Restore error code from DecodeGeneralName

[embhorn]

Description

PR #10279 added DecodeGeneralNameCheckChars, which returns ASN_PARSE_E for an embedded NUL in dNSName/rfc822Name/URI SANs, aborting the whole certificate parse before hostname matching ever runs. This broke cert testing in curl and changed the expected failure mode.

Fixes #10790

Dependency on fix in Python OSP wolfSSL/osp#347

Testing

• tests/api/test_asn.c — updated the NUL sub-case: the cert now must parse (was ASN_PARSE_E), with the entry stored and the embedded NUL preserved (length 4, not truncated).
• tests/api/test_ossl_x509.c — new test_wolfSSL_X509_check_host_embedded_nul_san: the exact curl-311 scenario (CN=localhost, SAN=localhost\0h). Pins that the cert parses and the host is still rejected (correct CN must not rescue the wrong SAN).

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[Copilot]

Pull request overview

Adjusts X.509 SubjectAltName parsing so embedded NUL bytes in IA5String-based GeneralNames (dNSName/rfc822Name/URI) do not abort certificate parsing with ASN_PARSE_E, restoring the expected verification-time failure mode (e.g., DOMAIN_NAME_MISMATCH) and fixing the curl test 311 regression described in #10790.

Changes:

• Stop rejecting embedded-NUL IA5String SAN values at parse time by removing DecodeGeneralNameCheckChars from both ASN parsers.
• Add/adjust tests to ensure certificates with embedded-NUL dNSName SANs still parse and store the full (non-truncated) value, while hostname verification still fails.
• Update doxygen to warn that wolfSSL_X509_get_next_altname() returns a C string without a length and can be silently truncated by embedded NULs.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
wolfcrypt/src/asn.c	Removes parse-time NUL rejection for GeneralName IA5String SANs; documents rationale in-code.
wolfcrypt/src/asn_orig.c	Mirrors the same behavior change in the legacy ASN parser.
tests/api/test_asn.c	Updates SAN tests to require parse success and verify embedded NUL is preserved in stored altName data.
tests/api/test_ossl_x509.h	Registers the new regression test in the ossl_x509 test group.
tests/api/test_ossl_x509.c	Adds regression test reproducing curl-311 scenario (good CN, bad SAN with embedded NUL).
doc/dox_comments/header_files/ssl.h	Adds API documentation warning about embedded NUL truncation with wolfSSL_X509_get_next_altname().

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[wolfSSL-Fenrir-bot]

Fenrir Automated Review — PR #10793

Scan targets checked: wolfcrypt-bugs, wolfcrypt-rs-bugs, wolfcrypt-src, wolfssl-bugs, wolfssl-src

No new issues found in the changed files. ✅

[github-actions]

retest this please

[github-actions]

MemBrowse Memory Report

gcc-arm-cortex-m0plus

• FLASH: .text -56 B (-0.1%, 63,439 B / 262,144 B, total: 24% used)

gcc-arm-cortex-m3

• FLASH: .text -56 B (-0.0%, 121,353 B / 262,144 B, total: 46% used)

gcc-arm-cortex-m4

• FLASH: .text -64 B (-0.0%, 198,988 B / 262,144 B, total: 76% used)

gcc-arm-cortex-m4-baremetal

• FLASH: .text -64 B (-0.1%, 65,995 B / 262,144 B, total: 25% used)

gcc-arm-cortex-m4-crypto-only

• FLASH: .text -64 B (-0.0%, 173,610 B / 262,144 B, total: 66% used)

gcc-arm-cortex-m4-dtls13

• FLASH: .text -64 B (-0.0%, 179,736 B / 1,048,576 B, total: 17% used)

gcc-arm-cortex-m4-min-ecc

• FLASH: .text -64 B (-0.1%, 60,973 B / 262,144 B, total: 23% used)

gcc-arm-cortex-m4-openssl-compat

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gcc-arm-cortex-m4-pkcs7

• FLASH: .text -64 B (-0.0%, 211,309 B / 262,144 B, total: 81% used)

gcc-arm-cortex-m4-rsa-only

• FLASH: .text -64 B (-0.0%, 323,408 B / 1,048,576 B, total: 31% used)

gcc-arm-cortex-m4-sp-math

• FLASH: .text -64 B (-0.1%, 60,973 B / 262,144 B, total: 23% used)

gcc-arm-cortex-m4-tls12

• FLASH: .text -64 B (-0.1%, 122,125 B / 262,144 B, total: 47% used)

gcc-arm-cortex-m4-tls13

• FLASH: .text -64 B (-0.0%, 234,686 B / 262,144 B, total: 90% used)

gcc-arm-cortex-m7

• FLASH: .text -64 B (-0.0%, 198,988 B / 262,144 B, total: 76% used)

gcc-arm-cortex-m7-tls13

• FLASH: .text -64 B (-0.0%, 234,686 B / 262,144 B, total: 90% used)

linuxkm-pie

• Data: __patchable_function_entries -8 B (-0.0%, 24,280 B)

stm32-sim-stm32h753

• FLASH: .text -128 B (-0.1%, 181,556 B / 2,097,152 B, total: 9% used)
  No memory changes detected for:
• gcc-arm-cortex-m4-pq
• gcc-arm-cortex-m7-pq
• linuxkm-standard