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-rw-r--r--third_party/sipcc/sdp_base64.c403
1 files changed, 403 insertions, 0 deletions
diff --git a/third_party/sipcc/sdp_base64.c b/third_party/sipcc/sdp_base64.c
new file mode 100644
index 0000000000..80f1eb52da
--- /dev/null
+++ b/third_party/sipcc/sdp_base64.c
@@ -0,0 +1,403 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "sdp_base64.h"
+
+/*
+ * Local definitions for Base64 to Raw table entries.
+ */
+#define INVALID_CHAR 0xFF /* Character not in supported Base64 set */
+#define WHITE_SPACE 0xFE /* Space, tab, newline, etc character */
+#define PADDING 0xFD /* The character '=' */
+
+#define PAD_CHAR '=' /* The character '=' */
+
+/* Maximum length of a base64 encoded line */
+#define MAX_BASE64_LINE_LENGTH 76
+
+/*
+ * base64_result_table
+ * String table for translating base64 error codes into human
+ * understanable strings.
+ */
+char *base64_result_table[BASE64_RESULT_MAX] =
+{
+ "Base64 successful",
+ "Base64 Buffer Overrun",
+ "Base64 Bad Data",
+ "Base64 Bad Padding",
+ "Base64 Bad Block Size"
+};
+
+/*
+ * base64_to_raw_table
+ * Heart of the Base64 decoding algorithm. Lookup table to convert
+ * the Base64 characters into their specified representative values.
+ * Invalid characters are marked with 0xFF, white space characters
+ * are marked with 0xFE, and the special pading character is marked
+ * with 0xFD.
+ */
+unsigned char base64_to_raw_table[128] =
+{
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, /* 0-9 */
+ 0xFE, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, /* 10-19 */
+ 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, /* 20-29 */
+ 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, /* 30-39 */
+ 0xFF, 0xFF, 0xFF, 62, 0xFF, 0xFF, 0xFF, 63, 52, 53, /* 40-49 */
+ 54, 55, 56, 57, 58, 59, 60, 61, 0xFF, 0xFF, /* 50-59 */
+ 0xFF, 0xFD, 0xFF, 0xFF, 0xFF, 0, 1, 2, 3, 4, /* 60-69 */
+ 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, /* 70-79 */
+ 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, /* 80-89 */
+ 25, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 26, 27, 28, /* 90-99 */
+ 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, /* 100-109 */
+ 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, /* 110-119 */
+ 49, 50, 51, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF /* 120-127 */
+};
+
+unsigned char raw_to_base64_table[64] =
+{
+ 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', /* 0-9 */
+ 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', /* 10-19 */
+ 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', /* 20-29 */
+ 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', /* 30-39 */
+ 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', /* 40-49 */
+ 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', /* 50-59 */
+ '8', '9', '+', '/' /* 60-63 */
+};
+
+/*
+ * base64_encode_size_bytes
+ *
+ * DESCRIPTION
+ * Estimates the size of buffer required for holding the result of
+ * encoding data of size raw_size_bytes.
+ *
+ * PARAMETERS
+ * raw_size_bytes = Estimated size of the un-encoded data in bytes.
+ *
+ * RETURN VALUE
+ * The size of destination buffer to use for encoding in bytes.
+ */
+int base64_est_encode_size_bytes (int raw_size_bytes)
+{
+ int length;
+
+ /*
+ * Find the number of bytes needed to represent the data
+ * using a 4/3 expansion ratio. That result must be
+ * rounded to the next higher multiple of four to account
+ * for padding. Then add in a term to account for any '\n's
+ * added.
+ */
+ length = ((((raw_size_bytes * 4 + 2)/ 3) + 3) & ~(0x3)) +
+ raw_size_bytes / MAX_BASE64_LINE_LENGTH;
+
+ return length;
+}
+
+/*
+ * base64_decode_size_bytes
+ *
+ * DESCRIPTION
+ * Estimates the size of buffer required for holding the result of
+ * decoding data of size base64_size_bytes.
+ *
+ * PARAMETERS
+ * base64_size_bytes = Estimated size of the Base64 data in bytes.
+ *
+ * RETURN VALUE
+ * The size of destination buffer to use for decoding in bytes.
+ */
+int base64_est_decode_size_bytes (int base64_size_bytes)
+{
+ int length;
+
+ length = (base64_size_bytes * 3 + 3) / 4;
+ return length;
+}
+
+/*
+ * base64_encode
+ *
+ * DESCRIPTION
+ * Encode data pointed to by src into the buffer pointer to by dest
+ * using the Base64 algorithm.
+ *
+ * NOTE: No trailing '\n' character will be added.
+ *
+ * NOTE: As per specification, '\n' will be placed every 76 chars.
+ *
+ * PARAMETERS
+ * src = Pointer to the raw data to base64 encode.
+ * src_bytes = The number of bytes in the src buffer to encode.
+ * dest = Pointer to the destination buffer where the converted data
+ * will reside when complete.
+ * dest_bytes = Initially holds the size of the destination buffer
+ * but at completion holds the number of bytes converted.
+ *
+ * RETURN VALUE
+ * base64_success if the buffer was successfully converted, the
+ * appropriate error code otherwise.
+ *
+ * The dest parameter holds the converted data.
+ *
+ * The dest_bytes parameter holds the actual number of bytes converted.
+ */
+base64_result_t base64_encode(unsigned char *src, int src_bytes, unsigned char *dest, int *dest_bytes)
+{
+ int i, j=0;
+ int line_count = 0;
+ unsigned char index; /* index into base64 lookup table */
+ int smax = src_bytes-2; /* only do full multiples of 3 */
+ int dmax = *dest_bytes; /* destination maximum */
+
+ *dest_bytes = 0;
+
+ /* Do full groups. Base64 must be done in blocks of 3 src bytes */
+ for (i=0; i<smax; i+=3) {
+ /* Check to see if newline should be injected */
+ if (line_count>=MAX_BASE64_LINE_LENGTH) {
+ if (j<dmax){
+ dest[j++] = '\n';
+ } else {
+ return BASE64_BUFFER_OVERRUN;
+ }
+ line_count = 0;
+ }
+
+ line_count += 4;
+
+ if ((j+3) < dmax) {
+
+ /* Find mapping of upper 6 bits */
+ index = (src[i] >> 2) & 0x3F;
+ dest[j++] = raw_to_base64_table[index];
+
+ /* bottom 2 bits of first word, high 4 bits of second word */
+ index = ((src[i] << 4) & 0x30) | ((src[i+1] >> 4) & 0x0F);
+ dest[j++] = raw_to_base64_table[index];
+
+ /* bottom 4 bits of second word, high 2 bits of third word */
+ index = ((src[i+1] << 2) & 0x3C) | ((src[i+2] >> 6) & 0x03);
+ dest[j++] = raw_to_base64_table[index];
+
+ /* bottom 6 bits of third word */
+ index = src[i+2] & 0x3F;
+ dest[j++] = raw_to_base64_table[index];
+ } else {
+ return BASE64_BUFFER_OVERRUN;
+ }
+ }
+
+ /* Check to see if any more work must be done */
+ if (i<src_bytes) {
+
+ /* Check to see if a newline should be output */
+ if (line_count>=MAX_BASE64_LINE_LENGTH) {
+ if (j<dmax){
+ dest[j++] = '\n';
+ } else {
+ return BASE64_BUFFER_OVERRUN;
+ }
+ line_count = 0;
+ }
+
+ line_count += 4;
+
+ /* Must fill another quantum */
+ if (j+4>dmax) {
+ /* No room left in output buffer! */
+ return BASE64_BUFFER_OVERRUN;
+ }
+
+ /* Find mapping of upper 6 bits */
+ index = (src[i] >> 2) & 0x3F;
+ dest[j++] = raw_to_base64_table[index];
+
+ /* check for another stragler */
+ if ((i+1)<src_bytes) {
+ /* bottom 2 bits of first word, high 4 bits of second word */
+ index = ((src[i] << 4) & 0x30) | ((src[i+1] >> 4) & 0x0F);
+ dest[j++] = raw_to_base64_table[index];
+
+ /* bottom 4 bits of second word */
+ index = (src[i+1] << 2) & 0x3C;
+ dest[j++] = raw_to_base64_table[index];
+ dest[j++] = PAD_CHAR;
+ } else {
+ /* bottom 2 bits of first word */
+ index = (src[i] << 4) & 0x30;
+ dest[j++] = raw_to_base64_table[index];
+ dest[j++] = PAD_CHAR;
+ dest[j++] = PAD_CHAR;
+ }
+ }
+
+ *dest_bytes = j;
+
+ return BASE64_SUCCESS;
+}
+
+unsigned char base64_decode_get_raw(unsigned char index)
+{
+ /* only have 128 values, MSB must not be set! */
+ if (index >= 128) {
+ return INVALID_CHAR;
+ }
+ return base64_to_raw_table[index];
+}
+
+/*
+ * base64_decode
+ *
+ * DESCRIPTION
+ * Decode data pointed to by src into the buffer pointer to by dest
+ * using the Base64 algorithm.
+ *
+ * PARAMETERS
+ * src = Pointer to the Base64 data to decode.
+ * src_bytes = The number of bytes in the src buffer to decode.
+ * dest = Pointer to the destination buffer where the converted data
+ * will reside when complete.
+ * dest_bytes = Initially holds the size of the destination buffer
+ * but at completion holds the number of bytes converted.
+ *
+ * RETURN VALUE
+ * base64_success if the buffer was successfully converted, the
+ * appropriate error code otherwise.
+ *
+ * The dest parameter holds the converted data.
+ *
+ * The dest_bytes parameter holds the actual number of bytes converted.
+ */
+base64_result_t base64_decode(unsigned char *src, int src_bytes, unsigned char *dest, int *dest_bytes)
+{
+ int i, j = 0;
+ int sindex = 0; /* Current NON-whitespace source
+ * index */
+ int pad_count=0; /* Number of padding characters
+ * encountered */
+ int dest_size_bytes = *dest_bytes; /* Save size of destination buffer */
+ unsigned char cindex; /* The current Base64 character to
+ * process */
+ unsigned char val; /* The value of the current Base64
+ * character */
+
+ *dest_bytes = 0;
+
+ for (i=0; i<src_bytes; i++) {
+ cindex = src[i];
+
+ val = base64_decode_get_raw(cindex);
+ if (val == INVALID_CHAR) {
+ /* Invalid base64 character */
+ return BASE64_BAD_DATA;
+ }
+
+ if (val == WHITE_SPACE) {
+ /* Ignore white space */
+ continue;
+ }
+
+ if (val == PADDING) {
+ /* we must be at the end-finish up */
+ pad_count++;
+ if (++i<src_bytes) {
+ /* can have up to 2 pad chars */
+ if (base64_decode_get_raw(src[i]) != PADDING) {
+ return BASE64_BAD_PADDING;
+ }
+
+ if (++i<src_bytes) {
+ /* should not have any more padding! */
+ return BASE64_BAD_PADDING;
+ }
+
+ pad_count++;
+ }
+
+ /* DONE! */
+ break;
+ }
+
+ /* Determine which portion of the 3 bytes this data will fill */
+ switch (sindex & 0x3) {
+ case 0:
+ /* Fill upper 6 bits */
+ if (j<dest_size_bytes) {
+ dest[j] = val << 2;
+ } else {
+ return BASE64_BUFFER_OVERRUN;
+ }
+ break;
+ case 1:
+ /* Fill Bottom 2 bits */
+ dest[j++] |= val >> 4;
+
+ if (j<dest_size_bytes) {
+ /* Fill Top 4 bits */
+ dest[j] = (val << 4) & 0xF0;
+ } else {
+ /*
+ * Check to see if there is any more data present.
+ * Next base64 character MUST be a pad character and
+ * the rest of this data MUST be zero.
+ *
+ * If this is not the end of data then a buffer overrun
+ * has occurred
+ */
+ if ((val & 0x0F) ||
+ (i+1>=src_bytes) ||
+ (base64_decode_get_raw(src[i+1]) != PADDING)) {
+ return BASE64_BUFFER_OVERRUN;
+ }
+ }
+ break;
+ case 2:
+ /* Fill Bottom 4 bits */
+ dest[j++] |= val >> 2;
+
+ if (j<dest_size_bytes) {
+ /* Fill Top 2 bits */
+ dest[j] = (val << 6) & 0xC0;
+ } else {
+ /*
+ * Check to see if there is any more data present.
+ * Next base64 character MUST be a pad character and
+ * the rest of this data MUST be zero.
+ *
+ * If this is not the end of data then a buffer overrun
+ * has occurred
+ */
+ if ((val & 0x03) ||
+ (i+1>=src_bytes) ||
+ (base64_decode_get_raw(src[i+1]) != PADDING)) {
+ return BASE64_BUFFER_OVERRUN;
+ }
+ }
+ break;
+ case 3:
+ /*
+ * No need to check for overrun here since the
+ * previous case was already checked. If another
+ * group is present then case 0 will check again.
+ */
+
+ /* Fill Bottom 6 bits */
+ dest[j++] |= val;
+ break;
+ }
+ sindex++;
+ }
+
+ /* Check length for multiple of 3 bytes */
+ if (((j + pad_count)% 3) != 0) {
+ return BASE64_BAD_BLOCK_SIZE;
+ }
+
+ /* Save off the number of bytes converted */
+ *dest_bytes = j;
+
+ return BASE64_SUCCESS;
+}
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