diff options
Diffstat (limited to 'crypto/pem/pem_lib.c')
| -rw-r--r-- | crypto/pem/pem_lib.c | 411 |
1 files changed, 270 insertions, 141 deletions
diff --git a/crypto/pem/pem_lib.c b/crypto/pem/pem_lib.c index 3f53fd892d..24320131a4 100644 --- a/crypto/pem/pem_lib.c +++ b/crypto/pem/pem_lib.c @@ -228,6 +228,20 @@ static int check_pem(const char *nm, const char *name) return 0; } +static void pem_free(void *p, unsigned int flags) +{ + if (flags & PEM_FLAG_SECURE) + OPENSSL_secure_free(p); + else + OPENSSL_free(p); +} + +static void *pem_malloc(int num, unsigned int flags) +{ + return (flags & PEM_FLAG_SECURE) ? OPENSSL_secure_malloc(num) + : OPENSSL_malloc(num); +} + int PEM_bytes_read_bio(unsigned char **pdata, long *plen, char **pnm, const char *name, BIO *bp, pem_password_cb *cb, void *u) @@ -661,177 +675,292 @@ int PEM_read(FILE *fp, char **name, char **header, unsigned char **data, } #endif -int PEM_read_bio(BIO *bp, char **name, char **header, unsigned char **data, - long *len) +/* Some helpers for PEM_read_bio_ex(). */ + +#define isb64(c) (isalnum(c) || (c) == '+' || (c) == '/' || (c) == '=') + +static int sanitize_line(char *linebuf, int len, unsigned int flags) { - EVP_ENCODE_CTX *ctx = EVP_ENCODE_CTX_new(); - int end = 0, i, k, bl = 0, hl = 0, nohead = 0; - char buf[256]; - BUF_MEM *nameB; - BUF_MEM *headerB; - BUF_MEM *dataB, *tmpB; + int i; - if (ctx == NULL) { - PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE); - return (0); + if (flags & PEM_FLAG_EAY_COMPATIBLE) { + /* Strip trailing whitespace */ + while ((len >= 0) && (linebuf[len] <= ' ')) + len--; + /* Go back to whitespace before applying uniform line ending. */ + len++; + } else if (flags & PEM_FLAG_ONLY_B64) { + for (i = 0; i < len; ++i) { + if (!isb64(linebuf[i]) || linebuf[i] == '\n' || linebuf[i] == '\r') + break; + } + len = i; + } else { + /* EVP_DecodeBlock strips leading and trailing whitespace, so just strip + * control characters in-place and let everything through. */ + for (i = 0; i < len; ++i) { + if (linebuf[i] == '\n' || linebuf[i] == '\r') + break; + if (iscntrl(linebuf[i])) + linebuf[i] = ' '; + } + len = i; } + /* The caller allocated LINESIZE+1, so this is safe. */ + linebuf[len++] = '\n'; + linebuf[len] = '\0'; + return len; +} - nameB = BUF_MEM_new(); - headerB = BUF_MEM_new(); - dataB = BUF_MEM_new(); - if ((nameB == NULL) || (headerB == NULL) || (dataB == NULL)) { - goto err; +#define LINESIZE 255 +/* Note trailing spaces for begin and end. */ +static const char beginstr[] = "-----BEGIN "; +static const char endstr[] = "-----END "; +static const char tailstr[] = "-----\n"; +#define BEGINLEN (sizeof(beginstr) - 1) +#define ENDLEN (sizeof(endstr) - 1) +#define TAILLEN (sizeof(tailstr) - 1) +static int get_name(BIO *bp, char **name, unsigned int flags) +{ + char *linebuf; + int ret = 0; + size_t len; + + /* + * Need to hold trailing NUL (accounted for by BIO_gets() and the newline + * that will be added by sanitize_line() (the extra '1'). + */ + linebuf = pem_malloc(LINESIZE + 1, flags); + if (linebuf == NULL) { + PEMerr(PEM_F_GET_NAME, ERR_R_MALLOC_FAILURE); + return 0; } - buf[254] = '\0'; - for (;;) { - i = BIO_gets(bp, buf, 254); + do { + len = BIO_gets(bp, linebuf, LINESIZE); - if (i <= 0) { - PEMerr(PEM_F_PEM_READ_BIO, PEM_R_NO_START_LINE); + if (len <= 0) { + PEMerr(PEM_F_GET_NAME, PEM_R_NO_START_LINE); goto err; } - while ((i >= 0) && (buf[i] <= ' ')) - i--; - buf[++i] = '\n'; - buf[++i] = '\0'; + /* Strip trailing garbage and standardize ending. */ + len = sanitize_line(linebuf, len, flags & ~PEM_FLAG_ONLY_B64); + + /* Allow leading empty or non-matching lines. */ + } while (strncmp(linebuf, beginstr, BEGINLEN) != 0 + || len < TAILLEN + || strncmp(linebuf + len - TAILLEN, tailstr, TAILLEN) != 0); + linebuf[len - TAILLEN] = '\0'; + len = len - BEGINLEN - TAILLEN + 1; + *name = pem_malloc(len, flags); + if (*name == NULL) { + PEMerr(PEM_F_GET_NAME, ERR_R_MALLOC_FAILURE); + goto err; + } + memcpy(*name, linebuf + BEGINLEN, len); + ret = 1; + +err: + pem_free(linebuf, flags); + return ret; +} + +/* Keep track of how much of a header we've seen. */ +enum header_status { + MAYBE_HEADER, + IN_HEADER, + POST_HEADER +}; + +/** + * Extract the optional PEM header, with details on the type of content and + * any encryption used on the contents, and the bulk of the data from the bio. + * The end of the header is marked by a blank line; if the end-of-input marker + * is reached prior to a blank line, there is no header. + * + * The header and data arguments are BIO** since we may have to swap them + * if there is no header, for efficiency. + * + * We need the name of the PEM-encoded type to verify the end string. + */ +static int get_header_and_data(BIO *bp, BIO **header, BIO **data, char *name, + unsigned int flags) +{ + BIO *tmp = *header; + char *linebuf, *p; + int len, line, ret = 0, end = 0; + /* 0 if not seen (yet), 1 if reading header, 2 if finished header */ + enum header_status got_header = MAYBE_HEADER; + unsigned int flags_mask; + size_t namelen; + + /* Need to hold trailing NUL (accounted for by BIO_gets() and the newline + * that will be added by sanitize_line() (the extra '1'). */ + linebuf = pem_malloc(LINESIZE + 1, flags); + if (linebuf == NULL) { + PEMerr(PEM_F_GET_HEADER_AND_DATA, ERR_R_MALLOC_FAILURE); + return 0; + } - if (strncmp(buf, "-----BEGIN ", 11) == 0) { - i = strlen(&(buf[11])); + for (line = 0; ; line++) { + flags_mask = ~0u; + len = BIO_gets(bp, linebuf, LINESIZE); + if (len <= 0) { + PEMerr(PEM_F_GET_HEADER_AND_DATA, PEM_R_SHORT_HEADER); + goto err; + } - if (strncmp(&(buf[11 + i - 6]), "-----\n", 6) != 0) - continue; - if (!BUF_MEM_grow(nameB, i + 9)) { - PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE); + if (got_header == MAYBE_HEADER) { + if (memchr(linebuf, ':', len) != NULL) + got_header = IN_HEADER; + } + if (!strncmp(linebuf, endstr, ENDLEN) || got_header == IN_HEADER) + flags_mask &= ~PEM_FLAG_ONLY_B64; + len = sanitize_line(linebuf, len, flags & flags_mask); + + /* Check for end of header. */ + if (linebuf[0] == '\n') { + if (got_header == POST_HEADER) { + /* Another blank line is an error. */ + PEMerr(PEM_F_GET_HEADER_AND_DATA, PEM_R_BAD_END_LINE); goto err; } - memcpy(nameB->data, &(buf[11]), i - 6); - nameB->data[i - 6] = '\0'; - break; + got_header = POST_HEADER; + tmp = *data; + continue; } - } - hl = 0; - if (!BUF_MEM_grow(headerB, 256)) { - PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE); - goto err; - } - headerB->data[0] = '\0'; - for (;;) { - i = BIO_gets(bp, buf, 254); - if (i <= 0) - break; - - while ((i >= 0) && (buf[i] <= ' ')) - i--; - buf[++i] = '\n'; - buf[++i] = '\0'; - if (buf[0] == '\n') + /* Check for end of stream (which means there is no header). */ + if (strncmp(linebuf, endstr, ENDLEN) == 0) { + p = linebuf + ENDLEN; + namelen = strlen(name); + if (strncmp(p, name, namelen) != 0 || + strncmp(p + namelen, tailstr, TAILLEN) != 0) { + PEMerr(PEM_F_GET_HEADER_AND_DATA, PEM_R_BAD_END_LINE); + goto err; + } + if (got_header == MAYBE_HEADER) { + *header = *data; + *data = tmp; + } break; - if (!BUF_MEM_grow(headerB, hl + i + 9)) { - PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE); + } else if (end) { + /* Malformed input; short line not at end of data. */ + PEMerr(PEM_F_GET_HEADER_AND_DATA, PEM_R_BAD_END_LINE); goto err; } - if (strncmp(buf, "-----END ", 9) == 0) { - nohead = 1; - break; + /* + * Else, a line of text -- could be header or data; we don't + * know yet. Just pass it through. + */ + BIO_puts(tmp, linebuf); + /* + * Only encrypted files need the line length check applied. + */ + if (got_header == POST_HEADER) { + /* 65 includes the trailing newline */ + if (len > 65) + goto err; + if (len < 65) + end = 1; } - memcpy(&(headerB->data[hl]), buf, i); - headerB->data[hl + i] = '\0'; - hl += i; - } - - bl = 0; - if (!BUF_MEM_grow(dataB, 1024)) { - PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE); - goto err; } - dataB->data[0] = '\0'; - if (!nohead) { - for (;;) { - i = BIO_gets(bp, buf, 254); - if (i <= 0) - break; - while ((i >= 0) && (buf[i] <= ' ')) - i--; - buf[++i] = '\n'; - buf[++i] = '\0'; + ret = 1; +err: + pem_free(linebuf, flags); + return ret; +} - if (i != 65) - end = 1; - if (strncmp(buf, "-----END ", 9) == 0) - break; - if (i > 65) - break; - if (!BUF_MEM_grow_clean(dataB, i + bl + 9)) { - PEMerr(PEM_F_PEM_READ_BIO, ERR_R_MALLOC_FAILURE); - goto err; - } - memcpy(&(dataB->data[bl]), buf, i); - dataB->data[bl + i] = '\0'; - bl += i; - if (end) { - buf[0] = '\0'; - i = BIO_gets(bp, buf, 254); - if (i <= 0) - break; - - while ((i >= 0) && (buf[i] <= ' ')) - i--; - buf[++i] = '\n'; - buf[++i] = '\0'; +/** + * Read in PEM-formatted data from the given BIO. + * + * By nature of the PEM format, all content must be printable ASCII (except + * for line endings). Other characters, or lines that are longer than 80 + * characters, are malformed input and will be rejected. + */ +int PEM_read_bio_ex(BIO *bp, char **name_out, char **header, + unsigned char **data, long *len_out, unsigned int flags) +{ + EVP_ENCODE_CTX *ctx = EVP_ENCODE_CTX_new(); + const BIO_METHOD *bmeth; + BIO *headerB = NULL, *dataB = NULL; + char *name = NULL; + int len, taillen, headerlen, ret = 0; + BUF_MEM * buf_mem; - break; - } - } - } else { - tmpB = headerB; - headerB = dataB; - dataB = tmpB; - bl = hl; - } - i = strlen(nameB->data); - if ((strncmp(buf, "-----END ", 9) != 0) || - (strncmp(nameB->data, &(buf[9]), i) != 0) || - (strncmp(&(buf[9 + i]), "-----\n", 6) != 0)) { - PEMerr(PEM_F_PEM_READ_BIO, PEM_R_BAD_END_LINE); - goto err; + if (ctx == NULL) { + PEMerr(PEM_F_PEM_READ_BIO_EX, ERR_R_MALLOC_FAILURE); + return 0; } - EVP_DecodeInit(ctx); - i = EVP_DecodeUpdate(ctx, - (unsigned char *)dataB->data, &bl, - (unsigned char *)dataB->data, bl); - if (i < 0) { - PEMerr(PEM_F_PEM_READ_BIO, PEM_R_BAD_BASE64_DECODE); - goto err; + *len_out = 0; + *name_out = *header = NULL; + *data = NULL; + if ((flags & PEM_FLAG_EAY_COMPATIBLE) && (flags & PEM_FLAG_ONLY_B64)) { + /* These two are mutually incompatible; bail out. */ + PEMerr(PEM_F_PEM_READ_BIO_EX, ERR_R_PASSED_INVALID_ARGUMENT); + goto end; } - i = EVP_DecodeFinal(ctx, (unsigned char *)&(dataB->data[bl]), &k); - if (i < 0) { - PEMerr(PEM_F_PEM_READ_BIO, PEM_R_BAD_BASE64_DECODE); - goto err; + bmeth = (flags & PEM_FLAG_SECURE) ? BIO_s_secmem() : BIO_s_mem(); + + headerB = BIO_new(bmeth); + dataB = BIO_new(bmeth); + if (headerB == NULL || dataB == NULL) { + PEMerr(PEM_F_PEM_READ_BIO_EX, ERR_R_MALLOC_FAILURE); + goto end; } - bl += k; - if (bl == 0) - goto err; - *name = nameB->data; - *header = headerB->data; - *data = (unsigned char *)dataB->data; - *len = bl; - OPENSSL_free(nameB); - OPENSSL_free(headerB); - OPENSSL_free(dataB); - EVP_ENCODE_CTX_free(ctx); - return (1); - err: - BUF_MEM_free(nameB); - BUF_MEM_free(headerB); - BUF_MEM_free(dataB); + if (!get_name(bp, &name, flags)) + goto end; + if (!get_header_and_data(bp, &headerB, &dataB, name, flags)) + goto end; + + EVP_DecodeInit(ctx); + BIO_get_mem_ptr(dataB, &buf_mem); + len = buf_mem->length; + if (EVP_DecodeUpdate(ctx, (unsigned char*)buf_mem->data, &len, + (unsigned char*)buf_mem->data, len) < 0 + || EVP_DecodeFinal(ctx, (unsigned char*)&(buf_mem->data[len]), + &taillen) < 0) { + PEMerr(PEM_F_PEM_READ_BIO_EX, PEM_R_BAD_BASE64_DECODE); + goto end; + } + len += taillen; + buf_mem->length = len; + + /* There was no data in the PEM file; avoid malloc(0). */ + if (len == 0) + goto end; + headerlen = BIO_get_mem_data(headerB, NULL); + *header = pem_malloc(headerlen + 1, flags); + *data = pem_malloc(len, flags); + if (*header == NULL || *data == NULL) { + pem_free(*header, flags); + pem_free(*data, flags); + goto end; + } + BIO_read(headerB, *header, headerlen); + (*header)[headerlen] = '\0'; + BIO_read(dataB, *data, len); + *len_out = len; + *name_out = name; + name = NULL; + ret = 1; + +end: EVP_ENCODE_CTX_free(ctx); - return (0); + pem_free(name, flags); + BIO_free(headerB); + BIO_free(dataB); + return ret; +} + +int PEM_read_bio(BIO *bp, char **name, char **header, unsigned char **data, + long *len) +{ + return PEM_read_bio_ex(bp, name, header, data, len, PEM_FLAG_EAY_COMPATIBLE); } /* |