msg_mid;
uint32_t size = 0, r;
struct olsr_route_entry *last_neighbor = NULL;
uint8_t *dgram;
struct olsr_hmsg_tc *tc;
do {
dgram = PICO_ZALLOC(DGRAM_MAX_SIZE);
if (!dgram) {
OOM();
return;
}
size = (uint32_t)sizeof(struct olsrhdr);
ep = pico_ipv4_link_by_dev(pdev);
if (!ep) {
PICO_FREE(dgram);
return;
}
if (!last_neighbor) {
/* MID Message */
msg_mid = (struct olsrmsg *)(dgram + size);
size += (uint32_t)sizeof(struct olsrmsg);
msg_mid->type = OLSRMSG_MID;
msg_mid->vtime = seconds2olsr(60);
msg_mid->orig.addr = ep->address.addr;
msg_mid->ttl = 0xFF;
msg_mid->hop = 0;
msg_mid->seq = short_be(msg_counter++);
r = olsr_build_mid(dgram + size, DGRAM_MAX_SIZE - size, pdev);
if (r == 0) {
size -= (uint32_t)sizeof(struct olsrmsg);
} else {
if ((size + r) > DGRAM_MAX_SIZE)
return;
size += r;
msg_mid->size = short_be((uint16_t)(sizeof(struct olsrmsg) + r));
}
}
if (size + sizeof(struct olsrmsg) > DGRAM_MAX_SIZE)
return;
msg_tc = (struct olsrmsg *) (dgram + size);
size += (uint32_t)sizeof(struct olsrmsg);
msg_tc->type = OLSRMSG_TC;
msg_tc->vtime = seconds2olsr(DEFAULT_VTIME);
msg_tc->orig.addr = ep->address.addr;
msg_tc->ttl = 0xFF;
msg_tc->hop = 0;
msg_tc->seq = short_be(msg_counter++);
tc = (struct olsr_hmsg_tc *)(dgram + size);
size += (uint32_t)sizeof(struct olsr_hmsg_tc);
if (size > DGRAM_MAX_SIZE)
return;
tc->ansn = short_be(my_ansn);
r = olsr_build_tc_neighbors(dgram + size, DGRAM_MAX_SIZE - size, &last_neighbor);
size += r;
msg_tc->size = short_be((uint16_t)(sizeof(struct olsrmsg) + sizeof(struct olsr_hmsg_tc) + r));
olsr_scheduled_output(OLSR_TC_INTERVAL, dgram, (uint16_t)size, pdev );
} while(last_neighbor);
}
static void olsr_compose_hello_dgram(struct pico_device *pdev, struct pico_ipv4_link *ep)
{
struct olsrmsg *msg_hello;
uint32_t size = 0, r;
struct olsr_route_entry *last_neighbor = NULL;
uint8_t *dgram;
struct olsr_hmsg_hello *hello;
/* HELLO Message */
do {
dgram = PICO_ZALLOC(DGRAM_MAX_SIZE);
if (!dgram) {
OOM();
return;
}
size = (uint32_t)sizeof(struct olsrhdr);
msg_hello = (struct olsrmsg *) (dgram + size);
size += (uint32_t)sizeof(struct olsrmsg);
msg_hello->type = OLSRMSG_HELLO;
msg_hello->vtime = seconds2olsr(DEFAULT_VTIME);
msg_hello->orig.addr = ep->address.addr;
msg_hello->ttl = 1;
msg_hello->hop = 0;
msg_hello->seq = short_be(msg_counter++);
hello = (struct olsr_hmsg_hello *)(dgram + size);
size += (uint32_t)sizeof(struct olsr_hmsg_hello);
hello->reserved = 0;
hello->htime = seconds2olsr(OLSR_HELLO_INTERVAL);
hello->htime = 0x05; /* Todo: find and define values */
hello->willingness = 0x07;
if (DGRAM_MAX_SIZE > size) {
r = olsr_build_hello_neighbors(dgram + size, DGRAM_MAX_SIZE - size, &last_neighbor);
if (r == 0) {
/* olsr_dbg("Building hello message\n"); */
PICO_FREE(dgram);
return;
}
}
size += r;
msg_hello->size = short_be((uint16_t)(sizeof(struct olsrmsg) + sizeof(struct olsr_hmsg_hello) + r));
olsr_scheduled_output(OLSR_HELLO_INTERVAL, dgram, (uint16_t)size, pdev );
} while(last_neighbor);
}
static void olsr_make_dgram(struct pico_device *pdev, int full)
{
struct pico_ipv4_link *ep;
ep = pico_ipv4_link_by_dev(pdev);
if (!ep) {
return;
}
if (!full) {
olsr_compose_hello_dgram(pdev, ep);
} else {
olsr_compose_tc_dgram(pdev, ep);
} /*if full */
}
/* Old code was relying on ethernet arp requests */
#define arp_storm(...) do {} while(0)
static void recv_mid(uint8_t *buffer, uint32_t len, struct olsr_route_entry *origin)
{
uint32_t parsed = 0;
uint32_t *address;
struct olsr_route_entry *e;
if (len % sizeof(uint32_t)) /*drop*/
return;
while (len > parsed) {
address = (uint32_t *)(buffer + parsed);
e = get_route_by_address(Local_interfaces, *address);
if (!e) {
e = PICO_ZALLOC(sizeof(struct olsr_route_entry));
if (!e) {
olsr_dbg("olsr allocating route\n");
OOM();
return;
}
e->time_left = (OLSR_HELLO_INTERVAL << 2);
e->destination.addr = *address;
e->gateway = origin;
/* e->iface = origin->iface; */
e->iface = NULL;
e->metric = (uint16_t)(origin->metric + 1u);
e->lq = origin->lq;
e->nlq = origin->nlq;
olsr_route_add(e);
arp_storm(&e->destination);
} else if (e->metric > (origin->metric + 1)) {
olsr_route_del(e);
e->metric = (uint16_t)(origin->metric + 1u);
e->gateway = origin;
e->time_left = (OLSR_HELLO_INTERVAL << 2);
olsr_route_add(e);
}
parsed += (uint32_t)sizeof(uint32_t);
}
}
/* static void recv_hello(uint8_t *buffer, uint32_t len, struct olsr_route_entry *origin) */
static void recv_hello(uint8_t *buffer, uint32_t len, struct olsr_route_entry *origin, uint16_t hops)
{
struct olsr_link *li;
struct olsr_route_entry *e;
uint32_t parsed = 0;
struct olsr_neighbor *neigh;
if (!origin)
return;
/* Don't parse hello messages that were forwarded */
if (hops > 0 || origin->metric > 1)
return;
if (pico_ipv4_link_get(&origin->destination))
return;
while (len > parsed) {
li = (struct olsr_link *) buffer;
neigh = (struct olsr_neighbor *)(buffer + parsed + sizeof(struct olsr_link));
parsed += short_be(li->link_msg_size);
e = get_route_by_address(Local_interfaces, neigh->addr);
if (!e) {
e = PICO_ZALLOC(sizeof(struct olsr_route_entry));
if (!e) {
olsr_dbg("olsr allocating route\n");
OOM();
return;
}
e->time_left = (OLSR_HELLO_INTERVAL << 2);
e->destination.addr = neigh->addr;
e->gateway = origin;
e->iface = NULL;
e->metric = (uint16_t)(origin->metric + hops + 1);
e->link_type = OLSRLINK_UNKNOWN;
e->lq = MIN(origin->lq, neigh->lq);
e->nlq = MIN(origin->nlq, neigh->nlq);
olsr_route_add(e);
arp_storm(&e->destination);
} else if ((e->gateway != origin) && (origin->metric > 1) && (e->metric > (origin->metric + hops + 1))) {
olsr_route_del(e);
e->metric = (uint16_t)(origin->metric + hops + 1);
e->gateway = origin;
e->time_left = (OLSR_HELLO_INTERVAL << 2);
olsr_route_add(e);
} else {
e->time_left = (OLSR_HELLO_INTERVAL << 2);
}
}
}
/* static uint32_t reconsider_topology(uint8_t *buf, uint32_t size, struct olsr_route_entry *e) */
static uint32_t reconsider_topology(uint8_t *buf, uint32_t size, struct olsr_route_entry *e)
{
struct olsr_hmsg_tc *tc = (struct olsr_hmsg_tc *) buf;
uint16_t new_ansn = short_be(tc->ansn);
uint32_t parsed = sizeof(struct olsr_hmsg_tc);
struct olsr_route_entry *rt;
struct olsr_neighbor *n;
uint32_t retval = 0;
if (!e->advertised_tc)
retval = 1;
if (e->advertised_tc && fresher(new_ansn, e->ansn))
{
PICO_FREE(e->advertised_tc); /* <--- XXX check invalid free? */
e->advertised_tc = NULL;
retval = 1;
}
/* Ignore self packets */
if (pico_ipv4_link_get(&e->destination))
return 0;
if (!e->advertised_tc) {
e->advertised_tc = PICO_ZALLOC(size);
if (!e->advertised_tc) {
OOM();
olsr_dbg("Allocating forward packet\n");
return 0;
}
memcpy(e->advertised_tc, buf, size);
e->ansn = new_ansn;
while (parsed < size) {
n = (struct olsr_neighbor *) (buf + parsed);
parsed += (uint32_t)sizeof(struct olsr_neighbor);
rt = get_route_by_address(Local_interfaces, n->addr);
if (rt && (rt->gateway == e)) {
/* Refresh existing node */
rt->time_left = e->time_left;
} else if (!rt || (rt->metric > (e->metric + 1)) || (rt->nlq < n->nlq)) {
if (!rt) {
rt = PICO_ZALLOC(sizeof (struct olsr_route_entry));
if (!rt) {
OOM();
return retval;
}
rt->destination.addr = n->addr;
rt->link_type = OLSRLINK_UNKNOWN;
} else {
olsr_route_del(rt);
}
rt->iface = e->iface;
rt->gateway = e;
rt->metric = (uint16_t)(e->metric + 1);
rt->lq = n->lq; /* 0xff */
rt->nlq = n->nlq; /* 0xff */
rt->time_left = e->time_left; /* 256 */
olsr_route_add(rt);
}
}
/* olsr_dbg("Routes changed...\n"); */
}
return retval;
}
static void olsr_recv(uint8_t *buffer, uint32_t len)
{
struct olsrmsg *msg;
struct olsrhdr *oh = (struct olsrhdr *) buffer;
struct olsr_route_entry *ancestor;
uint32_t parsed = 0;
uint16_t outsize = 0;
uint8_t *datagram;
if (len != short_be(oh->len)) {
return;
}
/* RFC 3626, section 3.4, if a packet is too small, it is silently discarded */
if (len < 16) {
return;
}
parsed += (uint32_t)sizeof(struct olsrhdr);
datagram = PICO_ZALLOC(DGRAM_MAX_SIZE);
if (!datagram) {
OOM();
return;
}
outsize = (uint16_t) (outsize + (sizeof(struct olsrhdr)));
/* Section 1: parsing received messages. */
while (len > parsed) {
struct olsr_route_entry *origin;
msg = (struct olsrmsg *) (buffer + parsed);
origin = get_route_by_address(Local_interfaces, msg->orig.addr);
if(pico_ipv4_link_find(&msg->orig) != NULL) {
/* olsr_dbg("rebound\n"); */
parsed += short_be(msg->size);
continue;
}
/* OLSR's TTL expired. */
if (msg->ttl < 1u) {
parsed += short_be(msg->size);
continue;
}
if (!origin) {
if (msg->hop == 0) {
struct olsr_route_entry *e = PICO_ZALLOC(sizeof (struct olsr_route_entry));
if (!e) {
parsed += short_be(msg->size);
OOM();
break;
}
e->destination.addr = msg->orig.addr;
e->link_type = OLSRLINK_SYMMETRIC;
e->time_left = (OLSR_HELLO_INTERVAL << 2);
e->iface = Local_devices->dev;
e->gateway = olsr_get_ethentry(e->iface);
e->metric = 1;
e->lq = 0xFF;
e->nlq = 0xFF;
olsr_route_add(e);
}
parsed += short_be(msg->size);
continue;
}
/* We know this is a Master host and a neighbor */
origin->link_type = OLSRLINK_MPR;
origin->time_left = olsr2seconds(msg->vtime);
switch(msg->type) {
case OLSRMSG_HELLO:
ancestor = olsr_get_ethentry(origin->iface);
if ((origin->metric > 1) && ancestor) {
olsr_route_del(origin);
origin->gateway = ancestor;
origin->metric = 1;
olsr_route_add(origin);
}
recv_hello(buffer + (uint32_t)parsed + (uint32_t)sizeof(struct olsrmsg) + (uint32_t)sizeof(struct olsr_hmsg_hello),
(uint32_t) ((short_be(msg->size) - (sizeof(struct olsrmsg))) - (uint32_t)sizeof(struct olsr_hmsg_hello)),
origin, msg->hop);
msg->ttl = 0;
break;
case OLSRMSG_MID:
if ((origin->seq != 0) && (!fresher(short_be(msg->seq), origin->seq))) {
msg->ttl = 0;
} else {
recv_mid(buffer + parsed + sizeof(struct olsrmsg), (uint32_t)(short_be(msg->size) - (sizeof(struct olsrmsg))), origin);
/* olsr_dbg("MID forwarded from origin %08x (seq: %u)\n", long_be(msg->orig.addr), short_be(msg->seq)); */
origin->seq = short_be(msg->seq);
}
break;
case OLSRMSG_TC:
if(!pico_ipv4_link_find(&origin->destination)) {
reconsider_topology(buffer + parsed + sizeof(struct olsrmsg), (uint32_t)(short_be(msg->size) - (sizeof(struct olsrmsg))), origin);
if ((origin->seq != 0) && (!fresher(short_be(msg->seq), origin->seq))) {
msg->ttl = 0;
} else {
/* olsr_dbg("TC forwarded from origin %08x (seq: %u)\n", long_be(msg->orig.addr), short_be(msg->seq)); */
origin->seq = short_be(msg->seq);
}
}
break;
default:
PICO_FREE(datagram);
return;
}
if (msg->ttl > 1) {
msg->hop++;
msg->ttl--;
memcpy(datagram + outsize, msg, short_be(msg->size));
outsize = (uint16_t)(outsize + short_be(msg->size));
}
parsed += short_be(msg->size);
}
/* Section 2: forwarding parsed messages that got past the filter. */
if ((outsize > sizeof(struct olsrhdr))) {
/* Finalize FWD packet */
olsr_scheduled_output(OLSR_MAXJITTER, datagram, outsize, NULL);
} else {
/* Nothing to forward. */
PICO_FREE(datagram);
}
}
static void wakeup(uint16_t ev, struct pico_socket *s)
{
unsigned char *recvbuf;
int r = 0;
struct pico_ip4 ANY = {
0
};
uint16_t port = OLSR_PORT;
recvbuf = PICO_ZALLOC(DGRAM_MAX_SIZE);
if (!recvbuf) {
OOM();
return;
}
if (ev & PICO_SOCK_EV_RD) {
r = pico_socket_recv(s, recvbuf, DGRAM_MAX_SIZE);
if (r > 0)
olsr_recv(recvbuf, (uint32_t)r);
}
if (ev == PICO_SOCK_EV_ERR) {
pico_socket_close(udpsock);
udpsock = pico_socket_open(PICO_PROTO_IPV4, PICO_PROTO_UDP, &wakeup);
if (udpsock)
pico_socket_bind(udpsock, &ANY, &port);
}
PICO_FREE(recvbuf);
}
static void olsr_hello_tick(pico_time when, void *unused)
{
struct olsr_dev_entry *d;
(void)when;
(void)unused;
olsr_garbage_collector(Local_interfaces);
refresh_routes();
d = Local_devices;
while(d) {
olsr_make_dgram(d->dev, 0);
d = d->next;
}
if (!pico_timer_add(OLSR_HELLO_INTERVAL, &olsr_hello_tick, NULL)) {
olsr_dbg("OLSR: Failed to start hello_tick timer\n");
/* TODO no more ticks now */
}
}
static void olsr_tc_tick(pico_time when, void *unused)
{
struct olsr_dev_entry *d;
(void)when;
(void)unused;
d = Local_devices;
while(d) {
olsr_make_dgram(d->dev, 1);
d = d->next;
}
if (!pico_timer_add(OLSR_TC_INTERVAL, &olsr_tc_tick, NULL)) {
olsr_dbg("OLSR: Failed to start tc_tick timer\n");
/* TODO no more ticks now */
}
}
/* Public interface */
void pico_olsr_init(void)
{
uint32_t hello_timer = 0;
struct pico_ip4 ANY = {
0
};
uint16_t port = OLSR_PORT;
olsr_dbg("OLSR initialized.\n");
if (!udpsock) {
udpsock = pico_socket_open(PICO_PROTO_IPV4, PICO_PROTO_UDP, &wakeup);
if (udpsock)
pico_socket_bind(udpsock, &ANY, &port);
}
hello_timer = pico_timer_add(pico_rand() % 100, &olsr_hello_tick, NULL);
if (!hello_timer) {
olsr_dbg("OLSR: Failed to start hello_tick timer\n");
return;
}
if (!pico_timer_add(pico_rand() % 900, &olsr_tc_tick, NULL)) {
olsr_dbg("OLSR: Failed to start tc_tick timer\n");
pico_timer_cancel(hello_timer);
}
}
int OOM(void)
{
volatile int c = 3600;
c++;
c++;
c++;
return -1;
}
int pico_olsr_add(struct pico_device *dev)
{
struct pico_ipv4_link *lnk = NULL;
struct olsr_dev_entry *od;
if (!dev) {
pico_err = PICO_ERR_EINVAL;
return -1;
}
/* olsr_dbg("OLSR: Adding device %s\n", dev->name); */
od = PICO_ZALLOC(sizeof(struct olsr_dev_entry));
if (!od) {
pico_err = PICO_ERR_ENOMEM;
/* OOM(); */
return -1;
}
od->dev = dev;
od->next = Local_devices;
Local_devices = od;
do {
char ipaddr[20];
lnk = pico_ipv4_link_by_dev_next(dev, lnk);
if (lnk) {
struct olsr_route_entry *e = PICO_ZALLOC(sizeof(struct olsr_route_entry));
/* olsr_dbg("OLSR: Found IP address %08x\n", long_be(lnk->address.addr)); */
pico_ipv4_to_string(ipaddr, (lnk->address.addr));
/* olsr_dbg("OLSR: Found IP address %s\n", ipaddr); */
if (!e) {
olsr_dbg("olsr allocating route\n");
pico_err = PICO_ERR_ENOMEM;
return -1;
}
e->destination.addr = lnk->address.addr;
e->link_type = OLSRLINK_SYMMETRIC;
e->time_left = (OLSR_HELLO_INTERVAL << 2);
e->gateway = NULL;
e->children = NULL;
e->iface = dev;
e->metric = 0;
e->lq = 0xFF;
e->nlq = 0xFF;
e->next = Local_interfaces;
Local_interfaces = e;
}
} while(lnk);
return 0;
}
#endif
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