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#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include "ppp.h"
#include "ppp_lcp.h"
#include "log.h"
static struct lcp_option_t *magic_init(struct ppp_lcp_t *lcp);
static void magic_free(struct ppp_lcp_t *lcp, struct lcp_option_t *opt);
static int magic_send_conf_req(struct ppp_lcp_t *lcp, struct lcp_option_t *opt, uint8_t *ptr);
static int magic_recv_conf_req(struct ppp_lcp_t *lcp, struct lcp_option_t *opt, uint8_t *ptr);
static void magic_print(void (*print)(const char *fmt,...),struct lcp_option_t*, uint8_t *ptr);
struct magic_option_t
{
struct lcp_option_t opt;
int magic;
};
static struct lcp_option_handler_t magic_opt_hnd=
{
.init=magic_init,
.send_conf_req=magic_send_conf_req,
.recv_conf_req=magic_recv_conf_req,
.free=magic_free,
.print=magic_print,
};
static struct lcp_option_t *magic_init(struct ppp_lcp_t *lcp)
{
struct magic_option_t *magic_opt=malloc(sizeof(*magic_opt));
memset(magic_opt,0,sizeof(*magic_opt));
magic_opt->magic=random();
magic_opt->opt.id=CI_MAGIC;
magic_opt->opt.len=6;
lcp->magic = magic_opt->magic;
return &magic_opt->opt;
}
static void magic_free(struct ppp_lcp_t *lcp, struct lcp_option_t *opt)
{
struct magic_option_t *magic_opt=container_of(opt,typeof(*magic_opt),opt);
free(magic_opt);
}
static int magic_send_conf_req(struct ppp_lcp_t *lcp, struct lcp_option_t *opt, uint8_t *ptr)
{
struct magic_option_t *magic_opt=container_of(opt,typeof(*magic_opt),opt);
struct lcp_opt32_t *opt32=(struct lcp_opt32_t*)ptr;
opt32->hdr.id=CI_MAGIC;
opt32->hdr.len=6;
opt32->val=htonl(magic_opt->magic);
return 6;
}
static int magic_recv_conf_req(struct ppp_lcp_t *lcp, struct lcp_option_t *opt, uint8_t *ptr)
{
struct magic_option_t *magic_opt=container_of(opt,typeof(*magic_opt),opt);
struct lcp_opt32_t *opt32=(struct lcp_opt32_t*)ptr;
if (magic_opt->magic==ntohl(opt32->val))
{
log_error("loop detected");
return -1;
}
return LCP_OPT_ACK;
}
static void magic_print(void (*print)(const char *fmt,...),struct lcp_option_t *opt, uint8_t *ptr)
{
struct magic_option_t *magic_opt=container_of(opt,typeof(*magic_opt),opt);
print("<magic %04x>",magic_opt->magic);
}
static void __init magic_opt_init()
{
lcp_option_register(&magic_opt_hnd);
}
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