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#include "log.h"
#include "ppp.h"
#include "ppp_auth.h"
#define MSG_FAILED "Authentication failed"
#define MSG_SUCCESSED "Authentication successed"
#define HDR_LEN (sizeof(struct pap_hdr_t)-2)
static int lcp_get_conf_req(struct auth_driver_t*, struct ppp_t*, struct lcp_opt32_t*);
static int lcp_recv_conf_req(struct auth_driver_t*, struct ppp_t*, struct lcp_opt32_t*);
static int begin(struct auth_driver_t*, struct ppp_t*);
static int terminate(struct auth_driver_t*, struct ppp_t*);
static void pap_recv(struct ppp_handler_t*h);
struct pap_proto_t
{
struct ppp_handler_t h;
struct ppp_t *ppp;
};
struct pap_hdr_t
{
uint16_t proto;
uint8_t code;
uint8_t id;
uint16_t len;
} __attribute__((packed));
struct pap_ack_t
{
struct pap_hdr_t hdr;
uint8_t msg_len;
char msg[0];
} __attribute__((packed));
static struct auth_driver_t pap=
{
.type=PPP_PAP,
.get_conf_req=lcp_get_conf_req,
.recv_conf_req=lcp_recv_conf_req,
.start=pap_start,
.finish=pap_finish,
};
int plugin_init(void)
{
if (auth_register(&pap))
{
log_error("pap: failed to register driver\n");
return -1;
}
return 0;
}
static int pap_start(struct auth_driver_t *d, struct ppp_t *ppp)
{
struct pap_proto_t *p=malloc(sizeof(*p));
memset(&p,0,sizeof(*p));
p->h.proto=PPP_PAP;
p->h.recv=pap_recv;
p->ppp=ppp;
ppp->auth_pd=p;
ppp_register_handler(p->ppp,p->h);
return 0;
}
static int pap_finish(struct auth_driver_t *d, struct ppp_t *ppp)
{
struct pap_proto_t *p=(struct pap_proto_t*)ppp->auth_pd;
ppp_unregister_handler(p->ppp,p->h);
free(p);
return 0;
}
static int lcp_get_conf_req(struct auth_driver_t *d, struct ppp_t *ppp, struct lcp_opt32_t *opt)
{
return 0;
}
static int lcp_recv_conf_req(struct auth_driver_t *d, struct ppp_t *ppp, struct lcp_opt32_t *opt)
{
return 0;
}
static void pap_send_ack(struct pap_proto_t *p, int id)
{
uint8_t buf[128];
struct pap_ack_t *msg=(struct pap_ack_t*)buf;
msg->hdr.proto=PPP_PAP;
msg->hdr.code=PAP_ACK;
msg->hdr.id=id;
msg->hdr.len=HDR_LEN+1+sizeof(MSG_SUCCESSED);
msg->len=sizeof(MSG_SUCCESSED);
memcpy(msg->msg,MSG_SUCCESSED,sizeof(MSG_SUCCESSED));
ppp_send(p->ppp,msg,msg->hdr.len+2);
}
static void pap_send_nack(struct pap_proto_t *p,int id)
{
uint8_t buf[128];
struct pap_ack_t *msg=(struct pap_ack_t*)buf;
msg->hdr.proto=PPP_PAP;
msg->hdr.code=PAP_NACK;
msg->hdr.id=id;
msg->hdr.len=HDR_LEN+1+sizeof(MSG_FAILED);
msg->len=sizeof(MSG_FAILED);
memcpy(msg->msg,MSG_FAILED,sizeof(MSG_FAILED));
ppp_send(p->ppp,msg,msg->hdr.len+2);
}
static int pap_recv_req(struct pap_proto_t *p,struct pap_hdr_t *hdr)
{
int ret;
char *peer_id;
char *passwd;
int peer_id_len;
int passwd_len;
uint8_t *ptr=(uint8_t*)(hdr+1);
peer_id_len=*(uint8_t*)ptr; ptr++;
if (peer_id_len>htons(hdr->len)-sizeof(*hdr)-1)
{
log_warn("PAP: short packet received\n");
return -1;
}
peer_id=ptr; ptr+=peer_id_len;
passwd_len=*(uint8_t*)ptr; ptr++;
if (passwd_len>htons(hdr->len)-sizeof(*hdr)-2-peer_id_len)
{
log_warn("PAP: short packet received\n");
return -1;
}
peer_id=stdndup(peer_id,peer_id_len);
passwd=stdndup(ptr,passwd_len);
if (pwdb_check(peer_id,passwd))
{
log_warn("PAP: authentication error\n");
pap_send_nack(p,hdr->id);
auth_failed(p->ppp);
ret=-1;
}else
{
pap_send_ack(p,hdr->id);
auth_successed(p->ppp);
ret=0;
}
free(peer_id);
free(passwd);
return ret;
}
static void pap_recv(struct ppp_handler_t *h)
{
struct pap_proto_t *p=container_of(h,typeof(*p),h);
struct pap_hdr_t *hdr=(struct pap_hdr_t *)p->ppp->in_buf;
if (p->ppp->in_buf_size<sizeof(*hdr) || htons(hdr->len)<HDR_LEN || htons(hdr->len)<p->ppp->in_buf_size-2)
{
log_warn("PAP: short packet received\n");
return;
}
if (hdr->code==PAP_REQ) pap_recv_req(p,hdr);
else
{
log_warn("PAP: unknown code received %x\n",hdr->code);
}
}
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