zapret/tpws/hostlist.c

#include <stdio.h>
#include "hostlist.h"
#include "gzip.h"
#include "params.h"
#include "helpers.h"

// inplace tolower() and add to pool
static bool addpool(strpool **hostlist, char **s, const char *end)
{
	char *p;

	// advance until eol lowering all chars
	for (p = *s; p < end && *p && *p != '\r' && *p != '\n'; p++)
		*p = tolower(*p);
	if (!StrPoolAddStrLen(hostlist, *s, p - *s))
	{
		StrPoolDestroy(hostlist);
		*hostlist = NULL;
		return false;
	}
	// advance to the next line
	for (; p < end && (!*p || *p == '\r' || *p == '\n'); p++)
		;
	*s = p;
	return true;
}

bool AppendHostList(strpool **hostlist, char *filename)
{
	char *p, *e, s[256], *zbuf;
	size_t zsize;
	int ct = 0;
	FILE *F;
	int r;

	DLOG_CONDUP("Loading hostlist %s\n", filename);

	if (!(F = fopen(filename, "rb")))
	{
		DLOG_ERR("Could not open %s\n", filename);
		return false;
	}

	if (is_gzip(F))
	{
		r = z_readfile(F, &zbuf, &zsize);
		fclose(F);
		if (r == Z_OK)
		{
			DLOG_CONDUP("zlib compression detected. uncompressed size : %zu\n", zsize);

			p = zbuf;
			e = zbuf + zsize;
			while (p < e)
			{
				if (*p == '#' || *p == ';' || *p == '/' || *p == '\n')
					continue;
				if (!addpool(hostlist, &p, e))
				{
					DLOG_ERR("Not enough memory to store host list : %s\n", filename);
					free(zbuf);
					return false;
				}
				ct++;
			}
			free(zbuf);
		}
		else
		{
			DLOG_ERR("zlib decompression failed : result %d\n", r);
			return false;
		}
	}
	else
	{
		DLOG_CONDUP("loading plain text list\n");

		while (fgets(s, 256, F))
		{
			p = s;
			if (*p == '#' || *p == ';' || *p == '/' || *p == '\n')
				continue;
			if (!addpool(hostlist, &p, p + strlen(p)))
			{
				DLOG_ERR("Not enough memory to store host list : %s\n", filename);
				fclose(F);
				return false;
			}
			ct++;
		}
		fclose(F);
	}

	DLOG_CONDUP("Loaded %d hosts from %s\n", ct, filename);
	return true;
}

bool LoadHostLists(strpool **hostlist, struct str_list_head *file_list)
{
	struct str_list *file;

	if (*hostlist)
	{
		StrPoolDestroy(hostlist);
		*hostlist = NULL;
	}

	LIST_FOREACH(file, file_list, next)
	{
		if (!AppendHostList(hostlist, file->str))
			return false;
	}
	return true;
}

bool NonEmptyHostlist(strpool **hostlist)
{
	// add impossible hostname if the list is empty
	return *hostlist ? true : StrPoolAddStrLen(hostlist, "@&()", 4);
}

bool SearchHostList(strpool *hostlist, const char *host)
{
	if (hostlist)
	{
		const char *p = host;
		bool bInHostList;
		while (p)
		{
			bInHostList = StrPoolCheckStr(hostlist, p);
			VPRINT("Hostlist check for %s : %s\n", p, bInHostList ? "positive" : "negative");
			if (bInHostList)
				return true;
			p = strchr(p, '.');
			if (p)
				p++;
		}
	}
	return false;
}

// return : true = apply fooling, false = do not apply
static bool HostlistCheck_(strpool *hostlist, strpool *hostlist_exclude, const char *host, bool *excluded)
{
	if (excluded)
		*excluded = false;
	if (hostlist_exclude)
	{
		VPRINT("Checking exclude hostlist\n");
		if (SearchHostList(hostlist_exclude, host))
		{
			if (excluded)
				*excluded = true;
			return false;
		}
	}
	if (hostlist)
	{
		VPRINT("Checking include hostlist\n");
		return SearchHostList(hostlist, host);
	}
	return true;
}

// return : true = apply fooling, false = do not apply
bool HostlistCheck(const char *host, bool *excluded)
{
	if (*params.hostlist_auto_filename)
	{
		time_t t = file_mod_time(params.hostlist_auto_filename);
		if (t != params.hostlist_auto_mod_time)
		{
			DLOG_CONDUP("Autohostlist was modified by another process. Reloading include hostslist.\n");
			if (!LoadIncludeHostLists())
			{
				// what will we do without hostlist ?? sure, gonna die
				exit(1);
			}
			params.hostlist_auto_mod_time = t;
		}
	}
	return HostlistCheck_(params.hostlist, params.hostlist_exclude, host, excluded);
}

bool LoadIncludeHostLists()
{
	if (!LoadHostLists(&params.hostlist, &params.hostlist_files))
		return false;
	if (*params.hostlist_auto_filename)
		params.hostlist_auto_mod_time = file_mod_time(params.hostlist_auto_filename);
	return true;
}
bool LoadExcludeHostLists()
{
	return LoadHostLists(&params.hostlist_exclude, &params.hostlist_exclude_files);
}