diff options
Diffstat (limited to 'g10/decrypt-data.c')
| -rw-r--r-- | g10/decrypt-data.c | 135 |
1 files changed, 58 insertions, 77 deletions
diff --git a/g10/decrypt-data.c b/g10/decrypt-data.c index b5cc7d3c6..426b12421 100644 --- a/g10/decrypt-data.c +++ b/g10/decrypt-data.c @@ -331,6 +331,59 @@ decrypt_data (ctrl_t ctrl, void *procctx, PKT_encrypted *ed, DEK *dek) } +/* Fill BUFFER with up to NBYTES-OFFSET from STREAM utilizing + * information from the context DFX. Returns the new offset which is + * the number of bytes read plus the original offset. On EOF the + * respective flag in DFX is set. */ +static size_t +fill_buffer (decode_filter_ctx_t dfx, iobuf_t stream, + byte *buffer, size_t nbytes, size_t offset) +{ + size_t nread = offset; + size_t curr; + int ret; + + if (dfx->partial) + { + while (nread < nbytes) + { + curr = nbytes - nread; + + ret = iobuf_read (stream, &buffer[nread], curr); + if (ret == -1) + { + dfx->eof_seen = 1; /* Normal EOF. */ + break; + } + + nread += ret; + } + } + else + { + while (nread < nbytes && dfx->length) + { + curr = nbytes - nread; + if (curr > dfx->length) + curr = dfx->length; + + ret = iobuf_read (stream, &buffer[nread], curr); + if (ret == -1) + { + dfx->eof_seen = 3; /* Premature EOF. */ + break; + } + + nread += ret; + dfx->length -= ret; + } + if (!dfx->length) + dfx->eof_seen = 1; /* Normal EOF. */ + } + + return nread; +} + static int mdc_decode_filter (void *opaque, int control, IOBUF a, @@ -339,7 +392,6 @@ mdc_decode_filter (void *opaque, int control, IOBUF a, decode_filter_ctx_t dfx = opaque; size_t n, size = *ret_len; int rc = 0; - int c; /* Note: We need to distinguish between a partial and a fixed length packet. The first is the usual case as created by GPG. However @@ -360,25 +412,7 @@ mdc_decode_filter (void *opaque, int control, IOBUF a, log_assert (size > 44); /* Our code requires at least this size. */ /* Get at least 22 bytes and put it ahead in the buffer. */ - if (dfx->partial) - { - for (n=22; n < 44; n++) - { - if ( (c = iobuf_get(a)) == -1 ) - break; - buf[n] = c; - } - } - else - { - for (n=22; n < 44 && dfx->length; n++, dfx->length--) - { - c = iobuf_get (a); - if (c == -1) - break; /* Premature EOF. */ - buf[n] = c; - } - } + n = fill_buffer (dfx, a, buf, 44, 22); if (n == 44) { /* We have enough stuff - flush the deferred stuff. */ @@ -392,35 +426,9 @@ mdc_decode_filter (void *opaque, int control, IOBUF a, memcpy (buf, dfx->holdback, 22); } /* Fill up the buffer. */ - if (dfx->partial) - { - for (; n < size; n++ ) - { - if ( (c = iobuf_get(a)) == -1 ) - { - dfx->eof_seen = 1; /* Normal EOF. */ - break; - } - buf[n] = c; - } - } - else - { - for (; n < size && dfx->length; n++, dfx->length--) - { - c = iobuf_get(a); - if (c == -1) - { - dfx->eof_seen = 3; /* Premature EOF. */ - break; - } - buf[n] = c; - } - if (!dfx->length) - dfx->eof_seen = 1; /* Normal EOF. */ - } + n = fill_buffer (dfx, a, buf, size, n); - /* Move the trailing 22 bytes back to the defer buffer. We + /* Move the trailing 22 bytes back to the holdback buffer. We have at least 44 bytes thus a memmove is not needed. */ n -= 22; memcpy (dfx->holdback, buf+n, 22 ); @@ -473,7 +481,7 @@ decode_filter( void *opaque, int control, IOBUF a, byte *buf, size_t *ret_len) decode_filter_ctx_t fc = opaque; size_t size = *ret_len; size_t n; - int c, rc = 0; + int rc = 0; if ( control == IOBUFCTRL_UNDERFLOW && fc->eof_seen ) @@ -485,34 +493,7 @@ decode_filter( void *opaque, int control, IOBUF a, byte *buf, size_t *ret_len) { log_assert (a); - if (fc->partial) - { - for (n=0; n < size; n++ ) - { - c = iobuf_get(a); - if (c == -1) - { - fc->eof_seen = 1; /* Normal EOF. */ - break; - } - buf[n] = c; - } - } - else - { - for (n=0; n < size && fc->length; n++, fc->length--) - { - c = iobuf_get(a); - if (c == -1) - { - fc->eof_seen = 3; /* Premature EOF. */ - break; - } - buf[n] = c; - } - if (!fc->length) - fc->eof_seen = 1; /* Normal EOF. */ - } + n = fill_buffer (fc, a, buf, size, 0); if (n) { if (fc->cipher_hd) |