| /* |
| * Patterns management functions. |
| * |
| * Copyright 2009-2010 EXCELIANCE, Emeric Brun <ebrun@exceliance.fr> |
| * |
| * 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. |
| * |
| */ |
| |
| #include <string.h> |
| #include <arpa/inet.h> |
| |
| #include <proto/arg.h> |
| #include <proto/pattern.h> |
| #include <proto/buffers.h> |
| #include <common/standard.h> |
| |
| /* static sample used in pattern_process() when <p> is NULL */ |
| static struct sample temp_smp; |
| |
| /* trash chunk used for pattern conversions */ |
| static struct chunk trash_chunk; |
| |
| /* trash buffers used or pattern conversions */ |
| static char pattern_trash_buf1[BUFSIZE]; |
| static char pattern_trash_buf2[BUFSIZE]; |
| |
| /* pattern_trash_buf point on used buffer*/ |
| static char *pattern_trash_buf = pattern_trash_buf1; |
| |
| /* list head of all known pattern fetch keywords */ |
| static struct pattern_fetch_kw_list pattern_fetches = { |
| .list = LIST_HEAD_INIT(pattern_fetches.list) |
| }; |
| |
| /* list head of all known pattern format conversion keywords */ |
| static struct pattern_conv_kw_list pattern_convs = { |
| .list = LIST_HEAD_INIT(pattern_convs.list) |
| }; |
| |
| /* |
| * Registers the pattern fetch keyword list <kwl> as a list of valid keywords for next |
| * parsing sessions. |
| */ |
| void pattern_register_fetches(struct pattern_fetch_kw_list *pfkl) |
| { |
| LIST_ADDQ(&pattern_fetches.list, &pfkl->list); |
| } |
| |
| /* |
| * Registers the pattern format coverstion keyword list <pckl> as a list of valid keywords for next |
| * parsing sessions. |
| */ |
| void pattern_register_convs(struct pattern_conv_kw_list *pckl) |
| { |
| LIST_ADDQ(&pattern_convs.list, &pckl->list); |
| } |
| |
| /* |
| * Returns the pointer on pattern fetch keyword structure identified by |
| * string of <len> in buffer <kw>. |
| * |
| */ |
| struct pattern_fetch *find_pattern_fetch(const char *kw, int len) |
| { |
| int index; |
| struct pattern_fetch_kw_list *kwl; |
| |
| list_for_each_entry(kwl, &pattern_fetches.list, list) { |
| for (index = 0; kwl->kw[index].kw != NULL; index++) { |
| if (strncmp(kwl->kw[index].kw, kw, len) == 0 && |
| kwl->kw[index].kw[len] == '\0') |
| return &kwl->kw[index]; |
| } |
| } |
| return NULL; |
| } |
| |
| /* |
| * Returns the pointer on pattern format conversion keyword structure identified by |
| * string of <len> in buffer <kw>. |
| * |
| */ |
| struct pattern_conv *find_pattern_conv(const char *kw, int len) |
| { |
| int index; |
| struct pattern_conv_kw_list *kwl; |
| |
| list_for_each_entry(kwl, &pattern_convs.list, list) { |
| for (index = 0; kwl->kw[index].kw != NULL; index++) { |
| if (strncmp(kwl->kw[index].kw, kw, len) == 0 && |
| kwl->kw[index].kw[len] == '\0') |
| return &kwl->kw[index]; |
| } |
| } |
| return NULL; |
| } |
| |
| |
| /* |
| * Returns a static trash struct chunk to use in pattern casts or format conversions |
| * Swiths the 2 available trash buffers to protect data during convert |
| */ |
| static struct chunk *get_trash_chunk(void) |
| { |
| if (pattern_trash_buf == pattern_trash_buf1) |
| pattern_trash_buf = pattern_trash_buf2; |
| else |
| pattern_trash_buf = pattern_trash_buf1; |
| |
| chunk_init(&trash_chunk, pattern_trash_buf, BUFSIZE); |
| |
| return &trash_chunk; |
| } |
| |
| /******************************************************************/ |
| /* Pattern casts functions */ |
| /* Note: these functions do *NOT* set the output type on the */ |
| /* sample, the caller is responsible for doing this on return. */ |
| /******************************************************************/ |
| |
| static int c_ip2int(struct sample *smp) |
| { |
| smp->data.uint = ntohl(smp->data.ipv4.s_addr); |
| return 1; |
| } |
| |
| static int c_ip2str(struct sample *smp) |
| { |
| struct chunk *trash = get_trash_chunk(); |
| |
| if (!inet_ntop(AF_INET, (void *)&smp->data.ipv4, trash->str, trash->size)) |
| return 0; |
| |
| trash->len = strlen(trash->str); |
| smp->data.str = *trash; |
| |
| return 1; |
| } |
| |
| static int c_ip2ipv6(struct sample *smp) |
| { |
| v4tov6(&smp->data.ipv6, &smp->data.ipv4); |
| return 1; |
| } |
| |
| static int c_ipv62str(struct sample *smp) |
| { |
| struct chunk *trash = get_trash_chunk(); |
| |
| if (!inet_ntop(AF_INET6, (void *)&smp->data.ipv6, trash->str, trash->size)) |
| return 0; |
| |
| trash->len = strlen(trash->str); |
| smp->data.str = *trash; |
| return 1; |
| } |
| |
| /* |
| static int c_ipv62ip(struct sample *smp) |
| { |
| return v6tov4(&smp->data.ipv4, &smp->data.ipv6); |
| } |
| */ |
| |
| static int c_int2ip(struct sample *smp) |
| { |
| smp->data.ipv4.s_addr = htonl(smp->data.uint); |
| return 1; |
| } |
| |
| static int c_str2ip(struct sample *smp) |
| { |
| if (!buf2ip(smp->data.str.str, smp->data.str.len, &smp->data.ipv4)) |
| return 0; |
| return 1; |
| } |
| |
| static int c_str2ipv6(struct sample *smp) |
| { |
| return inet_pton(AF_INET6, smp->data.str.str, &smp->data.ipv6); |
| } |
| |
| static int c_int2str(struct sample *smp) |
| { |
| struct chunk *trash = get_trash_chunk(); |
| char *pos; |
| |
| pos = ultoa_r(smp->data.uint, trash->str, trash->size); |
| |
| if (!pos) |
| return 0; |
| |
| trash->size = trash->size - (pos - trash->str); |
| trash->str = pos; |
| trash->len = strlen(pos); |
| smp->data.str = *trash; |
| return 1; |
| } |
| |
| static int c_datadup(struct sample *smp) |
| { |
| struct chunk *trash = get_trash_chunk(); |
| |
| trash->len = smp->data.str.len < trash->size ? smp->data.str.len : trash->size; |
| memcpy(trash->str, smp->data.str.str, trash->len); |
| smp->data.str = *trash; |
| return 1; |
| } |
| |
| |
| static int c_none(struct sample *smp) |
| { |
| return 1; |
| } |
| |
| static int c_str2int(struct sample *smp) |
| { |
| int i; |
| uint32_t ret = 0; |
| |
| for (i = 0; i < smp->data.str.len; i++) { |
| uint32_t val = smp->data.str.str[i] - '0'; |
| |
| if (val > 9) |
| break; |
| |
| ret = ret * 10 + val; |
| } |
| |
| smp->data.uint = ret; |
| return 1; |
| } |
| |
| /*****************************************************************/ |
| /* Pattern casts matrix: */ |
| /* pattern_casts[from type][to type] */ |
| /* NULL pointer used for impossible pattern casts */ |
| /*****************************************************************/ |
| |
| typedef int (*pattern_cast_fct)(struct sample *smp); |
| static pattern_cast_fct pattern_casts[SMP_TYPES][SMP_TYPES] = { |
| /* to: BOOL UINT SINT IPV4 IPV6 STR BIN CSTR CBIN */ |
| /* from: BOOL */ { c_none, c_none, c_none, NULL, NULL, NULL, NULL, NULL, NULL }, |
| /* UINT */ { c_none, c_none, c_none, c_int2ip, NULL, c_int2str, NULL, c_int2str, NULL }, |
| /* SINT */ { c_none, c_none, c_none, c_int2ip, NULL, c_int2str, NULL, c_int2str, NULL }, |
| /* IPV4 */ { NULL, c_ip2int, c_ip2int, c_none, c_ip2ipv6, c_ip2str, NULL, c_ip2str, NULL }, |
| /* IPV6 */ { NULL, NULL, NULL, NULL, c_none, c_ipv62str, NULL, c_ipv62str, NULL }, |
| /* STR */ { c_str2int, c_str2int, c_str2int, c_str2ip, c_str2ipv6, c_none, c_none, c_none, c_none }, |
| /* BIN */ { NULL, NULL, NULL, NULL, NULL, NULL, c_none, NULL, c_none }, |
| /* CSTR */ { c_str2int, c_str2int, c_str2int, c_str2ip, c_str2ipv6, c_datadup, c_datadup, c_none, c_none }, |
| /* CBIN */ { NULL, NULL, NULL, NULL, NULL, NULL, c_datadup, NULL, c_none }, |
| }; |
| |
| /* |
| * Parse a pattern expression configuration: |
| * fetch keyword followed by format conversion keywords. |
| * Returns a pointer on allocated pattern expression structure. |
| */ |
| struct pattern_expr *pattern_parse_expr(char **str, int *idx, char *err, int err_size) |
| { |
| const char *endw; |
| const char *end; |
| struct pattern_expr *expr; |
| struct pattern_fetch *fetch; |
| struct pattern_conv *conv; |
| unsigned long prev_type; |
| char *p; |
| |
| snprintf(err, err_size, "memory error."); |
| if (!str[*idx]) { |
| |
| snprintf(err, err_size, "missing fetch method."); |
| goto out_error; |
| } |
| |
| end = str[*idx] + strlen(str[*idx]); |
| endw = strchr(str[*idx], '('); |
| |
| if (!endw) |
| endw = end; |
| else if ((end-1)[0] != ')') { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "syntax error: missing ')' after keyword '%s'.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| |
| fetch = find_pattern_fetch(str[*idx], endw - str[*idx]); |
| if (!fetch) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "unknown fetch method '%s'.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| if (fetch->out_type >= SMP_TYPES) { |
| |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "returns type of fetch method '%s' is unknown.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| |
| prev_type = fetch->out_type; |
| expr = calloc(1, sizeof(struct pattern_expr)); |
| if (!expr) |
| goto out_error; |
| |
| LIST_INIT(&(expr->conv_exprs)); |
| expr->fetch = fetch; |
| |
| if (end != endw) { |
| char *err_msg = NULL; |
| int err_arg; |
| |
| if (!fetch->arg_mask) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "fetch method '%s' does not support any args.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| |
| if (make_arg_list(endw + 1, end - endw - 2, fetch->arg_mask, &expr->arg_p, &err_msg, NULL, &err_arg) < 0) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "invalid arg %d in fetch method '%s' : %s.", err_arg+1, p, err_msg); |
| free(p); |
| } |
| free(err_msg); |
| goto out_error; |
| } |
| |
| if (fetch->val_args && !fetch->val_args(expr->arg_p, &err_msg)) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "invalid args in fetch method '%s' : %s.", p, err_msg); |
| free(p); |
| } |
| free(err_msg); |
| goto out_error; |
| } |
| } |
| else if (fetch->arg_mask) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "missing args for fetch method '%s'.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| |
| for (*idx += 1; *(str[*idx]); (*idx)++) { |
| struct pattern_conv_expr *conv_expr; |
| |
| end = str[*idx] + strlen(str[*idx]); |
| endw = strchr(str[*idx], '('); |
| |
| if (!endw) |
| endw = end; |
| else if ((end-1)[0] != ')') { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "syntax error, missing ')' after keyword '%s'.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| |
| conv = find_pattern_conv(str[*idx], endw - str[*idx]); |
| if (!conv) |
| break; |
| |
| if (conv->in_type >= SMP_TYPES || |
| conv->out_type >= SMP_TYPES) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "returns type of conv method '%s' is unknown.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| |
| /* If impossible type conversion */ |
| if (!pattern_casts[prev_type][conv->in_type]) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "conv method '%s' cannot be applied.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| |
| prev_type = conv->out_type; |
| conv_expr = calloc(1, sizeof(struct pattern_conv_expr)); |
| if (!conv_expr) |
| goto out_error; |
| |
| LIST_ADDQ(&(expr->conv_exprs), &(conv_expr->list)); |
| conv_expr->conv = conv; |
| |
| if (end != endw) { |
| char *err_msg = NULL; |
| int err_arg; |
| |
| if (!conv->arg_mask) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| |
| if (p) { |
| snprintf(err, err_size, "conv method '%s' does not support any args.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| |
| if (make_arg_list(endw + 1, end - endw - 2, conv->arg_mask, &conv_expr->arg_p, &err_msg, NULL, &err_arg) < 0) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "invalid arg %d in conv method '%s' : %s.", err_arg+1, p, err_msg); |
| free(p); |
| } |
| free(err_msg); |
| goto out_error; |
| } |
| |
| if (conv->val_args && !conv->val_args(conv_expr->arg_p, &err_msg)) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "invalid args in conv method '%s' : %s.", p, err_msg); |
| free(p); |
| } |
| free(err_msg); |
| goto out_error; |
| } |
| } |
| else if (conv->arg_mask) { |
| p = my_strndup(str[*idx], endw - str[*idx]); |
| if (p) { |
| snprintf(err, err_size, "missing args for conv method '%s'.", p); |
| free(p); |
| } |
| goto out_error; |
| } |
| |
| } |
| |
| return expr; |
| |
| out_error: |
| /* TODO: prune_pattern_expr(expr); */ |
| return NULL; |
| } |
| |
| /* |
| * Process a fetch + format conversion of defined by the pattern expression <expr> |
| * on request or response considering the <opt> parameter. |
| * Returns a pointer on a typed pattern structure containing the result or NULL if |
| * pattern is not found or when format conversion failed. |
| * If <p> is not null, function returns results in structure pointed by <p>. |
| * If <p> is null, functions returns a pointer on a static pattern structure. |
| * |
| * Note: the fetch functions are required to properly set the return type. The |
| * conversion functions must do so too. However the cast functions do not need |
| * to since they're made to cast mutiple types according to what is required. |
| */ |
| struct sample *pattern_process(struct proxy *px, struct session *l4, void *l7, |
| unsigned int opt, |
| struct pattern_expr *expr, struct sample *p) |
| { |
| struct pattern_conv_expr *conv_expr; |
| |
| if (p == NULL) |
| p = &temp_smp; |
| |
| p->flags = 0; |
| if (!expr->fetch->process(px, l4, l7, opt, expr->arg_p, p)) |
| return NULL; |
| |
| list_for_each_entry(conv_expr, &expr->conv_exprs, list) { |
| /* we want to ensure that p->type can be casted into |
| * conv_expr->conv->in_type. We have 3 possibilities : |
| * - NULL => not castable. |
| * - c_none => nothing to do (let's optimize it) |
| * - other => apply cast and prepare to fail |
| */ |
| if (!pattern_casts[p->type][conv_expr->conv->in_type]) |
| return NULL; |
| |
| if (pattern_casts[p->type][conv_expr->conv->in_type] != c_none && |
| !pattern_casts[p->type][conv_expr->conv->in_type](p)) |
| return NULL; |
| |
| /* OK cast succeeded */ |
| |
| /* force the output type after a cast */ |
| p->type = conv_expr->conv->in_type; |
| if (!conv_expr->conv->process(conv_expr->arg_p, p)) |
| return NULL; |
| } |
| return p; |
| } |
| |
| /*****************************************************************/ |
| /* Pattern format convert functions */ |
| /* These functions set the data type on return. */ |
| /*****************************************************************/ |
| |
| static int pattern_conv_str2lower(const struct arg *arg_p, struct sample *smp) |
| { |
| int i; |
| |
| if (!smp->data.str.size) |
| return 0; |
| |
| for (i = 0; i < smp->data.str.len; i++) { |
| if ((smp->data.str.str[i] >= 'A') && (smp->data.str.str[i] <= 'Z')) |
| smp->data.str.str[i] += 'a' - 'A'; |
| } |
| smp->type = SMP_T_STR; |
| return 1; |
| } |
| |
| static int pattern_conv_str2upper(const struct arg *arg_p, struct sample *smp) |
| { |
| int i; |
| |
| if (!smp->data.str.size) |
| return 0; |
| |
| for (i = 0; i < smp->data.str.len; i++) { |
| if ((smp->data.str.str[i] >= 'a') && (smp->data.str.str[i] <= 'z')) |
| smp->data.str.str[i] += 'A' - 'a'; |
| } |
| smp->type = SMP_T_STR; |
| return 1; |
| } |
| |
| /* takes the netmask in arg_p */ |
| static int pattern_conv_ipmask(const struct arg *arg_p, struct sample *smp) |
| { |
| smp->data.ipv4.s_addr &= arg_p->data.ipv4.s_addr; |
| smp->type = SMP_T_IPV4; |
| return 1; |
| } |
| |
| /* Note: must not be declared <const> as its list will be overwritten */ |
| static struct pattern_conv_kw_list pattern_conv_kws = {{ },{ |
| { "upper", pattern_conv_str2upper, 0, NULL, SMP_T_STR, SMP_T_STR }, |
| { "lower", pattern_conv_str2lower, 0, NULL, SMP_T_STR, SMP_T_STR }, |
| { "ipmask", pattern_conv_ipmask, ARG1(1,MSK4), NULL, SMP_T_IPV4, SMP_T_IPV4 }, |
| { NULL, NULL, 0, 0, 0 }, |
| }}; |
| |
| __attribute__((constructor)) |
| static void __pattern_init(void) |
| { |
| /* register pattern format convert keywords */ |
| pattern_register_convs(&pattern_conv_kws); |
| } |