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#include "etherboot.h"
#include "init.h"
#include "proto.h"
#include <gpxe/in.h>
#include "nic.h"
/* NOTE: the NFS code is heavily inspired by the NetBSD netboot code (read:
* large portions are copied verbatim) as distributed in OSKit 0.97. A few
* changes were necessary to adapt the code to Etherboot and to fix several
* inconsistencies. Also the RPC message preparation is done "by hand" to
* avoid adding netsprintf() which I find hard to understand and use. */
/* NOTE 2: Etherboot does not care about things beyond the kernel image, so
* it loads the kernel image off the boot server (ARP_SERVER) and does not
* access the client root disk (root-path in dhcpd.conf), which would use
* ARP_ROOTSERVER. The root disk is something the operating system we are
* about to load needs to use. This is different from the OSKit 0.97 logic. */
/* NOTE 3: Symlink handling introduced by Anselm M Hoffmeister, 2003-July-14
* If a symlink is encountered, it is followed as far as possible (recursion
* possible, maximum 16 steps). There is no clearing of ".."'s inside the
* path, so please DON'T DO THAT. thx. */
#define START_OPORT 700 /* mountd usually insists on secure ports */
#define OPORT_SWEEP 200 /* make sure we don't leave secure range */
static int oport = START_OPORT;
static struct sockaddr_in mount_server;
static struct sockaddr_in nfs_server;
static unsigned long rpc_id;
/**************************************************************************
RPC_INIT - set up the ID counter to something fairly random
**************************************************************************/
static void rpc_init(void)
{
unsigned long t;
t = currticks();
rpc_id = t ^ (t << 8) ^ (t << 16);
}
/**************************************************************************
RPC_PRINTERROR - Print a low level RPC error message
**************************************************************************/
static void rpc_printerror(struct rpc_t *rpc)
{
if (rpc->u.reply.rstatus || rpc->u.reply.verifier ||
rpc->u.reply.astatus) {
/* rpc_printerror() is called for any RPC related error,
* suppress output if no low level RPC error happened. */
DBG("RPC error: (%d,%d,%d)\n", ntohl(rpc->u.reply.rstatus),
ntohl(rpc->u.reply.verifier),
ntohl(rpc->u.reply.astatus));
}
}
/**************************************************************************
AWAIT_RPC - Wait for an rpc packet
**************************************************************************/
static int await_rpc(int ival, void *ptr,
unsigned short ptype __unused, struct iphdr *ip,
struct udphdr *udp, struct tcphdr *tcp __unused)
{
struct rpc_t *rpc;
if (!udp)
return 0;
if (arptable[ARP_CLIENT].ipaddr.s_addr != ip->dest.s_addr)
return 0;
if (ntohs(udp->dest) != ival)
return 0;
if (nic.packetlen < ETH_HLEN + sizeof(struct iphdr) + sizeof(struct udphdr) + 8)
return 0;
rpc = (struct rpc_t *)&nic.packet[ETH_HLEN];
if (*(unsigned long *)ptr != ntohl(rpc->u.reply.id))
return 0;
if (MSG_REPLY != ntohl(rpc->u.reply.type))
return 0;
return 1;
}
/**************************************************************************
RPC_LOOKUP - Lookup RPC Port numbers
**************************************************************************/
static int rpc_lookup(struct sockaddr_in *addr, int prog, int ver, int sport)
{
struct rpc_t buf, *rpc;
unsigned long id;
int retries;
long *p;
id = rpc_id++;
buf.u.call.id = htonl(id);
buf.u.call.type = htonl(MSG_CALL);
buf.u.call.rpcvers = htonl(2); /* use RPC version 2 */
buf.u.call.prog = htonl(PROG_PORTMAP);
buf.u.call.vers = htonl(2); /* portmapper is version 2 */
buf.u.call.proc = htonl(PORTMAP_GETPORT);
p = (long *)buf.u.call.data;
*p++ = 0; *p++ = 0; /* auth credential */
*p++ = 0; *p++ = 0; /* auth verifier */
*p++ = htonl(prog);
*p++ = htonl(ver);
*p++ = htonl(IP_UDP);
*p++ = 0;
for (retries = 0; retries < MAX_RPC_RETRIES; retries++) {
long timeout;
udp_transmit(addr->sin_addr.s_addr, sport, addr->sin_port,
(char *)p - (char *)&buf, &buf);
timeout = rfc2131_sleep_interval(TIMEOUT, retries);
if (await_reply(await_rpc, sport, &id, timeout)) {
rpc = (struct rpc_t *)&nic.packet[ETH_HLEN];
if (rpc->u.reply.rstatus || rpc->u.reply.verifier ||
rpc->u.reply.astatus) {
rpc_printerror(rpc);
return 0;
} else {
return ntohl(rpc->u.reply.data[0]);
}
}
}
return 0;
}
/**************************************************************************
RPC_ADD_CREDENTIALS - Add RPC authentication/verifier entries
**************************************************************************/
static long *rpc_add_credentials(long *p)
{
int hl;
/* Here's the executive summary on authentication requirements of the
* various NFS server implementations: Linux accepts both AUTH_NONE
* and AUTH_UNIX authentication (also accepts an empty hostname field
* in the AUTH_UNIX scheme). *BSD refuses AUTH_NONE, but accepts
* AUTH_UNIX (also accepts an empty hostname field in the AUTH_UNIX
* scheme). To be safe, use AUTH_UNIX and pass the hostname if we have
* it (if the BOOTP/DHCP reply didn't give one, just use an empty
* hostname). */
hl = (hostnamelen + 3) & ~3;
/* Provide an AUTH_UNIX credential. */
*p++ = htonl(1); /* AUTH_UNIX */
*p++ = htonl(hl+20); /* auth length */
*p++ = htonl(0); /* stamp */
*p++ = htonl(hostnamelen); /* hostname string */
if (hostnamelen & 3) {
*(p + hostnamelen / 4) = 0; /* add zero padding */
}
memcpy(p, hostname, hostnamelen);
p += hl / 4;
*p++ = 0; /* uid */
*p++ = 0; /* gid */
*p++ = 0; /* auxiliary gid list */
/* Provide an AUTH_NONE verifier. */
*p++ = 0; /* AUTH_NONE */
*p++ = 0; /* auth length */
return p;
}
/**************************************************************************
NFS_PRINTERROR - Print a NFS error message
**************************************************************************/
static void nfs_printerror(int err)
{
switch (-err) {
case NFSERR_PERM:
printf("Not owner\n");
break;
case NFSERR_NOENT:
printf("No such file or directory\n");
break;
case NFSERR_ACCES:
printf("Permission denied\n");
break;
case NFSERR_ISDIR:
printf("Directory given where filename expected\n");
break;
case NFSERR_INVAL:
printf("Invalid filehandle\n");
break; // INVAL is not defined in NFSv2, some NFS-servers
// seem to use it in answers to v2 nevertheless.
case 9998:
printf("low-level RPC failure (parameter decoding problem?)\n");
break;
case 9999:
printf("low-level RPC failure (authentication problem?)\n");
break;
default:
printf("Unknown NFS error %d\n", -err);
}
}
/**************************************************************************
NFS_MOUNT - Mount an NFS Filesystem
**************************************************************************/
static int nfs_mount(struct sockaddr_in *server, char *path, char *fh, int sport)
{
struct rpc_t buf, *rpc;
unsigned long id;
int retries;
long *p;
int pathlen = strlen(path);
id = rpc_id++;
buf.u.call.id = htonl(id);
buf.u.call.type = htonl(MSG_CALL);
buf.u.call.rpcvers = htonl(2); /* use RPC version 2 */
buf.u.call.prog = htonl(PROG_MOUNT);
buf.u.call.vers = htonl(1); /* mountd is version 1 */
buf.u.call.proc = htonl(MOUNT_ADDENTRY);
p = rpc_add_credentials((long *)buf.u.call.data);
*p++ = htonl(pathlen);
if (pathlen & 3) {
*(p + pathlen / 4) = 0; /* add zero padding */
}
memcpy(p, path, pathlen);
p += (pathlen + 3) / 4;
for (retries = 0; retries < MAX_RPC_RETRIES; retries++) {
long timeout;
udp_transmit(server->sin_addr.s_addr, sport, server->sin_port,
(char *)p - (char *)&buf, &buf);
timeout = rfc2131_sleep_interval(TIMEOUT, retries);
if (await_reply(await_rpc, sport, &id, timeout)) {
rpc = (struct rpc_t *)&nic.packet[ETH_HLEN];
if (rpc->u.reply.rstatus || rpc->u.reply.verifier ||
rpc->u.reply.astatus || rpc->u.reply.data[0]) {
rpc_printerror(rpc);
if (rpc->u.reply.rstatus) {
/* RPC failed, no verifier, data[0] */
return -9999;
}
if (rpc->u.reply.astatus) {
/* RPC couldn't decode parameters */
return -9998;
}
return -ntohl(rpc->u.reply.data[0]);
} else {
memcpy(fh, rpc->u.reply.data + 1, NFS_FHSIZE);
return 0;
}
}
}
return -1;
}
/**************************************************************************
NFS_UMOUNTALL - Unmount all our NFS Filesystems on the Server
**************************************************************************/
static void nfs_umountall(struct sockaddr_in *server)
{
struct rpc_t buf, *rpc;
unsigned long id;
int retries;
long *p;
id = rpc_id++;
buf.u.call.id = htonl(id);
buf.u.call.type = htonl(MSG_CALL);
buf.u.call.rpcvers = htonl(2); /* use RPC version 2 */
buf.u.call.prog = htonl(PROG_MOUNT);
buf.u.call.vers = htonl(1); /* mountd is version 1 */
buf.u.call.proc = htonl(MOUNT_UMOUNTALL);
p = rpc_add_credentials((long *)buf.u.call.data);
for (retries = 0; retries < MAX_RPC_RETRIES; retries++) {
long timeout = rfc2131_sleep_interval(TIMEOUT, retries);
udp_transmit(server->sin_addr.s_addr, oport, server->sin_port,
(char *)p - (char *)&buf, &buf);
if (await_reply(await_rpc, oport, &id, timeout)) {
rpc = (struct rpc_t *)&nic.packet[ETH_HLEN];
if (rpc->u.reply.rstatus || rpc->u.reply.verifier ||
rpc->u.reply.astatus) {
rpc_printerror(rpc);
}
break;
}
}
}
/**************************************************************************
NFS_RESET - Reset the NFS subsystem
**************************************************************************/
static void nfs_reset ( void ) {
/* If we have a mount server, call nfs_umountall() */
if ( mount_server.sin_addr.s_addr ) {
nfs_umountall ( &mount_server );
}
/* Zero the data structures */
memset ( &mount_server, 0, sizeof ( mount_server ) );
memset ( &nfs_server, 0, sizeof ( nfs_server ) );
}
/***************************************************************************
* NFS_READLINK (AH 2003-07-14)
* This procedure is called when read of the first block fails -
* this probably happens when it's a directory or a symlink
* In case of successful readlink(), the dirname is manipulated,
* so that inside the nfs() function a recursion can be done.
**************************************************************************/
static int nfs_readlink(struct sockaddr_in *server, char *fh __unused,
char *path, char *nfh, int sport)
{
struct rpc_t buf, *rpc;
unsigned long id;
long *p;
int retries;
int pathlen = strlen(path);
id = rpc_id++;
buf.u.call.id = htonl(id);
buf.u.call.type = htonl(MSG_CALL);
buf.u.call.rpcvers = htonl(2); /* use RPC version 2 */
buf.u.call.prog = htonl(PROG_NFS);
buf.u.call.vers = htonl(2); /* nfsd is version 2 */
buf.u.call.proc = htonl(NFS_READLINK);
p = rpc_add_credentials((long *)buf.u.call.data);
memcpy(p, nfh, NFS_FHSIZE);
p += (NFS_FHSIZE / 4);
for (retries = 0; retries < MAX_RPC_RETRIES; retries++) {
long timeout = rfc2131_sleep_interval(TIMEOUT, retries);
udp_transmit(server->sin_addr.s_addr, sport, server->sin_port,
(char *)p - (char *)&buf, &buf);
if (await_reply(await_rpc, sport, &id, timeout)) {
rpc = (struct rpc_t *)&nic.packet[ETH_HLEN];
if (rpc->u.reply.rstatus || rpc->u.reply.verifier ||
rpc->u.reply.astatus || rpc->u.reply.data[0]) {
rpc_printerror(rpc);
if (rpc->u.reply.rstatus) {
/* RPC failed, no verifier, data[0] */
return -9999;
}
if (rpc->u.reply.astatus) {
/* RPC couldn't decode parameters */
return -9998;
}
return -ntohl(rpc->u.reply.data[0]);
} else {
// It *is* a link.
// If it's a relative link, append everything to dirname, filename TOO!
retries = strlen ( (char *)(&(rpc->u.reply.data[2]) ));
if ( *((char *)(&(rpc->u.reply.data[2]))) != '/' ) {
path[pathlen++] = '/';
while ( ( retries + pathlen ) > 298 ) {
retries--;
}
if ( retries > 0 ) {
memcpy(path + pathlen, &(rpc->u.reply.data[2]), retries + 1);
} else { retries = 0; }
path[pathlen + retries] = 0;
} else {
// Else make it the only path.
if ( retries > 298 ) { retries = 298; }
memcpy ( path, &(rpc->u.reply.data[2]), retries + 1 );
path[retries] = 0;
}
return 0;
}
}
}
return -1;
}
/**************************************************************************
NFS_LOOKUP - Lookup Pathname
**************************************************************************/
static int nfs_lookup(struct sockaddr_in *server, char *fh, char *path, char *nfh,
int sport)
{
struct rpc_t buf, *rpc;
unsigned long id;
long *p;
int retries;
int pathlen = strlen(path);
id = rpc_id++;
buf.u.call.id = htonl(id);
buf.u.call.type = htonl(MSG_CALL);
buf.u.call.rpcvers = htonl(2); /* use RPC version 2 */
buf.u.call.prog = htonl(PROG_NFS);
buf.u.call.vers = htonl(2); /* nfsd is version 2 */
buf.u.call.proc = htonl(NFS_LOOKUP);
p = rpc_add_credentials((long *)buf.u.call.data);
memcpy(p, fh, NFS_FHSIZE);
p += (NFS_FHSIZE / 4);
*p++ = htonl(pathlen);
if (pathlen & 3) {
*(p + pathlen / 4) = 0; /* add zero padding */
}
memcpy(p, path, pathlen);
p += (pathlen + 3) / 4;
for (retries = 0; retries < MAX_RPC_RETRIES; retries++) {
long timeout = rfc2131_sleep_interval(TIMEOUT, retries);
udp_transmit(server->sin_addr.s_addr, sport, server->sin_port,
(char *)p - (char *)&buf, &buf);
if (await_reply(await_rpc, sport, &id, timeout)) {
rpc = (struct rpc_t *)&nic.packet[ETH_HLEN];
if (rpc->u.reply.rstatus || rpc->u.reply.verifier ||
rpc->u.reply.astatus || rpc->u.reply.data[0]) {
rpc_printerror(rpc);
if (rpc->u.reply.rstatus) {
/* RPC failed, no verifier, data[0] */
return -9999;
}
if (rpc->u.reply.astatus) {
/* RPC couldn't decode parameters */
return -9998;
}
return -ntohl(rpc->u.reply.data[0]);
} else {
memcpy(nfh, rpc->u.reply.data + 1, NFS_FHSIZE);
return 0;
}
}
}
return -1;
}
/**************************************************************************
NFS_READ - Read File on NFS Server
**************************************************************************/
static int nfs_read(struct sockaddr_in *server, char *fh, int offset, int len,
int sport)
{
struct rpc_t buf, *rpc;
unsigned long id;
int retries;
long *p;
static int tokens=0;
/*
* Try to implement something similar to a window protocol in
* terms of response to losses. On successful receive, increment
* the number of tokens by 1 (cap at 256). On failure, halve it.
* When the number of tokens is >= 2, use a very short timeout.
*/
id = rpc_id++;
buf.u.call.id = htonl(id);
buf.u.call.type = htonl(MSG_CALL);
buf.u.call.rpcvers = htonl(2); /* use RPC version 2 */
buf.u.call.prog = htonl(PROG_NFS);
buf.u.call.vers = htonl(2); /* nfsd is version 2 */
buf.u.call.proc = htonl(NFS_READ);
p = rpc_add_credentials((long *)buf.u.call.data);
memcpy(p, fh, NFS_FHSIZE);
p += NFS_FHSIZE / 4;
*p++ = htonl(offset);
*p++ = htonl(len);
*p++ = 0; /* unused parameter */
for (retries = 0; retries < MAX_RPC_RETRIES; retries++) {
long timeout = rfc2131_sleep_interval(TIMEOUT, retries);
if (tokens >= 2)
timeout = TICKS_PER_SEC/2;
udp_transmit(server->sin_addr.s_addr, sport, server->sin_port,
(char *)p - (char *)&buf, &buf);
if (await_reply(await_rpc, sport, &id, timeout)) {
if (tokens < 256)
tokens++;
rpc = (struct rpc_t *)&nic.packet[ETH_HLEN];
if (rpc->u.reply.rstatus || rpc->u.reply.verifier ||
rpc->u.reply.astatus || rpc->u.reply.data[0]) {
rpc_printerror(rpc);
if (rpc->u.reply.rstatus) {
/* RPC failed, no verifier, data[0] */
return -9999;
}
if (rpc->u.reply.astatus) {
/* RPC couldn't decode parameters */
return -9998;
}
return -ntohl(rpc->u.reply.data[0]);
} else {
return 0;
}
} else
tokens >>= 1;
}
return -1;
}
/**************************************************************************
NFS - Download extended BOOTP data, or kernel image from NFS server
**************************************************************************/
static int nfs ( char *url __unused, struct sockaddr_in *server,
char *name, struct buffer *buffer ) {
static int recursion = 0;
int sport;
int err, namelen = strlen(name);
char dirname[300], *fname;
char dirfh[NFS_FHSIZE]; /* file handle of directory */
char filefh[NFS_FHSIZE]; /* file handle of kernel image */
int rlen, size, offs, len;
struct rpc_t *rpc;
sport = oport++;
if (oport > START_OPORT+OPORT_SWEEP) {
oport = START_OPORT;
}
mount_server.sin_addr = nfs_server.sin_addr = server->sin_addr;
mount_server.sin_port = rpc_lookup(server, PROG_MOUNT, 1, sport);
if ( ! mount_server.sin_port ) {
DBG ( "Cannot get mount port from %!:%d\n",
server->sin_addr.s_addr, server->sin_port );
return 0;
}
nfs_server.sin_port = rpc_lookup(server, PROG_NFS, 2, sport);
if ( ! mount_server.sin_port ) {
DBG ( "Cannot get nfs port from %!:%d\n",
server->sin_addr.s_addr, server->sin_port );
return 0;
}
if ( name != dirname ) {
memcpy(dirname, name, namelen + 1);
}
recursion = 0;
nfssymlink:
if ( recursion > NFS_MAXLINKDEPTH ) {
DBG ( "\nRecursion: More than %d symlinks followed. Abort.\n",
NFS_MAXLINKDEPTH );
return 0;
}
recursion++;
fname = dirname + (namelen - 1);
while (fname >= dirname) {
if (*fname == '/') {
*fname = '\0';
fname++;
break;
}
fname--;
}
if (fname < dirname) {
DBG("can't parse file name %s\n", name);
return 0;
}
err = nfs_mount(&mount_server, dirname, dirfh, sport);
if (err) {
DBG("mounting %s: ", dirname);
nfs_printerror(err);
/* just to be sure... */
nfs_reset();
return 0;
}
err = nfs_lookup(&nfs_server, dirfh, fname, filefh, sport);
if (err) {
DBG("looking up %s: ", fname);
nfs_printerror(err);
nfs_reset();
return 0;
}
offs = 0;
size = -1; /* will be set properly with the first reply */
len = NFS_READ_SIZE; /* first request is always full size */
do {
err = nfs_read(&nfs_server, filefh, offs, len, sport);
if ((err <= -NFSERR_ISDIR)&&(err >= -NFSERR_INVAL) && (offs == 0)) {
// An error occured. NFS servers tend to sending
// errors 21 / 22 when symlink instead of real file
// is requested. So check if it's a symlink!
if ( nfs_readlink(&nfs_server, dirfh, dirname,
filefh, sport) == 0 ) {
printf("\nLoading symlink:%s ..",dirname);
goto nfssymlink;
}
nfs_printerror(err);
nfs_reset();
return 0;
}
if (err) {
printf("\nError reading at offset %d: ", offs);
nfs_printerror(err);
nfs_reset();
return 0;
}
rpc = (struct rpc_t *)&nic.packet[ETH_HLEN];
/* size must be found out early to allow EOF detection */
if (size == -1) {
size = ntohl(rpc->u.reply.data[6]);
}
rlen = ntohl(rpc->u.reply.data[18]);
if (rlen > len) {
rlen = len; /* shouldn't happen... */
}
if ( ! fill_buffer ( buffer, &rpc->u.reply.data[19],
offs, rlen ) ) {
nfs_reset();
return 0;
}
offs += rlen;
/* last request is done with matching requested read size */
if (size-offs < NFS_READ_SIZE) {
len = size-offs;
}
} while (len != 0);
/* len == 0 means that all the file has been read */
return 1;
}
INIT_FN ( INIT_RPC, rpc_init, nfs_reset, nfs_reset );
struct protocol nfs_protocol __protocol = {
.name = "nfs",
.default_port = SUNRPC_PORT,
.load = nfs,
};