wpa_supplicant: Initial Revision 0.8.X

Based on:
commit 0725cc7b7efc434910e89865c42eda7ce61bbf08
Author: Jouni Malinen <j@w1.fi>
Date:   Thu Apr 21 20:41:01 2011 +0300

    Enable CONFIG_DRIVER_NL80211=y in the default configuration

    nl80211 should be preferred over WEXT with any recent Linux
    kernel version.

Change-Id: I26aec5afbbd4f4a1f5fd900912545b6f5050de64
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>
diff --git a/src/p2p/p2p_utils.c b/src/p2p/p2p_utils.c
new file mode 100644
index 0000000..da4b6ed
--- /dev/null
+++ b/src/p2p/p2p_utils.c
@@ -0,0 +1,271 @@
+/*
+ * P2P - generic helper functions
+ * Copyright (c) 2009, Atheros Communications
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "p2p_i.h"
+
+
+/**
+ * p2p_random - Generate random string for SSID and passphrase
+ * @buf: Buffer for returning the result
+ * @len: Number of octets to write to the buffer
+ * Returns: 0 on success, -1 on failure
+ *
+ * This function generates a random string using the following character set:
+ * 'A'-'Z', 'a'-'z', '0'-'9'.
+ */
+int p2p_random(char *buf, size_t len)
+{
+	u8 val;
+	size_t i;
+	u8 letters = 'Z' - 'A' + 1;
+	u8 numbers = 10;
+
+	if (os_get_random((unsigned char *) buf, len))
+		return -1;
+	/* Character set: 'A'-'Z', 'a'-'z', '0'-'9' */
+	for (i = 0; i < len; i++) {
+		val = buf[i];
+		val %= 2 * letters + numbers;
+		if (val < letters)
+			buf[i] = 'A' + val;
+		else if (val < 2 * letters)
+			buf[i] = 'a' + (val - letters);
+		else
+			buf[i] = '0' + (val - 2 * letters);
+	}
+
+	return 0;
+}
+
+
+static int p2p_channel_to_freq_j4(int reg_class, int channel)
+{
+	/* Table J-4 in P802.11REVmb/D4.0 - Global operating classes */
+	/* TODO: more regulatory classes */
+	switch (reg_class) {
+	case 81:
+		/* channels 1..13 */
+		if (channel < 1 || channel > 13)
+			return -1;
+		return 2407 + 5 * channel;
+	case 82:
+		/* channel 14 */
+		if (channel != 14)
+			return -1;
+		return 2414 + 5 * channel;
+	case 83: /* channels 1..9; 40 MHz */
+	case 84: /* channels 5..13; 40 MHz */
+		if (channel < 1 || channel > 13)
+			return -1;
+		return 2407 + 5 * channel;
+	case 115: /* channels 36,40,44,48; indoor only */
+	case 118: /* channels 52,56,60,64; dfs */
+		if (channel < 36 || channel > 64)
+			return -1;
+		return 5000 + 5 * channel;
+	case 124: /* channels 149,153,157,161 */
+	case 125: /* channels 149,153,157,161,165,169 */
+		if (channel < 149 || channel > 161)
+			return -1;
+		return 5000 + 5 * channel;
+	case 116: /* channels 36,44; 40 MHz; indoor only */
+	case 117: /* channels 40,48; 40 MHz; indoor only */
+	case 119: /* channels 52,60; 40 MHz; dfs */
+	case 120: /* channels 56,64; 40 MHz; dfs */
+		if (channel < 36 || channel > 64)
+			return -1;
+		return 5000 + 5 * channel;
+	case 126: /* channels 149,157; 40 MHz */
+	case 127: /* channels 153,161; 40 MHz */
+		if (channel < 149 || channel > 161)
+			return -1;
+		return 5000 + 5 * channel;
+	}
+	return -1;
+}
+
+
+/**
+ * p2p_channel_to_freq - Convert channel info to frequency
+ * @country: Country code
+ * @reg_class: Regulatory class
+ * @channel: Channel number
+ * Returns: Frequency in MHz or -1 if the specified channel is unknown
+ */
+int p2p_channel_to_freq(const char *country, int reg_class, int channel)
+{
+	if (country[2] == 0x04)
+		return p2p_channel_to_freq_j4(reg_class, channel);
+
+	/* These are mainly for backwards compatibility; to be removed */
+	switch (reg_class) {
+	case 1: /* US/1, EU/1, JP/1 = 5 GHz, channels 36,40,44,48 */
+		if (channel < 36 || channel > 48)
+			return -1;
+		return 5000 + 5 * channel;
+	case 3: /* US/3 = 5 GHz, channels 149,153,157,161 */
+	case 5: /* US/5 = 5 GHz, channels 149,153,157,161 */
+		if (channel < 149 || channel > 161)
+			return -1;
+		return 5000 + 5 * channel;
+	case 4: /* EU/4 = 2.407 GHz, channels 1..13 */
+	case 12: /* US/12 = 2.407 GHz, channels 1..11 */
+	case 30: /* JP/30 = 2.407 GHz, channels 1..13 */
+		if (channel < 1 || channel > 13)
+			return -1;
+		return 2407 + 5 * channel;
+	case 31: /* JP/31 = 2.414 GHz, channel 14 */
+		if (channel != 14)
+			return -1;
+		return 2414 + 5 * channel;
+	}
+
+	return -1;
+}
+
+
+/**
+ * p2p_freq_to_channel - Convert frequency into channel info
+ * @country: Country code
+ * @reg_class: Buffer for returning regulatory class
+ * @channel: Buffer for returning channel number
+ * Returns: 0 on success, -1 if the specified frequency is unknown
+ */
+int p2p_freq_to_channel(const char *country, unsigned int freq, u8 *reg_class,
+			u8 *channel)
+{
+	/* TODO: more operating classes */
+	if (freq >= 2412 && freq <= 2472) {
+		*reg_class = 81; /* 2.407 GHz, channels 1..13 */
+		*channel = (freq - 2407) / 5;
+		return 0;
+	}
+
+	if (freq == 2484) {
+		*reg_class = 82; /* channel 14 */
+		*channel = 14;
+		return 0;
+	}
+
+	if (freq >= 5180 && freq <= 5240) {
+		*reg_class = 115; /* 5 GHz, channels 36..48 */
+		*channel = (freq - 5000) / 5;
+		return 0;
+	}
+
+	if (freq >= 5745 && freq <= 5805) {
+		*reg_class = 124; /* 5 GHz, channels 149..161 */
+		*channel = (freq - 5000) / 5;
+		return 0;
+	}
+
+	return -1;
+}
+
+
+static void p2p_reg_class_intersect(const struct p2p_reg_class *a,
+				    const struct p2p_reg_class *b,
+				    struct p2p_reg_class *res)
+{
+	size_t i, j;
+
+	res->reg_class = a->reg_class;
+
+	for (i = 0; i < a->channels; i++) {
+		for (j = 0; j < b->channels; j++) {
+			if (a->channel[i] != b->channel[j])
+				continue;
+			res->channel[res->channels] = a->channel[i];
+			res->channels++;
+			if (res->channels == P2P_MAX_REG_CLASS_CHANNELS)
+				return;
+		}
+	}
+}
+
+
+/**
+ * p2p_channels_intersect - Intersection of supported channel lists
+ * @a: First set of supported channels
+ * @b: Second set of supported channels
+ * @res: Data structure for returning the intersection of support channels
+ *
+ * This function can be used to find a common set of supported channels. Both
+ * input channels sets are assumed to use the same country code. If different
+ * country codes are used, the regulatory class numbers may not be matched
+ * correctly and results are undefined.
+ */
+void p2p_channels_intersect(const struct p2p_channels *a,
+			    const struct p2p_channels *b,
+			    struct p2p_channels *res)
+{
+	size_t i, j;
+
+	os_memset(res, 0, sizeof(*res));
+
+	for (i = 0; i < a->reg_classes; i++) {
+		const struct p2p_reg_class *a_reg = &a->reg_class[i];
+		for (j = 0; j < b->reg_classes; j++) {
+			const struct p2p_reg_class *b_reg = &b->reg_class[j];
+			if (a_reg->reg_class != b_reg->reg_class)
+				continue;
+			p2p_reg_class_intersect(
+				a_reg, b_reg,
+				&res->reg_class[res->reg_classes]);
+			if (res->reg_class[res->reg_classes].channels) {
+				res->reg_classes++;
+				if (res->reg_classes == P2P_MAX_REG_CLASSES)
+					return;
+			}
+		}
+	}
+}
+
+
+/**
+ * p2p_channels_includes - Check whether a channel is included in the list
+ * @channels: List of supported channels
+ * @reg_class: Regulatory class of the channel to search
+ * @channel: Channel number of the channel to search
+ * Returns: 1 if channel was found or 0 if not
+ */
+int p2p_channels_includes(const struct p2p_channels *channels, u8 reg_class,
+			  u8 channel)
+{
+	size_t i, j;
+	for (i = 0; i < channels->reg_classes; i++) {
+		const struct p2p_reg_class *reg = &channels->reg_class[i];
+		if (reg->reg_class != reg_class)
+			continue;
+		for (j = 0; j < reg->channels; j++) {
+			if (reg->channel[j] == channel)
+				return 1;
+		}
+	}
+	return 0;
+}
+
+
+int p2p_supported_freq(struct p2p_data *p2p, unsigned int freq)
+{
+	u8 op_reg_class, op_channel;
+	if (p2p_freq_to_channel(p2p->cfg->country, freq,
+				&op_reg_class, &op_channel) < 0)
+		return 0;
+	return p2p_channels_includes(&p2p->cfg->channels, op_reg_class,
+				     op_channel);
+}