9d7d20d99e9c1a4cc651d7256fcde109f759210a
[nfs-utils.git] / utils / mountd / cache.c
1
2 /*
3  * Handle communication with knfsd internal cache
4  *
5  * We open /proc/net/rpc/{auth.unix.ip,nfsd.export,nfsd.fh}/channel
6  * and listen for requests (using my_svc_run)
7  * 
8  */
9 #include "config.h"
10
11 #include <sys/types.h>
12 #include <sys/select.h>
13 #include <sys/stat.h>
14 #include <time.h>
15 #include <netinet/in.h>
16 #include <arpa/inet.h>
17 #include <unistd.h>
18 #include <fcntl.h>
19 #include <errno.h>
20 #include <ctype.h>
21 #include "misc.h"
22 #include "nfslib.h"
23 #include "exportfs.h"
24 #include "mountd.h"
25 #include "xmalloc.h"
26
27 /*
28  * Support routines for text-based upcalls.
29  * Fields are separated by spaces.
30  * Fields are either mangled to quote space tab newline slosh with slosh
31  * or a hexified with a leading \x
32  * Record is terminated with newline.
33  *
34  */
35 void cache_export_ent(char *domain, struct exportent *exp);
36
37
38 char *lbuf  = NULL;
39 int lbuflen = 0;
40
41 void auth_unix_ip(FILE *f)
42 {
43         /* requests are
44          *  class IP-ADDR
45          * Ignore if class != "nfsd"
46          * Otherwise find domainname and write back:
47          *
48          *  "nfsd" IP-ADDR expiry domainname
49          */
50         char *cp;
51         char class[20];
52         char ipaddr[20];
53         char *client;
54         struct in_addr addr;
55         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
56                 return;
57
58         cp = lbuf;
59
60         if (qword_get(&cp, class, 20) <= 0 ||
61             strcmp(class, "nfsd") != 0)
62                 return;
63
64         if (qword_get(&cp, ipaddr, 20) <= 0)
65                 return;
66
67         if (inet_aton(ipaddr, &addr)==0)
68                 return;
69
70         /* addr is a valid, interesting address, find the domain name... */
71         client = client_compose(addr);
72
73         
74         qword_print(f, "nfsd");
75         qword_print(f, ipaddr);
76         qword_printint(f, time(0)+30*60);
77         if (client)
78                 qword_print(f, *client?client:"DEFAULT");
79         qword_eol(f);
80
81         if (client) free(client);
82         
83 }
84
85 void nfsd_fh(FILE *f)
86 {
87         /* request are:
88          *  domain fsidtype fsid
89          * interpret fsid, find export point and options, and write:
90          *  domain fsidtype fsid expiry path
91          */
92         char *cp;
93         char *dom;
94         int fsidtype;
95         int fsidlen;
96         unsigned int dev, major=0, minor=0;
97         unsigned int inode=0;
98         unsigned int fsidnum=0;
99         char fsid[32];
100         struct exportent *found = NULL;
101         nfs_export *exp;
102         int i;
103         int dev_missing = 0;
104
105         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
106                 return;
107
108         cp = lbuf;
109
110         dom = malloc(strlen(cp));
111         if (dom == NULL)
112                 return;
113         if (qword_get(&cp, dom, strlen(cp)) <= 0)
114                 goto out;
115         if (qword_get_int(&cp, &fsidtype) != 0)
116                 goto out;
117         if (fsidtype < 0 || fsidtype > 1)
118                 goto out; /* unknown type */
119         if ((fsidlen = qword_get(&cp, fsid, 32)) <= 0)
120                 goto out;
121         switch(fsidtype) {
122         case 0: /* 4 bytes: 2 major, 2 minor, 4 inode */
123                 if (fsidlen != 8)
124                         goto out;
125                 memcpy(&dev, fsid, 4);
126                 memcpy(&inode, fsid+4, 4);
127                 major = ntohl(dev)>>16;
128                 minor = ntohl(dev) & 0xFFFF;
129                 break;
130
131         case 1: /* 4 bytes - fsid */
132                 if (fsidlen != 4)
133                         goto out;
134                 memcpy(&fsidnum, fsid, 4);
135                 break;
136         }
137
138         /* Now determine export point for this fsid/domain */
139         for (i=0 ; i < MCL_MAXTYPES; i++) {
140                 for (exp = exportlist[i]; exp; exp = exp->m_next) {
141                         if (!client_member(dom, exp->m_client->m_hostname))
142                                 continue;
143                         if (fsidtype == 1 &&
144                             ((exp->m_export.e_flags & NFSEXP_FSID) == 0 ||
145                              exp->m_export.e_fsid != fsidnum))
146                                 continue;
147                         if (fsidtype == 0) {
148                                 struct stat stb;
149                                 if (exp->m_export.e_mountpoint &&
150                                     !is_mountpoint(exp->m_export.e_mountpoint[0]?
151                                                    exp->m_export.e_mountpoint:
152                                                    exp->m_export.e_path))
153                                         dev_missing ++;
154                                 if (stat(exp->m_export.e_path, &stb) != 0)
155                                         continue;
156                                 if (stb.st_ino != inode)
157                                         continue;
158                                 if (major != major(stb.st_dev) ||
159                                     minor != minor(stb.st_dev))
160                                         continue;
161                         }
162                         /* It's a match !! */
163                         if (!found)
164                                 found = &exp->m_export;
165                         else if (strcmp(found->e_path, exp->m_export.e_path)!= 0)
166                         {
167                                 xlog(L_WARNING, "%s and %s have same filehandle for %s, using first",
168                                      found->e_path, exp->m_export.e_path, dom);
169                         }
170                 }
171         }
172         if (found && 
173             found->e_mountpoint &&
174             !is_mountpoint(found->e_mountpoint[0]?
175                            found->e_mountpoint:
176                            found->e_path)) {
177                 /* Cannot export this yet 
178                  * should log a warning, but need to rate limit
179                    xlog(L_WARNING, "%s not exported as %d not a mountpoint",
180                    found->e_path, found->e_mountpoint);
181                  */
182                 /* FIXME we need to make sure we re-visit this later */
183                 goto out;
184         }
185         if (!found && dev_missing) {
186                 /* The missing dev could be what we want, so just be
187                  * quite rather than returning stale yet
188                  */
189                 goto out;
190         }
191
192         cache_export_ent(dom, found);
193
194         qword_print(f, dom);
195         qword_printint(f, fsidtype);
196         qword_printhex(f, fsid, fsidlen);
197         qword_printint(f, time(0)+30*60);
198         if (found)
199                 qword_print(f, found->e_path);
200         qword_eol(f);
201  out:
202         free(dom);
203         return;         
204 }
205
206 void nfsd_export(FILE *f)
207 {
208         /* requests are:
209          *  domain path
210          * determine export options and return:
211          *  domain path expiry flags anonuid anongid fsid
212          */
213
214         char *cp;
215         int i;
216         char *dom, *path;
217         nfs_export *exp, *found = NULL;
218
219
220         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
221                 return;
222
223         cp = lbuf;
224         dom = malloc(strlen(cp));
225         path = malloc(strlen(cp));
226
227         if (!dom || !path)
228                 goto out;
229
230         if (qword_get(&cp, dom, strlen(lbuf)) <= 0)
231                 goto out;
232         if (qword_get(&cp, path, strlen(lbuf)) <= 0)
233                 goto out;
234
235         /* now find flags for this export point in this domain */
236         for (i=0 ; i < MCL_MAXTYPES; i++) {
237                 for (exp = exportlist[i]; exp; exp = exp->m_next) {
238                         if (!client_member(dom, exp->m_client->m_hostname))
239                                 continue;
240                         if (strcmp(path, exp->m_export.e_path))
241                                 continue;
242                         if (!found)
243                                 found = exp;
244                         else {
245                                 xlog(L_WARNING, "%s exported to both %s and %s in %s",
246                                      path, exp->m_client->m_hostname, found->m_client->m_hostname,
247                                      dom);
248                         }
249                 }
250         }
251
252         qword_print(f, dom);
253         qword_print(f, path);
254         qword_printint(f, time(0)+30*60);
255         if (found) {
256                 qword_printint(f, found->m_export.e_flags);
257                 qword_printint(f, found->m_export.e_anonuid);
258                 qword_printint(f, found->m_export.e_anongid);
259                 qword_printint(f, found->m_export.e_fsid);
260         }
261         qword_eol(f);
262  out:
263         if (dom) free(dom);
264         if (path) free(path);
265 }
266
267
268 struct {
269         char *cache_name;
270         void (*cache_handle)(FILE *f);
271         FILE *f;
272 } cachelist[] = {
273         { "auth.unix.ip", auth_unix_ip},
274         { "nfsd.export", nfsd_export},
275         { "nfsd.fh", nfsd_fh},
276         { NULL, NULL }
277 };
278
279 void cache_open(void) 
280 {
281         int i;
282         for (i=0; cachelist[i].cache_name; i++ ){
283                 char path[100];
284                 sprintf(path, "/proc/net/rpc/%s/channel", cachelist[i].cache_name);
285                 cachelist[i].f = fopen(path, "r+");
286         }
287 }
288
289 void cache_set_fds(fd_set *fdset)
290 {
291         int i;
292         for (i=0; cachelist[i].cache_name; i++) {
293                 if (cachelist[i].f)
294                         FD_SET(fileno(cachelist[i].f), fdset);
295         }
296 }
297
298 int cache_process_req(fd_set *readfds) 
299 {
300         int i;
301         int cnt = 0;
302         for (i=0; cachelist[i].cache_name; i++) {
303                 if (cachelist[i].f != NULL &&
304                     FD_ISSET(fileno(cachelist[i].f), readfds)) {
305                         cnt++;
306                         cachelist[i].cache_handle(cachelist[i].f);
307                 }
308         }
309         return cnt;
310 }
311
312
313 /*
314  * Give IP->domain and domain+path->options to kernel
315  * % echo nfsd $IP  $[now+30*60] $domain > /proc/net/rpc/auth.unix.ip/channel
316  * % echo $domain $path $[now+30*60] $options $anonuid $anongid $fsid > /proc/net/rpc/nfsd.export/channel
317  */
318
319 void cache_export_ent(char *domain, struct exportent *exp)
320 {
321
322         FILE *f = fopen("/proc/net/rpc/nfsd.export/channel", "r+");
323         if (!f)
324                 return;
325
326         qword_print(f, domain);
327         qword_print(f, exp->e_path);
328         qword_printint(f, time(0)+30*60);
329         qword_printint(f, exp->e_flags);
330         qword_printint(f, exp->e_anonuid);
331         qword_printint(f, exp->e_anongid);
332         qword_printint(f, exp->e_fsid);
333         qword_eol(f);
334
335         fclose(f);
336 }
337
338 void cache_export(nfs_export *exp)
339 {
340         FILE *f;
341
342         f = fopen("/proc/net/rpc/auth.unix.ip/channel", "r+");
343         if (!f)
344                 return;
345
346         qword_print(f, "nfsd");
347         qword_print(f, inet_ntoa(exp->m_client->m_addrlist[0]));
348         qword_printint(f, time(0)+30*60);
349         qword_print(f, exp->m_client->m_hostname);
350         qword_eol(f);
351         
352         fclose(f);
353
354         cache_export_ent(exp->m_client->m_hostname, &exp->m_export);
355 }
356
357 /* Get a filehandle.
358  * { 
359  *   echo $domain $path $length 
360  *   read filehandle <&0
361  * } <> /proc/fs/nfs/filehandle
362  */
363 struct nfs_fh_len *
364 cache_get_filehandle(nfs_export *exp, int len, char *p)
365 {
366         FILE *f = fopen("/proc/fs/nfs/filehandle", "r+");
367         char buf[200];
368         char *bp = buf;
369         static struct nfs_fh_len fh;
370         if (!f)
371                 return NULL;
372
373         qword_print(f, exp->m_client->m_hostname);
374         qword_print(f, p);
375         qword_printint(f, len); 
376         qword_eol(f);
377         
378         if (fgets(buf, sizeof(buf), f) == NULL)
379                 return NULL;
380         memset(fh.fh_handle, 0, sizeof(fh.fh_handle));
381         fh.fh_size = qword_get(&bp, fh.fh_handle, NFS3_FHSIZE);
382         return &fh;
383 }
384