diff options
| -rw-r--r-- | lib/base64.c | 47 |
1 files changed, 19 insertions, 28 deletions
diff --git a/lib/base64.c b/lib/base64.c index d0b49261a..af01f3a69 100644 --- a/lib/base64.c +++ b/lib/base64.c @@ -68,9 +68,13 @@ static size_t decodeQuantum(unsigned char *dest, const char *src) } } - dest[2] = curlx_ultouc(x & 0xFFUL); + if(padding < 2) + dest[2] = curlx_ultouc(x & 0xFFUL); + x >>= 8; - dest[1] = curlx_ultouc(x & 0xFFUL); + if(padding < 1) + dest[1] = curlx_ultouc(x & 0xFFUL); + x >>= 8; dest[0] = curlx_ultouc(x & 0xFFUL); @@ -94,23 +98,22 @@ static size_t decodeQuantum(unsigned char *dest, const char *src) CURLcode Curl_base64_decode(const char *src, unsigned char **outptr, size_t *outlen) { - size_t srcLen = 0; + size_t srclen = 0; size_t length = 0; - size_t equalsTerm = 0; + size_t padding = 0; size_t i; size_t result; size_t numQuantums; - unsigned char lastQuantum[3]; size_t rawlen = 0; unsigned char *pos; unsigned char *newstr; *outptr = NULL; *outlen = 0; - srcLen = strlen(src); + srclen = strlen(src); /* Check the length of the input string is valid */ - if(!srcLen || srcLen % 4) + if(!srclen || srclen % 4) return CURLE_BAD_CONTENT_ENCODING; /* Find the position of any = padding characters */ @@ -119,20 +122,20 @@ CURLcode Curl_base64_decode(const char *src, /* A maximum of two = padding characters is allowed */ if(src[length] == '=') { - equalsTerm++; - if(src[length+equalsTerm] == '=') - equalsTerm++; + padding++; + if(src[length + 1] == '=') + padding++; } /* Check the = padding characters weren't part way through the input */ - if(length + equalsTerm != srcLen) + if(length + padding != srclen) return CURLE_BAD_CONTENT_ENCODING; /* Calculate the number of quantums */ - numQuantums = srcLen / 4; + numQuantums = srclen / 4; /* Calculate the size of the decoded string */ - rawlen = (numQuantums * 3) - equalsTerm; + rawlen = (numQuantums * 3) - padding; /* Allocate our buffer including room for a zero terminator */ newstr = malloc(rawlen + 1); @@ -141,9 +144,8 @@ CURLcode Curl_base64_decode(const char *src, pos = newstr; - /* Decode all but the last quantum (which may not decode to a - multiple of 3 bytes) */ - for(i = 0; i < numQuantums - 1; i++) { + /* Decode the quantums */ + for(i = 0; i < numQuantums; i++) { result = decodeQuantum(pos, src); if(!result) { Curl_safefree(newstr); @@ -155,19 +157,8 @@ CURLcode Curl_base64_decode(const char *src, src += 4; } - /* Decode the last quantum */ - result = decodeQuantum(lastQuantum, src); - if(!result) { - Curl_safefree(newstr); - - return CURLE_BAD_CONTENT_ENCODING; - } - - for(i = 0; i < 3 - equalsTerm; i++) - pos[i] = lastQuantum[i]; - /* Zero terminate */ - pos[i] = '\0'; + *pos = '\0'; /* Return the decoded data */ *outptr = newstr; |