mblaze/mmime.c
2017-01-26 20:27:26 +01:00

389 lines
7.7 KiB
C

#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <pwd.h>
#include <search.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include "blaze822.h"
static int cflag;
static int rflag;
int gen_b64(uint8_t *s, off_t size)
{
static char *b64 =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
off_t i;
int l;
uint32_t v;
for (i = 0, l = 0; i+2 < size; i += 3) {
v = (s[i] << 16) | (s[i+1] << 8) | s[i+2];
putc_unlocked(b64[(v & 0xfc0000) >> 18], stdout);
putc_unlocked(b64[(v & 0x03f000) >> 12], stdout);
putc_unlocked(b64[(v & 0x000fc0) >> 6], stdout);
putc_unlocked(b64[(v & 0x3f)], stdout);
l += 4;
if (l > 72) {
l = 0;
printf("\n");
}
}
if (size - i == 2) { // 2 bytes left, XXX=
v = (s[size - 2] << 16) | (s[size - 1] << 8);
putc_unlocked(b64[(v & 0xfc0000) >> 18], stdout);
putc_unlocked(b64[(v & 0x03f000) >> 12], stdout);
putc_unlocked(b64[(v & 0x000fc0) >> 6], stdout);
putc_unlocked('=', stdout);
} else if (size - i == 1) { // 1 byte left, XX==
v = s[size - 1] << 16;
putc_unlocked(b64[(v & 0xfc0000) >> 18], stdout);
putc_unlocked(b64[(v & 0x03f000) >> 12], stdout);
putc_unlocked('=', stdout);
putc_unlocked('=', stdout);
}
printf("\n");
return 0;
}
int gen_qp(uint8_t *s, off_t size, int maxlinelen, int header)
{
off_t i;
int linelen = 0;
char prev = 0;
for (i = 0; i < size; i++) {
if ((s[i] > 126) ||
(s[i] < 32 && s[i] != '\n' && s[i] != '\t') ||
(s[i] == '=')) {
printf("=%02X", s[i]);
linelen += 3;
prev = s[i];
} else if (header &&
(s[i] == '\n' || s[i] == '\t' || s[i] == '_')) {
printf("=%02X", s[i]);
linelen += 3;
prev = '_';
} else if (header && s[i] == ' ') {
putc_unlocked('_', stdout);
linelen++;
prev = '_';
} else if (s[i] == '\n') {
if (prev == ' ' || prev == '\t')
puts("=");
putc_unlocked('\n', stdout);
linelen = 0;
prev = 0;
} else {
putc_unlocked(s[i], stdout);
linelen++;
prev = s[i];
}
if (linelen >= maxlinelen-3) {
linelen = 0;
prev = '\n';
puts("=");
}
}
if (linelen > 0 && !header)
puts("=");
return linelen;
}
static const char *
basenam(const char *s)
{
char *r = strrchr(s, '/');
return r ? r + 1 : s;
}
int gen_file(char *file, char *ct)
{
uint8_t *content;
off_t size;
int r = slurp(file, (char **)&content, &size);
if (r != 0) {
fprintf(stderr, "mmime: error attaching file '%s': %s",
file, strerror(r));
return -1;
}
off_t bithigh = 0;
off_t bitlow = 0;
off_t linelen = 0;
off_t maxlinelen = 0;
off_t i;
for (i = 0; i < size; i++) {
if (content[i] == '\n') {
if (maxlinelen < linelen)
maxlinelen = linelen;
linelen = 0;
} else {
linelen++;
}
if (content[i] != '\t' && content[i] != '\n' && content[i] < 32)
bitlow++;
if (content[i] > 127)
bithigh++;
}
printf("Content-Disposition: attachment; filename=\"%s\"\n",
basenam(file));
if (bitlow == 0 && bithigh == 0 &&
maxlinelen <= 78 && content[size-1] == '\n') {
if (!ct)
ct = "text/plain";
printf("Content-Type: %s\n", ct);
printf("Content-Transfer-Encoding: 7bit\n\n");
fwrite(content, 1, size, stdout);
return 0;
} else if (bitlow == 0 && bithigh == 0) {
if (!ct)
ct = "text/plain";
printf("Content-Type: %s\n", ct);
printf("Content-Transfer-Encoding: quoted-printable\n\n");
gen_qp(content, size, 78, 0);
return 0;
} else if (bitlow > size/10 || bithigh > size/4) {
if (!ct)
ct = "application/binary";
printf("Content-Type: %s\n", ct);
printf("Content-Transfer-Encoding: base64\n\n");
return gen_b64(content, size);
} else {
if (!ct)
ct = "text/plain";
printf("Content-Type: %s\n", ct);
printf("Content-Transfer-Encoding: quoted-printable\n\n");
gen_qp(content, size, 78, 0);
return 0;
}
}
void
print_header(char *line) {
char *s, *e;
size_t l = strlen(line);
if (line[l-1] == '\n')
line[l-1] = 0;
/* iterate word-wise, encode words when needed. */
s = line;
if (!(*s == ' ' || *s == '\t')) {
// raw header name
while (*s && *s != ':')
putc_unlocked(*s++, stdout);
if (*s == ':')
putc_unlocked(*s++, stdout);
}
int prevq = 0;
int linelen = s - line;
while (*s) {
size_t highbit = 0;
e = s;
while (*e && *e == ' ')
e++;
for (; *e && *e != ' '; e++) {
if ((uint8_t) *e >= 127)
highbit++;
}
// use qp for lines with high bit, for long lines, or
// for more than two spaces
if (highbit ||
e-s > 78-linelen ||
(prevq && s[0] == ' ' && s[1] == ' ')) {
if (!prevq && s[0] == ' ')
s++;
// 13 = strlen(" =?UTF-8?Q??=")
int w;
while (s < e && (w = (78-linelen-13) / (highbit?3:1)) < e-s && w>0) {
printf(" =?UTF-8?Q?");
gen_qp((uint8_t *)s, w>e-s?e-s:w, 999, 1);
printf("?=\n");
s += w;
linelen = 0;
prevq = 1;
}
if (s < e) {
if (linelen + (e-s)+13 > 78) {
printf("\n ");
linelen = 1;
}
if (highbit || s[0] == ' ') {
printf(" =?UTF-8?Q?");
linelen += 14;
linelen += gen_qp((uint8_t *)s, e-s, 999, 1);
printf("?=");
prevq = 1;
} else {
fwrite(s, 1, e-s, stdout);
linelen += e-s;
prevq = 0;
}
}
} else {
if (linelen + (e-s) > 78) {
printf("\n");
if (*s != ' ')
printf(" ");
linelen = 0;
}
fwrite(s, 1, e-s, stdout);
linelen += e-s;
prevq = 0;
}
s = e;
}
printf("\n");
}
int
gen_build()
{
char sep[100];
snprintf(sep, sizeof sep, "----_=_%08lx%08lx%08lx_=_",
lrand48(), lrand48(), lrand48());
char *line = 0;
size_t linelen = 0;
int inheader = 1;
int intext = 0;
while (1) {
int read = getdelim(&line, &linelen, '\n', stdin);
if (read == -1) {
if (feof(stdin))
break;
else
exit(1);
}
if (inheader) {
if (line[0] == '\n') {
inheader = 0;
printf("MIME-Version: 1.0\n");
if (rflag) {
printf("Content-Type: text/plain; charset=UTF-8\n");
printf("Content-Transfer-Encoding: quoted-printable\n\n");
} else {
printf("Content-Type: multipart/mixed; boundary=\"%s\"\n", sep);
printf("\n");
printf("This is a multipart message in MIME format.\n");
}
} else {
print_header(line);
}
continue;
}
if (!rflag && line[0] == '#') {
char *f = strchr(line, ' ');
if (f) {
char of = *f;
*f = 0;
if (strchr(line, '/')) {
printf("\n--%s\n", sep);
if (line[read-1] == '\n')
line[read-1] = 0;
gen_file(f+1, (char *)line+1);
intext = 0;
continue;
}
*f = of;
}
}
if (!rflag && !intext) {
printf("\n--%s\n", sep);
printf("Content-Type: text/plain; charset=UTF-8\n");
printf("Content-Disposition: inline\n");
printf("Content-Transfer-Encoding: quoted-printable\n\n");
intext = 1;
}
gen_qp((uint8_t *)line, strlen(line), 78, 0);
}
if (!rflag && !inheader)
printf("\n--%s--\n", sep);
free(line);
return 0;
}
int
check()
{
off_t bithigh = 0;
off_t bitlow = 0;
off_t linelen = 0;
off_t maxlinelen = 0;
int c;
int l = -1;
while ((c = getchar()) != EOF) {
if (c == '\n') {
if (maxlinelen < linelen)
maxlinelen = linelen;
linelen = 0;
} else {
linelen++;
}
if (c != '\t' && c != '\n' && c < 32)
bitlow++;
if (c > 127)
bithigh++;
l = c;
}
if (bitlow == 0 && bithigh == 0 && maxlinelen <= 78 && l == '\n')
return 0;
else
return 1;
}
int
main(int argc, char *argv[])
{
srand48(time(0) ^ getpid());
int c;
while ((c = getopt(argc, argv, "cr")) != -1)
switch(c) {
case 'r': rflag = 1; break;
case 'c': cflag = 1; break;
default:
usage:
fprintf(stderr, "Usage: mmime [-c|-r] < message\n");
exit(1);
}
if (argc != optind)
goto usage;
if (cflag)
return check();
return gen_build();
}