Adding upstream version 1:6.7.upstream/1%6.7

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1141 insertions, 0 deletions

diff --git a/netlink/parser.c b/netlink/parser.c
new file mode 100644
index 0000000..6f86361
--- /dev/null
+++ b/netlink/parser.c
@@ -0,0 +1,1141 @@
+/*
+ * parser.c - netlink command line parser
+ *
+ * Implementation of command line parser used by netlink code.
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+
+#include "../internal.h"
+#include "../common.h"
+#include "netlink.h"
+#include "parser.h"
+
+static void parser_err_unknown_param(struct nl_context *nlctx)
+{
+	fprintf(stderr, "ethtool (%s): unknown parameter '%s'\n", nlctx->cmd,
+		nlctx->param);
+}
+
+static void parser_err_dup_param(struct nl_context *nlctx)
+{
+	fprintf(stderr, "ethtool (%s): duplicate parameter '%s'\n", nlctx->cmd,
+		nlctx->param);
+}
+
+static void parser_err_min_argc(struct nl_context *nlctx, unsigned int min_argc)
+{
+	if (min_argc == 1)
+		fprintf(stderr, "ethtool (%s): no value for parameter '%s'\n",
+			nlctx->cmd, nlctx->param);
+	else
+		fprintf(stderr,
+			"ethtool (%s): parameter '%s' requires %u words\n",
+			nlctx->cmd, nlctx->param, min_argc);
+}
+
+static void parser_err_invalid_value(struct nl_context *nlctx, const char *val)
+{
+	fprintf(stderr, "ethtool (%s): invalid value '%s' for parameter '%s'\n",
+		nlctx->cmd, val, nlctx->param);
+}
+
+static void parser_err_invalid_flag(struct nl_context *nlctx, const char *flag)
+{
+	fprintf(stderr, "ethtool (%s): flag '%s' for parameter '%s' is not followed by 'on' or 'off'\n",
+		nlctx->cmd, flag, nlctx->param);
+}
+
+static bool __prefix_0x(const char *p)
+{
+	return p[0] == '0' && (p[1] == 'x' || p[1] == 'X');
+}
+
+static float parse_float(const char *arg, float *result, float min,
+			 float max)
+{
+	char *endptr;
+	float val;
+
+	if (!arg || !arg[0])
+		return -EINVAL;
+	val = strtof(arg, &endptr);
+	if (*endptr || val < min || val > max)
+		return -EINVAL;
+
+	*result = val;
+	return 0;
+}
+
+static int __parse_u32(const char *arg, uint32_t *result, uint32_t min,
+		       uint32_t max, int base)
+{
+	unsigned long long val;
+	char *endptr;
+
+	if (!arg || !arg[0])
+		return -EINVAL;
+	val = strtoul(arg, &endptr, base);
+	if (*endptr || val < min || val > max)
+		return -EINVAL;
+
+	*result = (uint32_t)val;
+	return 0;
+}
+
+static int parse_u32d(const char *arg, uint32_t *result)
+{
+	return __parse_u32(arg, result, 0, 0xffffffff, 10);
+}
+
+static int parse_x32(const char *arg, uint32_t *result)
+{
+	return __parse_u32(arg, result, 0, 0xffffffff, 16);
+}
+
+int parse_u32(const char *arg, uint32_t *result)
+{
+	if (!arg)
+		return -EINVAL;
+	if (__prefix_0x(arg))
+		return parse_x32(arg + 2, result);
+	else
+		return parse_u32d(arg, result);
+}
+
+static int parse_u8(const char *arg, uint8_t *result)
+{
+	uint32_t val;
+	int ret = parse_u32(arg, &val);
+
+	if (ret < 0)
+		return ret;
+	if (val > UINT8_MAX)
+		return -EINVAL;
+
+	*result = (uint8_t)val;
+	return 0;
+}
+
+static int lookup_u32(const char *arg, uint32_t *result,
+		      const struct lookup_entry_u32 *tbl)
+{
+	if (!arg)
+		return -EINVAL;
+	while (tbl->arg) {
+		if (!strcmp(tbl->arg, arg)) {
+			*result = tbl->val;
+			return 0;
+		}
+		tbl++;
+	}
+
+	return -EINVAL;
+}
+
+static int lookup_u8(const char *arg, uint8_t *result,
+		     const struct lookup_entry_u8 *tbl)
+{
+	if (!arg)
+		return -EINVAL;
+	while (tbl->arg) {
+		if (!strcmp(tbl->arg, arg)) {
+			*result = tbl->val;
+			return 0;
+		}
+		tbl++;
+	}
+
+	return -EINVAL;
+}
+
+/* Parser handler for a flag. Expects a name (with no additional argument),
+ * generates NLA_FLAG or sets a bool (if the name was present).
+ */
+int nl_parse_flag(struct nl_context *nlctx __maybe_unused, uint16_t type,
+		  const void *data __maybe_unused, struct nl_msg_buff *msgbuff,
+		  void *dest)
+{
+	if (dest)
+		*(bool *)dest = true;
+	return (type && ethnla_put_flag(msgbuff, type, true)) ? -EMSGSIZE : 0;
+}
+
+/* Parser handler for null terminated string. Expects a string argument,
+ * generates NLA_NUL_STRING or fills const char *
+ */
+int nl_parse_string(struct nl_context *nlctx, uint16_t type,
+		    const void *data __maybe_unused,
+		    struct nl_msg_buff *msgbuff, void *dest)
+{
+	const char *arg = *nlctx->argp;
+
+	nlctx->argp++;
+	nlctx->argc--;
+
+	if (dest)
+		*(const char **)dest = arg;
+	return (type && ethnla_put_strz(msgbuff, type, arg)) ? -EMSGSIZE : 0;
+}
+
+/* Parser handler for unsigned 32-bit integer. Expects a numeric argument
+ * (may use 0x prefix), generates NLA_U32 or fills an uint32_t.
+ */
+int nl_parse_direct_u32(struct nl_context *nlctx, uint16_t type,
+			const void *data __maybe_unused,
+			struct nl_msg_buff *msgbuff, void *dest)
+{
+	const char *arg = *nlctx->argp;
+	uint32_t val;
+	int ret;
+
+	nlctx->argp++;
+	nlctx->argc--;
+	ret = parse_u32(arg, &val);
+	if (ret < 0) {
+		parser_err_invalid_value(nlctx, arg);
+		return ret;
+	}
+
+	if (dest)
+		*(uint32_t *)dest = val;
+	return (type && ethnla_put_u32(msgbuff, type, val)) ? -EMSGSIZE : 0;
+}
+
+/* Parser handler for unsigned 32-bit integer. Expects a numeric argument
+ * (may use 0x prefix), generates NLA_U32 or fills an uint32_t.
+ */
+int nl_parse_direct_u8(struct nl_context *nlctx, uint16_t type,
+		       const void *data __maybe_unused,
+		       struct nl_msg_buff *msgbuff, void *dest)
+{
+	const char *arg = *nlctx->argp;
+	uint8_t val;
+	int ret;
+
+	nlctx->argp++;
+	nlctx->argc--;
+	ret = parse_u8(arg, &val);
+	if (ret < 0) {
+		parser_err_invalid_value(nlctx, arg);
+		return ret;
+	}
+
+	if (dest)
+		*(uint8_t *)dest = val;
+	return (type && ethnla_put_u8(msgbuff, type, val)) ? -EMSGSIZE : 0;
+}
+
+/* Parser handler for float meters and convert it to cm. Generates
+ * NLA_U32 or fills an uint32_t.
+ */
+int nl_parse_direct_m2cm(struct nl_context *nlctx, uint16_t type,
+			 const void *data __maybe_unused,
+			 struct nl_msg_buff *msgbuff, void *dest)
+{
+	const char *arg = *nlctx->argp;
+	float meters = 0.0;
+	uint32_t cm;
+	int ret;
+
+	nlctx->argp++;
+	nlctx->argc--;
+	ret = parse_float(arg, &meters, 0, 150);
+	if (ret < 0) {
+		parser_err_invalid_value(nlctx, arg);
+		return ret;
+	}
+
+	cm = (uint32_t)(meters * 100 + 0.5);
+	if (dest)
+		*(uint32_t *)dest = cm;
+	return (type && ethnla_put_u32(msgbuff, type, cm)) ? -EMSGSIZE : 0;
+}
+
+/* Parser handler for (tri-state) bool. Expects "name on|off", generates
+ * NLA_U8 which is 1 for "on" and 0 for "off".
+ */
+int nl_parse_u8bool(struct nl_context *nlctx, uint16_t type,
+		    const void *data __maybe_unused,
+		    struct nl_msg_buff *msgbuff, void *dest)
+{
+	const char *arg = *nlctx->argp;
+	int ret;
+
+	nlctx->argp++;
+	nlctx->argc--;
+	if (!strcmp(arg, "on")) {
+		if (dest)
+			*(uint8_t *)dest = 1;
+		ret = type ? ethnla_put_u8(msgbuff, type, 1) : 0;
+	} else if (!strcmp(arg, "off")) {
+		if (dest)
+			*(uint8_t *)dest = 0;
+		ret = type ? ethnla_put_u8(msgbuff, type, 0) : 0;
+	} else {
+		parser_err_invalid_value(nlctx, arg);
+		return -EINVAL;
+	}
+
+	return ret ? -EMSGSIZE : 0;
+}
+
+/* Parser handler for 32-bit lookup value. Expects a string argument, looks it
+ * up in a table, generates NLA_U32 or fills uint32_t variable. The @data
+ * parameter is a null terminated array of struct lookup_entry_u32.
+ */
+int nl_parse_lookup_u32(struct nl_context *nlctx, uint16_t type,
+			const void *data, struct nl_msg_buff *msgbuff,
+			void *dest)
+{
+	const char *arg = *nlctx->argp;
+	uint32_t val;
+	int ret;
+
+	nlctx->argp++;
+	nlctx->argc--;
+	ret = lookup_u32(arg, &val, data);
+	if (ret < 0) {
+		parser_err_invalid_value(nlctx, arg);
+		return ret;
+	}
+
+	if (dest)
+		*(uint32_t *)dest = val;
+	return (type && ethnla_put_u32(msgbuff, type, val)) ? -EMSGSIZE : 0;
+}
+
+/* Parser handler for 8-bit lookup value. Expects a string argument, looks it
+ * up in a table, generates NLA_U8 or fills uint8_t variable. The @data
+ * parameter is a null terminated array of struct lookup_entry_u8.
+ */
+int nl_parse_lookup_u8(struct nl_context *nlctx, uint16_t type,
+		       const void *data, struct nl_msg_buff *msgbuff,
+		       void *dest)
+{
+	const char *arg = *nlctx->argp;
+	uint8_t val;
+	int ret;
+
+	nlctx->argp++;
+	nlctx->argc--;
+	ret = lookup_u8(arg, &val, data);
+	if (ret < 0) {
+		parser_err_invalid_value(nlctx, arg);
+		return ret;
+	}
+
+	if (dest)
+		*(uint8_t *)dest = val;
+	return (type && ethnla_put_u8(msgbuff, type, val)) ? -EMSGSIZE : 0;
+}
+
+/* number of significant bits */
+static unsigned int __nsb(uint32_t x)
+{
+	unsigned int ret = 0;
+
+	if (x & 0xffff0000U) {
+		x >>= 16;
+		ret += 16;
+	}
+	if (x & 0xff00U) {
+		x >>= 8;
+		ret += 8;
+	}
+	if (x & 0xf0U) {
+		x >>= 4;
+		ret += 4;
+	}
+	if (x & 0xcU) {
+		x >>= 2;
+		ret += 2;
+	}
+	if (x & 0x2U) {
+		x >>= 1;
+		ret += 1;
+	}
+
+	return ret + x;
+}
+
+static bool __is_hex(char c)
+{
+	if (isdigit(c))
+		return true;
+	else
+		return (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F');
+}
+
+static unsigned int __hex_val(char c)
+{
+	if (c >= '0' && c <= '9')
+		return c - '0';
+	if (c >= 'a' && c <= 'f')
+		return c - 'a' + 0xa;
+	if (c >= 'A' && c <= 'F')
+		return c - 'A' + 0xa;
+	return 0;
+}
+
+static bool __bytestr_delim(const char *p, char delim)
+{
+	return !*p || (delim ? (*p == delim) : !__is_hex(*p));
+}
+
+/* Parser handler for generic byte string in MAC-like format. Expects string
+ * argument in the "[[:xdigit:]]{2}(:[[:xdigit:]]{2})*" format, generates
+ * NLA_BINARY or fills a struct byte_str_value (if @dest is not null and the
+ * handler succeeds, caller is responsible for freeing the value). The @data
+ * parameter points to struct byte_str_parser_data.
+ */
+int nl_parse_byte_str(struct nl_context *nlctx, uint16_t type, const void *data,
+		      struct nl_msg_buff *msgbuff, void *dest)
+{
+	const struct byte_str_parser_data *pdata = data;
+	struct byte_str_value *dest_value = dest;
+	const char *arg = *nlctx->argp;
+	uint8_t *val = NULL;
+	unsigned int len, i;
+	const char *p;
+	int ret;
+
+	nlctx->argp++;
+	nlctx->argc--;
+
+	len = 0;
+	p = arg;
+	if (!*p)
+		goto err;
+	while (true) {
+		len++;
+		if (!__bytestr_delim(p, pdata->delim))
+			p++;
+		if (!__bytestr_delim(p, pdata->delim))
+			p++;
+		if (!__bytestr_delim(p, pdata->delim))
+			goto err;
+		if (!*p)
+			break;
+		p++;
+		if (*p && __bytestr_delim(p, pdata->delim))
+			goto err;
+	}
+	if (len < pdata->min_len || (pdata->max_len && len > pdata->max_len))
+		goto err;
+	val = malloc(len);
+	if (!val)
+		return -ENOMEM;
+
+	p = arg;
+	for (i = 0; i < len; i++) {
+		uint8_t byte = 0;
+
+		if (!__is_hex(*p))
+			goto err;
+		while (__is_hex(*p))
+			byte = 16 * byte + __hex_val(*p++);
+		if (!__bytestr_delim(p, pdata->delim))
+			goto err;
+		val[i] = byte;
+		if (*p)
+			p++;
+	}
+	ret = type ? ethnla_put(msgbuff, type, len, val) : 0;
+	if (dest) {
+		dest_value->len = len;
+		dest_value->data = val;
+	} else {
+		free(val);
+	}
+	return ret;
+
+err:
+	free(val);
+	fprintf(stderr, "ethtool (%s): invalid value '%s' of parameter '%s'\n",
+		nlctx->cmd, arg, nlctx->param);
+	return -EINVAL;
+}
+
+/* Parser handler for parameters recognized for backward compatibility but
+ * supposed to fail without passing to kernel. Does not generate any netlink
+ * attributes of fill any variable. The @data parameter points to struct
+ * error_parser_params (error message, return value and number of extra
+ * arguments to skip).
+ */
+int nl_parse_error(struct nl_context *nlctx, uint16_t type __maybe_unused,
+		   const void *data, struct nl_msg_buff *msgbuff __maybe_unused,
+		   void *dest __maybe_unused)
+{
+	const struct error_parser_data *parser_data = data;
+	unsigned int skip = parser_data->extra_args;
+
+	fprintf(stderr, "ethtool (%s): ", nlctx->cmd);
+	fprintf(stderr, parser_data->err_msg, nlctx->param);
+	if (nlctx->argc < skip) {
+		fprintf(stderr, "ethtool (%s): too few arguments for parameter '%s' (expected %u)\n",
+			nlctx->cmd, nlctx->param, skip);
+	} else {
+		nlctx->argp += skip;
+		nlctx->argc -= skip;
+	}
+
+	return parser_data->ret_val;
+}
+
+/* bitset parser handlers */
+
+/* Return true if a bitset argument should be parsed as numeric, i.e.
+ * (a) it starts with '0x'
+ * (b) it consists only of hex digits and at most one slash which can be
+ *     optionally followed by "0x"; if no_mask is true, slash is not allowed
+ */
+static bool is_numeric_bitset(const char *arg, bool no_mask)
+{
+	const char *p = arg;
+	bool has_slash = false;
+
+	if (!arg)
+		return false;
+	if (__prefix_0x(arg))
+		return true;
+	while (*p) {
+		if (*p == '/') {
+			if (has_slash || no_mask)
+				return false;
+			has_slash = true;
+			p++;
+			if (__prefix_0x(p))
+				p += 2;
+			continue;
+		}
+		if (!__is_hex(*p))
+			return false;
+		p++;
+	}
+	return true;
+}
+
+#define __MAX_U32_DIGITS 10
+
+/* Parse hex string (without leading "0x") into a bitmap consisting of 32-bit
+ * words. Caller must make sure arg is at least len characters long and dst has
+ * place for at least (len + 7) / 8 32-bit words. If force_hex is false, allow
+ * also base 10 unsigned 32-bit value.
+ *
+ * Returns number of significant bits in the bitmap on success and negative
+ * value on error.
+ */
+static int __parse_num_string(const char *arg, unsigned int len, uint32_t *dst,
+			      bool force_hex)
+{
+	char buff[__MAX_U32_DIGITS + 1] = {};
+	unsigned int nbits = 0;
+	const char *p = arg;
+
+	if (!len)
+		return -EINVAL;
+	if (!force_hex && len <= __MAX_U32_DIGITS) {
+		strncpy(buff, arg, len);
+		if (!buff[__MAX_U32_DIGITS]) {
+			u32 val;
+			int ret;
+
+			ret = parse_u32d(buff, &val);
+			if (!ret) {
+				*dst = val;
+				return __nsb(val);
+			}
+		}
+	}
+
+	dst += (len - 1) / 8;
+	while (len > 0) {
+		unsigned int chunk = (len % 8) ?: 8;
+		unsigned long val;
+		char *endp;
+
+		memcpy(buff, p, chunk);
+		buff[chunk] = '\0';
+		val = strtoul(buff, &endp, 16);
+		if (*endp)
+			return -EINVAL;
+		*dst-- = (uint32_t)val;
+		if (nbits)
+			nbits += 4 * chunk;
+		else
+			nbits = __nsb(val);
+
+		p += chunk;
+		len -= chunk;
+	}
+	return nbits;
+}
+
+/* Parse bitset provided as a base 16 numeric value (@no_mask is true) or pair
+ * of base 16 numeric values  separated by '/' (@no_mask is false). The "0x"
+ * prefix is optional. Generates bitset nested attribute in compact form.
+ */
+static int parse_numeric_bitset(struct nl_context *nlctx, uint16_t type,
+				bool no_mask, bool force_hex,
+				struct nl_msg_buff *msgbuff)
+{
+	unsigned int nwords, len1, len2;
+	const char *arg = *nlctx->argp;
+	bool force_hex1 = force_hex;
+	bool force_hex2 = force_hex;
+	uint32_t *value = NULL;
+	uint32_t *mask = NULL;
+	struct nlattr *nest;
+	const char *maskptr;
+	int ret = 0;
+	int nbits;
+
+	if (__prefix_0x(arg)) {
+		force_hex1 = true;
+		arg += 2;
+	}
+
+	maskptr = strchr(arg, '/');
+	if (maskptr && no_mask) {
+		parser_err_invalid_value(nlctx, arg);
+		return -EINVAL;
+	}
+	len1 = maskptr ? (unsigned int)(maskptr - arg) : strlen(arg);
+	nwords = DIV_ROUND_UP(len1, 8);
+	nbits = 0;
+
+	if (maskptr) {
+		maskptr++;
+		if (__prefix_0x(maskptr)) {
+			maskptr += 2;
+			force_hex2 = true;
+		}
+		len2 = strlen(maskptr);
+		if (len2 > len1)
+			nwords = DIV_ROUND_UP(len2, 8);
+		mask = calloc(nwords, sizeof(uint32_t));
+		if (!mask)
+			return -ENOMEM;
+		ret = __parse_num_string(maskptr, strlen(maskptr), mask,
+					 force_hex2);
+		if (ret < 0) {
+			parser_err_invalid_value(nlctx, arg);
+			goto out_free;
+		}
+		nbits = ret;
+	}
+
+	value = calloc(nwords, sizeof(uint32_t));
+	if (!value) {
+		free(mask);
+		return -ENOMEM;
+	}
+	ret = __parse_num_string(arg, len1, value, force_hex1);
+	if (ret < 0) {
+		parser_err_invalid_value(nlctx, arg);
+		goto out_free;
+	}
+	nbits = (nbits < ret) ? ret : nbits;
+	nwords = (nbits + 31) / 32;
+
+	ret = 0;
+	if (!type)
+		goto out_free;
+	ret = -EMSGSIZE;
+	nest = ethnla_nest_start(msgbuff, type);
+	if (!nest)
+	       goto out_free;
+	if (ethnla_put_flag(msgbuff, ETHTOOL_A_BITSET_NOMASK, !mask) ||
+	    ethnla_put_u32(msgbuff, ETHTOOL_A_BITSET_SIZE, nbits) ||
+	    ethnla_put(msgbuff, ETHTOOL_A_BITSET_VALUE,
+		       nwords * sizeof(uint32_t), value) ||
+	    (mask &&
+	     ethnla_put(msgbuff, ETHTOOL_A_BITSET_MASK,
+			nwords * sizeof(uint32_t), mask)))
+		goto out_free;
+	ethnla_nest_end(msgbuff, nest);
+	ret = 0;
+
+out_free:
+	free(value);
+	free(mask);
+	nlctx->argp++;
+	nlctx->argc--;
+	return ret;
+}
+
+/* Parse bitset provided as series of "name on|off" pairs (@no_mask is false)
+ * or names (@no_mask is true). Generates bitset nested attribute in verbose
+ * form with names from command line.
+ */
+static int parse_name_bitset(struct nl_context *nlctx, uint16_t type,
+			     bool no_mask, struct nl_msg_buff *msgbuff)
+{
+	struct nlattr *bitset_attr;
+	struct nlattr *bits_attr;
+	struct nlattr *bit_attr;
+	int ret;
+
+	bitset_attr = ethnla_nest_start(msgbuff, type);
+	if (!bitset_attr)
+		return -EMSGSIZE;
+	ret = -EMSGSIZE;
+	if (no_mask && ethnla_put_flag(msgbuff, ETHTOOL_A_BITSET_NOMASK, true))
+		goto err;
+	bits_attr = ethnla_nest_start(msgbuff, ETHTOOL_A_BITSET_BITS);
+	if (!bits_attr)
+		goto err;
+
+	while (nlctx->argc > 0) {
+		bool bit_val = true;
+
+		if (!strcmp(*nlctx->argp, "--")) {
+			nlctx->argp++;
+			nlctx->argc--;
+			break;
+		}
+		ret = -EINVAL;
+		if (!no_mask) {
+			if (nlctx->argc < 2 ||
+			    (strcmp(nlctx->argp[1], "on") &&
+			     strcmp(nlctx->argp[1], "off"))) {
+				parser_err_invalid_flag(nlctx, *nlctx->argp);
+				goto err;
+			}
+			bit_val = !strcmp(nlctx->argp[1], "on");
+		}
+
+		ret = -EMSGSIZE;
+		bit_attr = ethnla_nest_start(msgbuff,
+					     ETHTOOL_A_BITSET_BITS_BIT);
+		if (!bit_attr)
+			goto err;
+		if (ethnla_put_strz(msgbuff, ETHTOOL_A_BITSET_BIT_NAME,
+				    nlctx->argp[0]))
+			goto err;
+		if (!no_mask &&
+		    ethnla_put_flag(msgbuff, ETHTOOL_A_BITSET_BIT_VALUE,
+				    bit_val))
+			goto err;
+		ethnla_nest_end(msgbuff, bit_attr);
+
+		nlctx->argp += (no_mask ? 1 : 2);
+		nlctx->argc -= (no_mask ? 1 : 2);
+	}
+
+	ethnla_nest_end(msgbuff, bits_attr);
+	ethnla_nest_end(msgbuff, bitset_attr);
+	return 0;
+err:
+	ethnla_nest_cancel(msgbuff, bitset_attr);
+	return ret;
+}
+
+static bool is_char_bitset(const char *arg,
+			   const struct char_bitset_parser_data *data)
+{
+	bool mask = (arg[0] == '+' || arg[0] == '-');
+	unsigned int i;
+	const char *p;
+
+	for (p = arg; *p; p++) {
+		if (*p == data->reset_char)
+			continue;
+		if (mask && (*p == '+' || *p == '-'))
+			continue;
+		for (i = 0; i < data->nbits; i++)
+			if (*p == data->bit_chars[i])
+				goto found;
+		return false;
+found:
+		;
+	}
+
+	return true;
+}
+
+/* Parse bitset provided as a string consisting of characters corresponding to
+ * bit indices. The "reset character" resets the no-mask bitset to empty. If
+ * the first character is '+' or '-', generated bitset has mask and '+' and
+ * '-' switch between enabling and disabling the following bits (i.e. their
+ * value being true/false). In such case, "reset character" is not allowed.
+ */
+static int parse_char_bitset(struct nl_context *nlctx, uint16_t type,
+			     const struct char_bitset_parser_data *data,
+			     struct nl_msg_buff *msgbuff)
+{
+	const char *arg = *nlctx->argp;
+	struct nlattr *bitset_attr;
+	struct nlattr *saved_pos;
+	struct nlattr *bits_attr;
+	struct nlattr *bit_attr;
+	unsigned int idx;
+	bool val = true;
+	const char *p;
+	bool no_mask;
+	int ret;
+
+	no_mask = data->no_mask || !(arg[0] == '+' || arg[0] == '-');
+	bitset_attr = ethnla_nest_start(msgbuff, type);
+	if (!bitset_attr)
+		return -EMSGSIZE;
+	ret = -EMSGSIZE;
+	if (no_mask && ethnla_put_flag(msgbuff, ETHTOOL_A_BITSET_NOMASK, true))
+		goto err;
+	bits_attr = ethnla_nest_start(msgbuff, ETHTOOL_A_BITSET_BITS);
+	if (!bits_attr)
+		goto err;
+	saved_pos = mnl_nlmsg_get_payload_tail(msgbuff->nlhdr);
+
+	for (p = arg; *p; p++) {
+		if (*p == '+' || *p == '-') {
+			if (no_mask) {
+				parser_err_invalid_value(nlctx, arg);
+				ret = -EINVAL;
+				goto err;
+			}
+			val = (*p == '+');
+			continue;
+		}
+		if (*p == data->reset_char) {
+			if (no_mask) {
+				mnl_attr_nest_cancel(msgbuff->nlhdr, saved_pos);
+				continue;
+			}
+			fprintf(stderr, "ethtool (%s): invalid char '%c' in '%s' for parameter '%s'\n",
+				nlctx->cmd, *p, arg, nlctx->param);
+			ret = -EINVAL;
+			goto err;
+		}
+
+		for (idx = 0; idx < data->nbits; idx++) {
+			if (data->bit_chars[idx] == *p)
+				break;
+		}
+		if (idx >= data->nbits) {
+			fprintf(stderr, "ethtool (%s): invalid char '%c' in '%s' for parameter '%s'\n",
+				nlctx->cmd, *p, arg, nlctx->param);
+			ret = -EINVAL;
+			goto err;
+		}
+		bit_attr = ethnla_nest_start(msgbuff,
+					     ETHTOOL_A_BITSET_BITS_BIT);
+		if (!bit_attr)
+			goto err;
+		if (ethnla_put_u32(msgbuff, ETHTOOL_A_BITSET_BIT_INDEX, idx))
+			goto err;
+		if (!no_mask &&
+		    ethnla_put_flag(msgbuff, ETHTOOL_A_BITSET_BIT_VALUE, val))
+			goto err;
+		ethnla_nest_end(msgbuff, bit_attr);
+	}
+
+	ethnla_nest_end(msgbuff, bits_attr);
+	ethnla_nest_end(msgbuff, bitset_attr);
+	nlctx->argp++;
+	nlctx->argc--;
+	return 0;
+err:
+	ethnla_nest_cancel(msgbuff, bitset_attr);
+	return ret;
+}
+
+/* Parser handler for bitset. Expects either a numeric value (base 16 or 10
+ * (unless force_hex is set)), optionally followed by '/' and another numeric
+ * value (mask, unless no_mask is set), or a series of "name on|off" pairs
+ * (no_mask not set) or names (no_mask set). In the latter case, names are
+ * passed on as they are and kernel performs their interpretation and
+ * validation. The @data parameter points to struct bitset_parser_data.
+ * Generates only a bitset nested attribute. Fails if @type is zero or @dest
+ * is not null.
+ */
+int nl_parse_bitset(struct nl_context *nlctx, uint16_t type, const void *data,
+		    struct nl_msg_buff *msgbuff, void *dest)
+{
+	const struct bitset_parser_data *parser_data = data;
+
+	if (!type || dest) {
+		fprintf(stderr, "ethtool (%s): internal error parsing '%s'\n",
+			nlctx->cmd, nlctx->param);
+		return -EFAULT;
+	}
+	if (is_numeric_bitset(*nlctx->argp, false))
+		return parse_numeric_bitset(nlctx, type, parser_data->no_mask,
+					    parser_data->force_hex, msgbuff);
+	else
+		return parse_name_bitset(nlctx, type, parser_data->no_mask,
+					 msgbuff);
+}
+
+/* Parser handler for bitset. Expects either a numeric value (base 10 or 16),
+ * optionally followed by '/' and another numeric value (mask, unless no_mask
+ * is set), or a string consisting of characters corresponding to bit indices.
+ * The @data parameter points to struct char_bitset_parser_data. Generates
+ * biset nested attribute. Fails if type is zero or if @dest is not null.
+ */
+int nl_parse_char_bitset(struct nl_context *nlctx, uint16_t type,
+			 const void *data, struct nl_msg_buff *msgbuff,
+			 void *dest)
+{
+	const struct char_bitset_parser_data *parser_data = data;
+
+	if (!type || dest) {
+		fprintf(stderr, "ethtool (%s): internal error parsing '%s'\n",
+			nlctx->cmd, nlctx->param);
+		return -EFAULT;
+	}
+	if (is_char_bitset(*nlctx->argp, data) ||
+	    !is_numeric_bitset(*nlctx->argp, false))
+		return parse_char_bitset(nlctx, type, parser_data, msgbuff);
+	else
+		return parse_numeric_bitset(nlctx, type, parser_data->no_mask,
+					    false, msgbuff);
+}
+
+/* parser implementation */
+
+static const struct param_parser *find_parser(const struct param_parser *params,
+					      const char *arg)
+{
+	const struct param_parser *parser;
+
+	for (parser = params; parser->arg; parser++)
+		if (!strcmp(arg, parser->arg))
+			return parser;
+	return NULL;
+}
+
+static bool __parser_bit(const uint64_t *map, unsigned int idx)
+{
+	return map[idx / 64] & (1 << (idx % 64));
+}
+
+static void __parser_set(uint64_t *map, unsigned int idx)
+{
+	map[idx / 64] |= (1 << (idx % 64));
+}
+
+static void __parser_set_group(const struct param_parser *params,
+			       uint64_t *map, unsigned int alt_group)
+{
+	const struct param_parser *parser;
+	unsigned int idx = 0;
+
+	for (parser = params; parser->arg; parser++, idx++)
+		if (parser->alt_group == alt_group)
+			__parser_set(map, idx);
+}
+
+struct tmp_buff {
+	struct nl_msg_buff	*msgbuff;
+	unsigned int		id;
+	unsigned int		orig_len;
+	struct tmp_buff		*next;
+};
+
+static struct tmp_buff *tmp_buff_find(struct tmp_buff *head, unsigned int id)
+{
+	struct tmp_buff *buff;
+
+	for (buff = head; buff; buff = buff->next)
+		if (buff->id == id)
+			break;
+
+	return buff;
+}
+
+static struct tmp_buff *tmp_buff_find_or_create(struct tmp_buff **phead,
+						unsigned int id)
+{
+	struct tmp_buff **pbuff;
+	struct tmp_buff *new_buff;
+
+	for (pbuff = phead; *pbuff; pbuff = &(*pbuff)->next)
+		if ((*pbuff)->id == id)
+			return *pbuff;
+
+	new_buff = malloc(sizeof(*new_buff));
+	if (!new_buff)
+		return NULL;
+	new_buff->id = id;
+	new_buff->msgbuff = malloc(sizeof(*new_buff->msgbuff));
+	if (!new_buff->msgbuff) {
+		free(new_buff);
+		return NULL;
+	}
+	msgbuff_init(new_buff->msgbuff);
+	new_buff->next = NULL;
+	*pbuff = new_buff;
+
+	return new_buff;
+}
+
+static void tmp_buff_destroy(struct tmp_buff *head)
+{
+	struct tmp_buff *buff = head;
+	struct tmp_buff *next;
+
+	while (buff) {
+		next = buff->next;
+		if (buff->msgbuff) {
+			msgbuff_done(buff->msgbuff);
+			free(buff->msgbuff);
+		}
+		free(buff);
+		buff = next;
+	}
+}
+
+/* Main entry point of parser implementation.
+ * @nlctx: netlink context
+ * @params:      array of struct param_parser describing expected arguments
+ *               and their handlers; the array must be terminated by null
+ *               element {}
+ * @dest:        optional destination to copy parsed data to (at
+ *               param_parser::offset)
+ * @group_style: defines if identifiers in .group represent separate messages,
+ *               nested attributes or are not allowed
+ * @msgbuffs:    (only used for @group_style = PARSER_GROUP_MSG) array to store
+ *               pointers to composed messages; caller must make sure this
+ *               array is sufficient, i.e. that it has at least as many entries
+ *               as the number of different .group values in params array;
+ *               entries are filled from the start, remaining entries are not
+ *               modified; caller should zero initialize the array before
+ *               calling nl_parser()
+ */
+int nl_parser(struct nl_context *nlctx, const struct param_parser *params,
+	      void *dest, enum parser_group_style group_style,
+	      struct nl_msg_buff **msgbuffs)
+{
+	struct nl_socket *nlsk = nlctx->ethnl_socket;
+	const struct param_parser *parser;
+	struct tmp_buff *buffs = NULL;
+	unsigned int n_msgbuffs = 0;
+	struct tmp_buff *buff;
+	unsigned int n_params;
+	uint64_t *params_seen;
+	int ret;
+
+	n_params = 0;
+	for (parser = params; parser->arg; parser++) {
+		struct nl_msg_buff *msgbuff;
+		struct nlattr *nest;
+
+		n_params++;
+		if (group_style == PARSER_GROUP_NONE || !parser->group)
+			continue;
+		ret = -ENOMEM;
+		buff = tmp_buff_find_or_create(&buffs, parser->group);
+		if (!buff)
+			goto out_free_buffs;
+		msgbuff = buff->msgbuff;
+		ret = msg_init(nlctx, msgbuff, parser->group,
+			       NLM_F_REQUEST | NLM_F_ACK);
+		if (ret < 0)
+			goto out_free_buffs;
+
+		switch (group_style) {
+		case PARSER_GROUP_NEST:
+			ret = -EMSGSIZE;
+			nest = ethnla_nest_start(buff->msgbuff, parser->group);
+			if (!nest)
+				goto out_free_buffs;
+			break;
+		case PARSER_GROUP_MSG:
+			if (ethnla_fill_header(msgbuff,
+					       ETHTOOL_A_LINKINFO_HEADER,
+					       nlctx->devname, 0))
+				goto out_free_buffs;
+			break;
+		default:
+			break;
+		}
+
+		buff->orig_len = msgbuff_len(msgbuff);
+	}
+	ret = -ENOMEM;
+	params_seen = calloc(DIV_ROUND_UP(n_params, 64), sizeof(uint64_t));
+	if (!params_seen)
+		goto out_free_buffs;
+
+	while (nlctx->argc > 0) {
+		struct nl_msg_buff *msgbuff;
+		void *param_dest;
+
+		nlctx->param = *nlctx->argp;
+		ret = -EINVAL;
+		parser = find_parser(params, nlctx->param);
+		if (!parser) {
+			parser_err_unknown_param(nlctx);
+			goto out_free;
+		}
+
+		/* check duplicates and minimum number of arguments */
+		if (__parser_bit(params_seen, parser - params)) {
+			parser_err_dup_param(nlctx);
+			goto out_free;
+		}
+		nlctx->argc--;
+		nlctx->argp++;
+		if (nlctx->argc < parser->min_argc) {
+			parser_err_min_argc(nlctx, parser->min_argc);
+			goto out_free;
+		}
+		if (parser->alt_group)
+			__parser_set_group(params, params_seen,
+					   parser->alt_group);
+		else
+			__parser_set(params_seen, parser - params);
+
+		buff = NULL;
+		if (parser->group)
+			buff = tmp_buff_find(buffs, parser->group);
+		msgbuff = buff ? buff->msgbuff : &nlsk->msgbuff;
+
+		param_dest = dest ? ((char *)dest + parser->dest_offset) : NULL;
+		ret = parser->handler(nlctx, parser->type, parser->handler_data,
+				      msgbuff, param_dest);
+		if (ret < 0)
+			goto out_free;
+	}
+
+	if (group_style == PARSER_GROUP_MSG) {
+		ret = -EOPNOTSUPP;
+		for (buff = buffs; buff; buff = buff->next)
+			if (msgbuff_len(buff->msgbuff) > buff->orig_len &&
+			    netlink_cmd_check(nlctx->ctx, buff->id, false))
+				goto out_free;
+	}
+	for (buff = buffs; buff; buff = buff->next) {
+		struct nl_msg_buff *msgbuff = buff->msgbuff;
+
+		if (group_style == PARSER_GROUP_NONE ||
+		    msgbuff_len(msgbuff) == buff->orig_len)
+			continue;
+		switch (group_style) {
+		case PARSER_GROUP_NEST:
+			ethnla_nest_end(msgbuff, msgbuff->payload);
+			ret = msgbuff_append(&nlsk->msgbuff, msgbuff);
+			if (ret < 0)
+				goto out_free;
+			break;
+		case PARSER_GROUP_MSG:
+			msgbuffs[n_msgbuffs++] = msgbuff;
+			buff->msgbuff = NULL;
+			break;
+		default:
+			break;
+		}
+	}
+
+	ret = 0;
+out_free:
+	free(params_seen);
+out_free_buffs:
+	tmp_buff_destroy(buffs);
+	return ret;
+}