X-Git-Url: https://roy.marples.name/git

diff --git a/src/libdhcpcd/wpa.c b/src/libdhcpcd/wpa.c
index 4861c5c..358b373 100644
--- a/src/libdhcpcd/wpa.c
+++ b/src/libdhcpcd/wpa.c
@@ -29,6 +29,7 @@
 #include <sys/un.h>
 
 #include <assert.h>
+#include <ctype.h>
 #include <errno.h>
 #include <limits.h>
 #include <poll.h>
@@ -191,13 +192,92 @@ dhcpcd_strtoi(int *val, const char *s)
 		errno = ERANGE;
 }
 
+static int
+dhcpcd_wpa_hex2num(char c)
+{
+
+	if (c >= '0' && c <= '9')
+		return c - '0';
+	if (c >= 'a' && c <= 'f')
+		return c - 'a' + 10;
+	if (c >= 'A' && c <= 'F')
+		return c - 'A' + 10;
+	return -1;
+}
+
+static int
+dhcpcd_wpa_hex2byte(const char *src)
+{
+	int h, l;
+
+	if ((h = dhcpcd_wpa_hex2num(*src++)) == -1 ||
+	    (l = dhcpcd_wpa_hex2num(*src)) == -1)
+		return -1;
+	return (h << 4) | l;
+}
+
+static ssize_t
+dhcpcd_wpa_decode_ssid(char *dst, size_t dlen, const char *src)
+{
+	const char *start;
+	char c, esc;
+	int xb;
+
+	start = dst;
+	for (;;) {
+		if (*src == '\0')
+			break;
+		if (--dlen == 0) {
+			errno = ENOSPC;
+			return -1;
+		}
+		c = *src++;
+		switch (c) {
+		case '\\':
+			if (*src == '\0') {
+				errno = EINVAL;
+				return -1;
+			}
+			esc = *src++;
+			switch (esc) {
+			case '\\':
+			case '"': *dst++ = esc; break;
+			case 'n': *dst++ = '\n'; break;
+			case 'r': *dst++ = '\r'; break;
+			case 't': *dst++ = '\t'; break;
+			case 'e': *dst++ = '\033'; break;
+			case 'x':
+				if (src[0] == '\0' || src[1] == '\0') {
+					errno = EINVAL;
+					return -1;
+				}
+				if ((xb = dhcpcd_wpa_hex2byte(src)) == -1)
+					return -1;
+				*dst++ = (char)xb;
+				src += 2;
+				break;
+			default: errno = EINVAL; return -1;
+			}
+		default: *dst++ = c; break;
+		}
+	}
+	if (dlen == 0) {
+		errno = ENOSPC;
+		return -1;
+	}
+	*dst = '\0';
+	return dst - start;
+}
+
 static DHCPCD_WI_SCAN *
 dhcpcd_wpa_scans_read(DHCPCD_WPA *wpa)
 {
 	size_t i;
-	ssize_t bytes;
+	ssize_t bytes, dl;
 	DHCPCD_WI_SCAN *wis, *w, *l;
 	char *s, *p, buf[32];
+	char wssid[sizeof(w->ssid)];
+	const char *proto;
 
 	if (!dhcpcd_realloc(wpa->con, 2048))
 		return NULL;
@@ -213,11 +293,8 @@ dhcpcd_wpa_scans_read(DHCPCD_WPA *wpa)
 		w = calloc(1, sizeof(*w));
 		if (w == NULL)
 			break;
-		if (wis == NULL)
-			wis = w;
-		else
-			l->next = w;
-		l = w;
+		dl = 0;
+		wssid[0] = '\0';
 		while ((s = strsep(&p, "\n"))) {
 			if (*s == '\0')
 				continue;
@@ -234,10 +311,50 @@ dhcpcd_wpa_scans_read(DHCPCD_WPA *wpa)
 			else if (strncmp(s, "level=", 6) == 0)
 				dhcpcd_strtoi(&w->level.value, s + 6);
 			else if (strncmp(s, "flags=", 6) == 0)
-				strlcpy(w->flags, s + 6, sizeof(w->flags));
-			else if (strncmp(s, "ssid=", 5) == 0)
-				strlcpy(w->ssid, s + 5, sizeof(w->ssid));
+				strlcpy(w->wpa_flags, s + 6,
+				    sizeof(w->wpa_flags));
+			else if (strncmp(s, "ssid=", 5) == 0) {
+				/* Decode it from \xNN to \NNN
+				 * so we're consistent */
+				dl = dhcpcd_wpa_decode_ssid(wssid,
+				    sizeof(wssid), s + 5);
+				if (dl == -1)
+					break;
+				dl = dhcpcd_encode_string_escape(w->ssid,
+				    sizeof(w->ssid), wssid, (size_t)dl);
+				if (dl == -1)
+					break;
+			}
+		}
+		if (dl == -1) {
+			free(w);
+			break;
+		}
+
+		if (wis == NULL)
+			wis = w;
+		else
+			l->next = w;
+		l = w;
+
+		if ((proto = strstr(w->wpa_flags, "[WPA-")) ||
+		    (proto = strstr(w->wpa_flags, "[WPA2-")) ||
+		    (proto = strstr(w->wpa_flags, "[RSN-")))
+		{
+			const char *endp, *psk;
+
+			w->flags = WSF_WPA | WSF_SECURE;
+			endp = strchr(proto, ']');
+			if ((psk = strstr(proto, "-PSK]")) ||
+			    (psk = strstr(proto, "-PSK-")) ||
+			    (psk = strstr(proto, "-PSK+")))
+			{
+				if (psk < endp)
+					w->flags |= WSF_PSK;
+			}
 		}
+		if (strstr(w->wpa_flags, "[WEP]"))
+			w->flags = WSF_WEP | WSF_PSK | WSF_SECURE;
 
 		w->strength.value = w->level.value;
 		if (w->strength.value > 110 && w->strength.value < 256)
@@ -254,16 +371,133 @@ dhcpcd_wpa_scans_read(DHCPCD_WPA *wpa)
 			/* Assume quality percentage */
 			w->strength.value = CLAMP(w->strength.value, 0, 100);
 		}
-
 	}
 	return wis;
 }
 
+int
+dhcpcd_wi_scan_compare(DHCPCD_WI_SCAN *a, DHCPCD_WI_SCAN *b)
+{
+	int cmp;
+
+	/* Fist sort non case sensitive, then case sensitive */
+	cmp = strcasecmp(a->ssid, b->ssid);
+	if (cmp == 0)
+		cmp = strcmp(a->ssid, b->ssid);
+
+	/* If still the same, return strongest first */
+	if (cmp == 0)
+		cmp = b->strength.value - a->strength.value;
+
+	return cmp;
+}
+
+/*
+ * This function is copyright 2001 Simon Tatham.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT.  IN NO EVENT SHALL SIMON TATHAM BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+ * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+static DHCPCD_WI_SCAN *
+dhcpcd_wi_scans_sort(DHCPCD_WI_SCAN *list)
+{
+	DHCPCD_WI_SCAN *p, *q, *e, *tail;
+	size_t insize, nmerges, psize, qsize, i;
+
+	/* Silly special case: if `list' was passed in as NULL, return
+	 * NULL immediately. */
+	if (!list)
+		return NULL;
+
+	insize = 1;
+
+	for (;;) {
+		p = list;
+		list = tail = NULL;
+		nmerges = 0;  /* count number of merges we do in this pass */
+
+		while (p) {
+			nmerges++;  /* there exists a merge to be done */
+			/* step `insize' places along from p */
+			q = p;
+			psize = 0;
+			for (i = 0; i < insize; i++) {
+				psize++;
+				q = q->next;
+				if (!q)
+					break;
+			}
+
+			/* if q hasn't fallen off end,
+			 * we have two lists to merge */
+			qsize = insize;
+
+			/* now we have two lists; merge them */
+			while (psize > 0 || (qsize > 0 && q)) {
+				/* decide whether next element of merge comes
+				 * from p or q */
+				if (psize == 0) {
+					/* p is empty; e must come from q. */
+					e = q; q = q->next; qsize--;
+				} else if (qsize == 0 || !q) {
+					/* q is empty; e must come from p. */
+					e = p; p = p->next; psize--;
+				} else if (dhcpcd_wi_scan_compare(p, q) <= 0) {
+					/* First element of p is lower
+					 * (or same); e must come from p. */
+					e = p; p = p->next; psize--;
+				} else {
+					/* First element of q is lower;
+					 * e must come from q. */
+					e = q; q = q->next; qsize--;
+				}
+
+				/* add the next element to the merged list */
+				if (tail)
+					tail->next = e;
+				else
+					list = e;
+				tail = e;
+			}
+
+			/* now p has stepped `insize' places along,
+			 * and q has too */
+			p = q;
+		}
+		tail->next = NULL;
+
+		/* If we have done only one merge, we're finished. */
+		if (nmerges <= 1)   /* allow for nmerges==0, the empty list */
+			return list;
+
+		/* Otherwise repeat, merging lists twice the size */
+		insize *= 2;
+	}
+}
+
 DHCPCD_WI_SCAN *
 dhcpcd_wi_scans(DHCPCD_IF *i)
 {
 	DHCPCD_WPA *wpa;
-	DHCPCD_WI_SCAN *wis, *w;
+	DHCPCD_WI_SCAN *wis, *w, *n, *p;
 	int nh;
 	DHCPCD_WI_HIST *h, *hl;
 
@@ -271,7 +505,30 @@ dhcpcd_wi_scans(DHCPCD_IF *i)
 	if (wpa == NULL)
 		return NULL;
 	wis = dhcpcd_wpa_scans_read(wpa);
-	for (w = wis; w; w = w->next) {
+
+	/* Sort the resultant list alphabetically and then by strength */
+	wis = dhcpcd_wi_scans_sort(wis);
+
+	p = NULL;
+	for (w = wis; w && (n = w->next, 1); w = n) {
+		/* Currently we don't support non SSID broadcasting APs */
+		if (*w->ssid == '\0') {
+			if (p == NULL)
+				wis = n;
+			else
+				p->next = n;
+			free(w);
+			continue;
+		}
+		/* Strip duplicated SSIDs, only show the strongest */
+		if (p && strcmp(p->ssid, w->ssid) == 0) {
+			p->next = n;
+			free(w);
+			continue;
+		}
+		/* Remember this as the previos next time */
+		p = w;
+
 		nh = 1;
 		hl = NULL;
 		w->quality.average = w->quality.value;
@@ -319,6 +576,13 @@ dhcpcd_wi_scans(DHCPCD_IF *i)
 }
 
 bool
+dhcpcd_wpa_reconfigure(DHCPCD_WPA *wpa)
+{
+
+	return dhcpcd_wpa_command(wpa, "RECONFIGURE");
+}
+
+bool
 dhcpcd_wpa_reassociate(DHCPCD_WPA *wpa)
 {
 
@@ -366,6 +630,13 @@ dhcpcd_wpa_network_enable(DHCPCD_WPA *wpa, int id)
 }
 
 bool
+dhcpcd_wpa_network_select(DHCPCD_WPA *wpa, int id)
+{
+
+	return dhcpcd_wpa_network(wpa, "SELECT_NETWORK", id);
+}
+
+bool
 dhcpcd_wpa_network_remove(DHCPCD_WPA *wpa, int id)
 {
 
@@ -409,8 +680,10 @@ dhcpcd_wpa_network_set(DHCPCD_WPA *wpa, int id,
 static int
 dhcpcd_wpa_network_find(DHCPCD_WPA *wpa, const char *fssid)
 {
-	ssize_t bytes;
+	ssize_t bytes, dl, tl;
+	size_t fl;
 	char *s, *t, *ssid, *bssid, *flags;
+	char dssid[IF_SSIDSIZE], tssid[IF_SSIDSIZE];
 	long l;
 
 	dhcpcd_realloc(wpa->con, 2048);
@@ -419,10 +692,12 @@ dhcpcd_wpa_network_find(DHCPCD_WPA *wpa, const char *fssid)
 	if (bytes == 0 || bytes == -1)
 		return -1;
 
+	fl = strlen(fssid);
+
 	s = strchr(wpa->con->buf, '\n');
 	if (s == NULL)
 		return -1;
-	while ((t = strsep(&s, "\b"))) {
+	while ((t = strsep(&s, "\b\n"))) {
 		if (*t == '\0')
 			continue;
 		ssid = strchr(t, '\t');
@@ -442,7 +717,18 @@ dhcpcd_wpa_network_find(DHCPCD_WPA *wpa, const char *fssid)
 			errno = ERANGE;
 			break;
 		}
-		if (strcmp(ssid, fssid) == 0)
+
+		/* Decode the wpa_supplicant SSID into raw chars and
+		 * then encode into our octal escaped string to
+		 * compare. */
+		dl = dhcpcd_wpa_decode_ssid(dssid, sizeof(dssid), ssid);
+		if (dl == -1)
+			return -1;
+		tl = dhcpcd_encode_string_escape(tssid,
+		    sizeof(tssid), dssid, (size_t)dl);
+		if (tl == -1)
+			return -1;
+		if ((size_t)tl == fl && memcmp(tssid, fssid, (size_t)tl) == 0)
 			return (int)l;
 	}
 	errno = ENOENT;
@@ -468,14 +754,50 @@ dhcpcd_wpa_network_new(DHCPCD_WPA *wpa)
 	return (int)l;
 }
 
+static const char hexchrs[] = "0123456789abcdef";
 int
 dhcpcd_wpa_network_find_new(DHCPCD_WPA *wpa, const char *ssid)
 {
 	int id;
+	char dssid[IF_SSIDSIZE], essid[IF_SSIDSIZE], *ep;
+	ssize_t dl, i;
+	char *dp;
 
 	id = dhcpcd_wpa_network_find(wpa, ssid);
-	if (id == -1)
-		id = dhcpcd_wpa_network_new(wpa);
+	if (id != -1)
+		return id;
+
+	dl = dhcpcd_decode_string_escape(dssid, sizeof(dssid), ssid);
+	if (dl == -1)
+		return -1;
+
+	for (i = 0; i < dl; i++) {
+		if (!isascii((int)dssid[i]) && !isprint((int)dssid[i]))
+			break;
+	}
+	dp = dssid;
+	ep = essid;
+	if (i < dl) {
+		/* Non standard characters found! Encode as hex string */
+		unsigned char c;
+
+		for (; dl; dl--) {
+			c = (unsigned char)*dp++;
+			*ep++ = hexchrs[(c & 0xf0) >> 4];
+			*ep++ = hexchrs[(c & 0x0f)];
+		}
+	} else {
+		*ep++ = '\"';
+		do
+			*ep++ = *dp;
+		while (*++dp != '\0');
+		*ep++ = '\"';
+	}
+	*ep = '\0';
+
+	id = dhcpcd_wpa_network_new(wpa);
+	if (id != -1)
+		dhcpcd_wpa_network_set(wpa, id, "ssid", essid);
 	return id;
 }
 
@@ -701,55 +1023,123 @@ dhcpcd_wpa_start(DHCPCD_CONNECTION *con)
 		dhcpcd_wpa_if_event(i);
 }
 
-int
-dhcpcd_wpa_configure_psk(DHCPCD_WPA *wpa, DHCPCD_WI_SCAN *s, const char *psk)
+static const char *
+dhcpcd_wpa_var_psk(DHCPCD_WI_SCAN *s)
+{
+
+	if (s->flags & WSF_WEP)
+		return "wep_key0";
+	else if ((s->flags & (WSF_WPA | WSF_PSK)) == (WSF_WPA | WSF_PSK))
+		return "psk";
+	return NULL;
+}
+
+static const char *
+dhcpcd_wpa_var_mgmt(DHCPCD_WI_SCAN *s)
+{
+
+	if (s->flags & WSF_WPA) {
+		if (s->flags & WSF_PSK)
+			return "WPA-PSK";
+	}
+	return "NONE";
+}
+
+static int
+dhcpcd_wpa_configure1(DHCPCD_WPA *wpa, DHCPCD_WI_SCAN *s, const char *psk)
 {
 	const char *mgmt, *var;
-	int id;
+	int id, retval;
 	char *npsk;
 	size_t psk_len;
 	bool r;
 
-	assert(wpa);
-	assert(s);
+	if (!dhcpcd_wpa_disconnect(wpa))
+		return DHCPCD_WPA_ERR_DISCONN;
+
+	/* reload the configuration so that when we don't save
+	 * the disabled networks to the config file. */
+	if (!dhcpcd_wpa_reconfigure(wpa))
+		return DHCPCD_WPA_ERR_RECONF;
 
 	id = dhcpcd_wpa_network_find_new(wpa, s->ssid);
 	if (id == -1)
 		return DHCPCD_WPA_ERR;
 
-	if (strcmp(s->flags, "[WEP]") == 0) {
-		mgmt = "NONE";
-		var = "wep_key0";
-	} else {
-		mgmt = "WPA-PSK";
-		var = "psk";
-	}
+	mgmt = dhcpcd_wpa_var_mgmt(s);
+	var = dhcpcd_wpa_var_psk(s);
+	if (mgmt && var) {
+		if (!dhcpcd_wpa_network_set(wpa, id, "key_mgmt", mgmt))
+			return DHCPCD_WPA_ERR_SET;
 
-	if (!dhcpcd_wpa_network_set(wpa, id, "key_mgmt", mgmt))
-		return DHCPCD_WPA_ERR_SET;
+		if (psk)
+			psk_len = strlen(psk);
+		else
+			psk_len = 0;
+		npsk = malloc(psk_len + 3);
+		if (npsk == NULL)
+			return DHCPCD_WPA_ERR;
+		npsk[0] = '"';
+		if (psk_len)
+			memcpy(npsk + 1, psk, psk_len);
+		npsk[psk_len + 1] = '"';
+		npsk[psk_len + 2] = '\0';
+		r = dhcpcd_wpa_network_set(wpa, id, var, npsk);
+		free(npsk);
+		if (!r)
+			return DHCPCD_WPA_ERR_SET_PSK;
+	}
 
-	if (psk)
-		psk_len = strlen(psk);
+	if (!dhcpcd_wpa_network_enable(wpa, id))
+		return DHCPCD_WPA_ERR_ENABLE;
+	if (dhcpcd_wpa_config_write(wpa))
+		retval = DHCPCD_WPA_SUCCESS;
 	else
-		psk_len = 0;
-	npsk = malloc(psk_len + 3);
-	if (npsk == NULL)
+		retval = DHCPCD_WPA_ERR_WRITE;
+	/* Selecting a network disbales the others.
+	 * This should not be saved. */
+	if (!dhcpcd_wpa_network_select(wpa, id))
+		return DHCPCD_WPA_ERR_SELECT;
+	return retval;
+}
+
+int
+dhcpcd_wpa_configure(DHCPCD_WPA *wpa, DHCPCD_WI_SCAN *s, const char *psk)
+{
+	int retval;
+
+	retval = dhcpcd_wpa_configure1(wpa, s, psk);
+	/* Always reassociate */
+	if (!dhcpcd_wpa_reassociate(wpa)) {
+		if (retval == DHCPCD_WPA_SUCCESS)
+			retval = DHCPCD_WPA_ERR_ASSOC;
+	}
+	return retval;
+}
+
+int
+dhcpcd_wpa_select(DHCPCD_WPA *wpa, DHCPCD_WI_SCAN *s)
+{
+	int id, retval;
+
+	assert(wpa);
+	assert(s);
+
+	id = dhcpcd_wpa_network_find(wpa, s->ssid);
+	if (id == -1)
 		return DHCPCD_WPA_ERR;
-	npsk[0] = '"';
-	if (psk_len)
-		memcpy(npsk + 1, psk, psk_len);
-	npsk[psk_len + 1] = '"';
-	npsk[psk_len + 2] = '\0';
-	r = dhcpcd_wpa_network_set(wpa, id, var, npsk);
-	free(npsk);
-	if (!r)
-		return DHCPCD_WPA_ERR_SET_PSK;
 
-	if (!dhcpcd_wpa_network_enable(wpa, id))
-		return DHCPCD_WPA_ERR_ENABLE;
-	if (!dhcpcd_wpa_reassociate(wpa))
-		return DHCPCD_WPA_ERR_ASSOC;
-	if (!dhcpcd_wpa_config_write(wpa))
-		return DHCPCD_WPA_ERR_WRITE;
-	return DHCPCD_WPA_SUCCESS;
+	if (!dhcpcd_wpa_disconnect(wpa))
+		retval = DHCPCD_WPA_ERR_DISCONN;
+	else if (!dhcpcd_wpa_network_select(wpa, id))
+		retval = DHCPCD_WPA_ERR_SELECT;
+	else
+		retval = DHCPCD_WPA_SUCCESS;
+
+	/* Always reassociate */
+	if (!dhcpcd_wpa_reassociate(wpa)) {
+		if (retval == DHCPCD_WPA_SUCCESS)
+			retval = DHCPCD_WPA_ERR_ASSOC;
+	}
+	return retval;
 }