| /* |
| * Copyright (C) 2003 by Darren Reed. |
| * |
| * See the IPFILTER.LICENCE file for details on licencing. |
| */ |
| #include <ctype.h> |
| #include "ipf.h" |
| #ifdef IPFILTER_SCAN |
| # include "netinet/ip_scan.h" |
| #endif |
| #include <sys/ioctl.h> |
| #include <syslog.h> |
| #ifdef TEST_LEXER |
| # define NO_YACC |
| union { |
| int num; |
| char *str; |
| struct in_addr ipa; |
| i6addr_t ip6; |
| } yylval; |
| #endif |
| #include "lexer.h" |
| #include "y.tab.h" |
| |
| FILE *yyin; |
| |
| #define ishex(c) (ISDIGIT(c) || ((c) >= 'a' && (c) <= 'f') || \ |
| ((c) >= 'A' && (c) <= 'F')) |
| #define TOOLONG -3 |
| |
| extern int string_start; |
| extern int string_end; |
| extern char *string_val; |
| extern int pos; |
| extern int yydebug; |
| |
| char *yystr = NULL; |
| int yytext[YYBUFSIZ+1]; |
| int yylineNum = 1; |
| int yypos = 0; |
| int yylast = -1; |
| int yyexpectaddr = 0; |
| int yybreakondot = 0; |
| int yyvarnext = 0; |
| int yytokentype = 0; |
| wordtab_t *yywordtab = NULL; |
| int yysavedepth = 0; |
| wordtab_t *yysavewords[30]; |
| |
| |
| static wordtab_t *yyfindkey __P((char *)); |
| static int yygetc __P((void)); |
| static void yyunputc __P((int)); |
| static int yyswallow __P((int)); |
| static char *yytexttostr __P((int, int)); |
| static void yystrtotext __P((char *)); |
| |
| static int yygetc() |
| { |
| int c; |
| |
| if (yypos < yylast) { |
| c = yytext[yypos++]; |
| if (c == '\n') |
| yylineNum++; |
| return c; |
| } |
| |
| if (yypos == YYBUFSIZ) |
| return TOOLONG; |
| |
| if (pos >= string_start && pos <= string_end) { |
| c = string_val[pos - string_start]; |
| yypos++; |
| } else { |
| c = fgetc(yyin); |
| } |
| if (c == '\n') |
| yylineNum++; |
| yytext[yypos++] = c; |
| yylast = yypos; |
| yytext[yypos] = '\0'; |
| |
| return c; |
| } |
| |
| |
| static void yyunputc(c) |
| int c; |
| { |
| if (c == '\n') |
| yylineNum--; |
| yytext[--yypos] = c; |
| } |
| |
| |
| static int yyswallow(last) |
| int last; |
| { |
| int c; |
| |
| while (((c = yygetc()) > '\0') && (c != last)) |
| ; |
| |
| if (c != EOF) |
| yyunputc(c); |
| if (c == last) |
| return 0; |
| return -1; |
| } |
| |
| |
| static void yystrtotext(str) |
| char *str; |
| { |
| int len; |
| char *s; |
| |
| len = strlen(str); |
| if (len > YYBUFSIZ) |
| len = YYBUFSIZ; |
| |
| for (s = str; *s != '\0' && len > 0; s++, len--) |
| yytext[yylast++] = *s; |
| yytext[yylast] = '\0'; |
| } |
| |
| |
| static char *yytexttostr(offset, max) |
| int offset, max; |
| { |
| char *str; |
| int i; |
| |
| if ((yytext[offset] == '\'' || yytext[offset] == '"') && |
| (yytext[offset] == yytext[offset + max - 1])) { |
| offset++; |
| max--; |
| } |
| |
| if (max > yylast) |
| max = yylast; |
| str = malloc(max + 1); |
| if (str != NULL) { |
| for (i = offset; i < max; i++) |
| str[i - offset] = (char)(yytext[i] & 0xff); |
| str[i - offset] = '\0'; |
| } |
| return str; |
| } |
| |
| |
| int yylex() |
| { |
| int c, n, isbuilding, rval, lnext, nokey = 0; |
| char *name; |
| |
| isbuilding = 0; |
| lnext = 0; |
| rval = 0; |
| |
| if (yystr != NULL) { |
| free(yystr); |
| yystr = NULL; |
| } |
| |
| nextchar: |
| c = yygetc(); |
| |
| switch (c) |
| { |
| case '\n' : |
| lnext = 0; |
| nokey = 0; |
| case '\t' : |
| case '\r' : |
| case ' ' : |
| if (isbuilding == 1) { |
| yyunputc(c); |
| goto done; |
| } |
| if (yylast > yypos) { |
| bcopy(yytext + yypos, yytext, |
| sizeof(yytext[0]) * (yylast - yypos + 1)); |
| } |
| yylast -= yypos; |
| yypos = 0; |
| lnext = 0; |
| nokey = 0; |
| goto nextchar; |
| |
| case '\\' : |
| if (lnext == 0) { |
| lnext = 1; |
| if (yylast == yypos) { |
| yylast--; |
| yypos--; |
| } else |
| yypos--; |
| if (yypos == 0) |
| nokey = 1; |
| goto nextchar; |
| } |
| break; |
| } |
| |
| if (lnext == 1) { |
| lnext = 0; |
| if ((isbuilding == 0) && !ISALNUM(c)) { |
| return c; |
| } |
| goto nextchar; |
| } |
| |
| switch (c) |
| { |
| case '#' : |
| if (isbuilding == 1) { |
| yyunputc(c); |
| goto done; |
| } |
| yyswallow('\n'); |
| rval = YY_COMMENT; |
| goto nextchar; |
| |
| case '$' : |
| if (isbuilding == 1) { |
| yyunputc(c); |
| goto done; |
| } |
| n = yygetc(); |
| if (n == '{') { |
| if (yyswallow('}') == -1) { |
| rval = -2; |
| goto done; |
| } |
| (void) yygetc(); |
| } else { |
| if (!ISALPHA(n)) { |
| yyunputc(n); |
| break; |
| } |
| do { |
| n = yygetc(); |
| } while (ISALPHA(n) || ISDIGIT(n) || n == '_'); |
| yyunputc(n); |
| } |
| |
| name = yytexttostr(1, yypos); /* skip $ */ |
| |
| if (name != NULL) { |
| string_val = get_variable(name, NULL, yylineNum); |
| free(name); |
| if (string_val != NULL) { |
| name = yytexttostr(yypos, yylast); |
| if (name != NULL) { |
| yypos = 0; |
| yylast = 0; |
| yystrtotext(string_val); |
| yystrtotext(name); |
| free(string_val); |
| free(name); |
| goto nextchar; |
| } |
| free(string_val); |
| } |
| } |
| break; |
| |
| case '\'': |
| case '"' : |
| if (isbuilding == 1) { |
| goto done; |
| } |
| do { |
| n = yygetc(); |
| if (n == EOF || n == TOOLONG) { |
| rval = -2; |
| goto done; |
| } |
| if (n == '\n') { |
| yyunputc(' '); |
| yypos++; |
| } |
| } while (n != c); |
| yyunputc(n); |
| break; |
| |
| case EOF : |
| yylineNum = 1; |
| yypos = 0; |
| yylast = -1; |
| yyexpectaddr = 0; |
| yybreakondot = 0; |
| yyvarnext = 0; |
| yytokentype = 0; |
| return 0; |
| } |
| |
| if (strchr("=,/;{}()@", c) != NULL) { |
| if (isbuilding == 1) { |
| yyunputc(c); |
| goto done; |
| } |
| rval = c; |
| goto done; |
| } else if (c == '.') { |
| if (isbuilding == 0) { |
| rval = c; |
| goto done; |
| } |
| if (yybreakondot != 0) { |
| yyunputc(c); |
| goto done; |
| } |
| } |
| |
| switch (c) |
| { |
| case '-' : |
| if (yyexpectaddr) |
| break; |
| if (isbuilding == 1) |
| break; |
| n = yygetc(); |
| if (n == '>') { |
| isbuilding = 1; |
| goto done; |
| } |
| yyunputc(n); |
| rval = '-'; |
| goto done; |
| |
| case '!' : |
| if (isbuilding == 1) { |
| yyunputc(c); |
| goto done; |
| } |
| n = yygetc(); |
| if (n == '=') { |
| rval = YY_CMP_NE; |
| goto done; |
| } |
| yyunputc(n); |
| rval = '!'; |
| goto done; |
| |
| case '<' : |
| if (yyexpectaddr) |
| break; |
| if (isbuilding == 1) { |
| yyunputc(c); |
| goto done; |
| } |
| n = yygetc(); |
| if (n == '=') { |
| rval = YY_CMP_LE; |
| goto done; |
| } |
| if (n == '>') { |
| rval = YY_RANGE_OUT; |
| goto done; |
| } |
| yyunputc(n); |
| rval = YY_CMP_LT; |
| goto done; |
| |
| case '>' : |
| if (yyexpectaddr) |
| break; |
| if (isbuilding == 1) { |
| yyunputc(c); |
| goto done; |
| } |
| n = yygetc(); |
| if (n == '=') { |
| rval = YY_CMP_GE; |
| goto done; |
| } |
| if (n == '<') { |
| rval = YY_RANGE_IN; |
| goto done; |
| } |
| yyunputc(n); |
| rval = YY_CMP_GT; |
| goto done; |
| } |
| |
| /* |
| * Now for the reason this is here...IPv6 address parsing. |
| * The longest string we can expect is of this form: |
| * 0000:0000:0000:0000:0000:0000:000.000.000.000 |
| * not: |
| * 0000:0000:0000:0000:0000:0000:0000:0000 |
| */ |
| #ifdef USE_INET6 |
| if (yyexpectaddr == 1 && isbuilding == 0 && (ishex(c) || c == ':')) { |
| char ipv6buf[45 + 1], *s, oc; |
| int start; |
| |
| start = yypos; |
| s = ipv6buf; |
| oc = c; |
| |
| /* |
| * Perhaps we should implement stricter controls on what we |
| * swallow up here, but surely it would just be duplicating |
| * the code in inet_pton() anyway. |
| */ |
| do { |
| *s++ = c; |
| c = yygetc(); |
| } while ((ishex(c) || c == ':' || c == '.') && |
| (s - ipv6buf < 46)); |
| yyunputc(c); |
| *s = '\0'; |
| |
| if (inet_pton(AF_INET6, ipv6buf, &yylval.ip6) == 1) { |
| rval = YY_IPV6; |
| yyexpectaddr = 0; |
| goto done; |
| } |
| yypos = start; |
| c = oc; |
| } |
| #endif |
| |
| if (c == ':') { |
| if (isbuilding == 1) { |
| yyunputc(c); |
| goto done; |
| } |
| rval = ':'; |
| goto done; |
| } |
| |
| if (isbuilding == 0 && c == '0') { |
| n = yygetc(); |
| if (n == 'x') { |
| do { |
| n = yygetc(); |
| } while (ishex(n)); |
| yyunputc(n); |
| rval = YY_HEX; |
| goto done; |
| } |
| yyunputc(n); |
| } |
| |
| /* |
| * No negative numbers with leading - sign.. |
| */ |
| if (isbuilding == 0 && ISDIGIT(c)) { |
| do { |
| n = yygetc(); |
| } while (ISDIGIT(n)); |
| yyunputc(n); |
| rval = YY_NUMBER; |
| goto done; |
| } |
| |
| isbuilding = 1; |
| goto nextchar; |
| |
| done: |
| yystr = yytexttostr(0, yypos); |
| |
| if (isbuilding == 1) { |
| wordtab_t *w; |
| |
| w = NULL; |
| isbuilding = 0; |
| |
| if ((yyvarnext == 0) && (nokey == 0)) { |
| w = yyfindkey(yystr); |
| if (w == NULL && yywordtab != NULL) { |
| yyresetdict(); |
| w = yyfindkey(yystr); |
| } |
| } else |
| yyvarnext = 0; |
| if (w != NULL) |
| rval = w->w_value; |
| else |
| rval = YY_STR; |
| } |
| |
| if (rval == YY_STR && yysavedepth > 0) |
| yyresetdict(); |
| |
| yytokentype = rval; |
| |
| if (yydebug) |
| printf("lexed(%s) [%d,%d,%d] => %d\n", yystr, string_start, |
| string_end, pos, rval); |
| |
| switch (rval) |
| { |
| case YY_NUMBER : |
| sscanf(yystr, "%u", &yylval.num); |
| break; |
| |
| case YY_HEX : |
| sscanf(yystr, "0x%x", (u_int *)&yylval.num); |
| break; |
| |
| case YY_STR : |
| yylval.str = strdup(yystr); |
| break; |
| |
| default : |
| break; |
| } |
| |
| if (yylast > 0) { |
| bcopy(yytext + yypos, yytext, |
| sizeof(yytext[0]) * (yylast - yypos + 1)); |
| yylast -= yypos; |
| yypos = 0; |
| } |
| |
| return rval; |
| } |
| |
| |
| static wordtab_t *yyfindkey(key) |
| char *key; |
| { |
| wordtab_t *w; |
| |
| if (yywordtab == NULL) |
| return NULL; |
| |
| for (w = yywordtab; w->w_word != 0; w++) |
| if (strcasecmp(key, w->w_word) == 0) |
| return w; |
| return NULL; |
| } |
| |
| |
| char *yykeytostr(num) |
| int num; |
| { |
| wordtab_t *w; |
| |
| if (yywordtab == NULL) |
| return "<unknown>"; |
| |
| for (w = yywordtab; w->w_word; w++) |
| if (w->w_value == num) |
| return w->w_word; |
| return "<unknown>"; |
| } |
| |
| |
| wordtab_t *yysettab(words) |
| wordtab_t *words; |
| { |
| wordtab_t *save; |
| |
| save = yywordtab; |
| yywordtab = words; |
| return save; |
| } |
| |
| |
| void yyerror(msg) |
| char *msg; |
| { |
| char *txt, letter[2]; |
| int freetxt = 0; |
| |
| if (yytokentype < 256) { |
| letter[0] = yytokentype; |
| letter[1] = '\0'; |
| txt = letter; |
| } else if (yytokentype == YY_STR || yytokentype == YY_HEX || |
| yytokentype == YY_NUMBER) { |
| if (yystr == NULL) { |
| txt = yytexttostr(yypos, YYBUFSIZ); |
| freetxt = 1; |
| } else |
| txt = yystr; |
| } else { |
| txt = yykeytostr(yytokentype); |
| } |
| fprintf(stderr, "%s error at \"%s\", line %d\n", msg, txt, yylineNum); |
| if (freetxt == 1) |
| free(txt); |
| exit(1); |
| } |
| |
| |
| void yysetdict(newdict) |
| wordtab_t *newdict; |
| { |
| if (yysavedepth == sizeof(yysavewords)/sizeof(yysavewords[0])) { |
| fprintf(stderr, "%d: at maximum dictionary depth\n", |
| yylineNum); |
| return; |
| } |
| |
| yysavewords[yysavedepth++] = yysettab(newdict); |
| if (yydebug) |
| printf("yysavedepth++ => %d\n", yysavedepth); |
| } |
| |
| void yyresetdict() |
| { |
| if (yysavedepth > 0) { |
| yysettab(yysavewords[--yysavedepth]); |
| if (yydebug) |
| printf("yysavedepth-- => %d\n", yysavedepth); |
| } |
| } |
| |
| |
| |
| #ifdef TEST_LEXER |
| int main(argc, argv) |
| int argc; |
| char *argv[]; |
| { |
| int n; |
| |
| yyin = stdin; |
| |
| while ((n = yylex()) != 0) |
| printf("%d.n = %d [%s] %d %d\n", |
| yylineNum, n, yystr, yypos, yylast); |
| } |
| #endif |