1 0e43f5c6 2011-10-05 rsc #include <u.h>
  2 0e43f5c6 2011-10-05 rsc #include <libc.h>
  3 0e43f5c6 2011-10-05 rsc #include <mp.h>
  4 0e43f5c6 2011-10-05 rsc #include <libsec.h>
  5 0e43f5c6 2011-10-05 rsc #include <auth.h>
  6 0e43f5c6 2011-10-05 rsc #include <thread.h>
  7 0e43f5c6 2011-10-05 rsc #include <9pclient.h>
  8 0e43f5c6 2011-10-05 rsc #include <bio.h>
  9 0e43f5c6 2011-10-05 rsc 
 10 0e43f5c6 2011-10-05 rsc void
 11 0e43f5c6 2011-10-05 rsc usage(void)
 12 0e43f5c6 2011-10-05 rsc {
 13 0e43f5c6 2011-10-05 rsc 	fprint(2, "usage: 9 dsasign [-i id] [-v] key <data\n");
 14 0e43f5c6 2011-10-05 rsc 	threadexitsall("usage");
 15 0e43f5c6 2011-10-05 rsc }
 16 0e43f5c6 2011-10-05 rsc 
 17 0e43f5c6 2011-10-05 rsc static void doVerify(void);
 18 0e43f5c6 2011-10-05 rsc static char *getline(int*);
 19 0e43f5c6 2011-10-05 rsc 
 20 0e43f5c6 2011-10-05 rsc char *id;
 21 0e43f5c6 2011-10-05 rsc Biobuf b;
 22 0e43f5c6 2011-10-05 rsc int nid;
 23 0e43f5c6 2011-10-05 rsc char *key;
 24 0e43f5c6 2011-10-05 rsc 
 25 0e43f5c6 2011-10-05 rsc void
 26 0e43f5c6 2011-10-05 rsc threadmain(int argc, char **argv)
 27 0e43f5c6 2011-10-05 rsc {
 28 0e43f5c6 2011-10-05 rsc 	int n, verify;
 29 0e43f5c6 2011-10-05 rsc 	char *text, *p;
 30 0e43f5c6 2011-10-05 rsc 	uchar digest[SHA1dlen];
 31 0e43f5c6 2011-10-05 rsc 	AuthRpc *rpc;
 32 0e43f5c6 2011-10-05 rsc 	Fmt fmt;
 33 fa325e9b 2020-01-10 cross 
 34 0e43f5c6 2011-10-05 rsc 	fmtinstall('[', encodefmt);
 35 0e43f5c6 2011-10-05 rsc 	fmtinstall('H', encodefmt);
 36 fa325e9b 2020-01-10 cross 
 37 0e43f5c6 2011-10-05 rsc 	verify = 0;
 38 0e43f5c6 2011-10-05 rsc 	id = "";
 39 0e43f5c6 2011-10-05 rsc 	ARGBEGIN{
 40 0e43f5c6 2011-10-05 rsc 	case 'i':
 41 0e43f5c6 2011-10-05 rsc 		id = EARGF(usage());
 42 0e43f5c6 2011-10-05 rsc 		break;
 43 0e43f5c6 2011-10-05 rsc 	case 'v':
 44 0e43f5c6 2011-10-05 rsc 		verify = 1;
 45 0e43f5c6 2011-10-05 rsc 		break;
 46 0e43f5c6 2011-10-05 rsc 	default:
 47 0e43f5c6 2011-10-05 rsc 		usage();
 48 0e43f5c6 2011-10-05 rsc 	}ARGEND
 49 fa325e9b 2020-01-10 cross 
 50 0e43f5c6 2011-10-05 rsc 	if(argc != 1)
 51 0e43f5c6 2011-10-05 rsc 		usage();
 52 0e43f5c6 2011-10-05 rsc 	key = argv[0];
 53 0e43f5c6 2011-10-05 rsc 	nid = strlen(id);
 54 0e43f5c6 2011-10-05 rsc 
 55 0e43f5c6 2011-10-05 rsc 	Binit(&b, 0, OREAD);
 56 0e43f5c6 2011-10-05 rsc 	if(verify) {
 57 0e43f5c6 2011-10-05 rsc 		doVerify();
 58 0e43f5c6 2011-10-05 rsc 		threadexitsall(nil);
 59 0e43f5c6 2011-10-05 rsc 	}
 60 0e43f5c6 2011-10-05 rsc 
 61 0e43f5c6 2011-10-05 rsc 	if((rpc = auth_allocrpc()) == nil){
 62 0e43f5c6 2011-10-05 rsc 		fprint(2, "dsasign: auth_allocrpc: %r\n");
 63 0e43f5c6 2011-10-05 rsc 		threadexits("rpc");
 64 0e43f5c6 2011-10-05 rsc 	}
 65 0e43f5c6 2011-10-05 rsc 	key = smprint("proto=dsa role=sign %s", key);
 66 0e43f5c6 2011-10-05 rsc 	if(auth_rpc(rpc, "start", key, strlen(key)) != ARok){
 67 0e43f5c6 2011-10-05 rsc 		fprint(2, "dsasign: auth 'start' failed: %r\n");
 68 0e43f5c6 2011-10-05 rsc 		auth_freerpc(rpc);
 69 0e43f5c6 2011-10-05 rsc 		threadexits("rpc");
 70 0e43f5c6 2011-10-05 rsc 	}
 71 fa325e9b 2020-01-10 cross 
 72 0e43f5c6 2011-10-05 rsc 	print("+%s\n", id);
 73 0e43f5c6 2011-10-05 rsc 
 74 0e43f5c6 2011-10-05 rsc 	Binit(&b, 0, OREAD);
 75 0e43f5c6 2011-10-05 rsc 	fmtstrinit(&fmt);
 76 0e43f5c6 2011-10-05 rsc 	while((p = getline(&n)) != nil) {
 77 0e43f5c6 2011-10-05 rsc 		if(p[0] == '-' || p[0] == '+')
 78 0e43f5c6 2011-10-05 rsc 			print("+");
 79 0e43f5c6 2011-10-05 rsc 		print("%s\n", p);
 80 0e43f5c6 2011-10-05 rsc 		fmtprint(&fmt, "%s\n", p);
 81 0e43f5c6 2011-10-05 rsc 	}
 82 0e43f5c6 2011-10-05 rsc 	text = fmtstrflush(&fmt);
 83 0e43f5c6 2011-10-05 rsc 	sha1((uchar*)text, strlen(text), digest, nil);
 84 0e43f5c6 2011-10-05 rsc 
 85 0e43f5c6 2011-10-05 rsc 	if(auth_rpc(rpc, "write", digest, SHA1dlen) != ARok)
 86 0e43f5c6 2011-10-05 rsc 		sysfatal("auth write in sign failed: %r");
 87 0e43f5c6 2011-10-05 rsc 	if(auth_rpc(rpc, "read", nil, 0) != ARok)
 88 0e43f5c6 2011-10-05 rsc 		sysfatal("auth read in sign failed: %r");
 89 0e43f5c6 2011-10-05 rsc 
 90 0e43f5c6 2011-10-05 rsc 	print("-%s %.*H\n", id, rpc->narg, rpc->arg);
 91 0e43f5c6 2011-10-05 rsc 	threadexits(nil);
 92 0e43f5c6 2011-10-05 rsc }
 93 0e43f5c6 2011-10-05 rsc 
 94 0e43f5c6 2011-10-05 rsc static mpint*
 95 0e43f5c6 2011-10-05 rsc keytomp(Attr *a, char *name)
 96 0e43f5c6 2011-10-05 rsc {
 97 0e43f5c6 2011-10-05 rsc 	char *p;
 98 0e43f5c6 2011-10-05 rsc 	mpint *m;
 99 fa325e9b 2020-01-10 cross 
100 0e43f5c6 2011-10-05 rsc 	p = _strfindattr(a, name);
101 0e43f5c6 2011-10-05 rsc 	if(p == nil)
102 0e43f5c6 2011-10-05 rsc 		sysfatal("missing key attribute %s", name);
103 0e43f5c6 2011-10-05 rsc 	m = strtomp(p, nil, 16, nil);
104 0e43f5c6 2011-10-05 rsc 	if(m == nil)
105 0e43f5c6 2011-10-05 rsc 		sysfatal("malformed key attribute %s=%s", name, p);
106 0e43f5c6 2011-10-05 rsc 	return m;
107 0e43f5c6 2011-10-05 rsc }
108 0e43f5c6 2011-10-05 rsc 
109 0e43f5c6 2011-10-05 rsc static void
110 0e43f5c6 2011-10-05 rsc doVerify(void)
111 0e43f5c6 2011-10-05 rsc {
112 0e43f5c6 2011-10-05 rsc 	char *p;
113 0e43f5c6 2011-10-05 rsc 	int n, nsig;
114 0e43f5c6 2011-10-05 rsc 	Fmt fmt;
115 0e43f5c6 2011-10-05 rsc 	uchar digest[SHA1dlen], sig[1024];
116 0e43f5c6 2011-10-05 rsc 	char *text;
117 0e43f5c6 2011-10-05 rsc 	Attr *a;
118 0e43f5c6 2011-10-05 rsc 	DSAsig dsig;
119 0e43f5c6 2011-10-05 rsc 	DSApub dkey;
120 fa325e9b 2020-01-10 cross 
121 0e43f5c6 2011-10-05 rsc 	a = _parseattr(key);
122 0e43f5c6 2011-10-05 rsc 	if(a == nil)
123 0e43f5c6 2011-10-05 rsc 		sysfatal("invalid key");
124 0e43f5c6 2011-10-05 rsc 	dkey.alpha = keytomp(a, "alpha");
125 0e43f5c6 2011-10-05 rsc 	dkey.key = keytomp(a, "key");
126 0e43f5c6 2011-10-05 rsc 	dkey.p = keytomp(a, "p");
127 0e43f5c6 2011-10-05 rsc 	dkey.q = keytomp(a, "q");
128 0e43f5c6 2011-10-05 rsc 	if(!probably_prime(dkey.p, 20) && !probably_prime(dkey.q, 20))
129 0e43f5c6 2011-10-05 rsc 		sysfatal("p or q not prime");
130 0e43f5c6 2011-10-05 rsc 
131 0e43f5c6 2011-10-05 rsc 	while((p = getline(&n)) != nil)
132 0e43f5c6 2011-10-05 rsc 		if(p[0] == '+' && strcmp(p+1, id) == 0)
133 0e43f5c6 2011-10-05 rsc 			goto start;
134 0e43f5c6 2011-10-05 rsc 	sysfatal("no message found");
135 0e43f5c6 2011-10-05 rsc 
136 0e43f5c6 2011-10-05 rsc start:
137 0e43f5c6 2011-10-05 rsc 	fmtstrinit(&fmt);
138 0e43f5c6 2011-10-05 rsc 	while((p = getline(&n)) != nil) {
139 0e43f5c6 2011-10-05 rsc 		if(n >= 1+nid+1+16 && p[0] == '-' && strncmp(p+1, id, nid) == 0 && p[1+nid] == ' ') {
140 0e43f5c6 2011-10-05 rsc 			if((nsig = dec16(sig, sizeof sig, p+1+nid+1, n-(1+nid+1))) != 20+20)
141 0e43f5c6 2011-10-05 rsc 				sysfatal("malformed signture");
142 0e43f5c6 2011-10-05 rsc 			goto end;
143 0e43f5c6 2011-10-05 rsc 		}
144 0e43f5c6 2011-10-05 rsc 		if(p[0] == '+')
145 0e43f5c6 2011-10-05 rsc 			p++;
146 0e43f5c6 2011-10-05 rsc 		fmtprint(&fmt, "%s\n", p);
147 0e43f5c6 2011-10-05 rsc 	}
148 0e43f5c6 2011-10-05 rsc 	sysfatal("did not find end of message");
149 0cfb3760 2012-10-21 rsc 	return; // silence clang warning
150 0e43f5c6 2011-10-05 rsc 
151 0e43f5c6 2011-10-05 rsc end:
152 0e43f5c6 2011-10-05 rsc 	text = fmtstrflush(&fmt);
153 0e43f5c6 2011-10-05 rsc 	sha1((uchar*)text, strlen(text), digest, nil);
154 0e43f5c6 2011-10-05 rsc 
155 0e43f5c6 2011-10-05 rsc 	if(nsig != 40)
156 0e43f5c6 2011-10-05 rsc 		sysfatal("malformed signature");
157 0e43f5c6 2011-10-05 rsc 	dsig.r = betomp(sig, 20, nil);
158 0e43f5c6 2011-10-05 rsc 	dsig.s = betomp(sig+20, 20, nil);
159 0e43f5c6 2011-10-05 rsc 
160 0e43f5c6 2011-10-05 rsc 	if(dsaverify(&dkey, &dsig, betomp(digest, sizeof digest, nil)) < 0)
161 0e43f5c6 2011-10-05 rsc 		sysfatal("signature failed to verify: %r");
162 fa325e9b 2020-01-10 cross 
163 0e43f5c6 2011-10-05 rsc 	write(1, text, strlen(text));
164 0e43f5c6 2011-10-05 rsc 	threadexitsall(0);
165 0e43f5c6 2011-10-05 rsc }
166 0e43f5c6 2011-10-05 rsc 
167 0e43f5c6 2011-10-05 rsc char*
168 0e43f5c6 2011-10-05 rsc getline(int *np)
169 0e43f5c6 2011-10-05 rsc {
170 0e43f5c6 2011-10-05 rsc 	char *p;
171 0e43f5c6 2011-10-05 rsc 	int n;
172 fa325e9b 2020-01-10 cross 
173 0e43f5c6 2011-10-05 rsc 	if((p = Brdline(&b, '\n')) == nil)
174 0e43f5c6 2011-10-05 rsc 		return nil;
175 0e43f5c6 2011-10-05 rsc 	n = Blinelen(&b);
176 0e43f5c6 2011-10-05 rsc 	while(n > 0 && (p[n-1] == '\n' || p[n-1] == ' ' || p[n-1] == '\t'))
177 0e43f5c6 2011-10-05 rsc 		n--;
178 0e43f5c6 2011-10-05 rsc 	p[n] = '\0';
179 0e43f5c6 2011-10-05 rsc 	*np = n;
180 0e43f5c6 2011-10-05 rsc 	return p;
181 0e43f5c6 2011-10-05 rsc }