/* $OpenBSD: bio_b64.c,v 1.20 2015/02/07 13:19:15 doug Exp $ */ /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * "This product includes cryptographic software written by * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ #include #include #include #include #include static int b64_write(BIO *h, const char *buf, int num); static int b64_read(BIO *h, char *buf, int size); static int b64_puts(BIO *h, const char *str); /*static int b64_gets(BIO *h, char *str, int size); */ static long b64_ctrl(BIO *h, int cmd, long arg1, void *arg2); static int b64_new(BIO *h); static int b64_free(BIO *data); static long b64_callback_ctrl(BIO *h, int cmd, bio_info_cb *fp); #define B64_BLOCK_SIZE 1024 #define B64_BLOCK_SIZE2 768 #define B64_NONE 0 #define B64_ENCODE 1 #define B64_DECODE 2 typedef struct b64_struct { /*BIO *bio; moved to the BIO structure */ int buf_len; int buf_off; int tmp_len; /* used to find the start when decoding */ int tmp_nl; /* If true, scan until '\n' */ int encode; int start; /* have we started decoding yet? */ int cont; /* <= 0 when finished */ EVP_ENCODE_CTX base64; char buf[EVP_ENCODE_LENGTH(B64_BLOCK_SIZE) + 10]; char tmp[B64_BLOCK_SIZE]; } BIO_B64_CTX; static BIO_METHOD methods_b64 = { .type = BIO_TYPE_BASE64, .name = "base64 encoding", .bwrite = b64_write, .bread = b64_read, .bputs = b64_puts, .ctrl = b64_ctrl, .create = b64_new, .destroy = b64_free, .callback_ctrl = b64_callback_ctrl }; BIO_METHOD * BIO_f_base64(void) { return (&methods_b64); } static int b64_new(BIO *bi) { BIO_B64_CTX *ctx; ctx = malloc(sizeof(BIO_B64_CTX)); if (ctx == NULL) return (0); ctx->buf_len = 0; ctx->tmp_len = 0; ctx->tmp_nl = 0; ctx->buf_off = 0; ctx->cont = 1; ctx->start = 1; ctx->encode = 0; bi->init = 1; bi->ptr = (char *)ctx; bi->flags = 0; bi->num = 0; return (1); } static int b64_free(BIO *a) { if (a == NULL) return (0); free(a->ptr); a->ptr = NULL; a->init = 0; a->flags = 0; return (1); } static int b64_read(BIO *b, char *out, int outl) { int ret = 0, i, ii, j, k, x, n, num, ret_code = 0; BIO_B64_CTX *ctx; unsigned char *p, *q; if (out == NULL) return (0); ctx = (BIO_B64_CTX *)b->ptr; if ((ctx == NULL) || (b->next_bio == NULL)) return (0); BIO_clear_retry_flags(b); if (ctx->encode != B64_DECODE) { ctx->encode = B64_DECODE; ctx->buf_len = 0; ctx->buf_off = 0; ctx->tmp_len = 0; EVP_DecodeInit(&(ctx->base64)); } /* First check if there are bytes decoded/encoded */ if (ctx->buf_len > 0) { OPENSSL_assert(ctx->buf_len >= ctx->buf_off); i = ctx->buf_len - ctx->buf_off; if (i > outl) i = outl; OPENSSL_assert(ctx->buf_off + i < (int)sizeof(ctx->buf)); memcpy(out, &(ctx->buf[ctx->buf_off]), i); ret = i; out += i; outl -= i; ctx->buf_off += i; if (ctx->buf_len == ctx->buf_off) { ctx->buf_len = 0; ctx->buf_off = 0; } } /* At this point, we have room of outl bytes and an empty * buffer, so we should read in some more. */ ret_code = 0; while (outl > 0) { if (ctx->cont <= 0) break; i = BIO_read(b->next_bio, &(ctx->tmp[ctx->tmp_len]), B64_BLOCK_SIZE - ctx->tmp_len); if (i <= 0) { ret_code = i; /* Should we continue next time we are called? */ if (!BIO_should_retry(b->next_bio)) { ctx->cont = i; /* If buffer empty break */ if (ctx->tmp_len == 0) break; /* Fall through and process what we have */ else i = 0; } /* else we retry and add more data to buffer */ else break; } i += ctx->tmp_len; ctx->tmp_len = i; /* We need to scan, a line at a time until we * have a valid line if we are starting. */ if (ctx->start && (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL)) { /* ctx->start=1; */ ctx->tmp_len = 0; } else if (ctx->start) { q = p =(unsigned char *)ctx->tmp; num = 0; for (j = 0; j < i; j++) { if (*(q++) != '\n') continue; /* due to a previous very long line, * we need to keep on scanning for a '\n' * before we even start looking for * base64 encoded stuff. */ if (ctx->tmp_nl) { p = q; ctx->tmp_nl = 0; continue; } k = EVP_DecodeUpdate(&(ctx->base64), (unsigned char *)ctx->buf, &num, p, q - p); if ((k <= 0) && (num == 0) && (ctx->start)) EVP_DecodeInit(&ctx->base64); else { if (p != (unsigned char *) &(ctx->tmp[0])) { i -= (p - (unsigned char *) &(ctx->tmp[0])); for (x = 0; x < i; x++) ctx->tmp[x] = p[x]; } EVP_DecodeInit(&ctx->base64); ctx->start = 0; break; } p = q; } /* we fell off the end without starting */ if ((j == i) && (num == 0)) { /* Is this is one long chunk?, if so, keep on * reading until a new line. */ if (p == (unsigned char *)&(ctx->tmp[0])) { /* Check buffer full */ if (i == B64_BLOCK_SIZE) { ctx->tmp_nl = 1; ctx->tmp_len = 0; } } else if (p != q) /* finished on a '\n' */ { n = q - p; for (ii = 0; ii < n; ii++) ctx->tmp[ii] = p[ii]; ctx->tmp_len = n; } /* else finished on a '\n' */ continue; } else { ctx->tmp_len = 0; } } else if ((i < B64_BLOCK_SIZE) && (ctx->cont > 0)) { /* If buffer isn't full and we can retry then * restart to read in more data. */ continue; } if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL) { int z, jj; jj = i & ~3; /* process per 4 */ z = EVP_DecodeBlock((unsigned char *)ctx->buf, (unsigned char *)ctx->tmp, jj); if (jj > 2) { if (ctx->tmp[jj-1] == '=') { z--; if (ctx->tmp[jj-2] == '=') z--; } } /* z is now number of output bytes and jj is the * number consumed */ if (jj != i) { memmove(ctx->tmp, &ctx->tmp[jj], i - jj); ctx->tmp_len = i - jj; } ctx->buf_len = 0; if (z > 0) { ctx->buf_len = z; } i = z; } else { i = EVP_DecodeUpdate(&(ctx->base64), (unsigned char *)ctx->buf, &ctx->buf_len, (unsigned char *)ctx->tmp, i); ctx->tmp_len = 0; } ctx->buf_off = 0; if (i < 0) { ret_code = 0; ctx->buf_len = 0; break; } if (ctx->buf_len <= outl) i = ctx->buf_len; else i = outl; memcpy(out, ctx->buf, i); ret += i; ctx->buf_off = i; if (ctx->buf_off == ctx->buf_len) { ctx->buf_len = 0; ctx->buf_off = 0; } outl -= i; out += i; } /* BIO_clear_retry_flags(b); */ BIO_copy_next_retry(b); return ((ret == 0) ? ret_code : ret); } static int b64_write(BIO *b, const char *in, int inl) { int ret = 0; int n; int i; BIO_B64_CTX *ctx; ctx = (BIO_B64_CTX *)b->ptr; BIO_clear_retry_flags(b); if (ctx->encode != B64_ENCODE) { ctx->encode = B64_ENCODE; ctx->buf_len = 0; ctx->buf_off = 0; ctx->tmp_len = 0; EVP_EncodeInit(&(ctx->base64)); } OPENSSL_assert(ctx->buf_off < (int)sizeof(ctx->buf)); OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf)); OPENSSL_assert(ctx->buf_len >= ctx->buf_off); n = ctx->buf_len - ctx->buf_off; while (n > 0) { i = BIO_write(b->next_bio, &(ctx->buf[ctx->buf_off]), n); if (i <= 0) { BIO_copy_next_retry(b); return (i); } OPENSSL_assert(i <= n); ctx->buf_off += i; OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf)); OPENSSL_assert(ctx->buf_len >= ctx->buf_off); n -= i; } /* at this point all pending data has been written */ ctx->buf_off = 0; ctx->buf_len = 0; if ((in == NULL) || (inl <= 0)) return (0); while (inl > 0) { n = (inl > B64_BLOCK_SIZE) ? B64_BLOCK_SIZE : inl; if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL) { if (ctx->tmp_len > 0) { OPENSSL_assert(ctx->tmp_len <= 3); n = 3 - ctx->tmp_len; /* There's a theoretical possibility for this */ if (n > inl) n = inl; memcpy(&(ctx->tmp[ctx->tmp_len]), in, n); ctx->tmp_len += n; ret += n; if (ctx->tmp_len < 3) break; ctx->buf_len = EVP_EncodeBlock( (unsigned char *)ctx->buf, (unsigned char *)ctx->tmp, ctx->tmp_len); OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf)); OPENSSL_assert(ctx->buf_len >= ctx->buf_off); /* Since we're now done using the temporary buffer, the length should be 0'd */ ctx->tmp_len = 0; } else { if (n < 3) { memcpy(ctx->tmp, in, n); ctx->tmp_len = n; ret += n; break; } n -= n % 3; ctx->buf_len = EVP_EncodeBlock( (unsigned char *)ctx->buf, (const unsigned char *)in, n); OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf)); OPENSSL_assert(ctx->buf_len >= ctx->buf_off); ret += n; } } else { EVP_EncodeUpdate(&(ctx->base64), (unsigned char *)ctx->buf, &ctx->buf_len, (unsigned char *)in, n); OPENSSL_assert(ctx->buf_len <= (int)sizeof(ctx->buf)); OPENSSL_assert(ctx->buf_len >= ctx->buf_off); ret += n; } inl -= n; in += n; ctx->buf_off = 0; n = ctx->buf_len; while (n > 0) { i = BIO_write(b->next_bio, &(ctx->buf[ctx->buf_off]), n); if (i <= 0) { BIO_copy_next_retry(b); return ((ret == 0) ? i : ret); } OPENSSL_assert(i <= n); n -= i; ctx->buf_off += i; OPENSSL_assert(ctx->buf_off <= (int)sizeof(ctx->buf)); OPENSSL_assert(ctx->buf_len >= ctx->buf_off); } ctx->buf_len = 0; ctx->buf_off = 0; } return (ret); } static long b64_ctrl(BIO *b, int cmd, long num, void *ptr) { BIO_B64_CTX *ctx; long ret = 1; int i; ctx = (BIO_B64_CTX *)b->ptr; switch (cmd) { case BIO_CTRL_RESET: ctx->cont = 1; ctx->start = 1; ctx->encode = B64_NONE; ret = BIO_ctrl(b->next_bio, cmd, num, ptr); break; case BIO_CTRL_EOF: /* More to read */ if (ctx->cont <= 0) ret = 1; else ret = BIO_ctrl(b->next_bio, cmd, num, ptr); break; case BIO_CTRL_WPENDING: /* More to write in buffer */ OPENSSL_assert(ctx->buf_len >= ctx->buf_off); ret = ctx->buf_len - ctx->buf_off; if ((ret == 0) && (ctx->encode != B64_NONE) && (ctx->base64.num != 0)) ret = 1; else if (ret <= 0) ret = BIO_ctrl(b->next_bio, cmd, num, ptr); break; case BIO_CTRL_PENDING: /* More to read in buffer */ OPENSSL_assert(ctx->buf_len >= ctx->buf_off); ret = ctx->buf_len - ctx->buf_off; if (ret <= 0) ret = BIO_ctrl(b->next_bio, cmd, num, ptr); break; case BIO_CTRL_FLUSH: /* do a final write */ again: while (ctx->buf_len != ctx->buf_off) { i = b64_write(b, NULL, 0); if (i < 0) return i; } if (BIO_get_flags(b) & BIO_FLAGS_BASE64_NO_NL) { if (ctx->tmp_len != 0) { ctx->buf_len = EVP_EncodeBlock( (unsigned char *)ctx->buf, (unsigned char *)ctx->tmp, ctx->tmp_len); ctx->buf_off = 0; ctx->tmp_len = 0; goto again; } } else if (ctx->encode != B64_NONE && ctx->base64.num != 0) { ctx->buf_off = 0; EVP_EncodeFinal(&(ctx->base64), (unsigned char *)ctx->buf, &(ctx->buf_len)); /* push out the bytes */ goto again; } /* Finally flush the underlying BIO */ ret = BIO_ctrl(b->next_bio, cmd, num, ptr); break; case BIO_C_DO_STATE_MACHINE: BIO_clear_retry_flags(b); ret = BIO_ctrl(b->next_bio, cmd, num, ptr); BIO_copy_next_retry(b); break; case BIO_CTRL_DUP: break; case BIO_CTRL_INFO: case BIO_CTRL_GET: case BIO_CTRL_SET: default: ret = BIO_ctrl(b->next_bio, cmd, num, ptr); break; } return (ret); } static long b64_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp) { long ret = 1; if (b->next_bio == NULL) return (0); switch (cmd) { default: ret = BIO_callback_ctrl(b->next_bio, cmd, fp); break; } return (ret); } static int b64_puts(BIO *b, const char *str) { return b64_write(b, str, strlen(str)); }