| /* |
| * (C) 2011 by Harald Welte <laforge@gnumonks.org> |
| * (C) 2011 by Sylvain Munaut <tnt@246tNt.com> |
| * (C) 2014 by Nils O. SelÄsdal <noselasd@fiane.dyndns.org> |
| * |
| * All Rights Reserved |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| */ |
| |
| |
| #include <stdbool.h> |
| #include <string.h> |
| #include <stdint.h> |
| #include <errno.h> |
| #include <stdio.h> |
| #include <inttypes.h> |
| |
| #include <osmocom/core/utils.h> |
| #include <osmocom/core/bit64gen.h> |
| |
| |
| /*! \addtogroup utils |
| * @{ |
| * various utility routines |
| * |
| * \file utils.c */ |
| |
| static char namebuf[255]; |
| |
| /*! get human-readable string for given value |
| * \param[in] vs Array of value_string tuples |
| * \param[in] val Value to be converted |
| * \returns pointer to human-readable string |
| * |
| * If val is found in vs, the array's string entry is returned. Otherwise, an |
| * "unknown" string containing the actual value is composed in a static buffer |
| * that is reused across invocations. |
| */ |
| const char *get_value_string(const struct value_string *vs, uint32_t val) |
| { |
| const char *str = get_value_string_or_null(vs, val); |
| if (str) |
| return str; |
| |
| snprintf(namebuf, sizeof(namebuf), "unknown 0x%"PRIx32, val); |
| namebuf[sizeof(namebuf) - 1] = '\0'; |
| return namebuf; |
| } |
| |
| /*! get human-readable string or NULL for given value |
| * \param[in] vs Array of value_string tuples |
| * \param[in] val Value to be converted |
| * \returns pointer to human-readable string or NULL if val is not found |
| */ |
| const char *get_value_string_or_null(const struct value_string *vs, |
| uint32_t val) |
| { |
| int i; |
| |
| for (i = 0;; i++) { |
| if (vs[i].value == 0 && vs[i].str == NULL) |
| break; |
| if (vs[i].value == val) |
| return vs[i].str; |
| } |
| |
| return NULL; |
| } |
| |
| /*! get numeric value for given human-readable string |
| * \param[in] vs Array of value_string tuples |
| * \param[in] str human-readable string |
| * \returns numeric value (>0) or negative numer in case of error |
| */ |
| int get_string_value(const struct value_string *vs, const char *str) |
| { |
| int i; |
| |
| for (i = 0;; i++) { |
| if (vs[i].value == 0 && vs[i].str == NULL) |
| break; |
| if (!strcasecmp(vs[i].str, str)) |
| return vs[i].value; |
| } |
| return -EINVAL; |
| } |
| |
| /*! Convert BCD-encoded digit into printable character |
| * \param[in] bcd A single BCD-encoded digit |
| * \returns single printable character |
| */ |
| char osmo_bcd2char(uint8_t bcd) |
| { |
| if (bcd < 0xa) |
| return '0' + bcd; |
| else |
| return 'A' + (bcd - 0xa); |
| } |
| |
| /*! Convert number in ASCII to BCD value |
| * \param[in] c ASCII character |
| * \returns BCD encoded value of character |
| */ |
| uint8_t osmo_char2bcd(char c) |
| { |
| if (c >= '0' && c <= '9') |
| return c - 0x30; |
| else if (c >= 'A' && c <= 'F') |
| return 0xa + (c - 'A'); |
| else if (c >= 'a' && c <= 'f') |
| return 0xa + (c - 'a'); |
| else |
| return 0; |
| } |
| |
| /*! Parse a string containing hexadecimal digits |
| * \param[in] str string containing ASCII encoded hexadecimal digits |
| * \param[out] b output buffer |
| * \param[in] max_len maximum space in output buffer |
| * \returns number of parsed octets, or -1 on error |
| */ |
| int osmo_hexparse(const char *str, uint8_t *b, int max_len) |
| |
| { |
| char c; |
| uint8_t v; |
| const char *strpos; |
| unsigned int nibblepos = 0; |
| |
| memset(b, 0x00, max_len); |
| |
| for (strpos = str; (c = *strpos); strpos++) { |
| /* skip whitespace */ |
| if (c == ' ' || c == '\t' || c == '\n' || c == '\r') |
| continue; |
| |
| /* If the buffer is too small, error out */ |
| if (nibblepos >= (max_len << 1)) |
| return -1; |
| |
| if (c >= '0' && c <= '9') |
| v = c - '0'; |
| else if (c >= 'a' && c <= 'f') |
| v = 10 + (c - 'a'); |
| else if (c >= 'A' && c <= 'F') |
| v = 10 + (c - 'A'); |
| else |
| return -1; |
| |
| b[nibblepos >> 1] |= v << (nibblepos & 1 ? 0 : 4); |
| nibblepos ++; |
| } |
| |
| /* In case of uneven amount of digits, the last byte is not complete |
| * and that's an error. */ |
| if (nibblepos & 1) |
| return -1; |
| |
| return nibblepos >> 1; |
| } |
| |
| static char hexd_buff[4096]; |
| static const char hex_chars[] = "0123456789abcdef"; |
| |
| static char *_osmo_hexdump(const unsigned char *buf, int len, char *delim) |
| { |
| int i; |
| char *cur = hexd_buff; |
| |
| hexd_buff[0] = 0; |
| for (i = 0; i < len; i++) { |
| const char *delimp = delim; |
| int len_remain = sizeof(hexd_buff) - (cur - hexd_buff); |
| if (len_remain < 3) |
| break; |
| |
| *cur++ = hex_chars[buf[i] >> 4]; |
| *cur++ = hex_chars[buf[i] & 0xf]; |
| |
| while (len_remain > 1 && *delimp) { |
| *cur++ = *delimp++; |
| len_remain--; |
| } |
| |
| *cur = 0; |
| } |
| hexd_buff[sizeof(hexd_buff)-1] = 0; |
| return hexd_buff; |
| } |
| |
| /*! Convert a sequence of unpacked bits to ASCII string |
| * \param[in] bits A sequence of unpacked bits |
| * \param[in] len Length of bits |
| */ |
| char *osmo_ubit_dump(const uint8_t *bits, unsigned int len) |
| { |
| int i; |
| |
| if (len > sizeof(hexd_buff)-1) |
| len = sizeof(hexd_buff)-1; |
| memset(hexd_buff, 0, sizeof(hexd_buff)); |
| |
| for (i = 0; i < len; i++) { |
| char outch; |
| switch (bits[i]) { |
| case 0: |
| outch = '0'; |
| break; |
| case 0xff: |
| outch = '?'; |
| break; |
| case 1: |
| outch = '1'; |
| break; |
| default: |
| outch = 'E'; |
| break; |
| } |
| hexd_buff[i] = outch; |
| } |
| hexd_buff[sizeof(hexd_buff)-1] = 0; |
| return hexd_buff; |
| } |
| |
| /*! Convert binary sequence to hexadecimal ASCII string |
| * \param[in] buf pointer to sequence of bytes |
| * \param[in] len length of buf in number of bytes |
| * \returns pointer to zero-terminated string |
| * |
| * This function will print a sequence of bytes as hexadecimal numbers, |
| * adding one space character between each byte (e.g. "1a ef d9") |
| * |
| * The maximum size of the output buffer is 4096 bytes, i.e. the maximum |
| * number of input bytes that can be printed in one call is 1365! |
| */ |
| char *osmo_hexdump(const unsigned char *buf, int len) |
| { |
| return _osmo_hexdump(buf, len, " "); |
| } |
| |
| /*! Convert binary sequence to hexadecimal ASCII string |
| * \param[in] buf pointer to sequence of bytes |
| * \param[in] len length of buf in number of bytes |
| * \returns pointer to zero-terminated string |
| * |
| * This function will print a sequence of bytes as hexadecimal numbers, |
| * without any space character between each byte (e.g. "1aefd9") |
| * |
| * The maximum size of the output buffer is 4096 bytes, i.e. the maximum |
| * number of input bytes that can be printed in one call is 2048! |
| */ |
| char *osmo_hexdump_nospc(const unsigned char *buf, int len) |
| { |
| return _osmo_hexdump(buf, len, ""); |
| } |
| |
| /* Compat with previous typo to preserve abi */ |
| char *osmo_osmo_hexdump_nospc(const unsigned char *buf, int len) |
| #if defined(__MACH__) && defined(__APPLE__) |
| ; |
| #else |
| __attribute__((weak, alias("osmo_hexdump_nospc"))); |
| #endif |
| |
| #include "../config.h" |
| #ifdef HAVE_CTYPE_H |
| #include <ctype.h> |
| /*! Convert an entire string to lower case |
| * \param[out] out output string, caller-allocated |
| * \param[in] in input string |
| */ |
| void osmo_str2lower(char *out, const char *in) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < strlen(in); i++) |
| out[i] = tolower((const unsigned char)in[i]); |
| out[strlen(in)] = '\0'; |
| } |
| |
| /*! Convert an entire string to upper case |
| * \param[out] out output string, caller-allocated |
| * \param[in] in input string |
| */ |
| void osmo_str2upper(char *out, const char *in) |
| { |
| unsigned int i; |
| |
| for (i = 0; i < strlen(in); i++) |
| out[i] = toupper((const unsigned char)in[i]); |
| out[strlen(in)] = '\0'; |
| } |
| #endif /* HAVE_CTYPE_H */ |
| |
| /*! Wishful thinking to generate a constant time compare |
| * \param[in] exp Expected data |
| * \param[in] rel Comparison value |
| * \param[in] count Number of bytes to compare |
| * \returns 1 in case \a exp equals \a rel; zero otherwise |
| * |
| * Compare count bytes of exp to rel. Return 0 if they are identical, 1 |
| * otherwise. Do not return a mismatch on the first mismatching byte, |
| * but always compare all bytes, regardless. The idea is that the amount of |
| * matching bytes cannot be inferred from the time the comparison took. */ |
| int osmo_constant_time_cmp(const uint8_t *exp, const uint8_t *rel, const int count) |
| { |
| int x = 0, i; |
| |
| for (i = 0; i < count; ++i) |
| x |= exp[i] ^ rel[i]; |
| |
| /* if x is zero, all data was identical */ |
| return x? 1 : 0; |
| } |
| |
| /*! Generic retrieval of 1..8 bytes as big-endian uint64_t |
| * \param[in] data Input data as byte-array |
| * \param[in] data_len Length of \a data in octets |
| * \returns uint64_t of \a data interpreted as big-endian |
| * |
| * This is like osmo_load64be_ext, except that if data_len is less than |
| * sizeof(uint64_t), the data is interpreted as the least significant bytes |
| * (osmo_load64be_ext loads them as the most significant bytes into the |
| * returned uint64_t). In this way, any integer size up to 64 bits can be |
| * decoded conveniently by using sizeof(), without the need to call specific |
| * numbered functions (osmo_load16, 32, ...). */ |
| uint64_t osmo_decode_big_endian(const uint8_t *data, size_t data_len) |
| { |
| uint64_t value = 0; |
| |
| while (data_len > 0) { |
| value = (value << 8) + *data; |
| data += 1; |
| data_len -= 1; |
| } |
| |
| return value; |
| } |
| |
| /*! Generic big-endian encoding of big endian number up to 64bit |
| * \param[in] value unsigned integer value to be stored |
| * \param[in] data_len number of octets |
| * \returns static buffer containing big-endian stored value |
| * |
| * This is like osmo_store64be_ext, except that this returns a static buffer of |
| * the result (for convenience, but not threadsafe). If data_len is less than |
| * sizeof(uint64_t), only the least significant bytes of value are encoded. */ |
| uint8_t *osmo_encode_big_endian(uint64_t value, size_t data_len) |
| { |
| static uint8_t buf[sizeof(uint64_t)]; |
| OSMO_ASSERT(data_len <= ARRAY_SIZE(buf)); |
| osmo_store64be_ext(value, buf, data_len); |
| return buf; |
| } |
| |
| /*! Copy a C-string into a sized buffer |
| * \param[in] src source string |
| * \param[out] dst destination string |
| * \param[in] siz size of the \a dst buffer |
| * \returns length of \a src |
| * |
| * Copy at most \a siz bytes from \a src to \a dst, ensuring that the result is |
| * NUL terminated. The NUL character is included in \a siz, i.e. passing the |
| * actual sizeof(*dst) is correct. |
| */ |
| size_t osmo_strlcpy(char *dst, const char *src, size_t siz) |
| { |
| size_t ret = src ? strlen(src) : 0; |
| |
| if (siz) { |
| size_t len = (ret >= siz) ? siz - 1 : ret; |
| if (src) |
| memcpy(dst, src, len); |
| dst[len] = '\0'; |
| } |
| return ret; |
| } |
| |
| /*! Validate that a given string is a hex string within given size limits. |
| * Note that each hex digit amounts to a nibble, so if checking for a hex |
| * string to result in N bytes, pass amount of digits as 2*N. |
| * \param str A nul-terminated string to validate, or NULL. |
| * \param min_digits least permitted amount of digits. |
| * \param max_digits most permitted amount of digits. |
| * \param require_even if true, require an even amount of digits. |
| * \returns true when the hex_str contains only hexadecimal digits (no |
| * whitespace) and matches the requested length; also true |
| * when min_digits <= 0 and str is NULL. |
| */ |
| bool osmo_is_hexstr(const char *str, int min_digits, int max_digits, |
| bool require_even) |
| { |
| int len; |
| /* Use unsigned char * to avoid a compiler warning of |
| * "error: array subscript has type 'char' [-Werror=char-subscripts]" */ |
| const unsigned char *pos = (const unsigned char*)str; |
| if (!pos) |
| return min_digits < 1; |
| for (len = 0; *pos && len < max_digits; len++, pos++) |
| if (!isxdigit(*pos)) |
| return false; |
| if (len < min_digits) |
| return false; |
| /* With not too many digits, we should have reached *str == nul */ |
| if (*pos) |
| return false; |
| if (require_even && (len & 1)) |
| return false; |
| |
| return true; |
| } |
| |
| /*! Determine if a given identifier is valid, i.e. doesn't contain illegal chars |
| * \param[in] str String to validate |
| * \param[in] sep_chars Permitted separation characters between identifiers. |
| * \returns true in case \a str contains only valid identifiers and sep_chars, false otherwise |
| */ |
| bool osmo_separated_identifiers_valid(const char *str, const char *sep_chars) |
| { |
| /* characters that are illegal in names */ |
| static const char illegal_chars[] = "., {}[]()<>|~\\^`'\"?=;/+*&%$#!"; |
| unsigned int i; |
| size_t len; |
| |
| /* an empty string is not a valid identifier */ |
| if (!str || (len = strlen(str)) == 0) |
| return false; |
| |
| for (i = 0; i < len; i++) { |
| if (sep_chars && strchr(sep_chars, str[i])) |
| continue; |
| /* check for 7-bit ASCII */ |
| if (str[i] & 0x80) |
| return false; |
| if (!isprint((int)str[i])) |
| return false; |
| /* check for some explicit reserved control characters */ |
| if (strchr(illegal_chars, str[i])) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| /*! Determine if a given identifier is valid, i.e. doesn't contain illegal chars |
| * \param[in] str String to validate |
| * \returns true in case \a str contains valid identifier, false otherwise |
| */ |
| bool osmo_identifier_valid(const char *str) |
| { |
| return osmo_separated_identifiers_valid(str, NULL); |
| } |
| |
| /*! Return the string with all non-printable characters escaped. |
| * \param[in] str A string that may contain any characters. |
| * \param[in] len Pass -1 to print until nul char, or >= 0 to force a length. |
| * \param[inout] buf string buffer to write escaped characters to. |
| * \param[in] bufsize size of \a buf. |
| * \returns buf containing an escaped representation, possibly truncated, or str itself. |
| */ |
| const char *osmo_escape_str_buf(const char *str, int in_len, char *buf, size_t bufsize) |
| { |
| int in_pos = 0; |
| int next_unprintable = 0; |
| int out_pos = 0; |
| char *out = buf; |
| /* -1 to leave space for a final \0 */ |
| int out_len = bufsize-1; |
| |
| if (!str) |
| return "(null)"; |
| |
| if (in_len < 0) |
| in_len = strlen(str); |
| |
| while (in_pos < in_len) { |
| for (next_unprintable = in_pos; |
| next_unprintable < in_len && isprint((int)str[next_unprintable]) |
| && str[next_unprintable] != '"' |
| && str[next_unprintable] != '\\'; |
| next_unprintable++); |
| |
| if (next_unprintable == in_len |
| && in_pos == 0) |
| return str; |
| |
| while (in_pos < next_unprintable && out_pos < out_len) |
| out[out_pos++] = str[in_pos++]; |
| |
| if (out_pos == out_len || in_pos == in_len) |
| goto done; |
| |
| switch (str[next_unprintable]) { |
| #define BACKSLASH_CASE(c, repr) \ |
| case c: \ |
| if (out_pos > out_len-2) \ |
| goto done; \ |
| out[out_pos++] = '\\'; \ |
| out[out_pos++] = repr; \ |
| break |
| |
| BACKSLASH_CASE('\n', 'n'); |
| BACKSLASH_CASE('\r', 'r'); |
| BACKSLASH_CASE('\t', 't'); |
| BACKSLASH_CASE('\0', '0'); |
| BACKSLASH_CASE('\a', 'a'); |
| BACKSLASH_CASE('\b', 'b'); |
| BACKSLASH_CASE('\v', 'v'); |
| BACKSLASH_CASE('\f', 'f'); |
| BACKSLASH_CASE('\\', '\\'); |
| BACKSLASH_CASE('"', '"'); |
| #undef BACKSLASH_CASE |
| |
| default: |
| out_pos += snprintf(&out[out_pos], out_len - out_pos, "\\%u", (unsigned char)str[in_pos]); |
| if (out_pos > out_len) { |
| out_pos = out_len; |
| goto done; |
| } |
| break; |
| } |
| in_pos ++; |
| } |
| |
| done: |
| out[out_pos] = '\0'; |
| return out; |
| } |
| |
| /*! Return the string with all non-printable characters escaped. |
| * Call osmo_escape_str_buf() with a static buffer. |
| * \param[in] str A string that may contain any characters. |
| * \param[in] len Pass -1 to print until nul char, or >= 0 to force a length. |
| * \returns buf containing an escaped representation, possibly truncated, or str itself. |
| */ |
| const char *osmo_escape_str(const char *str, int in_len) |
| { |
| return osmo_escape_str_buf(str, in_len, namebuf, sizeof(namebuf)); |
| } |
| |
| /*! Like osmo_escape_str(), but returns double-quotes around a string, or "NULL" for a NULL string. |
| * This allows passing any char* value and get its C representation as string. |
| * \param[in] str A string that may contain any characters. |
| * \param[in] len Pass -1 to print until nul char, or >= 0 to force a length. |
| * \returns buf containing an escaped representation, possibly truncated, or str itself. |
| */ |
| const char *osmo_quote_str_buf(const char *str, int in_len, char *buf, size_t bufsize) |
| { |
| const char *res; |
| int l; |
| if (!str) |
| return "NULL"; |
| if (bufsize < 3) |
| return "<buf-too-small>"; |
| buf[0] = '"'; |
| res = osmo_escape_str_buf(str, in_len, buf + 1, bufsize - 2); |
| /* if osmo_escape_str_buf() returned the str itself, we need to copy it to buf to be able to |
| * quote it. */ |
| if (res == str) { |
| /* max_len = bufsize - two quotes - nul term */ |
| int max_len = bufsize - 2 - 1; |
| if (in_len >= 0) |
| max_len = OSMO_MIN(in_len, max_len); |
| /* It is not allowed to pass unterminated strings into osmo_strlcpy() :/ */ |
| strncpy(buf + 1, str, max_len); |
| buf[1 + max_len] = '\0'; |
| } |
| l = strlen(buf); |
| buf[l] = '"'; |
| buf[l+1] = '\0'; /* both osmo_escape_str_buf() and max_len above ensure room for '\0' */ |
| return buf; |
| } |
| |
| const char *osmo_quote_str(const char *str, int in_len) |
| { |
| return osmo_quote_str_buf(str, in_len, namebuf, sizeof(namebuf)); |
| } |
| |
| /*! perform an integer square root operation on unsigned 32bit integer. |
| * This implementation is taken from "Hacker's Delight" Figure 11-1 "Integer square root, Newton's |
| * method", which can also be found at http://www.hackersdelight.org/hdcodetxt/isqrt.c.txt */ |
| uint32_t osmo_isqrt32(uint32_t x) |
| { |
| uint32_t x1; |
| int s, g0, g1; |
| |
| if (x <= 1) |
| return x; |
| |
| s = 1; |
| x1 = x - 1; |
| if (x1 > 0xffff) { |
| s = s + 8; |
| x1 = x1 >> 16; |
| } |
| if (x1 > 0xff) { |
| s = s + 4; |
| x1 = x1 >> 8; |
| } |
| if (x1 > 0xf) { |
| s = s + 2; |
| x1 = x1 >> 4; |
| } |
| if (x1 > 0x3) { |
| s = s + 1; |
| } |
| |
| g0 = 1 << s; /* g0 = 2**s */ |
| g1 = (g0 + (x >> s)) >> 1; /* g1 = (g0 + x/g0)/2 */ |
| |
| /* converges after four to five divisions for arguments up to 16,785,407 */ |
| while (g1 < g0) { |
| g0 = g1; |
| g1 = (g0 + (x/g0)) >> 1; |
| } |
| return g0; |
| } |
| |
| /*! @} */ |