From: Andre Noll <maan@tuebingen.mpg.de>
Date: Tue, 28 Apr 2015 16:17:42 +0000 (+0200)
Subject: base64: Remove unnecessary overflow checks.
X-Git-Tag: v0.5.7~20^2~4
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=673f8dbef56bbe6a09870bdef65966db3f6793a2

base64: Remove unnecessary overflow checks.

Since we decode no more than encoded_size many bytes, and the output
buffer is allocated large enough to store the decoded data, we won't
ever overflow the output buffer. This commit removes the pointless
checks.
---

diff --git a/base64.c b/base64.c
index 4809a2f2..382f1519 100644
--- a/base64.c
+++ b/base64.c
@@ -46,12 +46,10 @@ int base64_decode(char const *src, size_t encoded_size, char **result,
 	char *pos;
 	const char *end = src + encoded_size;
 	unsigned char *target;
-	size_t targsize;
 
 	if (encoded_size == (size_t)-1)
 		encoded_size = strlen(src);
-	targsize = BASE64_MAX_DECODED_SIZE(encoded_size);
-	target = para_malloc(targsize + 1);
+	target = para_malloc(BASE64_MAX_DECODED_SIZE(encoded_size) + 1);
 
 	state = 0;
 	tarindex = 0;
@@ -70,30 +68,22 @@ int base64_decode(char const *src, size_t encoded_size, char **result,
 
 		switch (state) {
 		case 0:
-			if (tarindex >= targsize)
-				goto fail;
 			target[tarindex] = (pos - Base64) << 2;
 			state = 1;
 			break;
 		case 1:
-			if (tarindex + 1 >= targsize)
-				goto fail;
 			target[tarindex] |= (pos - Base64) >> 4;
 			target[tarindex + 1] = ((pos - Base64) & 0x0f) << 4;
 			tarindex++;
 			state = 2;
 			break;
 		case 2:
-			if (tarindex + 1 >= targsize)
-				goto fail;
 			target[tarindex] |= (pos - Base64) >> 2;
 			target[tarindex + 1] = ((pos - Base64) & 0x03) << 6;
 			tarindex++;
 			state = 3;
 			break;
 		case 3:
-			if (tarindex >= targsize)
-				goto fail;
 			target[tarindex] |= pos - Base64;
 			tarindex++;
 			state = 0;