From 5957ec3c6deb0a5585f979ff470e9a346154ca62 Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@systemlinux.org>
Date: Mon, 7 Mar 2011 08:04:23 +0100
Subject: [PATCH] crypt: Make base64_decode public.

gcrypt.c needs this to decode public rsa keys. Public functions
should always return proper error codes, so change the return
value for errors from -1 to -E_BASE64.
---
 crypt_backend.h |  1 +
 crypt_common.c  | 28 ++++++++++++++--------------
 2 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/crypt_backend.h b/crypt_backend.h
index b362651d..3ea32c20 100644
--- a/crypt_backend.h
+++ b/crypt_backend.h
@@ -13,3 +13,4 @@ uint32_t read_ssh_u32(const void *vp);
 int uudecode(const char *src, unsigned char *target, size_t targsize);
 int check_ssh_key_header(const unsigned char *blob, int blen);
 int check_key_file(const char *file, bool private_key);
+int base64_decode(char const *src, unsigned char *target, size_t targsize);
diff --git a/crypt_common.c b/crypt_common.c
index 1308af41..3bd603c0 100644
--- a/crypt_common.c
+++ b/crypt_common.c
@@ -57,10 +57,10 @@ static const char Pad64 = '=';
 /*
  * Skips all whitespace anywhere. Converts characters, four at a time, starting
  * at (or after) src from base - 64 numbers into three 8 bit bytes in the
- * target area. it returns the number of data bytes stored at the target, or -1
+ * target area. it returns the number of data bytes stored at the target, or -E_BASE64
  * on error.
  */
-static int base64_decode(char const *src, unsigned char *target, size_t targsize)
+int base64_decode(char const *src, unsigned char *target, size_t targsize)
 {
 	unsigned int tarindex, state;
 	int ch;
@@ -78,13 +78,13 @@ static int base64_decode(char const *src, unsigned char *target, size_t targsize
 
 		pos = strchr(Base64, ch);
 		if (pos == 0) /* A non-base64 character. */
-			return -1;
+			return -E_BASE64;
 
 		switch (state) {
 		case 0:
 			if (target) {
 				if (tarindex >= targsize)
-					return (-1);
+					return -E_BASE64;
 				target[tarindex] = (pos - Base64) << 2;
 			}
 			state = 1;
@@ -92,7 +92,7 @@ static int base64_decode(char const *src, unsigned char *target, size_t targsize
 		case 1:
 			if (target) {
 				if (tarindex + 1 >= targsize)
-					return (-1);
+					return -E_BASE64;
 				target[tarindex]   |=  (pos - Base64) >> 4;
 				target[tarindex+1]  = ((pos - Base64) & 0x0f)
 							<< 4 ;
@@ -103,7 +103,7 @@ static int base64_decode(char const *src, unsigned char *target, size_t targsize
 		case 2:
 			if (target) {
 				if (tarindex + 1 >= targsize)
-					return (-1);
+					return -E_BASE64;
 				target[tarindex]   |=  (pos - Base64) >> 2;
 				target[tarindex+1]  = ((pos - Base64) & 0x03)
 							<< 6;
@@ -114,7 +114,7 @@ static int base64_decode(char const *src, unsigned char *target, size_t targsize
 		case 3:
 			if (target) {
 				if (tarindex >= targsize)
-					return (-1);
+					return -E_BASE64;
 				target[tarindex] |= (pos - Base64);
 			}
 			tarindex++;
@@ -133,7 +133,7 @@ static int base64_decode(char const *src, unsigned char *target, size_t targsize
 		switch (state) {
 		case 0:		/* Invalid = in first position */
 		case 1:		/* Invalid = in second position */
-			return (-1);
+			return -E_BASE64;
 
 		case 2:		/* Valid, means one byte of info */
 			/* Skip any number of spaces. */
@@ -142,7 +142,7 @@ static int base64_decode(char const *src, unsigned char *target, size_t targsize
 					break;
 			/* Make sure there is another trailing = sign. */
 			if (ch != Pad64)
-				return (-1);
+				return -E_BASE64;
 			ch = *src++;		/* Skip the = */
 			/* Fall through to "single trailing =" case. */
 			/* FALLTHROUGH */
@@ -154,7 +154,7 @@ static int base64_decode(char const *src, unsigned char *target, size_t targsize
 			 */
 			for (; ch != '\0'; ch = *src++)
 				if (!isspace(ch))
-					return (-1);
+					return -E_BASE64;
 
 			/*
 			 * Now make sure for cases 2 and 3 that the "extra"
@@ -163,7 +163,7 @@ static int base64_decode(char const *src, unsigned char *target, size_t targsize
 			 * subliminal channel.
 			 */
 			if (target && target[tarindex] != 0)
-				return (-1);
+				return -E_BASE64;
 		}
 	} else {
 		/*
@@ -171,10 +171,10 @@ static int base64_decode(char const *src, unsigned char *target, size_t targsize
 		 * have no partial bytes lying around.
 		 */
 		if (state != 0)
-			return (-1);
+			return -E_BASE64;
 	}
 
-	return (tarindex);
+	return tarindex;
 }
 
 int uudecode(const char *src, unsigned char *target, size_t targsize)
@@ -193,7 +193,7 @@ int uudecode(const char *src, unsigned char *target, size_t targsize)
 	*p = '\0';
 	len = base64_decode(encoded, target, targsize);
 	free(encoded);
-	return len >= 0? len : -E_BASE64;
+	return len;
 }
 
 /*
-- 
2.39.5