[libotr] * added patch for https://bugzilla.redhat.com/show_bug.cgi?id=846377

[Paul Wouters]

commit a4a15e5429ebf67b3f3b4713303f7647d3aaaa0c
Author: Paul Wouters <pwouters at redhat.com>
Date:   Wed Aug 8 12:16:30 2012 -0400

    * added patch for https://bugzilla.redhat.com/show_bug.cgi?id=846377

 libotr-3.2.0-846377.patch |  154 +++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 154 insertions(+), 0 deletions(-)
---
diff --git a/libotr-3.2.0-846377.patch b/libotr-3.2.0-846377.patch
new file mode 100644
index 0000000..6512fa2
--- /dev/null
+++ b/libotr-3.2.0-846377.patch
@@ -0,0 +1,154 @@
+diff --git a/src/b64.c b/src/b64.c
+index b8736da..9e35251 100644
+--- a/src/b64.c
++++ b/src/b64.c
+@@ -55,7 +55,7 @@ VERSION HISTORY:
+ \******************************************************************* */
+ 
+ /* system headers */
+-#include <stdlib.h>
++#include <stdio.h>
+ #include <string.h>
+ 
+ /* libotr headers */
+@@ -147,8 +147,9 @@ static size_t decode(unsigned char *out, const char *in, size_t b64len)
+  * base64 decode data.  Skip non-base64 chars, and terminate at the
+  * first '=', or the end of the buffer.
+  *
+- * The buffer data must contain at least (base64len / 4) * 3 bytes of
+- * space.  This function will return the number of bytes actually used.
++ * The buffer data must contain at least ((base64len+3) / 4) * 3 bytes
++ * of space.  This function will return the number of bytes actually
++ * used.
+  */
+ size_t otrl_base64_decode(unsigned char *data, const char *base64data,
+ 	size_t base64len)
+@@ -234,13 +235,18 @@ int otrl_base64_otr_decode(const char *msg, unsigned char **bufp,
+ 	return -2;
+     }
+ 
++    /* Skip over the "?OTR:" */
++    otrtag += 5;
++    msglen -= 5;
++
+     /* Base64-decode the message */
+-    rawlen = ((msglen-5) / 4) * 3;   /* maximum possible */
++    rawlen = OTRL_B64_MAX_DECODED_SIZE(msglen);   /* maximum possible */
+     rawmsg = malloc(rawlen);
+     if (!rawmsg && rawlen > 0) {
+ 	return -1;
+     }
+-    rawlen = otrl_base64_decode(rawmsg, otrtag+5, msglen-5);  /* actual size */
++
++    rawlen = otrl_base64_decode(rawmsg, otrtag, msglen);  /* actual size */
+ 
+     *bufp = rawmsg;
+     *lenp = rawlen;
+diff --git a/src/b64.h b/src/b64.h
+index 34ef03f..dd0e115 100644
+--- a/src/b64.h
++++ b/src/b64.h
+@@ -20,6 +20,19 @@
+ #ifndef __B64_H__
+ #define __B64_H__
+ 
++#include <stdlib.h>
++
++/* Base64 encodes blocks of this many bytes: */
++#define OTRL_B64_DECODED_LEN 3
++/* into blocks of this many bytes: */
++#define OTRL_B64_ENCODED_LEN 4
++
++/* An encoded block of length encoded_len can turn into a maximum of
++ * this many decoded bytes: */
++#define OTRL_B64_MAX_DECODED_SIZE(encoded_len) \
++    (((encoded_len + OTRL_B64_ENCODED_LEN - 1) / OTRL_B64_ENCODED_LEN) \
++	* OTRL_B64_DECODED_LEN)
++
+ /*
+  * base64 encode data.  Insert no linebreaks or whitespace.
+  *
+@@ -33,8 +46,9 @@ size_t otrl_base64_encode(char *base64data, const unsigned char *data,
+  * base64 decode data.  Skip non-base64 chars, and terminate at the
+  * first '=', or the end of the buffer.
+  *
+- * The buffer data must contain at least (base64len / 4) * 3 bytes of
+- * space.  This function will return the number of bytes actually used.
++ * The buffer data must contain at least ((base64len+3) / 4) * 3 bytes
++ * of space.  This function will return the number of bytes actually
++ * used.
+  */
+ size_t otrl_base64_decode(unsigned char *data, const char *base64data,
+ 	size_t base64len);
+diff --git a/src/proto.c b/src/proto.c
+index 3f8c987..0374dfe 100644
+--- a/src/proto.c
++++ b/src/proto.c
+@@ -537,13 +537,17 @@ gcry_error_t otrl_proto_data_read_flags(const char *datamsg,
+ 	msglen = strlen(otrtag);
+     }
+ 
++    /* Skip over the "?OTR:" */
++    otrtag += 5;
++    msglen -= 5;
++
+     /* Base64-decode the message */
+-    rawlen = ((msglen-5) / 4) * 3;   /* maximum possible */
++    rawlen = OTRL_B64_MAX_DECODED_SIZE(msglen);   /* maximum possible */
+     rawmsg = malloc(rawlen);
+     if (!rawmsg && rawlen > 0) {
+ 	return gcry_error(GPG_ERR_ENOMEM);
+     }
+-    rawlen = otrl_base64_decode(rawmsg, otrtag+5, msglen-5);  /* actual size */
++    rawlen = otrl_base64_decode(rawmsg, otrtag, msglen);  /* actual size */
+ 
+     bufp = rawmsg;
+     lenp = rawlen;
+@@ -606,14 +610,18 @@ gcry_error_t otrl_proto_accept_data(char **plaintextp, OtrlTLV **tlvsp,
+ 	msglen = strlen(otrtag);
+     }
+ 
++    /* Skip over the "?OTR:" */
++    otrtag += 5;
++    msglen -= 5;
++
+     /* Base64-decode the message */
+-    rawlen = ((msglen-5) / 4) * 3;   /* maximum possible */
++    rawlen = OTRL_B64_MAX_DECODED_SIZE(msglen);   /* maximum possible */
+     rawmsg = malloc(rawlen);
+     if (!rawmsg && rawlen > 0) {
+ 	err = gcry_error(GPG_ERR_ENOMEM);
+ 	goto err;
+     }
+-    rawlen = otrl_base64_decode(rawmsg, otrtag+5, msglen-5);  /* actual size */
++    rawlen = otrl_base64_decode(rawmsg, otrtag, msglen);  /* actual size */
+ 
+     bufp = rawmsg;
+     lenp = rawlen;
+diff --git a/toolkit/parse.c b/toolkit/parse.c
+index 5f357fc..16718ca 100644
+--- a/toolkit/parse.c
++++ b/toolkit/parse.c
+@@ -64,7 +64,8 @@ static unsigned char *decode(const char *msg, size_t *lenp)
+ {
+     const char *header, *footer;
+     unsigned char *raw;
+-	
++    size_t rawlen;
++
+     /* Find the header */
+     header = strstr(msg, "?OTR:");
+     if (!header) return NULL;
+@@ -75,8 +76,10 @@ static unsigned char *decode(const char *msg, size_t *lenp)
+     footer = strchr(header, '.');
+     if (!footer) footer = header + strlen(header);
+ 
+-    raw = malloc((footer-header) / 4 * 3);
+-    if (raw == NULL && (footer-header >= 4)) return NULL;
++    rawlen = OTRL_B64_MAX_DECODED_SIZE(footer-header);
++
++    raw = malloc(rawlen);
++    if (raw == NULL && rawlen > 0) return NULL;
+     *lenp = otrl_base64_decode(raw, header, footer-header);
+ 
+     return raw;