mblaze/mmime.c
Leah Neukirchen 66d0eff12f style
2017-08-31 17:30:17 +02:00

492 lines
9.7 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;
static char *tflag = "multipart/mixed";
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 linelen)
{
off_t i;
int header = linelen > 0;
char prev = 0;
for (i = 0; i < size; i++) {
// inspect utf8 sequence to not wrap in between multibyte
int mb;
if ((s[i] & 0x80) == 0) mb = 3;
else if ((s[i] & 0xc0) == 0x80) mb = 3;
else if ((s[i] & 0xe0) == 0xc0) mb = 6;
else if ((s[i] & 0xf0) == 0xe0) mb = 9;
else if ((s[i] & 0xf8) == 0xf0) mb = 12;
else mb = 3;
if (linelen >= maxlinelen-mb-!!header) {
linelen = 0;
prev = '\n';
if (header) {
printf("?=\n =?UTF-8?Q?");
linelen += 11;
} else {
puts("=");
}
}
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 > 0 && !header)
puts("=");
return linelen;
}
static const char *
basenam(const char *s)
{
char *r = strrchr(s, '/');
return r ? r + 1 : s;
}
static void
gen_attachment(const char *filename, char *content_disposition)
{
const char *s = filename;
int quote = 0;
if (!*filename) {
printf("Content-Disposition: %s\n", content_disposition);
return;
}
for (s = (char *)filename; *s; s++) {
if (*s < 32 || *s == '"' || *s >= 127 || s - filename > 35)
goto rfc2231;
if (strchr(" ()<>@,;:\\/[]?=", *s))
quote = 1;
}
// filename SHOULD be an atom if possible
printf("Content-Disposition: %s; filename=%s%s%s\n", content_disposition,
quote ? "\"" : "", filename, quote ? "\"" : "");
return;
rfc2231:
printf("Content-Disposition: %s", content_disposition);
int i = 0;
int d = 0;
s = filename;
while (*s) {
i = printf(";\n filename*%d*=", d);
if (d++ == 0) {
printf("UTF-8''");
i += 7;
}
while (*s && i < 78 - 3) {
if (*s <= 32 || *s == '"' || *s > 126)
i += printf("%%%02x", (uint8_t)*s++);
else
i += printf("%c", (uint8_t)*s++);
}
}
printf("\n");
}
int
gen_file(char *file, char *ct)
{
uint8_t *content;
off_t size;
char *cd = "attachment";
char *s = strchr(ct, '#');
if (s) {
*s = 0;
cd = s + 1;
}
const char *filename = basenam(file);
s = strchr(file, '>');
if (s) {
*s = 0;
filename = s + 1;
}
int r = slurp(file, (char **)&content, &size);
if (r != 0) {
fprintf(stderr, "mmime: error attaching file '%s': %s\n",
file, strerror(r));
return -1;
}
if (strcmp(ct, "mblaze/raw") == 0)
goto raw;
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++;
}
gen_attachment(filename, cd);
if (strcmp(ct, "message/rfc822") == 0) {
printf("Content-Type: %s\n", ct);
printf("Content-Transfer-Encoding: %dbit\n\n",
(bitlow > 0 || bithigh > 0) ? 8 : 7);
fwrite(content, 1, size, stdout);
return 0;
}
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");
raw:
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; // was the previous word encoded as qp?
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++;
}
if (!highbit) {
if (e-s >= 998)
goto force_qp;
if (e-s >= 78 - linelen) {
// wrap in advance before long word
printf("\n");
linelen = 0;
}
if (linelen <= 1 && s[0] == ' ' && s[1] == ' ') {
// space at beginning of line
goto force_qp;
}
if (*s != ' ') {
printf(" ");
linelen++;
}
fwrite(s, 1, e-s, stdout);
linelen += e-s;
prevq = 0;
} else {
force_qp:
if (!prevq && *s == ' ')
s++;
if (linelen >= 78 - 13 - 4 ||
(e-s < (78 - 13)/3 &&
e-s >= (78 - linelen - 13)/3)) {
// wrap in advance
printf("\n");
linelen = 0;
}
printf(" =?UTF-8?Q?");
linelen += 11;
linelen = gen_qp((uint8_t *)s, e-s, 78, linelen);
printf("?=");
linelen += 2;
prevq = 1;
}
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: %s; boundary=\"%s\"\n", tflag, 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 maxheadlinelen = 0;
off_t maxbodylinelen = 0;
int c;
int l = -1;
while ((c = getchar()) != EOF) {
if (c == '\n') {
if (maxheadlinelen < linelen)
maxheadlinelen = linelen;
linelen = 0;
if (l == '\n')
break;
} else {
linelen++;
}
if (c != '\t' && c != '\n' && c < 32)
bitlow++;
if (c > 127)
bithigh++;
l = c;
}
while ((c = getchar()) != EOF) {
if (c == '\n') {
if (maxbodylinelen < linelen)
maxbodylinelen = linelen;
linelen = 0;
} else {
linelen++;
}
if (c != '\t' && c != '\n' && c < 32)
bitlow++;
if (c > 127)
bithigh++;
l = c;
}
if (bitlow == 0 && bithigh == 0 &&
maxheadlinelen < 998 && maxbodylinelen <= 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, "crt:")) != -1)
switch (c) {
case 'r': rflag = 1; break;
case 'c': cflag = 1; break;
case 't': tflag = optarg; break;
default:
usage:
fprintf(stderr,
"Usage: mmime [-c|-r] [-t CONTENT-TYPE] < message\n");
exit(1);
}
if (argc != optind)
goto usage;
if (cflag)
return check();
return gen_build();
}