1 #include "all.h"
2
3 enum {
4 ARgiveup = 100,
5 };
6
7 static uchar*
gstring(uchar * p,uchar * ep,char ** s)8 gstring(uchar *p, uchar *ep, char **s)
9 {
10 uint n;
11
12 if(p == nil)
13 return nil;
14 if(p+BIT16SZ > ep)
15 return nil;
16 n = GBIT16(p);
17 p += BIT16SZ;
18 if(p+n > ep)
19 return nil;
20 *s = malloc(n+1);
21 memmove((*s), p, n);
22 (*s)[n] = '\0';
23 p += n;
24 return p;
25 }
26
27 static uchar*
gcarray(uchar * p,uchar * ep,uchar ** s,int * np)28 gcarray(uchar *p, uchar *ep, uchar **s, int *np)
29 {
30 uint n;
31
32 if(p == nil)
33 return nil;
34 if(p+BIT16SZ > ep)
35 return nil;
36 n = GBIT16(p);
37 p += BIT16SZ;
38 if(p+n > ep)
39 return nil;
40 *s = malloc(n);
41 if(*s == nil)
42 return nil;
43 memmove((*s), p, n);
44 *np = n;
45 p += n;
46 return p;
47 }
48
49 static uchar*
convM2AI(uchar * p,int n,AuthInfo ** aip)50 convM2AI(uchar *p, int n, AuthInfo **aip)
51 {
52 uchar *e = p+n;
53 AuthInfo *ai;
54
55 ai = mallocz(sizeof(*ai), 1);
56 if(ai == nil)
57 return nil;
58
59 p = gstring(p, e, &ai->cuid);
60 p = gstring(p, e, &ai->suid);
61 p = gstring(p, e, &ai->cap);
62 p = gcarray(p, e, &ai->secret, &ai->nsecret);
63 if(p == nil)
64 auth_freeAI(ai);
65 else
66 *aip = ai;
67 return p;
68 }
69
70 static int
dorpc(AuthRpc * rpc,char * verb,char * val,int len,AuthGetkey * getkey)71 dorpc(AuthRpc *rpc, char *verb, char *val, int len, AuthGetkey *getkey)
72 {
73 int ret;
74
75 for(;;){
76 if((ret = auth_rpc(rpc, verb, val, len)) != ARneedkey && ret != ARbadkey)
77 return ret;
78 if(getkey == nil)
79 return ARgiveup; /* don't know how */
80 if((*getkey)(rpc->arg) < 0)
81 return ARgiveup; /* user punted */
82 }
83 }
84
85 static int
doread(Session * s,Fid * f,void * buf,int n)86 doread(Session *s, Fid *f, void *buf, int n)
87 {
88 s->f.fid = f - s->fids;
89 s->f.offset = 0;
90 s->f.count = n;
91 if(xmesg(s, Tread) < 0)
92 return -1;
93 n = s->f.count;
94 memmove(buf, s->f.data, n);
95 return n;
96 }
97
98 static int
dowrite(Session * s,Fid * f,void * buf,int n)99 dowrite(Session *s, Fid *f, void *buf, int n)
100 {
101 s->f.fid = f - s->fids;
102 s->f.offset = 0;
103 s->f.count = n;
104 s->f.data = (char *)buf;
105 if(xmesg(s, Twrite) < 0)
106 return -1;
107 return n;
108 }
109
110 /*
111 * this just proxies what the factotum tells it to.
112 */
113 AuthInfo*
authproto(Session * s,Fid * f,AuthRpc * rpc,AuthGetkey * getkey,char * params)114 authproto(Session *s, Fid *f, AuthRpc *rpc, AuthGetkey *getkey, char *params)
115 {
116 char *buf;
117 int m, n, ret;
118 AuthInfo *a;
119 char oerr[ERRMAX];
120
121 rerrstr(oerr, sizeof oerr);
122 werrstr("UNKNOWN AUTH ERROR");
123
124 if(dorpc(rpc, "start", params, strlen(params), getkey) != ARok){
125 werrstr("fauth_proxy start: %r");
126 return nil;
127 }
128
129 buf = malloc(AuthRpcMax);
130 if(buf == nil)
131 return nil;
132 for(;;){
133 switch(dorpc(rpc, "read", nil, 0, getkey)){
134 case ARdone:
135 free(buf);
136 a = auth_getinfo(rpc);
137 errstr(oerr, sizeof oerr); /* no error, restore whatever was there */
138 return a;
139 case ARok:
140 if(dowrite(s, f, rpc->arg, rpc->narg) != rpc->narg){
141 werrstr("auth_proxy write fd: %r");
142 goto Error;
143 }
144 break;
145 case ARphase:
146 n = 0;
147 memset(buf, 0, AuthRpcMax);
148 while((ret = dorpc(rpc, "write", buf, n, getkey)) == ARtoosmall){
149 if(atoi(rpc->arg) > AuthRpcMax)
150 break;
151 m = doread(s, f, buf+n, atoi(rpc->arg)-n);
152 if(m <= 0){
153 if(m == 0)
154 werrstr("auth_proxy short read: %s", buf);
155 goto Error;
156 }
157 n += m;
158 }
159 if(ret != ARok){
160 werrstr("auth_proxy rpc write: %s: %r", buf);
161 goto Error;
162 }
163 break;
164 default:
165 werrstr("auth_proxy rpc: %r");
166 goto Error;
167 }
168 }
169 Error:
170 free(buf);
171 return nil;
172 }
173
174 /* returns 0 if auth succeeded (or unneeded), -1 otherwise */
175 int
authhostowner(Session * s)176 authhostowner(Session *s)
177 {
178 Fid *af, *f;
179 int rv = -1;
180 int afd;
181 AuthInfo *ai;
182 AuthRpc *rpc;
183
184 /* get a fid to authenticate over */
185 f = nil;
186 af = newfid(s);
187 s->f.afid = af - s->fids;
188 s->f.uname = getuser();
189 s->f.aname = s->spec;
190 if(xmesg(s, Tauth)){
191 /* not needed */
192 rv = 0;
193 goto out;
194 }
195
196 quotefmtinstall(); /* just in case */
197
198 afd = open("/mnt/factotum/rpc", ORDWR);
199 if(afd < 0){
200 werrstr("opening /mnt/factotum/rpc: %r");
201 goto out;
202 }
203
204 rpc = auth_allocrpc(afd);
205 if(rpc == nil)
206 goto out;
207
208 ai = authproto(s, af, rpc, auth_getkey, "proto=p9any role=client");
209 if(ai != nil){
210 rv = 0;
211 auth_freeAI(ai);
212 }
213 auth_freerpc(rpc);
214 close(afd);
215
216 /* try attaching with the afid */
217 chat("attaching as hostowner...");
218 f = newfid(s);
219 s->f.fid = f - s->fids;
220 s->f.afid = af - s->fids;;
221 s->f.uname = getuser();
222 s->f.aname = s->spec;
223 if(xmesg(s, Tattach) == 0)
224 rv = 0;
225 out:
226 if(af != nil){
227 putfid(s, af);
228 s->f.fid = af - s->fids;
229 xmesg(s, Tclunk);
230 }
231 if(f != nil){
232 putfid(s, f);
233 s->f.fid = f - s->fids;
234 xmesg(s, Tclunk);
235 }
236
237 return rv;
238 }
239
240