When an SMTP server receives an 8-bit email message, possibly with only LF as line ending, some of those servers decide to change said LF to CRLF. Some other SMTP servers, when receives an 8-bit email message, decide to encoding such message in base64 and/or quoted-printable instead. If an email is transfered through those 2 email servers in order, the final recipients will receive an email contains a patch mungled with CRLF encoded inside another encoding. Thus, such CR couldn't be dropped by mailsplit. Such accidents have been observed in the wild [1]. Let's guess if such CR was added automatically and strip them in mailinfo. [1]: https://nmbug.notmuchmail.org/nmweb/show/m2lf9ejegj.fsf%40guru.guru-group.fi Signed-off-by: Đoàn Trần Công Danh <congdanhqx@xxxxxxxxx> --- I'm not sure if guessing the heuristic to strip CR is a good approach. I think it's better to pass --keep-cr down from git-am. Let's say --keep-cr=<yes|no|auto> mailinfo.c | 20 +++++++++++++++++--- t/t5100-mailinfo.sh | 5 +++++ t/t5100/cr-base64.mbox | 22 ++++++++++++++++++++++ t/t5100/info1000 | 5 +++++ t/t5100/msg1000 | 2 ++ t/t5100/patch1000 | 22 ++++++++++++++++++++++ 6 files changed, 73 insertions(+), 3 deletions(-) create mode 100644 t/t5100/cr-base64.mbox create mode 100644 t/t5100/info1000 create mode 100644 t/t5100/msg1000 create mode 100644 t/t5100/patch1000 diff --git a/mailinfo.c b/mailinfo.c index 5681d9130d..dbff867f42 100644 --- a/mailinfo.c +++ b/mailinfo.c @@ -988,16 +988,27 @@ static int handle_boundary(struct mailinfo *mi, struct strbuf *line) } static void handle_filter_flowed(struct mailinfo *mi, struct strbuf *line, - struct strbuf *prev) + struct strbuf *prev, int *keep_cr) { size_t len = line->len; const char *rest; if (!mi->format_flowed) { + if (*keep_cr == -1 && len >= 2) + *keep_cr = !(line->buf[len - 2] == '\r' && + line->buf[len - 1] == '\n'); + if (!*keep_cr && len >= 2 && + line->buf[len - 2] == '\r' && + line->buf[len - 1] == '\n') { + strbuf_setlen(line, len - 2); + strbuf_addch(line, '\n'); + len--; + } handle_filter(mi, line); return; } + *keep_cr = 1; if (line->buf[len - 1] == '\n') { len--; if (len && line->buf[len - 1] == '\r') @@ -1036,6 +1047,7 @@ static void handle_filter_flowed(struct mailinfo *mi, struct strbuf *line, static void handle_body(struct mailinfo *mi, struct strbuf *line) { struct strbuf prev = STRBUF_INIT; + int keep_cr = -1; /* Skip up to the first boundary */ if (*(mi->content_top)) { @@ -1081,7 +1093,7 @@ static void handle_body(struct mailinfo *mi, struct strbuf *line) strbuf_addbuf(&prev, sb); break; } - handle_filter_flowed(mi, sb, &prev); + handle_filter_flowed(mi, sb, &prev, &keep_cr); } /* * The partial chunk is saved in "prev" and will be @@ -1091,7 +1103,9 @@ static void handle_body(struct mailinfo *mi, struct strbuf *line) break; } default: - handle_filter_flowed(mi, line, &prev); + /* CR in plain message was processed in mailsplit */ + keep_cr = 1; + handle_filter_flowed(mi, line, &prev, &keep_cr); } if (mi->input_error) diff --git a/t/t5100-mailinfo.sh b/t/t5100-mailinfo.sh index 147e616533..9ccc11d16a 100755 --- a/t/t5100-mailinfo.sh +++ b/t/t5100-mailinfo.sh @@ -228,4 +228,9 @@ test_expect_success 'mailinfo handles unusual header whitespace' ' test_cmp expect actual ' +test_expect_success 'mailinfo strip CR after decode base64' ' + cp $DATA/cr-base64.mbox 1000 && + check_mailinfo 1000 "" +' + test_done diff --git a/t/t5100/cr-base64.mbox b/t/t5100/cr-base64.mbox new file mode 100644 index 0000000000..6ea9806a6b --- /dev/null +++ b/t/t5100/cr-base64.mbox @@ -0,0 +1,22 @@ +From: A U Thor <mail@xxxxxxxxxxx> +To: list@xxxxxxxxxxx +Subject: [PATCH v2] sample +Date: Mon, 3 Aug 2020 22:40:55 +0700 +Message-Id: <msg-id@xxxxxxxxxxx> +Content-Type: text/plain; charset="utf-8" +Content-Transfer-Encoding: base64 + +T24gZGlmZmVyZW50IGRpc3RybywgcHl0ZXN0IGlzIHN1ZmZpeGVkIHdpdGggZGlmZmVyZW50IHBh +dHRlcm5zLg0KDQotLS0NCiBjb25maWd1cmUgfCAyICstDQogMSBmaWxlIGNoYW5nZWQsIDEgaW5z +ZXJ0aW9uKCspLCAxIGRlbGV0aW9uKC0pDQoNCmRpZmYgLS1naXQgYS9jb25maWd1cmUgYi9jb25m +aWd1cmUNCmluZGV4IGRiMzUzOGIzLi5mN2MxYzA5NSAxMDA3NTUNCi0tLSBhL2NvbmZpZ3VyZQ0K +KysrIGIvY29uZmlndXJlDQpAQCAtODE0LDcgKzgxNCw3IEBAIGlmIFsgJGhhdmVfcHl0aG9uMyAt +ZXEgMSBdOyB0aGVuDQogICAgIHByaW50ZiAiQ2hlY2tpbmcgZm9yIHB5dGhvbjMgcHl0ZXN0ICg+ +PSAzLjApLi4uICINCiAgICAgY29uZj0kKG1rdGVtcCkNCiAgICAgcHJpbnRmICJbcHl0ZXN0XVxu +bWludmVyc2lvbj0zLjBcbiIgPiAkY29uZg0KLSAgICBpZiBweXRlc3QtMyAtYyAkY29uZiAtLXZl +cnNpb24gPi9kZXYvbnVsbCAyPiYxOyB0aGVuDQorICAgIGlmICIkcHl0aG9uIiAtbSBweXRlc3Qg +LWMgJGNvbmYgLS12ZXJzaW9uID4vZGV2L251bGwgMj4mMTsgdGhlbg0KICAgICAgICAgcHJpbnRm +ICJZZXMuXG4iDQogICAgICAgICBoYXZlX3B5dGhvbjNfcHl0ZXN0PTENCiAgICAgZWxzZQ0KLS0g +DQoyLjI4LjANCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f +CmV4YW1wbGUgbWFpbGluZyBsaXN0IC0tIGxpc3RAZXhhbXBsZS5vcmcKVG8gdW5zdWJzY3JpYmUg +c2VuZCBhbiBlbWFpbCB0byBsaXN0LWxlYXZlQGV4YW1wbGUub3JnCg== diff --git a/t/t5100/info1000 b/t/t5100/info1000 new file mode 100644 index 0000000000..dab2228b70 --- /dev/null +++ b/t/t5100/info1000 @@ -0,0 +1,5 @@ +Author: A U Thor +Email: mail@xxxxxxxxxxx +Subject: sample +Date: Mon, 3 Aug 2020 22:40:55 +0700 + diff --git a/t/t5100/msg1000 b/t/t5100/msg1000 new file mode 100644 index 0000000000..5e8e860aae --- /dev/null +++ b/t/t5100/msg1000 @@ -0,0 +1,2 @@ +On different distro, pytest is suffixed with different patterns. + diff --git a/t/t5100/patch1000 b/t/t5100/patch1000 new file mode 100644 index 0000000000..51c4fb4cb5 --- /dev/null +++ b/t/t5100/patch1000 @@ -0,0 +1,22 @@ +--- + configure | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/configure b/configure +index db3538b3..f7c1c095 100755 +--- a/configure ++++ b/configure +@@ -814,7 +814,7 @@ if [ $have_python3 -eq 1 ]; then + printf "Checking for python3 pytest (>= 3.0)... " + conf=$(mktemp) + printf "[pytest]\nminversion=3.0\n" > $conf +- if pytest-3 -c $conf --version >/dev/null 2>&1; then ++ if "$python" -m pytest -c $conf --version >/dev/null 2>&1; then + printf "Yes.\n" + have_python3_pytest=1 + else +-- +2.28.0 +_______________________________________________ +example mailing list -- list@xxxxxxxxxxx +To unsubscribe send an email to list-leave@xxxxxxxxxxx -- 2.31.1.192.g0881477623
