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#include <stdlib.h>
#include <string.h>
#include <bglibs/iobuf.h>
#include <bglibs/msg.h>
#include <bglibs/wrap.h>
#include <bglibs/str.h>
#include "mailfront.h"
struct pattern
{
int mode;
str s;
const char* message;
};
#define T_AFTER_BLANK ('\\')
#define T_RESPONSE ('=')
#define T_COMMENT ('#')
#define T_HEADER (':')
#define T_NORMAL (0)
static response resp_patmatch = { 554, 0 };
static struct pattern* pattern_list;
static str responses;
static unsigned pattern_count;
static int linemode;
static unsigned linepos;
static unsigned linemax = 256;
static char* linebuf;
static int patterns_read(const char* filename)
{
ibuf in;
int mode;
unsigned i;
unsigned count;
str line = {0,0,0};
const char* currmsg = "This message contains prohibited content";
if (!ibuf_open(&in, filename, 0)) return 0;
count = 0;
/* Count the number of non-comment lines. */
while (ibuf_getstr(&in, &line, LF)) {
str_rstrip(&line);
if (line.len > 0 && line.s[0] != T_COMMENT) {
if (line.s[0] == T_RESPONSE)
/* Pre-allocate room for the responses */
wrap_str(str_catb(&responses, line.s+1, line.len));
else
++count;
}
}
responses.len = 0;
/* Allocate the lines. */
if ((pattern_list = malloc(count * sizeof *pattern_list)) == 0)
die_oom(111);
if (!ibuf_rewind(&in))
die1sys(111, "Could not rewind patterns file");
memset(pattern_list, 0, count * sizeof *pattern_list);
for (i = 0; i < count && ibuf_getstr(&in, &line, LF); ) {
str_rstrip(&line);
if (line.len > 0) {
switch (mode = line.s[0]) {
case T_COMMENT:
continue;
case T_RESPONSE:
currmsg = responses.s + responses.len;
str_catb(&responses, line.s+1, line.len);
continue;
case T_AFTER_BLANK:
case T_HEADER:
break;
default:
mode = T_NORMAL;
}
pattern_list[i].mode = mode;
wrap_str(str_copyb(&pattern_list[i].s, line.s+1, line.len-1));
pattern_list[i].message = currmsg;
++i;
}
}
pattern_count = i;
ibuf_close(&in);
str_free(&line);
return 1;
}
static const response* init(int fd)
{
const char* tmp;
unsigned u;
if ((tmp = session_getenv("PATTERNS")) != 0)
if (!patterns_read(tmp))
warn3sys("Could not read patterns file '", tmp, "'");
if ((tmp = session_getenv("PATTERNS_LINEMAX")) != 0)
if ((u = strtoul(tmp, (char**)&tmp, 10)) > 0 && *tmp == 0)
linemax = u;
if ((linebuf = malloc(linemax+1)) == 0)
die_oom(111);
linemode = T_HEADER;
linepos = 0;
return 0;
(void)fd;
}
static const response* check_line(void)
{
unsigned i;
struct pattern* p;
const str fakeline = { linebuf, linepos, 0 };
linebuf[linepos] = 0;
for (p = pattern_list, i = 0; i < pattern_count; ++i, ++p) {
if ((p->mode == T_NORMAL
|| p->mode == linemode)
&& str_glob(&fakeline, &p->s)) {
resp_patmatch.message = p->message;
return &resp_patmatch;
}
}
return 0;
}
static const response* check(const char* bytes, unsigned long len)
{
const char* p;
const char* const end = bytes + len;
const response* r;
if (linebuf == 0) return 0;
for (p = bytes; p < end; ++p) {
const char ch = *p;
if (ch == LF) {
if (linepos > 0) {
if ((r = check_line()) != 0)
return r;
if (linemode != T_HEADER)
linemode = T_NORMAL;
}
else
linemode = T_AFTER_BLANK;
linepos = 0;
}
else {
if (linepos < linemax)
linebuf[linepos++] = ch;
}
}
return 0;
}
struct plugin plugin = {
.version = PLUGIN_VERSION,
.data_start = init,
.data_block = check,
};
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