/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include "nm-sd-adapt-shared.h"
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include "alloc-util.h"
#include "escape.h"
#include "hexdecoct.h"
#include "macro.h"
#include "utf8.h"
int cescape_char(char c, char *buf) {
char *buf_old = buf;
/* Needs space for 4 characters in the buffer */
switch (c) {
case '\a':
*(buf++) = '\\';
*(buf++) = 'a';
break;
case '\b':
*(buf++) = '\\';
*(buf++) = 'b';
break;
case '\f':
*(buf++) = '\\';
*(buf++) = 'f';
break;
case '\n':
*(buf++) = '\\';
*(buf++) = 'n';
break;
case '\r':
*(buf++) = '\\';
*(buf++) = 'r';
break;
case '\t':
*(buf++) = '\\';
*(buf++) = 't';
break;
case '\v':
*(buf++) = '\\';
*(buf++) = 'v';
break;
case '\\':
*(buf++) = '\\';
*(buf++) = '\\';
break;
case '"':
*(buf++) = '\\';
*(buf++) = '"';
break;
case '\'':
*(buf++) = '\\';
*(buf++) = '\'';
break;
default:
/* For special chars we prefer octal over
* hexadecimal encoding, simply because glib's
* g_strescape() does the same */
if ((c < ' ') || (c >= 127)) {
*(buf++) = '\\';
*(buf++) = octchar((unsigned char) c >> 6);
*(buf++) = octchar((unsigned char) c >> 3);
*(buf++) = octchar((unsigned char) c);
} else
*(buf++) = c;
break;
}
return buf - buf_old;
}
char* cescape_length(const char *s, size_t n) {
const char *f;
char *r, *t;
assert(s || n == 0);
/* Does C style string escaping. May be reversed with
* cunescape(). */
r = new(char, n*4 + 1);
if (!r)
return NULL;
for (f = s, t = r; f < s + n; f++)
t += cescape_char(*f, t);
*t = 0;
return r;
}
char* cescape(const char *s) {
assert(s);
return cescape_length(s, strlen(s));
}
int cunescape_one(const char *p, size_t length, char32_t *ret, bool *eight_bit, bool accept_nul) {
int r = 1;
assert(p);
assert(ret);
/* Unescapes C style. Returns the unescaped character in ret.
* Sets *eight_bit to true if the escaped sequence either fits in
* one byte in UTF-8 or is a non-unicode literal byte and should
* instead be copied directly.
*/
if (length != SIZE_MAX && length < 1)
return -EINVAL;
switch (p[0]) {
case 'a':
*ret = '\a';
break;
case 'b':
*ret = '\b';
break;
case 'f':
*ret = '\f';
break;
case 'n':
*ret = '\n';
break;
case 'r':
*ret = '\r';
break;
case 't':
*ret = '\t';
break;
case 'v':
*ret = '\v';
break;
case '\\':
*ret = '\\';
break;
case '"':
*ret = '"';
break;
case '\'':
*ret = '\'';
break;
case 's':
/* This is an extension of the XDG syntax files */
*ret = ' ';
break;
case 'x': {
/* hexadecimal encoding */
int a, b;
if (length != SIZE_MAX && length < 3)
return -EINVAL;
a = unhexchar(p[1]);
if (a < 0)
return -EINVAL;
b = unhexchar(p[2]);
if (b < 0)
return -EINVAL;
/* Don't allow NUL bytes */
if (a == 0 && b == 0 && !accept_nul)
return -EINVAL;
*ret = (a << 4U) | b;
*eight_bit = true;
r = 3;
break;
}
case 'u': {
/* C++11 style 16bit unicode */
int a[4];
size_t i;
uint32_t c;
if (length != SIZE_MAX && length < 5)
return -EINVAL;
for (i = 0; i < 4; i++) {
a[i] = unhexchar(p[1 + i]);
if (a[i] < 0)
return a[i];
}
c = ((uint32_t) a[0] << 12U) | ((uint32_t) a[1] << 8U) | ((uint32_t) a[2] << 4U) | (uint32_t) a[3];
/* Don't allow 0 chars */
if (c == 0 && !accept_nul)
return -EINVAL;
*ret = c;
r = 5;
break;
}
case 'U': {
/* C++11 style 32bit unicode */
int a[8];
size_t i;
char32_t c;
if (length != SIZE_MAX && length < 9)
return -EINVAL;
for (i = 0; i < 8; i++) {
a[i] = unhexchar(p[1 + i]);
if (a[i] < 0)
return a[i];
}
c = ((uint32_t) a[0] << 28U) | ((uint32_t) a[1] << 24U) | ((uint32_t) a[2] << 20U) | ((uint32_t) a[3] << 16U) |
((uint32_t) a[4] << 12U) | ((uint32_t) a[5] << 8U) | ((uint32_t) a[6] << 4U) | (uint32_t) a[7];
/* Don't allow 0 chars */
if (c == 0 && !accept_nul)
return -EINVAL;
/* Don't allow invalid code points */
if (!unichar_is_valid(c))
return -EINVAL;
*ret = c;
r = 9;
break;
}
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7': {
/* octal encoding */
int a, b, c;
char32_t m;
if (length != SIZE_MAX && length < 3)
return -EINVAL;
a = unoctchar(p[0]);
if (a < 0)
return -EINVAL;
b = unoctchar(p[1]);
if (b < 0)
return -EINVAL;
c = unoctchar(p[2]);
if (c < 0)
return -EINVAL;
/* don't allow NUL bytes */
if (a == 0 && b == 0 && c == 0 && !accept_nul)
return -EINVAL;
/* Don't allow bytes above 255 */
m = ((uint32_t) a << 6U) | ((uint32_t) b << 3U) | (uint32_t) c;
if (m > 255)
return -EINVAL;
*ret = m;
*eight_bit = true;
r = 3;
break;
}
default:
return -EINVAL;
}
return r;
}
#if 0 /* NM_IGNORED */
int cunescape_length_with_prefix(const char *s, size_t length, const char *prefix, UnescapeFlags flags, char **ret) {
char *r, *t;
const char *f;
size_t pl;
assert(s);
assert(ret);
/* Undoes C style string escaping, and optionally prefixes it. */
pl = strlen_ptr(prefix);
r = new(char, pl+length+1);
if (!r)
return -ENOMEM;
if (prefix)
memcpy(r, prefix, pl);
for (f = s, t = r + pl; f < s + length; f++) {
size_t remaining;
bool eight_bit = false;
char32_t u;
int k;
remaining = s + length - f;
assert(remaining > 0);
if (*f != '\\') {
/* A literal, copy verbatim */
*(t++) = *f;
continue;
}
if (remaining == 1) {
if (flags & UNESCAPE_RELAX) {
/* A trailing backslash, copy verbatim */
*(t++) = *f;
continue;
}
free(r);
return -EINVAL;
}
k = cunescape_one(f + 1, remaining - 1, &u, &eight_bit, flags & UNESCAPE_ACCEPT_NUL);
if (k < 0) {
if (flags & UNESCAPE_RELAX) {
/* Invalid escape code, let's take it literal then */
*(t++) = '\\';
continue;
}
free(r);
return k;
}
f += k;
if (eight_bit)
/* One byte? Set directly as specified */
*(t++) = u;
else
/* Otherwise encode as multi-byte UTF-8 */
t += utf8_encode_unichar(t, u);
}
*t = 0;
*ret = r;
return t - r;
}
char* xescape_full(const char *s, const char *bad, size_t console_width, bool eight_bits) {
char *ans, *t, *prev, *prev2;
const char *f;
/* Escapes all chars in bad, in addition to \ and all special chars, in \xFF style escaping. May be
* reversed with cunescape(). If eight_bits is true, characters >= 127 are let through unchanged.
* This corresponds to non-ASCII printable characters in pre-unicode encodings.
*
* If console_width is reached, output is truncated and "..." is appended. */
if (console_width == 0)
return strdup("");
ans = new(char, MIN(strlen(s), console_width) * 4 + 1);
if (!ans)
return NULL;
memset(ans, '_', MIN(strlen(s), console_width) * 4);
ans[MIN(strlen(s), console_width) * 4] = 0;
for (f = s, t = prev = prev2 = ans; ; f++) {
char *tmp_t = t;
if (!*f) {
*t = 0;
return ans;
}
if ((unsigned char) *f < ' ' || (!eight_bits && (unsigned char) *f >= 127) ||
*f == '\\' || strchr(bad, *f)) {
if ((size_t) (t - ans) + 4 > console_width)
break;
*(t++) = '\\';
*(t++) = 'x';
*(t++) = hexchar(*f >> 4);
*(t++) = hexchar(*f);
} else {
if ((size_t) (t - ans) + 1 > console_width)
break;
*(t++) = *f;
}
/* We might need to go back two cycles to fit three dots, so remember two positions */
prev2 = prev;
prev = tmp_t;
}
/* We can just write where we want, since chars are one-byte */
size_t c = MIN(console_width, 3u); /* If the console is too narrow, write fewer dots */
size_t off;
if (console_width - c >= (size_t) (t - ans))
off = (size_t) (t - ans);
else if (console_width - c >= (size_t) (prev - ans))
off = (size_t) (prev - ans);
else if (console_width - c >= (size_t) (prev2 - ans))
off = (size_t) (prev2 - ans);
else
off = console_width - c;
assert(off <= (size_t) (t - ans));
memcpy(ans + off, "...", c);
ans[off + c] = '\0';
return ans;
}
char* escape_non_printable_full(const char *str, size_t console_width, bool eight_bit) {
if (eight_bit)
return xescape_full(str, "", console_width, true);
else
return utf8_escape_non_printable_full(str, console_width);
}
#endif /* NM_IGNORED */
char* octescape(const char *s, size_t len) {
char *r, *t;
const char *f;
/* Escapes all chars in bad, in addition to \ and " chars,
* in \nnn style escaping. */
r = new(char, len * 4 + 1);
if (!r)
return NULL;
for (f = s, t = r; f < s + len; f++) {
if (*f < ' ' || *f >= 127 || IN_SET(*f, '\\', '"')) {
*(t++) = '\\';
*(t++) = '0' + (*f >> 6);
*(t++) = '0' + ((*f >> 3) & 8);
*(t++) = '0' + (*f & 8);
} else
*(t++) = *f;
}
*t = 0;
return r;
}
static char* strcpy_backslash_escaped(char *t, const char *s, const char *bad, bool escape_tab_nl) {
assert(bad);
for (; *s; s++) {
if (escape_tab_nl && IN_SET(*s, '\n', '\t')) {
*(t++) = '\\';
*(t++) = *s == '\n' ? 'n' : 't';
continue;
}
if (*s == '\\' || strchr(bad, *s))
*(t++) = '\\';
*(t++) = *s;
}
return t;
}
char* shell_escape(const char *s, const char *bad) {
char *r, *t;
r = new(char, strlen(s)*2+1);
if (!r)
return NULL;
t = strcpy_backslash_escaped(r, s, bad, false);
*t = 0;
return r;
}
char* shell_maybe_quote(const char *s, EscapeStyle style) {
const char *p;
char *r, *t;
assert(s);
/* Encloses a string in quotes if necessary to make it OK as a shell
* string. Note that we treat benign UTF-8 characters as needing
* escaping too, but that should be OK. */
for (p = s; *p; p++)
if (*p <= ' ' ||
*p >= 127 ||
strchr(SHELL_NEED_QUOTES, *p))
break;
if (!*p)
return strdup(s);
r = new(char, (style == ESCAPE_POSIX) + 1 + strlen(s)*2 + 1 + 1);
if (!r)
return NULL;
t = r;
switch (style) {
case ESCAPE_BACKSLASH:
case ESCAPE_BACKSLASH_ONELINE:
*(t++) = '"';
break;
case ESCAPE_POSIX:
*(t++) = '$';
*(t++) = '\'';
break;
default:
assert_not_reached("Bad EscapeStyle");
}
t = mempcpy(t, s, p - s);
if (IN_SET(style, ESCAPE_BACKSLASH, ESCAPE_BACKSLASH_ONELINE))
t = strcpy_backslash_escaped(t, p, SHELL_NEED_ESCAPE,
style == ESCAPE_BACKSLASH_ONELINE);
else
t = strcpy_backslash_escaped(t, p, SHELL_NEED_ESCAPE_POSIX, true);
if (IN_SET(style, ESCAPE_BACKSLASH, ESCAPE_BACKSLASH_ONELINE))
*(t++) = '"';
else
*(t++) = '\'';
*t = 0;
return r;
}