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/wps/httpread.c b/src/wps/httpread.c
new file mode 100644
index 0000000..40422e4
--- /dev/null
+++ b/src/wps/httpread.c
@@ -0,0 +1,861 @@
+/*
+ * httpread - Manage reading file(s) from HTTP/TCP socket
+ * Author: Ted Merrill
+ * Copyright 2008 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.
+ *
+ * The files are buffered via internal callbacks from eloop, then presented to
+ * an application callback routine when completely read into memory. May also
+ * be used if no file is expected but just to get the header, including HTTP
+ * replies (e.g. HTTP/1.1 200 OK etc.).
+ *
+ * This does not attempt to be an optimally efficient implementation, but does
+ * attempt to be of reasonably small size and memory consumption; assuming that
+ * only small files are to be read. A maximum file size is provided by
+ * application and enforced.
+ *
+ * It is assumed that the application does not expect any of the following:
+ * -- transfer encoding other than chunked
+ * -- trailer fields
+ * It is assumed that, even if the other side requested that the connection be
+ * kept open, that we will close it (thus HTTP messages sent by application
+ * should have the connection closed field); this is allowed by HTTP/1.1 and
+ * simplifies things for us.
+ *
+ * Other limitations:
+ * -- HTTP header may not exceed a hard-coded size.
+ *
+ * Notes:
+ * This code would be massively simpler without some of the new features of
+ * HTTP/1.1, especially chunked data.
+ */
+
+#include "includes.h"
+
+#include "common.h"
+#include "eloop.h"
+#include "httpread.h"
+
+
+/* Tunable parameters */
+#define HTTPREAD_READBUF_SIZE 1024      /* read in chunks of this size */
+#define HTTPREAD_HEADER_MAX_SIZE 4096   /* max allowed for headers */
+#define HTTPREAD_BODYBUF_DELTA 4096     /* increase allocation by this */
+
+#if 0
+/* httpread_debug -- set this global variable > 0 e.g. from debugger
+ * to enable debugs (larger numbers for more debugs)
+ * Make this a #define of 0 to eliminate the debugging code.
+ */
+int httpread_debug = 99;
+#else
+#define httpread_debug 0        /* eliminates even the debugging code */
+#endif
+
+
+/* control instance -- actual definition (opaque to application)
+ */
+struct httpread {
+	/* information from creation */
+	int sd;         /* descriptor of TCP socket to read from */
+	void (*cb)(struct httpread *handle, void *cookie,
+		    enum httpread_event e);  /* call on event */
+	void *cookie;   /* pass to callback */
+	int max_bytes;          /* maximum file size else abort it */
+	int timeout_seconds;            /* 0 or total duration timeout period */
+
+	/* dynamically used information follows */
+	int sd_registered;      /* nonzero if we need to unregister socket */
+	int to_registered;      /* nonzero if we need to unregister timeout */
+
+	int got_hdr;            /* nonzero when header is finalized */
+	char hdr[HTTPREAD_HEADER_MAX_SIZE+1];   /* headers stored here */
+	int hdr_nbytes;
+
+	enum httpread_hdr_type hdr_type;
+	int version;            /* 1 if we've seen 1.1 */
+	int reply_code;         /* for type REPLY, e.g. 200 for HTTP/1.1 200 OK */
+	int got_content_length; /* true if we know content length for sure */
+	int content_length;     /* body length,  iff got_content_length */
+	int chunked;            /* nonzero for chunked data */
+	char *uri;
+
+	int got_body;           /* nonzero when body is finalized */
+	char *body;
+	int body_nbytes;
+	int body_alloc_nbytes;  /* amount allocated */
+
+	int got_file;           /* here when we are done */
+
+	/* The following apply if data is chunked: */
+	int in_chunk_data;      /* 0=in/at header, 1=in the data or tail*/
+	int chunk_start;        /* offset in body of chunk hdr or data */
+	int chunk_size;         /* data of chunk (not hdr or ending CRLF)*/
+	int in_trailer;         /* in header fields after data (chunked only)*/
+	enum trailer_state {
+		trailer_line_begin = 0,
+		trailer_empty_cr,       /* empty line + CR */
+		trailer_nonempty,
+		trailer_nonempty_cr,
+	} trailer_state;
+};
+
+
+/* Check words for equality, where words consist of graphical characters
+ * delimited by whitespace
+ * Returns nonzero if "equal" doing case insensitive comparison.
+ */
+static int word_eq(char *s1, char *s2)
+{
+	int c1;
+	int c2;
+	int end1 = 0;
+	int end2 = 0;
+	for (;;) {
+		c1 = *s1++;
+		c2 = *s2++;
+		if (isalpha(c1) && isupper(c1))
+			c1 = tolower(c1);
+		if (isalpha(c2) && isupper(c2))
+			c2 = tolower(c2);
+		end1 = !isgraph(c1);
+		end2 = !isgraph(c2);
+		if (end1 || end2 || c1 != c2)
+			break;
+	}
+	return end1 && end2;  /* reached end of both words? */
+}
+
+
+/* convert hex to binary
+ * Requires that c have been previously tested true with isxdigit().
+ */
+static int hex_value(int c)
+{
+	if (isdigit(c))
+		return c - '0';
+	if (islower(c))
+		return 10 + c - 'a';
+	return 10 + c - 'A';
+}
+
+
+static void httpread_timeout_handler(void *eloop_data, void *user_ctx);
+
+/* httpread_destroy -- if h is non-NULL, clean up
+ * This must eventually be called by the application following
+ * call of the application's callback and may be called
+ * earlier if desired.
+ */
+void httpread_destroy(struct httpread *h)
+{
+	if (httpread_debug >= 10)
+		wpa_printf(MSG_DEBUG, "ENTER httpread_destroy(%p)", h);
+	if (!h)
+		return;
+
+	if (h->to_registered)
+		eloop_cancel_timeout(httpread_timeout_handler, NULL, h);
+	h->to_registered = 0;
+	if (h->sd_registered)
+		eloop_unregister_sock(h->sd, EVENT_TYPE_READ);
+	h->sd_registered = 0;
+	os_free(h->body);
+	os_free(h->uri);
+	os_memset(h, 0, sizeof(*h));  /* aid debugging */
+	h->sd = -1;     /* aid debugging */
+	os_free(h);
+}
+
+
+/* httpread_timeout_handler -- called on excessive total duration
+ */
+static void httpread_timeout_handler(void *eloop_data, void *user_ctx)
+{
+	struct httpread *h = user_ctx;
+	wpa_printf(MSG_DEBUG, "httpread timeout (%p)", h);
+	h->to_registered = 0;   /* is self-cancelling */
+	(*h->cb)(h, h->cookie, HTTPREAD_EVENT_TIMEOUT);
+}
+
+
+/* Analyze options only so far as is needed to correctly obtain the file.
+ * The application can look at the raw header to find other options.
+ */
+static int httpread_hdr_option_analyze(
+	struct httpread *h,
+	char *hbp       /* pointer to current line in header buffer */
+	)
+{
+	if (word_eq(hbp, "CONTENT-LENGTH:")) {
+		while (isgraph(*hbp))
+			hbp++;
+		while (*hbp == ' ' || *hbp == '\t')
+			hbp++;
+		if (!isdigit(*hbp))
+			return -1;
+		h->content_length = atol(hbp);
+		h->got_content_length = 1;
+		return 0;
+	}
+	if (word_eq(hbp, "TRANSFER_ENCODING:") ||
+	    word_eq(hbp, "TRANSFER-ENCODING:")) {
+		while (isgraph(*hbp))
+			hbp++;
+		while (*hbp == ' ' || *hbp == '\t')
+			hbp++;
+		/* There should (?) be no encodings of interest
+		 * other than chunked...
+		 */
+		if (word_eq(hbp, "CHUNKED")) {
+			h->chunked = 1;
+			h->in_chunk_data = 0;
+			/* ignore possible ;<parameters> */
+		}
+		return 0;
+	}
+	/* skip anything we don't know, which is a lot */
+	return 0;
+}
+
+
+static int httpread_hdr_analyze(struct httpread *h)
+{
+	char *hbp = h->hdr;      /* pointer into h->hdr */
+	int standard_first_line = 1;
+
+	/* First line is special */
+	h->hdr_type = HTTPREAD_HDR_TYPE_UNKNOWN;
+	if (!isgraph(*hbp))
+		goto bad;
+	if (os_strncmp(hbp, "HTTP/", 5) == 0) {
+		h->hdr_type = HTTPREAD_HDR_TYPE_REPLY;
+		standard_first_line = 0;
+		hbp += 5;
+		if (hbp[0] == '1' && hbp[1] == '.' &&
+		    isdigit(hbp[2]) && hbp[2] != '0')
+			h->version = 1;
+		while (isgraph(*hbp))
+			hbp++;
+		while (*hbp == ' ' || *hbp == '\t')
+			hbp++;
+		if (!isdigit(*hbp))
+			goto bad;
+		h->reply_code = atol(hbp);
+	} else if (word_eq(hbp, "GET"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_GET;
+	else if (word_eq(hbp, "HEAD"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_HEAD;
+	else if (word_eq(hbp, "POST"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_POST;
+	else if (word_eq(hbp, "PUT"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_PUT;
+	else if (word_eq(hbp, "DELETE"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_DELETE;
+	else if (word_eq(hbp, "TRACE"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_TRACE;
+	else if (word_eq(hbp, "CONNECT"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_CONNECT;
+	else if (word_eq(hbp, "NOTIFY"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_NOTIFY;
+	else if (word_eq(hbp, "M-SEARCH"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_M_SEARCH;
+	else if (word_eq(hbp, "M-POST"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_M_POST;
+	else if (word_eq(hbp, "SUBSCRIBE"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_SUBSCRIBE;
+	else if (word_eq(hbp, "UNSUBSCRIBE"))
+		h->hdr_type = HTTPREAD_HDR_TYPE_UNSUBSCRIBE;
+	else {
+	}
+
+	if (standard_first_line) {
+		char *rawuri;
+		char *uri;
+		/* skip type */
+		while (isgraph(*hbp))
+			hbp++;
+		while (*hbp == ' ' || *hbp == '\t')
+			hbp++;
+		/* parse uri.
+		 * Find length, allocate memory for translated
+		 * copy, then translate by changing %<hex><hex>
+		 * into represented value.
+		 */
+		rawuri = hbp;
+		while (isgraph(*hbp))
+			hbp++;
+		h->uri = os_malloc((hbp - rawuri) + 1);
+		if (h->uri == NULL)
+			goto bad;
+		uri = h->uri;
+		while (rawuri < hbp) {
+			int c = *rawuri;
+			if (c == '%' &&
+			    isxdigit(rawuri[1]) && isxdigit(rawuri[2])) {
+				*uri++ = (hex_value(rawuri[1]) << 4) |
+					hex_value(rawuri[2]);
+				rawuri += 3;
+			} else {
+				*uri++ = c;
+				rawuri++;
+			}
+		}
+		*uri = 0;       /* null terminate */
+		while (isgraph(*hbp))
+			hbp++;
+		while (*hbp == ' ' || *hbp == '\t')
+			hbp++;
+		/* get version */
+		if (0 == strncmp(hbp, "HTTP/", 5)) {
+			hbp += 5;
+			if (hbp[0] == '1' && hbp[1] == '.' &&
+			    isdigit(hbp[2]) && hbp[2] != '0')
+				h->version = 1;
+		}
+	}
+	/* skip rest of line */
+	while (*hbp)
+		if (*hbp++ == '\n')
+			break;
+
+	/* Remainder of lines are options, in any order;
+	 * or empty line to terminate
+	 */
+	for (;;) {
+		/* Empty line to terminate */
+		if (hbp[0] == '\n' ||
+		    (hbp[0] == '\r' && hbp[1] == '\n'))
+			break;
+		if (!isgraph(*hbp))
+			goto bad;
+		if (httpread_hdr_option_analyze(h, hbp))
+			goto bad;
+		/* skip line */
+		while (*hbp)
+			if (*hbp++ == '\n')
+				break;
+	}
+
+	/* chunked overrides content-length always */
+	if (h->chunked)
+		h->got_content_length = 0;
+
+	/* For some types, we should not try to read a body
+	 * This is in addition to the application determining
+	 * that we should not read a body.
+	 */
+	switch (h->hdr_type) {
+	case HTTPREAD_HDR_TYPE_REPLY:
+		/* Some codes can have a body and some not.
+		 * For now, just assume that any other than 200
+		 * do not...
+		 */
+		if (h->reply_code != 200)
+			h->max_bytes = 0;
+		break;
+	case HTTPREAD_HDR_TYPE_GET:
+	case HTTPREAD_HDR_TYPE_HEAD:
+		/* in practice it appears that it is assumed
+		 * that GETs have a body length of 0... ?
+		 */
+		if (h->chunked == 0 && h->got_content_length == 0)
+			h->max_bytes = 0;
+		break;
+	case HTTPREAD_HDR_TYPE_POST:
+	case HTTPREAD_HDR_TYPE_PUT:
+	case HTTPREAD_HDR_TYPE_DELETE:
+	case HTTPREAD_HDR_TYPE_TRACE:
+	case HTTPREAD_HDR_TYPE_CONNECT:
+	case HTTPREAD_HDR_TYPE_NOTIFY:
+	case HTTPREAD_HDR_TYPE_M_SEARCH:
+	case HTTPREAD_HDR_TYPE_M_POST:
+	case HTTPREAD_HDR_TYPE_SUBSCRIBE:
+	case HTTPREAD_HDR_TYPE_UNSUBSCRIBE:
+	default:
+		break;
+	}
+
+	return 0;
+
+bad:
+	/* Error */
+	return -1;
+}
+
+
+/* httpread_read_handler -- called when socket ready to read
+ *
+ * Note: any extra data we read past end of transmitted file is ignored;
+ * if we were to support keeping connections open for multiple files then
+ * this would have to be addressed.
+ */
+static void httpread_read_handler(int sd, void *eloop_ctx, void *sock_ctx)
+{
+	struct httpread *h = sock_ctx;
+	int nread;
+	char *rbp;      /* pointer into read buffer */
+	char *hbp;      /* pointer into header buffer */
+	char *bbp;      /* pointer into body buffer */
+	char readbuf[HTTPREAD_READBUF_SIZE];  /* temp use to read into */
+
+	if (httpread_debug >= 20)
+		wpa_printf(MSG_DEBUG, "ENTER httpread_read_handler(%p)", h);
+
+	/* read some at a time, then search for the interal
+	 * boundaries between header and data and etc.
+	 */
+	nread = read(h->sd, readbuf, sizeof(readbuf));
+	if (nread < 0)
+		goto bad;
+	if (nread == 0) {
+		/* end of transmission... this may be normal
+		 * or may be an error... in some cases we can't
+		 * tell which so we must assume it is normal then.
+		 */
+		if (!h->got_hdr) {
+			/* Must at least have completed header */
+			wpa_printf(MSG_DEBUG, "httpread premature eof(%p)", h);
+			goto bad;
+		}
+		if (h->chunked || h->got_content_length) {
+			/* Premature EOF; e.g. dropped connection */
+			wpa_printf(MSG_DEBUG,
+				   "httpread premature eof(%p) %d/%d",
+				   h, h->body_nbytes,
+				   h->content_length);
+			goto bad;
+		}
+		/* No explicit length, hopefully we have all the data
+		 * although dropped connections can cause false
+		 * end
+		 */
+		if (httpread_debug >= 10)
+			wpa_printf(MSG_DEBUG, "httpread ok eof(%p)", h);
+			h->got_body = 1;
+			goto got_file;
+	}
+	rbp = readbuf;
+
+	/* Header consists of text lines (terminated by both CR and LF)
+	 * and an empty line (CR LF only).
+	 */
+	if (!h->got_hdr) {
+		hbp = h->hdr + h->hdr_nbytes;
+		/* add to headers until:
+		 *      -- we run out of data in read buffer
+		 *      -- or, we run out of header buffer room
+		 *      -- or, we get double CRLF in headers
+		 */
+		for (;;) {
+			if (nread == 0)
+				goto get_more;
+			if (h->hdr_nbytes == HTTPREAD_HEADER_MAX_SIZE) {
+				goto bad;
+			}
+			*hbp++ = *rbp++;
+			nread--;
+			h->hdr_nbytes++;
+			if (h->hdr_nbytes >= 4 &&
+			    hbp[-1] == '\n' &&
+			    hbp[-2] == '\r' &&
+			    hbp[-3] == '\n' &&
+			    hbp[-4] == '\r' ) {
+				h->got_hdr = 1;
+				*hbp = 0;       /* null terminate */
+				break;
+			}
+		}
+		/* here we've just finished reading the header */
+		if (httpread_hdr_analyze(h)) {
+			wpa_printf(MSG_DEBUG, "httpread bad hdr(%p)", h);
+			goto bad;
+		}
+		if (h->max_bytes == 0) {
+			if (httpread_debug >= 10)
+				wpa_printf(MSG_DEBUG,
+					   "httpread no body hdr end(%p)", h);
+			goto got_file;
+		}
+		if (h->got_content_length && h->content_length == 0) {
+			if (httpread_debug >= 10)
+				wpa_printf(MSG_DEBUG,
+					   "httpread zero content length(%p)",
+					   h);
+			goto got_file;
+		}
+	}
+
+	/* Certain types of requests never have data and so
+	 * must be specially recognized.
+	 */
+	if (!os_strncasecmp(h->hdr, "SUBSCRIBE", 9) ||
+	    !os_strncasecmp(h->hdr, "UNSUBSCRIBE", 11) ||
+	    !os_strncasecmp(h->hdr, "HEAD", 4) ||
+	    !os_strncasecmp(h->hdr, "GET", 3)) {
+		if (!h->got_body) {
+			if (httpread_debug >= 10)
+				wpa_printf(MSG_DEBUG,
+					   "httpread NO BODY for sp. type");
+		}
+		h->got_body = 1;
+		goto got_file;
+	}
+
+	/* Data can be just plain binary data, or if "chunked"
+	 * consists of chunks each with a header, ending with
+	 * an ending header.
+	 */
+	if (nread == 0)
+		goto get_more;
+	if (!h->got_body) {
+		/* Here to get (more of) body */
+		/* ensure we have enough room for worst case for body
+		 * plus a null termination character
+		 */
+		if (h->body_alloc_nbytes < (h->body_nbytes + nread + 1)) {
+			char *new_body;
+			int new_alloc_nbytes;
+
+			if (h->body_nbytes >= h->max_bytes)
+				goto bad;
+			new_alloc_nbytes = h->body_alloc_nbytes +
+				HTTPREAD_BODYBUF_DELTA;
+			/* For content-length case, the first time
+			 * through we allocate the whole amount
+			 * we need.
+			 */
+			if (h->got_content_length &&
+			    new_alloc_nbytes < (h->content_length + 1))
+				new_alloc_nbytes = h->content_length + 1;
+			if ((new_body = os_realloc(h->body, new_alloc_nbytes))
+			    == NULL)
+				goto bad;
+
+			h->body = new_body;
+			h->body_alloc_nbytes = new_alloc_nbytes;
+		}
+		/* add bytes */
+		bbp = h->body + h->body_nbytes;
+		for (;;) {
+			int ncopy;
+			/* See if we need to stop */
+			if (h->chunked && h->in_chunk_data == 0) {
+				/* in chunk header */
+				char *cbp = h->body + h->chunk_start;
+				if (bbp-cbp >= 2 && bbp[-2] == '\r' &&
+				    bbp[-1] == '\n') {
+					/* end of chunk hdr line */
+					/* hdr line consists solely
+					 * of a hex numeral and CFLF
+					 */
+					if (!isxdigit(*cbp))
+						goto bad;
+					h->chunk_size = strtoul(cbp, NULL, 16);
+					/* throw away chunk header
+					 * so we have only real data
+					 */
+					h->body_nbytes = h->chunk_start;
+					bbp = cbp;
+					if (h->chunk_size == 0) {
+						/* end of chunking */
+						/* trailer follows */
+						h->in_trailer = 1;
+						if (httpread_debug >= 20)
+							wpa_printf(
+								MSG_DEBUG,
+								"httpread end chunks(%p)", h);
+						break;
+					}
+					h->in_chunk_data = 1;
+					/* leave chunk_start alone */
+				}
+			} else if (h->chunked) {
+				/* in chunk data */
+				if ((h->body_nbytes - h->chunk_start) ==
+				    (h->chunk_size + 2)) {
+					/* end of chunk reached,
+					 * new chunk starts
+					 */
+					/* check chunk ended w/ CRLF
+					 * which we'll throw away
+					 */
+					if (bbp[-1] == '\n' &&
+					    bbp[-2] == '\r') {
+					} else
+						goto bad;
+					h->body_nbytes -= 2;
+					bbp -= 2;
+					h->chunk_start = h->body_nbytes;
+					h->in_chunk_data = 0;
+					h->chunk_size = 0; /* just in case */
+				}
+			} else if (h->got_content_length &&
+				   h->body_nbytes >= h->content_length) {
+				h->got_body = 1;
+				if (httpread_debug >= 10)
+					wpa_printf(
+						MSG_DEBUG,
+						"httpread got content(%p)", h);
+				goto got_file;
+			}
+			if (nread <= 0)
+				break;
+			/* Now transfer. Optimize using memcpy where we can. */
+			if (h->chunked && h->in_chunk_data) {
+				/* copy up to remainder of chunk data
+				 * plus the required CR+LF at end
+				 */
+				ncopy = (h->chunk_start + h->chunk_size + 2) -
+					h->body_nbytes;
+			} else if (h->chunked) {
+				/*in chunk header -- don't optimize */
+				*bbp++ = *rbp++;
+				nread--;
+				h->body_nbytes++;
+				continue;
+			} else if (h->got_content_length) {
+				ncopy = h->content_length - h->body_nbytes;
+			} else {
+				ncopy = nread;
+			}
+			/* Note: should never be 0 */
+			if (ncopy > nread)
+				ncopy = nread;
+			os_memcpy(bbp, rbp, ncopy);
+			bbp += ncopy;
+			h->body_nbytes += ncopy;
+			rbp += ncopy;
+			nread -= ncopy;
+		}       /* body copy loop */
+	}       /* !got_body */
+	if (h->chunked && h->in_trailer) {
+		/* If "chunked" then there is always a trailer,
+		 * consisting of zero or more non-empty lines
+		 * ending with CR LF and then an empty line w/ CR LF.
+		 * We do NOT support trailers except to skip them --
+		 * this is supported (generally) by the http spec.
+		 */
+		bbp = h->body + h->body_nbytes;
+		for (;;) {
+			int c;
+			if (nread <= 0)
+				break;
+			c = *rbp++;
+			nread--;
+			switch (h->trailer_state) {
+			case trailer_line_begin:
+				if (c == '\r')
+					h->trailer_state = trailer_empty_cr;
+				else
+					h->trailer_state = trailer_nonempty;
+				break;
+			case trailer_empty_cr:
+				/* end empty line */
+				if (c == '\n') {
+					h->trailer_state = trailer_line_begin;
+					h->in_trailer = 0;
+					if (httpread_debug >= 10)
+						wpa_printf(
+							MSG_DEBUG,
+							"httpread got content(%p)", h);
+					h->got_body = 1;
+					goto got_file;
+				}
+				h->trailer_state = trailer_nonempty;
+				break;
+			case trailer_nonempty:
+				if (c == '\r')
+					h->trailer_state = trailer_nonempty_cr;
+				break;
+			case trailer_nonempty_cr:
+				if (c == '\n')
+					h->trailer_state = trailer_line_begin;
+				else
+					h->trailer_state = trailer_nonempty;
+				break;
+			}
+		}
+	}
+	goto get_more;
+
+bad:
+	/* Error */
+	wpa_printf(MSG_DEBUG, "httpread read/parse failure (%p)", h);
+	(*h->cb)(h, h->cookie, HTTPREAD_EVENT_ERROR);
+	return;
+
+get_more:
+	return;
+
+got_file:
+	if (httpread_debug >= 10)
+		wpa_printf(MSG_DEBUG,
+			   "httpread got file %d bytes type %d",
+			   h->body_nbytes, h->hdr_type);
+	/* Null terminate for convenience of some applications */
+	if (h->body)
+		h->body[h->body_nbytes] = 0; /* null terminate */
+	h->got_file = 1;
+	/* Assume that we do NOT support keeping connection alive,
+	 * and just in case somehow we don't get destroyed right away,
+	 * unregister now.
+	 */
+	if (h->sd_registered)
+		eloop_unregister_sock(h->sd, EVENT_TYPE_READ);
+	h->sd_registered = 0;
+	/* The application can destroy us whenever they feel like...
+	 * cancel timeout.
+	 */
+	if (h->to_registered)
+		eloop_cancel_timeout(httpread_timeout_handler, NULL, h);
+	h->to_registered = 0;
+	(*h->cb)(h, h->cookie, HTTPREAD_EVENT_FILE_READY);
+}
+
+
+/* httpread_create -- start a new reading session making use of eloop.
+ * The new instance will use the socket descriptor for reading (until
+ * it gets a file and not after) but will not close the socket, even
+ * when the instance is destroyed (the application must do that).
+ * Return NULL on error.
+ *
+ * Provided that httpread_create successfully returns a handle,
+ * the callback fnc is called to handle httpread_event events.
+ * The caller should do destroy on any errors or unknown events.
+ *
+ * Pass max_bytes == 0 to not read body at all (required for e.g.
+ * reply to HEAD request).
+ */
+struct httpread * httpread_create(
+	int sd,	 /* descriptor of TCP socket to read from */
+	void (*cb)(struct httpread *handle, void *cookie,
+		   enum httpread_event e),  /* call on event */
+	void *cookie,    /* pass to callback */
+	int max_bytes,	  /* maximum body size else abort it */
+	int timeout_seconds     /* 0; or total duration timeout period */
+	)
+{
+	struct httpread *h = NULL;
+
+	h = os_zalloc(sizeof(*h));
+	if (h == NULL)
+		goto fail;
+	h->sd = sd;
+	h->cb = cb;
+	h->cookie = cookie;
+	h->max_bytes = max_bytes;
+	h->timeout_seconds = timeout_seconds;
+
+	if (timeout_seconds > 0) {
+		if (eloop_register_timeout(timeout_seconds, 0,
+					   httpread_timeout_handler,
+					   NULL, h)) {
+			/* No way to recover (from malloc failure) */
+			goto fail;
+		}
+		h->to_registered = 1;
+	}
+	if (eloop_register_sock(sd, EVENT_TYPE_READ, httpread_read_handler,
+				NULL, h)) {
+		/* No way to recover (from malloc failure) */
+		goto fail;
+	}
+	h->sd_registered = 1;
+	return h;
+
+fail:
+
+	/* Error */
+	httpread_destroy(h);
+	return NULL;
+}
+
+
+/* httpread_hdr_type_get -- When file is ready, returns header type. */
+enum httpread_hdr_type httpread_hdr_type_get(struct httpread *h)
+{
+	return h->hdr_type;
+}
+
+
+/* httpread_uri_get -- When file is ready, uri_get returns (translated) URI
+ * or possibly NULL (which would be an error).
+ */
+char * httpread_uri_get(struct httpread *h)
+{
+	return h->uri;
+}
+
+
+/* httpread_reply_code_get -- When reply is ready, returns reply code */
+int httpread_reply_code_get(struct httpread *h)
+{
+	return h->reply_code;
+}
+
+
+/* httpread_length_get -- When file is ready, returns file length. */
+int httpread_length_get(struct httpread *h)
+{
+	return h->body_nbytes;
+}
+
+
+/* httpread_data_get -- When file is ready, returns file content
+ * with null byte appened.
+ * Might return NULL in some error condition.
+ */
+void * httpread_data_get(struct httpread *h)
+{
+	return h->body ? h->body : "";
+}
+
+
+/* httpread_hdr_get -- When file is ready, returns header content
+ * with null byte appended.
+ * Might return NULL in some error condition.
+ */
+char * httpread_hdr_get(struct httpread *h)
+{
+	return h->hdr;
+}
+
+
+/* httpread_hdr_line_get -- When file is ready, returns pointer
+ * to line within header content matching the given tag
+ * (after the tag itself and any spaces/tabs).
+ *
+ * The tag should end with a colon for reliable matching.
+ *
+ * If not found, returns NULL;
+ */
+char * httpread_hdr_line_get(struct httpread *h, const char *tag)
+{
+	int tag_len = os_strlen(tag);
+	char *hdr = h->hdr;
+	hdr = os_strchr(hdr, '\n');
+	if (hdr == NULL)
+		return NULL;
+	hdr++;
+	for (;;) {
+		if (!os_strncasecmp(hdr, tag, tag_len)) {
+			hdr += tag_len;
+			while (*hdr == ' ' || *hdr == '\t')
+				hdr++;
+			return hdr;
+		}
+		hdr = os_strchr(hdr, '\n');
+		if (hdr == NULL)
+			return NULL;
+		hdr++;
+	}
+}