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GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.sbin/iscsid/pdu.c	Lines:	0	191	0.0 %
Date:	2017-11-13	Branches:	0	148	0.0 %


/*	$OpenBSD: pdu.c,v 1.11 2015/12/05 06:38:18 mmcc Exp $ */

/*
 * Copyright (c) 2009 Claudio Jeker <claudio@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/uio.h>

#include <scsi/iscsi.h>

#include <errno.h>
#include <event.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "iscsid.h"
#include "log.h"

size_t	pdu_readbuf_read(struct pdu_readbuf *, void *, size_t);
size_t	pdu_readbuf_len(struct pdu_readbuf *);

#define PDU_MIN(_x, _y)		((_x) < (_y) ? (_x) : (_y))

void *
pdu_gethdr(struct pdu *p)
{
	void *hdr;

	if (!(hdr = calloc(1, sizeof(struct iscsi_pdu))))
		return NULL;
	if (pdu_addbuf(p, hdr, sizeof(struct iscsi_pdu), PDU_HEADER)) {
		free(hdr);
		return NULL;
	}
	return hdr;
}

int
text_to_pdu(struct kvp *k, struct pdu *p)
{
	char *buf, *s;
	size_t	len = 0, rem;
	int n, nk;

	if (k == NULL)
		return 0;

	nk = 0;
	while(k[nk].key) {
		len += 2 + strlen(k[nk].key) + strlen(k[nk].value);
		nk++;
	}

	if (!(buf = pdu_alloc(len)))
		return -1;
	s = buf;
	rem = len;
	nk = 0;
	while(k[nk].key) {
		n = snprintf(s, rem, "%s=%s", k[nk].key, k[nk].value);
		if (n == -1 || (size_t)n >= rem)
			fatalx("text_to_pdu");
		rem -= n + 1;
		s += n + 1;
		nk++;
	}

	if (pdu_addbuf(p, buf, len, PDU_DATA))
		return -1;
	return len;
}

struct kvp *
pdu_to_text(char *buf, size_t len)
{
	struct kvp *k;
	size_t n;
	char *eq;
	unsigned int nkvp = 0, i;

	/* remove padding zeros */
	for (n = len; n > 0 && buf[n - 1] == '\0'; n--)
		;
	if (n == len) {
		log_debug("pdu_to_text: badly terminated text data");
		return NULL;
	}
	len = n + 1;

	for(n = 0; n < len; n++)
		if (buf[n] == '\0')
			nkvp++;

	if (!(k = calloc(nkvp + 1, sizeof(*k))))
		return NULL;

	for (i = 0; i < nkvp; i++) {
		eq = strchr(buf, '=');
		if (!eq) {
			log_debug("pdu_to_text: badly encoded text data");
			free(k);
			return NULL;
		}
		*eq++ = '\0';
		k[i].key = buf;
		k[i].value = eq;
		buf = eq + strlen(eq) + 1;
	}
	return k;
}

/* Modified version of strtonum() to fit iscsid's need
 *
 * Copyright (c) 2004 Ted Unangst and Todd Miller
 * All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
u_int64_t
text_to_num(const char *numstr, u_int64_t minval, u_int64_t maxval,
    const char **errstrp)
{
	unsigned long long ull = 0;
	char *ep;
	int error = 0;
	struct errval {
		const char *errstr;
		int err;
	} ev[4] = {
		{ NULL,		0 },
		{ "invalid",	EINVAL },
		{ "too small",  ERANGE },
		{ "too large",	ERANGE }
	};
#define INVALID		1
#define TOOSMALL	2
#define TOOLARGE	3

	ev[0].err = errno;
	errno = 0;
	if (minval > maxval)
		error = INVALID;
	else {
		ull = strtoull(numstr, &ep, 0);
		if (numstr == ep || *ep != '\0')
			error = INVALID;
		else if (ull < minval)
			error = TOOSMALL;
		else if ((ull == ULLONG_MAX && errno == ERANGE) || ull > maxval)
			error = TOOLARGE;
	}
	if (errstrp != NULL)
		*errstrp = ev[error].errstr;
	errno = ev[error].err;
	if (error)
		ull = 0;

	return ull;
#undef INVALID
#undef TOOSMALL
#undef TOOLARGE
}

int
text_to_bool(const char *buf, const char **errstrp)
{
	int val = 0;

	if (!strcmp(buf, "Yes")) {
		val = 1;
		errno = 0;
	} else if (!strcmp(buf, "No"))
		errno = 0;
	else
		errno = EINVAL;

	if (errstrp != NULL) {
		if (errno == 0)
			*errstrp = NULL;
		else
			*errstrp = "invalid";
	}
	return val;
}


/*
 * Internal functions to send/recv pdus.
 */

void
pdu_free_queue(struct pduq *channel)
{
	struct pdu *p;

	while ((p = TAILQ_FIRST(channel))) {
		TAILQ_REMOVE(channel, p, entry);
		pdu_free(p);
	}
}

ssize_t
pdu_read(struct connection *c)
{
	struct iovec iov[2];
	unsigned int niov = 1;
	ssize_t n;

	bzero(&iov, sizeof(iov));
	iov[0].iov_base = c->prbuf.buf + c->prbuf.wpos;
	if (c->prbuf.wpos < c->prbuf.rpos)
		iov[0].iov_len = c->prbuf.rpos - c->prbuf.wpos;
	else {
		iov[0].iov_len = c->prbuf.size - c->prbuf.wpos;
		if (c->prbuf.rpos > 0) {
			niov++;
			iov[1].iov_base = c->prbuf.buf;
			iov[1].iov_len = c->prbuf.rpos - 1;
		}
	}

	if ((n = readv(c->fd, iov, niov)) == -1)
		return -1;
	if (n == 0)
		/* XXX what should we do on close with remaining data? */
		return 0;

	c->prbuf.wpos += n;
	if (c->prbuf.wpos >= c->prbuf.size)
		c->prbuf.wpos -= c->prbuf.size;

	return n;
}

ssize_t
pdu_write(struct connection *c)
{
	struct iovec iov[PDU_WRIOV];
	struct pdu *b, *nb;
	unsigned int niov = 0, j;
	size_t off, resid, size;
	ssize_t n;

	TAILQ_FOREACH(b, &c->pdu_w, entry) {
		if (niov >= PDU_WRIOV)
			break;
		off = b->resid;
		for (j = 0; j < PDU_MAXIOV && niov < PDU_WRIOV; j++) {
			if (!b->iov[j].iov_len)
				continue;
			if (off >= b->iov[j].iov_len) {
				off -= b->iov[j].iov_len;
				continue;
			}
			iov[niov].iov_base = (char *)b->iov[j].iov_base + off;
			iov[niov++].iov_len = b->iov[j].iov_len - off;
			off = 0;
		}
	}

	if ((n = writev(c->fd, iov, niov)) == -1) {
		if (errno == EAGAIN || errno == ENOBUFS ||
		    errno == EINTR)     /* try later */
			return 0;
		else {
			log_warn("pdu_write");
			return -1;
		}
	}
	if (n == 0)
		return 0;

	size = n;
        for (b = TAILQ_FIRST(&c->pdu_w); b != NULL && size > 0; b = nb) {
		nb = TAILQ_NEXT(b, entry);
		resid = b->resid;
		for (j = 0; j < PDU_MAXIOV; j++) {
			if (resid >= b->iov[j].iov_len)
				resid -= b->iov[j].iov_len;
			else if (size >= b->iov[j].iov_len - resid) {
				size -= b->iov[j].iov_len - resid;
				b->resid += b->iov[j].iov_len - resid;
				resid = 0;
			} else {
				b->resid += size;
				size = 0;
				break;
			}
		}
		if (j == PDU_MAXIOV) {
			/* all written */
			TAILQ_REMOVE(&c->pdu_w, b, entry);
			pdu_free(b);
		}
	}
	return n;
}

int
pdu_pending(struct connection *c)
{
	if (TAILQ_EMPTY(&c->pdu_w))
		return 0;
	else
		return 1;
}

void
pdu_parse(struct connection *c)
{
	struct pdu *p;
	struct iscsi_pdu *ipdu;
	char *ahb, *db;
	size_t ahslen, dlen, off;
	ssize_t n;
	unsigned int j;

/* XXX XXX I DON'T LIKE YOU. CAN I REWRITE YOU? */

	do {
		if (!(p = c->prbuf.wip)) {
			/* get and parse base header */
			if (pdu_readbuf_len(&c->prbuf) < sizeof(*ipdu))
				return;
			if (!(p = pdu_new()))
				goto fail;
			if (!(ipdu = pdu_gethdr(p)))
				goto fail;

			c->prbuf.wip = p;
			/*
			 * XXX maybe a pdu_readbuf_peek() would allow a better
			 * error handling.
			 */
			pdu_readbuf_read(&c->prbuf, ipdu, sizeof(*ipdu));

			ahslen = ipdu->ahslen * sizeof(u_int32_t);
			if (ahslen != 0) {
				if (!(ahb = pdu_alloc(ahslen)) ||
				    pdu_addbuf(p, ahb, ahslen, PDU_AHS))
					goto fail;
			}

			dlen = ipdu->datalen[0] << 16 | ipdu->datalen[1] << 8 |
			    ipdu->datalen[2];
			if (dlen != 0) {
				if (!(db = pdu_alloc(dlen)) ||
				    pdu_addbuf(p, db, dlen, PDU_DATA))
					goto fail;
			}

			p->resid = sizeof(*ipdu);
		} else {
			off = p->resid;
			for (j = 0; j < PDU_MAXIOV; j++) {
				if (off >= p->iov[j].iov_len)
					off -=  p->iov[j].iov_len;
				else {
					n = pdu_readbuf_read(&c->prbuf,
					    (char *)p->iov[j].iov_base + off,
					     p->iov[j].iov_len - off);
					p->resid += n;
					if (n == 0 || off + n !=
					    p->iov[j].iov_len)
						return;
				}
			}
			p->resid = 0; /* reset resid so pdu can be reused */
			c->prbuf.wip = NULL;
			task_pdu_cb(c, p);
		}
	} while (1);
fail:
	fatalx("pdu_parse hit a space oddity");
}

size_t
pdu_readbuf_read(struct pdu_readbuf *rb, void *ptr, size_t len)
{
	size_t l;

	if (rb->rpos == rb->wpos) {
		return 0;
	} else if (rb->rpos < rb->wpos) {
		l = PDU_MIN(rb->wpos - rb->rpos, len);
		memcpy(ptr, rb->buf + rb->rpos, l);
		rb->rpos += l;
		return l;
	} else {
		l = PDU_MIN(rb->size - rb->rpos, len);
		memcpy(ptr, rb->buf + rb->rpos, l);
		rb->rpos += l;
		if (rb->rpos == rb->size)
			rb->rpos = 0;
		if (l < len)
			return l + pdu_readbuf_read(rb, (char *)ptr + l,
			    len - l);
		return l;
	}
}

size_t
pdu_readbuf_len(struct pdu_readbuf *rb)
{
	if (rb->rpos <= rb->wpos)
		return rb->wpos - rb->rpos;
	else
		return rb->size - (rb->rpos - rb->wpos);
}

int
pdu_readbuf_set(struct pdu_readbuf *rb, size_t bsize)
{
	char *nb;

	if (bsize < rb->size)
		/* can't shrink */
		return 0;
	if ((nb = realloc(rb->buf, bsize)) == NULL) {
		free(rb->buf);
		return -1;
	}
	rb->buf = nb;
	rb->size = bsize;
	return 0;
}

void
pdu_readbuf_free(struct pdu_readbuf *rb)
{
	free(rb->buf);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: pdu.c,v 1.11 2015/12/05 06:38:18 mmcc Exp $ */
2
3			/*
4			* Copyright (c) 2009 Claudio Jeker <claudio@openbsd.org>
5			*
6			* Permission to use, copy, modify, and distribute this software for any
7			* purpose with or without fee is hereby granted, provided that the above
8			* copyright notice and this permission notice appear in all copies.
9			*
10			* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11			* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12			* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13			* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14			* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15			* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16			* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17			*/
18			#include <sys/types.h>
19			#include <sys/queue.h>
20			#include <sys/socket.h>
21			#include <sys/uio.h>
22
23			#include <scsi/iscsi.h>
24
25			#include <errno.h>
26			#include <event.h>
27			#include <limits.h>
28			#include <stdio.h>
29			#include <stdlib.h>
30			#include <string.h>
31			#include <unistd.h>
32
33			#include "iscsid.h"
34			#include "log.h"
35
36			size_t pdu_readbuf_read(struct pdu_readbuf , void , size_t);
37			size_t pdu_readbuf_len(struct pdu_readbuf *);
38
39			#define PDU_MIN(_x, _y) ((_x) < (_y) ? (_x) : (_y))
40
41			void *
42			pdu_gethdr(struct pdu *p)
43			{
44			void *hdr;
45
46			if (!(hdr = calloc(1, sizeof(struct iscsi_pdu))))
47			return NULL;
48			if (pdu_addbuf(p, hdr, sizeof(struct iscsi_pdu), PDU_HEADER)) {
49			free(hdr);
50			return NULL;
51			}
52			return hdr;
53			}
54
55			int
56			text_to_pdu(struct kvp k, struct pdu p)
57			{
58			char buf, s;
59			size_t len = 0, rem;
60			int n, nk;
61
62			if (k == NULL)
63			return 0;
64
65			nk = 0;
66			while(k[nk].key) {
67			len += 2 + strlen(k[nk].key) + strlen(k[nk].value);
68			nk++;
69			}
70
71			if (!(buf = pdu_alloc(len)))
72			return -1;
73			s = buf;
74			rem = len;
75			nk = 0;
76			while(k[nk].key) {
77			n = snprintf(s, rem, "%s=%s", k[nk].key, k[nk].value);
78			if (n == -1 \|\| (size_t)n >= rem)
79			fatalx("text_to_pdu");
80			rem -= n + 1;
81			s += n + 1;
82			nk++;
83			}
84
85			if (pdu_addbuf(p, buf, len, PDU_DATA))
86			return -1;
87			return len;
88			}
89
90			struct kvp *
91			pdu_to_text(char *buf, size_t len)
92			{
93			struct kvp *k;
94			size_t n;
95			char *eq;
96			unsigned int nkvp = 0, i;
97
98			/* remove padding zeros */
99			for (n = len; n > 0 && buf[n - 1] == '\0'; n--)
100			;
101			if (n == len) {
102			log_debug("pdu_to_text: badly terminated text data");
103			return NULL;
104			}
105			len = n + 1;
106
107			for(n = 0; n < len; n++)
108			if (buf[n] == '\0')
109			nkvp++;
110
111			if (!(k = calloc(nkvp + 1, sizeof(*k))))
112			return NULL;
113
114			for (i = 0; i < nkvp; i++) {
115			eq = strchr(buf, '=');
116			if (!eq) {
117			log_debug("pdu_to_text: badly encoded text data");
118			free(k);
119			return NULL;
120			}
121			*eq++ = '\0';
122			k[i].key = buf;
123			k[i].value = eq;
124			buf = eq + strlen(eq) + 1;
125			}
126			return k;
127			}
128
129			/* Modified version of strtonum() to fit iscsid's need
130			*
131			* Copyright (c) 2004 Ted Unangst and Todd Miller
132			* All rights reserved.
133			*
134			* Permission to use, copy, modify, and distribute this software for any
135			* purpose with or without fee is hereby granted, provided that the above
136			* copyright notice and this permission notice appear in all copies.
137			*
138			* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
139			* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
140			* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
141			* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
142			* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
143			* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
144			* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
145			*/
146			u_int64_t
147			text_to_num(const char *numstr, u_int64_t minval, u_int64_t maxval,
148			const char **errstrp)
149			{
150			unsigned long long ull = 0;
151			char *ep;
152			int error = 0;
153			struct errval {
154			const char *errstr;
155			int err;
156			} ev[4] = {
157			{ NULL, 0 },
158			{ "invalid", EINVAL },
159			{ "too small", ERANGE },
160			{ "too large", ERANGE }
161			};
162			#define INVALID 1
163			#define TOOSMALL 2
164			#define TOOLARGE 3
165
166			ev[0].err = errno;
167			errno = 0;
168			if (minval > maxval)
169			error = INVALID;
170			else {
171			ull = strtoull(numstr, &ep, 0);
172			if (numstr == ep \|\| *ep != '\0')
173			error = INVALID;
174			else if (ull < minval)
175			error = TOOSMALL;
176			else if ((ull == ULLONG_MAX && errno == ERANGE) \|\| ull > maxval)
177			error = TOOLARGE;
178			}
179			if (errstrp != NULL)
180			*errstrp = ev[error].errstr;
181			errno = ev[error].err;
182			if (error)
183			ull = 0;
184
185			return ull;
186			#undef INVALID
187			#undef TOOSMALL
188			#undef TOOLARGE
189			}
190
191			int
192			text_to_bool(const char buf, const char *errstrp)
193			{
194			int val = 0;
195
196			if (!strcmp(buf, "Yes")) {
197			val = 1;
198			errno = 0;
199			} else if (!strcmp(buf, "No"))
200			errno = 0;
201			else
202			errno = EINVAL;
203
204			if (errstrp != NULL) {
205			if (errno == 0)
206			*errstrp = NULL;
207			else
208			*errstrp = "invalid";
209			}
210			return val;
211			}
212
213
214			/*
215			* Internal functions to send/recv pdus.
216			*/
217
218			void
219			pdu_free_queue(struct pduq *channel)
220			{
221			struct pdu *p;
222
223			while ((p = TAILQ_FIRST(channel))) {
224			TAILQ_REMOVE(channel, p, entry);
225			pdu_free(p);
226			}
227			}
228
229			ssize_t
230			pdu_read(struct connection *c)
231			{
232			struct iovec iov[2];
233			unsigned int niov = 1;
234			ssize_t n;
235
236			bzero(&iov, sizeof(iov));
237			iov[0].iov_base = c->prbuf.buf + c->prbuf.wpos;
238			if (c->prbuf.wpos < c->prbuf.rpos)
239			iov[0].iov_len = c->prbuf.rpos - c->prbuf.wpos;
240			else {
241			iov[0].iov_len = c->prbuf.size - c->prbuf.wpos;
242			if (c->prbuf.rpos > 0) {
243			niov++;
244			iov[1].iov_base = c->prbuf.buf;
245			iov[1].iov_len = c->prbuf.rpos - 1;
246			}
247			}
248
249			if ((n = readv(c->fd, iov, niov)) == -1)
250			return -1;
251			if (n == 0)
252			/* XXX what should we do on close with remaining data? */
253			return 0;
254
255			c->prbuf.wpos += n;
256			if (c->prbuf.wpos >= c->prbuf.size)
257			c->prbuf.wpos -= c->prbuf.size;
258
259			return n;
260			}
261
262			ssize_t
263			pdu_write(struct connection *c)
264			{
265			struct iovec iov[PDU_WRIOV];
266			struct pdu b, nb;
267			unsigned int niov = 0, j;
268			size_t off, resid, size;
269			ssize_t n;
270
271			TAILQ_FOREACH(b, &c->pdu_w, entry) {
272			if (niov >= PDU_WRIOV)
273			break;
274			off = b->resid;
275			for (j = 0; j < PDU_MAXIOV && niov < PDU_WRIOV; j++) {
276			if (!b->iov[j].iov_len)
277			continue;
278			if (off >= b->iov[j].iov_len) {
279			off -= b->iov[j].iov_len;
280			continue;
281			}
282			iov[niov].iov_base = (char *)b->iov[j].iov_base + off;
283			iov[niov++].iov_len = b->iov[j].iov_len - off;
284			off = 0;
285			}
286			}
287
288			if ((n = writev(c->fd, iov, niov)) == -1) {
289			if (errno == EAGAIN \|\| errno == ENOBUFS \|\|
290			errno == EINTR) /* try later */
291			return 0;
292			else {
293			log_warn("pdu_write");
294			return -1;
295			}
296			}
297			if (n == 0)
298			return 0;
299
300			size = n;
301			for (b = TAILQ_FIRST(&c->pdu_w); b != NULL && size > 0; b = nb) {
302			nb = TAILQ_NEXT(b, entry);
303			resid = b->resid;
304			for (j = 0; j < PDU_MAXIOV; j++) {
305			if (resid >= b->iov[j].iov_len)
306			resid -= b->iov[j].iov_len;
307			else if (size >= b->iov[j].iov_len - resid) {
308			size -= b->iov[j].iov_len - resid;
309			b->resid += b->iov[j].iov_len - resid;
310			resid = 0;
311			} else {
312			b->resid += size;
313			size = 0;
314			break;
315			}
316			}
317			if (j == PDU_MAXIOV) {
318			/* all written */
319			TAILQ_REMOVE(&c->pdu_w, b, entry);
320			pdu_free(b);
321			}
322			}
323			return n;
324			}
325
326			int
327			pdu_pending(struct connection *c)
328			{
329			if (TAILQ_EMPTY(&c->pdu_w))
330			return 0;
331			else
332			return 1;
333			}
334
335			void
336			pdu_parse(struct connection *c)
337			{
338			struct pdu *p;
339			struct iscsi_pdu *ipdu;
340			char ahb, db;
341			size_t ahslen, dlen, off;
342			ssize_t n;
343			unsigned int j;
344
345			/* XXX XXX I DON'T LIKE YOU. CAN I REWRITE YOU? */
346
347			do {
348			if (!(p = c->prbuf.wip)) {
349			/* get and parse base header */
350			if (pdu_readbuf_len(&c->prbuf) < sizeof(*ipdu))
351			return;
352			if (!(p = pdu_new()))
353			goto fail;
354			if (!(ipdu = pdu_gethdr(p)))
355			goto fail;
356
357			c->prbuf.wip = p;
358			/*
359			* XXX maybe a pdu_readbuf_peek() would allow a better
360			* error handling.
361			*/
362			pdu_readbuf_read(&c->prbuf, ipdu, sizeof(*ipdu));
363
364			ahslen = ipdu->ahslen * sizeof(u_int32_t);
365			if (ahslen != 0) {
366			if (!(ahb = pdu_alloc(ahslen)) \|\|
367			pdu_addbuf(p, ahb, ahslen, PDU_AHS))
368			goto fail;
369			}
370
371			dlen = ipdu->datalen[0] << 16 \| ipdu->datalen[1] << 8 \|
372			ipdu->datalen[2];
373			if (dlen != 0) {
374			if (!(db = pdu_alloc(dlen)) \|\|
375			pdu_addbuf(p, db, dlen, PDU_DATA))
376			goto fail;
377			}
378
379			p->resid = sizeof(*ipdu);
380			} else {
381			off = p->resid;
382			for (j = 0; j < PDU_MAXIOV; j++) {
383			if (off >= p->iov[j].iov_len)
384			off -= p->iov[j].iov_len;
385			else {
386			n = pdu_readbuf_read(&c->prbuf,
387			(char *)p->iov[j].iov_base + off,
388			p->iov[j].iov_len - off);
389			p->resid += n;
390			if (n == 0 \|\| off + n !=
391			p->iov[j].iov_len)
392			return;
393			}
394			}
395			p->resid = 0; /* reset resid so pdu can be reused */
396			c->prbuf.wip = NULL;
397			task_pdu_cb(c, p);
398			}
399			} while (1);
400			fail:
401			fatalx("pdu_parse hit a space oddity");
402			}
403
404			size_t
405			pdu_readbuf_read(struct pdu_readbuf rb, void ptr, size_t len)
406			{
407			size_t l;
408
409			if (rb->rpos == rb->wpos) {
410			return 0;
411			} else if (rb->rpos < rb->wpos) {
412			l = PDU_MIN(rb->wpos - rb->rpos, len);
413			memcpy(ptr, rb->buf + rb->rpos, l);
414			rb->rpos += l;
415			return l;
416			} else {
417			l = PDU_MIN(rb->size - rb->rpos, len);
418			memcpy(ptr, rb->buf + rb->rpos, l);
419			rb->rpos += l;
420			if (rb->rpos == rb->size)
421			rb->rpos = 0;
422			if (l < len)
423			return l + pdu_readbuf_read(rb, (char *)ptr + l,
424			len - l);
425			return l;
426			}
427			}
428
429			size_t
430			pdu_readbuf_len(struct pdu_readbuf *rb)
431			{
432			if (rb->rpos <= rb->wpos)
433			return rb->wpos - rb->rpos;
434			else
435			return rb->size - (rb->rpos - rb->wpos);
436			}
437
438			int
439			pdu_readbuf_set(struct pdu_readbuf *rb, size_t bsize)
440			{
441			char *nb;
442
443			if (bsize < rb->size)
444			/* can't shrink */
445			return 0;
446			if ((nb = realloc(rb->buf, bsize)) == NULL) {
447			free(rb->buf);
448			return -1;
449			}
450			rb->buf = nb;
451			rb->size = bsize;
452			return 0;
453			}
454
455			void
456			pdu_readbuf_free(struct pdu_readbuf *rb)
457			{
458			free(rb->buf);
459			}