session_id = cgi_val(entries,"session_id");
/**
* open session file
*/
strcpy(sfp,"/tmp");
strcat(sfp,"/sess_");
strcat(sfp,session_id);
sf = fopen(sfp,"rb+");
if( sf == NULL )
/** can’t open session file,maybe session has time out **/
{
print_session_error("1");
exit(1);
}
/**
* read session var
*/
bzero(buffer,256);
fread(buffer,1,256,sf);
for(i=0,j=0,k=0;k<5 && i<strlen(buffer);i++)
{
if( buffer[i] == ’\n’ )
{
temp[j] = ’\0’;
strcpy(str_array[k],temp);
j = 0;
k ++;
}
else
{
temp[j++] = buffer[i];
}
}
/**
* check active time
*/
time(&now);
if( now - atoi(str_time) > atoi(parse_config_file("session_live_time")) )
{
print_session_error("2");
exit(1);
}
/**
* compare client hash_key to session hash_key
*/
if( HTTP_COOKIE == "" || strcmp( HTTP_COOKIE+9 , str_hash_key ) != 0 )
{
print_session_error("3");
exit(1);
}
/**
* compare client ip to session ip
*/
if( strcmp( REMOTE_ADDR, str_client_ip ) != 0 )
{
print_session_error("4");
exit(1);
}
/**
* refresh session active time
*/
time(&now);
sprintf(str_time,"%10d\n",now);
fseek(sf,0,SEEK_SET);
fputs(str_time,sf);
/**
* get new hash_key
*/
srand(now);
r = rand();
for(i=0;i<16;i++)
{
srand(r);
r = rand();
str_hash_key[i] = r % 26 + ’a’;
}
str_hash_key[16] = ’\n’;
str_hash_key[17] = ’\0’;
/**
* refresh session hash_key
*/
fseek(sf,11,SEEK_SET);
fputs(str_hash_key,sf);
fclose(sf);
/**
* send cookie refresh client hash_key
*/
printf("Set-Cookie:hash_key=%s",str_hash_key);
}
void kill_session()
{
char *session_id;
char *session_path;
char sfp[128];
session_id = cgi_val(entries,"session_id");
strcpy(sfp,"/tmp");
strcat(sfp,"/sess_");
strcat(sfp,session_id);
remove(sfp);
}
void clean_session_file()
{
DIR *pdir;
struct dirent *ent;
char *path;
char *filename;
char filepath[64];
int fd;
char str_time[11];
time_t now;
path = "/tmp";
pdir = opendir(path);
if(pdir != NULL)
{
while( ent =readdir(pdir) )
{
filename = ent->d_name;
if( strncmp(filename,"sess_",5)==0 )
{
strcpy(filepath,path);
strcat(filepath,"/");
strcat(filepath,filename);
fd = open(filepath,O_RDONLY);
read(fd,str_time,10);
time(&now);
if( now - atoi(str_time) > atoi(parse_config_file("session_live_time")) )
{
remove(filepath);
}
close(fd);
}
}
}
closedir(pdir);
}
void print_session_error(char *n)
{
printf("Content-type:text/html\n\n");
printf("<html><head>";
print_title("请重新登陆!");
printf("</head>\n");
printf("<body>\n");
printf("对不起，请重新登陆。<p>\n");
printf("你长时间没有操作，登陆已经超时。或者是系统发生了错误。<p>\n");
printf("如果是后者，请与管理人员联系。\n");
printf("<!--%s-->",n);
printf("</body>");
printf("</html>\n");
}