diff --git a/Documentation/config.txt b/Documentation/config.txt index 306b679e48b350..5e86fe97d25db9 100644 --- a/Documentation/config.txt +++ b/Documentation/config.txt @@ -517,6 +517,8 @@ include::config/sequencer.txt[] include::config/showbranch.txt[] +include::config/sideband.txt[] + include::config/sparse.txt[] include::config/splitindex.txt[] diff --git a/Documentation/config/sideband.txt b/Documentation/config/sideband.txt new file mode 100644 index 00000000000000..f347fd6b33004a --- /dev/null +++ b/Documentation/config/sideband.txt @@ -0,0 +1,16 @@ +sideband.allowControlCharacters:: + By default, control characters that are delivered via the sideband + are masked, except ANSI color sequences. This prevents potentially + unwanted ANSI escape sequences from being sent to the terminal. Use + this config setting to override this behavior: ++ +-- + color:: + Allow ANSI color sequences, line feeds and horizontal tabs, + but mask all other control characters. This is the default. + false:: + Mask all control characters other than line feeds and + horizontal tabs. + true:: + Allow all control characters to be sent to the terminal. +-- diff --git a/sideband.c b/sideband.c index 5d8907151fec39..11332dcea3d999 100644 --- a/sideband.c +++ b/sideband.c @@ -23,6 +23,12 @@ static struct keyword_entry keywords[] = { { "error", GIT_COLOR_BOLD_RED }, }; +static enum { + ALLOW_NO_CONTROL_CHARACTERS = 0, + ALLOW_ALL_CONTROL_CHARACTERS = 1, + ALLOW_ANSI_COLOR_SEQUENCES = 2 +} allow_control_characters = ALLOW_ANSI_COLOR_SEQUENCES; + /* Returns a color setting (GIT_COLOR_NEVER, etc). */ static int use_sideband_colors(void) { @@ -36,6 +42,25 @@ static int use_sideband_colors(void) if (use_sideband_colors_cached >= 0) return use_sideband_colors_cached; + switch (git_config_get_maybe_bool("sideband.allowcontrolcharacters", &i)) { + case 0: /* Boolean value */ + allow_control_characters = i ? ALLOW_ALL_CONTROL_CHARACTERS : + ALLOW_NO_CONTROL_CHARACTERS; + break; + case -1: /* non-Boolean value */ + if (git_config_get_string("sideband.allowcontrolcharacters", + &value)) + ; /* huh? `get_maybe_bool()` returned -1 */ + else if (!strcmp(value, "color")) + allow_control_characters = ALLOW_ANSI_COLOR_SEQUENCES; + else + warning(_("unrecognized value for `sideband." + "allowControlCharacters`: '%s'"), value); + break; + default: + break; /* not configured */ + } + if (!git_config_get_string(key, &value)) { use_sideband_colors_cached = git_config_colorbool(key, value); } else if (!git_config_get_string("color.ui", &value)) { @@ -64,6 +89,55 @@ void list_config_color_sideband_slots(struct string_list *list, const char *pref list_config_item(list, prefix, keywords[i].keyword); } +static int handle_ansi_color_sequence(struct strbuf *dest, const char *src, int n) +{ + int i; + + /* + * Valid ANSI color sequences are of the form + * + * ESC [ [ [; ]*] m + */ + + if (allow_control_characters != ALLOW_ANSI_COLOR_SEQUENCES || + n < 3 || src[0] != '\x1b' || src[1] != '[') + return 0; + + for (i = 2; i < n; i++) { + if (src[i] == 'm') { + strbuf_add(dest, src, i + 1); + return i; + } + if (!isdigit(src[i]) && src[i] != ';') + break; + } + + return 0; +} + +static void strbuf_add_sanitized(struct strbuf *dest, const char *src, int n) +{ + int i; + + if (allow_control_characters == ALLOW_ALL_CONTROL_CHARACTERS) { + strbuf_add(dest, src, n); + return; + } + + strbuf_grow(dest, n); + for (; n && *src; src++, n--) { + if (!iscntrl(*src) || *src == '\t' || *src == '\n') + strbuf_addch(dest, *src); + else if ((i = handle_ansi_color_sequence(dest, src, n))) { + src += i; + n -= i; + } else { + strbuf_addch(dest, '^'); + strbuf_addch(dest, 0x40 + *src); + } + } +} + /* * Optionally highlight one keyword in remote output if it appears at the start * of the line. This should be called for a single line only, which is @@ -79,7 +153,7 @@ static void maybe_colorize_sideband(struct strbuf *dest, const char *src, int n) int i; if (!want_color_stderr(use_sideband_colors())) { - strbuf_add(dest, src, n); + strbuf_add_sanitized(dest, src, n); return; } @@ -112,7 +186,7 @@ static void maybe_colorize_sideband(struct strbuf *dest, const char *src, int n) } } - strbuf_add(dest, src, n); + strbuf_add_sanitized(dest, src, n); } diff --git a/t/t5409-colorize-remote-messages.sh b/t/t5409-colorize-remote-messages.sh index fa5de4500a4f50..a755c49a74e634 100755 --- a/t/t5409-colorize-remote-messages.sh +++ b/t/t5409-colorize-remote-messages.sh @@ -98,4 +98,34 @@ test_expect_success 'fallback to color.ui' ' grep "error: error" decoded ' +test_expect_success 'disallow (color) control sequences in sideband' ' + write_script .git/color-me-surprised <<-\EOF && + printf "error: Have you \\033[31mread\\033[m this?\\a\\n" >&2 + exec "$@" + EOF + test_config_global uploadPack.packObjectshook ./color-me-surprised && + test_commit need-at-least-one-commit && + + git clone --no-local . throw-away 2>stderr && + test_decode_color decoded && + test_grep RED decoded && + test_grep "\\^G" stderr && + tr -dc "\\007" actual && + test_must_be_empty actual && + + rm -rf throw-away && + git -c sideband.allowControlCharacters=false \ + clone --no-local . throw-away 2>stderr && + test_decode_color decoded && + test_grep ! RED decoded && + test_grep "\\^G" stderr && + + rm -rf throw-away && + git -c sideband.allowControlCharacters clone --no-local . throw-away 2>stderr && + test_decode_color decoded && + test_grep RED decoded && + tr -dc "\\007" actual && + test_file_not_empty actual +' + test_done