diff --git a/Documentation/config.adoc b/Documentation/config.adoc index 62eebe7c54..dcea3c0c15 100644 --- a/Documentation/config.adoc +++ b/Documentation/config.adoc @@ -523,6 +523,8 @@ include::config/sequencer.adoc[] include::config/showbranch.adoc[] +include::config/sideband.adoc[] + include::config/sparse.adoc[] include::config/splitindex.adoc[] diff --git a/Documentation/config/sideband.adoc b/Documentation/config/sideband.adoc new file mode 100644 index 0000000000..32088bbf2f --- /dev/null +++ b/Documentation/config/sideband.adoc @@ -0,0 +1,28 @@ +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 (the value can be + a comma-separated list of the following keywords): ++ +-- + `default`:: + `color`:: + Allow ANSI color sequences, line feeds and horizontal tabs, + but mask all other control characters. This is the default. + `cursor:`: + Allow control sequences that move the cursor. This is + disabled by default. + `erase`:: + Allow control sequences that erase charactrs. This is + disabled by default. + `false`:: + Mask all control characters other than line feeds and + horizontal tabs. + `true`:: + Allow all control characters to be sent to the terminal. +-- + +sideband..*:: + Apply the `sideband.*` option selectively to specific URLs. The + same URL matching logic applies as for `http..*` settings. diff --git a/sideband.c b/sideband.c index ea7c25211e..67e12eb21a 100644 --- a/sideband.c +++ b/sideband.c @@ -10,6 +10,7 @@ #include "help.h" #include "pkt-line.h" #include "write-or-die.h" +#include "urlmatch.h" struct keyword_entry { /* @@ -26,6 +27,87 @@ static struct keyword_entry keywords[] = { { "error", GIT_COLOR_BOLD_RED }, }; +static enum { + ALLOW_CONTROL_SEQUENCES_UNSET = -1, + ALLOW_NO_CONTROL_CHARACTERS = 0, + ALLOW_ANSI_COLOR_SEQUENCES = 1<<0, + ALLOW_ANSI_CURSOR_MOVEMENTS = 1<<1, + ALLOW_ANSI_ERASE = 1<<2, + ALLOW_DEFAULT_ANSI_SEQUENCES = ALLOW_ANSI_COLOR_SEQUENCES, + ALLOW_ALL_CONTROL_CHARACTERS = 1<<3, +} allow_control_characters = ALLOW_CONTROL_SEQUENCES_UNSET; + +static inline int skip_prefix_in_csv(const char *value, const char *prefix, + const char **out) +{ + if (!skip_prefix(value, prefix, &value) || + (*value && *value != ',')) + return 0; + *out = value + !!*value; + return 1; +} + +int sideband_allow_control_characters_config(const char *var, const char *value) +{ + switch (git_parse_maybe_bool(value)) { + case 0: + allow_control_characters = ALLOW_NO_CONTROL_CHARACTERS; + return 0; + case 1: + allow_control_characters = ALLOW_ALL_CONTROL_CHARACTERS; + return 0; + default: + break; + } + + allow_control_characters = ALLOW_NO_CONTROL_CHARACTERS; + while (*value) { + if (skip_prefix_in_csv(value, "default", &value)) + allow_control_characters |= ALLOW_DEFAULT_ANSI_SEQUENCES; + else if (skip_prefix_in_csv(value, "color", &value)) + allow_control_characters |= ALLOW_ANSI_COLOR_SEQUENCES; + else if (skip_prefix_in_csv(value, "cursor", &value)) + allow_control_characters |= ALLOW_ANSI_CURSOR_MOVEMENTS; + else if (skip_prefix_in_csv(value, "erase", &value)) + allow_control_characters |= ALLOW_ANSI_ERASE; + else if (skip_prefix_in_csv(value, "true", &value)) + allow_control_characters = ALLOW_ALL_CONTROL_CHARACTERS; + else if (skip_prefix_in_csv(value, "false", &value)) + allow_control_characters = ALLOW_NO_CONTROL_CHARACTERS; + else + warning(_("unrecognized value for '%s': '%s'"), var, value); + } + return 0; +} + +static int sideband_config_callback(const char *var, const char *value, + const struct config_context *ctx UNUSED, + void *data UNUSED) +{ + if (!strcmp(var, "sideband.allowcontrolcharacters")) + return sideband_allow_control_characters_config(var, value); + + return 0; +} + +void sideband_apply_url_config(const char *url) +{ + struct urlmatch_config config = URLMATCH_CONFIG_INIT; + char *normalized_url; + + if (!url) + BUG("must not call sideband_apply_url_config(NULL)"); + + config.section = "sideband"; + config.collect_fn = sideband_config_callback; + + normalized_url = url_normalize(url, &config.url); + repo_config(the_repository, urlmatch_config_entry, &config); + free(normalized_url); + string_list_clear(&config.vars, 1); + urlmatch_config_release(&config); +} + /* Returns a color setting (GIT_COLOR_NEVER, etc). */ static enum git_colorbool use_sideband_colors(void) { @@ -39,6 +121,16 @@ static enum git_colorbool use_sideband_colors(void) if (use_sideband_colors_cached != GIT_COLOR_UNKNOWN) return use_sideband_colors_cached; + if (allow_control_characters == ALLOW_CONTROL_SEQUENCES_UNSET) { + if (!repo_config_get_value(the_repository, + "sideband.allowcontrolcharacters", &value)) + sideband_allow_control_characters_config( + "sideband.allowcontrolcharacters", value); + + if (allow_control_characters == ALLOW_CONTROL_SEQUENCES_UNSET) + allow_control_characters = ALLOW_DEFAULT_ANSI_SEQUENCES; + } + if (!repo_config_get_string_tmp(the_repository, key, &value)) use_sideband_colors_cached = git_config_colorbool(key, value); else if (!repo_config_get_string_tmp(the_repository, "color.ui", &value)) @@ -66,6 +158,93 @@ 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_sequence(struct strbuf *dest, const char *src, int n) +{ + int i; + + /* + * Valid ANSI color sequences are of the form + * + * ESC [ [ [; ]*] m + * + * These are part of the Select Graphic Rendition sequences which + * contain more than just color sequences, for more details see + * https://en.wikipedia.org/wiki/ANSI_escape_code#SGR. + * + * The cursor movement sequences are: + * + * ESC [ n A - Cursor up n lines (CUU) + * ESC [ n B - Cursor down n lines (CUD) + * ESC [ n C - Cursor forward n columns (CUF) + * ESC [ n D - Cursor back n columns (CUB) + * ESC [ n E - Cursor next line, beginning (CNL) + * ESC [ n F - Cursor previous line, beginning (CPL) + * ESC [ n G - Cursor to column n (CHA) + * ESC [ n ; m H - Cursor position (row n, col m) (CUP) + * ESC [ n ; m f - Same as H (HVP) + * + * The sequences to erase characters are: + * + * + * ESC [ 0 J - Clear from cursor to end of screen (ED) + * ESC [ 1 J - Clear from cursor to beginning of screen (ED) + * ESC [ 2 J - Clear entire screen (ED) + * ESC [ 3 J - Clear entire screen + scrollback (ED) - xterm extension + * ESC [ 0 K - Clear from cursor to end of line (EL) + * ESC [ 1 K - Clear from cursor to beginning of line (EL) + * ESC [ 2 K - Clear entire line (EL) + * ESC [ n M - Delete n lines (DL) + * ESC [ n P - Delete n characters (DCH) + * ESC [ n X - Erase n characters (ECH) + * + * For a comprehensive list of common ANSI Escape sequences, see + * https://www.xfree86.org/current/ctlseqs.html + */ + + if (n < 3 || src[0] != '\x1b' || src[1] != '[') + return 0; + + for (i = 2; i < n; i++) { + if (((allow_control_characters & ALLOW_ANSI_COLOR_SEQUENCES) && + src[i] == 'm') || + ((allow_control_characters & ALLOW_ANSI_CURSOR_MOVEMENTS) && + strchr("ABCDEFGHf", src[i])) || + ((allow_control_characters & ALLOW_ANSI_ERASE) && + strchr("JKMPX", src[i]))) { + 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 (allow_control_characters != ALLOW_NO_CONTROL_CHARACTERS && + (i = handle_ansi_sequence(dest, src, n))) { + src += i; + n -= i; + } else { + strbuf_addch(dest, '^'); + strbuf_addch(dest, *src == 0x7f ? '?' : 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 @@ -81,7 +260,7 @@ 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; } @@ -114,7 +293,7 @@ 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/sideband.h b/sideband.h index 5a25331be5..d15fa4015f 100644 --- a/sideband.h +++ b/sideband.h @@ -30,4 +30,18 @@ int demultiplex_sideband(const char *me, int status, void send_sideband(int fd, int band, const char *data, ssize_t sz, int packet_max); +/* + * Apply sideband configuration for the given URL. This should be called + * when a transport is created to allow URL-specific configuration of + * sideband behavior (e.g., sideband..allowControlCharacters). + */ +void sideband_apply_url_config(const char *url); + +/* + * Parse and set the sideband allow control characters configuration. + * The var parameter should be the key name (without section prefix). + * Returns 0 if the variable was recognized and handled, non-zero otherwise. + */ +int sideband_allow_control_characters_config(const char *var, const char *value); + #endif diff --git a/t/t5409-colorize-remote-messages.sh b/t/t5409-colorize-remote-messages.sh index fa5de4500a..3010913bb1 100755 --- a/t/t5409-colorize-remote-messages.sh +++ b/t/t5409-colorize-remote-messages.sh @@ -98,4 +98,96 @@ 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_decode_csi() { + awk '{ + while (match($0, /\033/) != 0) { + printf "%sCSI ", substr($0, 1, RSTART-1); + $0 = substr($0, RSTART + RLENGTH, length($0) - RSTART - RLENGTH + 1); + } + print + }' +} + +test_expect_success 'control sequences in sideband allowed by default' ' + write_script .git/color-me-surprised <<-\EOF && + printf "error: \\033[31mcolor\\033[m\\033[Goverwrite\\033[Gerase\\033[K\\033?25l\\n" >&2 + exec "$@" + EOF + test_config_global uploadPack.packObjectsHook ./color-me-surprised && + test_commit need-at-least-one-commit-at-least && + + rm -rf throw-away && + git clone --no-local . throw-away 2>stderr && + test_decode_color color-decoded && + test_decode_csi decoded && + test_grep ! "CSI \\[K" decoded && + test_grep ! "CSI \\[G" decoded && + test_grep "\\^\\[?25l" decoded && + + rm -rf throw-away && + git -c sideband.allowControlCharacters=erase,cursor,color \ + clone --no-local . throw-away 2>stderr && + test_decode_color color-decoded && + test_decode_csi decoded && + test_grep "RED" decoded && + test_grep "CSI \\[K" decoded && + test_grep "CSI \\[G" decoded && + test_grep ! "\\^\\[\\[K" decoded && + test_grep ! "\\^\\[\\[G" decoded +' + +test_expect_success 'allow all control sequences for a specific URL' ' + write_script .git/eraser <<-\EOF && + printf "error: Ohai!\\r\\033[K" >&2 + exec "$@" + EOF + test_config_global uploadPack.packObjectsHook ./eraser && + test_commit one-more-please && + + rm -rf throw-away && + git clone --no-local . throw-away 2>stderr && + test_decode_color color-decoded && + test_decode_csi decoded && + test_grep ! "CSI \\[K" decoded && + test_grep "\\^\\[\\[K" decoded && + + rm -rf throw-away && + git -c "sideband.file://.allowControlCharacters=true" \ + clone --no-local "file://$PWD" throw-away 2>stderr && + test_decode_color color-decoded && + test_decode_csi decoded && + test_grep "CSI \\[K" decoded && + test_grep ! "\\^\\[\\[K" decoded +' + test_done diff --git a/transport.c b/transport.c index c5830e2b37..df3bd23de4 100644 --- a/transport.c +++ b/transport.c @@ -29,6 +29,7 @@ #include "object-name.h" #include "color.h" #include "bundle-uri.h" +#include "sideband.h" static enum git_colorbool transport_use_color = GIT_COLOR_UNKNOWN; static char transport_colors[][COLOR_MAXLEN] = { @@ -1246,6 +1247,8 @@ struct transport *transport_get(struct remote *remote, const char *url) ret->hash_algo = &hash_algos[GIT_HASH_SHA1_LEGACY]; + sideband_apply_url_config(ret->url); + return ret; }