examples/ipsec-secgw/parser.c

/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright(c) 2016 Intel Corporation
 */
#include <rte_common.h>
#include <rte_crypto.h>
#include <rte_string_fns.h>

#include <cmdline_parse_string.h>
#include <cmdline_parse_num.h>
#include <cmdline_parse_ipaddr.h>
#include <cmdline_socket.h>
#include <cmdline.h>

#include "ipsec.h"
#include "parser.h"

#define PARSE_DELIMITER     " \f\n\r\t\v"
static int
parse_tokenize_string(char *string, char *tokens[], uint32_t *n_tokens)
{
    uint32_t i;

    if ((string == NULL) ||
        (tokens == NULL) ||
        (*n_tokens < 1))
        return -EINVAL;

    for (i = 0; i < *n_tokens; i++) {
        tokens[i] = strtok_r(string, PARSE_DELIMITER, &string);
        if (tokens[i] == NULL)
            break;
    }

    if ((i == *n_tokens) &&
        (NULL != strtok_r(string, PARSE_DELIMITER, &string)))
        return -E2BIG;

    *n_tokens = i;
    return 0;
}

#define INADDRSZ 4
#define IN6ADDRSZ 16

/* int
 * inet_pton4(src, dst)
 *      like inet_aton() but without all the hexadecimal and shorthand.
 * return:
 *      1 if `src' is a valid dotted quad, else 0.
 * notice:
 *      does not touch `dst' unless it's returning 1.
 * author:
 *      Paul Vixie, 1996.
 */
static int
inet_pton4(const char *src, unsigned char *dst)
{
    static const char digits[] = "0123456789";
    int saw_digit, octets, ch;
    unsigned char tmp[INADDRSZ], *tp;

    saw_digit = 0;
    octets = 0;
    *(tp = tmp) = 0;
    while ((ch = *src++) != '\0') {
        const char *pch;

        pch = strchr(digits, ch);
        if (pch != NULL) {
            unsigned int new = *tp * 10 + (pch - digits);

            if (new > 255)
                return 0;
            if (!saw_digit) {
                if (++octets > 4)
                    return 0;
                saw_digit = 1;
            }
            *tp = (unsigned char)new;
        } else if (ch == '.' && saw_digit) {
            if (octets == 4)
                return 0;
            *++tp = 0;
            saw_digit = 0;
        } else
            return 0;
    }
    if (octets < 4)
        return 0;

    memcpy(dst, tmp, INADDRSZ);
    return 1;
}

/* int
 * inet_pton6(src, dst)
 *      convert presentation level address to network order binary form.
 * return:
 *      1 if `src' is a valid [RFC1884 2.2] address, else 0.
 * notice:
 *      (1) does not touch `dst' unless it's returning 1.
 *      (2) :: in a full address is silently ignored.
 * credit:
 *      inspired by Mark Andrews.
 * author:
 *      Paul Vixie, 1996.
 */
static int
inet_pton6(const char *src, unsigned char *dst)
{
    static const char xdigits_l[] = "0123456789abcdef",
        xdigits_u[] = "0123456789ABCDEF";
    unsigned char tmp[IN6ADDRSZ], *tp = 0, *endp = 0, *colonp = 0;
    const char *xdigits = 0, *curtok = 0;
    int ch = 0, saw_xdigit = 0, count_xdigit = 0;
    unsigned int val = 0;
    unsigned dbloct_count = 0;

    memset((tp = tmp), '\0', IN6ADDRSZ);
    endp = tp + IN6ADDRSZ;
    colonp = NULL;
    /* Leading :: requires some special handling. */
    if (*src == ':')
        if (*++src != ':')
            return 0;
    curtok = src;
    saw_xdigit = count_xdigit = 0;
    val = 0;

    while ((ch = *src++) != '\0') {
        const char *pch;

        pch = strchr((xdigits = xdigits_l), ch);
        if (pch == NULL)
            pch = strchr((xdigits = xdigits_u), ch);
        if (pch != NULL) {
            if (count_xdigit >= 4)
                return 0;
            val <<= 4;
            val |= (pch - xdigits);
            if (val > 0xffff)
                return 0;
            saw_xdigit = 1;
            count_xdigit++;
            continue;
        }
        if (ch == ':') {
            curtok = src;
            if (!saw_xdigit) {
                if (colonp)
                    return 0;
                colonp = tp;
                continue;
            } else if (*src == '\0') {
                return 0;
            }
            if (tp + sizeof(int16_t) > endp)
                return 0;
            *tp++ = (unsigned char) ((val >> 8) & 0xff);
            *tp++ = (unsigned char) (val & 0xff);
            saw_xdigit = 0;
            count_xdigit = 0;
            val = 0;
            dbloct_count++;
            continue;
        }
        if (ch == '.' && ((tp + INADDRSZ) <= endp) &&
            inet_pton4(curtok, tp) > 0) {
            tp += INADDRSZ;
            saw_xdigit = 0;
            dbloct_count += 2;
            break;  /* '\0' was seen by inet_pton4(). */
        }
        return 0;
    }
    if (saw_xdigit) {
        if (tp + sizeof(int16_t) > endp)
            return 0;
        *tp++ = (unsigned char) ((val >> 8) & 0xff);
        *tp++ = (unsigned char) (val & 0xff);
        dbloct_count++;
    }
    if (colonp != NULL) {
        /* if we already have 8 double octets, having a colon
         * means error */
        if (dbloct_count == 8)
            return 0;

        /*
         * Since some memmove()'s erroneously fail to handle
         * overlapping regions, we'll do the shift by hand.
         */
        const int n = tp - colonp;
        int i;

        for (i = 1; i <= n; i++) {
            endp[-i] = colonp[n - i];
            colonp[n - i] = 0;
        }
        tp = endp;
    }
    if (tp != endp)
        return 0;
    memcpy(dst, tmp, IN6ADDRSZ);
    return 1;
}

int
parse_ipv4_addr(const char *token, struct in_addr *ipv4, uint32_t *mask)
{
    char ip_str[INET_ADDRSTRLEN] = {0};
    char *pch;

    pch = strchr(token, '/');
    if (pch != NULL) {
        strlcpy(ip_str, token,
            RTE_MIN((unsigned int long)(pch - token + 1),
            sizeof(ip_str)));
        pch += 1;
        if (is_str_num(pch) != 0)
            return -EINVAL;
        if (mask)
            *mask = atoi(pch);
    } else {
        strlcpy(ip_str, token, sizeof(ip_str));
        if (mask)
            *mask = 0;
    }
    if (strlen(ip_str) >= INET_ADDRSTRLEN)
        return -EINVAL;

    if (inet_pton4(ip_str, (unsigned char *)ipv4) != 1)
        return -EINVAL;

    return 0;
}

int
parse_ipv6_addr(const char *token, struct in6_addr *ipv6, uint32_t *mask)
{
    char ip_str[256] = {0};
    char *pch;

    pch = strchr(token, '/');
    if (pch != NULL) {
        strlcpy(ip_str, token,
            RTE_MIN((unsigned int long)(pch - token + 1),
                    sizeof(ip_str)));
        pch += 1;
        if (is_str_num(pch) != 0)
            return -EINVAL;
        if (mask)
            *mask = atoi(pch);
    } else {
        strlcpy(ip_str, token, sizeof(ip_str));
        if (mask)
            *mask = 0;
    }

    if (strlen(ip_str) >= INET6_ADDRSTRLEN)
        return -EINVAL;

    if (inet_pton6(ip_str, (unsigned char *)ipv6) != 1)
        return -EINVAL;

    return 0;
}

int
parse_range(const char *token, uint16_t *low, uint16_t *high)
{
    char ch;
    char num_str[20];
    uint32_t pos;
    int range_low = -1;
    int range_high = -1;

    if (!low || !high)
        return -1;

    memset(num_str, 0, 20);
    pos = 0;

    while ((ch = *token++) != '\0') {
        if (isdigit(ch)) {
            if (pos >= 19)
                return -1;
            num_str[pos++] = ch;
        } else if (ch == ':') {
            if (range_low != -1)
                return -1;
            range_low = atoi(num_str);
            memset(num_str, 0, 20);
            pos = 0;
        }
    }

    if (strlen(num_str) == 0)
        return -1;

    range_high = atoi(num_str);

    *low = (uint16_t)range_low;
    *high = (uint16_t)range_high;

    return 0;
}

struct cfg_sp_add_cfg_item {
    cmdline_fixed_string_t sp_keyword;
    cmdline_multi_string_t multi_string;
};

static void
cfg_sp_add_cfg_item_parsed(void *parsed_result,
    __rte_unused struct cmdline *cl, void *data)
{
    struct cfg_sp_add_cfg_item *params = parsed_result;
    char *tokens[32];
    uint32_t n_tokens = RTE_DIM(tokens);
    struct parse_status *status = (struct parse_status *)data;

    APP_CHECK((parse_tokenize_string(params->multi_string, tokens,
        &n_tokens) == 0), status, "too many arguments");

    if (status->status < 0)
        return;

    if (strcmp(tokens[0], "ipv4") == 0) {
        parse_sp4_tokens(tokens, n_tokens, status);
        if (status->status < 0)
            return;
    } else if (strcmp(tokens[0], "ipv6") == 0) {
        parse_sp6_tokens(tokens, n_tokens, status);
        if (status->status < 0)
            return;
    } else {
        APP_CHECK(0, status, "unrecognizable input %s\n",
            tokens[0]);
        return;
    }
}

static cmdline_parse_token_string_t cfg_sp_add_sp_str =
    TOKEN_STRING_INITIALIZER(struct cfg_sp_add_cfg_item,
        sp_keyword, "sp");

static cmdline_parse_token_string_t cfg_sp_add_multi_str =
    TOKEN_STRING_INITIALIZER(struct cfg_sp_add_cfg_item, multi_string,
        TOKEN_STRING_MULTI);

cmdline_parse_inst_t cfg_sp_add_rule = {
    .f = cfg_sp_add_cfg_item_parsed,
    .data = NULL,
    .help_str = "",
    .tokens = {
        (void *) &cfg_sp_add_sp_str,
        (void *) &cfg_sp_add_multi_str,
        NULL,
    },
};

/* sa add parse */
struct cfg_sa_add_cfg_item {
    cmdline_fixed_string_t sa_keyword;
    cmdline_multi_string_t multi_string;
};

static void
cfg_sa_add_cfg_item_parsed(void *parsed_result,
    __rte_unused struct cmdline *cl, void *data)
{
    struct cfg_sa_add_cfg_item *params = parsed_result;
    char *tokens[32];
    uint32_t n_tokens = RTE_DIM(tokens);
    struct parse_status *status = (struct parse_status *)data;

    APP_CHECK(parse_tokenize_string(params->multi_string, tokens,
        &n_tokens) == 0, status, "too many arguments\n");

    parse_sa_tokens(tokens, n_tokens, status);
}

static cmdline_parse_token_string_t cfg_sa_add_sa_str =
    TOKEN_STRING_INITIALIZER(struct cfg_sa_add_cfg_item,
        sa_keyword, "sa");

static cmdline_parse_token_string_t cfg_sa_add_multi_str =
    TOKEN_STRING_INITIALIZER(struct cfg_sa_add_cfg_item, multi_string,
        TOKEN_STRING_MULTI);

cmdline_parse_inst_t cfg_sa_add_rule = {
    .f = cfg_sa_add_cfg_item_parsed,
    .data = NULL,
    .help_str = "",
    .tokens = {
        (void *) &cfg_sa_add_sa_str,
        (void *) &cfg_sa_add_multi_str,
        NULL,
    },
};

/* rt add parse */
struct cfg_rt_add_cfg_item {
    cmdline_fixed_string_t rt_keyword;
    cmdline_multi_string_t multi_string;
};

static void
cfg_rt_add_cfg_item_parsed(void *parsed_result,
    __rte_unused struct cmdline *cl, void *data)
{
    struct cfg_rt_add_cfg_item *params = parsed_result;
    char *tokens[32];
    uint32_t n_tokens = RTE_DIM(tokens);
    struct parse_status *status = (struct parse_status *)data;

    APP_CHECK(parse_tokenize_string(
        params->multi_string, tokens, &n_tokens) == 0,
        status, "too many arguments\n");
    if (status->status < 0)
        return;

    parse_rt_tokens(tokens, n_tokens, status);
}

static cmdline_parse_token_string_t cfg_rt_add_rt_str =
    TOKEN_STRING_INITIALIZER(struct cfg_rt_add_cfg_item,
        rt_keyword, "rt");

static cmdline_parse_token_string_t cfg_rt_add_multi_str =
    TOKEN_STRING_INITIALIZER(struct cfg_rt_add_cfg_item, multi_string,
        TOKEN_STRING_MULTI);

cmdline_parse_inst_t cfg_rt_add_rule = {
    .f = cfg_rt_add_cfg_item_parsed,
    .data = NULL,
    .help_str = "",
    .tokens = {
        (void *) &cfg_rt_add_rt_str,
        (void *) &cfg_rt_add_multi_str,
        NULL,
    },
};

cmdline_parse_ctx_t ipsec_ctx[] = {
    (cmdline_parse_inst_t *)&cfg_sp_add_rule,
    (cmdline_parse_inst_t *)&cfg_sa_add_rule,
    (cmdline_parse_inst_t *)&cfg_rt_add_rule,
    NULL,
};

int
parse_cfg_file(const char *cfg_filename)
{
    struct cmdline *cl = cmdline_stdin_new(ipsec_ctx, "");
    FILE *f = fopen(cfg_filename, "r");
    char str[1024] = {0}, *get_s = NULL;
    uint32_t line_num = 0;
    struct parse_status status = {0};

    if (f == NULL) {
        rte_panic("Error: invalid file descriptor %s\n", cfg_filename);
        goto error_exit;
    }

    if (cl == NULL) {
        rte_panic("Error: cannot create cmdline instance\n");
        goto error_exit;
    }

    cfg_sp_add_rule.data = &status;
    cfg_sa_add_rule.data = &status;
    cfg_rt_add_rule.data = &status;

    do {
        char oneline[1024];
        char *pos;
        get_s = fgets(oneline, 1024, f);

        if (!get_s)
            break;

        line_num++;

        if (strlen(oneline) > 1022) {
            rte_panic("%s:%u: error: "
                "the line contains more characters the parser can handle\n",
                cfg_filename, line_num);
            goto error_exit;
        }

        /* process comment char '#' */
        if (oneline[0] == '#')
            continue;

        pos = strchr(oneline, '#');
        if (pos != NULL)
            *pos = '\0';

        /* process line concatenator '\' */
        pos = strchr(oneline, 92);
        if (pos != NULL) {
            if (pos != oneline+strlen(oneline) - 2) {
                rte_panic("%s:%u: error: "
                    "no character should exist after '\\'\n",
                    cfg_filename, line_num);
                goto error_exit;
            }

            *pos = '\0';

            if (strlen(oneline) + strlen(str) > 1022) {
                rte_panic("%s:%u: error: "
                    "the concatenated line contains more characters the parser can handle\n",
                    cfg_filename, line_num);
                goto error_exit;
            }

            strcpy(str + strlen(str), oneline);
            continue;
        }

        /* copy the line to str and process */
        if (strlen(oneline) + strlen(str) > 1022) {
            rte_panic("%s:%u: error: "
                "the line contains more characters the parser can handle\n",
                cfg_filename, line_num);
            goto error_exit;
        }
        strcpy(str + strlen(str), oneline);

        str[strlen(str)] = '\n';
        if (cmdline_parse(cl, str) < 0) {
            rte_panic("%s:%u: error: parsing \"%s\" failed\n",
                cfg_filename, line_num, str);
            goto error_exit;
        }

        if (status.status < 0) {
            rte_panic("%s:%u: error: %s", cfg_filename,
                line_num, status.parse_msg);
            goto error_exit;
        }

        memset(str, 0, 1024);
    } while (1);

    cmdline_stdin_exit(cl);
    fclose(f);

    return 0;

error_exit:
    if (cl)
        cmdline_stdin_exit(cl);
    if (f)
        fclose(f);

    return -1;
}