imapfilter/src/namespace.c
Lefteris Chatzimparmpas e03e52dba2 Correct international mailbox names conversions
Some ASCII characters in mailbox names where converted to UTF-7 while
they shouldn't.
2012-01-19 01:26:27 +01:00

298 lines
6.1 KiB
C

#include <stdio.h>
#include <string.h>
#include <iconv.h>
#include <errno.h>
#include "imapfilter.h"
#include "buffer.h"
buffer nbuf; /* Namespace buffer. */
buffer cbuf; /* Conversion buffer. */
const char *apply_conversion(const char *mbox);
const char *reverse_conversion(const char *mbox);
/*
* Convert the names of personal mailboxes, using the namespace specified
* by the mail server, from internal to mail server format.
*/
const char *
apply_namespace(const char *mbox, char *prefix, char delim)
{
int n;
char *c;
const char *m;
if (!strcasecmp(mbox, "INBOX"))
return mbox;
m = apply_conversion(mbox);
if ((prefix == NULL && delim == '\0') ||
(prefix == NULL && delim == '/'))
return m;
buffer_reset(&nbuf);
n = snprintf(nbuf.data, nbuf.size + 1, "%s%s", (prefix ? prefix : ""),
m);
if (n > (int)nbuf.size) {
buffer_check(&nbuf, n);
snprintf(nbuf.data, nbuf.size + 0, "%s%s",
(prefix ? prefix : ""), m);
}
for (c = nbuf.data; (c = strchr(c, '/')) != NULL; *(c++) = delim);
debug("namespace: '%s' -> '%s'\n", m, nbuf.data);
return nbuf.data;
}
/*
* Convert the names of personal mailboxes, using the namespace specified by
* the mail server, from mail server format to internal format.
*/
const char *
reverse_namespace(const char *mbox, char *prefix, char delim)
{
int n, o;
char *c;
if (!strcasecmp(mbox, "INBOX"))
return mbox;
if ((prefix == NULL && delim == '\0') ||
(prefix == NULL && delim == '/'))
return reverse_conversion(mbox);
buffer_reset(&nbuf);
o = strlen(prefix ? prefix : "");
if (strncasecmp(mbox, (prefix ? prefix : ""), o))
o = 0;
n = snprintf(nbuf.data, nbuf.size + 1, "%s", mbox + o);
if (n > (int)nbuf.size) {
buffer_check(&nbuf, n);
snprintf(nbuf.data, nbuf.size + 1, "%s", mbox + o);
}
for (c = nbuf.data; (c = strchr(c, delim)) != NULL; *(c++) = '/');
debug("namespace: '%s' <- '%s'\n", mbox, nbuf.data);
return reverse_conversion(nbuf.data);
}
/*
* Convert a mailbox name to the modified UTF-7 encoding, according to RFC 3501
* Section 5.1.3.
*/
const char *
apply_conversion(const char *mbox)
{
iconv_t cd;
char *inbuf, *outbuf;
size_t inlen, outlen;
char *c, *shift;
unsigned char *r, *w;
buffer_check(&nbuf, strlen(mbox));
buffer_reset(&nbuf);
xstrncpy(nbuf.data, mbox, nbuf.size);
nbuf.len = strlen(nbuf.data);
buffer_check(&cbuf, nbuf.len * 5);
buffer_reset(&cbuf);
r = (unsigned char *)nbuf.data;
w = (unsigned char *)cbuf.data;
inbuf = outbuf = NULL;
inlen = outlen = 0;
while (*r != '\0') {
/* Skip non-printable ASCII characters. */
if (*r < 0x20 || *r == 0x7F) {
r++;
continue;
}
/* Escape shift character for modified UTF-7. */
if (*r == '&') {
*w++ = '&';
*w++ = '-';
r++;
continue;
}
/* Copy ASCII printable characters. */
if (*r >= 0x20 && *r <= 0x7E) {
*w++ = *r++;
continue;
}
/* UTF-8 sequence will follow. */
if (inbuf == NULL) {
inbuf = (char *)r;
inlen = 0;
}
if ((*r & 0xE0) == 0xC0) { /* Two byte UTF-8. */
inlen += 2;
r += 2;
} else if ((*r & 0xF0) == 0xE0) { /* Three byte UTF-8. */
inlen += 3;
r += 3;
} else if ((*r & 0xF8) == 0xF0) { /* Four byte UTF-8. */
inlen += 4;
r += 4;
}
/* UTF-8 sequence has ended, convert it to UTF-7. */
if (inbuf != NULL && (*r <= 0x7F || *r == '\0')) {
outbuf = (char *)w;
outlen = cbuf.size - (outbuf - cbuf.data);
cd = iconv_open("UTF-7", "");
if (cd == (iconv_t)-1) {
error("converting mailbox name; %s\n",
strerror(errno));
return mbox;
}
while (inlen > 0) {
if (iconv(cd, &inbuf, &inlen, &outbuf, &outlen)
== -1) {
if (errno == E2BIG) {
buffer_check(&cbuf, cbuf.size *
2);
break;
} else {
error("converting mailbox name;"
"%s\n", strerror(errno));
return mbox;
}
} else {
iconv(cd, NULL, NULL, &outbuf, &outlen);
}
}
iconv_close(cd);
w = (unsigned char *)outbuf;
inbuf = outbuf = NULL;
inlen = outlen = 0;
}
}
if (*w != '\0')
*w = '\0';
/* Convert UTF-7 sequences to IMAP modified UTF-7. */
for (c = cbuf.data, shift = NULL; *c != '\0'; c++)
switch (*c) {
case '+':
*c = '&';
shift = c;
break;
case '-':
shift = NULL;
break;
case '/':
if (shift != NULL)
*c = ',';
break;
}
if (shift != NULL) {
*w++ = '-';
*w = '\0';
}
debug("conversion: '%s' -> '%s'\n", nbuf.data, cbuf.data);
return cbuf.data;
}
/*
* Convert a mailbox name from the modified UTF-7 encoding, according to RFC
* 3501 Section 5.1.3.
*/
const char *
reverse_conversion(const char *mbox)
{
iconv_t cd;
char *inbuf, *outbuf;
size_t inlen, outlen;
char *c, *shift;
buffer_check(&cbuf, strlen(mbox));
buffer_reset(&cbuf);
xstrncpy(cbuf.data, mbox, cbuf.size);
/* Convert IMAP modified UTF-7 sequences to UTF-7. */
for (c = cbuf.data, shift = NULL; *c != '\0'; c++)
switch (*c) {
case '&':
*c = '+';
shift = c;
break;
case '-':
shift = NULL;
break;
case ',':
if (shift != NULL)
*c = '/';
break;
}
do {
inbuf = cbuf.data;
inlen = strlen(cbuf.data);
buffer_check(&nbuf, inlen);
buffer_reset(&nbuf);
outbuf = nbuf.data;
outlen = nbuf.size;
cd = iconv_open("", "UTF-7");
if (cd == (iconv_t)-1) {
error("converting mailbox name; %s\n", strerror(errno));
return mbox;
}
while (inlen > 0) {
if (iconv(cd, &inbuf, &inlen, &outbuf, &outlen) == -1) {
if (errno == E2BIG) {
buffer_check(&nbuf, nbuf.size * 2);
break;
} else {
error("converting mailbox name; %s\n",
strerror(errno));
return mbox;
}
} else {
iconv(cd, NULL, NULL, &outbuf, &outlen);
}
}
iconv_close(cd);
} while (inlen > 0);
*outbuf = '\0';
for (c = nbuf.data; (c = strchr(c,'+')) != NULL; *c = '&');
/* Convert UTF-7 sequences to IMAP modified UTF-7. */
for (c = cbuf.data, shift = NULL; *c != '\0'; c++)
switch (*c) {
case '+':
*c = '&';
shift = c;
break;
case '-':
shift = NULL;
break;
case '/':
if (shift != NULL)
*c = ',';
break;
}
debug("conversion: '%s' <- '%s'\n", nbuf.data, cbuf.data);
return nbuf.data;
}