git/builtin-mailinfo.c
Jay Soffian 87f1b8849b mailinfo: feed only one line to handle_filter() for QP input
The function is intended to be fed one logical line at a time to
inspect, but a QP encoded raw input line can have more than one
lines, just like BASE64 encoded one.

Quoting LF as =0A may be unusual but RFC2045 allows it.

The issue was noticed and fixed by Jay Soffian.  JC added a test
to protect the fix from regressing later.

Signed-off-by: Jay Soffian <jaysoffian@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-02-15 22:16:34 -08:00

989 lines
20 KiB
C

/*
* Another stupid program, this one parsing the headers of an
* email to figure out authorship and subject
*/
#include "cache.h"
#include "builtin.h"
#include "utf8.h"
static FILE *cmitmsg, *patchfile, *fin, *fout;
static int keep_subject;
static const char *metainfo_charset;
static char line[1000];
static char name[1000];
static char email[1000];
static enum {
TE_DONTCARE, TE_QP, TE_BASE64,
} transfer_encoding;
static enum {
TYPE_TEXT, TYPE_OTHER,
} message_type;
static char charset[256];
static int patch_lines;
static char **p_hdr_data, **s_hdr_data;
#define MAX_HDR_PARSED 10
#define MAX_BOUNDARIES 5
static char *sanity_check(char *name, char *email)
{
int len = strlen(name);
if (len < 3 || len > 60)
return email;
if (strchr(name, '@') || strchr(name, '<') || strchr(name, '>'))
return email;
return name;
}
static int bogus_from(char *line)
{
/* John Doe <johndoe> */
char *bra, *ket, *dst, *cp;
/* This is fallback, so do not bother if we already have an
* e-mail address.
*/
if (*email)
return 0;
bra = strchr(line, '<');
if (!bra)
return 0;
ket = strchr(bra, '>');
if (!ket)
return 0;
for (dst = email, cp = bra+1; cp < ket; )
*dst++ = *cp++;
*dst = 0;
for (cp = line; isspace(*cp); cp++)
;
for (bra--; isspace(*bra); bra--)
*bra = 0;
cp = sanity_check(cp, email);
strcpy(name, cp);
return 1;
}
static int handle_from(char *in_line)
{
char line[1000];
char *at;
char *dst;
strcpy(line, in_line);
at = strchr(line, '@');
if (!at)
return bogus_from(line);
/*
* If we already have one email, don't take any confusing lines
*/
if (*email && strchr(at+1, '@'))
return 0;
/* Pick up the string around '@', possibly delimited with <>
* pair; that is the email part. White them out while copying.
*/
while (at > line) {
char c = at[-1];
if (isspace(c))
break;
if (c == '<') {
at[-1] = ' ';
break;
}
at--;
}
dst = email;
for (;;) {
unsigned char c = *at;
if (!c || c == '>' || isspace(c)) {
if (c == '>')
*at = ' ';
break;
}
*at++ = ' ';
*dst++ = c;
}
*dst++ = 0;
/* The remainder is name. It could be "John Doe <john.doe@xz>"
* or "john.doe@xz (John Doe)", but we have whited out the
* email part, so trim from both ends, possibly removing
* the () pair at the end.
*/
at = line + strlen(line);
while (at > line) {
unsigned char c = *--at;
if (!isspace(c)) {
at[(c == ')') ? 0 : 1] = 0;
break;
}
}
at = line;
for (;;) {
unsigned char c = *at;
if (!c || !isspace(c)) {
if (c == '(')
at++;
break;
}
at++;
}
at = sanity_check(at, email);
strcpy(name, at);
return 1;
}
static int handle_header(char *line, char *data, int ofs)
{
if (!line || !data)
return 1;
strcpy(data, line+ofs);
return 0;
}
/* NOTE NOTE NOTE. We do not claim we do full MIME. We just attempt
* to have enough heuristics to grok MIME encoded patches often found
* on our mailing lists. For example, we do not even treat header lines
* case insensitively.
*/
static int slurp_attr(const char *line, const char *name, char *attr)
{
const char *ends, *ap = strcasestr(line, name);
size_t sz;
if (!ap) {
*attr = 0;
return 0;
}
ap += strlen(name);
if (*ap == '"') {
ap++;
ends = "\"";
}
else
ends = "; \t";
sz = strcspn(ap, ends);
memcpy(attr, ap, sz);
attr[sz] = 0;
return 1;
}
struct content_type {
char *boundary;
int boundary_len;
};
static struct content_type content[MAX_BOUNDARIES];
static struct content_type *content_top = content;
static int handle_content_type(char *line)
{
char boundary[256];
if (strcasestr(line, "text/") == NULL)
message_type = TYPE_OTHER;
if (slurp_attr(line, "boundary=", boundary + 2)) {
memcpy(boundary, "--", 2);
if (content_top++ >= &content[MAX_BOUNDARIES]) {
fprintf(stderr, "Too many boundaries to handle\n");
exit(1);
}
content_top->boundary_len = strlen(boundary);
content_top->boundary = xmalloc(content_top->boundary_len+1);
strcpy(content_top->boundary, boundary);
}
if (slurp_attr(line, "charset=", charset)) {
int i, c;
for (i = 0; (c = charset[i]) != 0; i++)
charset[i] = tolower(c);
}
return 0;
}
static int handle_content_transfer_encoding(char *line)
{
if (strcasestr(line, "base64"))
transfer_encoding = TE_BASE64;
else if (strcasestr(line, "quoted-printable"))
transfer_encoding = TE_QP;
else
transfer_encoding = TE_DONTCARE;
return 0;
}
static int is_multipart_boundary(const char *line)
{
return (!memcmp(line, content_top->boundary, content_top->boundary_len));
}
static int eatspace(char *line)
{
int len = strlen(line);
while (len > 0 && isspace(line[len-1]))
line[--len] = 0;
return len;
}
static char *cleanup_subject(char *subject)
{
for (;;) {
char *p;
int len, remove;
switch (*subject) {
case 'r': case 'R':
if (!memcmp("e:", subject+1, 2)) {
subject += 3;
continue;
}
break;
case ' ': case '\t': case ':':
subject++;
continue;
case '[':
p = strchr(subject, ']');
if (!p) {
subject++;
continue;
}
len = strlen(p);
remove = p - subject;
if (remove <= len *2) {
subject = p+1;
continue;
}
break;
}
eatspace(subject);
return subject;
}
}
static void cleanup_space(char *buf)
{
unsigned char c;
while ((c = *buf) != 0) {
buf++;
if (isspace(c)) {
buf[-1] = ' ';
c = *buf;
while (isspace(c)) {
int len = strlen(buf);
memmove(buf, buf+1, len);
c = *buf;
}
}
}
}
static void decode_header(char *it, unsigned itsize);
static const char *header[MAX_HDR_PARSED] = {
"From","Subject","Date",
};
static int check_header(char *line, unsigned linesize, char **hdr_data, int overwrite)
{
int i;
/* search for the interesting parts */
for (i = 0; header[i]; i++) {
int len = strlen(header[i]);
if ((!hdr_data[i] || overwrite) &&
!strncasecmp(line, header[i], len) &&
line[len] == ':' && isspace(line[len + 1])) {
/* Unwrap inline B and Q encoding, and optionally
* normalize the meta information to utf8.
*/
decode_header(line + len + 2, linesize - len - 2);
hdr_data[i] = xmalloc(1000 * sizeof(char));
if (! handle_header(line, hdr_data[i], len + 2)) {
return 1;
}
}
}
/* Content stuff */
if (!strncasecmp(line, "Content-Type", 12) &&
line[12] == ':' && isspace(line[12 + 1])) {
decode_header(line + 12 + 2, linesize - 12 - 2);
if (! handle_content_type(line)) {
return 1;
}
}
if (!strncasecmp(line, "Content-Transfer-Encoding", 25) &&
line[25] == ':' && isspace(line[25 + 1])) {
decode_header(line + 25 + 2, linesize - 25 - 2);
if (! handle_content_transfer_encoding(line)) {
return 1;
}
}
/* for inbody stuff */
if (!memcmp(">From", line, 5) && isspace(line[5]))
return 1;
if (!memcmp("[PATCH]", line, 7) && isspace(line[7])) {
for (i = 0; header[i]; i++) {
if (!memcmp("Subject: ", header[i], 9)) {
if (! handle_header(line, hdr_data[i], 0)) {
return 1;
}
}
}
}
/* no match */
return 0;
}
static int is_rfc2822_header(char *line)
{
/*
* The section that defines the loosest possible
* field name is "3.6.8 Optional fields".
*
* optional-field = field-name ":" unstructured CRLF
* field-name = 1*ftext
* ftext = %d33-57 / %59-126
*/
int ch;
char *cp = line;
/* Count mbox From headers as headers */
if (!memcmp(line, "From ", 5) || !memcmp(line, ">From ", 6))
return 1;
while ((ch = *cp++)) {
if (ch == ':')
return cp != line;
if ((33 <= ch && ch <= 57) ||
(59 <= ch && ch <= 126))
continue;
break;
}
return 0;
}
/*
* sz is size of 'line' buffer in bytes. Must be reasonably
* long enough to hold one physical real-world e-mail line.
*/
static int read_one_header_line(char *line, int sz, FILE *in)
{
int len;
/*
* We will read at most (sz-1) bytes and then potentially
* re-add NUL after it. Accessing line[sz] after this is safe
* and we can allow len to grow up to and including sz.
*/
sz--;
/* Get the first part of the line. */
if (!fgets(line, sz, in))
return 0;
/*
* Is it an empty line or not a valid rfc2822 header?
* If so, stop here, and return false ("not a header")
*/
len = eatspace(line);
if (!len || !is_rfc2822_header(line)) {
/* Re-add the newline */
line[len] = '\n';
line[len + 1] = '\0';
return 0;
}
/*
* Now we need to eat all the continuation lines..
* Yuck, 2822 header "folding"
*/
for (;;) {
int peek, addlen;
static char continuation[1000];
peek = fgetc(in); ungetc(peek, in);
if (peek != ' ' && peek != '\t')
break;
if (!fgets(continuation, sizeof(continuation), in))
break;
addlen = eatspace(continuation);
if (len < sz - 1) {
if (addlen >= sz - len)
addlen = sz - len - 1;
memcpy(line + len, continuation, addlen);
line[len] = '\n';
len += addlen;
}
}
line[len] = 0;
return 1;
}
static int decode_q_segment(char *in, char *ot, unsigned otsize, char *ep, int rfc2047)
{
char *otend = ot + otsize;
int c;
while ((c = *in++) != 0 && (in <= ep)) {
if (ot == otend) {
*--ot = '\0';
return -1;
}
if (c == '=') {
int d = *in++;
if (d == '\n' || !d)
break; /* drop trailing newline */
*ot++ = ((hexval(d) << 4) | hexval(*in++));
continue;
}
if (rfc2047 && c == '_') /* rfc2047 4.2 (2) */
c = 0x20;
*ot++ = c;
}
*ot = 0;
return 0;
}
static int decode_b_segment(char *in, char *ot, unsigned otsize, char *ep)
{
/* Decode in..ep, possibly in-place to ot */
int c, pos = 0, acc = 0;
char *otend = ot + otsize;
while ((c = *in++) != 0 && (in <= ep)) {
if (ot == otend) {
*--ot = '\0';
return -1;
}
if (c == '+')
c = 62;
else if (c == '/')
c = 63;
else if ('A' <= c && c <= 'Z')
c -= 'A';
else if ('a' <= c && c <= 'z')
c -= 'a' - 26;
else if ('0' <= c && c <= '9')
c -= '0' - 52;
else if (c == '=') {
/* padding is almost like (c == 0), except we do
* not output NUL resulting only from it;
* for now we just trust the data.
*/
c = 0;
}
else
continue; /* garbage */
switch (pos++) {
case 0:
acc = (c << 2);
break;
case 1:
*ot++ = (acc | (c >> 4));
acc = (c & 15) << 4;
break;
case 2:
*ot++ = (acc | (c >> 2));
acc = (c & 3) << 6;
break;
case 3:
*ot++ = (acc | c);
acc = pos = 0;
break;
}
}
*ot = 0;
return 0;
}
/*
* When there is no known charset, guess.
*
* Right now we assume that if the target is UTF-8 (the default),
* and it already looks like UTF-8 (which includes US-ASCII as its
* subset, of course) then that is what it is and there is nothing
* to do.
*
* Otherwise, we default to assuming it is Latin1 for historical
* reasons.
*/
static const char *guess_charset(const char *line, const char *target_charset)
{
if (is_encoding_utf8(target_charset)) {
if (is_utf8(line))
return NULL;
}
return "latin1";
}
static void convert_to_utf8(char *line, unsigned linesize, const char *charset)
{
char *out;
if (!charset || !*charset) {
charset = guess_charset(line, metainfo_charset);
if (!charset)
return;
}
if (!strcmp(metainfo_charset, charset))
return;
out = reencode_string(line, metainfo_charset, charset);
if (!out)
die("cannot convert from %s to %s\n",
charset, metainfo_charset);
strlcpy(line, out, linesize);
free(out);
}
static int decode_header_bq(char *it, unsigned itsize)
{
char *in, *out, *ep, *cp, *sp;
char outbuf[1000];
int rfc2047 = 0;
in = it;
out = outbuf;
while ((ep = strstr(in, "=?")) != NULL) {
int sz, encoding;
char charset_q[256], piecebuf[256];
rfc2047 = 1;
if (in != ep) {
sz = ep - in;
memcpy(out, in, sz);
out += sz;
in += sz;
}
/* E.g.
* ep : "=?iso-2022-jp?B?GyR...?= foo"
* ep : "=?ISO-8859-1?Q?Foo=FCbar?= baz"
*/
ep += 2;
cp = strchr(ep, '?');
if (!cp)
return rfc2047; /* no munging */
for (sp = ep; sp < cp; sp++)
charset_q[sp - ep] = tolower(*sp);
charset_q[cp - ep] = 0;
encoding = cp[1];
if (!encoding || cp[2] != '?')
return rfc2047; /* no munging */
ep = strstr(cp + 3, "?=");
if (!ep)
return rfc2047; /* no munging */
switch (tolower(encoding)) {
default:
return rfc2047; /* no munging */
case 'b':
sz = decode_b_segment(cp + 3, piecebuf, sizeof(piecebuf), ep);
break;
case 'q':
sz = decode_q_segment(cp + 3, piecebuf, sizeof(piecebuf), ep, 1);
break;
}
if (sz < 0)
return rfc2047;
if (metainfo_charset)
convert_to_utf8(piecebuf, sizeof(piecebuf), charset_q);
sz = strlen(piecebuf);
if (outbuf + sizeof(outbuf) <= out + sz)
return rfc2047; /* no munging */
strcpy(out, piecebuf);
out += sz;
in = ep + 2;
}
strcpy(out, in);
strlcpy(it, outbuf, itsize);
return rfc2047;
}
static void decode_header(char *it, unsigned itsize)
{
if (decode_header_bq(it, itsize))
return;
/* otherwise "it" is a straight copy of the input.
* This can be binary guck but there is no charset specified.
*/
if (metainfo_charset)
convert_to_utf8(it, itsize, "");
}
static void decode_transfer_encoding(char *line, unsigned linesize)
{
char *ep;
switch (transfer_encoding) {
case TE_QP:
ep = line + strlen(line);
decode_q_segment(line, line, linesize, ep, 0);
break;
case TE_BASE64:
ep = line + strlen(line);
decode_b_segment(line, line, linesize, ep);
break;
case TE_DONTCARE:
break;
}
}
static int handle_filter(char *line, unsigned linesize);
static int find_boundary(void)
{
while(fgets(line, sizeof(line), fin) != NULL) {
if (is_multipart_boundary(line))
return 1;
}
return 0;
}
static int handle_boundary(void)
{
char newline[]="\n";
again:
if (!memcmp(line+content_top->boundary_len, "--", 2)) {
/* we hit an end boundary */
/* pop the current boundary off the stack */
free(content_top->boundary);
/* technically won't happen as is_multipart_boundary()
will fail first. But just in case..
*/
if (content_top-- < content) {
fprintf(stderr, "Detected mismatched boundaries, "
"can't recover\n");
exit(1);
}
handle_filter(newline, sizeof(newline));
/* skip to the next boundary */
if (!find_boundary())
return 0;
goto again;
}
/* set some defaults */
transfer_encoding = TE_DONTCARE;
charset[0] = 0;
message_type = TYPE_TEXT;
/* slurp in this section's info */
while (read_one_header_line(line, sizeof(line), fin))
check_header(line, sizeof(line), p_hdr_data, 0);
/* eat the blank line after section info */
return (fgets(line, sizeof(line), fin) != NULL);
}
static inline int patchbreak(const char *line)
{
/* Beginning of a "diff -" header? */
if (!memcmp("diff -", line, 6))
return 1;
/* CVS "Index: " line? */
if (!memcmp("Index: ", line, 7))
return 1;
/*
* "--- <filename>" starts patches without headers
* "---<sp>*" is a manual separator
*/
if (!memcmp("---", line, 3)) {
line += 3;
/* space followed by a filename? */
if (line[0] == ' ' && !isspace(line[1]))
return 1;
/* Just whitespace? */
for (;;) {
unsigned char c = *line++;
if (c == '\n')
return 1;
if (!isspace(c))
break;
}
return 0;
}
return 0;
}
static int handle_commit_msg(char *line, unsigned linesize)
{
static int still_looking = 1;
char *endline = line + linesize;
if (!cmitmsg)
return 0;
if (still_looking) {
char *cp = line;
if (isspace(*line)) {
for (cp = line + 1; *cp; cp++) {
if (!isspace(*cp))
break;
}
if (!*cp)
return 0;
}
if ((still_looking = check_header(cp, endline - cp, s_hdr_data, 0)) != 0)
return 0;
}
/* normalize the log message to UTF-8. */
if (metainfo_charset)
convert_to_utf8(line, endline - line, charset);
if (patchbreak(line)) {
fclose(cmitmsg);
cmitmsg = NULL;
return 1;
}
fputs(line, cmitmsg);
return 0;
}
static int handle_patch(char *line)
{
fputs(line, patchfile);
patch_lines++;
return 0;
}
static int handle_filter(char *line, unsigned linesize)
{
static int filter = 0;
/* filter tells us which part we left off on
* a non-zero return indicates we hit a filter point
*/
switch (filter) {
case 0:
if (!handle_commit_msg(line, linesize))
break;
filter++;
case 1:
if (!handle_patch(line))
break;
filter++;
default:
return 1;
}
return 0;
}
static void handle_body(void)
{
int rc = 0;
static char newline[2000];
static char *np = newline;
/* Skip up to the first boundary */
if (content_top->boundary) {
if (!find_boundary())
return;
}
do {
/* process any boundary lines */
if (content_top->boundary && is_multipart_boundary(line)) {
/* flush any leftover */
if ((transfer_encoding == TE_BASE64) &&
(np != newline)) {
handle_filter(newline, sizeof(newline));
}
if (!handle_boundary())
return;
}
/* Unwrap transfer encoding */
decode_transfer_encoding(line, sizeof(line));
switch (transfer_encoding) {
case TE_BASE64:
case TE_QP:
{
char *op = line;
/* binary data most likely doesn't have newlines */
if (message_type != TYPE_TEXT) {
rc = handle_filter(line, sizeof(newline));
break;
}
/* this is a decoded line that may contain
* multiple new lines. Pass only one chunk
* at a time to handle_filter()
*/
do {
while (*op != '\n' && *op != 0)
*np++ = *op++;
*np = *op;
if (*np != 0) {
/* should be sitting on a new line */
*(++np) = 0;
op++;
rc = handle_filter(newline, sizeof(newline));
np = newline;
}
} while (*op != 0);
/* the partial chunk is saved in newline and
* will be appended by the next iteration of fgets
*/
break;
}
default:
rc = handle_filter(line, sizeof(newline));
}
if (rc)
/* nothing left to filter */
break;
} while (fgets(line, sizeof(line), fin));
return;
}
static void output_header_lines(FILE *fout, const char *hdr, char *data)
{
while (1) {
char *ep = strchr(data, '\n');
int len;
if (!ep)
len = strlen(data);
else
len = ep - data;
fprintf(fout, "%s: %.*s\n", hdr, len, data);
if (!ep)
break;
data = ep + 1;
}
}
static void handle_info(void)
{
char *sub;
char *hdr;
int i;
for (i = 0; header[i]; i++) {
/* only print inbody headers if we output a patch file */
if (patch_lines && s_hdr_data[i])
hdr = s_hdr_data[i];
else if (p_hdr_data[i])
hdr = p_hdr_data[i];
else
continue;
if (!memcmp(header[i], "Subject", 7)) {
if (keep_subject)
sub = hdr;
else {
sub = cleanup_subject(hdr);
cleanup_space(sub);
}
output_header_lines(fout, "Subject", sub);
} else if (!memcmp(header[i], "From", 4)) {
handle_from(hdr);
fprintf(fout, "Author: %s\n", name);
fprintf(fout, "Email: %s\n", email);
} else {
cleanup_space(hdr);
fprintf(fout, "%s: %s\n", header[i], hdr);
}
}
fprintf(fout, "\n");
}
static int mailinfo(FILE *in, FILE *out, int ks, const char *encoding,
const char *msg, const char *patch)
{
int peek;
keep_subject = ks;
metainfo_charset = encoding;
fin = in;
fout = out;
cmitmsg = fopen(msg, "w");
if (!cmitmsg) {
perror(msg);
return -1;
}
patchfile = fopen(patch, "w");
if (!patchfile) {
perror(patch);
fclose(cmitmsg);
return -1;
}
p_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(char *));
s_hdr_data = xcalloc(MAX_HDR_PARSED, sizeof(char *));
do {
peek = fgetc(in);
} while (isspace(peek));
ungetc(peek, in);
/* process the email header */
while (read_one_header_line(line, sizeof(line), fin))
check_header(line, sizeof(line), p_hdr_data, 1);
handle_body();
handle_info();
return 0;
}
static const char mailinfo_usage[] =
"git-mailinfo [-k] [-u | --encoding=<encoding>] msg patch <mail >info";
int cmd_mailinfo(int argc, const char **argv, const char *prefix)
{
const char *def_charset;
/* NEEDSWORK: might want to do the optional .git/ directory
* discovery
*/
git_config(git_default_config);
def_charset = (git_commit_encoding ? git_commit_encoding : "utf-8");
metainfo_charset = def_charset;
while (1 < argc && argv[1][0] == '-') {
if (!strcmp(argv[1], "-k"))
keep_subject = 1;
else if (!strcmp(argv[1], "-u"))
metainfo_charset = def_charset;
else if (!strcmp(argv[1], "-n"))
metainfo_charset = NULL;
else if (!prefixcmp(argv[1], "--encoding="))
metainfo_charset = argv[1] + 11;
else
usage(mailinfo_usage);
argc--; argv++;
}
if (argc != 3)
usage(mailinfo_usage);
return !!mailinfo(stdin, stdout, keep_subject, metainfo_charset, argv[1], argv[2]);
}