devs/libstrophe-gh
2
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

base64: fixed crash when len is small

Browse Source
This commit is contained in:
Dmitry Podgorny
2015-10-13 23:20:41 +03:00
parent e0a13ecdaa
commit b5e49a0600
1 changed files with 5 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
src/sasl.c
View File

@@ -516,7 +516,7 @@ char *base64_encode(xmpp_ctx_t *ctx,
if (cbuf != NULL) { if (cbuf != NULL) {
c = cbuf; c = cbuf;
/* loop over data, turning every 3 bytes into 4 characters */ /* loop over data, turning every 3 bytes into 4 characters */
for (i = 0; i < len - 2; i += 3) { for (i = 0; i + 2 < len; i += 3) {
word = buffer[i] << 16 | buffer[i+1] << 8 | buffer[i+2]; word = buffer[i] << 16 | buffer[i+1] << 8 | buffer[i+2];
hextet = (word & 0x00FC0000) >> 18; hextet = (word & 0x00FC0000) >> 18;
*c++ = _base64_charmap[hextet]; *c++ = _base64_charmap[hextet];
@@ -563,6 +563,8 @@ int base64_decoded_len(xmpp_ctx_t *ctx,
int nudge; int nudge;
int c; int c;
if (len < 4) return 0;
/* count the padding characters for the remainder */ /* count the padding characters for the remainder */
nudge = -1; nudge = -1;
c = _base64_invcharmap[(int)buffer[len-1]]; c = _base64_invcharmap[(int)buffer[len-1]];
@@ -586,7 +588,7 @@ unsigned char *base64_decode(xmpp_ctx_t *ctx,
{ {
int dlen; int dlen;
unsigned char *dbuf, *d; unsigned char *dbuf, *d;
uint32_t word, hextet; uint32_t word, hextet = 0;
unsigned i; unsigned i;
/* len must be a multiple of 4 */ /* len must be a multiple of 4 */
@@ -597,7 +599,7 @@ unsigned char *base64_decode(xmpp_ctx_t *ctx,
if (dbuf != NULL) { if (dbuf != NULL) {
d = dbuf; d = dbuf;
/* loop over each set of 4 characters, decoding 3 bytes */ /* loop over each set of 4 characters, decoding 3 bytes */
for (i = 0; i < len - 3; i += 4) { for (i = 0; i + 3 < len; i += 4) {
hextet = _base64_invcharmap[(int)buffer[i]]; hextet = _base64_invcharmap[(int)buffer[i]];
if (hextet & 0xC0) break; if (hextet & 0xC0) break;
word = hextet << 18; word = hextet << 18;