headermatch/sme7/headermatch.c

/********
 headermatch checks an rfc822 message on standard input for a matching
 header, and exits 0 if finds a match, and 1 otherwise.

 The header to match by default is "X-Spam-Flag: YES".
 If a command line argument is given, its text is used
 as the sorting header rather than "X-Spam-Flag: YES".
 
 Note that standard input must be able to be mmaped(*) for the testing to
 succeed - this will be the case when qmail-local is doing the delivery.
 If mmap fails then headermatch exits with status 100.
 
 (*) mmap was used so that there are no local buffers used in the program, so
 that the program logic is very simple.

    Copyright (C) 2006 Charlie Brady

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 ***********/

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <unistd.h>
#include <errno.h>

error(const char* s)
{
    write(2, s, strlen(s));
    write(2, "\n", 1);
}

char * find_str(const char* s, const long len, const char* pattern)
{
    char* sptr;
    size_t plen;
    long slen;
    char p;
    if (*pattern == 0) return 0;
    slen = len;
    plen = strlen(pattern);
    for (sptr = (char *)s; (p = *pattern) != 0; ++sptr, --slen)
    {
        if (*sptr == '\n')
        {
            sptr++;
            slen--;
            if (*sptr == '\n')
            {
                return 0;
            }
            if (slen < plen)
            {
                return 0;
            }
            if (!memcmp(sptr, pattern, (size_t)plen))
            {
                return sptr;
            }
        }
    }
    return 0;
}

int main(int argc, char **argv)
{
    struct stat st;
    char *message;
    int fstat_ret;
    char *end_of_headers;
    char *spam_header = "X-Spam-Flag: YES";
    size_t spam_header_len;
    size_t message_len;

    if (argc > 1)
    {
        spam_header = argv[1];
    }
    if (fstat_ret = fstat(0,&st))
    {
        error("Could not fstat standard input");
        exit(111);
    }
    message_len = st.st_size;
    spam_header_len = strlen(spam_header);
    if (message_len < spam_header_len)
    {
        exit(99);
    }
    if (message_len > 0xffffffff)
    {
        error("Input file too big");
        exit(100);
    }
    message = mmap(0,message_len,PROT_READ,MAP_SHARED,0,0);
    if (message + 1)
    {
        if (!memcmp(message, spam_header, spam_header_len))
        {
            munmap(message, message_len);
            exit(0);
        }
        if (find_str(message, message_len, spam_header))
        {
            munmap(message, message_len);
            exit(0);
        }
        munmap(message, message_len);
        exit(99);
    }
    error("MMap failed");
    exit(100);
}
1	slords	1.1	/********
2			headermatch checks an rfc822 message on standard input for a matching
3			header, and exits 0 if finds a match, and 1 otherwise.
4
5			The header to match by default is "X-Spam-Flag: YES".
6			If a command line argument is given, its text is used
7			as the sorting header rather than "X-Spam-Flag: YES".
8
9			Note that standard input must be able to be mmaped(*) for the testing to
10			succeed - this will be the case when qmail-local is doing the delivery.
11			If mmap fails then headermatch exits with status 100.
12
13			(*) mmap was used so that there are no local buffers used in the program, so
14			that the program logic is very simple.
15
16			Copyright (C) 2006 Charlie Brady
17
18			This program is free software; you can redistribute it and/or modify
19			it under the terms of the GNU General Public License as published by
20			the Free Software Foundation; either version 2 of the License, or
21			(at your option) any later version.
22
23			This program is distributed in the hope that it will be useful,
24			but WITHOUT ANY WARRANTY; without even the implied warranty of
25			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26			GNU General Public License for more details.
27
28			You should have received a copy of the GNU General Public License
29			along with this program; if not, write to the Free Software
30			Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
31
32			***********/
33
34			#include <sys/types.h>
35			#include <sys/stat.h>
36			#include <sys/mman.h>
37			#include <unistd.h>
38			#include <errno.h>
39
40			error(const char* s)
41			{
42			write(2, s, strlen(s));
43			write(2, "\n", 1);
44			}
45
46			char * find_str(const char* s, const long len, const char* pattern)
47			{
48			char* sptr;
49			size_t plen;
50			long slen;
51			char p;
52			if (*pattern == 0) return 0;
53			slen = len;
54			plen = strlen(pattern);
55			for (sptr = (char )s; (p = pattern) != 0; ++sptr, --slen)
56			{
57			if (*sptr == '\n')
58			{
59			sptr++;
60			slen--;
61			if (*sptr == '\n')
62			{
63			return 0;
64			}
65			if (slen < plen)
66			{
67			return 0;
68			}
69			if (!memcmp(sptr, pattern, (size_t)plen))
70			{
71			return sptr;
72			}
73			}
74			}
75			return 0;
76			}
77
78			int main(int argc, char **argv)
79			{
80			struct stat st;
81			char *message;
82			int fstat_ret;
83			char *end_of_headers;
84			char *spam_header = "X-Spam-Flag: YES";
85			size_t spam_header_len;
86			size_t message_len;
87
88			if (argc > 1)
89			{
90			spam_header = argv[1];
91			}
92			if (fstat_ret = fstat(0,&st))
93			{
94			error("Could not fstat standard input");
95			exit(111);
96			}
97			message_len = st.st_size;
98			spam_header_len = strlen(spam_header);
99			if (message_len < spam_header_len)
100			{
101			exit(99);
102			}
103			if (message_len > 0xffffffff)
104			{
105			error("Input file too big");
106			exit(100);
107			}
108			message = mmap(0,message_len,PROT_READ,MAP_SHARED,0,0);
109			if (message + 1)
110			{
111			if (!memcmp(message, spam_header, spam_header_len))
112			{
113			munmap(message, message_len);
114			exit(0);
115			}
116			if (find_str(message, message_len, spam_header))
117			{
118			munmap(message, message_len);
119			exit(0);
120			}
121			munmap(message, message_len);
122			exit(99);
123			}
124			error("MMap failed");
125			exit(100);
126			}