diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/x25/x25_facilities.c |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'net/x25/x25_facilities.c')
-rw-r--r-- | net/x25/x25_facilities.c | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/net/x25/x25_facilities.c b/net/x25/x25_facilities.c new file mode 100644 index 000000000000..a21bdb95f9a8 --- /dev/null +++ b/net/x25/x25_facilities.c | |||
@@ -0,0 +1,231 @@ | |||
1 | /* | ||
2 | * X.25 Packet Layer release 002 | ||
3 | * | ||
4 | * This is ALPHA test software. This code may break your machine, | ||
5 | * randomly fail to work with new releases, misbehave and/or generally | ||
6 | * screw up. It might even work. | ||
7 | * | ||
8 | * This code REQUIRES 2.1.15 or higher | ||
9 | * | ||
10 | * This module: | ||
11 | * This module is free software; you can redistribute it and/or | ||
12 | * modify it under the terms of the GNU General Public License | ||
13 | * as published by the Free Software Foundation; either version | ||
14 | * 2 of the License, or (at your option) any later version. | ||
15 | * | ||
16 | * History | ||
17 | * X.25 001 Split from x25_subr.c | ||
18 | * mar/20/00 Daniela Squassoni Disabling/enabling of facilities | ||
19 | * negotiation. | ||
20 | */ | ||
21 | |||
22 | #include <linux/kernel.h> | ||
23 | #include <linux/string.h> | ||
24 | #include <linux/skbuff.h> | ||
25 | #include <net/sock.h> | ||
26 | #include <net/x25.h> | ||
27 | |||
28 | /* | ||
29 | * Parse a set of facilities into the facilities structure. Unrecognised | ||
30 | * facilities are written to the debug log file. | ||
31 | */ | ||
32 | int x25_parse_facilities(struct sk_buff *skb, | ||
33 | struct x25_facilities *facilities, | ||
34 | unsigned long *vc_fac_mask) | ||
35 | { | ||
36 | unsigned char *p = skb->data; | ||
37 | unsigned int len = *p++; | ||
38 | |||
39 | *vc_fac_mask = 0; | ||
40 | |||
41 | while (len > 0) { | ||
42 | switch (*p & X25_FAC_CLASS_MASK) { | ||
43 | case X25_FAC_CLASS_A: | ||
44 | switch (*p) { | ||
45 | case X25_FAC_REVERSE: | ||
46 | facilities->reverse = p[1] & 0x01; | ||
47 | *vc_fac_mask |= X25_MASK_REVERSE; | ||
48 | break; | ||
49 | case X25_FAC_THROUGHPUT: | ||
50 | facilities->throughput = p[1]; | ||
51 | *vc_fac_mask |= X25_MASK_THROUGHPUT; | ||
52 | break; | ||
53 | default: | ||
54 | printk(KERN_DEBUG "X.25: unknown facility " | ||
55 | "%02X, value %02X\n", | ||
56 | p[0], p[1]); | ||
57 | break; | ||
58 | } | ||
59 | p += 2; | ||
60 | len -= 2; | ||
61 | break; | ||
62 | case X25_FAC_CLASS_B: | ||
63 | switch (*p) { | ||
64 | case X25_FAC_PACKET_SIZE: | ||
65 | facilities->pacsize_in = p[1]; | ||
66 | facilities->pacsize_out = p[2]; | ||
67 | *vc_fac_mask |= X25_MASK_PACKET_SIZE; | ||
68 | break; | ||
69 | case X25_FAC_WINDOW_SIZE: | ||
70 | facilities->winsize_in = p[1]; | ||
71 | facilities->winsize_out = p[2]; | ||
72 | *vc_fac_mask |= X25_MASK_WINDOW_SIZE; | ||
73 | break; | ||
74 | default: | ||
75 | printk(KERN_DEBUG "X.25: unknown facility " | ||
76 | "%02X, values %02X, %02X\n", | ||
77 | p[0], p[1], p[2]); | ||
78 | break; | ||
79 | } | ||
80 | p += 3; | ||
81 | len -= 3; | ||
82 | break; | ||
83 | case X25_FAC_CLASS_C: | ||
84 | printk(KERN_DEBUG "X.25: unknown facility %02X, " | ||
85 | "values %02X, %02X, %02X\n", | ||
86 | p[0], p[1], p[2], p[3]); | ||
87 | p += 4; | ||
88 | len -= 4; | ||
89 | break; | ||
90 | case X25_FAC_CLASS_D: | ||
91 | printk(KERN_DEBUG "X.25: unknown facility %02X, " | ||
92 | "length %d, values %02X, %02X, %02X, %02X\n", | ||
93 | p[0], p[1], p[2], p[3], p[4], p[5]); | ||
94 | len -= p[1] + 2; | ||
95 | p += p[1] + 2; | ||
96 | break; | ||
97 | } | ||
98 | } | ||
99 | |||
100 | return p - skb->data; | ||
101 | } | ||
102 | |||
103 | /* | ||
104 | * Create a set of facilities. | ||
105 | */ | ||
106 | int x25_create_facilities(unsigned char *buffer, | ||
107 | struct x25_facilities *facilities, | ||
108 | unsigned long facil_mask) | ||
109 | { | ||
110 | unsigned char *p = buffer + 1; | ||
111 | int len; | ||
112 | |||
113 | if (!facil_mask) { | ||
114 | /* | ||
115 | * Length of the facilities field in call_req or | ||
116 | * call_accept packets | ||
117 | */ | ||
118 | buffer[0] = 0; | ||
119 | len = 1; /* 1 byte for the length field */ | ||
120 | return len; | ||
121 | } | ||
122 | |||
123 | if (facilities->reverse && (facil_mask & X25_MASK_REVERSE)) { | ||
124 | *p++ = X25_FAC_REVERSE; | ||
125 | *p++ = !!facilities->reverse; | ||
126 | } | ||
127 | |||
128 | if (facilities->throughput && (facil_mask & X25_MASK_THROUGHPUT)) { | ||
129 | *p++ = X25_FAC_THROUGHPUT; | ||
130 | *p++ = facilities->throughput; | ||
131 | } | ||
132 | |||
133 | if ((facilities->pacsize_in || facilities->pacsize_out) && | ||
134 | (facil_mask & X25_MASK_PACKET_SIZE)) { | ||
135 | *p++ = X25_FAC_PACKET_SIZE; | ||
136 | *p++ = facilities->pacsize_in ? : facilities->pacsize_out; | ||
137 | *p++ = facilities->pacsize_out ? : facilities->pacsize_in; | ||
138 | } | ||
139 | |||
140 | if ((facilities->winsize_in || facilities->winsize_out) && | ||
141 | (facil_mask & X25_MASK_WINDOW_SIZE)) { | ||
142 | *p++ = X25_FAC_WINDOW_SIZE; | ||
143 | *p++ = facilities->winsize_in ? : facilities->winsize_out; | ||
144 | *p++ = facilities->winsize_out ? : facilities->winsize_in; | ||
145 | } | ||
146 | |||
147 | len = p - buffer; | ||
148 | buffer[0] = len - 1; | ||
149 | |||
150 | return len; | ||
151 | } | ||
152 | |||
153 | /* | ||
154 | * Try to reach a compromise on a set of facilities. | ||
155 | * | ||
156 | * The only real problem is with reverse charging. | ||
157 | */ | ||
158 | int x25_negotiate_facilities(struct sk_buff *skb, struct sock *sk, | ||
159 | struct x25_facilities *new) | ||
160 | { | ||
161 | struct x25_sock *x25 = x25_sk(sk); | ||
162 | struct x25_facilities *ours = &x25->facilities; | ||
163 | struct x25_facilities theirs; | ||
164 | int len; | ||
165 | |||
166 | memset(&theirs, 0, sizeof(theirs)); | ||
167 | memcpy(new, ours, sizeof(*new)); | ||
168 | |||
169 | len = x25_parse_facilities(skb, &theirs, &x25->vc_facil_mask); | ||
170 | |||
171 | /* | ||
172 | * They want reverse charging, we won't accept it. | ||
173 | */ | ||
174 | if (theirs.reverse && ours->reverse) { | ||
175 | SOCK_DEBUG(sk, "X.25: rejecting reverse charging request"); | ||
176 | return -1; | ||
177 | } | ||
178 | |||
179 | new->reverse = theirs.reverse; | ||
180 | |||
181 | if (theirs.throughput) { | ||
182 | if (theirs.throughput < ours->throughput) { | ||
183 | SOCK_DEBUG(sk, "X.25: throughput negotiated down"); | ||
184 | new->throughput = theirs.throughput; | ||
185 | } | ||
186 | } | ||
187 | |||
188 | if (theirs.pacsize_in && theirs.pacsize_out) { | ||
189 | if (theirs.pacsize_in < ours->pacsize_in) { | ||
190 | SOCK_DEBUG(sk, "X.25: packet size inwards negotiated down"); | ||
191 | new->pacsize_in = theirs.pacsize_in; | ||
192 | } | ||
193 | if (theirs.pacsize_out < ours->pacsize_out) { | ||
194 | SOCK_DEBUG(sk, "X.25: packet size outwards negotiated down"); | ||
195 | new->pacsize_out = theirs.pacsize_out; | ||
196 | } | ||
197 | } | ||
198 | |||
199 | if (theirs.winsize_in && theirs.winsize_out) { | ||
200 | if (theirs.winsize_in < ours->winsize_in) { | ||
201 | SOCK_DEBUG(sk, "X.25: window size inwards negotiated down"); | ||
202 | new->winsize_in = theirs.winsize_in; | ||
203 | } | ||
204 | if (theirs.winsize_out < ours->winsize_out) { | ||
205 | SOCK_DEBUG(sk, "X.25: window size outwards negotiated down"); | ||
206 | new->winsize_out = theirs.winsize_out; | ||
207 | } | ||
208 | } | ||
209 | |||
210 | return len; | ||
211 | } | ||
212 | |||
213 | /* | ||
214 | * Limit values of certain facilities according to the capability of the | ||
215 | * currently attached x25 link. | ||
216 | */ | ||
217 | void x25_limit_facilities(struct x25_facilities *facilities, | ||
218 | struct x25_neigh *nb) | ||
219 | { | ||
220 | |||
221 | if (!nb->extended) { | ||
222 | if (facilities->winsize_in > 7) { | ||
223 | printk(KERN_DEBUG "X.25: incoming winsize limited to 7\n"); | ||
224 | facilities->winsize_in = 7; | ||
225 | } | ||
226 | if (facilities->winsize_out > 7) { | ||
227 | facilities->winsize_out = 7; | ||
228 | printk( KERN_DEBUG "X.25: outgoing winsize limited to 7\n"); | ||
229 | } | ||
230 | } | ||
231 | } | ||