mir/isc-dhcp
2
0
Fork 0
mirror of https://gitlab.isc.org/isc-projects/dhcp synced 2025-08-31 22:35:25 +00:00
Code Issues Releases Wiki Activity

Fix base64 decoder.

Browse Source
This commit is contained in:
Ted Lemon
2000-09-01 23:07:35 +00:00
parent addb00afe9
commit 8f01f9ec85
1 changed files with 89 additions and 32 deletions
Download Patch File Download Diff File Expand all files Collapse all files

121
common/parse.c
View File

@@ -43,7 +43,7 @@
#ifndef lint #ifndef lint
static char copyright[] = static char copyright[] =
"$Id: parse.c,v 1.81 2000/08/28 21:22:34 neild Exp $ Copyright (c) 1995-2000 The Internet Software Consortium. All rights reserved.\n"; "$Id: parse.c,v 1.82 2000/09/01 23:07:35 mellon Exp $ Copyright (c) 1995-2000 The Internet Software Consortium. All rights reserved.\n";
#endif /* not lint */ #endif /* not lint */
#include "dhcpd.h" #include "dhcpd.h"
@@ -1137,7 +1137,7 @@ int parse_base64 (data, cfile)
{ {
enum dhcp_token token; enum dhcp_token token;
const char *val; const char *val;
int i, j; int i, j, k;
unsigned acc = 0; unsigned acc = 0;
static unsigned char static unsigned char
from64 [] = {64, 64, 64, 64, 64, 64, 64, 64, /* \"#$%&' */ from64 [] = {64, 64, 64, 64, 64, 64, 64, 64, /* \"#$%&' */
@@ -1152,9 +1152,15 @@ int parse_base64 (data, cfile)
33, 34, 35, 36, 37, 38, 39, 40, /* hijklmno */ 33, 34, 35, 36, 37, 38, 39, 40, /* hijklmno */
41, 42, 43, 44, 45, 46, 47, 48, /* pqrstuvw */ 41, 42, 43, 44, 45, 46, 47, 48, /* pqrstuvw */
59, 50, 51, 64, 64, 64, 64, 64}; /* xyz{|}~ */ 59, 50, 51, 64, 64, 64, 64, 64}; /* xyz{|}~ */
struct string_list *bufs = (struct string_list *)0,
*last = (struct string_list *)0,
*t;
int cc = 0;
int terminated = 0;
token = next_token (&val, cfile); token = peek_token (&val, cfile);
if (token == STRING) { if (token == STRING) {
token = next_token (&val, cfile);
data -> len = strlen (val) + 1; data -> len = strlen (val) + 1;
if (!buffer_allocate (&data -> buffer, data -> len, MDL)) { if (!buffer_allocate (&data -> buffer, data -> len, MDL)) {
parse_warn (cfile, "can't allocate string buffer"); parse_warn (cfile, "can't allocate string buffer");
@@ -1166,7 +1172,30 @@ int parse_base64 (data, cfile)
return 1; return 1;
} }
data -> len = strlen (val); /* It's possible for a + or a / to cause a base64 quantity to be
tokenized into more than one token, so we have to parse them all
in before decoding. */
do {
int l;
token = next_token (&val, cfile);
l = strlen (val);
t = dmalloc (l + sizeof *t, MDL);
if (!t)
log_fatal ("no memory for base64 buffer.");
memset (t, 0, (sizeof *t) - 1);
strcpy (t -> string, val);
cc += l;
if (last)
last -> next = t;
else
bufs = t;
last = t;
token = peek_token (&val, cfile);
} while (token == NUMBER_OR_NAME || token == NAME || token == EQUAL ||
token == NUMBER || token == PLUS || token == SLASH);
data -> len = cc;
data -> len = (data -> len * 3) / 4; data -> len = (data -> len * 3) / 4;
if (!buffer_allocate (&data -> buffer, data -> len, MDL)) { if (!buffer_allocate (&data -> buffer, data -> len, MDL)) {
parse_warn (cfile, "can't allocate buffer for base64 data."); parse_warn (cfile, "can't allocate buffer for base64 data.");
@@ -1175,43 +1204,71 @@ int parse_base64 (data, cfile)
return 0; return 0;
} }
j = 0; j = k = 0;
for (i = 0; val [i] != '=' && val [i]; i++) { for (t = bufs; t; t = t -> next) {
unsigned foo = val [i]; for (i = 0; t -> string [i]; i++) {
unsigned foo = t -> string [i];
if (terminated && foo != '=') {
parse_warn (cfile,
"stuff after base64 '=' terminator: %s.",
&t -> string [i]);
goto bad;
}
if (foo < ' ' || foo > 'z') { if (foo < ' ' || foo > 'z') {
bad64: bad64:
parse_warn (cfile, parse_warn (cfile,
"invalid base64 character %d.", val [i]); "invalid base64 character %d.",
t -> string [i]);
bad:
data_string_forget (data, MDL); data_string_forget (data, MDL);
return 0; goto out;
} }
foo = from64 [foo - ' ']; if (foo == '=')
if (foo == 64) terminated = 1;
goto bad64; else {
acc = (acc << 6) + foo; foo = from64 [foo - ' '];
switch (i % 4) { if (foo == 64)
case 0: goto bad64;
break; acc = (acc << 6) + foo;
case 1: switch (k % 4) {
data -> buffer -> data [j++] = (acc >> 4); case 0:
acc = acc & 0x0f; break;
break; case 1:
data -> buffer -> data [j++] = (acc >> 4);
case 2: acc = acc & 0x0f;
data -> buffer -> data [j++] = (acc >> 2); break;
acc = acc & 0x03;
break; case 2:
case 3: data -> buffer -> data [j++] = (acc >> 2);
data -> buffer -> data [j++] = acc; acc = acc & 0x03;
acc = 0; break;
break; case 3:
data -> buffer -> data [j++] = acc;
acc = 0;
break;
}
}
k++;
}
}
if (k % 4) {
if (acc) {
parse_warn (cfile,
"partial base64 value left over: %d.",
acc);
} }
} }
if (i % 4)
parse_warn (cfile, "partial base64 value left over: %d.", acc);
data -> len = j; data -> len = j;
data -> data = data -> buffer -> data; data -> data = data -> buffer -> data;
return 1; out:
for (t = bufs; t; t = last) {
last = t -> next;
dfree (t, MDL);
}
if (data -> len)
return 1;
else
return 0;
} }