mirror of https://github.com/ntop/n2n.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
535 lines
14 KiB
535 lines
14 KiB
/**
|
|
* (C) 2007-20 - ntop.org and contributors
|
|
*
|
|
* 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 3 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 see see <http://www.gnu.org/licenses/>
|
|
*
|
|
*/
|
|
|
|
// taken from https://github.com/kokke/tiny-regex-c
|
|
// under Unlicense as of August 4, 2020
|
|
|
|
/*
|
|
*
|
|
* Mini regex-module inspired by Rob Pike's regex code described in:
|
|
*
|
|
* http://www.cs.princeton.edu/courses/archive/spr09/cos333/beautiful.html
|
|
*
|
|
*
|
|
*
|
|
* Supports:
|
|
* ---------
|
|
* '.' Dot, matches any character
|
|
* '^' Start anchor, matches beginning of string -- NOTE: currently disabled (checking for full matches anyway)
|
|
* '$' End anchor, matches end of string -- NOTE: currently disabled (checking for full matches anyway)
|
|
* '*' Asterisk, match zero or more (greedy)
|
|
* '+' Plus, match one or more (greedy)
|
|
* '?' Question, match zero or one (non-greedy)
|
|
* '[abc]' Character class, match if one of {'a', 'b', 'c'}
|
|
* '[^abc]' Inverted class, match if NOT one of {'a', 'b', 'c'} -- NOTE: feature is currently broken!
|
|
* '[a-zA-Z]' Character ranges, the character set of the ranges { a-z | A-Z }
|
|
* '\s' Whitespace, \t \f \r \n \v and spaces
|
|
* '\S' Non-whitespace
|
|
* '\w' Alphanumeric, [a-zA-Z0-9_]
|
|
* '\W' Non-alphanumeric
|
|
* '\d' Digits, [0-9]
|
|
* '\D' Non-digits
|
|
*
|
|
*
|
|
*/
|
|
|
|
|
|
#include "n2n_regex.h"
|
|
#include "n2n.h"
|
|
|
|
/* Definitions: */
|
|
|
|
#define MAX_REGEXP_OBJECTS 30 /* Max number of regex symbols in expression. */
|
|
#define MAX_CHAR_CLASS_LEN 40 /* Max length of character-class buffer in. */
|
|
|
|
|
|
enum { UNUSED, DOT, BEGIN, END, QUESTIONMARK, STAR, PLUS, CHAR, CHAR_CLASS, INV_CHAR_CLASS, DIGIT, NOT_DIGIT, ALPHA, NOT_ALPHA, WHITESPACE, NOT_WHITESPACE, /* BRANCH */ };
|
|
|
|
typedef struct regex_t
|
|
{
|
|
unsigned char type; /* CHAR, STAR, etc. */
|
|
union
|
|
{
|
|
unsigned char ch; /* the character itself */
|
|
unsigned char* ccl; /* OR a pointer to characters in class */
|
|
};
|
|
} regex_t;
|
|
|
|
|
|
|
|
/* Private function declarations: */
|
|
static int matchpattern(regex_t* pattern, const char* text, int* matchlength);
|
|
static int matchcharclass(char c, const char* str);
|
|
static int matchstar(regex_t p, regex_t* pattern, const char* text, int* matchlength);
|
|
static int matchplus(regex_t p, regex_t* pattern, const char* text, int* matchlength);
|
|
static int matchone(regex_t p, char c);
|
|
static int matchdigit(char c);
|
|
static int matchalpha(char c);
|
|
static int matchwhitespace(char c);
|
|
static int matchmetachar(char c, const char* str);
|
|
static int matchrange(char c, const char* str);
|
|
static int matchdot(char c);
|
|
static int ismetachar(char c);
|
|
|
|
|
|
|
|
/* Public functions: */
|
|
int re_match(const char* pattern, const char* text, int* matchlength)
|
|
{
|
|
re_t re_p; /* pointer to (to be created) copy of compiled regex */
|
|
int ret = -1;
|
|
|
|
re_p = re_compile (pattern);
|
|
ret = re_matchp(re_p, text, matchlength);
|
|
free(re_p);
|
|
|
|
return(ret);
|
|
}
|
|
|
|
int re_matchp(re_t pattern, const char* text, int* matchlength)
|
|
{
|
|
*matchlength = 0;
|
|
if (pattern != 0)
|
|
{
|
|
if (pattern[0].type == BEGIN)
|
|
{
|
|
return ((matchpattern(&pattern[1], text, matchlength)) ? 0 : -1);
|
|
}
|
|
else
|
|
{
|
|
int idx = -1;
|
|
|
|
do
|
|
{
|
|
idx += 1;
|
|
|
|
if (matchpattern(pattern, text, matchlength))
|
|
{
|
|
if (text[0] == '\0')
|
|
return -1;
|
|
|
|
return idx;
|
|
}
|
|
}
|
|
while (*text++ != '\0');
|
|
}
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
re_t re_compile(const char* pattern)
|
|
{
|
|
/* The sizes of the two static arrays below substantiates the static RAM usage of this module.
|
|
MAX_REGEXP_OBJECTS is the max number of symbols in the expression.
|
|
MAX_CHAR_CLASS_LEN determines the size of buffer for chars in all char-classes in the expression. */
|
|
static regex_t re_compiled[MAX_REGEXP_OBJECTS];
|
|
re_t re_p; /* pointer to (to be created) copy of compiled regex in re_compiled */
|
|
|
|
static unsigned char ccl_buf[MAX_CHAR_CLASS_LEN];
|
|
int ccl_bufidx = 1;
|
|
|
|
char c; /* current char in pattern */
|
|
int i = 0; /* index into pattern */
|
|
int j = 0; /* index into re_compiled */
|
|
|
|
while (pattern[i] != '\0' && (j+1 < MAX_REGEXP_OBJECTS))
|
|
{
|
|
c = pattern[i];
|
|
|
|
switch (c)
|
|
{
|
|
/* Meta-characters: */
|
|
// case '^': { re_compiled[j].type = BEGIN; } break; <-- disabled (always full matches)
|
|
// case '$': { re_compiled[j].type = END; } break; <-- disabled (always full matches)
|
|
case '.': { re_compiled[j].type = DOT; } break;
|
|
case '*': { re_compiled[j].type = STAR; } break;
|
|
case '+': { re_compiled[j].type = PLUS; } break;
|
|
case '?': { re_compiled[j].type = QUESTIONMARK; } break;
|
|
/* case '|': { re_compiled[j].type = BRANCH; } break; <-- not working properly */
|
|
|
|
/* Escaped character-classes (\s \w ...): */
|
|
case '\\':
|
|
{
|
|
if (pattern[i+1] != '\0')
|
|
{
|
|
/* Skip the escape-char '\\' */
|
|
i += 1;
|
|
/* ... and check the next */
|
|
switch (pattern[i])
|
|
{
|
|
/* Meta-character: */
|
|
case 'd': { re_compiled[j].type = DIGIT; } break;
|
|
case 'D': { re_compiled[j].type = NOT_DIGIT; } break;
|
|
case 'w': { re_compiled[j].type = ALPHA; } break;
|
|
case 'W': { re_compiled[j].type = NOT_ALPHA; } break;
|
|
case 's': { re_compiled[j].type = WHITESPACE; } break;
|
|
case 'S': { re_compiled[j].type = NOT_WHITESPACE; } break;
|
|
|
|
/* Escaped character, e.g. '.' */
|
|
default:
|
|
{
|
|
re_compiled[j].type = CHAR;
|
|
re_compiled[j].ch = pattern[i];
|
|
} break;
|
|
}
|
|
}
|
|
/* '\\' as last char in pattern -> invalid regular expression. */
|
|
/*
|
|
else
|
|
{
|
|
re_compiled[j].type = CHAR;
|
|
re_compiled[j].ch = pattern[i];
|
|
}
|
|
*/
|
|
} break;
|
|
|
|
/* Character class: */
|
|
case '[':
|
|
{
|
|
/* Remember where the char-buffer starts. */
|
|
int buf_begin = ccl_bufidx;
|
|
|
|
/* Look-ahead to determine if negated */
|
|
if (pattern[i+1] == '^')
|
|
{
|
|
re_compiled[j].type = INV_CHAR_CLASS;
|
|
i += 1; /* Increment i to avoid including '^' in the char-buffer */
|
|
}
|
|
else
|
|
{
|
|
re_compiled[j].type = CHAR_CLASS;
|
|
}
|
|
|
|
/* Copy characters inside [..] to buffer */
|
|
while ( (pattern[++i] != ']')
|
|
&& (pattern[i] != '\0')) /* Missing ] */
|
|
{
|
|
if (pattern[i] == '\\')
|
|
{
|
|
if (ccl_bufidx >= MAX_CHAR_CLASS_LEN - 1)
|
|
{
|
|
//fputs("exceeded internal buffer!\n", stderr);
|
|
return 0;
|
|
}
|
|
ccl_buf[ccl_bufidx++] = pattern[i++];
|
|
}
|
|
else if (ccl_bufidx >= MAX_CHAR_CLASS_LEN)
|
|
{
|
|
//fputs("exceeded internal buffer!\n", stderr);
|
|
return 0;
|
|
}
|
|
ccl_buf[ccl_bufidx++] = pattern[i];
|
|
}
|
|
if (ccl_bufidx >= MAX_CHAR_CLASS_LEN)
|
|
{
|
|
/* Catches cases such as [00000000000000000000000000000000000000][ */
|
|
//fputs("exceeded internal buffer!\n", stderr);
|
|
return 0;
|
|
}
|
|
/* Null-terminate string end */
|
|
ccl_buf[ccl_bufidx++] = 0;
|
|
re_compiled[j].ccl = &ccl_buf[buf_begin];
|
|
} break;
|
|
|
|
/* Other characters: */
|
|
default:
|
|
{
|
|
re_compiled[j].type = CHAR;
|
|
re_compiled[j].ch = c;
|
|
} break;
|
|
}
|
|
i += 1;
|
|
j += 1;
|
|
}
|
|
/* 'UNUSED' is a sentinel used to indicate end-of-pattern */
|
|
re_compiled[j].type = UNUSED;
|
|
|
|
re_p = (re_t)calloc(1, sizeof(re_compiled));
|
|
memcpy (re_p, re_compiled, sizeof(re_compiled));
|
|
return (re_t) re_p;
|
|
}
|
|
|
|
void re_print(regex_t* pattern)
|
|
{
|
|
const char* types[] = { "UNUSED", "DOT", "BEGIN", "END", "QUESTIONMARK", "STAR", "PLUS", "CHAR", "CHAR_CLASS", "INV_CHAR_CLASS", "DIGIT", "NOT_DIGIT", "ALPHA", "NOT_ALPHA", "WHITESPACE" , "NOT_WHITESPACE", /* "BRANCH" */ };
|
|
|
|
int i;
|
|
int j;
|
|
char c;
|
|
for (i = 0; i < MAX_REGEXP_OBJECTS; ++i)
|
|
{
|
|
if (pattern[i].type == UNUSED)
|
|
{
|
|
break;
|
|
}
|
|
|
|
printf("type: %s", types[pattern[i].type]);
|
|
if (pattern[i].type == CHAR_CLASS || pattern[i].type == INV_CHAR_CLASS)
|
|
{
|
|
printf(" [");
|
|
for (j = 0; j < MAX_CHAR_CLASS_LEN; ++j)
|
|
{
|
|
c = pattern[i].ccl[j];
|
|
if ((c == '\0') || (c == ']'))
|
|
{
|
|
break;
|
|
}
|
|
printf("%c", c);
|
|
}
|
|
printf("]");
|
|
}
|
|
else if (pattern[i].type == CHAR)
|
|
{
|
|
printf(" '%c'", pattern[i].ch);
|
|
}
|
|
printf("\n");
|
|
}
|
|
}
|
|
|
|
|
|
|
|
/* Private functions: */
|
|
static int matchdigit(char c)
|
|
{
|
|
return ((c >= '0') && (c <= '9'));
|
|
}
|
|
static int matchalpha(char c)
|
|
{
|
|
return ((c >= 'a') && (c <= 'z')) || ((c >= 'A') && (c <= 'Z'));
|
|
}
|
|
static int matchwhitespace(char c)
|
|
{
|
|
return ((c == ' ') || (c == '\t') || (c == '\n') || (c == '\r') || (c == '\f') || (c == '\v'));
|
|
}
|
|
static int matchalphanum(char c)
|
|
{
|
|
return ((c == '_') || matchalpha(c) || matchdigit(c));
|
|
}
|
|
static int matchrange(char c, const char* str)
|
|
{
|
|
return ((c != '-') && (str[0] != '\0') && (str[0] != '-') &&
|
|
(str[1] == '-') && (str[1] != '\0') &&
|
|
(str[2] != '\0') && ((c >= str[0]) && (c <= str[2])));
|
|
}
|
|
static int matchdot(char c)
|
|
{
|
|
return c != '\n' && c != '\r';
|
|
}
|
|
static int ismetachar(char c)
|
|
{
|
|
return ((c == 's') || (c == 'S') || (c == 'w') || (c == 'W') || (c == 'd') || (c == 'D'));
|
|
}
|
|
|
|
static int matchmetachar(char c, const char* str)
|
|
{
|
|
switch (str[0])
|
|
{
|
|
case 'd': return matchdigit(c);
|
|
case 'D': return !matchdigit(c);
|
|
case 'w': return matchalphanum(c);
|
|
case 'W': return !matchalphanum(c);
|
|
case 's': return matchwhitespace(c);
|
|
case 'S': return !matchwhitespace(c);
|
|
default: return (c == str[0]);
|
|
}
|
|
}
|
|
|
|
static int matchcharclass(char c, const char* str)
|
|
{
|
|
do
|
|
{
|
|
if (matchrange(c, str))
|
|
{
|
|
return 1;
|
|
}
|
|
else if (str[0] == '\\')
|
|
{
|
|
/* Escape-char: increment str-ptr and match on next char */
|
|
str += 1;
|
|
if (matchmetachar(c, str))
|
|
{
|
|
return 1;
|
|
}
|
|
else if ((c == str[0]) && !ismetachar(c))
|
|
{
|
|
return 1;
|
|
}
|
|
}
|
|
else if (c == str[0])
|
|
{
|
|
if (c == '-')
|
|
{
|
|
return ((str[-1] == '\0') || (str[1] == '\0'));
|
|
}
|
|
else
|
|
{
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
while (*str++ != '\0');
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int matchone(regex_t p, char c)
|
|
{
|
|
switch (p.type)
|
|
{
|
|
case DOT: return matchdot(c);
|
|
case CHAR_CLASS: return matchcharclass(c, (const char*)p.ccl);
|
|
case INV_CHAR_CLASS: return !matchcharclass(c, (const char*)p.ccl);
|
|
case DIGIT: return matchdigit(c);
|
|
case NOT_DIGIT: return !matchdigit(c);
|
|
case ALPHA: return matchalphanum(c);
|
|
case NOT_ALPHA: return !matchalphanum(c);
|
|
case WHITESPACE: return matchwhitespace(c);
|
|
case NOT_WHITESPACE: return !matchwhitespace(c);
|
|
default: return (p.ch == c);
|
|
}
|
|
}
|
|
|
|
static int matchstar(regex_t p, regex_t* pattern, const char* text, int* matchlength)
|
|
{
|
|
int prelen = *matchlength;
|
|
const char* prepoint = text;
|
|
while ((text[0] != '\0') && matchone(p, *text))
|
|
{
|
|
text++;
|
|
(*matchlength)++;
|
|
}
|
|
while (text >= prepoint)
|
|
{
|
|
if (matchpattern(pattern, text--, matchlength))
|
|
return 1;
|
|
(*matchlength)--;
|
|
}
|
|
|
|
*matchlength = prelen;
|
|
return 0;
|
|
}
|
|
|
|
static int matchplus(regex_t p, regex_t* pattern, const char* text, int* matchlength)
|
|
{
|
|
const char* prepoint = text;
|
|
while ((text[0] != '\0') && matchone(p, *text))
|
|
{
|
|
text++;
|
|
(*matchlength)++;
|
|
}
|
|
while (text > prepoint)
|
|
{
|
|
if (matchpattern(pattern, text--, matchlength))
|
|
return 1;
|
|
(*matchlength)--;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int matchquestion(regex_t p, regex_t* pattern, const char* text, int* matchlength)
|
|
{
|
|
if (p.type == UNUSED)
|
|
return 1;
|
|
if (matchpattern(pattern, text, matchlength))
|
|
return 1;
|
|
if (*text && matchone(p, *text++))
|
|
{
|
|
if (matchpattern(pattern, text, matchlength))
|
|
{
|
|
(*matchlength)++;
|
|
return 1;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
|
|
#if 0
|
|
|
|
/* Recursive matching */
|
|
static int matchpattern(regex_t* pattern, const char* text, int *matchlength)
|
|
{
|
|
int pre = *matchlength;
|
|
if ((pattern[0].type == UNUSED) || (pattern[1].type == QUESTIONMARK))
|
|
{
|
|
return matchquestion(pattern[1], &pattern[2], text, matchlength);
|
|
}
|
|
else if (pattern[1].type == STAR)
|
|
{
|
|
return matchstar(pattern[0], &pattern[2], text, matchlength);
|
|
}
|
|
else if (pattern[1].type == PLUS)
|
|
{
|
|
return matchplus(pattern[0], &pattern[2], text, matchlength);
|
|
}
|
|
else if ((pattern[0].type == END) && pattern[1].type == UNUSED)
|
|
{
|
|
return text[0] == '\0';
|
|
}
|
|
else if ((text[0] != '\0') && matchone(pattern[0], text[0]))
|
|
{
|
|
(*matchlength)++;
|
|
return matchpattern(&pattern[1], text+1);
|
|
}
|
|
else
|
|
{
|
|
*matchlength = pre;
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
#else
|
|
|
|
/* Iterative matching */
|
|
static int matchpattern(regex_t* pattern, const char* text, int* matchlength)
|
|
{
|
|
int pre = *matchlength;
|
|
do
|
|
{
|
|
if ((pattern[0].type == UNUSED) || (pattern[1].type == QUESTIONMARK))
|
|
{
|
|
return matchquestion(pattern[0], &pattern[2], text, matchlength);
|
|
}
|
|
else if (pattern[1].type == STAR)
|
|
{
|
|
return matchstar(pattern[0], &pattern[2], text, matchlength);
|
|
}
|
|
else if (pattern[1].type == PLUS)
|
|
{
|
|
return matchplus(pattern[0], &pattern[2], text, matchlength);
|
|
}
|
|
else if ((pattern[0].type == END) && pattern[1].type == UNUSED)
|
|
{
|
|
return (text[0] == '\0');
|
|
}
|
|
/* Branching is not working properly
|
|
else if (pattern[1].type == BRANCH)
|
|
{
|
|
return (matchpattern(pattern, text) || matchpattern(&pattern[2], text));
|
|
}
|
|
*/
|
|
(*matchlength)++;
|
|
}
|
|
while ((text[0] != '\0') && matchone(*pattern++, *text++));
|
|
|
|
*matchlength = pre;
|
|
return 0;
|
|
}
|
|
|
|
#endif
|
|
|